.. | .. |
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1 | | -// SPDX-License-Identifier: LGPL-2.1 |
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| 1 | +// SPDX-License-Identifier: (LGPL-2.1 OR BSD-2-Clause) |
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2 | 2 | |
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3 | 3 | /* |
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4 | 4 | * Common eBPF ELF object loading operations. |
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.. | .. |
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7 | 7 | * Copyright (C) 2015 Wang Nan <wangnan0@huawei.com> |
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8 | 8 | * Copyright (C) 2015 Huawei Inc. |
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9 | 9 | * Copyright (C) 2017 Nicira, Inc. |
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10 | | - * |
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11 | | - * This program is free software; you can redistribute it and/or |
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12 | | - * modify it under the terms of the GNU Lesser General Public |
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13 | | - * License as published by the Free Software Foundation; |
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14 | | - * version 2.1 of the License (not later!) |
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15 | | - * |
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16 | | - * This program is distributed in the hope that it will be useful, |
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17 | | - * but WITHOUT ANY WARRANTY; without even the implied warranty of |
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18 | | - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
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19 | | - * GNU Lesser General Public License for more details. |
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20 | | - * |
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21 | | - * You should have received a copy of the GNU Lesser General Public |
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22 | | - * License along with this program; if not, see <http://www.gnu.org/licenses> |
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| 10 | + * Copyright (C) 2019 Isovalent, Inc. |
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23 | 11 | */ |
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24 | 12 | |
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25 | 13 | #ifndef _GNU_SOURCE |
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.. | .. |
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30 | 18 | #include <stdarg.h> |
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31 | 19 | #include <libgen.h> |
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32 | 20 | #include <inttypes.h> |
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| 21 | +#include <limits.h> |
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33 | 22 | #include <string.h> |
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34 | 23 | #include <unistd.h> |
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| 24 | +#include <endian.h> |
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35 | 25 | #include <fcntl.h> |
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36 | 26 | #include <errno.h> |
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37 | | -#include <perf-sys.h> |
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| 27 | +#include <ctype.h> |
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38 | 28 | #include <asm/unistd.h> |
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39 | 29 | #include <linux/err.h> |
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40 | 30 | #include <linux/kernel.h> |
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41 | 31 | #include <linux/bpf.h> |
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42 | 32 | #include <linux/btf.h> |
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| 33 | +#include <linux/filter.h> |
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43 | 34 | #include <linux/list.h> |
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44 | 35 | #include <linux/limits.h> |
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| 36 | +#include <linux/perf_event.h> |
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| 37 | +#include <linux/ring_buffer.h> |
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| 38 | +#include <linux/version.h> |
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| 39 | +#include <sys/epoll.h> |
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| 40 | +#include <sys/ioctl.h> |
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| 41 | +#include <sys/mman.h> |
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45 | 42 | #include <sys/stat.h> |
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46 | 43 | #include <sys/types.h> |
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47 | 44 | #include <sys/vfs.h> |
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48 | | -#include <tools/libc_compat.h> |
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| 45 | +#include <sys/utsname.h> |
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| 46 | +#include <sys/resource.h> |
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49 | 47 | #include <libelf.h> |
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50 | 48 | #include <gelf.h> |
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| 49 | +#include <zlib.h> |
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51 | 50 | |
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52 | 51 | #include "libbpf.h" |
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53 | 52 | #include "bpf.h" |
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54 | 53 | #include "btf.h" |
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55 | 54 | #include "str_error.h" |
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| 55 | +#include "libbpf_internal.h" |
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| 56 | +#include "hashmap.h" |
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56 | 57 | |
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57 | 58 | #ifndef EM_BPF |
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58 | 59 | #define EM_BPF 247 |
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.. | .. |
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62 | 63 | #define BPF_FS_MAGIC 0xcafe4a11 |
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63 | 64 | #endif |
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64 | 65 | |
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| 66 | +#define BPF_INSN_SZ (sizeof(struct bpf_insn)) |
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| 67 | + |
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| 68 | +/* vsprintf() in __base_pr() uses nonliteral format string. It may break |
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| 69 | + * compilation if user enables corresponding warning. Disable it explicitly. |
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| 70 | + */ |
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| 71 | +#pragma GCC diagnostic ignored "-Wformat-nonliteral" |
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| 72 | + |
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65 | 73 | #define __printf(a, b) __attribute__((format(printf, a, b))) |
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66 | 74 | |
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67 | | -__printf(1, 2) |
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68 | | -static int __base_pr(const char *format, ...) |
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69 | | -{ |
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70 | | - va_list args; |
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71 | | - int err; |
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| 75 | +static struct bpf_map *bpf_object__add_map(struct bpf_object *obj); |
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| 76 | +static const struct btf_type * |
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| 77 | +skip_mods_and_typedefs(const struct btf *btf, __u32 id, __u32 *res_id); |
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72 | 78 | |
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73 | | - va_start(args, format); |
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74 | | - err = vfprintf(stderr, format, args); |
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75 | | - va_end(args); |
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76 | | - return err; |
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| 79 | +static int __base_pr(enum libbpf_print_level level, const char *format, |
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| 80 | + va_list args) |
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| 81 | +{ |
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| 82 | + if (level == LIBBPF_DEBUG) |
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| 83 | + return 0; |
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| 84 | + |
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| 85 | + return vfprintf(stderr, format, args); |
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77 | 86 | } |
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78 | 87 | |
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79 | | -static __printf(1, 2) libbpf_print_fn_t __pr_warning = __base_pr; |
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80 | | -static __printf(1, 2) libbpf_print_fn_t __pr_info = __base_pr; |
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81 | | -static __printf(1, 2) libbpf_print_fn_t __pr_debug; |
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| 88 | +static libbpf_print_fn_t __libbpf_pr = __base_pr; |
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82 | 89 | |
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83 | | -#define __pr(func, fmt, ...) \ |
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84 | | -do { \ |
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85 | | - if ((func)) \ |
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86 | | - (func)("libbpf: " fmt, ##__VA_ARGS__); \ |
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87 | | -} while (0) |
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88 | | - |
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89 | | -#define pr_warning(fmt, ...) __pr(__pr_warning, fmt, ##__VA_ARGS__) |
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90 | | -#define pr_info(fmt, ...) __pr(__pr_info, fmt, ##__VA_ARGS__) |
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91 | | -#define pr_debug(fmt, ...) __pr(__pr_debug, fmt, ##__VA_ARGS__) |
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92 | | - |
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93 | | -void libbpf_set_print(libbpf_print_fn_t warn, |
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94 | | - libbpf_print_fn_t info, |
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95 | | - libbpf_print_fn_t debug) |
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| 90 | +libbpf_print_fn_t libbpf_set_print(libbpf_print_fn_t fn) |
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96 | 91 | { |
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97 | | - __pr_warning = warn; |
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98 | | - __pr_info = info; |
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99 | | - __pr_debug = debug; |
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| 92 | + libbpf_print_fn_t old_print_fn = __libbpf_pr; |
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| 93 | + |
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| 94 | + __libbpf_pr = fn; |
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| 95 | + return old_print_fn; |
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| 96 | +} |
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| 97 | + |
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| 98 | +__printf(2, 3) |
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| 99 | +void libbpf_print(enum libbpf_print_level level, const char *format, ...) |
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| 100 | +{ |
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| 101 | + va_list args; |
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| 102 | + |
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| 103 | + if (!__libbpf_pr) |
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| 104 | + return; |
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| 105 | + |
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| 106 | + va_start(args, format); |
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| 107 | + __libbpf_pr(level, format, args); |
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| 108 | + va_end(args); |
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| 109 | +} |
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| 110 | + |
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| 111 | +static void pr_perm_msg(int err) |
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| 112 | +{ |
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| 113 | + struct rlimit limit; |
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| 114 | + char buf[100]; |
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| 115 | + |
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| 116 | + if (err != -EPERM || geteuid() != 0) |
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| 117 | + return; |
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| 118 | + |
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| 119 | + err = getrlimit(RLIMIT_MEMLOCK, &limit); |
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| 120 | + if (err) |
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| 121 | + return; |
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| 122 | + |
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| 123 | + if (limit.rlim_cur == RLIM_INFINITY) |
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| 124 | + return; |
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| 125 | + |
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| 126 | + if (limit.rlim_cur < 1024) |
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| 127 | + snprintf(buf, sizeof(buf), "%zu bytes", (size_t)limit.rlim_cur); |
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| 128 | + else if (limit.rlim_cur < 1024*1024) |
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| 129 | + snprintf(buf, sizeof(buf), "%.1f KiB", (double)limit.rlim_cur / 1024); |
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| 130 | + else |
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| 131 | + snprintf(buf, sizeof(buf), "%.1f MiB", (double)limit.rlim_cur / (1024*1024)); |
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| 132 | + |
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| 133 | + pr_warn("permission error while running as root; try raising 'ulimit -l'? current value: %s\n", |
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| 134 | + buf); |
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100 | 135 | } |
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101 | 136 | |
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102 | 137 | #define STRERR_BUFSIZE 128 |
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103 | | - |
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104 | | -#define CHECK_ERR(action, err, out) do { \ |
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105 | | - err = action; \ |
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106 | | - if (err) \ |
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107 | | - goto out; \ |
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108 | | -} while(0) |
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109 | | - |
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110 | 138 | |
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111 | 139 | /* Copied from tools/perf/util/util.h */ |
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112 | 140 | #ifndef zfree |
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.. | .. |
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122 | 150 | ___err; }) |
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123 | 151 | #endif |
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124 | 152 | |
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125 | | -#ifdef HAVE_LIBELF_MMAP_SUPPORT |
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126 | | -# define LIBBPF_ELF_C_READ_MMAP ELF_C_READ_MMAP |
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127 | | -#else |
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128 | | -# define LIBBPF_ELF_C_READ_MMAP ELF_C_READ |
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129 | | -#endif |
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| 153 | +static inline __u64 ptr_to_u64(const void *ptr) |
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| 154 | +{ |
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| 155 | + return (__u64) (unsigned long) ptr; |
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| 156 | +} |
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| 157 | + |
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| 158 | +enum kern_feature_id { |
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| 159 | + /* v4.14: kernel support for program & map names. */ |
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| 160 | + FEAT_PROG_NAME, |
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| 161 | + /* v5.2: kernel support for global data sections. */ |
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| 162 | + FEAT_GLOBAL_DATA, |
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| 163 | + /* BTF support */ |
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| 164 | + FEAT_BTF, |
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| 165 | + /* BTF_KIND_FUNC and BTF_KIND_FUNC_PROTO support */ |
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| 166 | + FEAT_BTF_FUNC, |
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| 167 | + /* BTF_KIND_VAR and BTF_KIND_DATASEC support */ |
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| 168 | + FEAT_BTF_DATASEC, |
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| 169 | + /* BTF_FUNC_GLOBAL is supported */ |
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| 170 | + FEAT_BTF_GLOBAL_FUNC, |
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| 171 | + /* BPF_F_MMAPABLE is supported for arrays */ |
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| 172 | + FEAT_ARRAY_MMAP, |
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| 173 | + /* kernel support for expected_attach_type in BPF_PROG_LOAD */ |
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| 174 | + FEAT_EXP_ATTACH_TYPE, |
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| 175 | + /* bpf_probe_read_{kernel,user}[_str] helpers */ |
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| 176 | + FEAT_PROBE_READ_KERN, |
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| 177 | + /* BPF_PROG_BIND_MAP is supported */ |
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| 178 | + FEAT_PROG_BIND_MAP, |
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| 179 | + __FEAT_CNT, |
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| 180 | +}; |
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| 181 | + |
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| 182 | +static bool kernel_supports(enum kern_feature_id feat_id); |
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| 183 | + |
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| 184 | +enum reloc_type { |
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| 185 | + RELO_LD64, |
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| 186 | + RELO_CALL, |
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| 187 | + RELO_DATA, |
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| 188 | + RELO_EXTERN, |
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| 189 | +}; |
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| 190 | + |
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| 191 | +struct reloc_desc { |
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| 192 | + enum reloc_type type; |
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| 193 | + int insn_idx; |
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| 194 | + int map_idx; |
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| 195 | + int sym_off; |
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| 196 | + bool processed; |
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| 197 | +}; |
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| 198 | + |
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| 199 | +struct bpf_sec_def; |
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| 200 | + |
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| 201 | +typedef struct bpf_link *(*attach_fn_t)(const struct bpf_sec_def *sec, |
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| 202 | + struct bpf_program *prog); |
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| 203 | + |
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| 204 | +struct bpf_sec_def { |
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| 205 | + const char *sec; |
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| 206 | + size_t len; |
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| 207 | + enum bpf_prog_type prog_type; |
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| 208 | + enum bpf_attach_type expected_attach_type; |
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| 209 | + bool is_exp_attach_type_optional; |
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| 210 | + bool is_attachable; |
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| 211 | + bool is_attach_btf; |
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| 212 | + bool is_sleepable; |
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| 213 | + attach_fn_t attach_fn; |
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| 214 | +}; |
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130 | 215 | |
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131 | 216 | /* |
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132 | 217 | * bpf_prog should be a better name but it has been used in |
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133 | 218 | * linux/filter.h. |
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134 | 219 | */ |
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135 | 220 | struct bpf_program { |
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136 | | - /* Index in elf obj file, for relocation use. */ |
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137 | | - int idx; |
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138 | | - char *name; |
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139 | | - int prog_ifindex; |
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140 | | - char *section_name; |
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141 | | - struct bpf_insn *insns; |
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142 | | - size_t insns_cnt, main_prog_cnt; |
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143 | | - enum bpf_prog_type type; |
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| 221 | + const struct bpf_sec_def *sec_def; |
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| 222 | + char *sec_name; |
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| 223 | + size_t sec_idx; |
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| 224 | + /* this program's instruction offset (in number of instructions) |
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| 225 | + * within its containing ELF section |
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| 226 | + */ |
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| 227 | + size_t sec_insn_off; |
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| 228 | + /* number of original instructions in ELF section belonging to this |
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| 229 | + * program, not taking into account subprogram instructions possible |
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| 230 | + * appended later during relocation |
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| 231 | + */ |
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| 232 | + size_t sec_insn_cnt; |
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| 233 | + /* Offset (in number of instructions) of the start of instruction |
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| 234 | + * belonging to this BPF program within its containing main BPF |
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| 235 | + * program. For the entry-point (main) BPF program, this is always |
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| 236 | + * zero. For a sub-program, this gets reset before each of main BPF |
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| 237 | + * programs are processed and relocated and is used to determined |
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| 238 | + * whether sub-program was already appended to the main program, and |
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| 239 | + * if yes, at which instruction offset. |
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| 240 | + */ |
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| 241 | + size_t sub_insn_off; |
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144 | 242 | |
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145 | | - struct reloc_desc { |
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146 | | - enum { |
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147 | | - RELO_LD64, |
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148 | | - RELO_CALL, |
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149 | | - } type; |
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150 | | - int insn_idx; |
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151 | | - union { |
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152 | | - int map_idx; |
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153 | | - int text_off; |
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154 | | - }; |
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155 | | - } *reloc_desc; |
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| 243 | + char *name; |
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| 244 | + /* sec_name with / replaced by _; makes recursive pinning |
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| 245 | + * in bpf_object__pin_programs easier |
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| 246 | + */ |
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| 247 | + char *pin_name; |
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| 248 | + |
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| 249 | + /* instructions that belong to BPF program; insns[0] is located at |
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| 250 | + * sec_insn_off instruction within its ELF section in ELF file, so |
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| 251 | + * when mapping ELF file instruction index to the local instruction, |
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| 252 | + * one needs to subtract sec_insn_off; and vice versa. |
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| 253 | + */ |
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| 254 | + struct bpf_insn *insns; |
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| 255 | + /* actual number of instruction in this BPF program's image; for |
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| 256 | + * entry-point BPF programs this includes the size of main program |
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| 257 | + * itself plus all the used sub-programs, appended at the end |
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| 258 | + */ |
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| 259 | + size_t insns_cnt; |
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| 260 | + |
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| 261 | + struct reloc_desc *reloc_desc; |
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156 | 262 | int nr_reloc; |
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| 263 | + int log_level; |
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157 | 264 | |
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158 | 265 | struct { |
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159 | 266 | int nr; |
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.. | .. |
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165 | 272 | void *priv; |
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166 | 273 | bpf_program_clear_priv_t clear_priv; |
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167 | 274 | |
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| 275 | + bool load; |
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| 276 | + enum bpf_prog_type type; |
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168 | 277 | enum bpf_attach_type expected_attach_type; |
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| 278 | + int prog_ifindex; |
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| 279 | + __u32 attach_btf_id; |
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| 280 | + __u32 attach_prog_fd; |
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| 281 | + void *func_info; |
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| 282 | + __u32 func_info_rec_size; |
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| 283 | + __u32 func_info_cnt; |
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| 284 | + |
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| 285 | + void *line_info; |
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| 286 | + __u32 line_info_rec_size; |
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| 287 | + __u32 line_info_cnt; |
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| 288 | + __u32 prog_flags; |
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| 289 | +}; |
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| 290 | + |
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| 291 | +struct bpf_struct_ops { |
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| 292 | + const char *tname; |
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| 293 | + const struct btf_type *type; |
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| 294 | + struct bpf_program **progs; |
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| 295 | + __u32 *kern_func_off; |
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| 296 | + /* e.g. struct tcp_congestion_ops in bpf_prog's btf format */ |
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| 297 | + void *data; |
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| 298 | + /* e.g. struct bpf_struct_ops_tcp_congestion_ops in |
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| 299 | + * btf_vmlinux's format. |
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| 300 | + * struct bpf_struct_ops_tcp_congestion_ops { |
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| 301 | + * [... some other kernel fields ...] |
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| 302 | + * struct tcp_congestion_ops data; |
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| 303 | + * } |
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| 304 | + * kern_vdata-size == sizeof(struct bpf_struct_ops_tcp_congestion_ops) |
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| 305 | + * bpf_map__init_kern_struct_ops() will populate the "kern_vdata" |
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| 306 | + * from "data". |
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| 307 | + */ |
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| 308 | + void *kern_vdata; |
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| 309 | + __u32 type_id; |
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| 310 | +}; |
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| 311 | + |
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| 312 | +#define DATA_SEC ".data" |
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| 313 | +#define BSS_SEC ".bss" |
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| 314 | +#define RODATA_SEC ".rodata" |
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| 315 | +#define KCONFIG_SEC ".kconfig" |
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| 316 | +#define KSYMS_SEC ".ksyms" |
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| 317 | +#define STRUCT_OPS_SEC ".struct_ops" |
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| 318 | + |
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| 319 | +enum libbpf_map_type { |
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| 320 | + LIBBPF_MAP_UNSPEC, |
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| 321 | + LIBBPF_MAP_DATA, |
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| 322 | + LIBBPF_MAP_BSS, |
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| 323 | + LIBBPF_MAP_RODATA, |
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| 324 | + LIBBPF_MAP_KCONFIG, |
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| 325 | +}; |
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| 326 | + |
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| 327 | +static const char * const libbpf_type_to_btf_name[] = { |
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| 328 | + [LIBBPF_MAP_DATA] = DATA_SEC, |
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| 329 | + [LIBBPF_MAP_BSS] = BSS_SEC, |
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| 330 | + [LIBBPF_MAP_RODATA] = RODATA_SEC, |
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| 331 | + [LIBBPF_MAP_KCONFIG] = KCONFIG_SEC, |
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169 | 332 | }; |
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170 | 333 | |
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171 | 334 | struct bpf_map { |
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172 | | - int fd; |
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173 | 335 | char *name; |
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174 | | - size_t offset; |
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| 336 | + int fd; |
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| 337 | + int sec_idx; |
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| 338 | + size_t sec_offset; |
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175 | 339 | int map_ifindex; |
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| 340 | + int inner_map_fd; |
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176 | 341 | struct bpf_map_def def; |
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| 342 | + __u32 numa_node; |
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| 343 | + __u32 btf_var_idx; |
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177 | 344 | __u32 btf_key_type_id; |
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178 | 345 | __u32 btf_value_type_id; |
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| 346 | + __u32 btf_vmlinux_value_type_id; |
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179 | 347 | void *priv; |
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180 | 348 | bpf_map_clear_priv_t clear_priv; |
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| 349 | + enum libbpf_map_type libbpf_type; |
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| 350 | + void *mmaped; |
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| 351 | + struct bpf_struct_ops *st_ops; |
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| 352 | + struct bpf_map *inner_map; |
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| 353 | + void **init_slots; |
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| 354 | + int init_slots_sz; |
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| 355 | + char *pin_path; |
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| 356 | + bool pinned; |
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| 357 | + bool reused; |
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| 358 | +}; |
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| 359 | + |
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| 360 | +enum extern_type { |
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| 361 | + EXT_UNKNOWN, |
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| 362 | + EXT_KCFG, |
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| 363 | + EXT_KSYM, |
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| 364 | +}; |
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| 365 | + |
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| 366 | +enum kcfg_type { |
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| 367 | + KCFG_UNKNOWN, |
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| 368 | + KCFG_CHAR, |
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| 369 | + KCFG_BOOL, |
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| 370 | + KCFG_INT, |
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| 371 | + KCFG_TRISTATE, |
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| 372 | + KCFG_CHAR_ARR, |
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| 373 | +}; |
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| 374 | + |
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| 375 | +struct extern_desc { |
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| 376 | + enum extern_type type; |
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| 377 | + int sym_idx; |
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| 378 | + int btf_id; |
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| 379 | + int sec_btf_id; |
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| 380 | + const char *name; |
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| 381 | + bool is_set; |
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| 382 | + bool is_weak; |
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| 383 | + union { |
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| 384 | + struct { |
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| 385 | + enum kcfg_type type; |
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| 386 | + int sz; |
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| 387 | + int align; |
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| 388 | + int data_off; |
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| 389 | + bool is_signed; |
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| 390 | + } kcfg; |
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| 391 | + struct { |
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| 392 | + unsigned long long addr; |
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| 393 | + |
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| 394 | + /* target btf_id of the corresponding kernel var. */ |
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| 395 | + int vmlinux_btf_id; |
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| 396 | + |
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| 397 | + /* local btf_id of the ksym extern's type. */ |
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| 398 | + __u32 type_id; |
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| 399 | + } ksym; |
---|
| 400 | + }; |
---|
181 | 401 | }; |
---|
182 | 402 | |
---|
183 | 403 | static LIST_HEAD(bpf_objects_list); |
---|
184 | 404 | |
---|
185 | 405 | struct bpf_object { |
---|
| 406 | + char name[BPF_OBJ_NAME_LEN]; |
---|
186 | 407 | char license[64]; |
---|
187 | | - u32 kern_version; |
---|
| 408 | + __u32 kern_version; |
---|
188 | 409 | |
---|
189 | 410 | struct bpf_program *programs; |
---|
190 | 411 | size_t nr_programs; |
---|
191 | 412 | struct bpf_map *maps; |
---|
192 | 413 | size_t nr_maps; |
---|
| 414 | + size_t maps_cap; |
---|
| 415 | + |
---|
| 416 | + char *kconfig; |
---|
| 417 | + struct extern_desc *externs; |
---|
| 418 | + int nr_extern; |
---|
| 419 | + int kconfig_map_idx; |
---|
| 420 | + int rodata_map_idx; |
---|
193 | 421 | |
---|
194 | 422 | bool loaded; |
---|
195 | | - bool has_pseudo_calls; |
---|
| 423 | + bool has_subcalls; |
---|
196 | 424 | |
---|
197 | 425 | /* |
---|
198 | 426 | * Information when doing elf related work. Only valid if fd |
---|
.. | .. |
---|
200 | 428 | */ |
---|
201 | 429 | struct { |
---|
202 | 430 | int fd; |
---|
203 | | - void *obj_buf; |
---|
| 431 | + const void *obj_buf; |
---|
204 | 432 | size_t obj_buf_sz; |
---|
205 | 433 | Elf *elf; |
---|
206 | 434 | GElf_Ehdr ehdr; |
---|
207 | 435 | Elf_Data *symbols; |
---|
| 436 | + Elf_Data *data; |
---|
| 437 | + Elf_Data *rodata; |
---|
| 438 | + Elf_Data *bss; |
---|
| 439 | + Elf_Data *st_ops_data; |
---|
| 440 | + size_t shstrndx; /* section index for section name strings */ |
---|
208 | 441 | size_t strtabidx; |
---|
209 | 442 | struct { |
---|
210 | 443 | GElf_Shdr shdr; |
---|
211 | 444 | Elf_Data *data; |
---|
212 | | - } *reloc; |
---|
213 | | - int nr_reloc; |
---|
| 445 | + } *reloc_sects; |
---|
| 446 | + int nr_reloc_sects; |
---|
214 | 447 | int maps_shndx; |
---|
| 448 | + int btf_maps_shndx; |
---|
| 449 | + __u32 btf_maps_sec_btf_id; |
---|
215 | 450 | int text_shndx; |
---|
| 451 | + int symbols_shndx; |
---|
| 452 | + int data_shndx; |
---|
| 453 | + int rodata_shndx; |
---|
| 454 | + int bss_shndx; |
---|
| 455 | + int st_ops_shndx; |
---|
216 | 456 | } efile; |
---|
217 | 457 | /* |
---|
218 | 458 | * All loaded bpf_object is linked in a list, which is |
---|
.. | .. |
---|
222 | 462 | struct list_head list; |
---|
223 | 463 | |
---|
224 | 464 | struct btf *btf; |
---|
| 465 | + /* Parse and load BTF vmlinux if any of the programs in the object need |
---|
| 466 | + * it at load time. |
---|
| 467 | + */ |
---|
| 468 | + struct btf *btf_vmlinux; |
---|
| 469 | + struct btf_ext *btf_ext; |
---|
225 | 470 | |
---|
226 | 471 | void *priv; |
---|
227 | 472 | bpf_object_clear_priv_t clear_priv; |
---|
.. | .. |
---|
230 | 475 | }; |
---|
231 | 476 | #define obj_elf_valid(o) ((o)->efile.elf) |
---|
232 | 477 | |
---|
233 | | -static void bpf_program__unload(struct bpf_program *prog) |
---|
| 478 | +static const char *elf_sym_str(const struct bpf_object *obj, size_t off); |
---|
| 479 | +static const char *elf_sec_str(const struct bpf_object *obj, size_t off); |
---|
| 480 | +static Elf_Scn *elf_sec_by_idx(const struct bpf_object *obj, size_t idx); |
---|
| 481 | +static Elf_Scn *elf_sec_by_name(const struct bpf_object *obj, const char *name); |
---|
| 482 | +static int elf_sec_hdr(const struct bpf_object *obj, Elf_Scn *scn, GElf_Shdr *hdr); |
---|
| 483 | +static const char *elf_sec_name(const struct bpf_object *obj, Elf_Scn *scn); |
---|
| 484 | +static Elf_Data *elf_sec_data(const struct bpf_object *obj, Elf_Scn *scn); |
---|
| 485 | +static int elf_sym_by_sec_off(const struct bpf_object *obj, size_t sec_idx, |
---|
| 486 | + size_t off, __u32 sym_type, GElf_Sym *sym); |
---|
| 487 | + |
---|
| 488 | +void bpf_program__unload(struct bpf_program *prog) |
---|
234 | 489 | { |
---|
235 | 490 | int i; |
---|
236 | 491 | |
---|
.. | .. |
---|
245 | 500 | for (i = 0; i < prog->instances.nr; i++) |
---|
246 | 501 | zclose(prog->instances.fds[i]); |
---|
247 | 502 | } else if (prog->instances.nr != -1) { |
---|
248 | | - pr_warning("Internal error: instances.nr is %d\n", |
---|
249 | | - prog->instances.nr); |
---|
| 503 | + pr_warn("Internal error: instances.nr is %d\n", |
---|
| 504 | + prog->instances.nr); |
---|
250 | 505 | } |
---|
251 | 506 | |
---|
252 | 507 | prog->instances.nr = -1; |
---|
253 | 508 | zfree(&prog->instances.fds); |
---|
| 509 | + |
---|
| 510 | + zfree(&prog->func_info); |
---|
| 511 | + zfree(&prog->line_info); |
---|
254 | 512 | } |
---|
255 | 513 | |
---|
256 | 514 | static void bpf_program__exit(struct bpf_program *prog) |
---|
.. | .. |
---|
266 | 524 | |
---|
267 | 525 | bpf_program__unload(prog); |
---|
268 | 526 | zfree(&prog->name); |
---|
269 | | - zfree(&prog->section_name); |
---|
| 527 | + zfree(&prog->sec_name); |
---|
| 528 | + zfree(&prog->pin_name); |
---|
270 | 529 | zfree(&prog->insns); |
---|
271 | 530 | zfree(&prog->reloc_desc); |
---|
272 | 531 | |
---|
273 | 532 | prog->nr_reloc = 0; |
---|
274 | 533 | prog->insns_cnt = 0; |
---|
275 | | - prog->idx = -1; |
---|
| 534 | + prog->sec_idx = -1; |
---|
| 535 | +} |
---|
| 536 | + |
---|
| 537 | +static char *__bpf_program__pin_name(struct bpf_program *prog) |
---|
| 538 | +{ |
---|
| 539 | + char *name, *p; |
---|
| 540 | + |
---|
| 541 | + name = p = strdup(prog->sec_name); |
---|
| 542 | + while ((p = strchr(p, '/'))) |
---|
| 543 | + *p = '_'; |
---|
| 544 | + |
---|
| 545 | + return name; |
---|
| 546 | +} |
---|
| 547 | + |
---|
| 548 | +static bool insn_is_subprog_call(const struct bpf_insn *insn) |
---|
| 549 | +{ |
---|
| 550 | + return BPF_CLASS(insn->code) == BPF_JMP && |
---|
| 551 | + BPF_OP(insn->code) == BPF_CALL && |
---|
| 552 | + BPF_SRC(insn->code) == BPF_K && |
---|
| 553 | + insn->src_reg == BPF_PSEUDO_CALL && |
---|
| 554 | + insn->dst_reg == 0 && |
---|
| 555 | + insn->off == 0; |
---|
276 | 556 | } |
---|
277 | 557 | |
---|
278 | 558 | static int |
---|
279 | | -bpf_program__init(void *data, size_t size, char *section_name, int idx, |
---|
280 | | - struct bpf_program *prog) |
---|
| 559 | +bpf_object__init_prog(struct bpf_object *obj, struct bpf_program *prog, |
---|
| 560 | + const char *name, size_t sec_idx, const char *sec_name, |
---|
| 561 | + size_t sec_off, void *insn_data, size_t insn_data_sz) |
---|
281 | 562 | { |
---|
282 | | - if (size < sizeof(struct bpf_insn)) { |
---|
283 | | - pr_warning("corrupted section '%s'\n", section_name); |
---|
| 563 | + if (insn_data_sz == 0 || insn_data_sz % BPF_INSN_SZ || sec_off % BPF_INSN_SZ) { |
---|
| 564 | + pr_warn("sec '%s': corrupted program '%s', offset %zu, size %zu\n", |
---|
| 565 | + sec_name, name, sec_off, insn_data_sz); |
---|
284 | 566 | return -EINVAL; |
---|
285 | 567 | } |
---|
286 | 568 | |
---|
287 | | - bzero(prog, sizeof(*prog)); |
---|
| 569 | + memset(prog, 0, sizeof(*prog)); |
---|
| 570 | + prog->obj = obj; |
---|
288 | 571 | |
---|
289 | | - prog->section_name = strdup(section_name); |
---|
290 | | - if (!prog->section_name) { |
---|
291 | | - pr_warning("failed to alloc name for prog under section(%d) %s\n", |
---|
292 | | - idx, section_name); |
---|
293 | | - goto errout; |
---|
294 | | - } |
---|
| 572 | + prog->sec_idx = sec_idx; |
---|
| 573 | + prog->sec_insn_off = sec_off / BPF_INSN_SZ; |
---|
| 574 | + prog->sec_insn_cnt = insn_data_sz / BPF_INSN_SZ; |
---|
| 575 | + /* insns_cnt can later be increased by appending used subprograms */ |
---|
| 576 | + prog->insns_cnt = prog->sec_insn_cnt; |
---|
295 | 577 | |
---|
296 | | - prog->insns = malloc(size); |
---|
297 | | - if (!prog->insns) { |
---|
298 | | - pr_warning("failed to alloc insns for prog under section %s\n", |
---|
299 | | - section_name); |
---|
300 | | - goto errout; |
---|
301 | | - } |
---|
302 | | - prog->insns_cnt = size / sizeof(struct bpf_insn); |
---|
303 | | - memcpy(prog->insns, data, |
---|
304 | | - prog->insns_cnt * sizeof(struct bpf_insn)); |
---|
305 | | - prog->idx = idx; |
---|
| 578 | + prog->type = BPF_PROG_TYPE_UNSPEC; |
---|
| 579 | + prog->load = true; |
---|
| 580 | + |
---|
306 | 581 | prog->instances.fds = NULL; |
---|
307 | 582 | prog->instances.nr = -1; |
---|
308 | | - prog->type = BPF_PROG_TYPE_KPROBE; |
---|
| 583 | + |
---|
| 584 | + prog->sec_name = strdup(sec_name); |
---|
| 585 | + if (!prog->sec_name) |
---|
| 586 | + goto errout; |
---|
| 587 | + |
---|
| 588 | + prog->name = strdup(name); |
---|
| 589 | + if (!prog->name) |
---|
| 590 | + goto errout; |
---|
| 591 | + |
---|
| 592 | + prog->pin_name = __bpf_program__pin_name(prog); |
---|
| 593 | + if (!prog->pin_name) |
---|
| 594 | + goto errout; |
---|
| 595 | + |
---|
| 596 | + prog->insns = malloc(insn_data_sz); |
---|
| 597 | + if (!prog->insns) |
---|
| 598 | + goto errout; |
---|
| 599 | + memcpy(prog->insns, insn_data, insn_data_sz); |
---|
309 | 600 | |
---|
310 | 601 | return 0; |
---|
311 | 602 | errout: |
---|
| 603 | + pr_warn("sec '%s': failed to allocate memory for prog '%s'\n", sec_name, name); |
---|
312 | 604 | bpf_program__exit(prog); |
---|
313 | 605 | return -ENOMEM; |
---|
314 | 606 | } |
---|
315 | 607 | |
---|
316 | 608 | static int |
---|
317 | | -bpf_object__add_program(struct bpf_object *obj, void *data, size_t size, |
---|
318 | | - char *section_name, int idx) |
---|
| 609 | +bpf_object__add_programs(struct bpf_object *obj, Elf_Data *sec_data, |
---|
| 610 | + const char *sec_name, int sec_idx) |
---|
319 | 611 | { |
---|
320 | | - struct bpf_program prog, *progs; |
---|
| 612 | + struct bpf_program *prog, *progs; |
---|
| 613 | + void *data = sec_data->d_buf; |
---|
| 614 | + size_t sec_sz = sec_data->d_size, sec_off, prog_sz; |
---|
321 | 615 | int nr_progs, err; |
---|
322 | | - |
---|
323 | | - err = bpf_program__init(data, size, section_name, idx, &prog); |
---|
324 | | - if (err) |
---|
325 | | - return err; |
---|
| 616 | + const char *name; |
---|
| 617 | + GElf_Sym sym; |
---|
326 | 618 | |
---|
327 | 619 | progs = obj->programs; |
---|
328 | 620 | nr_progs = obj->nr_programs; |
---|
| 621 | + sec_off = 0; |
---|
329 | 622 | |
---|
330 | | - progs = reallocarray(progs, nr_progs + 1, sizeof(progs[0])); |
---|
331 | | - if (!progs) { |
---|
332 | | - /* |
---|
333 | | - * In this case the original obj->programs |
---|
334 | | - * is still valid, so don't need special treat for |
---|
335 | | - * bpf_close_object(). |
---|
336 | | - */ |
---|
337 | | - pr_warning("failed to alloc a new program under section '%s'\n", |
---|
338 | | - section_name); |
---|
339 | | - bpf_program__exit(&prog); |
---|
340 | | - return -ENOMEM; |
---|
| 623 | + while (sec_off < sec_sz) { |
---|
| 624 | + if (elf_sym_by_sec_off(obj, sec_idx, sec_off, STT_FUNC, &sym)) { |
---|
| 625 | + pr_warn("sec '%s': failed to find program symbol at offset %zu\n", |
---|
| 626 | + sec_name, sec_off); |
---|
| 627 | + return -LIBBPF_ERRNO__FORMAT; |
---|
| 628 | + } |
---|
| 629 | + |
---|
| 630 | + prog_sz = sym.st_size; |
---|
| 631 | + |
---|
| 632 | + name = elf_sym_str(obj, sym.st_name); |
---|
| 633 | + if (!name) { |
---|
| 634 | + pr_warn("sec '%s': failed to get symbol name for offset %zu\n", |
---|
| 635 | + sec_name, sec_off); |
---|
| 636 | + return -LIBBPF_ERRNO__FORMAT; |
---|
| 637 | + } |
---|
| 638 | + |
---|
| 639 | + if (sec_off + prog_sz > sec_sz) { |
---|
| 640 | + pr_warn("sec '%s': program at offset %zu crosses section boundary\n", |
---|
| 641 | + sec_name, sec_off); |
---|
| 642 | + return -LIBBPF_ERRNO__FORMAT; |
---|
| 643 | + } |
---|
| 644 | + |
---|
| 645 | + pr_debug("sec '%s': found program '%s' at insn offset %zu (%zu bytes), code size %zu insns (%zu bytes)\n", |
---|
| 646 | + sec_name, name, sec_off / BPF_INSN_SZ, sec_off, prog_sz / BPF_INSN_SZ, prog_sz); |
---|
| 647 | + |
---|
| 648 | + progs = libbpf_reallocarray(progs, nr_progs + 1, sizeof(*progs)); |
---|
| 649 | + if (!progs) { |
---|
| 650 | + /* |
---|
| 651 | + * In this case the original obj->programs |
---|
| 652 | + * is still valid, so don't need special treat for |
---|
| 653 | + * bpf_close_object(). |
---|
| 654 | + */ |
---|
| 655 | + pr_warn("sec '%s': failed to alloc memory for new program '%s'\n", |
---|
| 656 | + sec_name, name); |
---|
| 657 | + return -ENOMEM; |
---|
| 658 | + } |
---|
| 659 | + obj->programs = progs; |
---|
| 660 | + |
---|
| 661 | + prog = &progs[nr_progs]; |
---|
| 662 | + |
---|
| 663 | + err = bpf_object__init_prog(obj, prog, name, sec_idx, sec_name, |
---|
| 664 | + sec_off, data + sec_off, prog_sz); |
---|
| 665 | + if (err) |
---|
| 666 | + return err; |
---|
| 667 | + |
---|
| 668 | + nr_progs++; |
---|
| 669 | + obj->nr_programs = nr_progs; |
---|
| 670 | + |
---|
| 671 | + sec_off += prog_sz; |
---|
341 | 672 | } |
---|
342 | 673 | |
---|
343 | | - pr_debug("found program %s\n", prog.section_name); |
---|
344 | | - obj->programs = progs; |
---|
345 | | - obj->nr_programs = nr_progs + 1; |
---|
346 | | - prog.obj = obj; |
---|
347 | | - progs[nr_progs] = prog; |
---|
348 | 674 | return 0; |
---|
349 | 675 | } |
---|
350 | 676 | |
---|
351 | | -static int |
---|
352 | | -bpf_object__init_prog_names(struct bpf_object *obj) |
---|
| 677 | +static __u32 get_kernel_version(void) |
---|
353 | 678 | { |
---|
354 | | - Elf_Data *symbols = obj->efile.symbols; |
---|
355 | | - struct bpf_program *prog; |
---|
356 | | - size_t pi, si; |
---|
| 679 | + __u32 major, minor, patch; |
---|
| 680 | + struct utsname info; |
---|
357 | 681 | |
---|
358 | | - for (pi = 0; pi < obj->nr_programs; pi++) { |
---|
359 | | - const char *name = NULL; |
---|
| 682 | + uname(&info); |
---|
| 683 | + if (sscanf(info.release, "%u.%u.%u", &major, &minor, &patch) != 3) |
---|
| 684 | + return 0; |
---|
| 685 | + return KERNEL_VERSION(major, minor, patch); |
---|
| 686 | +} |
---|
360 | 687 | |
---|
361 | | - prog = &obj->programs[pi]; |
---|
| 688 | +static const struct btf_member * |
---|
| 689 | +find_member_by_offset(const struct btf_type *t, __u32 bit_offset) |
---|
| 690 | +{ |
---|
| 691 | + struct btf_member *m; |
---|
| 692 | + int i; |
---|
362 | 693 | |
---|
363 | | - for (si = 0; si < symbols->d_size / sizeof(GElf_Sym) && !name; |
---|
364 | | - si++) { |
---|
365 | | - GElf_Sym sym; |
---|
| 694 | + for (i = 0, m = btf_members(t); i < btf_vlen(t); i++, m++) { |
---|
| 695 | + if (btf_member_bit_offset(t, i) == bit_offset) |
---|
| 696 | + return m; |
---|
| 697 | + } |
---|
366 | 698 | |
---|
367 | | - if (!gelf_getsym(symbols, si, &sym)) |
---|
368 | | - continue; |
---|
369 | | - if (sym.st_shndx != prog->idx) |
---|
370 | | - continue; |
---|
371 | | - if (GELF_ST_BIND(sym.st_info) != STB_GLOBAL) |
---|
372 | | - continue; |
---|
| 699 | + return NULL; |
---|
| 700 | +} |
---|
373 | 701 | |
---|
374 | | - name = elf_strptr(obj->efile.elf, |
---|
375 | | - obj->efile.strtabidx, |
---|
376 | | - sym.st_name); |
---|
377 | | - if (!name) { |
---|
378 | | - pr_warning("failed to get sym name string for prog %s\n", |
---|
379 | | - prog->section_name); |
---|
380 | | - return -LIBBPF_ERRNO__LIBELF; |
---|
381 | | - } |
---|
| 702 | +static const struct btf_member * |
---|
| 703 | +find_member_by_name(const struct btf *btf, const struct btf_type *t, |
---|
| 704 | + const char *name) |
---|
| 705 | +{ |
---|
| 706 | + struct btf_member *m; |
---|
| 707 | + int i; |
---|
| 708 | + |
---|
| 709 | + for (i = 0, m = btf_members(t); i < btf_vlen(t); i++, m++) { |
---|
| 710 | + if (!strcmp(btf__name_by_offset(btf, m->name_off), name)) |
---|
| 711 | + return m; |
---|
| 712 | + } |
---|
| 713 | + |
---|
| 714 | + return NULL; |
---|
| 715 | +} |
---|
| 716 | + |
---|
| 717 | +#define STRUCT_OPS_VALUE_PREFIX "bpf_struct_ops_" |
---|
| 718 | +static int find_btf_by_prefix_kind(const struct btf *btf, const char *prefix, |
---|
| 719 | + const char *name, __u32 kind); |
---|
| 720 | + |
---|
| 721 | +static int |
---|
| 722 | +find_struct_ops_kern_types(const struct btf *btf, const char *tname, |
---|
| 723 | + const struct btf_type **type, __u32 *type_id, |
---|
| 724 | + const struct btf_type **vtype, __u32 *vtype_id, |
---|
| 725 | + const struct btf_member **data_member) |
---|
| 726 | +{ |
---|
| 727 | + const struct btf_type *kern_type, *kern_vtype; |
---|
| 728 | + const struct btf_member *kern_data_member; |
---|
| 729 | + __s32 kern_vtype_id, kern_type_id; |
---|
| 730 | + __u32 i; |
---|
| 731 | + |
---|
| 732 | + kern_type_id = btf__find_by_name_kind(btf, tname, BTF_KIND_STRUCT); |
---|
| 733 | + if (kern_type_id < 0) { |
---|
| 734 | + pr_warn("struct_ops init_kern: struct %s is not found in kernel BTF\n", |
---|
| 735 | + tname); |
---|
| 736 | + return kern_type_id; |
---|
| 737 | + } |
---|
| 738 | + kern_type = btf__type_by_id(btf, kern_type_id); |
---|
| 739 | + |
---|
| 740 | + /* Find the corresponding "map_value" type that will be used |
---|
| 741 | + * in map_update(BPF_MAP_TYPE_STRUCT_OPS). For example, |
---|
| 742 | + * find "struct bpf_struct_ops_tcp_congestion_ops" from the |
---|
| 743 | + * btf_vmlinux. |
---|
| 744 | + */ |
---|
| 745 | + kern_vtype_id = find_btf_by_prefix_kind(btf, STRUCT_OPS_VALUE_PREFIX, |
---|
| 746 | + tname, BTF_KIND_STRUCT); |
---|
| 747 | + if (kern_vtype_id < 0) { |
---|
| 748 | + pr_warn("struct_ops init_kern: struct %s%s is not found in kernel BTF\n", |
---|
| 749 | + STRUCT_OPS_VALUE_PREFIX, tname); |
---|
| 750 | + return kern_vtype_id; |
---|
| 751 | + } |
---|
| 752 | + kern_vtype = btf__type_by_id(btf, kern_vtype_id); |
---|
| 753 | + |
---|
| 754 | + /* Find "struct tcp_congestion_ops" from |
---|
| 755 | + * struct bpf_struct_ops_tcp_congestion_ops { |
---|
| 756 | + * [ ... ] |
---|
| 757 | + * struct tcp_congestion_ops data; |
---|
| 758 | + * } |
---|
| 759 | + */ |
---|
| 760 | + kern_data_member = btf_members(kern_vtype); |
---|
| 761 | + for (i = 0; i < btf_vlen(kern_vtype); i++, kern_data_member++) { |
---|
| 762 | + if (kern_data_member->type == kern_type_id) |
---|
| 763 | + break; |
---|
| 764 | + } |
---|
| 765 | + if (i == btf_vlen(kern_vtype)) { |
---|
| 766 | + pr_warn("struct_ops init_kern: struct %s data is not found in struct %s%s\n", |
---|
| 767 | + tname, STRUCT_OPS_VALUE_PREFIX, tname); |
---|
| 768 | + return -EINVAL; |
---|
| 769 | + } |
---|
| 770 | + |
---|
| 771 | + *type = kern_type; |
---|
| 772 | + *type_id = kern_type_id; |
---|
| 773 | + *vtype = kern_vtype; |
---|
| 774 | + *vtype_id = kern_vtype_id; |
---|
| 775 | + *data_member = kern_data_member; |
---|
| 776 | + |
---|
| 777 | + return 0; |
---|
| 778 | +} |
---|
| 779 | + |
---|
| 780 | +static bool bpf_map__is_struct_ops(const struct bpf_map *map) |
---|
| 781 | +{ |
---|
| 782 | + return map->def.type == BPF_MAP_TYPE_STRUCT_OPS; |
---|
| 783 | +} |
---|
| 784 | + |
---|
| 785 | +/* Init the map's fields that depend on kern_btf */ |
---|
| 786 | +static int bpf_map__init_kern_struct_ops(struct bpf_map *map, |
---|
| 787 | + const struct btf *btf, |
---|
| 788 | + const struct btf *kern_btf) |
---|
| 789 | +{ |
---|
| 790 | + const struct btf_member *member, *kern_member, *kern_data_member; |
---|
| 791 | + const struct btf_type *type, *kern_type, *kern_vtype; |
---|
| 792 | + __u32 i, kern_type_id, kern_vtype_id, kern_data_off; |
---|
| 793 | + struct bpf_struct_ops *st_ops; |
---|
| 794 | + void *data, *kern_data; |
---|
| 795 | + const char *tname; |
---|
| 796 | + int err; |
---|
| 797 | + |
---|
| 798 | + st_ops = map->st_ops; |
---|
| 799 | + type = st_ops->type; |
---|
| 800 | + tname = st_ops->tname; |
---|
| 801 | + err = find_struct_ops_kern_types(kern_btf, tname, |
---|
| 802 | + &kern_type, &kern_type_id, |
---|
| 803 | + &kern_vtype, &kern_vtype_id, |
---|
| 804 | + &kern_data_member); |
---|
| 805 | + if (err) |
---|
| 806 | + return err; |
---|
| 807 | + |
---|
| 808 | + pr_debug("struct_ops init_kern %s: type_id:%u kern_type_id:%u kern_vtype_id:%u\n", |
---|
| 809 | + map->name, st_ops->type_id, kern_type_id, kern_vtype_id); |
---|
| 810 | + |
---|
| 811 | + map->def.value_size = kern_vtype->size; |
---|
| 812 | + map->btf_vmlinux_value_type_id = kern_vtype_id; |
---|
| 813 | + |
---|
| 814 | + st_ops->kern_vdata = calloc(1, kern_vtype->size); |
---|
| 815 | + if (!st_ops->kern_vdata) |
---|
| 816 | + return -ENOMEM; |
---|
| 817 | + |
---|
| 818 | + data = st_ops->data; |
---|
| 819 | + kern_data_off = kern_data_member->offset / 8; |
---|
| 820 | + kern_data = st_ops->kern_vdata + kern_data_off; |
---|
| 821 | + |
---|
| 822 | + member = btf_members(type); |
---|
| 823 | + for (i = 0; i < btf_vlen(type); i++, member++) { |
---|
| 824 | + const struct btf_type *mtype, *kern_mtype; |
---|
| 825 | + __u32 mtype_id, kern_mtype_id; |
---|
| 826 | + void *mdata, *kern_mdata; |
---|
| 827 | + __s64 msize, kern_msize; |
---|
| 828 | + __u32 moff, kern_moff; |
---|
| 829 | + __u32 kern_member_idx; |
---|
| 830 | + const char *mname; |
---|
| 831 | + |
---|
| 832 | + mname = btf__name_by_offset(btf, member->name_off); |
---|
| 833 | + kern_member = find_member_by_name(kern_btf, kern_type, mname); |
---|
| 834 | + if (!kern_member) { |
---|
| 835 | + pr_warn("struct_ops init_kern %s: Cannot find member %s in kernel BTF\n", |
---|
| 836 | + map->name, mname); |
---|
| 837 | + return -ENOTSUP; |
---|
382 | 838 | } |
---|
383 | 839 | |
---|
384 | | - if (!name && prog->idx == obj->efile.text_shndx) |
---|
385 | | - name = ".text"; |
---|
| 840 | + kern_member_idx = kern_member - btf_members(kern_type); |
---|
| 841 | + if (btf_member_bitfield_size(type, i) || |
---|
| 842 | + btf_member_bitfield_size(kern_type, kern_member_idx)) { |
---|
| 843 | + pr_warn("struct_ops init_kern %s: bitfield %s is not supported\n", |
---|
| 844 | + map->name, mname); |
---|
| 845 | + return -ENOTSUP; |
---|
| 846 | + } |
---|
386 | 847 | |
---|
387 | | - if (!name) { |
---|
388 | | - pr_warning("failed to find sym for prog %s\n", |
---|
389 | | - prog->section_name); |
---|
| 848 | + moff = member->offset / 8; |
---|
| 849 | + kern_moff = kern_member->offset / 8; |
---|
| 850 | + |
---|
| 851 | + mdata = data + moff; |
---|
| 852 | + kern_mdata = kern_data + kern_moff; |
---|
| 853 | + |
---|
| 854 | + mtype = skip_mods_and_typedefs(btf, member->type, &mtype_id); |
---|
| 855 | + kern_mtype = skip_mods_and_typedefs(kern_btf, kern_member->type, |
---|
| 856 | + &kern_mtype_id); |
---|
| 857 | + if (BTF_INFO_KIND(mtype->info) != |
---|
| 858 | + BTF_INFO_KIND(kern_mtype->info)) { |
---|
| 859 | + pr_warn("struct_ops init_kern %s: Unmatched member type %s %u != %u(kernel)\n", |
---|
| 860 | + map->name, mname, BTF_INFO_KIND(mtype->info), |
---|
| 861 | + BTF_INFO_KIND(kern_mtype->info)); |
---|
| 862 | + return -ENOTSUP; |
---|
| 863 | + } |
---|
| 864 | + |
---|
| 865 | + if (btf_is_ptr(mtype)) { |
---|
| 866 | + struct bpf_program *prog; |
---|
| 867 | + |
---|
| 868 | + prog = st_ops->progs[i]; |
---|
| 869 | + if (!prog) |
---|
| 870 | + continue; |
---|
| 871 | + |
---|
| 872 | + kern_mtype = skip_mods_and_typedefs(kern_btf, |
---|
| 873 | + kern_mtype->type, |
---|
| 874 | + &kern_mtype_id); |
---|
| 875 | + |
---|
| 876 | + /* mtype->type must be a func_proto which was |
---|
| 877 | + * guaranteed in bpf_object__collect_st_ops_relos(), |
---|
| 878 | + * so only check kern_mtype for func_proto here. |
---|
| 879 | + */ |
---|
| 880 | + if (!btf_is_func_proto(kern_mtype)) { |
---|
| 881 | + pr_warn("struct_ops init_kern %s: kernel member %s is not a func ptr\n", |
---|
| 882 | + map->name, mname); |
---|
| 883 | + return -ENOTSUP; |
---|
| 884 | + } |
---|
| 885 | + |
---|
| 886 | + prog->attach_btf_id = kern_type_id; |
---|
| 887 | + prog->expected_attach_type = kern_member_idx; |
---|
| 888 | + |
---|
| 889 | + st_ops->kern_func_off[i] = kern_data_off + kern_moff; |
---|
| 890 | + |
---|
| 891 | + pr_debug("struct_ops init_kern %s: func ptr %s is set to prog %s from data(+%u) to kern_data(+%u)\n", |
---|
| 892 | + map->name, mname, prog->name, moff, |
---|
| 893 | + kern_moff); |
---|
| 894 | + |
---|
| 895 | + continue; |
---|
| 896 | + } |
---|
| 897 | + |
---|
| 898 | + msize = btf__resolve_size(btf, mtype_id); |
---|
| 899 | + kern_msize = btf__resolve_size(kern_btf, kern_mtype_id); |
---|
| 900 | + if (msize < 0 || kern_msize < 0 || msize != kern_msize) { |
---|
| 901 | + pr_warn("struct_ops init_kern %s: Error in size of member %s: %zd != %zd(kernel)\n", |
---|
| 902 | + map->name, mname, (ssize_t)msize, |
---|
| 903 | + (ssize_t)kern_msize); |
---|
| 904 | + return -ENOTSUP; |
---|
| 905 | + } |
---|
| 906 | + |
---|
| 907 | + pr_debug("struct_ops init_kern %s: copy %s %u bytes from data(+%u) to kern_data(+%u)\n", |
---|
| 908 | + map->name, mname, (unsigned int)msize, |
---|
| 909 | + moff, kern_moff); |
---|
| 910 | + memcpy(kern_mdata, mdata, msize); |
---|
| 911 | + } |
---|
| 912 | + |
---|
| 913 | + return 0; |
---|
| 914 | +} |
---|
| 915 | + |
---|
| 916 | +static int bpf_object__init_kern_struct_ops_maps(struct bpf_object *obj) |
---|
| 917 | +{ |
---|
| 918 | + struct bpf_map *map; |
---|
| 919 | + size_t i; |
---|
| 920 | + int err; |
---|
| 921 | + |
---|
| 922 | + for (i = 0; i < obj->nr_maps; i++) { |
---|
| 923 | + map = &obj->maps[i]; |
---|
| 924 | + |
---|
| 925 | + if (!bpf_map__is_struct_ops(map)) |
---|
| 926 | + continue; |
---|
| 927 | + |
---|
| 928 | + err = bpf_map__init_kern_struct_ops(map, obj->btf, |
---|
| 929 | + obj->btf_vmlinux); |
---|
| 930 | + if (err) |
---|
| 931 | + return err; |
---|
| 932 | + } |
---|
| 933 | + |
---|
| 934 | + return 0; |
---|
| 935 | +} |
---|
| 936 | + |
---|
| 937 | +static int bpf_object__init_struct_ops_maps(struct bpf_object *obj) |
---|
| 938 | +{ |
---|
| 939 | + const struct btf_type *type, *datasec; |
---|
| 940 | + const struct btf_var_secinfo *vsi; |
---|
| 941 | + struct bpf_struct_ops *st_ops; |
---|
| 942 | + const char *tname, *var_name; |
---|
| 943 | + __s32 type_id, datasec_id; |
---|
| 944 | + const struct btf *btf; |
---|
| 945 | + struct bpf_map *map; |
---|
| 946 | + __u32 i; |
---|
| 947 | + |
---|
| 948 | + if (obj->efile.st_ops_shndx == -1) |
---|
| 949 | + return 0; |
---|
| 950 | + |
---|
| 951 | + btf = obj->btf; |
---|
| 952 | + datasec_id = btf__find_by_name_kind(btf, STRUCT_OPS_SEC, |
---|
| 953 | + BTF_KIND_DATASEC); |
---|
| 954 | + if (datasec_id < 0) { |
---|
| 955 | + pr_warn("struct_ops init: DATASEC %s not found\n", |
---|
| 956 | + STRUCT_OPS_SEC); |
---|
| 957 | + return -EINVAL; |
---|
| 958 | + } |
---|
| 959 | + |
---|
| 960 | + datasec = btf__type_by_id(btf, datasec_id); |
---|
| 961 | + vsi = btf_var_secinfos(datasec); |
---|
| 962 | + for (i = 0; i < btf_vlen(datasec); i++, vsi++) { |
---|
| 963 | + type = btf__type_by_id(obj->btf, vsi->type); |
---|
| 964 | + var_name = btf__name_by_offset(obj->btf, type->name_off); |
---|
| 965 | + |
---|
| 966 | + type_id = btf__resolve_type(obj->btf, vsi->type); |
---|
| 967 | + if (type_id < 0) { |
---|
| 968 | + pr_warn("struct_ops init: Cannot resolve var type_id %u in DATASEC %s\n", |
---|
| 969 | + vsi->type, STRUCT_OPS_SEC); |
---|
390 | 970 | return -EINVAL; |
---|
391 | 971 | } |
---|
392 | 972 | |
---|
393 | | - prog->name = strdup(name); |
---|
394 | | - if (!prog->name) { |
---|
395 | | - pr_warning("failed to allocate memory for prog sym %s\n", |
---|
396 | | - name); |
---|
397 | | - return -ENOMEM; |
---|
| 973 | + type = btf__type_by_id(obj->btf, type_id); |
---|
| 974 | + tname = btf__name_by_offset(obj->btf, type->name_off); |
---|
| 975 | + if (!tname[0]) { |
---|
| 976 | + pr_warn("struct_ops init: anonymous type is not supported\n"); |
---|
| 977 | + return -ENOTSUP; |
---|
398 | 978 | } |
---|
| 979 | + if (!btf_is_struct(type)) { |
---|
| 980 | + pr_warn("struct_ops init: %s is not a struct\n", tname); |
---|
| 981 | + return -EINVAL; |
---|
| 982 | + } |
---|
| 983 | + |
---|
| 984 | + map = bpf_object__add_map(obj); |
---|
| 985 | + if (IS_ERR(map)) |
---|
| 986 | + return PTR_ERR(map); |
---|
| 987 | + |
---|
| 988 | + map->sec_idx = obj->efile.st_ops_shndx; |
---|
| 989 | + map->sec_offset = vsi->offset; |
---|
| 990 | + map->name = strdup(var_name); |
---|
| 991 | + if (!map->name) |
---|
| 992 | + return -ENOMEM; |
---|
| 993 | + |
---|
| 994 | + map->def.type = BPF_MAP_TYPE_STRUCT_OPS; |
---|
| 995 | + map->def.key_size = sizeof(int); |
---|
| 996 | + map->def.value_size = type->size; |
---|
| 997 | + map->def.max_entries = 1; |
---|
| 998 | + |
---|
| 999 | + map->st_ops = calloc(1, sizeof(*map->st_ops)); |
---|
| 1000 | + if (!map->st_ops) |
---|
| 1001 | + return -ENOMEM; |
---|
| 1002 | + st_ops = map->st_ops; |
---|
| 1003 | + st_ops->data = malloc(type->size); |
---|
| 1004 | + st_ops->progs = calloc(btf_vlen(type), sizeof(*st_ops->progs)); |
---|
| 1005 | + st_ops->kern_func_off = malloc(btf_vlen(type) * |
---|
| 1006 | + sizeof(*st_ops->kern_func_off)); |
---|
| 1007 | + if (!st_ops->data || !st_ops->progs || !st_ops->kern_func_off) |
---|
| 1008 | + return -ENOMEM; |
---|
| 1009 | + |
---|
| 1010 | + if (vsi->offset + type->size > obj->efile.st_ops_data->d_size) { |
---|
| 1011 | + pr_warn("struct_ops init: var %s is beyond the end of DATASEC %s\n", |
---|
| 1012 | + var_name, STRUCT_OPS_SEC); |
---|
| 1013 | + return -EINVAL; |
---|
| 1014 | + } |
---|
| 1015 | + |
---|
| 1016 | + memcpy(st_ops->data, |
---|
| 1017 | + obj->efile.st_ops_data->d_buf + vsi->offset, |
---|
| 1018 | + type->size); |
---|
| 1019 | + st_ops->tname = tname; |
---|
| 1020 | + st_ops->type = type; |
---|
| 1021 | + st_ops->type_id = type_id; |
---|
| 1022 | + |
---|
| 1023 | + pr_debug("struct_ops init: struct %s(type_id=%u) %s found at offset %u\n", |
---|
| 1024 | + tname, type_id, var_name, vsi->offset); |
---|
399 | 1025 | } |
---|
400 | 1026 | |
---|
401 | 1027 | return 0; |
---|
402 | 1028 | } |
---|
403 | 1029 | |
---|
404 | 1030 | static struct bpf_object *bpf_object__new(const char *path, |
---|
405 | | - void *obj_buf, |
---|
406 | | - size_t obj_buf_sz) |
---|
| 1031 | + const void *obj_buf, |
---|
| 1032 | + size_t obj_buf_sz, |
---|
| 1033 | + const char *obj_name) |
---|
407 | 1034 | { |
---|
408 | 1035 | struct bpf_object *obj; |
---|
| 1036 | + char *end; |
---|
409 | 1037 | |
---|
410 | 1038 | obj = calloc(1, sizeof(struct bpf_object) + strlen(path) + 1); |
---|
411 | 1039 | if (!obj) { |
---|
412 | | - pr_warning("alloc memory failed for %s\n", path); |
---|
| 1040 | + pr_warn("alloc memory failed for %s\n", path); |
---|
413 | 1041 | return ERR_PTR(-ENOMEM); |
---|
414 | 1042 | } |
---|
415 | 1043 | |
---|
416 | 1044 | strcpy(obj->path, path); |
---|
417 | | - obj->efile.fd = -1; |
---|
| 1045 | + if (obj_name) { |
---|
| 1046 | + strncpy(obj->name, obj_name, sizeof(obj->name) - 1); |
---|
| 1047 | + obj->name[sizeof(obj->name) - 1] = 0; |
---|
| 1048 | + } else { |
---|
| 1049 | + /* Using basename() GNU version which doesn't modify arg. */ |
---|
| 1050 | + strncpy(obj->name, basename((void *)path), |
---|
| 1051 | + sizeof(obj->name) - 1); |
---|
| 1052 | + end = strchr(obj->name, '.'); |
---|
| 1053 | + if (end) |
---|
| 1054 | + *end = 0; |
---|
| 1055 | + } |
---|
418 | 1056 | |
---|
| 1057 | + obj->efile.fd = -1; |
---|
419 | 1058 | /* |
---|
420 | | - * Caller of this function should also calls |
---|
| 1059 | + * Caller of this function should also call |
---|
421 | 1060 | * bpf_object__elf_finish() after data collection to return |
---|
422 | 1061 | * obj_buf to user. If not, we should duplicate the buffer to |
---|
423 | 1062 | * avoid user freeing them before elf finish. |
---|
.. | .. |
---|
425 | 1064 | obj->efile.obj_buf = obj_buf; |
---|
426 | 1065 | obj->efile.obj_buf_sz = obj_buf_sz; |
---|
427 | 1066 | obj->efile.maps_shndx = -1; |
---|
| 1067 | + obj->efile.btf_maps_shndx = -1; |
---|
| 1068 | + obj->efile.data_shndx = -1; |
---|
| 1069 | + obj->efile.rodata_shndx = -1; |
---|
| 1070 | + obj->efile.bss_shndx = -1; |
---|
| 1071 | + obj->efile.st_ops_shndx = -1; |
---|
| 1072 | + obj->kconfig_map_idx = -1; |
---|
| 1073 | + obj->rodata_map_idx = -1; |
---|
428 | 1074 | |
---|
| 1075 | + obj->kern_version = get_kernel_version(); |
---|
429 | 1076 | obj->loaded = false; |
---|
430 | 1077 | |
---|
431 | 1078 | INIT_LIST_HEAD(&obj->list); |
---|
.. | .. |
---|
443 | 1090 | obj->efile.elf = NULL; |
---|
444 | 1091 | } |
---|
445 | 1092 | obj->efile.symbols = NULL; |
---|
| 1093 | + obj->efile.data = NULL; |
---|
| 1094 | + obj->efile.rodata = NULL; |
---|
| 1095 | + obj->efile.bss = NULL; |
---|
| 1096 | + obj->efile.st_ops_data = NULL; |
---|
446 | 1097 | |
---|
447 | | - zfree(&obj->efile.reloc); |
---|
448 | | - obj->efile.nr_reloc = 0; |
---|
| 1098 | + zfree(&obj->efile.reloc_sects); |
---|
| 1099 | + obj->efile.nr_reloc_sects = 0; |
---|
449 | 1100 | zclose(obj->efile.fd); |
---|
450 | 1101 | obj->efile.obj_buf = NULL; |
---|
451 | 1102 | obj->efile.obj_buf_sz = 0; |
---|
452 | 1103 | } |
---|
| 1104 | + |
---|
| 1105 | +/* if libelf is old and doesn't support mmap(), fall back to read() */ |
---|
| 1106 | +#ifndef ELF_C_READ_MMAP |
---|
| 1107 | +#define ELF_C_READ_MMAP ELF_C_READ |
---|
| 1108 | +#endif |
---|
453 | 1109 | |
---|
454 | 1110 | static int bpf_object__elf_init(struct bpf_object *obj) |
---|
455 | 1111 | { |
---|
.. | .. |
---|
457 | 1113 | GElf_Ehdr *ep; |
---|
458 | 1114 | |
---|
459 | 1115 | if (obj_elf_valid(obj)) { |
---|
460 | | - pr_warning("elf init: internal error\n"); |
---|
| 1116 | + pr_warn("elf: init internal error\n"); |
---|
461 | 1117 | return -LIBBPF_ERRNO__LIBELF; |
---|
462 | 1118 | } |
---|
463 | 1119 | |
---|
.. | .. |
---|
466 | 1122 | * obj_buf should have been validated by |
---|
467 | 1123 | * bpf_object__open_buffer(). |
---|
468 | 1124 | */ |
---|
469 | | - obj->efile.elf = elf_memory(obj->efile.obj_buf, |
---|
| 1125 | + obj->efile.elf = elf_memory((char *)obj->efile.obj_buf, |
---|
470 | 1126 | obj->efile.obj_buf_sz); |
---|
471 | 1127 | } else { |
---|
472 | 1128 | obj->efile.fd = open(obj->path, O_RDONLY); |
---|
473 | 1129 | if (obj->efile.fd < 0) { |
---|
474 | | - char errmsg[STRERR_BUFSIZE]; |
---|
475 | | - char *cp = str_error(errno, errmsg, sizeof(errmsg)); |
---|
| 1130 | + char errmsg[STRERR_BUFSIZE], *cp; |
---|
476 | 1131 | |
---|
477 | | - pr_warning("failed to open %s: %s\n", obj->path, cp); |
---|
478 | | - return -errno; |
---|
| 1132 | + err = -errno; |
---|
| 1133 | + cp = libbpf_strerror_r(err, errmsg, sizeof(errmsg)); |
---|
| 1134 | + pr_warn("elf: failed to open %s: %s\n", obj->path, cp); |
---|
| 1135 | + return err; |
---|
479 | 1136 | } |
---|
480 | 1137 | |
---|
481 | | - obj->efile.elf = elf_begin(obj->efile.fd, |
---|
482 | | - LIBBPF_ELF_C_READ_MMAP, |
---|
483 | | - NULL); |
---|
| 1138 | + obj->efile.elf = elf_begin(obj->efile.fd, ELF_C_READ_MMAP, NULL); |
---|
484 | 1139 | } |
---|
485 | 1140 | |
---|
486 | 1141 | if (!obj->efile.elf) { |
---|
487 | | - pr_warning("failed to open %s as ELF file\n", |
---|
488 | | - obj->path); |
---|
| 1142 | + pr_warn("elf: failed to open %s as ELF file: %s\n", obj->path, elf_errmsg(-1)); |
---|
489 | 1143 | err = -LIBBPF_ERRNO__LIBELF; |
---|
490 | 1144 | goto errout; |
---|
491 | 1145 | } |
---|
492 | 1146 | |
---|
493 | 1147 | if (!gelf_getehdr(obj->efile.elf, &obj->efile.ehdr)) { |
---|
494 | | - pr_warning("failed to get EHDR from %s\n", |
---|
495 | | - obj->path); |
---|
| 1148 | + pr_warn("elf: failed to get ELF header from %s: %s\n", obj->path, elf_errmsg(-1)); |
---|
496 | 1149 | err = -LIBBPF_ERRNO__FORMAT; |
---|
497 | 1150 | goto errout; |
---|
498 | 1151 | } |
---|
499 | 1152 | ep = &obj->efile.ehdr; |
---|
500 | 1153 | |
---|
| 1154 | + if (elf_getshdrstrndx(obj->efile.elf, &obj->efile.shstrndx)) { |
---|
| 1155 | + pr_warn("elf: failed to get section names section index for %s: %s\n", |
---|
| 1156 | + obj->path, elf_errmsg(-1)); |
---|
| 1157 | + err = -LIBBPF_ERRNO__FORMAT; |
---|
| 1158 | + goto errout; |
---|
| 1159 | + } |
---|
| 1160 | + |
---|
| 1161 | + /* Elf is corrupted/truncated, avoid calling elf_strptr. */ |
---|
| 1162 | + if (!elf_rawdata(elf_getscn(obj->efile.elf, obj->efile.shstrndx), NULL)) { |
---|
| 1163 | + pr_warn("elf: failed to get section names strings from %s: %s\n", |
---|
| 1164 | + obj->path, elf_errmsg(-1)); |
---|
| 1165 | + err = -LIBBPF_ERRNO__FORMAT; |
---|
| 1166 | + goto errout; |
---|
| 1167 | + } |
---|
| 1168 | + |
---|
501 | 1169 | /* Old LLVM set e_machine to EM_NONE */ |
---|
502 | | - if ((ep->e_type != ET_REL) || (ep->e_machine && (ep->e_machine != EM_BPF))) { |
---|
503 | | - pr_warning("%s is not an eBPF object file\n", |
---|
504 | | - obj->path); |
---|
| 1170 | + if (ep->e_type != ET_REL || |
---|
| 1171 | + (ep->e_machine && ep->e_machine != EM_BPF)) { |
---|
| 1172 | + pr_warn("elf: %s is not a valid eBPF object file\n", obj->path); |
---|
505 | 1173 | err = -LIBBPF_ERRNO__FORMAT; |
---|
506 | 1174 | goto errout; |
---|
507 | 1175 | } |
---|
.. | .. |
---|
512 | 1180 | return err; |
---|
513 | 1181 | } |
---|
514 | 1182 | |
---|
515 | | -static int |
---|
516 | | -bpf_object__check_endianness(struct bpf_object *obj) |
---|
| 1183 | +static int bpf_object__check_endianness(struct bpf_object *obj) |
---|
517 | 1184 | { |
---|
518 | | - static unsigned int const endian = 1; |
---|
519 | | - |
---|
520 | | - switch (obj->efile.ehdr.e_ident[EI_DATA]) { |
---|
521 | | - case ELFDATA2LSB: |
---|
522 | | - /* We are big endian, BPF obj is little endian. */ |
---|
523 | | - if (*(unsigned char const *)&endian != 1) |
---|
524 | | - goto mismatch; |
---|
525 | | - break; |
---|
526 | | - |
---|
527 | | - case ELFDATA2MSB: |
---|
528 | | - /* We are little endian, BPF obj is big endian. */ |
---|
529 | | - if (*(unsigned char const *)&endian != 0) |
---|
530 | | - goto mismatch; |
---|
531 | | - break; |
---|
532 | | - default: |
---|
533 | | - return -LIBBPF_ERRNO__ENDIAN; |
---|
534 | | - } |
---|
535 | | - |
---|
536 | | - return 0; |
---|
537 | | - |
---|
538 | | -mismatch: |
---|
539 | | - pr_warning("Error: endianness mismatch.\n"); |
---|
| 1185 | +#if __BYTE_ORDER == __LITTLE_ENDIAN |
---|
| 1186 | + if (obj->efile.ehdr.e_ident[EI_DATA] == ELFDATA2LSB) |
---|
| 1187 | + return 0; |
---|
| 1188 | +#elif __BYTE_ORDER == __BIG_ENDIAN |
---|
| 1189 | + if (obj->efile.ehdr.e_ident[EI_DATA] == ELFDATA2MSB) |
---|
| 1190 | + return 0; |
---|
| 1191 | +#else |
---|
| 1192 | +# error "Unrecognized __BYTE_ORDER__" |
---|
| 1193 | +#endif |
---|
| 1194 | + pr_warn("elf: endianness mismatch in %s.\n", obj->path); |
---|
540 | 1195 | return -LIBBPF_ERRNO__ENDIAN; |
---|
541 | 1196 | } |
---|
542 | 1197 | |
---|
543 | 1198 | static int |
---|
544 | | -bpf_object__init_license(struct bpf_object *obj, |
---|
545 | | - void *data, size_t size) |
---|
| 1199 | +bpf_object__init_license(struct bpf_object *obj, void *data, size_t size) |
---|
546 | 1200 | { |
---|
547 | | - memcpy(obj->license, data, |
---|
548 | | - min(size, sizeof(obj->license) - 1)); |
---|
| 1201 | + memcpy(obj->license, data, min(size, sizeof(obj->license) - 1)); |
---|
549 | 1202 | pr_debug("license of %s is %s\n", obj->path, obj->license); |
---|
550 | 1203 | return 0; |
---|
551 | 1204 | } |
---|
552 | 1205 | |
---|
553 | 1206 | static int |
---|
554 | | -bpf_object__init_kversion(struct bpf_object *obj, |
---|
555 | | - void *data, size_t size) |
---|
| 1207 | +bpf_object__init_kversion(struct bpf_object *obj, void *data, size_t size) |
---|
556 | 1208 | { |
---|
557 | | - u32 kver; |
---|
| 1209 | + __u32 kver; |
---|
558 | 1210 | |
---|
559 | 1211 | if (size != sizeof(kver)) { |
---|
560 | | - pr_warning("invalid kver section in %s\n", obj->path); |
---|
| 1212 | + pr_warn("invalid kver section in %s\n", obj->path); |
---|
561 | 1213 | return -LIBBPF_ERRNO__FORMAT; |
---|
562 | 1214 | } |
---|
563 | 1215 | memcpy(&kver, data, sizeof(kver)); |
---|
564 | 1216 | obj->kern_version = kver; |
---|
565 | | - pr_debug("kernel version of %s is %x\n", obj->path, |
---|
566 | | - obj->kern_version); |
---|
| 1217 | + pr_debug("kernel version of %s is %x\n", obj->path, obj->kern_version); |
---|
567 | 1218 | return 0; |
---|
568 | 1219 | } |
---|
569 | 1220 | |
---|
570 | | -static int compare_bpf_map(const void *_a, const void *_b) |
---|
| 1221 | +static bool bpf_map_type__is_map_in_map(enum bpf_map_type type) |
---|
571 | 1222 | { |
---|
572 | | - const struct bpf_map *a = _a; |
---|
573 | | - const struct bpf_map *b = _b; |
---|
| 1223 | + if (type == BPF_MAP_TYPE_ARRAY_OF_MAPS || |
---|
| 1224 | + type == BPF_MAP_TYPE_HASH_OF_MAPS) |
---|
| 1225 | + return true; |
---|
| 1226 | + return false; |
---|
| 1227 | +} |
---|
574 | 1228 | |
---|
575 | | - return a->offset - b->offset; |
---|
| 1229 | +int bpf_object__section_size(const struct bpf_object *obj, const char *name, |
---|
| 1230 | + __u32 *size) |
---|
| 1231 | +{ |
---|
| 1232 | + int ret = -ENOENT; |
---|
| 1233 | + |
---|
| 1234 | + *size = 0; |
---|
| 1235 | + if (!name) { |
---|
| 1236 | + return -EINVAL; |
---|
| 1237 | + } else if (!strcmp(name, DATA_SEC)) { |
---|
| 1238 | + if (obj->efile.data) |
---|
| 1239 | + *size = obj->efile.data->d_size; |
---|
| 1240 | + } else if (!strcmp(name, BSS_SEC)) { |
---|
| 1241 | + if (obj->efile.bss) |
---|
| 1242 | + *size = obj->efile.bss->d_size; |
---|
| 1243 | + } else if (!strcmp(name, RODATA_SEC)) { |
---|
| 1244 | + if (obj->efile.rodata) |
---|
| 1245 | + *size = obj->efile.rodata->d_size; |
---|
| 1246 | + } else if (!strcmp(name, STRUCT_OPS_SEC)) { |
---|
| 1247 | + if (obj->efile.st_ops_data) |
---|
| 1248 | + *size = obj->efile.st_ops_data->d_size; |
---|
| 1249 | + } else { |
---|
| 1250 | + Elf_Scn *scn = elf_sec_by_name(obj, name); |
---|
| 1251 | + Elf_Data *data = elf_sec_data(obj, scn); |
---|
| 1252 | + |
---|
| 1253 | + if (data) { |
---|
| 1254 | + ret = 0; /* found it */ |
---|
| 1255 | + *size = data->d_size; |
---|
| 1256 | + } |
---|
| 1257 | + } |
---|
| 1258 | + |
---|
| 1259 | + return *size ? 0 : ret; |
---|
| 1260 | +} |
---|
| 1261 | + |
---|
| 1262 | +int bpf_object__variable_offset(const struct bpf_object *obj, const char *name, |
---|
| 1263 | + __u32 *off) |
---|
| 1264 | +{ |
---|
| 1265 | + Elf_Data *symbols = obj->efile.symbols; |
---|
| 1266 | + const char *sname; |
---|
| 1267 | + size_t si; |
---|
| 1268 | + |
---|
| 1269 | + if (!name || !off) |
---|
| 1270 | + return -EINVAL; |
---|
| 1271 | + |
---|
| 1272 | + for (si = 0; si < symbols->d_size / sizeof(GElf_Sym); si++) { |
---|
| 1273 | + GElf_Sym sym; |
---|
| 1274 | + |
---|
| 1275 | + if (!gelf_getsym(symbols, si, &sym)) |
---|
| 1276 | + continue; |
---|
| 1277 | + if (GELF_ST_BIND(sym.st_info) != STB_GLOBAL || |
---|
| 1278 | + GELF_ST_TYPE(sym.st_info) != STT_OBJECT) |
---|
| 1279 | + continue; |
---|
| 1280 | + |
---|
| 1281 | + sname = elf_sym_str(obj, sym.st_name); |
---|
| 1282 | + if (!sname) { |
---|
| 1283 | + pr_warn("failed to get sym name string for var %s\n", |
---|
| 1284 | + name); |
---|
| 1285 | + return -EIO; |
---|
| 1286 | + } |
---|
| 1287 | + if (strcmp(name, sname) == 0) { |
---|
| 1288 | + *off = sym.st_value; |
---|
| 1289 | + return 0; |
---|
| 1290 | + } |
---|
| 1291 | + } |
---|
| 1292 | + |
---|
| 1293 | + return -ENOENT; |
---|
| 1294 | +} |
---|
| 1295 | + |
---|
| 1296 | +static struct bpf_map *bpf_object__add_map(struct bpf_object *obj) |
---|
| 1297 | +{ |
---|
| 1298 | + struct bpf_map *new_maps; |
---|
| 1299 | + size_t new_cap; |
---|
| 1300 | + int i; |
---|
| 1301 | + |
---|
| 1302 | + if (obj->nr_maps < obj->maps_cap) |
---|
| 1303 | + return &obj->maps[obj->nr_maps++]; |
---|
| 1304 | + |
---|
| 1305 | + new_cap = max((size_t)4, obj->maps_cap * 3 / 2); |
---|
| 1306 | + new_maps = libbpf_reallocarray(obj->maps, new_cap, sizeof(*obj->maps)); |
---|
| 1307 | + if (!new_maps) { |
---|
| 1308 | + pr_warn("alloc maps for object failed\n"); |
---|
| 1309 | + return ERR_PTR(-ENOMEM); |
---|
| 1310 | + } |
---|
| 1311 | + |
---|
| 1312 | + obj->maps_cap = new_cap; |
---|
| 1313 | + obj->maps = new_maps; |
---|
| 1314 | + |
---|
| 1315 | + /* zero out new maps */ |
---|
| 1316 | + memset(obj->maps + obj->nr_maps, 0, |
---|
| 1317 | + (obj->maps_cap - obj->nr_maps) * sizeof(*obj->maps)); |
---|
| 1318 | + /* |
---|
| 1319 | + * fill all fd with -1 so won't close incorrect fd (fd=0 is stdin) |
---|
| 1320 | + * when failure (zclose won't close negative fd)). |
---|
| 1321 | + */ |
---|
| 1322 | + for (i = obj->nr_maps; i < obj->maps_cap; i++) { |
---|
| 1323 | + obj->maps[i].fd = -1; |
---|
| 1324 | + obj->maps[i].inner_map_fd = -1; |
---|
| 1325 | + } |
---|
| 1326 | + |
---|
| 1327 | + return &obj->maps[obj->nr_maps++]; |
---|
| 1328 | +} |
---|
| 1329 | + |
---|
| 1330 | +static size_t bpf_map_mmap_sz(const struct bpf_map *map) |
---|
| 1331 | +{ |
---|
| 1332 | + long page_sz = sysconf(_SC_PAGE_SIZE); |
---|
| 1333 | + size_t map_sz; |
---|
| 1334 | + |
---|
| 1335 | + map_sz = (size_t)roundup(map->def.value_size, 8) * map->def.max_entries; |
---|
| 1336 | + map_sz = roundup(map_sz, page_sz); |
---|
| 1337 | + return map_sz; |
---|
| 1338 | +} |
---|
| 1339 | + |
---|
| 1340 | +static char *internal_map_name(struct bpf_object *obj, |
---|
| 1341 | + enum libbpf_map_type type) |
---|
| 1342 | +{ |
---|
| 1343 | + char map_name[BPF_OBJ_NAME_LEN], *p; |
---|
| 1344 | + const char *sfx = libbpf_type_to_btf_name[type]; |
---|
| 1345 | + int sfx_len = max((size_t)7, strlen(sfx)); |
---|
| 1346 | + int pfx_len = min((size_t)BPF_OBJ_NAME_LEN - sfx_len - 1, |
---|
| 1347 | + strlen(obj->name)); |
---|
| 1348 | + |
---|
| 1349 | + snprintf(map_name, sizeof(map_name), "%.*s%.*s", pfx_len, obj->name, |
---|
| 1350 | + sfx_len, libbpf_type_to_btf_name[type]); |
---|
| 1351 | + |
---|
| 1352 | + /* sanitise map name to characters allowed by kernel */ |
---|
| 1353 | + for (p = map_name; *p && p < map_name + sizeof(map_name); p++) |
---|
| 1354 | + if (!isalnum(*p) && *p != '_' && *p != '.') |
---|
| 1355 | + *p = '_'; |
---|
| 1356 | + |
---|
| 1357 | + return strdup(map_name); |
---|
576 | 1358 | } |
---|
577 | 1359 | |
---|
578 | 1360 | static int |
---|
579 | | -bpf_object__init_maps(struct bpf_object *obj) |
---|
| 1361 | +bpf_object__init_internal_map(struct bpf_object *obj, enum libbpf_map_type type, |
---|
| 1362 | + int sec_idx, void *data, size_t data_sz) |
---|
580 | 1363 | { |
---|
581 | | - int i, map_idx, map_def_sz, nr_maps = 0; |
---|
582 | | - Elf_Scn *scn; |
---|
583 | | - Elf_Data *data; |
---|
| 1364 | + struct bpf_map_def *def; |
---|
| 1365 | + struct bpf_map *map; |
---|
| 1366 | + int err; |
---|
| 1367 | + |
---|
| 1368 | + map = bpf_object__add_map(obj); |
---|
| 1369 | + if (IS_ERR(map)) |
---|
| 1370 | + return PTR_ERR(map); |
---|
| 1371 | + |
---|
| 1372 | + map->libbpf_type = type; |
---|
| 1373 | + map->sec_idx = sec_idx; |
---|
| 1374 | + map->sec_offset = 0; |
---|
| 1375 | + map->name = internal_map_name(obj, type); |
---|
| 1376 | + if (!map->name) { |
---|
| 1377 | + pr_warn("failed to alloc map name\n"); |
---|
| 1378 | + return -ENOMEM; |
---|
| 1379 | + } |
---|
| 1380 | + |
---|
| 1381 | + def = &map->def; |
---|
| 1382 | + def->type = BPF_MAP_TYPE_ARRAY; |
---|
| 1383 | + def->key_size = sizeof(int); |
---|
| 1384 | + def->value_size = data_sz; |
---|
| 1385 | + def->max_entries = 1; |
---|
| 1386 | + def->map_flags = type == LIBBPF_MAP_RODATA || type == LIBBPF_MAP_KCONFIG |
---|
| 1387 | + ? BPF_F_RDONLY_PROG : 0; |
---|
| 1388 | + def->map_flags |= BPF_F_MMAPABLE; |
---|
| 1389 | + |
---|
| 1390 | + pr_debug("map '%s' (global data): at sec_idx %d, offset %zu, flags %x.\n", |
---|
| 1391 | + map->name, map->sec_idx, map->sec_offset, def->map_flags); |
---|
| 1392 | + |
---|
| 1393 | + map->mmaped = mmap(NULL, bpf_map_mmap_sz(map), PROT_READ | PROT_WRITE, |
---|
| 1394 | + MAP_SHARED | MAP_ANONYMOUS, -1, 0); |
---|
| 1395 | + if (map->mmaped == MAP_FAILED) { |
---|
| 1396 | + err = -errno; |
---|
| 1397 | + map->mmaped = NULL; |
---|
| 1398 | + pr_warn("failed to alloc map '%s' content buffer: %d\n", |
---|
| 1399 | + map->name, err); |
---|
| 1400 | + zfree(&map->name); |
---|
| 1401 | + return err; |
---|
| 1402 | + } |
---|
| 1403 | + |
---|
| 1404 | + if (data) |
---|
| 1405 | + memcpy(map->mmaped, data, data_sz); |
---|
| 1406 | + |
---|
| 1407 | + pr_debug("map %td is \"%s\"\n", map - obj->maps, map->name); |
---|
| 1408 | + return 0; |
---|
| 1409 | +} |
---|
| 1410 | + |
---|
| 1411 | +static int bpf_object__init_global_data_maps(struct bpf_object *obj) |
---|
| 1412 | +{ |
---|
| 1413 | + int err; |
---|
| 1414 | + |
---|
| 1415 | + /* |
---|
| 1416 | + * Populate obj->maps with libbpf internal maps. |
---|
| 1417 | + */ |
---|
| 1418 | + if (obj->efile.data_shndx >= 0) { |
---|
| 1419 | + err = bpf_object__init_internal_map(obj, LIBBPF_MAP_DATA, |
---|
| 1420 | + obj->efile.data_shndx, |
---|
| 1421 | + obj->efile.data->d_buf, |
---|
| 1422 | + obj->efile.data->d_size); |
---|
| 1423 | + if (err) |
---|
| 1424 | + return err; |
---|
| 1425 | + } |
---|
| 1426 | + if (obj->efile.rodata_shndx >= 0) { |
---|
| 1427 | + err = bpf_object__init_internal_map(obj, LIBBPF_MAP_RODATA, |
---|
| 1428 | + obj->efile.rodata_shndx, |
---|
| 1429 | + obj->efile.rodata->d_buf, |
---|
| 1430 | + obj->efile.rodata->d_size); |
---|
| 1431 | + if (err) |
---|
| 1432 | + return err; |
---|
| 1433 | + |
---|
| 1434 | + obj->rodata_map_idx = obj->nr_maps - 1; |
---|
| 1435 | + } |
---|
| 1436 | + if (obj->efile.bss_shndx >= 0) { |
---|
| 1437 | + err = bpf_object__init_internal_map(obj, LIBBPF_MAP_BSS, |
---|
| 1438 | + obj->efile.bss_shndx, |
---|
| 1439 | + NULL, |
---|
| 1440 | + obj->efile.bss->d_size); |
---|
| 1441 | + if (err) |
---|
| 1442 | + return err; |
---|
| 1443 | + } |
---|
| 1444 | + return 0; |
---|
| 1445 | +} |
---|
| 1446 | + |
---|
| 1447 | + |
---|
| 1448 | +static struct extern_desc *find_extern_by_name(const struct bpf_object *obj, |
---|
| 1449 | + const void *name) |
---|
| 1450 | +{ |
---|
| 1451 | + int i; |
---|
| 1452 | + |
---|
| 1453 | + for (i = 0; i < obj->nr_extern; i++) { |
---|
| 1454 | + if (strcmp(obj->externs[i].name, name) == 0) |
---|
| 1455 | + return &obj->externs[i]; |
---|
| 1456 | + } |
---|
| 1457 | + return NULL; |
---|
| 1458 | +} |
---|
| 1459 | + |
---|
| 1460 | +static int set_kcfg_value_tri(struct extern_desc *ext, void *ext_val, |
---|
| 1461 | + char value) |
---|
| 1462 | +{ |
---|
| 1463 | + switch (ext->kcfg.type) { |
---|
| 1464 | + case KCFG_BOOL: |
---|
| 1465 | + if (value == 'm') { |
---|
| 1466 | + pr_warn("extern (kcfg) %s=%c should be tristate or char\n", |
---|
| 1467 | + ext->name, value); |
---|
| 1468 | + return -EINVAL; |
---|
| 1469 | + } |
---|
| 1470 | + *(bool *)ext_val = value == 'y' ? true : false; |
---|
| 1471 | + break; |
---|
| 1472 | + case KCFG_TRISTATE: |
---|
| 1473 | + if (value == 'y') |
---|
| 1474 | + *(enum libbpf_tristate *)ext_val = TRI_YES; |
---|
| 1475 | + else if (value == 'm') |
---|
| 1476 | + *(enum libbpf_tristate *)ext_val = TRI_MODULE; |
---|
| 1477 | + else /* value == 'n' */ |
---|
| 1478 | + *(enum libbpf_tristate *)ext_val = TRI_NO; |
---|
| 1479 | + break; |
---|
| 1480 | + case KCFG_CHAR: |
---|
| 1481 | + *(char *)ext_val = value; |
---|
| 1482 | + break; |
---|
| 1483 | + case KCFG_UNKNOWN: |
---|
| 1484 | + case KCFG_INT: |
---|
| 1485 | + case KCFG_CHAR_ARR: |
---|
| 1486 | + default: |
---|
| 1487 | + pr_warn("extern (kcfg) %s=%c should be bool, tristate, or char\n", |
---|
| 1488 | + ext->name, value); |
---|
| 1489 | + return -EINVAL; |
---|
| 1490 | + } |
---|
| 1491 | + ext->is_set = true; |
---|
| 1492 | + return 0; |
---|
| 1493 | +} |
---|
| 1494 | + |
---|
| 1495 | +static int set_kcfg_value_str(struct extern_desc *ext, char *ext_val, |
---|
| 1496 | + const char *value) |
---|
| 1497 | +{ |
---|
| 1498 | + size_t len; |
---|
| 1499 | + |
---|
| 1500 | + if (ext->kcfg.type != KCFG_CHAR_ARR) { |
---|
| 1501 | + pr_warn("extern (kcfg) %s=%s should be char array\n", ext->name, value); |
---|
| 1502 | + return -EINVAL; |
---|
| 1503 | + } |
---|
| 1504 | + |
---|
| 1505 | + len = strlen(value); |
---|
| 1506 | + if (value[len - 1] != '"') { |
---|
| 1507 | + pr_warn("extern (kcfg) '%s': invalid string config '%s'\n", |
---|
| 1508 | + ext->name, value); |
---|
| 1509 | + return -EINVAL; |
---|
| 1510 | + } |
---|
| 1511 | + |
---|
| 1512 | + /* strip quotes */ |
---|
| 1513 | + len -= 2; |
---|
| 1514 | + if (len >= ext->kcfg.sz) { |
---|
| 1515 | + pr_warn("extern (kcfg) '%s': long string config %s of (%zu bytes) truncated to %d bytes\n", |
---|
| 1516 | + ext->name, value, len, ext->kcfg.sz - 1); |
---|
| 1517 | + len = ext->kcfg.sz - 1; |
---|
| 1518 | + } |
---|
| 1519 | + memcpy(ext_val, value + 1, len); |
---|
| 1520 | + ext_val[len] = '\0'; |
---|
| 1521 | + ext->is_set = true; |
---|
| 1522 | + return 0; |
---|
| 1523 | +} |
---|
| 1524 | + |
---|
| 1525 | +static int parse_u64(const char *value, __u64 *res) |
---|
| 1526 | +{ |
---|
| 1527 | + char *value_end; |
---|
| 1528 | + int err; |
---|
| 1529 | + |
---|
| 1530 | + errno = 0; |
---|
| 1531 | + *res = strtoull(value, &value_end, 0); |
---|
| 1532 | + if (errno) { |
---|
| 1533 | + err = -errno; |
---|
| 1534 | + pr_warn("failed to parse '%s' as integer: %d\n", value, err); |
---|
| 1535 | + return err; |
---|
| 1536 | + } |
---|
| 1537 | + if (*value_end) { |
---|
| 1538 | + pr_warn("failed to parse '%s' as integer completely\n", value); |
---|
| 1539 | + return -EINVAL; |
---|
| 1540 | + } |
---|
| 1541 | + return 0; |
---|
| 1542 | +} |
---|
| 1543 | + |
---|
| 1544 | +static bool is_kcfg_value_in_range(const struct extern_desc *ext, __u64 v) |
---|
| 1545 | +{ |
---|
| 1546 | + int bit_sz = ext->kcfg.sz * 8; |
---|
| 1547 | + |
---|
| 1548 | + if (ext->kcfg.sz == 8) |
---|
| 1549 | + return true; |
---|
| 1550 | + |
---|
| 1551 | + /* Validate that value stored in u64 fits in integer of `ext->sz` |
---|
| 1552 | + * bytes size without any loss of information. If the target integer |
---|
| 1553 | + * is signed, we rely on the following limits of integer type of |
---|
| 1554 | + * Y bits and subsequent transformation: |
---|
| 1555 | + * |
---|
| 1556 | + * -2^(Y-1) <= X <= 2^(Y-1) - 1 |
---|
| 1557 | + * 0 <= X + 2^(Y-1) <= 2^Y - 1 |
---|
| 1558 | + * 0 <= X + 2^(Y-1) < 2^Y |
---|
| 1559 | + * |
---|
| 1560 | + * For unsigned target integer, check that all the (64 - Y) bits are |
---|
| 1561 | + * zero. |
---|
| 1562 | + */ |
---|
| 1563 | + if (ext->kcfg.is_signed) |
---|
| 1564 | + return v + (1ULL << (bit_sz - 1)) < (1ULL << bit_sz); |
---|
| 1565 | + else |
---|
| 1566 | + return (v >> bit_sz) == 0; |
---|
| 1567 | +} |
---|
| 1568 | + |
---|
| 1569 | +static int set_kcfg_value_num(struct extern_desc *ext, void *ext_val, |
---|
| 1570 | + __u64 value) |
---|
| 1571 | +{ |
---|
| 1572 | + if (ext->kcfg.type != KCFG_INT && ext->kcfg.type != KCFG_CHAR) { |
---|
| 1573 | + pr_warn("extern (kcfg) %s=%llu should be integer\n", |
---|
| 1574 | + ext->name, (unsigned long long)value); |
---|
| 1575 | + return -EINVAL; |
---|
| 1576 | + } |
---|
| 1577 | + if (!is_kcfg_value_in_range(ext, value)) { |
---|
| 1578 | + pr_warn("extern (kcfg) %s=%llu value doesn't fit in %d bytes\n", |
---|
| 1579 | + ext->name, (unsigned long long)value, ext->kcfg.sz); |
---|
| 1580 | + return -ERANGE; |
---|
| 1581 | + } |
---|
| 1582 | + switch (ext->kcfg.sz) { |
---|
| 1583 | + case 1: *(__u8 *)ext_val = value; break; |
---|
| 1584 | + case 2: *(__u16 *)ext_val = value; break; |
---|
| 1585 | + case 4: *(__u32 *)ext_val = value; break; |
---|
| 1586 | + case 8: *(__u64 *)ext_val = value; break; |
---|
| 1587 | + default: |
---|
| 1588 | + return -EINVAL; |
---|
| 1589 | + } |
---|
| 1590 | + ext->is_set = true; |
---|
| 1591 | + return 0; |
---|
| 1592 | +} |
---|
| 1593 | + |
---|
| 1594 | +static int bpf_object__process_kconfig_line(struct bpf_object *obj, |
---|
| 1595 | + char *buf, void *data) |
---|
| 1596 | +{ |
---|
| 1597 | + struct extern_desc *ext; |
---|
| 1598 | + char *sep, *value; |
---|
| 1599 | + int len, err = 0; |
---|
| 1600 | + void *ext_val; |
---|
| 1601 | + __u64 num; |
---|
| 1602 | + |
---|
| 1603 | + if (strncmp(buf, "CONFIG_", 7)) |
---|
| 1604 | + return 0; |
---|
| 1605 | + |
---|
| 1606 | + sep = strchr(buf, '='); |
---|
| 1607 | + if (!sep) { |
---|
| 1608 | + pr_warn("failed to parse '%s': no separator\n", buf); |
---|
| 1609 | + return -EINVAL; |
---|
| 1610 | + } |
---|
| 1611 | + |
---|
| 1612 | + /* Trim ending '\n' */ |
---|
| 1613 | + len = strlen(buf); |
---|
| 1614 | + if (buf[len - 1] == '\n') |
---|
| 1615 | + buf[len - 1] = '\0'; |
---|
| 1616 | + /* Split on '=' and ensure that a value is present. */ |
---|
| 1617 | + *sep = '\0'; |
---|
| 1618 | + if (!sep[1]) { |
---|
| 1619 | + *sep = '='; |
---|
| 1620 | + pr_warn("failed to parse '%s': no value\n", buf); |
---|
| 1621 | + return -EINVAL; |
---|
| 1622 | + } |
---|
| 1623 | + |
---|
| 1624 | + ext = find_extern_by_name(obj, buf); |
---|
| 1625 | + if (!ext || ext->is_set) |
---|
| 1626 | + return 0; |
---|
| 1627 | + |
---|
| 1628 | + ext_val = data + ext->kcfg.data_off; |
---|
| 1629 | + value = sep + 1; |
---|
| 1630 | + |
---|
| 1631 | + switch (*value) { |
---|
| 1632 | + case 'y': case 'n': case 'm': |
---|
| 1633 | + err = set_kcfg_value_tri(ext, ext_val, *value); |
---|
| 1634 | + break; |
---|
| 1635 | + case '"': |
---|
| 1636 | + err = set_kcfg_value_str(ext, ext_val, value); |
---|
| 1637 | + break; |
---|
| 1638 | + default: |
---|
| 1639 | + /* assume integer */ |
---|
| 1640 | + err = parse_u64(value, &num); |
---|
| 1641 | + if (err) { |
---|
| 1642 | + pr_warn("extern (kcfg) %s=%s should be integer\n", |
---|
| 1643 | + ext->name, value); |
---|
| 1644 | + return err; |
---|
| 1645 | + } |
---|
| 1646 | + err = set_kcfg_value_num(ext, ext_val, num); |
---|
| 1647 | + break; |
---|
| 1648 | + } |
---|
| 1649 | + if (err) |
---|
| 1650 | + return err; |
---|
| 1651 | + pr_debug("extern (kcfg) %s=%s\n", ext->name, value); |
---|
| 1652 | + return 0; |
---|
| 1653 | +} |
---|
| 1654 | + |
---|
| 1655 | +static int bpf_object__read_kconfig_file(struct bpf_object *obj, void *data) |
---|
| 1656 | +{ |
---|
| 1657 | + char buf[PATH_MAX]; |
---|
| 1658 | + struct utsname uts; |
---|
| 1659 | + int len, err = 0; |
---|
| 1660 | + gzFile file; |
---|
| 1661 | + |
---|
| 1662 | + uname(&uts); |
---|
| 1663 | + len = snprintf(buf, PATH_MAX, "/boot/config-%s", uts.release); |
---|
| 1664 | + if (len < 0) |
---|
| 1665 | + return -EINVAL; |
---|
| 1666 | + else if (len >= PATH_MAX) |
---|
| 1667 | + return -ENAMETOOLONG; |
---|
| 1668 | + |
---|
| 1669 | + /* gzopen also accepts uncompressed files. */ |
---|
| 1670 | + file = gzopen(buf, "r"); |
---|
| 1671 | + if (!file) |
---|
| 1672 | + file = gzopen("/proc/config.gz", "r"); |
---|
| 1673 | + |
---|
| 1674 | + if (!file) { |
---|
| 1675 | + pr_warn("failed to open system Kconfig\n"); |
---|
| 1676 | + return -ENOENT; |
---|
| 1677 | + } |
---|
| 1678 | + |
---|
| 1679 | + while (gzgets(file, buf, sizeof(buf))) { |
---|
| 1680 | + err = bpf_object__process_kconfig_line(obj, buf, data); |
---|
| 1681 | + if (err) { |
---|
| 1682 | + pr_warn("error parsing system Kconfig line '%s': %d\n", |
---|
| 1683 | + buf, err); |
---|
| 1684 | + goto out; |
---|
| 1685 | + } |
---|
| 1686 | + } |
---|
| 1687 | + |
---|
| 1688 | +out: |
---|
| 1689 | + gzclose(file); |
---|
| 1690 | + return err; |
---|
| 1691 | +} |
---|
| 1692 | + |
---|
| 1693 | +static int bpf_object__read_kconfig_mem(struct bpf_object *obj, |
---|
| 1694 | + const char *config, void *data) |
---|
| 1695 | +{ |
---|
| 1696 | + char buf[PATH_MAX]; |
---|
| 1697 | + int err = 0; |
---|
| 1698 | + FILE *file; |
---|
| 1699 | + |
---|
| 1700 | + file = fmemopen((void *)config, strlen(config), "r"); |
---|
| 1701 | + if (!file) { |
---|
| 1702 | + err = -errno; |
---|
| 1703 | + pr_warn("failed to open in-memory Kconfig: %d\n", err); |
---|
| 1704 | + return err; |
---|
| 1705 | + } |
---|
| 1706 | + |
---|
| 1707 | + while (fgets(buf, sizeof(buf), file)) { |
---|
| 1708 | + err = bpf_object__process_kconfig_line(obj, buf, data); |
---|
| 1709 | + if (err) { |
---|
| 1710 | + pr_warn("error parsing in-memory Kconfig line '%s': %d\n", |
---|
| 1711 | + buf, err); |
---|
| 1712 | + break; |
---|
| 1713 | + } |
---|
| 1714 | + } |
---|
| 1715 | + |
---|
| 1716 | + fclose(file); |
---|
| 1717 | + return err; |
---|
| 1718 | +} |
---|
| 1719 | + |
---|
| 1720 | +static int bpf_object__init_kconfig_map(struct bpf_object *obj) |
---|
| 1721 | +{ |
---|
| 1722 | + struct extern_desc *last_ext = NULL, *ext; |
---|
| 1723 | + size_t map_sz; |
---|
| 1724 | + int i, err; |
---|
| 1725 | + |
---|
| 1726 | + for (i = 0; i < obj->nr_extern; i++) { |
---|
| 1727 | + ext = &obj->externs[i]; |
---|
| 1728 | + if (ext->type == EXT_KCFG) |
---|
| 1729 | + last_ext = ext; |
---|
| 1730 | + } |
---|
| 1731 | + |
---|
| 1732 | + if (!last_ext) |
---|
| 1733 | + return 0; |
---|
| 1734 | + |
---|
| 1735 | + map_sz = last_ext->kcfg.data_off + last_ext->kcfg.sz; |
---|
| 1736 | + err = bpf_object__init_internal_map(obj, LIBBPF_MAP_KCONFIG, |
---|
| 1737 | + obj->efile.symbols_shndx, |
---|
| 1738 | + NULL, map_sz); |
---|
| 1739 | + if (err) |
---|
| 1740 | + return err; |
---|
| 1741 | + |
---|
| 1742 | + obj->kconfig_map_idx = obj->nr_maps - 1; |
---|
| 1743 | + |
---|
| 1744 | + return 0; |
---|
| 1745 | +} |
---|
| 1746 | + |
---|
| 1747 | +static int bpf_object__init_user_maps(struct bpf_object *obj, bool strict) |
---|
| 1748 | +{ |
---|
584 | 1749 | Elf_Data *symbols = obj->efile.symbols; |
---|
| 1750 | + int i, map_def_sz = 0, nr_maps = 0, nr_syms; |
---|
| 1751 | + Elf_Data *data = NULL; |
---|
| 1752 | + Elf_Scn *scn; |
---|
585 | 1753 | |
---|
586 | 1754 | if (obj->efile.maps_shndx < 0) |
---|
587 | | - return -EINVAL; |
---|
| 1755 | + return 0; |
---|
| 1756 | + |
---|
588 | 1757 | if (!symbols) |
---|
589 | 1758 | return -EINVAL; |
---|
590 | 1759 | |
---|
591 | | - scn = elf_getscn(obj->efile.elf, obj->efile.maps_shndx); |
---|
592 | | - if (scn) |
---|
593 | | - data = elf_getdata(scn, NULL); |
---|
| 1760 | + |
---|
| 1761 | + scn = elf_sec_by_idx(obj, obj->efile.maps_shndx); |
---|
| 1762 | + data = elf_sec_data(obj, scn); |
---|
594 | 1763 | if (!scn || !data) { |
---|
595 | | - pr_warning("failed to get Elf_Data from map section %d\n", |
---|
596 | | - obj->efile.maps_shndx); |
---|
| 1764 | + pr_warn("elf: failed to get legacy map definitions for %s\n", |
---|
| 1765 | + obj->path); |
---|
597 | 1766 | return -EINVAL; |
---|
598 | 1767 | } |
---|
599 | 1768 | |
---|
.. | .. |
---|
604 | 1773 | * |
---|
605 | 1774 | * TODO: Detect array of map and report error. |
---|
606 | 1775 | */ |
---|
607 | | - for (i = 0; i < symbols->d_size / sizeof(GElf_Sym); i++) { |
---|
| 1776 | + nr_syms = symbols->d_size / sizeof(GElf_Sym); |
---|
| 1777 | + for (i = 0; i < nr_syms; i++) { |
---|
608 | 1778 | GElf_Sym sym; |
---|
609 | 1779 | |
---|
610 | 1780 | if (!gelf_getsym(symbols, i, &sym)) |
---|
.. | .. |
---|
613 | 1783 | continue; |
---|
614 | 1784 | nr_maps++; |
---|
615 | 1785 | } |
---|
616 | | - |
---|
617 | | - /* Alloc obj->maps and fill nr_maps. */ |
---|
618 | | - pr_debug("maps in %s: %d maps in %zd bytes\n", obj->path, |
---|
619 | | - nr_maps, data->d_size); |
---|
620 | | - |
---|
621 | | - if (!nr_maps) |
---|
622 | | - return 0; |
---|
623 | | - |
---|
624 | 1786 | /* Assume equally sized map definitions */ |
---|
625 | | - map_def_sz = data->d_size / nr_maps; |
---|
626 | | - if (!data->d_size || (data->d_size % nr_maps) != 0) { |
---|
627 | | - pr_warning("unable to determine map definition size " |
---|
628 | | - "section %s, %d maps in %zd bytes\n", |
---|
629 | | - obj->path, nr_maps, data->d_size); |
---|
| 1787 | + pr_debug("elf: found %d legacy map definitions (%zd bytes) in %s\n", |
---|
| 1788 | + nr_maps, data->d_size, obj->path); |
---|
| 1789 | + |
---|
| 1790 | + if (!data->d_size || nr_maps == 0 || (data->d_size % nr_maps) != 0) { |
---|
| 1791 | + pr_warn("elf: unable to determine legacy map definition size in %s\n", |
---|
| 1792 | + obj->path); |
---|
630 | 1793 | return -EINVAL; |
---|
631 | 1794 | } |
---|
| 1795 | + map_def_sz = data->d_size / nr_maps; |
---|
632 | 1796 | |
---|
633 | | - obj->maps = calloc(nr_maps, sizeof(obj->maps[0])); |
---|
634 | | - if (!obj->maps) { |
---|
635 | | - pr_warning("alloc maps for object failed\n"); |
---|
636 | | - return -ENOMEM; |
---|
637 | | - } |
---|
638 | | - obj->nr_maps = nr_maps; |
---|
639 | | - |
---|
640 | | - /* |
---|
641 | | - * fill all fd with -1 so won't close incorrect |
---|
642 | | - * fd (fd=0 is stdin) when failure (zclose won't close |
---|
643 | | - * negative fd)). |
---|
644 | | - */ |
---|
645 | | - for (i = 0; i < nr_maps; i++) |
---|
646 | | - obj->maps[i].fd = -1; |
---|
647 | | - |
---|
648 | | - /* |
---|
649 | | - * Fill obj->maps using data in "maps" section. |
---|
650 | | - */ |
---|
651 | | - for (i = 0, map_idx = 0; i < symbols->d_size / sizeof(GElf_Sym); i++) { |
---|
| 1797 | + /* Fill obj->maps using data in "maps" section. */ |
---|
| 1798 | + for (i = 0; i < nr_syms; i++) { |
---|
652 | 1799 | GElf_Sym sym; |
---|
653 | 1800 | const char *map_name; |
---|
654 | 1801 | struct bpf_map_def *def; |
---|
| 1802 | + struct bpf_map *map; |
---|
655 | 1803 | |
---|
656 | 1804 | if (!gelf_getsym(symbols, i, &sym)) |
---|
657 | 1805 | continue; |
---|
658 | 1806 | if (sym.st_shndx != obj->efile.maps_shndx) |
---|
659 | 1807 | continue; |
---|
660 | 1808 | |
---|
661 | | - map_name = elf_strptr(obj->efile.elf, |
---|
662 | | - obj->efile.strtabidx, |
---|
663 | | - sym.st_name); |
---|
664 | | - obj->maps[map_idx].offset = sym.st_value; |
---|
| 1809 | + map = bpf_object__add_map(obj); |
---|
| 1810 | + if (IS_ERR(map)) |
---|
| 1811 | + return PTR_ERR(map); |
---|
| 1812 | + |
---|
| 1813 | + map_name = elf_sym_str(obj, sym.st_name); |
---|
| 1814 | + if (!map_name) { |
---|
| 1815 | + pr_warn("failed to get map #%d name sym string for obj %s\n", |
---|
| 1816 | + i, obj->path); |
---|
| 1817 | + return -LIBBPF_ERRNO__FORMAT; |
---|
| 1818 | + } |
---|
| 1819 | + |
---|
| 1820 | + map->libbpf_type = LIBBPF_MAP_UNSPEC; |
---|
| 1821 | + map->sec_idx = sym.st_shndx; |
---|
| 1822 | + map->sec_offset = sym.st_value; |
---|
| 1823 | + pr_debug("map '%s' (legacy): at sec_idx %d, offset %zu.\n", |
---|
| 1824 | + map_name, map->sec_idx, map->sec_offset); |
---|
665 | 1825 | if (sym.st_value + map_def_sz > data->d_size) { |
---|
666 | | - pr_warning("corrupted maps section in %s: last map \"%s\" too small\n", |
---|
667 | | - obj->path, map_name); |
---|
| 1826 | + pr_warn("corrupted maps section in %s: last map \"%s\" too small\n", |
---|
| 1827 | + obj->path, map_name); |
---|
668 | 1828 | return -EINVAL; |
---|
669 | 1829 | } |
---|
670 | 1830 | |
---|
671 | | - obj->maps[map_idx].name = strdup(map_name); |
---|
672 | | - if (!obj->maps[map_idx].name) { |
---|
673 | | - pr_warning("failed to alloc map name\n"); |
---|
| 1831 | + map->name = strdup(map_name); |
---|
| 1832 | + if (!map->name) { |
---|
| 1833 | + pr_warn("failed to alloc map name\n"); |
---|
674 | 1834 | return -ENOMEM; |
---|
675 | 1835 | } |
---|
676 | | - pr_debug("map %d is \"%s\"\n", map_idx, |
---|
677 | | - obj->maps[map_idx].name); |
---|
| 1836 | + pr_debug("map %d is \"%s\"\n", i, map->name); |
---|
678 | 1837 | def = (struct bpf_map_def *)(data->d_buf + sym.st_value); |
---|
679 | 1838 | /* |
---|
680 | 1839 | * If the definition of the map in the object file fits in |
---|
.. | .. |
---|
683 | 1842 | * calloc above. |
---|
684 | 1843 | */ |
---|
685 | 1844 | if (map_def_sz <= sizeof(struct bpf_map_def)) { |
---|
686 | | - memcpy(&obj->maps[map_idx].def, def, map_def_sz); |
---|
| 1845 | + memcpy(&map->def, def, map_def_sz); |
---|
687 | 1846 | } else { |
---|
688 | 1847 | /* |
---|
689 | 1848 | * Here the map structure being read is bigger than what |
---|
.. | .. |
---|
692 | 1851 | * incompatible. |
---|
693 | 1852 | */ |
---|
694 | 1853 | char *b; |
---|
| 1854 | + |
---|
695 | 1855 | for (b = ((char *)def) + sizeof(struct bpf_map_def); |
---|
696 | 1856 | b < ((char *)def) + map_def_sz; b++) { |
---|
697 | 1857 | if (*b != 0) { |
---|
698 | | - pr_warning("maps section in %s: \"%s\" " |
---|
699 | | - "has unrecognized, non-zero " |
---|
700 | | - "options\n", |
---|
701 | | - obj->path, map_name); |
---|
702 | | - return -EINVAL; |
---|
| 1858 | + pr_warn("maps section in %s: \"%s\" has unrecognized, non-zero options\n", |
---|
| 1859 | + obj->path, map_name); |
---|
| 1860 | + if (strict) |
---|
| 1861 | + return -EINVAL; |
---|
703 | 1862 | } |
---|
704 | 1863 | } |
---|
705 | | - memcpy(&obj->maps[map_idx].def, def, |
---|
706 | | - sizeof(struct bpf_map_def)); |
---|
| 1864 | + memcpy(&map->def, def, sizeof(struct bpf_map_def)); |
---|
707 | 1865 | } |
---|
708 | | - map_idx++; |
---|
| 1866 | + } |
---|
| 1867 | + return 0; |
---|
| 1868 | +} |
---|
| 1869 | + |
---|
| 1870 | +static const struct btf_type * |
---|
| 1871 | +skip_mods_and_typedefs(const struct btf *btf, __u32 id, __u32 *res_id) |
---|
| 1872 | +{ |
---|
| 1873 | + const struct btf_type *t = btf__type_by_id(btf, id); |
---|
| 1874 | + |
---|
| 1875 | + if (res_id) |
---|
| 1876 | + *res_id = id; |
---|
| 1877 | + |
---|
| 1878 | + while (btf_is_mod(t) || btf_is_typedef(t)) { |
---|
| 1879 | + if (res_id) |
---|
| 1880 | + *res_id = t->type; |
---|
| 1881 | + t = btf__type_by_id(btf, t->type); |
---|
709 | 1882 | } |
---|
710 | 1883 | |
---|
711 | | - qsort(obj->maps, obj->nr_maps, sizeof(obj->maps[0]), compare_bpf_map); |
---|
| 1884 | + return t; |
---|
| 1885 | +} |
---|
| 1886 | + |
---|
| 1887 | +static const struct btf_type * |
---|
| 1888 | +resolve_func_ptr(const struct btf *btf, __u32 id, __u32 *res_id) |
---|
| 1889 | +{ |
---|
| 1890 | + const struct btf_type *t; |
---|
| 1891 | + |
---|
| 1892 | + t = skip_mods_and_typedefs(btf, id, NULL); |
---|
| 1893 | + if (!btf_is_ptr(t)) |
---|
| 1894 | + return NULL; |
---|
| 1895 | + |
---|
| 1896 | + t = skip_mods_and_typedefs(btf, t->type, res_id); |
---|
| 1897 | + |
---|
| 1898 | + return btf_is_func_proto(t) ? t : NULL; |
---|
| 1899 | +} |
---|
| 1900 | + |
---|
| 1901 | +static const char *btf_kind_str(const struct btf_type *t) |
---|
| 1902 | +{ |
---|
| 1903 | + switch (btf_kind(t)) { |
---|
| 1904 | + case BTF_KIND_UNKN: return "void"; |
---|
| 1905 | + case BTF_KIND_INT: return "int"; |
---|
| 1906 | + case BTF_KIND_PTR: return "ptr"; |
---|
| 1907 | + case BTF_KIND_ARRAY: return "array"; |
---|
| 1908 | + case BTF_KIND_STRUCT: return "struct"; |
---|
| 1909 | + case BTF_KIND_UNION: return "union"; |
---|
| 1910 | + case BTF_KIND_ENUM: return "enum"; |
---|
| 1911 | + case BTF_KIND_FWD: return "fwd"; |
---|
| 1912 | + case BTF_KIND_TYPEDEF: return "typedef"; |
---|
| 1913 | + case BTF_KIND_VOLATILE: return "volatile"; |
---|
| 1914 | + case BTF_KIND_CONST: return "const"; |
---|
| 1915 | + case BTF_KIND_RESTRICT: return "restrict"; |
---|
| 1916 | + case BTF_KIND_FUNC: return "func"; |
---|
| 1917 | + case BTF_KIND_FUNC_PROTO: return "func_proto"; |
---|
| 1918 | + case BTF_KIND_VAR: return "var"; |
---|
| 1919 | + case BTF_KIND_DATASEC: return "datasec"; |
---|
| 1920 | + default: return "unknown"; |
---|
| 1921 | + } |
---|
| 1922 | +} |
---|
| 1923 | + |
---|
| 1924 | +/* |
---|
| 1925 | + * Fetch integer attribute of BTF map definition. Such attributes are |
---|
| 1926 | + * represented using a pointer to an array, in which dimensionality of array |
---|
| 1927 | + * encodes specified integer value. E.g., int (*type)[BPF_MAP_TYPE_ARRAY]; |
---|
| 1928 | + * encodes `type => BPF_MAP_TYPE_ARRAY` key/value pair completely using BTF |
---|
| 1929 | + * type definition, while using only sizeof(void *) space in ELF data section. |
---|
| 1930 | + */ |
---|
| 1931 | +static bool get_map_field_int(const char *map_name, const struct btf *btf, |
---|
| 1932 | + const struct btf_member *m, __u32 *res) |
---|
| 1933 | +{ |
---|
| 1934 | + const struct btf_type *t = skip_mods_and_typedefs(btf, m->type, NULL); |
---|
| 1935 | + const char *name = btf__name_by_offset(btf, m->name_off); |
---|
| 1936 | + const struct btf_array *arr_info; |
---|
| 1937 | + const struct btf_type *arr_t; |
---|
| 1938 | + |
---|
| 1939 | + if (!btf_is_ptr(t)) { |
---|
| 1940 | + pr_warn("map '%s': attr '%s': expected PTR, got %s.\n", |
---|
| 1941 | + map_name, name, btf_kind_str(t)); |
---|
| 1942 | + return false; |
---|
| 1943 | + } |
---|
| 1944 | + |
---|
| 1945 | + arr_t = btf__type_by_id(btf, t->type); |
---|
| 1946 | + if (!arr_t) { |
---|
| 1947 | + pr_warn("map '%s': attr '%s': type [%u] not found.\n", |
---|
| 1948 | + map_name, name, t->type); |
---|
| 1949 | + return false; |
---|
| 1950 | + } |
---|
| 1951 | + if (!btf_is_array(arr_t)) { |
---|
| 1952 | + pr_warn("map '%s': attr '%s': expected ARRAY, got %s.\n", |
---|
| 1953 | + map_name, name, btf_kind_str(arr_t)); |
---|
| 1954 | + return false; |
---|
| 1955 | + } |
---|
| 1956 | + arr_info = btf_array(arr_t); |
---|
| 1957 | + *res = arr_info->nelems; |
---|
| 1958 | + return true; |
---|
| 1959 | +} |
---|
| 1960 | + |
---|
| 1961 | +static int build_map_pin_path(struct bpf_map *map, const char *path) |
---|
| 1962 | +{ |
---|
| 1963 | + char buf[PATH_MAX]; |
---|
| 1964 | + int len; |
---|
| 1965 | + |
---|
| 1966 | + if (!path) |
---|
| 1967 | + path = "/sys/fs/bpf"; |
---|
| 1968 | + |
---|
| 1969 | + len = snprintf(buf, PATH_MAX, "%s/%s", path, bpf_map__name(map)); |
---|
| 1970 | + if (len < 0) |
---|
| 1971 | + return -EINVAL; |
---|
| 1972 | + else if (len >= PATH_MAX) |
---|
| 1973 | + return -ENAMETOOLONG; |
---|
| 1974 | + |
---|
| 1975 | + return bpf_map__set_pin_path(map, buf); |
---|
| 1976 | +} |
---|
| 1977 | + |
---|
| 1978 | + |
---|
| 1979 | +static int parse_btf_map_def(struct bpf_object *obj, |
---|
| 1980 | + struct bpf_map *map, |
---|
| 1981 | + const struct btf_type *def, |
---|
| 1982 | + bool strict, bool is_inner, |
---|
| 1983 | + const char *pin_root_path) |
---|
| 1984 | +{ |
---|
| 1985 | + const struct btf_type *t; |
---|
| 1986 | + const struct btf_member *m; |
---|
| 1987 | + int vlen, i; |
---|
| 1988 | + |
---|
| 1989 | + vlen = btf_vlen(def); |
---|
| 1990 | + m = btf_members(def); |
---|
| 1991 | + for (i = 0; i < vlen; i++, m++) { |
---|
| 1992 | + const char *name = btf__name_by_offset(obj->btf, m->name_off); |
---|
| 1993 | + |
---|
| 1994 | + if (!name) { |
---|
| 1995 | + pr_warn("map '%s': invalid field #%d.\n", map->name, i); |
---|
| 1996 | + return -EINVAL; |
---|
| 1997 | + } |
---|
| 1998 | + if (strcmp(name, "type") == 0) { |
---|
| 1999 | + if (!get_map_field_int(map->name, obj->btf, m, |
---|
| 2000 | + &map->def.type)) |
---|
| 2001 | + return -EINVAL; |
---|
| 2002 | + pr_debug("map '%s': found type = %u.\n", |
---|
| 2003 | + map->name, map->def.type); |
---|
| 2004 | + } else if (strcmp(name, "max_entries") == 0) { |
---|
| 2005 | + if (!get_map_field_int(map->name, obj->btf, m, |
---|
| 2006 | + &map->def.max_entries)) |
---|
| 2007 | + return -EINVAL; |
---|
| 2008 | + pr_debug("map '%s': found max_entries = %u.\n", |
---|
| 2009 | + map->name, map->def.max_entries); |
---|
| 2010 | + } else if (strcmp(name, "map_flags") == 0) { |
---|
| 2011 | + if (!get_map_field_int(map->name, obj->btf, m, |
---|
| 2012 | + &map->def.map_flags)) |
---|
| 2013 | + return -EINVAL; |
---|
| 2014 | + pr_debug("map '%s': found map_flags = %u.\n", |
---|
| 2015 | + map->name, map->def.map_flags); |
---|
| 2016 | + } else if (strcmp(name, "numa_node") == 0) { |
---|
| 2017 | + if (!get_map_field_int(map->name, obj->btf, m, &map->numa_node)) |
---|
| 2018 | + return -EINVAL; |
---|
| 2019 | + pr_debug("map '%s': found numa_node = %u.\n", map->name, map->numa_node); |
---|
| 2020 | + } else if (strcmp(name, "key_size") == 0) { |
---|
| 2021 | + __u32 sz; |
---|
| 2022 | + |
---|
| 2023 | + if (!get_map_field_int(map->name, obj->btf, m, &sz)) |
---|
| 2024 | + return -EINVAL; |
---|
| 2025 | + pr_debug("map '%s': found key_size = %u.\n", |
---|
| 2026 | + map->name, sz); |
---|
| 2027 | + if (map->def.key_size && map->def.key_size != sz) { |
---|
| 2028 | + pr_warn("map '%s': conflicting key size %u != %u.\n", |
---|
| 2029 | + map->name, map->def.key_size, sz); |
---|
| 2030 | + return -EINVAL; |
---|
| 2031 | + } |
---|
| 2032 | + map->def.key_size = sz; |
---|
| 2033 | + } else if (strcmp(name, "key") == 0) { |
---|
| 2034 | + __s64 sz; |
---|
| 2035 | + |
---|
| 2036 | + t = btf__type_by_id(obj->btf, m->type); |
---|
| 2037 | + if (!t) { |
---|
| 2038 | + pr_warn("map '%s': key type [%d] not found.\n", |
---|
| 2039 | + map->name, m->type); |
---|
| 2040 | + return -EINVAL; |
---|
| 2041 | + } |
---|
| 2042 | + if (!btf_is_ptr(t)) { |
---|
| 2043 | + pr_warn("map '%s': key spec is not PTR: %s.\n", |
---|
| 2044 | + map->name, btf_kind_str(t)); |
---|
| 2045 | + return -EINVAL; |
---|
| 2046 | + } |
---|
| 2047 | + sz = btf__resolve_size(obj->btf, t->type); |
---|
| 2048 | + if (sz < 0) { |
---|
| 2049 | + pr_warn("map '%s': can't determine key size for type [%u]: %zd.\n", |
---|
| 2050 | + map->name, t->type, (ssize_t)sz); |
---|
| 2051 | + return sz; |
---|
| 2052 | + } |
---|
| 2053 | + pr_debug("map '%s': found key [%u], sz = %zd.\n", |
---|
| 2054 | + map->name, t->type, (ssize_t)sz); |
---|
| 2055 | + if (map->def.key_size && map->def.key_size != sz) { |
---|
| 2056 | + pr_warn("map '%s': conflicting key size %u != %zd.\n", |
---|
| 2057 | + map->name, map->def.key_size, (ssize_t)sz); |
---|
| 2058 | + return -EINVAL; |
---|
| 2059 | + } |
---|
| 2060 | + map->def.key_size = sz; |
---|
| 2061 | + map->btf_key_type_id = t->type; |
---|
| 2062 | + } else if (strcmp(name, "value_size") == 0) { |
---|
| 2063 | + __u32 sz; |
---|
| 2064 | + |
---|
| 2065 | + if (!get_map_field_int(map->name, obj->btf, m, &sz)) |
---|
| 2066 | + return -EINVAL; |
---|
| 2067 | + pr_debug("map '%s': found value_size = %u.\n", |
---|
| 2068 | + map->name, sz); |
---|
| 2069 | + if (map->def.value_size && map->def.value_size != sz) { |
---|
| 2070 | + pr_warn("map '%s': conflicting value size %u != %u.\n", |
---|
| 2071 | + map->name, map->def.value_size, sz); |
---|
| 2072 | + return -EINVAL; |
---|
| 2073 | + } |
---|
| 2074 | + map->def.value_size = sz; |
---|
| 2075 | + } else if (strcmp(name, "value") == 0) { |
---|
| 2076 | + __s64 sz; |
---|
| 2077 | + |
---|
| 2078 | + t = btf__type_by_id(obj->btf, m->type); |
---|
| 2079 | + if (!t) { |
---|
| 2080 | + pr_warn("map '%s': value type [%d] not found.\n", |
---|
| 2081 | + map->name, m->type); |
---|
| 2082 | + return -EINVAL; |
---|
| 2083 | + } |
---|
| 2084 | + if (!btf_is_ptr(t)) { |
---|
| 2085 | + pr_warn("map '%s': value spec is not PTR: %s.\n", |
---|
| 2086 | + map->name, btf_kind_str(t)); |
---|
| 2087 | + return -EINVAL; |
---|
| 2088 | + } |
---|
| 2089 | + sz = btf__resolve_size(obj->btf, t->type); |
---|
| 2090 | + if (sz < 0) { |
---|
| 2091 | + pr_warn("map '%s': can't determine value size for type [%u]: %zd.\n", |
---|
| 2092 | + map->name, t->type, (ssize_t)sz); |
---|
| 2093 | + return sz; |
---|
| 2094 | + } |
---|
| 2095 | + pr_debug("map '%s': found value [%u], sz = %zd.\n", |
---|
| 2096 | + map->name, t->type, (ssize_t)sz); |
---|
| 2097 | + if (map->def.value_size && map->def.value_size != sz) { |
---|
| 2098 | + pr_warn("map '%s': conflicting value size %u != %zd.\n", |
---|
| 2099 | + map->name, map->def.value_size, (ssize_t)sz); |
---|
| 2100 | + return -EINVAL; |
---|
| 2101 | + } |
---|
| 2102 | + map->def.value_size = sz; |
---|
| 2103 | + map->btf_value_type_id = t->type; |
---|
| 2104 | + } |
---|
| 2105 | + else if (strcmp(name, "values") == 0) { |
---|
| 2106 | + int err; |
---|
| 2107 | + |
---|
| 2108 | + if (is_inner) { |
---|
| 2109 | + pr_warn("map '%s': multi-level inner maps not supported.\n", |
---|
| 2110 | + map->name); |
---|
| 2111 | + return -ENOTSUP; |
---|
| 2112 | + } |
---|
| 2113 | + if (i != vlen - 1) { |
---|
| 2114 | + pr_warn("map '%s': '%s' member should be last.\n", |
---|
| 2115 | + map->name, name); |
---|
| 2116 | + return -EINVAL; |
---|
| 2117 | + } |
---|
| 2118 | + if (!bpf_map_type__is_map_in_map(map->def.type)) { |
---|
| 2119 | + pr_warn("map '%s': should be map-in-map.\n", |
---|
| 2120 | + map->name); |
---|
| 2121 | + return -ENOTSUP; |
---|
| 2122 | + } |
---|
| 2123 | + if (map->def.value_size && map->def.value_size != 4) { |
---|
| 2124 | + pr_warn("map '%s': conflicting value size %u != 4.\n", |
---|
| 2125 | + map->name, map->def.value_size); |
---|
| 2126 | + return -EINVAL; |
---|
| 2127 | + } |
---|
| 2128 | + map->def.value_size = 4; |
---|
| 2129 | + t = btf__type_by_id(obj->btf, m->type); |
---|
| 2130 | + if (!t) { |
---|
| 2131 | + pr_warn("map '%s': map-in-map inner type [%d] not found.\n", |
---|
| 2132 | + map->name, m->type); |
---|
| 2133 | + return -EINVAL; |
---|
| 2134 | + } |
---|
| 2135 | + if (!btf_is_array(t) || btf_array(t)->nelems) { |
---|
| 2136 | + pr_warn("map '%s': map-in-map inner spec is not a zero-sized array.\n", |
---|
| 2137 | + map->name); |
---|
| 2138 | + return -EINVAL; |
---|
| 2139 | + } |
---|
| 2140 | + t = skip_mods_and_typedefs(obj->btf, btf_array(t)->type, |
---|
| 2141 | + NULL); |
---|
| 2142 | + if (!btf_is_ptr(t)) { |
---|
| 2143 | + pr_warn("map '%s': map-in-map inner def is of unexpected kind %s.\n", |
---|
| 2144 | + map->name, btf_kind_str(t)); |
---|
| 2145 | + return -EINVAL; |
---|
| 2146 | + } |
---|
| 2147 | + t = skip_mods_and_typedefs(obj->btf, t->type, NULL); |
---|
| 2148 | + if (!btf_is_struct(t)) { |
---|
| 2149 | + pr_warn("map '%s': map-in-map inner def is of unexpected kind %s.\n", |
---|
| 2150 | + map->name, btf_kind_str(t)); |
---|
| 2151 | + return -EINVAL; |
---|
| 2152 | + } |
---|
| 2153 | + |
---|
| 2154 | + map->inner_map = calloc(1, sizeof(*map->inner_map)); |
---|
| 2155 | + if (!map->inner_map) |
---|
| 2156 | + return -ENOMEM; |
---|
| 2157 | + map->inner_map->sec_idx = obj->efile.btf_maps_shndx; |
---|
| 2158 | + map->inner_map->name = malloc(strlen(map->name) + |
---|
| 2159 | + sizeof(".inner") + 1); |
---|
| 2160 | + if (!map->inner_map->name) |
---|
| 2161 | + return -ENOMEM; |
---|
| 2162 | + sprintf(map->inner_map->name, "%s.inner", map->name); |
---|
| 2163 | + |
---|
| 2164 | + err = parse_btf_map_def(obj, map->inner_map, t, strict, |
---|
| 2165 | + true /* is_inner */, NULL); |
---|
| 2166 | + if (err) |
---|
| 2167 | + return err; |
---|
| 2168 | + } else if (strcmp(name, "pinning") == 0) { |
---|
| 2169 | + __u32 val; |
---|
| 2170 | + int err; |
---|
| 2171 | + |
---|
| 2172 | + if (is_inner) { |
---|
| 2173 | + pr_debug("map '%s': inner def can't be pinned.\n", |
---|
| 2174 | + map->name); |
---|
| 2175 | + return -EINVAL; |
---|
| 2176 | + } |
---|
| 2177 | + if (!get_map_field_int(map->name, obj->btf, m, &val)) |
---|
| 2178 | + return -EINVAL; |
---|
| 2179 | + pr_debug("map '%s': found pinning = %u.\n", |
---|
| 2180 | + map->name, val); |
---|
| 2181 | + |
---|
| 2182 | + if (val != LIBBPF_PIN_NONE && |
---|
| 2183 | + val != LIBBPF_PIN_BY_NAME) { |
---|
| 2184 | + pr_warn("map '%s': invalid pinning value %u.\n", |
---|
| 2185 | + map->name, val); |
---|
| 2186 | + return -EINVAL; |
---|
| 2187 | + } |
---|
| 2188 | + if (val == LIBBPF_PIN_BY_NAME) { |
---|
| 2189 | + err = build_map_pin_path(map, pin_root_path); |
---|
| 2190 | + if (err) { |
---|
| 2191 | + pr_warn("map '%s': couldn't build pin path.\n", |
---|
| 2192 | + map->name); |
---|
| 2193 | + return err; |
---|
| 2194 | + } |
---|
| 2195 | + } |
---|
| 2196 | + } else { |
---|
| 2197 | + if (strict) { |
---|
| 2198 | + pr_warn("map '%s': unknown field '%s'.\n", |
---|
| 2199 | + map->name, name); |
---|
| 2200 | + return -ENOTSUP; |
---|
| 2201 | + } |
---|
| 2202 | + pr_debug("map '%s': ignoring unknown field '%s'.\n", |
---|
| 2203 | + map->name, name); |
---|
| 2204 | + } |
---|
| 2205 | + } |
---|
| 2206 | + |
---|
| 2207 | + if (map->def.type == BPF_MAP_TYPE_UNSPEC) { |
---|
| 2208 | + pr_warn("map '%s': map type isn't specified.\n", map->name); |
---|
| 2209 | + return -EINVAL; |
---|
| 2210 | + } |
---|
| 2211 | + |
---|
| 2212 | + return 0; |
---|
| 2213 | +} |
---|
| 2214 | + |
---|
| 2215 | +static int bpf_object__init_user_btf_map(struct bpf_object *obj, |
---|
| 2216 | + const struct btf_type *sec, |
---|
| 2217 | + int var_idx, int sec_idx, |
---|
| 2218 | + const Elf_Data *data, bool strict, |
---|
| 2219 | + const char *pin_root_path) |
---|
| 2220 | +{ |
---|
| 2221 | + const struct btf_type *var, *def; |
---|
| 2222 | + const struct btf_var_secinfo *vi; |
---|
| 2223 | + const struct btf_var *var_extra; |
---|
| 2224 | + const char *map_name; |
---|
| 2225 | + struct bpf_map *map; |
---|
| 2226 | + |
---|
| 2227 | + vi = btf_var_secinfos(sec) + var_idx; |
---|
| 2228 | + var = btf__type_by_id(obj->btf, vi->type); |
---|
| 2229 | + var_extra = btf_var(var); |
---|
| 2230 | + map_name = btf__name_by_offset(obj->btf, var->name_off); |
---|
| 2231 | + |
---|
| 2232 | + if (map_name == NULL || map_name[0] == '\0') { |
---|
| 2233 | + pr_warn("map #%d: empty name.\n", var_idx); |
---|
| 2234 | + return -EINVAL; |
---|
| 2235 | + } |
---|
| 2236 | + if ((__u64)vi->offset + vi->size > data->d_size) { |
---|
| 2237 | + pr_warn("map '%s' BTF data is corrupted.\n", map_name); |
---|
| 2238 | + return -EINVAL; |
---|
| 2239 | + } |
---|
| 2240 | + if (!btf_is_var(var)) { |
---|
| 2241 | + pr_warn("map '%s': unexpected var kind %s.\n", |
---|
| 2242 | + map_name, btf_kind_str(var)); |
---|
| 2243 | + return -EINVAL; |
---|
| 2244 | + } |
---|
| 2245 | + if (var_extra->linkage != BTF_VAR_GLOBAL_ALLOCATED && |
---|
| 2246 | + var_extra->linkage != BTF_VAR_STATIC) { |
---|
| 2247 | + pr_warn("map '%s': unsupported var linkage %u.\n", |
---|
| 2248 | + map_name, var_extra->linkage); |
---|
| 2249 | + return -EOPNOTSUPP; |
---|
| 2250 | + } |
---|
| 2251 | + |
---|
| 2252 | + def = skip_mods_and_typedefs(obj->btf, var->type, NULL); |
---|
| 2253 | + if (!btf_is_struct(def)) { |
---|
| 2254 | + pr_warn("map '%s': unexpected def kind %s.\n", |
---|
| 2255 | + map_name, btf_kind_str(var)); |
---|
| 2256 | + return -EINVAL; |
---|
| 2257 | + } |
---|
| 2258 | + if (def->size > vi->size) { |
---|
| 2259 | + pr_warn("map '%s': invalid def size.\n", map_name); |
---|
| 2260 | + return -EINVAL; |
---|
| 2261 | + } |
---|
| 2262 | + |
---|
| 2263 | + map = bpf_object__add_map(obj); |
---|
| 2264 | + if (IS_ERR(map)) |
---|
| 2265 | + return PTR_ERR(map); |
---|
| 2266 | + map->name = strdup(map_name); |
---|
| 2267 | + if (!map->name) { |
---|
| 2268 | + pr_warn("map '%s': failed to alloc map name.\n", map_name); |
---|
| 2269 | + return -ENOMEM; |
---|
| 2270 | + } |
---|
| 2271 | + map->libbpf_type = LIBBPF_MAP_UNSPEC; |
---|
| 2272 | + map->def.type = BPF_MAP_TYPE_UNSPEC; |
---|
| 2273 | + map->sec_idx = sec_idx; |
---|
| 2274 | + map->sec_offset = vi->offset; |
---|
| 2275 | + map->btf_var_idx = var_idx; |
---|
| 2276 | + pr_debug("map '%s': at sec_idx %d, offset %zu.\n", |
---|
| 2277 | + map_name, map->sec_idx, map->sec_offset); |
---|
| 2278 | + |
---|
| 2279 | + return parse_btf_map_def(obj, map, def, strict, false, pin_root_path); |
---|
| 2280 | +} |
---|
| 2281 | + |
---|
| 2282 | +static int bpf_object__init_user_btf_maps(struct bpf_object *obj, bool strict, |
---|
| 2283 | + const char *pin_root_path) |
---|
| 2284 | +{ |
---|
| 2285 | + const struct btf_type *sec = NULL; |
---|
| 2286 | + int nr_types, i, vlen, err; |
---|
| 2287 | + const struct btf_type *t; |
---|
| 2288 | + const char *name; |
---|
| 2289 | + Elf_Data *data; |
---|
| 2290 | + Elf_Scn *scn; |
---|
| 2291 | + |
---|
| 2292 | + if (obj->efile.btf_maps_shndx < 0) |
---|
| 2293 | + return 0; |
---|
| 2294 | + |
---|
| 2295 | + scn = elf_sec_by_idx(obj, obj->efile.btf_maps_shndx); |
---|
| 2296 | + data = elf_sec_data(obj, scn); |
---|
| 2297 | + if (!scn || !data) { |
---|
| 2298 | + pr_warn("elf: failed to get %s map definitions for %s\n", |
---|
| 2299 | + MAPS_ELF_SEC, obj->path); |
---|
| 2300 | + return -EINVAL; |
---|
| 2301 | + } |
---|
| 2302 | + |
---|
| 2303 | + nr_types = btf__get_nr_types(obj->btf); |
---|
| 2304 | + for (i = 1; i <= nr_types; i++) { |
---|
| 2305 | + t = btf__type_by_id(obj->btf, i); |
---|
| 2306 | + if (!btf_is_datasec(t)) |
---|
| 2307 | + continue; |
---|
| 2308 | + name = btf__name_by_offset(obj->btf, t->name_off); |
---|
| 2309 | + if (strcmp(name, MAPS_ELF_SEC) == 0) { |
---|
| 2310 | + sec = t; |
---|
| 2311 | + obj->efile.btf_maps_sec_btf_id = i; |
---|
| 2312 | + break; |
---|
| 2313 | + } |
---|
| 2314 | + } |
---|
| 2315 | + |
---|
| 2316 | + if (!sec) { |
---|
| 2317 | + pr_warn("DATASEC '%s' not found.\n", MAPS_ELF_SEC); |
---|
| 2318 | + return -ENOENT; |
---|
| 2319 | + } |
---|
| 2320 | + |
---|
| 2321 | + vlen = btf_vlen(sec); |
---|
| 2322 | + for (i = 0; i < vlen; i++) { |
---|
| 2323 | + err = bpf_object__init_user_btf_map(obj, sec, i, |
---|
| 2324 | + obj->efile.btf_maps_shndx, |
---|
| 2325 | + data, strict, |
---|
| 2326 | + pin_root_path); |
---|
| 2327 | + if (err) |
---|
| 2328 | + return err; |
---|
| 2329 | + } |
---|
| 2330 | + |
---|
| 2331 | + return 0; |
---|
| 2332 | +} |
---|
| 2333 | + |
---|
| 2334 | +static int bpf_object__init_maps(struct bpf_object *obj, |
---|
| 2335 | + const struct bpf_object_open_opts *opts) |
---|
| 2336 | +{ |
---|
| 2337 | + const char *pin_root_path; |
---|
| 2338 | + bool strict; |
---|
| 2339 | + int err; |
---|
| 2340 | + |
---|
| 2341 | + strict = !OPTS_GET(opts, relaxed_maps, false); |
---|
| 2342 | + pin_root_path = OPTS_GET(opts, pin_root_path, NULL); |
---|
| 2343 | + |
---|
| 2344 | + err = bpf_object__init_user_maps(obj, strict); |
---|
| 2345 | + err = err ?: bpf_object__init_user_btf_maps(obj, strict, pin_root_path); |
---|
| 2346 | + err = err ?: bpf_object__init_global_data_maps(obj); |
---|
| 2347 | + err = err ?: bpf_object__init_kconfig_map(obj); |
---|
| 2348 | + err = err ?: bpf_object__init_struct_ops_maps(obj); |
---|
| 2349 | + if (err) |
---|
| 2350 | + return err; |
---|
| 2351 | + |
---|
712 | 2352 | return 0; |
---|
713 | 2353 | } |
---|
714 | 2354 | |
---|
715 | 2355 | static bool section_have_execinstr(struct bpf_object *obj, int idx) |
---|
716 | 2356 | { |
---|
717 | | - Elf_Scn *scn; |
---|
718 | 2357 | GElf_Shdr sh; |
---|
719 | 2358 | |
---|
720 | | - scn = elf_getscn(obj->efile.elf, idx); |
---|
721 | | - if (!scn) |
---|
| 2359 | + if (elf_sec_hdr(obj, elf_sec_by_idx(obj, idx), &sh)) |
---|
722 | 2360 | return false; |
---|
723 | 2361 | |
---|
724 | | - if (gelf_getshdr(scn, &sh) != &sh) |
---|
725 | | - return false; |
---|
| 2362 | + return sh.sh_flags & SHF_EXECINSTR; |
---|
| 2363 | +} |
---|
726 | 2364 | |
---|
727 | | - if (sh.sh_flags & SHF_EXECINSTR) |
---|
| 2365 | +static bool btf_needs_sanitization(struct bpf_object *obj) |
---|
| 2366 | +{ |
---|
| 2367 | + bool has_func_global = kernel_supports(FEAT_BTF_GLOBAL_FUNC); |
---|
| 2368 | + bool has_datasec = kernel_supports(FEAT_BTF_DATASEC); |
---|
| 2369 | + bool has_func = kernel_supports(FEAT_BTF_FUNC); |
---|
| 2370 | + |
---|
| 2371 | + return !has_func || !has_datasec || !has_func_global; |
---|
| 2372 | +} |
---|
| 2373 | + |
---|
| 2374 | +static void bpf_object__sanitize_btf(struct bpf_object *obj, struct btf *btf) |
---|
| 2375 | +{ |
---|
| 2376 | + bool has_func_global = kernel_supports(FEAT_BTF_GLOBAL_FUNC); |
---|
| 2377 | + bool has_datasec = kernel_supports(FEAT_BTF_DATASEC); |
---|
| 2378 | + bool has_func = kernel_supports(FEAT_BTF_FUNC); |
---|
| 2379 | + struct btf_type *t; |
---|
| 2380 | + int i, j, vlen; |
---|
| 2381 | + |
---|
| 2382 | + for (i = 1; i <= btf__get_nr_types(btf); i++) { |
---|
| 2383 | + t = (struct btf_type *)btf__type_by_id(btf, i); |
---|
| 2384 | + |
---|
| 2385 | + if (!has_datasec && btf_is_var(t)) { |
---|
| 2386 | + /* replace VAR with INT */ |
---|
| 2387 | + t->info = BTF_INFO_ENC(BTF_KIND_INT, 0, 0); |
---|
| 2388 | + /* |
---|
| 2389 | + * using size = 1 is the safest choice, 4 will be too |
---|
| 2390 | + * big and cause kernel BTF validation failure if |
---|
| 2391 | + * original variable took less than 4 bytes |
---|
| 2392 | + */ |
---|
| 2393 | + t->size = 1; |
---|
| 2394 | + *(int *)(t + 1) = BTF_INT_ENC(0, 0, 8); |
---|
| 2395 | + } else if (!has_datasec && btf_is_datasec(t)) { |
---|
| 2396 | + /* replace DATASEC with STRUCT */ |
---|
| 2397 | + const struct btf_var_secinfo *v = btf_var_secinfos(t); |
---|
| 2398 | + struct btf_member *m = btf_members(t); |
---|
| 2399 | + struct btf_type *vt; |
---|
| 2400 | + char *name; |
---|
| 2401 | + |
---|
| 2402 | + name = (char *)btf__name_by_offset(btf, t->name_off); |
---|
| 2403 | + while (*name) { |
---|
| 2404 | + if (*name == '.') |
---|
| 2405 | + *name = '_'; |
---|
| 2406 | + name++; |
---|
| 2407 | + } |
---|
| 2408 | + |
---|
| 2409 | + vlen = btf_vlen(t); |
---|
| 2410 | + t->info = BTF_INFO_ENC(BTF_KIND_STRUCT, 0, vlen); |
---|
| 2411 | + for (j = 0; j < vlen; j++, v++, m++) { |
---|
| 2412 | + /* order of field assignments is important */ |
---|
| 2413 | + m->offset = v->offset * 8; |
---|
| 2414 | + m->type = v->type; |
---|
| 2415 | + /* preserve variable name as member name */ |
---|
| 2416 | + vt = (void *)btf__type_by_id(btf, v->type); |
---|
| 2417 | + m->name_off = vt->name_off; |
---|
| 2418 | + } |
---|
| 2419 | + } else if (!has_func && btf_is_func_proto(t)) { |
---|
| 2420 | + /* replace FUNC_PROTO with ENUM */ |
---|
| 2421 | + vlen = btf_vlen(t); |
---|
| 2422 | + t->info = BTF_INFO_ENC(BTF_KIND_ENUM, 0, vlen); |
---|
| 2423 | + t->size = sizeof(__u32); /* kernel enforced */ |
---|
| 2424 | + } else if (!has_func && btf_is_func(t)) { |
---|
| 2425 | + /* replace FUNC with TYPEDEF */ |
---|
| 2426 | + t->info = BTF_INFO_ENC(BTF_KIND_TYPEDEF, 0, 0); |
---|
| 2427 | + } else if (!has_func_global && btf_is_func(t)) { |
---|
| 2428 | + /* replace BTF_FUNC_GLOBAL with BTF_FUNC_STATIC */ |
---|
| 2429 | + t->info = BTF_INFO_ENC(BTF_KIND_FUNC, 0, 0); |
---|
| 2430 | + } |
---|
| 2431 | + } |
---|
| 2432 | +} |
---|
| 2433 | + |
---|
| 2434 | +static bool libbpf_needs_btf(const struct bpf_object *obj) |
---|
| 2435 | +{ |
---|
| 2436 | + return obj->efile.btf_maps_shndx >= 0 || |
---|
| 2437 | + obj->efile.st_ops_shndx >= 0 || |
---|
| 2438 | + obj->nr_extern > 0; |
---|
| 2439 | +} |
---|
| 2440 | + |
---|
| 2441 | +static bool kernel_needs_btf(const struct bpf_object *obj) |
---|
| 2442 | +{ |
---|
| 2443 | + return obj->efile.st_ops_shndx >= 0; |
---|
| 2444 | +} |
---|
| 2445 | + |
---|
| 2446 | +static int bpf_object__init_btf(struct bpf_object *obj, |
---|
| 2447 | + Elf_Data *btf_data, |
---|
| 2448 | + Elf_Data *btf_ext_data) |
---|
| 2449 | +{ |
---|
| 2450 | + int err = -ENOENT; |
---|
| 2451 | + |
---|
| 2452 | + if (btf_data) { |
---|
| 2453 | + obj->btf = btf__new(btf_data->d_buf, btf_data->d_size); |
---|
| 2454 | + if (IS_ERR(obj->btf)) { |
---|
| 2455 | + err = PTR_ERR(obj->btf); |
---|
| 2456 | + obj->btf = NULL; |
---|
| 2457 | + pr_warn("Error loading ELF section %s: %d.\n", |
---|
| 2458 | + BTF_ELF_SEC, err); |
---|
| 2459 | + goto out; |
---|
| 2460 | + } |
---|
| 2461 | + /* enforce 8-byte pointers for BPF-targeted BTFs */ |
---|
| 2462 | + btf__set_pointer_size(obj->btf, 8); |
---|
| 2463 | + err = 0; |
---|
| 2464 | + } |
---|
| 2465 | + if (btf_ext_data) { |
---|
| 2466 | + if (!obj->btf) { |
---|
| 2467 | + pr_debug("Ignore ELF section %s because its depending ELF section %s is not found.\n", |
---|
| 2468 | + BTF_EXT_ELF_SEC, BTF_ELF_SEC); |
---|
| 2469 | + goto out; |
---|
| 2470 | + } |
---|
| 2471 | + obj->btf_ext = btf_ext__new(btf_ext_data->d_buf, |
---|
| 2472 | + btf_ext_data->d_size); |
---|
| 2473 | + if (IS_ERR(obj->btf_ext)) { |
---|
| 2474 | + pr_warn("Error loading ELF section %s: %ld. Ignored and continue.\n", |
---|
| 2475 | + BTF_EXT_ELF_SEC, PTR_ERR(obj->btf_ext)); |
---|
| 2476 | + obj->btf_ext = NULL; |
---|
| 2477 | + goto out; |
---|
| 2478 | + } |
---|
| 2479 | + } |
---|
| 2480 | +out: |
---|
| 2481 | + if (err && libbpf_needs_btf(obj)) { |
---|
| 2482 | + pr_warn("BTF is required, but is missing or corrupted.\n"); |
---|
| 2483 | + return err; |
---|
| 2484 | + } |
---|
| 2485 | + return 0; |
---|
| 2486 | +} |
---|
| 2487 | + |
---|
| 2488 | +static int bpf_object__finalize_btf(struct bpf_object *obj) |
---|
| 2489 | +{ |
---|
| 2490 | + int err; |
---|
| 2491 | + |
---|
| 2492 | + if (!obj->btf) |
---|
| 2493 | + return 0; |
---|
| 2494 | + |
---|
| 2495 | + err = btf__finalize_data(obj, obj->btf); |
---|
| 2496 | + if (err) { |
---|
| 2497 | + pr_warn("Error finalizing %s: %d.\n", BTF_ELF_SEC, err); |
---|
| 2498 | + return err; |
---|
| 2499 | + } |
---|
| 2500 | + |
---|
| 2501 | + return 0; |
---|
| 2502 | +} |
---|
| 2503 | + |
---|
| 2504 | +static inline bool libbpf_prog_needs_vmlinux_btf(struct bpf_program *prog) |
---|
| 2505 | +{ |
---|
| 2506 | + if (prog->type == BPF_PROG_TYPE_STRUCT_OPS || |
---|
| 2507 | + prog->type == BPF_PROG_TYPE_LSM) |
---|
| 2508 | + return true; |
---|
| 2509 | + |
---|
| 2510 | + /* BPF_PROG_TYPE_TRACING programs which do not attach to other programs |
---|
| 2511 | + * also need vmlinux BTF |
---|
| 2512 | + */ |
---|
| 2513 | + if (prog->type == BPF_PROG_TYPE_TRACING && !prog->attach_prog_fd) |
---|
728 | 2514 | return true; |
---|
729 | 2515 | |
---|
730 | 2516 | return false; |
---|
731 | 2517 | } |
---|
732 | 2518 | |
---|
733 | | -static int bpf_object__elf_collect(struct bpf_object *obj) |
---|
| 2519 | +static int bpf_object__load_vmlinux_btf(struct bpf_object *obj) |
---|
734 | 2520 | { |
---|
735 | | - Elf *elf = obj->efile.elf; |
---|
736 | | - GElf_Ehdr *ep = &obj->efile.ehdr; |
---|
737 | | - Elf_Scn *scn = NULL; |
---|
738 | | - int idx = 0, err = 0; |
---|
| 2521 | + bool need_vmlinux_btf = false; |
---|
| 2522 | + struct bpf_program *prog; |
---|
| 2523 | + int i, err; |
---|
739 | 2524 | |
---|
740 | | - /* Elf is corrupted/truncated, avoid calling elf_strptr. */ |
---|
741 | | - if (!elf_rawdata(elf_getscn(elf, ep->e_shstrndx), NULL)) { |
---|
742 | | - pr_warning("failed to get e_shstrndx from %s\n", |
---|
743 | | - obj->path); |
---|
744 | | - return -LIBBPF_ERRNO__FORMAT; |
---|
| 2525 | + /* CO-RE relocations need kernel BTF */ |
---|
| 2526 | + if (obj->btf_ext && obj->btf_ext->core_relo_info.len) |
---|
| 2527 | + need_vmlinux_btf = true; |
---|
| 2528 | + |
---|
| 2529 | + /* Support for typed ksyms needs kernel BTF */ |
---|
| 2530 | + for (i = 0; i < obj->nr_extern; i++) { |
---|
| 2531 | + const struct extern_desc *ext; |
---|
| 2532 | + |
---|
| 2533 | + ext = &obj->externs[i]; |
---|
| 2534 | + if (ext->type == EXT_KSYM && ext->ksym.type_id) { |
---|
| 2535 | + need_vmlinux_btf = true; |
---|
| 2536 | + break; |
---|
| 2537 | + } |
---|
745 | 2538 | } |
---|
746 | 2539 | |
---|
747 | | - while ((scn = elf_nextscn(elf, scn)) != NULL) { |
---|
748 | | - char *name; |
---|
749 | | - GElf_Shdr sh; |
---|
750 | | - Elf_Data *data; |
---|
751 | | - |
---|
752 | | - idx++; |
---|
753 | | - if (gelf_getshdr(scn, &sh) != &sh) { |
---|
754 | | - pr_warning("failed to get section(%d) header from %s\n", |
---|
755 | | - idx, obj->path); |
---|
756 | | - err = -LIBBPF_ERRNO__FORMAT; |
---|
757 | | - goto out; |
---|
| 2540 | + bpf_object__for_each_program(prog, obj) { |
---|
| 2541 | + if (!prog->load) |
---|
| 2542 | + continue; |
---|
| 2543 | + if (libbpf_prog_needs_vmlinux_btf(prog)) { |
---|
| 2544 | + need_vmlinux_btf = true; |
---|
| 2545 | + break; |
---|
758 | 2546 | } |
---|
759 | | - |
---|
760 | | - name = elf_strptr(elf, ep->e_shstrndx, sh.sh_name); |
---|
761 | | - if (!name) { |
---|
762 | | - pr_warning("failed to get section(%d) name from %s\n", |
---|
763 | | - idx, obj->path); |
---|
764 | | - err = -LIBBPF_ERRNO__FORMAT; |
---|
765 | | - goto out; |
---|
766 | | - } |
---|
767 | | - |
---|
768 | | - data = elf_getdata(scn, 0); |
---|
769 | | - if (!data) { |
---|
770 | | - pr_warning("failed to get section(%d) data from %s(%s)\n", |
---|
771 | | - idx, name, obj->path); |
---|
772 | | - err = -LIBBPF_ERRNO__FORMAT; |
---|
773 | | - goto out; |
---|
774 | | - } |
---|
775 | | - pr_debug("section(%d) %s, size %ld, link %d, flags %lx, type=%d\n", |
---|
776 | | - idx, name, (unsigned long)data->d_size, |
---|
777 | | - (int)sh.sh_link, (unsigned long)sh.sh_flags, |
---|
778 | | - (int)sh.sh_type); |
---|
779 | | - |
---|
780 | | - if (strcmp(name, "license") == 0) |
---|
781 | | - err = bpf_object__init_license(obj, |
---|
782 | | - data->d_buf, |
---|
783 | | - data->d_size); |
---|
784 | | - else if (strcmp(name, "version") == 0) |
---|
785 | | - err = bpf_object__init_kversion(obj, |
---|
786 | | - data->d_buf, |
---|
787 | | - data->d_size); |
---|
788 | | - else if (strcmp(name, "maps") == 0) |
---|
789 | | - obj->efile.maps_shndx = idx; |
---|
790 | | - else if (strcmp(name, BTF_ELF_SEC) == 0) { |
---|
791 | | - obj->btf = btf__new(data->d_buf, data->d_size, |
---|
792 | | - __pr_debug); |
---|
793 | | - if (IS_ERR(obj->btf)) { |
---|
794 | | - pr_warning("Error loading ELF section %s: %ld. Ignored and continue.\n", |
---|
795 | | - BTF_ELF_SEC, PTR_ERR(obj->btf)); |
---|
796 | | - obj->btf = NULL; |
---|
797 | | - } |
---|
798 | | - } else if (sh.sh_type == SHT_SYMTAB) { |
---|
799 | | - if (obj->efile.symbols) { |
---|
800 | | - pr_warning("bpf: multiple SYMTAB in %s\n", |
---|
801 | | - obj->path); |
---|
802 | | - err = -LIBBPF_ERRNO__FORMAT; |
---|
803 | | - } else { |
---|
804 | | - obj->efile.symbols = data; |
---|
805 | | - obj->efile.strtabidx = sh.sh_link; |
---|
806 | | - } |
---|
807 | | - } else if ((sh.sh_type == SHT_PROGBITS) && |
---|
808 | | - (sh.sh_flags & SHF_EXECINSTR) && |
---|
809 | | - (data->d_size > 0)) { |
---|
810 | | - if (strcmp(name, ".text") == 0) |
---|
811 | | - obj->efile.text_shndx = idx; |
---|
812 | | - err = bpf_object__add_program(obj, data->d_buf, |
---|
813 | | - data->d_size, name, idx); |
---|
814 | | - if (err) { |
---|
815 | | - char errmsg[STRERR_BUFSIZE]; |
---|
816 | | - char *cp = str_error(-err, errmsg, sizeof(errmsg)); |
---|
817 | | - |
---|
818 | | - pr_warning("failed to alloc program %s (%s): %s", |
---|
819 | | - name, obj->path, cp); |
---|
820 | | - } |
---|
821 | | - } else if (sh.sh_type == SHT_REL) { |
---|
822 | | - void *reloc = obj->efile.reloc; |
---|
823 | | - int nr_reloc = obj->efile.nr_reloc + 1; |
---|
824 | | - int sec = sh.sh_info; /* points to other section */ |
---|
825 | | - |
---|
826 | | - /* Only do relo for section with exec instructions */ |
---|
827 | | - if (!section_have_execinstr(obj, sec)) { |
---|
828 | | - pr_debug("skip relo %s(%d) for section(%d)\n", |
---|
829 | | - name, idx, sec); |
---|
830 | | - continue; |
---|
831 | | - } |
---|
832 | | - |
---|
833 | | - reloc = reallocarray(reloc, nr_reloc, |
---|
834 | | - sizeof(*obj->efile.reloc)); |
---|
835 | | - if (!reloc) { |
---|
836 | | - pr_warning("realloc failed\n"); |
---|
837 | | - err = -ENOMEM; |
---|
838 | | - } else { |
---|
839 | | - int n = nr_reloc - 1; |
---|
840 | | - |
---|
841 | | - obj->efile.reloc = reloc; |
---|
842 | | - obj->efile.nr_reloc = nr_reloc; |
---|
843 | | - |
---|
844 | | - obj->efile.reloc[n].shdr = sh; |
---|
845 | | - obj->efile.reloc[n].data = data; |
---|
846 | | - } |
---|
847 | | - } else { |
---|
848 | | - pr_debug("skip section(%d) %s\n", idx, name); |
---|
849 | | - } |
---|
850 | | - if (err) |
---|
851 | | - goto out; |
---|
852 | 2547 | } |
---|
853 | 2548 | |
---|
854 | | - if (!obj->efile.strtabidx || obj->efile.strtabidx >= idx) { |
---|
855 | | - pr_warning("Corrupted ELF file: index of strtab invalid\n"); |
---|
856 | | - return LIBBPF_ERRNO__FORMAT; |
---|
| 2549 | + if (!need_vmlinux_btf) |
---|
| 2550 | + return 0; |
---|
| 2551 | + |
---|
| 2552 | + obj->btf_vmlinux = libbpf_find_kernel_btf(); |
---|
| 2553 | + if (IS_ERR(obj->btf_vmlinux)) { |
---|
| 2554 | + err = PTR_ERR(obj->btf_vmlinux); |
---|
| 2555 | + pr_warn("Error loading vmlinux BTF: %d\n", err); |
---|
| 2556 | + obj->btf_vmlinux = NULL; |
---|
| 2557 | + return err; |
---|
857 | 2558 | } |
---|
858 | | - if (obj->efile.maps_shndx >= 0) { |
---|
859 | | - err = bpf_object__init_maps(obj); |
---|
860 | | - if (err) |
---|
861 | | - goto out; |
---|
| 2559 | + return 0; |
---|
| 2560 | +} |
---|
| 2561 | + |
---|
| 2562 | +static int bpf_object__sanitize_and_load_btf(struct bpf_object *obj) |
---|
| 2563 | +{ |
---|
| 2564 | + struct btf *kern_btf = obj->btf; |
---|
| 2565 | + bool btf_mandatory, sanitize; |
---|
| 2566 | + int err = 0; |
---|
| 2567 | + |
---|
| 2568 | + if (!obj->btf) |
---|
| 2569 | + return 0; |
---|
| 2570 | + |
---|
| 2571 | + if (!kernel_supports(FEAT_BTF)) { |
---|
| 2572 | + if (kernel_needs_btf(obj)) { |
---|
| 2573 | + err = -EOPNOTSUPP; |
---|
| 2574 | + goto report; |
---|
| 2575 | + } |
---|
| 2576 | + pr_debug("Kernel doesn't support BTF, skipping uploading it.\n"); |
---|
| 2577 | + return 0; |
---|
862 | 2578 | } |
---|
863 | | - err = bpf_object__init_prog_names(obj); |
---|
864 | | -out: |
---|
| 2579 | + |
---|
| 2580 | + sanitize = btf_needs_sanitization(obj); |
---|
| 2581 | + if (sanitize) { |
---|
| 2582 | + const void *raw_data; |
---|
| 2583 | + __u32 sz; |
---|
| 2584 | + |
---|
| 2585 | + /* clone BTF to sanitize a copy and leave the original intact */ |
---|
| 2586 | + raw_data = btf__get_raw_data(obj->btf, &sz); |
---|
| 2587 | + kern_btf = btf__new(raw_data, sz); |
---|
| 2588 | + if (IS_ERR(kern_btf)) |
---|
| 2589 | + return PTR_ERR(kern_btf); |
---|
| 2590 | + |
---|
| 2591 | + /* enforce 8-byte pointers for BPF-targeted BTFs */ |
---|
| 2592 | + btf__set_pointer_size(obj->btf, 8); |
---|
| 2593 | + bpf_object__sanitize_btf(obj, kern_btf); |
---|
| 2594 | + } |
---|
| 2595 | + |
---|
| 2596 | + err = btf__load(kern_btf); |
---|
| 2597 | + if (sanitize) { |
---|
| 2598 | + if (!err) { |
---|
| 2599 | + /* move fd to libbpf's BTF */ |
---|
| 2600 | + btf__set_fd(obj->btf, btf__fd(kern_btf)); |
---|
| 2601 | + btf__set_fd(kern_btf, -1); |
---|
| 2602 | + } |
---|
| 2603 | + btf__free(kern_btf); |
---|
| 2604 | + } |
---|
| 2605 | +report: |
---|
| 2606 | + if (err) { |
---|
| 2607 | + btf_mandatory = kernel_needs_btf(obj); |
---|
| 2608 | + pr_warn("Error loading .BTF into kernel: %d. %s\n", err, |
---|
| 2609 | + btf_mandatory ? "BTF is mandatory, can't proceed." |
---|
| 2610 | + : "BTF is optional, ignoring."); |
---|
| 2611 | + if (!btf_mandatory) |
---|
| 2612 | + err = 0; |
---|
| 2613 | + } |
---|
865 | 2614 | return err; |
---|
866 | 2615 | } |
---|
867 | 2616 | |
---|
868 | | -static struct bpf_program * |
---|
869 | | -bpf_object__find_prog_by_idx(struct bpf_object *obj, int idx) |
---|
| 2617 | +static const char *elf_sym_str(const struct bpf_object *obj, size_t off) |
---|
870 | 2618 | { |
---|
871 | | - struct bpf_program *prog; |
---|
872 | | - size_t i; |
---|
| 2619 | + const char *name; |
---|
873 | 2620 | |
---|
874 | | - for (i = 0; i < obj->nr_programs; i++) { |
---|
875 | | - prog = &obj->programs[i]; |
---|
876 | | - if (prog->idx == idx) |
---|
877 | | - return prog; |
---|
| 2621 | + name = elf_strptr(obj->efile.elf, obj->efile.strtabidx, off); |
---|
| 2622 | + if (!name) { |
---|
| 2623 | + pr_warn("elf: failed to get section name string at offset %zu from %s: %s\n", |
---|
| 2624 | + off, obj->path, elf_errmsg(-1)); |
---|
| 2625 | + return NULL; |
---|
| 2626 | + } |
---|
| 2627 | + |
---|
| 2628 | + return name; |
---|
| 2629 | +} |
---|
| 2630 | + |
---|
| 2631 | +static const char *elf_sec_str(const struct bpf_object *obj, size_t off) |
---|
| 2632 | +{ |
---|
| 2633 | + const char *name; |
---|
| 2634 | + |
---|
| 2635 | + name = elf_strptr(obj->efile.elf, obj->efile.shstrndx, off); |
---|
| 2636 | + if (!name) { |
---|
| 2637 | + pr_warn("elf: failed to get section name string at offset %zu from %s: %s\n", |
---|
| 2638 | + off, obj->path, elf_errmsg(-1)); |
---|
| 2639 | + return NULL; |
---|
| 2640 | + } |
---|
| 2641 | + |
---|
| 2642 | + return name; |
---|
| 2643 | +} |
---|
| 2644 | + |
---|
| 2645 | +static Elf_Scn *elf_sec_by_idx(const struct bpf_object *obj, size_t idx) |
---|
| 2646 | +{ |
---|
| 2647 | + Elf_Scn *scn; |
---|
| 2648 | + |
---|
| 2649 | + scn = elf_getscn(obj->efile.elf, idx); |
---|
| 2650 | + if (!scn) { |
---|
| 2651 | + pr_warn("elf: failed to get section(%zu) from %s: %s\n", |
---|
| 2652 | + idx, obj->path, elf_errmsg(-1)); |
---|
| 2653 | + return NULL; |
---|
| 2654 | + } |
---|
| 2655 | + return scn; |
---|
| 2656 | +} |
---|
| 2657 | + |
---|
| 2658 | +static Elf_Scn *elf_sec_by_name(const struct bpf_object *obj, const char *name) |
---|
| 2659 | +{ |
---|
| 2660 | + Elf_Scn *scn = NULL; |
---|
| 2661 | + Elf *elf = obj->efile.elf; |
---|
| 2662 | + const char *sec_name; |
---|
| 2663 | + |
---|
| 2664 | + while ((scn = elf_nextscn(elf, scn)) != NULL) { |
---|
| 2665 | + sec_name = elf_sec_name(obj, scn); |
---|
| 2666 | + if (!sec_name) |
---|
| 2667 | + return NULL; |
---|
| 2668 | + |
---|
| 2669 | + if (strcmp(sec_name, name) != 0) |
---|
| 2670 | + continue; |
---|
| 2671 | + |
---|
| 2672 | + return scn; |
---|
878 | 2673 | } |
---|
879 | 2674 | return NULL; |
---|
880 | 2675 | } |
---|
881 | 2676 | |
---|
| 2677 | +static int elf_sec_hdr(const struct bpf_object *obj, Elf_Scn *scn, GElf_Shdr *hdr) |
---|
| 2678 | +{ |
---|
| 2679 | + if (!scn) |
---|
| 2680 | + return -EINVAL; |
---|
| 2681 | + |
---|
| 2682 | + if (gelf_getshdr(scn, hdr) != hdr) { |
---|
| 2683 | + pr_warn("elf: failed to get section(%zu) header from %s: %s\n", |
---|
| 2684 | + elf_ndxscn(scn), obj->path, elf_errmsg(-1)); |
---|
| 2685 | + return -EINVAL; |
---|
| 2686 | + } |
---|
| 2687 | + |
---|
| 2688 | + return 0; |
---|
| 2689 | +} |
---|
| 2690 | + |
---|
| 2691 | +static const char *elf_sec_name(const struct bpf_object *obj, Elf_Scn *scn) |
---|
| 2692 | +{ |
---|
| 2693 | + const char *name; |
---|
| 2694 | + GElf_Shdr sh; |
---|
| 2695 | + |
---|
| 2696 | + if (!scn) |
---|
| 2697 | + return NULL; |
---|
| 2698 | + |
---|
| 2699 | + if (elf_sec_hdr(obj, scn, &sh)) |
---|
| 2700 | + return NULL; |
---|
| 2701 | + |
---|
| 2702 | + name = elf_sec_str(obj, sh.sh_name); |
---|
| 2703 | + if (!name) { |
---|
| 2704 | + pr_warn("elf: failed to get section(%zu) name from %s: %s\n", |
---|
| 2705 | + elf_ndxscn(scn), obj->path, elf_errmsg(-1)); |
---|
| 2706 | + return NULL; |
---|
| 2707 | + } |
---|
| 2708 | + |
---|
| 2709 | + return name; |
---|
| 2710 | +} |
---|
| 2711 | + |
---|
| 2712 | +static Elf_Data *elf_sec_data(const struct bpf_object *obj, Elf_Scn *scn) |
---|
| 2713 | +{ |
---|
| 2714 | + Elf_Data *data; |
---|
| 2715 | + |
---|
| 2716 | + if (!scn) |
---|
| 2717 | + return NULL; |
---|
| 2718 | + |
---|
| 2719 | + data = elf_getdata(scn, 0); |
---|
| 2720 | + if (!data) { |
---|
| 2721 | + pr_warn("elf: failed to get section(%zu) %s data from %s: %s\n", |
---|
| 2722 | + elf_ndxscn(scn), elf_sec_name(obj, scn) ?: "<?>", |
---|
| 2723 | + obj->path, elf_errmsg(-1)); |
---|
| 2724 | + return NULL; |
---|
| 2725 | + } |
---|
| 2726 | + |
---|
| 2727 | + return data; |
---|
| 2728 | +} |
---|
| 2729 | + |
---|
| 2730 | +static int elf_sym_by_sec_off(const struct bpf_object *obj, size_t sec_idx, |
---|
| 2731 | + size_t off, __u32 sym_type, GElf_Sym *sym) |
---|
| 2732 | +{ |
---|
| 2733 | + Elf_Data *symbols = obj->efile.symbols; |
---|
| 2734 | + size_t n = symbols->d_size / sizeof(GElf_Sym); |
---|
| 2735 | + int i; |
---|
| 2736 | + |
---|
| 2737 | + for (i = 0; i < n; i++) { |
---|
| 2738 | + if (!gelf_getsym(symbols, i, sym)) |
---|
| 2739 | + continue; |
---|
| 2740 | + if (sym->st_shndx != sec_idx || sym->st_value != off) |
---|
| 2741 | + continue; |
---|
| 2742 | + if (GELF_ST_TYPE(sym->st_info) != sym_type) |
---|
| 2743 | + continue; |
---|
| 2744 | + return 0; |
---|
| 2745 | + } |
---|
| 2746 | + |
---|
| 2747 | + return -ENOENT; |
---|
| 2748 | +} |
---|
| 2749 | + |
---|
| 2750 | +static bool is_sec_name_dwarf(const char *name) |
---|
| 2751 | +{ |
---|
| 2752 | + /* approximation, but the actual list is too long */ |
---|
| 2753 | + return strncmp(name, ".debug_", sizeof(".debug_") - 1) == 0; |
---|
| 2754 | +} |
---|
| 2755 | + |
---|
| 2756 | +static bool ignore_elf_section(GElf_Shdr *hdr, const char *name) |
---|
| 2757 | +{ |
---|
| 2758 | + /* no special handling of .strtab */ |
---|
| 2759 | + if (hdr->sh_type == SHT_STRTAB) |
---|
| 2760 | + return true; |
---|
| 2761 | + |
---|
| 2762 | + /* ignore .llvm_addrsig section as well */ |
---|
| 2763 | + if (hdr->sh_type == 0x6FFF4C03 /* SHT_LLVM_ADDRSIG */) |
---|
| 2764 | + return true; |
---|
| 2765 | + |
---|
| 2766 | + /* no subprograms will lead to an empty .text section, ignore it */ |
---|
| 2767 | + if (hdr->sh_type == SHT_PROGBITS && hdr->sh_size == 0 && |
---|
| 2768 | + strcmp(name, ".text") == 0) |
---|
| 2769 | + return true; |
---|
| 2770 | + |
---|
| 2771 | + /* DWARF sections */ |
---|
| 2772 | + if (is_sec_name_dwarf(name)) |
---|
| 2773 | + return true; |
---|
| 2774 | + |
---|
| 2775 | + if (strncmp(name, ".rel", sizeof(".rel") - 1) == 0) { |
---|
| 2776 | + name += sizeof(".rel") - 1; |
---|
| 2777 | + /* DWARF section relocations */ |
---|
| 2778 | + if (is_sec_name_dwarf(name)) |
---|
| 2779 | + return true; |
---|
| 2780 | + |
---|
| 2781 | + /* .BTF and .BTF.ext don't need relocations */ |
---|
| 2782 | + if (strcmp(name, BTF_ELF_SEC) == 0 || |
---|
| 2783 | + strcmp(name, BTF_EXT_ELF_SEC) == 0) |
---|
| 2784 | + return true; |
---|
| 2785 | + } |
---|
| 2786 | + |
---|
| 2787 | + return false; |
---|
| 2788 | +} |
---|
| 2789 | + |
---|
| 2790 | +static int cmp_progs(const void *_a, const void *_b) |
---|
| 2791 | +{ |
---|
| 2792 | + const struct bpf_program *a = _a; |
---|
| 2793 | + const struct bpf_program *b = _b; |
---|
| 2794 | + |
---|
| 2795 | + if (a->sec_idx != b->sec_idx) |
---|
| 2796 | + return a->sec_idx < b->sec_idx ? -1 : 1; |
---|
| 2797 | + |
---|
| 2798 | + /* sec_insn_off can't be the same within the section */ |
---|
| 2799 | + return a->sec_insn_off < b->sec_insn_off ? -1 : 1; |
---|
| 2800 | +} |
---|
| 2801 | + |
---|
| 2802 | +static int bpf_object__elf_collect(struct bpf_object *obj) |
---|
| 2803 | +{ |
---|
| 2804 | + Elf *elf = obj->efile.elf; |
---|
| 2805 | + Elf_Data *btf_ext_data = NULL; |
---|
| 2806 | + Elf_Data *btf_data = NULL; |
---|
| 2807 | + int idx = 0, err = 0; |
---|
| 2808 | + const char *name; |
---|
| 2809 | + Elf_Data *data; |
---|
| 2810 | + Elf_Scn *scn; |
---|
| 2811 | + GElf_Shdr sh; |
---|
| 2812 | + |
---|
| 2813 | + /* a bunch of ELF parsing functionality depends on processing symbols, |
---|
| 2814 | + * so do the first pass and find the symbol table |
---|
| 2815 | + */ |
---|
| 2816 | + scn = NULL; |
---|
| 2817 | + while ((scn = elf_nextscn(elf, scn)) != NULL) { |
---|
| 2818 | + if (elf_sec_hdr(obj, scn, &sh)) |
---|
| 2819 | + return -LIBBPF_ERRNO__FORMAT; |
---|
| 2820 | + |
---|
| 2821 | + if (sh.sh_type == SHT_SYMTAB) { |
---|
| 2822 | + if (obj->efile.symbols) { |
---|
| 2823 | + pr_warn("elf: multiple symbol tables in %s\n", obj->path); |
---|
| 2824 | + return -LIBBPF_ERRNO__FORMAT; |
---|
| 2825 | + } |
---|
| 2826 | + |
---|
| 2827 | + data = elf_sec_data(obj, scn); |
---|
| 2828 | + if (!data) |
---|
| 2829 | + return -LIBBPF_ERRNO__FORMAT; |
---|
| 2830 | + |
---|
| 2831 | + obj->efile.symbols = data; |
---|
| 2832 | + obj->efile.symbols_shndx = elf_ndxscn(scn); |
---|
| 2833 | + obj->efile.strtabidx = sh.sh_link; |
---|
| 2834 | + } |
---|
| 2835 | + } |
---|
| 2836 | + |
---|
| 2837 | + scn = NULL; |
---|
| 2838 | + while ((scn = elf_nextscn(elf, scn)) != NULL) { |
---|
| 2839 | + idx++; |
---|
| 2840 | + |
---|
| 2841 | + if (elf_sec_hdr(obj, scn, &sh)) |
---|
| 2842 | + return -LIBBPF_ERRNO__FORMAT; |
---|
| 2843 | + |
---|
| 2844 | + name = elf_sec_str(obj, sh.sh_name); |
---|
| 2845 | + if (!name) |
---|
| 2846 | + return -LIBBPF_ERRNO__FORMAT; |
---|
| 2847 | + |
---|
| 2848 | + if (ignore_elf_section(&sh, name)) |
---|
| 2849 | + continue; |
---|
| 2850 | + |
---|
| 2851 | + data = elf_sec_data(obj, scn); |
---|
| 2852 | + if (!data) |
---|
| 2853 | + return -LIBBPF_ERRNO__FORMAT; |
---|
| 2854 | + |
---|
| 2855 | + pr_debug("elf: section(%d) %s, size %ld, link %d, flags %lx, type=%d\n", |
---|
| 2856 | + idx, name, (unsigned long)data->d_size, |
---|
| 2857 | + (int)sh.sh_link, (unsigned long)sh.sh_flags, |
---|
| 2858 | + (int)sh.sh_type); |
---|
| 2859 | + |
---|
| 2860 | + if (strcmp(name, "license") == 0) { |
---|
| 2861 | + err = bpf_object__init_license(obj, data->d_buf, data->d_size); |
---|
| 2862 | + if (err) |
---|
| 2863 | + return err; |
---|
| 2864 | + } else if (strcmp(name, "version") == 0) { |
---|
| 2865 | + err = bpf_object__init_kversion(obj, data->d_buf, data->d_size); |
---|
| 2866 | + if (err) |
---|
| 2867 | + return err; |
---|
| 2868 | + } else if (strcmp(name, "maps") == 0) { |
---|
| 2869 | + obj->efile.maps_shndx = idx; |
---|
| 2870 | + } else if (strcmp(name, MAPS_ELF_SEC) == 0) { |
---|
| 2871 | + obj->efile.btf_maps_shndx = idx; |
---|
| 2872 | + } else if (strcmp(name, BTF_ELF_SEC) == 0) { |
---|
| 2873 | + btf_data = data; |
---|
| 2874 | + } else if (strcmp(name, BTF_EXT_ELF_SEC) == 0) { |
---|
| 2875 | + btf_ext_data = data; |
---|
| 2876 | + } else if (sh.sh_type == SHT_SYMTAB) { |
---|
| 2877 | + /* already processed during the first pass above */ |
---|
| 2878 | + } else if (sh.sh_type == SHT_PROGBITS && data->d_size > 0) { |
---|
| 2879 | + if (sh.sh_flags & SHF_EXECINSTR) { |
---|
| 2880 | + if (strcmp(name, ".text") == 0) |
---|
| 2881 | + obj->efile.text_shndx = idx; |
---|
| 2882 | + err = bpf_object__add_programs(obj, data, name, idx); |
---|
| 2883 | + if (err) |
---|
| 2884 | + return err; |
---|
| 2885 | + } else if (strcmp(name, DATA_SEC) == 0) { |
---|
| 2886 | + obj->efile.data = data; |
---|
| 2887 | + obj->efile.data_shndx = idx; |
---|
| 2888 | + } else if (strcmp(name, RODATA_SEC) == 0) { |
---|
| 2889 | + obj->efile.rodata = data; |
---|
| 2890 | + obj->efile.rodata_shndx = idx; |
---|
| 2891 | + } else if (strcmp(name, STRUCT_OPS_SEC) == 0) { |
---|
| 2892 | + obj->efile.st_ops_data = data; |
---|
| 2893 | + obj->efile.st_ops_shndx = idx; |
---|
| 2894 | + } else { |
---|
| 2895 | + pr_info("elf: skipping unrecognized data section(%d) %s\n", |
---|
| 2896 | + idx, name); |
---|
| 2897 | + } |
---|
| 2898 | + } else if (sh.sh_type == SHT_REL) { |
---|
| 2899 | + int nr_sects = obj->efile.nr_reloc_sects; |
---|
| 2900 | + void *sects = obj->efile.reloc_sects; |
---|
| 2901 | + int sec = sh.sh_info; /* points to other section */ |
---|
| 2902 | + |
---|
| 2903 | + /* Only do relo for section with exec instructions */ |
---|
| 2904 | + if (!section_have_execinstr(obj, sec) && |
---|
| 2905 | + strcmp(name, ".rel" STRUCT_OPS_SEC) && |
---|
| 2906 | + strcmp(name, ".rel" MAPS_ELF_SEC)) { |
---|
| 2907 | + pr_info("elf: skipping relo section(%d) %s for section(%d) %s\n", |
---|
| 2908 | + idx, name, sec, |
---|
| 2909 | + elf_sec_name(obj, elf_sec_by_idx(obj, sec)) ?: "<?>"); |
---|
| 2910 | + continue; |
---|
| 2911 | + } |
---|
| 2912 | + |
---|
| 2913 | + sects = libbpf_reallocarray(sects, nr_sects + 1, |
---|
| 2914 | + sizeof(*obj->efile.reloc_sects)); |
---|
| 2915 | + if (!sects) |
---|
| 2916 | + return -ENOMEM; |
---|
| 2917 | + |
---|
| 2918 | + obj->efile.reloc_sects = sects; |
---|
| 2919 | + obj->efile.nr_reloc_sects++; |
---|
| 2920 | + |
---|
| 2921 | + obj->efile.reloc_sects[nr_sects].shdr = sh; |
---|
| 2922 | + obj->efile.reloc_sects[nr_sects].data = data; |
---|
| 2923 | + } else if (sh.sh_type == SHT_NOBITS && strcmp(name, BSS_SEC) == 0) { |
---|
| 2924 | + obj->efile.bss = data; |
---|
| 2925 | + obj->efile.bss_shndx = idx; |
---|
| 2926 | + } else { |
---|
| 2927 | + pr_info("elf: skipping section(%d) %s (size %zu)\n", idx, name, |
---|
| 2928 | + (size_t)sh.sh_size); |
---|
| 2929 | + } |
---|
| 2930 | + } |
---|
| 2931 | + |
---|
| 2932 | + if (!obj->efile.strtabidx || obj->efile.strtabidx > idx) { |
---|
| 2933 | + pr_warn("elf: symbol strings section missing or invalid in %s\n", obj->path); |
---|
| 2934 | + return -LIBBPF_ERRNO__FORMAT; |
---|
| 2935 | + } |
---|
| 2936 | + |
---|
| 2937 | + /* sort BPF programs by section name and in-section instruction offset |
---|
| 2938 | + * for faster search */ |
---|
| 2939 | + qsort(obj->programs, obj->nr_programs, sizeof(*obj->programs), cmp_progs); |
---|
| 2940 | + |
---|
| 2941 | + return bpf_object__init_btf(obj, btf_data, btf_ext_data); |
---|
| 2942 | +} |
---|
| 2943 | + |
---|
| 2944 | +static bool sym_is_extern(const GElf_Sym *sym) |
---|
| 2945 | +{ |
---|
| 2946 | + int bind = GELF_ST_BIND(sym->st_info); |
---|
| 2947 | + /* externs are symbols w/ type=NOTYPE, bind=GLOBAL|WEAK, section=UND */ |
---|
| 2948 | + return sym->st_shndx == SHN_UNDEF && |
---|
| 2949 | + (bind == STB_GLOBAL || bind == STB_WEAK) && |
---|
| 2950 | + GELF_ST_TYPE(sym->st_info) == STT_NOTYPE; |
---|
| 2951 | +} |
---|
| 2952 | + |
---|
| 2953 | +static int find_extern_btf_id(const struct btf *btf, const char *ext_name) |
---|
| 2954 | +{ |
---|
| 2955 | + const struct btf_type *t; |
---|
| 2956 | + const char *var_name; |
---|
| 2957 | + int i, n; |
---|
| 2958 | + |
---|
| 2959 | + if (!btf) |
---|
| 2960 | + return -ESRCH; |
---|
| 2961 | + |
---|
| 2962 | + n = btf__get_nr_types(btf); |
---|
| 2963 | + for (i = 1; i <= n; i++) { |
---|
| 2964 | + t = btf__type_by_id(btf, i); |
---|
| 2965 | + |
---|
| 2966 | + if (!btf_is_var(t)) |
---|
| 2967 | + continue; |
---|
| 2968 | + |
---|
| 2969 | + var_name = btf__name_by_offset(btf, t->name_off); |
---|
| 2970 | + if (strcmp(var_name, ext_name)) |
---|
| 2971 | + continue; |
---|
| 2972 | + |
---|
| 2973 | + if (btf_var(t)->linkage != BTF_VAR_GLOBAL_EXTERN) |
---|
| 2974 | + return -EINVAL; |
---|
| 2975 | + |
---|
| 2976 | + return i; |
---|
| 2977 | + } |
---|
| 2978 | + |
---|
| 2979 | + return -ENOENT; |
---|
| 2980 | +} |
---|
| 2981 | + |
---|
| 2982 | +static int find_extern_sec_btf_id(struct btf *btf, int ext_btf_id) { |
---|
| 2983 | + const struct btf_var_secinfo *vs; |
---|
| 2984 | + const struct btf_type *t; |
---|
| 2985 | + int i, j, n; |
---|
| 2986 | + |
---|
| 2987 | + if (!btf) |
---|
| 2988 | + return -ESRCH; |
---|
| 2989 | + |
---|
| 2990 | + n = btf__get_nr_types(btf); |
---|
| 2991 | + for (i = 1; i <= n; i++) { |
---|
| 2992 | + t = btf__type_by_id(btf, i); |
---|
| 2993 | + |
---|
| 2994 | + if (!btf_is_datasec(t)) |
---|
| 2995 | + continue; |
---|
| 2996 | + |
---|
| 2997 | + vs = btf_var_secinfos(t); |
---|
| 2998 | + for (j = 0; j < btf_vlen(t); j++, vs++) { |
---|
| 2999 | + if (vs->type == ext_btf_id) |
---|
| 3000 | + return i; |
---|
| 3001 | + } |
---|
| 3002 | + } |
---|
| 3003 | + |
---|
| 3004 | + return -ENOENT; |
---|
| 3005 | +} |
---|
| 3006 | + |
---|
| 3007 | +static enum kcfg_type find_kcfg_type(const struct btf *btf, int id, |
---|
| 3008 | + bool *is_signed) |
---|
| 3009 | +{ |
---|
| 3010 | + const struct btf_type *t; |
---|
| 3011 | + const char *name; |
---|
| 3012 | + |
---|
| 3013 | + t = skip_mods_and_typedefs(btf, id, NULL); |
---|
| 3014 | + name = btf__name_by_offset(btf, t->name_off); |
---|
| 3015 | + |
---|
| 3016 | + if (is_signed) |
---|
| 3017 | + *is_signed = false; |
---|
| 3018 | + switch (btf_kind(t)) { |
---|
| 3019 | + case BTF_KIND_INT: { |
---|
| 3020 | + int enc = btf_int_encoding(t); |
---|
| 3021 | + |
---|
| 3022 | + if (enc & BTF_INT_BOOL) |
---|
| 3023 | + return t->size == 1 ? KCFG_BOOL : KCFG_UNKNOWN; |
---|
| 3024 | + if (is_signed) |
---|
| 3025 | + *is_signed = enc & BTF_INT_SIGNED; |
---|
| 3026 | + if (t->size == 1) |
---|
| 3027 | + return KCFG_CHAR; |
---|
| 3028 | + if (t->size < 1 || t->size > 8 || (t->size & (t->size - 1))) |
---|
| 3029 | + return KCFG_UNKNOWN; |
---|
| 3030 | + return KCFG_INT; |
---|
| 3031 | + } |
---|
| 3032 | + case BTF_KIND_ENUM: |
---|
| 3033 | + if (t->size != 4) |
---|
| 3034 | + return KCFG_UNKNOWN; |
---|
| 3035 | + if (strcmp(name, "libbpf_tristate")) |
---|
| 3036 | + return KCFG_UNKNOWN; |
---|
| 3037 | + return KCFG_TRISTATE; |
---|
| 3038 | + case BTF_KIND_ARRAY: |
---|
| 3039 | + if (btf_array(t)->nelems == 0) |
---|
| 3040 | + return KCFG_UNKNOWN; |
---|
| 3041 | + if (find_kcfg_type(btf, btf_array(t)->type, NULL) != KCFG_CHAR) |
---|
| 3042 | + return KCFG_UNKNOWN; |
---|
| 3043 | + return KCFG_CHAR_ARR; |
---|
| 3044 | + default: |
---|
| 3045 | + return KCFG_UNKNOWN; |
---|
| 3046 | + } |
---|
| 3047 | +} |
---|
| 3048 | + |
---|
| 3049 | +static int cmp_externs(const void *_a, const void *_b) |
---|
| 3050 | +{ |
---|
| 3051 | + const struct extern_desc *a = _a; |
---|
| 3052 | + const struct extern_desc *b = _b; |
---|
| 3053 | + |
---|
| 3054 | + if (a->type != b->type) |
---|
| 3055 | + return a->type < b->type ? -1 : 1; |
---|
| 3056 | + |
---|
| 3057 | + if (a->type == EXT_KCFG) { |
---|
| 3058 | + /* descending order by alignment requirements */ |
---|
| 3059 | + if (a->kcfg.align != b->kcfg.align) |
---|
| 3060 | + return a->kcfg.align > b->kcfg.align ? -1 : 1; |
---|
| 3061 | + /* ascending order by size, within same alignment class */ |
---|
| 3062 | + if (a->kcfg.sz != b->kcfg.sz) |
---|
| 3063 | + return a->kcfg.sz < b->kcfg.sz ? -1 : 1; |
---|
| 3064 | + } |
---|
| 3065 | + |
---|
| 3066 | + /* resolve ties by name */ |
---|
| 3067 | + return strcmp(a->name, b->name); |
---|
| 3068 | +} |
---|
| 3069 | + |
---|
| 3070 | +static int find_int_btf_id(const struct btf *btf) |
---|
| 3071 | +{ |
---|
| 3072 | + const struct btf_type *t; |
---|
| 3073 | + int i, n; |
---|
| 3074 | + |
---|
| 3075 | + n = btf__get_nr_types(btf); |
---|
| 3076 | + for (i = 1; i <= n; i++) { |
---|
| 3077 | + t = btf__type_by_id(btf, i); |
---|
| 3078 | + |
---|
| 3079 | + if (btf_is_int(t) && btf_int_bits(t) == 32) |
---|
| 3080 | + return i; |
---|
| 3081 | + } |
---|
| 3082 | + |
---|
| 3083 | + return 0; |
---|
| 3084 | +} |
---|
| 3085 | + |
---|
| 3086 | +static int bpf_object__collect_externs(struct bpf_object *obj) |
---|
| 3087 | +{ |
---|
| 3088 | + struct btf_type *sec, *kcfg_sec = NULL, *ksym_sec = NULL; |
---|
| 3089 | + const struct btf_type *t; |
---|
| 3090 | + struct extern_desc *ext; |
---|
| 3091 | + int i, n, off; |
---|
| 3092 | + const char *ext_name, *sec_name; |
---|
| 3093 | + Elf_Scn *scn; |
---|
| 3094 | + GElf_Shdr sh; |
---|
| 3095 | + |
---|
| 3096 | + if (!obj->efile.symbols) |
---|
| 3097 | + return 0; |
---|
| 3098 | + |
---|
| 3099 | + scn = elf_sec_by_idx(obj, obj->efile.symbols_shndx); |
---|
| 3100 | + if (elf_sec_hdr(obj, scn, &sh)) |
---|
| 3101 | + return -LIBBPF_ERRNO__FORMAT; |
---|
| 3102 | + |
---|
| 3103 | + n = sh.sh_size / sh.sh_entsize; |
---|
| 3104 | + pr_debug("looking for externs among %d symbols...\n", n); |
---|
| 3105 | + |
---|
| 3106 | + for (i = 0; i < n; i++) { |
---|
| 3107 | + GElf_Sym sym; |
---|
| 3108 | + |
---|
| 3109 | + if (!gelf_getsym(obj->efile.symbols, i, &sym)) |
---|
| 3110 | + return -LIBBPF_ERRNO__FORMAT; |
---|
| 3111 | + if (!sym_is_extern(&sym)) |
---|
| 3112 | + continue; |
---|
| 3113 | + ext_name = elf_sym_str(obj, sym.st_name); |
---|
| 3114 | + if (!ext_name || !ext_name[0]) |
---|
| 3115 | + continue; |
---|
| 3116 | + |
---|
| 3117 | + ext = obj->externs; |
---|
| 3118 | + ext = libbpf_reallocarray(ext, obj->nr_extern + 1, sizeof(*ext)); |
---|
| 3119 | + if (!ext) |
---|
| 3120 | + return -ENOMEM; |
---|
| 3121 | + obj->externs = ext; |
---|
| 3122 | + ext = &ext[obj->nr_extern]; |
---|
| 3123 | + memset(ext, 0, sizeof(*ext)); |
---|
| 3124 | + obj->nr_extern++; |
---|
| 3125 | + |
---|
| 3126 | + ext->btf_id = find_extern_btf_id(obj->btf, ext_name); |
---|
| 3127 | + if (ext->btf_id <= 0) { |
---|
| 3128 | + pr_warn("failed to find BTF for extern '%s': %d\n", |
---|
| 3129 | + ext_name, ext->btf_id); |
---|
| 3130 | + return ext->btf_id; |
---|
| 3131 | + } |
---|
| 3132 | + t = btf__type_by_id(obj->btf, ext->btf_id); |
---|
| 3133 | + ext->name = btf__name_by_offset(obj->btf, t->name_off); |
---|
| 3134 | + ext->sym_idx = i; |
---|
| 3135 | + ext->is_weak = GELF_ST_BIND(sym.st_info) == STB_WEAK; |
---|
| 3136 | + |
---|
| 3137 | + ext->sec_btf_id = find_extern_sec_btf_id(obj->btf, ext->btf_id); |
---|
| 3138 | + if (ext->sec_btf_id <= 0) { |
---|
| 3139 | + pr_warn("failed to find BTF for extern '%s' [%d] section: %d\n", |
---|
| 3140 | + ext_name, ext->btf_id, ext->sec_btf_id); |
---|
| 3141 | + return ext->sec_btf_id; |
---|
| 3142 | + } |
---|
| 3143 | + sec = (void *)btf__type_by_id(obj->btf, ext->sec_btf_id); |
---|
| 3144 | + sec_name = btf__name_by_offset(obj->btf, sec->name_off); |
---|
| 3145 | + |
---|
| 3146 | + if (strcmp(sec_name, KCONFIG_SEC) == 0) { |
---|
| 3147 | + kcfg_sec = sec; |
---|
| 3148 | + ext->type = EXT_KCFG; |
---|
| 3149 | + ext->kcfg.sz = btf__resolve_size(obj->btf, t->type); |
---|
| 3150 | + if (ext->kcfg.sz <= 0) { |
---|
| 3151 | + pr_warn("failed to resolve size of extern (kcfg) '%s': %d\n", |
---|
| 3152 | + ext_name, ext->kcfg.sz); |
---|
| 3153 | + return ext->kcfg.sz; |
---|
| 3154 | + } |
---|
| 3155 | + ext->kcfg.align = btf__align_of(obj->btf, t->type); |
---|
| 3156 | + if (ext->kcfg.align <= 0) { |
---|
| 3157 | + pr_warn("failed to determine alignment of extern (kcfg) '%s': %d\n", |
---|
| 3158 | + ext_name, ext->kcfg.align); |
---|
| 3159 | + return -EINVAL; |
---|
| 3160 | + } |
---|
| 3161 | + ext->kcfg.type = find_kcfg_type(obj->btf, t->type, |
---|
| 3162 | + &ext->kcfg.is_signed); |
---|
| 3163 | + if (ext->kcfg.type == KCFG_UNKNOWN) { |
---|
| 3164 | + pr_warn("extern (kcfg) '%s' type is unsupported\n", ext_name); |
---|
| 3165 | + return -ENOTSUP; |
---|
| 3166 | + } |
---|
| 3167 | + } else if (strcmp(sec_name, KSYMS_SEC) == 0) { |
---|
| 3168 | + ksym_sec = sec; |
---|
| 3169 | + ext->type = EXT_KSYM; |
---|
| 3170 | + skip_mods_and_typedefs(obj->btf, t->type, |
---|
| 3171 | + &ext->ksym.type_id); |
---|
| 3172 | + } else { |
---|
| 3173 | + pr_warn("unrecognized extern section '%s'\n", sec_name); |
---|
| 3174 | + return -ENOTSUP; |
---|
| 3175 | + } |
---|
| 3176 | + } |
---|
| 3177 | + pr_debug("collected %d externs total\n", obj->nr_extern); |
---|
| 3178 | + |
---|
| 3179 | + if (!obj->nr_extern) |
---|
| 3180 | + return 0; |
---|
| 3181 | + |
---|
| 3182 | + /* sort externs by type, for kcfg ones also by (align, size, name) */ |
---|
| 3183 | + qsort(obj->externs, obj->nr_extern, sizeof(*ext), cmp_externs); |
---|
| 3184 | + |
---|
| 3185 | + /* for .ksyms section, we need to turn all externs into allocated |
---|
| 3186 | + * variables in BTF to pass kernel verification; we do this by |
---|
| 3187 | + * pretending that each extern is a 8-byte variable |
---|
| 3188 | + */ |
---|
| 3189 | + if (ksym_sec) { |
---|
| 3190 | + /* find existing 4-byte integer type in BTF to use for fake |
---|
| 3191 | + * extern variables in DATASEC |
---|
| 3192 | + */ |
---|
| 3193 | + int int_btf_id = find_int_btf_id(obj->btf); |
---|
| 3194 | + |
---|
| 3195 | + for (i = 0; i < obj->nr_extern; i++) { |
---|
| 3196 | + ext = &obj->externs[i]; |
---|
| 3197 | + if (ext->type != EXT_KSYM) |
---|
| 3198 | + continue; |
---|
| 3199 | + pr_debug("extern (ksym) #%d: symbol %d, name %s\n", |
---|
| 3200 | + i, ext->sym_idx, ext->name); |
---|
| 3201 | + } |
---|
| 3202 | + |
---|
| 3203 | + sec = ksym_sec; |
---|
| 3204 | + n = btf_vlen(sec); |
---|
| 3205 | + for (i = 0, off = 0; i < n; i++, off += sizeof(int)) { |
---|
| 3206 | + struct btf_var_secinfo *vs = btf_var_secinfos(sec) + i; |
---|
| 3207 | + struct btf_type *vt; |
---|
| 3208 | + |
---|
| 3209 | + vt = (void *)btf__type_by_id(obj->btf, vs->type); |
---|
| 3210 | + ext_name = btf__name_by_offset(obj->btf, vt->name_off); |
---|
| 3211 | + ext = find_extern_by_name(obj, ext_name); |
---|
| 3212 | + if (!ext) { |
---|
| 3213 | + pr_warn("failed to find extern definition for BTF var '%s'\n", |
---|
| 3214 | + ext_name); |
---|
| 3215 | + return -ESRCH; |
---|
| 3216 | + } |
---|
| 3217 | + btf_var(vt)->linkage = BTF_VAR_GLOBAL_ALLOCATED; |
---|
| 3218 | + vt->type = int_btf_id; |
---|
| 3219 | + vs->offset = off; |
---|
| 3220 | + vs->size = sizeof(int); |
---|
| 3221 | + } |
---|
| 3222 | + sec->size = off; |
---|
| 3223 | + } |
---|
| 3224 | + |
---|
| 3225 | + if (kcfg_sec) { |
---|
| 3226 | + sec = kcfg_sec; |
---|
| 3227 | + /* for kcfg externs calculate their offsets within a .kconfig map */ |
---|
| 3228 | + off = 0; |
---|
| 3229 | + for (i = 0; i < obj->nr_extern; i++) { |
---|
| 3230 | + ext = &obj->externs[i]; |
---|
| 3231 | + if (ext->type != EXT_KCFG) |
---|
| 3232 | + continue; |
---|
| 3233 | + |
---|
| 3234 | + ext->kcfg.data_off = roundup(off, ext->kcfg.align); |
---|
| 3235 | + off = ext->kcfg.data_off + ext->kcfg.sz; |
---|
| 3236 | + pr_debug("extern (kcfg) #%d: symbol %d, off %u, name %s\n", |
---|
| 3237 | + i, ext->sym_idx, ext->kcfg.data_off, ext->name); |
---|
| 3238 | + } |
---|
| 3239 | + sec->size = off; |
---|
| 3240 | + n = btf_vlen(sec); |
---|
| 3241 | + for (i = 0; i < n; i++) { |
---|
| 3242 | + struct btf_var_secinfo *vs = btf_var_secinfos(sec) + i; |
---|
| 3243 | + |
---|
| 3244 | + t = btf__type_by_id(obj->btf, vs->type); |
---|
| 3245 | + ext_name = btf__name_by_offset(obj->btf, t->name_off); |
---|
| 3246 | + ext = find_extern_by_name(obj, ext_name); |
---|
| 3247 | + if (!ext) { |
---|
| 3248 | + pr_warn("failed to find extern definition for BTF var '%s'\n", |
---|
| 3249 | + ext_name); |
---|
| 3250 | + return -ESRCH; |
---|
| 3251 | + } |
---|
| 3252 | + btf_var(t)->linkage = BTF_VAR_GLOBAL_ALLOCATED; |
---|
| 3253 | + vs->offset = ext->kcfg.data_off; |
---|
| 3254 | + } |
---|
| 3255 | + } |
---|
| 3256 | + return 0; |
---|
| 3257 | +} |
---|
| 3258 | + |
---|
882 | 3259 | struct bpf_program * |
---|
883 | | -bpf_object__find_program_by_title(struct bpf_object *obj, const char *title) |
---|
| 3260 | +bpf_object__find_program_by_title(const struct bpf_object *obj, |
---|
| 3261 | + const char *title) |
---|
884 | 3262 | { |
---|
885 | 3263 | struct bpf_program *pos; |
---|
886 | 3264 | |
---|
887 | 3265 | bpf_object__for_each_program(pos, obj) { |
---|
888 | | - if (pos->section_name && !strcmp(pos->section_name, title)) |
---|
| 3266 | + if (pos->sec_name && !strcmp(pos->sec_name, title)) |
---|
889 | 3267 | return pos; |
---|
890 | 3268 | } |
---|
891 | 3269 | return NULL; |
---|
892 | 3270 | } |
---|
893 | 3271 | |
---|
| 3272 | +static bool prog_is_subprog(const struct bpf_object *obj, |
---|
| 3273 | + const struct bpf_program *prog) |
---|
| 3274 | +{ |
---|
| 3275 | + /* For legacy reasons, libbpf supports an entry-point BPF programs |
---|
| 3276 | + * without SEC() attribute, i.e., those in the .text section. But if |
---|
| 3277 | + * there are 2 or more such programs in the .text section, they all |
---|
| 3278 | + * must be subprograms called from entry-point BPF programs in |
---|
| 3279 | + * designated SEC()'tions, otherwise there is no way to distinguish |
---|
| 3280 | + * which of those programs should be loaded vs which are a subprogram. |
---|
| 3281 | + * Similarly, if there is a function/program in .text and at least one |
---|
| 3282 | + * other BPF program with custom SEC() attribute, then we just assume |
---|
| 3283 | + * .text programs are subprograms (even if they are not called from |
---|
| 3284 | + * other programs), because libbpf never explicitly supported mixing |
---|
| 3285 | + * SEC()-designated BPF programs and .text entry-point BPF programs. |
---|
| 3286 | + */ |
---|
| 3287 | + return prog->sec_idx == obj->efile.text_shndx && obj->nr_programs > 1; |
---|
| 3288 | +} |
---|
| 3289 | + |
---|
| 3290 | +struct bpf_program * |
---|
| 3291 | +bpf_object__find_program_by_name(const struct bpf_object *obj, |
---|
| 3292 | + const char *name) |
---|
| 3293 | +{ |
---|
| 3294 | + struct bpf_program *prog; |
---|
| 3295 | + |
---|
| 3296 | + bpf_object__for_each_program(prog, obj) { |
---|
| 3297 | + if (prog_is_subprog(obj, prog)) |
---|
| 3298 | + continue; |
---|
| 3299 | + if (!strcmp(prog->name, name)) |
---|
| 3300 | + return prog; |
---|
| 3301 | + } |
---|
| 3302 | + return NULL; |
---|
| 3303 | +} |
---|
| 3304 | + |
---|
| 3305 | +static bool bpf_object__shndx_is_data(const struct bpf_object *obj, |
---|
| 3306 | + int shndx) |
---|
| 3307 | +{ |
---|
| 3308 | + return shndx == obj->efile.data_shndx || |
---|
| 3309 | + shndx == obj->efile.bss_shndx || |
---|
| 3310 | + shndx == obj->efile.rodata_shndx; |
---|
| 3311 | +} |
---|
| 3312 | + |
---|
| 3313 | +static bool bpf_object__shndx_is_maps(const struct bpf_object *obj, |
---|
| 3314 | + int shndx) |
---|
| 3315 | +{ |
---|
| 3316 | + return shndx == obj->efile.maps_shndx || |
---|
| 3317 | + shndx == obj->efile.btf_maps_shndx; |
---|
| 3318 | +} |
---|
| 3319 | + |
---|
| 3320 | +static enum libbpf_map_type |
---|
| 3321 | +bpf_object__section_to_libbpf_map_type(const struct bpf_object *obj, int shndx) |
---|
| 3322 | +{ |
---|
| 3323 | + if (shndx == obj->efile.data_shndx) |
---|
| 3324 | + return LIBBPF_MAP_DATA; |
---|
| 3325 | + else if (shndx == obj->efile.bss_shndx) |
---|
| 3326 | + return LIBBPF_MAP_BSS; |
---|
| 3327 | + else if (shndx == obj->efile.rodata_shndx) |
---|
| 3328 | + return LIBBPF_MAP_RODATA; |
---|
| 3329 | + else if (shndx == obj->efile.symbols_shndx) |
---|
| 3330 | + return LIBBPF_MAP_KCONFIG; |
---|
| 3331 | + else |
---|
| 3332 | + return LIBBPF_MAP_UNSPEC; |
---|
| 3333 | +} |
---|
| 3334 | + |
---|
| 3335 | +static int bpf_program__record_reloc(struct bpf_program *prog, |
---|
| 3336 | + struct reloc_desc *reloc_desc, |
---|
| 3337 | + __u32 insn_idx, const char *sym_name, |
---|
| 3338 | + const GElf_Sym *sym, const GElf_Rel *rel) |
---|
| 3339 | +{ |
---|
| 3340 | + struct bpf_insn *insn = &prog->insns[insn_idx]; |
---|
| 3341 | + size_t map_idx, nr_maps = prog->obj->nr_maps; |
---|
| 3342 | + struct bpf_object *obj = prog->obj; |
---|
| 3343 | + __u32 shdr_idx = sym->st_shndx; |
---|
| 3344 | + enum libbpf_map_type type; |
---|
| 3345 | + const char *sym_sec_name; |
---|
| 3346 | + struct bpf_map *map; |
---|
| 3347 | + |
---|
| 3348 | + reloc_desc->processed = false; |
---|
| 3349 | + |
---|
| 3350 | + /* sub-program call relocation */ |
---|
| 3351 | + if (insn->code == (BPF_JMP | BPF_CALL)) { |
---|
| 3352 | + if (insn->src_reg != BPF_PSEUDO_CALL) { |
---|
| 3353 | + pr_warn("prog '%s': incorrect bpf_call opcode\n", prog->name); |
---|
| 3354 | + return -LIBBPF_ERRNO__RELOC; |
---|
| 3355 | + } |
---|
| 3356 | + /* text_shndx can be 0, if no default "main" program exists */ |
---|
| 3357 | + if (!shdr_idx || shdr_idx != obj->efile.text_shndx) { |
---|
| 3358 | + sym_sec_name = elf_sec_name(obj, elf_sec_by_idx(obj, shdr_idx)); |
---|
| 3359 | + pr_warn("prog '%s': bad call relo against '%s' in section '%s'\n", |
---|
| 3360 | + prog->name, sym_name, sym_sec_name); |
---|
| 3361 | + return -LIBBPF_ERRNO__RELOC; |
---|
| 3362 | + } |
---|
| 3363 | + if (sym->st_value % BPF_INSN_SZ) { |
---|
| 3364 | + pr_warn("prog '%s': bad call relo against '%s' at offset %zu\n", |
---|
| 3365 | + prog->name, sym_name, (size_t)sym->st_value); |
---|
| 3366 | + return -LIBBPF_ERRNO__RELOC; |
---|
| 3367 | + } |
---|
| 3368 | + reloc_desc->type = RELO_CALL; |
---|
| 3369 | + reloc_desc->insn_idx = insn_idx; |
---|
| 3370 | + reloc_desc->sym_off = sym->st_value; |
---|
| 3371 | + return 0; |
---|
| 3372 | + } |
---|
| 3373 | + |
---|
| 3374 | + if (insn->code != (BPF_LD | BPF_IMM | BPF_DW)) { |
---|
| 3375 | + pr_warn("prog '%s': invalid relo against '%s' for insns[%d].code 0x%x\n", |
---|
| 3376 | + prog->name, sym_name, insn_idx, insn->code); |
---|
| 3377 | + return -LIBBPF_ERRNO__RELOC; |
---|
| 3378 | + } |
---|
| 3379 | + |
---|
| 3380 | + if (sym_is_extern(sym)) { |
---|
| 3381 | + int sym_idx = GELF_R_SYM(rel->r_info); |
---|
| 3382 | + int i, n = obj->nr_extern; |
---|
| 3383 | + struct extern_desc *ext; |
---|
| 3384 | + |
---|
| 3385 | + for (i = 0; i < n; i++) { |
---|
| 3386 | + ext = &obj->externs[i]; |
---|
| 3387 | + if (ext->sym_idx == sym_idx) |
---|
| 3388 | + break; |
---|
| 3389 | + } |
---|
| 3390 | + if (i >= n) { |
---|
| 3391 | + pr_warn("prog '%s': extern relo failed to find extern for '%s' (%d)\n", |
---|
| 3392 | + prog->name, sym_name, sym_idx); |
---|
| 3393 | + return -LIBBPF_ERRNO__RELOC; |
---|
| 3394 | + } |
---|
| 3395 | + pr_debug("prog '%s': found extern #%d '%s' (sym %d) for insn #%u\n", |
---|
| 3396 | + prog->name, i, ext->name, ext->sym_idx, insn_idx); |
---|
| 3397 | + reloc_desc->type = RELO_EXTERN; |
---|
| 3398 | + reloc_desc->insn_idx = insn_idx; |
---|
| 3399 | + reloc_desc->sym_off = i; /* sym_off stores extern index */ |
---|
| 3400 | + return 0; |
---|
| 3401 | + } |
---|
| 3402 | + |
---|
| 3403 | + if (!shdr_idx || shdr_idx >= SHN_LORESERVE) { |
---|
| 3404 | + pr_warn("prog '%s': invalid relo against '%s' in special section 0x%x; forgot to initialize global var?..\n", |
---|
| 3405 | + prog->name, sym_name, shdr_idx); |
---|
| 3406 | + return -LIBBPF_ERRNO__RELOC; |
---|
| 3407 | + } |
---|
| 3408 | + |
---|
| 3409 | + type = bpf_object__section_to_libbpf_map_type(obj, shdr_idx); |
---|
| 3410 | + sym_sec_name = elf_sec_name(obj, elf_sec_by_idx(obj, shdr_idx)); |
---|
| 3411 | + |
---|
| 3412 | + /* generic map reference relocation */ |
---|
| 3413 | + if (type == LIBBPF_MAP_UNSPEC) { |
---|
| 3414 | + if (!bpf_object__shndx_is_maps(obj, shdr_idx)) { |
---|
| 3415 | + pr_warn("prog '%s': bad map relo against '%s' in section '%s'\n", |
---|
| 3416 | + prog->name, sym_name, sym_sec_name); |
---|
| 3417 | + return -LIBBPF_ERRNO__RELOC; |
---|
| 3418 | + } |
---|
| 3419 | + for (map_idx = 0; map_idx < nr_maps; map_idx++) { |
---|
| 3420 | + map = &obj->maps[map_idx]; |
---|
| 3421 | + if (map->libbpf_type != type || |
---|
| 3422 | + map->sec_idx != sym->st_shndx || |
---|
| 3423 | + map->sec_offset != sym->st_value) |
---|
| 3424 | + continue; |
---|
| 3425 | + pr_debug("prog '%s': found map %zd (%s, sec %d, off %zu) for insn #%u\n", |
---|
| 3426 | + prog->name, map_idx, map->name, map->sec_idx, |
---|
| 3427 | + map->sec_offset, insn_idx); |
---|
| 3428 | + break; |
---|
| 3429 | + } |
---|
| 3430 | + if (map_idx >= nr_maps) { |
---|
| 3431 | + pr_warn("prog '%s': map relo failed to find map for section '%s', off %zu\n", |
---|
| 3432 | + prog->name, sym_sec_name, (size_t)sym->st_value); |
---|
| 3433 | + return -LIBBPF_ERRNO__RELOC; |
---|
| 3434 | + } |
---|
| 3435 | + reloc_desc->type = RELO_LD64; |
---|
| 3436 | + reloc_desc->insn_idx = insn_idx; |
---|
| 3437 | + reloc_desc->map_idx = map_idx; |
---|
| 3438 | + reloc_desc->sym_off = 0; /* sym->st_value determines map_idx */ |
---|
| 3439 | + return 0; |
---|
| 3440 | + } |
---|
| 3441 | + |
---|
| 3442 | + /* global data map relocation */ |
---|
| 3443 | + if (!bpf_object__shndx_is_data(obj, shdr_idx)) { |
---|
| 3444 | + pr_warn("prog '%s': bad data relo against section '%s'\n", |
---|
| 3445 | + prog->name, sym_sec_name); |
---|
| 3446 | + return -LIBBPF_ERRNO__RELOC; |
---|
| 3447 | + } |
---|
| 3448 | + for (map_idx = 0; map_idx < nr_maps; map_idx++) { |
---|
| 3449 | + map = &obj->maps[map_idx]; |
---|
| 3450 | + if (map->libbpf_type != type) |
---|
| 3451 | + continue; |
---|
| 3452 | + pr_debug("prog '%s': found data map %zd (%s, sec %d, off %zu) for insn %u\n", |
---|
| 3453 | + prog->name, map_idx, map->name, map->sec_idx, |
---|
| 3454 | + map->sec_offset, insn_idx); |
---|
| 3455 | + break; |
---|
| 3456 | + } |
---|
| 3457 | + if (map_idx >= nr_maps) { |
---|
| 3458 | + pr_warn("prog '%s': data relo failed to find map for section '%s'\n", |
---|
| 3459 | + prog->name, sym_sec_name); |
---|
| 3460 | + return -LIBBPF_ERRNO__RELOC; |
---|
| 3461 | + } |
---|
| 3462 | + |
---|
| 3463 | + reloc_desc->type = RELO_DATA; |
---|
| 3464 | + reloc_desc->insn_idx = insn_idx; |
---|
| 3465 | + reloc_desc->map_idx = map_idx; |
---|
| 3466 | + reloc_desc->sym_off = sym->st_value; |
---|
| 3467 | + return 0; |
---|
| 3468 | +} |
---|
| 3469 | + |
---|
| 3470 | +static bool prog_contains_insn(const struct bpf_program *prog, size_t insn_idx) |
---|
| 3471 | +{ |
---|
| 3472 | + return insn_idx >= prog->sec_insn_off && |
---|
| 3473 | + insn_idx < prog->sec_insn_off + prog->sec_insn_cnt; |
---|
| 3474 | +} |
---|
| 3475 | + |
---|
| 3476 | +static struct bpf_program *find_prog_by_sec_insn(const struct bpf_object *obj, |
---|
| 3477 | + size_t sec_idx, size_t insn_idx) |
---|
| 3478 | +{ |
---|
| 3479 | + int l = 0, r = obj->nr_programs - 1, m; |
---|
| 3480 | + struct bpf_program *prog; |
---|
| 3481 | + |
---|
| 3482 | + if (!obj->nr_programs) |
---|
| 3483 | + return NULL; |
---|
| 3484 | + |
---|
| 3485 | + while (l < r) { |
---|
| 3486 | + m = l + (r - l + 1) / 2; |
---|
| 3487 | + prog = &obj->programs[m]; |
---|
| 3488 | + |
---|
| 3489 | + if (prog->sec_idx < sec_idx || |
---|
| 3490 | + (prog->sec_idx == sec_idx && prog->sec_insn_off <= insn_idx)) |
---|
| 3491 | + l = m; |
---|
| 3492 | + else |
---|
| 3493 | + r = m - 1; |
---|
| 3494 | + } |
---|
| 3495 | + /* matching program could be at index l, but it still might be the |
---|
| 3496 | + * wrong one, so we need to double check conditions for the last time |
---|
| 3497 | + */ |
---|
| 3498 | + prog = &obj->programs[l]; |
---|
| 3499 | + if (prog->sec_idx == sec_idx && prog_contains_insn(prog, insn_idx)) |
---|
| 3500 | + return prog; |
---|
| 3501 | + return NULL; |
---|
| 3502 | +} |
---|
| 3503 | + |
---|
894 | 3504 | static int |
---|
895 | | -bpf_program__collect_reloc(struct bpf_program *prog, GElf_Shdr *shdr, |
---|
896 | | - Elf_Data *data, struct bpf_object *obj) |
---|
| 3505 | +bpf_object__collect_prog_relos(struct bpf_object *obj, GElf_Shdr *shdr, Elf_Data *data) |
---|
897 | 3506 | { |
---|
898 | 3507 | Elf_Data *symbols = obj->efile.symbols; |
---|
899 | | - int text_shndx = obj->efile.text_shndx; |
---|
900 | | - int maps_shndx = obj->efile.maps_shndx; |
---|
901 | | - struct bpf_map *maps = obj->maps; |
---|
902 | | - size_t nr_maps = obj->nr_maps; |
---|
903 | | - int i, nrels; |
---|
| 3508 | + const char *relo_sec_name, *sec_name; |
---|
| 3509 | + size_t sec_idx = shdr->sh_info; |
---|
| 3510 | + struct bpf_program *prog; |
---|
| 3511 | + struct reloc_desc *relos; |
---|
| 3512 | + int err, i, nrels; |
---|
| 3513 | + const char *sym_name; |
---|
| 3514 | + __u32 insn_idx; |
---|
| 3515 | + GElf_Sym sym; |
---|
| 3516 | + GElf_Rel rel; |
---|
904 | 3517 | |
---|
905 | | - pr_debug("collecting relocating info for: '%s'\n", |
---|
906 | | - prog->section_name); |
---|
| 3518 | + relo_sec_name = elf_sec_str(obj, shdr->sh_name); |
---|
| 3519 | + sec_name = elf_sec_name(obj, elf_sec_by_idx(obj, sec_idx)); |
---|
| 3520 | + if (!relo_sec_name || !sec_name) |
---|
| 3521 | + return -EINVAL; |
---|
| 3522 | + |
---|
| 3523 | + pr_debug("sec '%s': collecting relocation for section(%zu) '%s'\n", |
---|
| 3524 | + relo_sec_name, sec_idx, sec_name); |
---|
907 | 3525 | nrels = shdr->sh_size / shdr->sh_entsize; |
---|
908 | 3526 | |
---|
909 | | - prog->reloc_desc = malloc(sizeof(*prog->reloc_desc) * nrels); |
---|
910 | | - if (!prog->reloc_desc) { |
---|
911 | | - pr_warning("failed to alloc memory in relocation\n"); |
---|
912 | | - return -ENOMEM; |
---|
913 | | - } |
---|
914 | | - prog->nr_reloc = nrels; |
---|
915 | | - |
---|
916 | 3527 | for (i = 0; i < nrels; i++) { |
---|
917 | | - GElf_Sym sym; |
---|
918 | | - GElf_Rel rel; |
---|
919 | | - unsigned int insn_idx; |
---|
920 | | - struct bpf_insn *insns = prog->insns; |
---|
921 | | - size_t map_idx; |
---|
922 | | - |
---|
923 | 3528 | if (!gelf_getrel(data, i, &rel)) { |
---|
924 | | - pr_warning("relocation: failed to get %d reloc\n", i); |
---|
| 3529 | + pr_warn("sec '%s': failed to get relo #%d\n", relo_sec_name, i); |
---|
| 3530 | + return -LIBBPF_ERRNO__FORMAT; |
---|
| 3531 | + } |
---|
| 3532 | + if (!gelf_getsym(symbols, GELF_R_SYM(rel.r_info), &sym)) { |
---|
| 3533 | + pr_warn("sec '%s': symbol 0x%zx not found for relo #%d\n", |
---|
| 3534 | + relo_sec_name, (size_t)GELF_R_SYM(rel.r_info), i); |
---|
| 3535 | + return -LIBBPF_ERRNO__FORMAT; |
---|
| 3536 | + } |
---|
| 3537 | + if (rel.r_offset % BPF_INSN_SZ) { |
---|
| 3538 | + pr_warn("sec '%s': invalid offset 0x%zx for relo #%d\n", |
---|
| 3539 | + relo_sec_name, (size_t)GELF_R_SYM(rel.r_info), i); |
---|
925 | 3540 | return -LIBBPF_ERRNO__FORMAT; |
---|
926 | 3541 | } |
---|
927 | 3542 | |
---|
928 | | - if (!gelf_getsym(symbols, |
---|
929 | | - GELF_R_SYM(rel.r_info), |
---|
930 | | - &sym)) { |
---|
931 | | - pr_warning("relocation: symbol %"PRIx64" not found\n", |
---|
932 | | - GELF_R_SYM(rel.r_info)); |
---|
933 | | - return -LIBBPF_ERRNO__FORMAT; |
---|
934 | | - } |
---|
935 | | - pr_debug("relo for %lld value %lld name %d\n", |
---|
936 | | - (long long) (rel.r_info >> 32), |
---|
937 | | - (long long) sym.st_value, sym.st_name); |
---|
| 3543 | + insn_idx = rel.r_offset / BPF_INSN_SZ; |
---|
| 3544 | + /* relocations against static functions are recorded as |
---|
| 3545 | + * relocations against the section that contains a function; |
---|
| 3546 | + * in such case, symbol will be STT_SECTION and sym.st_name |
---|
| 3547 | + * will point to empty string (0), so fetch section name |
---|
| 3548 | + * instead |
---|
| 3549 | + */ |
---|
| 3550 | + if (GELF_ST_TYPE(sym.st_info) == STT_SECTION && sym.st_name == 0) |
---|
| 3551 | + sym_name = elf_sec_name(obj, elf_sec_by_idx(obj, sym.st_shndx)); |
---|
| 3552 | + else |
---|
| 3553 | + sym_name = elf_sym_str(obj, sym.st_name); |
---|
| 3554 | + sym_name = sym_name ?: "<?"; |
---|
938 | 3555 | |
---|
939 | | - if (sym.st_shndx != maps_shndx && sym.st_shndx != text_shndx) { |
---|
940 | | - pr_warning("Program '%s' contains non-map related relo data pointing to section %u\n", |
---|
941 | | - prog->section_name, sym.st_shndx); |
---|
| 3556 | + pr_debug("sec '%s': relo #%d: insn #%u against '%s'\n", |
---|
| 3557 | + relo_sec_name, i, insn_idx, sym_name); |
---|
| 3558 | + |
---|
| 3559 | + prog = find_prog_by_sec_insn(obj, sec_idx, insn_idx); |
---|
| 3560 | + if (!prog) { |
---|
| 3561 | + pr_warn("sec '%s': relo #%d: program not found in section '%s' for insn #%u\n", |
---|
| 3562 | + relo_sec_name, i, sec_name, insn_idx); |
---|
942 | 3563 | return -LIBBPF_ERRNO__RELOC; |
---|
943 | 3564 | } |
---|
944 | 3565 | |
---|
945 | | - insn_idx = rel.r_offset / sizeof(struct bpf_insn); |
---|
946 | | - pr_debug("relocation: insn_idx=%u\n", insn_idx); |
---|
| 3566 | + relos = libbpf_reallocarray(prog->reloc_desc, |
---|
| 3567 | + prog->nr_reloc + 1, sizeof(*relos)); |
---|
| 3568 | + if (!relos) |
---|
| 3569 | + return -ENOMEM; |
---|
| 3570 | + prog->reloc_desc = relos; |
---|
947 | 3571 | |
---|
948 | | - if (insns[insn_idx].code == (BPF_JMP | BPF_CALL)) { |
---|
949 | | - if (insns[insn_idx].src_reg != BPF_PSEUDO_CALL) { |
---|
950 | | - pr_warning("incorrect bpf_call opcode\n"); |
---|
951 | | - return -LIBBPF_ERRNO__RELOC; |
---|
952 | | - } |
---|
953 | | - prog->reloc_desc[i].type = RELO_CALL; |
---|
954 | | - prog->reloc_desc[i].insn_idx = insn_idx; |
---|
955 | | - prog->reloc_desc[i].text_off = sym.st_value; |
---|
956 | | - obj->has_pseudo_calls = true; |
---|
957 | | - continue; |
---|
958 | | - } |
---|
| 3572 | + /* adjust insn_idx to local BPF program frame of reference */ |
---|
| 3573 | + insn_idx -= prog->sec_insn_off; |
---|
| 3574 | + err = bpf_program__record_reloc(prog, &relos[prog->nr_reloc], |
---|
| 3575 | + insn_idx, sym_name, &sym, &rel); |
---|
| 3576 | + if (err) |
---|
| 3577 | + return err; |
---|
959 | 3578 | |
---|
960 | | - if (insns[insn_idx].code != (BPF_LD | BPF_IMM | BPF_DW)) { |
---|
961 | | - pr_warning("bpf: relocation: invalid relo for insns[%d].code 0x%x\n", |
---|
962 | | - insn_idx, insns[insn_idx].code); |
---|
963 | | - return -LIBBPF_ERRNO__RELOC; |
---|
964 | | - } |
---|
965 | | - |
---|
966 | | - /* TODO: 'maps' is sorted. We can use bsearch to make it faster. */ |
---|
967 | | - for (map_idx = 0; map_idx < nr_maps; map_idx++) { |
---|
968 | | - if (maps[map_idx].offset == sym.st_value) { |
---|
969 | | - pr_debug("relocation: find map %zd (%s) for insn %u\n", |
---|
970 | | - map_idx, maps[map_idx].name, insn_idx); |
---|
971 | | - break; |
---|
972 | | - } |
---|
973 | | - } |
---|
974 | | - |
---|
975 | | - if (map_idx >= nr_maps) { |
---|
976 | | - pr_warning("bpf relocation: map_idx %d large than %d\n", |
---|
977 | | - (int)map_idx, (int)nr_maps - 1); |
---|
978 | | - return -LIBBPF_ERRNO__RELOC; |
---|
979 | | - } |
---|
980 | | - |
---|
981 | | - prog->reloc_desc[i].type = RELO_LD64; |
---|
982 | | - prog->reloc_desc[i].insn_idx = insn_idx; |
---|
983 | | - prog->reloc_desc[i].map_idx = map_idx; |
---|
| 3579 | + prog->nr_reloc++; |
---|
984 | 3580 | } |
---|
985 | 3581 | return 0; |
---|
986 | 3582 | } |
---|
987 | 3583 | |
---|
988 | | -static int bpf_map_find_btf_info(struct bpf_map *map, const struct btf *btf) |
---|
| 3584 | +static int bpf_map_find_btf_info(struct bpf_object *obj, struct bpf_map *map) |
---|
989 | 3585 | { |
---|
990 | | - const struct btf_type *container_type; |
---|
991 | | - const struct btf_member *key, *value; |
---|
992 | 3586 | struct bpf_map_def *def = &map->def; |
---|
993 | | - const size_t max_name = 256; |
---|
994 | | - char container_name[max_name]; |
---|
995 | | - __s64 key_size, value_size; |
---|
996 | | - __s32 container_id; |
---|
| 3587 | + __u32 key_type_id = 0, value_type_id = 0; |
---|
| 3588 | + int ret; |
---|
997 | 3589 | |
---|
998 | | - if (snprintf(container_name, max_name, "____btf_map_%s", map->name) == |
---|
999 | | - max_name) { |
---|
1000 | | - pr_warning("map:%s length of '____btf_map_%s' is too long\n", |
---|
1001 | | - map->name, map->name); |
---|
1002 | | - return -EINVAL; |
---|
| 3590 | + /* if it's BTF-defined map, we don't need to search for type IDs. |
---|
| 3591 | + * For struct_ops map, it does not need btf_key_type_id and |
---|
| 3592 | + * btf_value_type_id. |
---|
| 3593 | + */ |
---|
| 3594 | + if (map->sec_idx == obj->efile.btf_maps_shndx || |
---|
| 3595 | + bpf_map__is_struct_ops(map)) |
---|
| 3596 | + return 0; |
---|
| 3597 | + |
---|
| 3598 | + if (!bpf_map__is_internal(map)) { |
---|
| 3599 | + ret = btf__get_map_kv_tids(obj->btf, map->name, def->key_size, |
---|
| 3600 | + def->value_size, &key_type_id, |
---|
| 3601 | + &value_type_id); |
---|
| 3602 | + } else { |
---|
| 3603 | + /* |
---|
| 3604 | + * LLVM annotates global data differently in BTF, that is, |
---|
| 3605 | + * only as '.data', '.bss' or '.rodata'. |
---|
| 3606 | + */ |
---|
| 3607 | + ret = btf__find_by_name(obj->btf, |
---|
| 3608 | + libbpf_type_to_btf_name[map->libbpf_type]); |
---|
| 3609 | + } |
---|
| 3610 | + if (ret < 0) |
---|
| 3611 | + return ret; |
---|
| 3612 | + |
---|
| 3613 | + map->btf_key_type_id = key_type_id; |
---|
| 3614 | + map->btf_value_type_id = bpf_map__is_internal(map) ? |
---|
| 3615 | + ret : value_type_id; |
---|
| 3616 | + return 0; |
---|
| 3617 | +} |
---|
| 3618 | + |
---|
| 3619 | +static int bpf_get_map_info_from_fdinfo(int fd, struct bpf_map_info *info) |
---|
| 3620 | +{ |
---|
| 3621 | + char file[PATH_MAX], buff[4096]; |
---|
| 3622 | + FILE *fp; |
---|
| 3623 | + __u32 val; |
---|
| 3624 | + int err; |
---|
| 3625 | + |
---|
| 3626 | + snprintf(file, sizeof(file), "/proc/%d/fdinfo/%d", getpid(), fd); |
---|
| 3627 | + memset(info, 0, sizeof(*info)); |
---|
| 3628 | + |
---|
| 3629 | + fp = fopen(file, "r"); |
---|
| 3630 | + if (!fp) { |
---|
| 3631 | + err = -errno; |
---|
| 3632 | + pr_warn("failed to open %s: %d. No procfs support?\n", file, |
---|
| 3633 | + err); |
---|
| 3634 | + return err; |
---|
1003 | 3635 | } |
---|
1004 | 3636 | |
---|
1005 | | - container_id = btf__find_by_name(btf, container_name); |
---|
1006 | | - if (container_id < 0) { |
---|
1007 | | - pr_debug("map:%s container_name:%s cannot be found in BTF. Missing BPF_ANNOTATE_KV_PAIR?\n", |
---|
1008 | | - map->name, container_name); |
---|
1009 | | - return container_id; |
---|
| 3637 | + while (fgets(buff, sizeof(buff), fp)) { |
---|
| 3638 | + if (sscanf(buff, "map_type:\t%u", &val) == 1) |
---|
| 3639 | + info->type = val; |
---|
| 3640 | + else if (sscanf(buff, "key_size:\t%u", &val) == 1) |
---|
| 3641 | + info->key_size = val; |
---|
| 3642 | + else if (sscanf(buff, "value_size:\t%u", &val) == 1) |
---|
| 3643 | + info->value_size = val; |
---|
| 3644 | + else if (sscanf(buff, "max_entries:\t%u", &val) == 1) |
---|
| 3645 | + info->max_entries = val; |
---|
| 3646 | + else if (sscanf(buff, "map_flags:\t%i", &val) == 1) |
---|
| 3647 | + info->map_flags = val; |
---|
1010 | 3648 | } |
---|
1011 | 3649 | |
---|
1012 | | - container_type = btf__type_by_id(btf, container_id); |
---|
1013 | | - if (!container_type) { |
---|
1014 | | - pr_warning("map:%s cannot find BTF type for container_id:%u\n", |
---|
1015 | | - map->name, container_id); |
---|
1016 | | - return -EINVAL; |
---|
1017 | | - } |
---|
1018 | | - |
---|
1019 | | - if (BTF_INFO_KIND(container_type->info) != BTF_KIND_STRUCT || |
---|
1020 | | - BTF_INFO_VLEN(container_type->info) < 2) { |
---|
1021 | | - pr_warning("map:%s container_name:%s is an invalid container struct\n", |
---|
1022 | | - map->name, container_name); |
---|
1023 | | - return -EINVAL; |
---|
1024 | | - } |
---|
1025 | | - |
---|
1026 | | - key = (struct btf_member *)(container_type + 1); |
---|
1027 | | - value = key + 1; |
---|
1028 | | - |
---|
1029 | | - key_size = btf__resolve_size(btf, key->type); |
---|
1030 | | - if (key_size < 0) { |
---|
1031 | | - pr_warning("map:%s invalid BTF key_type_size\n", |
---|
1032 | | - map->name); |
---|
1033 | | - return key_size; |
---|
1034 | | - } |
---|
1035 | | - |
---|
1036 | | - if (def->key_size != key_size) { |
---|
1037 | | - pr_warning("map:%s btf_key_type_size:%u != map_def_key_size:%u\n", |
---|
1038 | | - map->name, (__u32)key_size, def->key_size); |
---|
1039 | | - return -EINVAL; |
---|
1040 | | - } |
---|
1041 | | - |
---|
1042 | | - value_size = btf__resolve_size(btf, value->type); |
---|
1043 | | - if (value_size < 0) { |
---|
1044 | | - pr_warning("map:%s invalid BTF value_type_size\n", map->name); |
---|
1045 | | - return value_size; |
---|
1046 | | - } |
---|
1047 | | - |
---|
1048 | | - if (def->value_size != value_size) { |
---|
1049 | | - pr_warning("map:%s btf_value_type_size:%u != map_def_value_size:%u\n", |
---|
1050 | | - map->name, (__u32)value_size, def->value_size); |
---|
1051 | | - return -EINVAL; |
---|
1052 | | - } |
---|
1053 | | - |
---|
1054 | | - map->btf_key_type_id = key->type; |
---|
1055 | | - map->btf_value_type_id = value->type; |
---|
| 3650 | + fclose(fp); |
---|
1056 | 3651 | |
---|
1057 | 3652 | return 0; |
---|
1058 | 3653 | } |
---|
.. | .. |
---|
1060 | 3655 | int bpf_map__reuse_fd(struct bpf_map *map, int fd) |
---|
1061 | 3656 | { |
---|
1062 | 3657 | struct bpf_map_info info = {}; |
---|
1063 | | - __u32 len = sizeof(info); |
---|
| 3658 | + __u32 len = sizeof(info), name_len; |
---|
1064 | 3659 | int new_fd, err; |
---|
1065 | 3660 | char *new_name; |
---|
1066 | 3661 | |
---|
1067 | 3662 | err = bpf_obj_get_info_by_fd(fd, &info, &len); |
---|
| 3663 | + if (err && errno == EINVAL) |
---|
| 3664 | + err = bpf_get_map_info_from_fdinfo(fd, &info); |
---|
1068 | 3665 | if (err) |
---|
1069 | 3666 | return err; |
---|
1070 | 3667 | |
---|
1071 | | - new_name = strdup(info.name); |
---|
| 3668 | + name_len = strlen(info.name); |
---|
| 3669 | + if (name_len == BPF_OBJ_NAME_LEN - 1 && strncmp(map->name, info.name, name_len) == 0) |
---|
| 3670 | + new_name = strdup(map->name); |
---|
| 3671 | + else |
---|
| 3672 | + new_name = strdup(info.name); |
---|
| 3673 | + |
---|
1072 | 3674 | if (!new_name) |
---|
1073 | 3675 | return -errno; |
---|
1074 | 3676 | |
---|
.. | .. |
---|
1100 | 3702 | map->def.map_flags = info.map_flags; |
---|
1101 | 3703 | map->btf_key_type_id = info.btf_key_type_id; |
---|
1102 | 3704 | map->btf_value_type_id = info.btf_value_type_id; |
---|
| 3705 | + map->reused = true; |
---|
1103 | 3706 | |
---|
1104 | 3707 | return 0; |
---|
1105 | 3708 | |
---|
.. | .. |
---|
1110 | 3713 | return err; |
---|
1111 | 3714 | } |
---|
1112 | 3715 | |
---|
1113 | | -static int |
---|
1114 | | -bpf_object__create_maps(struct bpf_object *obj) |
---|
| 3716 | +__u32 bpf_map__max_entries(const struct bpf_map *map) |
---|
1115 | 3717 | { |
---|
1116 | | - struct bpf_create_map_attr create_attr = {}; |
---|
1117 | | - unsigned int i; |
---|
| 3718 | + return map->def.max_entries; |
---|
| 3719 | +} |
---|
| 3720 | + |
---|
| 3721 | +int bpf_map__set_max_entries(struct bpf_map *map, __u32 max_entries) |
---|
| 3722 | +{ |
---|
| 3723 | + if (map->fd >= 0) |
---|
| 3724 | + return -EBUSY; |
---|
| 3725 | + map->def.max_entries = max_entries; |
---|
| 3726 | + return 0; |
---|
| 3727 | +} |
---|
| 3728 | + |
---|
| 3729 | +int bpf_map__resize(struct bpf_map *map, __u32 max_entries) |
---|
| 3730 | +{ |
---|
| 3731 | + if (!map || !max_entries) |
---|
| 3732 | + return -EINVAL; |
---|
| 3733 | + |
---|
| 3734 | + return bpf_map__set_max_entries(map, max_entries); |
---|
| 3735 | +} |
---|
| 3736 | + |
---|
| 3737 | +static int |
---|
| 3738 | +bpf_object__probe_loading(struct bpf_object *obj) |
---|
| 3739 | +{ |
---|
| 3740 | + struct bpf_load_program_attr attr; |
---|
| 3741 | + char *cp, errmsg[STRERR_BUFSIZE]; |
---|
| 3742 | + struct bpf_insn insns[] = { |
---|
| 3743 | + BPF_MOV64_IMM(BPF_REG_0, 0), |
---|
| 3744 | + BPF_EXIT_INSN(), |
---|
| 3745 | + }; |
---|
| 3746 | + int ret; |
---|
| 3747 | + |
---|
| 3748 | + /* make sure basic loading works */ |
---|
| 3749 | + |
---|
| 3750 | + memset(&attr, 0, sizeof(attr)); |
---|
| 3751 | + attr.prog_type = BPF_PROG_TYPE_SOCKET_FILTER; |
---|
| 3752 | + attr.insns = insns; |
---|
| 3753 | + attr.insns_cnt = ARRAY_SIZE(insns); |
---|
| 3754 | + attr.license = "GPL"; |
---|
| 3755 | + |
---|
| 3756 | + ret = bpf_load_program_xattr(&attr, NULL, 0); |
---|
| 3757 | + if (ret < 0) { |
---|
| 3758 | + ret = errno; |
---|
| 3759 | + cp = libbpf_strerror_r(ret, errmsg, sizeof(errmsg)); |
---|
| 3760 | + pr_warn("Error in %s():%s(%d). Couldn't load trivial BPF " |
---|
| 3761 | + "program. Make sure your kernel supports BPF " |
---|
| 3762 | + "(CONFIG_BPF_SYSCALL=y) and/or that RLIMIT_MEMLOCK is " |
---|
| 3763 | + "set to big enough value.\n", __func__, cp, ret); |
---|
| 3764 | + return -ret; |
---|
| 3765 | + } |
---|
| 3766 | + close(ret); |
---|
| 3767 | + |
---|
| 3768 | + return 0; |
---|
| 3769 | +} |
---|
| 3770 | + |
---|
| 3771 | +static int probe_fd(int fd) |
---|
| 3772 | +{ |
---|
| 3773 | + if (fd >= 0) |
---|
| 3774 | + close(fd); |
---|
| 3775 | + return fd >= 0; |
---|
| 3776 | +} |
---|
| 3777 | + |
---|
| 3778 | +static int probe_kern_prog_name(void) |
---|
| 3779 | +{ |
---|
| 3780 | + struct bpf_load_program_attr attr; |
---|
| 3781 | + struct bpf_insn insns[] = { |
---|
| 3782 | + BPF_MOV64_IMM(BPF_REG_0, 0), |
---|
| 3783 | + BPF_EXIT_INSN(), |
---|
| 3784 | + }; |
---|
| 3785 | + int ret; |
---|
| 3786 | + |
---|
| 3787 | + /* make sure loading with name works */ |
---|
| 3788 | + |
---|
| 3789 | + memset(&attr, 0, sizeof(attr)); |
---|
| 3790 | + attr.prog_type = BPF_PROG_TYPE_SOCKET_FILTER; |
---|
| 3791 | + attr.insns = insns; |
---|
| 3792 | + attr.insns_cnt = ARRAY_SIZE(insns); |
---|
| 3793 | + attr.license = "GPL"; |
---|
| 3794 | + attr.name = "test"; |
---|
| 3795 | + ret = bpf_load_program_xattr(&attr, NULL, 0); |
---|
| 3796 | + return probe_fd(ret); |
---|
| 3797 | +} |
---|
| 3798 | + |
---|
| 3799 | +static int probe_kern_global_data(void) |
---|
| 3800 | +{ |
---|
| 3801 | + struct bpf_load_program_attr prg_attr; |
---|
| 3802 | + struct bpf_create_map_attr map_attr; |
---|
| 3803 | + char *cp, errmsg[STRERR_BUFSIZE]; |
---|
| 3804 | + struct bpf_insn insns[] = { |
---|
| 3805 | + BPF_LD_MAP_VALUE(BPF_REG_1, 0, 16), |
---|
| 3806 | + BPF_ST_MEM(BPF_DW, BPF_REG_1, 0, 42), |
---|
| 3807 | + BPF_MOV64_IMM(BPF_REG_0, 0), |
---|
| 3808 | + BPF_EXIT_INSN(), |
---|
| 3809 | + }; |
---|
| 3810 | + int ret, map; |
---|
| 3811 | + |
---|
| 3812 | + memset(&map_attr, 0, sizeof(map_attr)); |
---|
| 3813 | + map_attr.map_type = BPF_MAP_TYPE_ARRAY; |
---|
| 3814 | + map_attr.key_size = sizeof(int); |
---|
| 3815 | + map_attr.value_size = 32; |
---|
| 3816 | + map_attr.max_entries = 1; |
---|
| 3817 | + |
---|
| 3818 | + map = bpf_create_map_xattr(&map_attr); |
---|
| 3819 | + if (map < 0) { |
---|
| 3820 | + ret = -errno; |
---|
| 3821 | + cp = libbpf_strerror_r(ret, errmsg, sizeof(errmsg)); |
---|
| 3822 | + pr_warn("Error in %s():%s(%d). Couldn't create simple array map.\n", |
---|
| 3823 | + __func__, cp, -ret); |
---|
| 3824 | + return ret; |
---|
| 3825 | + } |
---|
| 3826 | + |
---|
| 3827 | + insns[0].imm = map; |
---|
| 3828 | + |
---|
| 3829 | + memset(&prg_attr, 0, sizeof(prg_attr)); |
---|
| 3830 | + prg_attr.prog_type = BPF_PROG_TYPE_SOCKET_FILTER; |
---|
| 3831 | + prg_attr.insns = insns; |
---|
| 3832 | + prg_attr.insns_cnt = ARRAY_SIZE(insns); |
---|
| 3833 | + prg_attr.license = "GPL"; |
---|
| 3834 | + |
---|
| 3835 | + ret = bpf_load_program_xattr(&prg_attr, NULL, 0); |
---|
| 3836 | + close(map); |
---|
| 3837 | + return probe_fd(ret); |
---|
| 3838 | +} |
---|
| 3839 | + |
---|
| 3840 | +static int probe_kern_btf(void) |
---|
| 3841 | +{ |
---|
| 3842 | + static const char strs[] = "\0int"; |
---|
| 3843 | + __u32 types[] = { |
---|
| 3844 | + /* int */ |
---|
| 3845 | + BTF_TYPE_INT_ENC(1, BTF_INT_SIGNED, 0, 32, 4), |
---|
| 3846 | + }; |
---|
| 3847 | + |
---|
| 3848 | + return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types), |
---|
| 3849 | + strs, sizeof(strs))); |
---|
| 3850 | +} |
---|
| 3851 | + |
---|
| 3852 | +static int probe_kern_btf_func(void) |
---|
| 3853 | +{ |
---|
| 3854 | + static const char strs[] = "\0int\0x\0a"; |
---|
| 3855 | + /* void x(int a) {} */ |
---|
| 3856 | + __u32 types[] = { |
---|
| 3857 | + /* int */ |
---|
| 3858 | + BTF_TYPE_INT_ENC(1, BTF_INT_SIGNED, 0, 32, 4), /* [1] */ |
---|
| 3859 | + /* FUNC_PROTO */ /* [2] */ |
---|
| 3860 | + BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_FUNC_PROTO, 0, 1), 0), |
---|
| 3861 | + BTF_PARAM_ENC(7, 1), |
---|
| 3862 | + /* FUNC x */ /* [3] */ |
---|
| 3863 | + BTF_TYPE_ENC(5, BTF_INFO_ENC(BTF_KIND_FUNC, 0, 0), 2), |
---|
| 3864 | + }; |
---|
| 3865 | + |
---|
| 3866 | + return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types), |
---|
| 3867 | + strs, sizeof(strs))); |
---|
| 3868 | +} |
---|
| 3869 | + |
---|
| 3870 | +static int probe_kern_btf_func_global(void) |
---|
| 3871 | +{ |
---|
| 3872 | + static const char strs[] = "\0int\0x\0a"; |
---|
| 3873 | + /* static void x(int a) {} */ |
---|
| 3874 | + __u32 types[] = { |
---|
| 3875 | + /* int */ |
---|
| 3876 | + BTF_TYPE_INT_ENC(1, BTF_INT_SIGNED, 0, 32, 4), /* [1] */ |
---|
| 3877 | + /* FUNC_PROTO */ /* [2] */ |
---|
| 3878 | + BTF_TYPE_ENC(0, BTF_INFO_ENC(BTF_KIND_FUNC_PROTO, 0, 1), 0), |
---|
| 3879 | + BTF_PARAM_ENC(7, 1), |
---|
| 3880 | + /* FUNC x BTF_FUNC_GLOBAL */ /* [3] */ |
---|
| 3881 | + BTF_TYPE_ENC(5, BTF_INFO_ENC(BTF_KIND_FUNC, 0, BTF_FUNC_GLOBAL), 2), |
---|
| 3882 | + }; |
---|
| 3883 | + |
---|
| 3884 | + return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types), |
---|
| 3885 | + strs, sizeof(strs))); |
---|
| 3886 | +} |
---|
| 3887 | + |
---|
| 3888 | +static int probe_kern_btf_datasec(void) |
---|
| 3889 | +{ |
---|
| 3890 | + static const char strs[] = "\0x\0.data"; |
---|
| 3891 | + /* static int a; */ |
---|
| 3892 | + __u32 types[] = { |
---|
| 3893 | + /* int */ |
---|
| 3894 | + BTF_TYPE_INT_ENC(0, BTF_INT_SIGNED, 0, 32, 4), /* [1] */ |
---|
| 3895 | + /* VAR x */ /* [2] */ |
---|
| 3896 | + BTF_TYPE_ENC(1, BTF_INFO_ENC(BTF_KIND_VAR, 0, 0), 1), |
---|
| 3897 | + BTF_VAR_STATIC, |
---|
| 3898 | + /* DATASEC val */ /* [3] */ |
---|
| 3899 | + BTF_TYPE_ENC(3, BTF_INFO_ENC(BTF_KIND_DATASEC, 0, 1), 4), |
---|
| 3900 | + BTF_VAR_SECINFO_ENC(2, 0, 4), |
---|
| 3901 | + }; |
---|
| 3902 | + |
---|
| 3903 | + return probe_fd(libbpf__load_raw_btf((char *)types, sizeof(types), |
---|
| 3904 | + strs, sizeof(strs))); |
---|
| 3905 | +} |
---|
| 3906 | + |
---|
| 3907 | +static int probe_kern_array_mmap(void) |
---|
| 3908 | +{ |
---|
| 3909 | + struct bpf_create_map_attr attr = { |
---|
| 3910 | + .map_type = BPF_MAP_TYPE_ARRAY, |
---|
| 3911 | + .map_flags = BPF_F_MMAPABLE, |
---|
| 3912 | + .key_size = sizeof(int), |
---|
| 3913 | + .value_size = sizeof(int), |
---|
| 3914 | + .max_entries = 1, |
---|
| 3915 | + }; |
---|
| 3916 | + |
---|
| 3917 | + return probe_fd(bpf_create_map_xattr(&attr)); |
---|
| 3918 | +} |
---|
| 3919 | + |
---|
| 3920 | +static int probe_kern_exp_attach_type(void) |
---|
| 3921 | +{ |
---|
| 3922 | + struct bpf_load_program_attr attr; |
---|
| 3923 | + struct bpf_insn insns[] = { |
---|
| 3924 | + BPF_MOV64_IMM(BPF_REG_0, 0), |
---|
| 3925 | + BPF_EXIT_INSN(), |
---|
| 3926 | + }; |
---|
| 3927 | + |
---|
| 3928 | + memset(&attr, 0, sizeof(attr)); |
---|
| 3929 | + /* use any valid combination of program type and (optional) |
---|
| 3930 | + * non-zero expected attach type (i.e., not a BPF_CGROUP_INET_INGRESS) |
---|
| 3931 | + * to see if kernel supports expected_attach_type field for |
---|
| 3932 | + * BPF_PROG_LOAD command |
---|
| 3933 | + */ |
---|
| 3934 | + attr.prog_type = BPF_PROG_TYPE_CGROUP_SOCK; |
---|
| 3935 | + attr.expected_attach_type = BPF_CGROUP_INET_SOCK_CREATE; |
---|
| 3936 | + attr.insns = insns; |
---|
| 3937 | + attr.insns_cnt = ARRAY_SIZE(insns); |
---|
| 3938 | + attr.license = "GPL"; |
---|
| 3939 | + |
---|
| 3940 | + return probe_fd(bpf_load_program_xattr(&attr, NULL, 0)); |
---|
| 3941 | +} |
---|
| 3942 | + |
---|
| 3943 | +static int probe_kern_probe_read_kernel(void) |
---|
| 3944 | +{ |
---|
| 3945 | + struct bpf_load_program_attr attr; |
---|
| 3946 | + struct bpf_insn insns[] = { |
---|
| 3947 | + BPF_MOV64_REG(BPF_REG_1, BPF_REG_10), /* r1 = r10 (fp) */ |
---|
| 3948 | + BPF_ALU64_IMM(BPF_ADD, BPF_REG_1, -8), /* r1 += -8 */ |
---|
| 3949 | + BPF_MOV64_IMM(BPF_REG_2, 8), /* r2 = 8 */ |
---|
| 3950 | + BPF_MOV64_IMM(BPF_REG_3, 0), /* r3 = 0 */ |
---|
| 3951 | + BPF_RAW_INSN(BPF_JMP | BPF_CALL, 0, 0, 0, BPF_FUNC_probe_read_kernel), |
---|
| 3952 | + BPF_EXIT_INSN(), |
---|
| 3953 | + }; |
---|
| 3954 | + |
---|
| 3955 | + memset(&attr, 0, sizeof(attr)); |
---|
| 3956 | + attr.prog_type = BPF_PROG_TYPE_KPROBE; |
---|
| 3957 | + attr.insns = insns; |
---|
| 3958 | + attr.insns_cnt = ARRAY_SIZE(insns); |
---|
| 3959 | + attr.license = "GPL"; |
---|
| 3960 | + |
---|
| 3961 | + return probe_fd(bpf_load_program_xattr(&attr, NULL, 0)); |
---|
| 3962 | +} |
---|
| 3963 | + |
---|
| 3964 | +static int probe_prog_bind_map(void) |
---|
| 3965 | +{ |
---|
| 3966 | + struct bpf_load_program_attr prg_attr; |
---|
| 3967 | + struct bpf_create_map_attr map_attr; |
---|
| 3968 | + char *cp, errmsg[STRERR_BUFSIZE]; |
---|
| 3969 | + struct bpf_insn insns[] = { |
---|
| 3970 | + BPF_MOV64_IMM(BPF_REG_0, 0), |
---|
| 3971 | + BPF_EXIT_INSN(), |
---|
| 3972 | + }; |
---|
| 3973 | + int ret, map, prog; |
---|
| 3974 | + |
---|
| 3975 | + memset(&map_attr, 0, sizeof(map_attr)); |
---|
| 3976 | + map_attr.map_type = BPF_MAP_TYPE_ARRAY; |
---|
| 3977 | + map_attr.key_size = sizeof(int); |
---|
| 3978 | + map_attr.value_size = 32; |
---|
| 3979 | + map_attr.max_entries = 1; |
---|
| 3980 | + |
---|
| 3981 | + map = bpf_create_map_xattr(&map_attr); |
---|
| 3982 | + if (map < 0) { |
---|
| 3983 | + ret = -errno; |
---|
| 3984 | + cp = libbpf_strerror_r(ret, errmsg, sizeof(errmsg)); |
---|
| 3985 | + pr_warn("Error in %s():%s(%d). Couldn't create simple array map.\n", |
---|
| 3986 | + __func__, cp, -ret); |
---|
| 3987 | + return ret; |
---|
| 3988 | + } |
---|
| 3989 | + |
---|
| 3990 | + memset(&prg_attr, 0, sizeof(prg_attr)); |
---|
| 3991 | + prg_attr.prog_type = BPF_PROG_TYPE_SOCKET_FILTER; |
---|
| 3992 | + prg_attr.insns = insns; |
---|
| 3993 | + prg_attr.insns_cnt = ARRAY_SIZE(insns); |
---|
| 3994 | + prg_attr.license = "GPL"; |
---|
| 3995 | + |
---|
| 3996 | + prog = bpf_load_program_xattr(&prg_attr, NULL, 0); |
---|
| 3997 | + if (prog < 0) { |
---|
| 3998 | + close(map); |
---|
| 3999 | + return 0; |
---|
| 4000 | + } |
---|
| 4001 | + |
---|
| 4002 | + ret = bpf_prog_bind_map(prog, map, NULL); |
---|
| 4003 | + |
---|
| 4004 | + close(map); |
---|
| 4005 | + close(prog); |
---|
| 4006 | + |
---|
| 4007 | + return ret >= 0; |
---|
| 4008 | +} |
---|
| 4009 | + |
---|
| 4010 | +enum kern_feature_result { |
---|
| 4011 | + FEAT_UNKNOWN = 0, |
---|
| 4012 | + FEAT_SUPPORTED = 1, |
---|
| 4013 | + FEAT_MISSING = 2, |
---|
| 4014 | +}; |
---|
| 4015 | + |
---|
| 4016 | +typedef int (*feature_probe_fn)(void); |
---|
| 4017 | + |
---|
| 4018 | +static struct kern_feature_desc { |
---|
| 4019 | + const char *desc; |
---|
| 4020 | + feature_probe_fn probe; |
---|
| 4021 | + enum kern_feature_result res; |
---|
| 4022 | +} feature_probes[__FEAT_CNT] = { |
---|
| 4023 | + [FEAT_PROG_NAME] = { |
---|
| 4024 | + "BPF program name", probe_kern_prog_name, |
---|
| 4025 | + }, |
---|
| 4026 | + [FEAT_GLOBAL_DATA] = { |
---|
| 4027 | + "global variables", probe_kern_global_data, |
---|
| 4028 | + }, |
---|
| 4029 | + [FEAT_BTF] = { |
---|
| 4030 | + "minimal BTF", probe_kern_btf, |
---|
| 4031 | + }, |
---|
| 4032 | + [FEAT_BTF_FUNC] = { |
---|
| 4033 | + "BTF functions", probe_kern_btf_func, |
---|
| 4034 | + }, |
---|
| 4035 | + [FEAT_BTF_GLOBAL_FUNC] = { |
---|
| 4036 | + "BTF global function", probe_kern_btf_func_global, |
---|
| 4037 | + }, |
---|
| 4038 | + [FEAT_BTF_DATASEC] = { |
---|
| 4039 | + "BTF data section and variable", probe_kern_btf_datasec, |
---|
| 4040 | + }, |
---|
| 4041 | + [FEAT_ARRAY_MMAP] = { |
---|
| 4042 | + "ARRAY map mmap()", probe_kern_array_mmap, |
---|
| 4043 | + }, |
---|
| 4044 | + [FEAT_EXP_ATTACH_TYPE] = { |
---|
| 4045 | + "BPF_PROG_LOAD expected_attach_type attribute", |
---|
| 4046 | + probe_kern_exp_attach_type, |
---|
| 4047 | + }, |
---|
| 4048 | + [FEAT_PROBE_READ_KERN] = { |
---|
| 4049 | + "bpf_probe_read_kernel() helper", probe_kern_probe_read_kernel, |
---|
| 4050 | + }, |
---|
| 4051 | + [FEAT_PROG_BIND_MAP] = { |
---|
| 4052 | + "BPF_PROG_BIND_MAP support", probe_prog_bind_map, |
---|
| 4053 | + } |
---|
| 4054 | +}; |
---|
| 4055 | + |
---|
| 4056 | +static bool kernel_supports(enum kern_feature_id feat_id) |
---|
| 4057 | +{ |
---|
| 4058 | + struct kern_feature_desc *feat = &feature_probes[feat_id]; |
---|
| 4059 | + int ret; |
---|
| 4060 | + |
---|
| 4061 | + if (READ_ONCE(feat->res) == FEAT_UNKNOWN) { |
---|
| 4062 | + ret = feat->probe(); |
---|
| 4063 | + if (ret > 0) { |
---|
| 4064 | + WRITE_ONCE(feat->res, FEAT_SUPPORTED); |
---|
| 4065 | + } else if (ret == 0) { |
---|
| 4066 | + WRITE_ONCE(feat->res, FEAT_MISSING); |
---|
| 4067 | + } else { |
---|
| 4068 | + pr_warn("Detection of kernel %s support failed: %d\n", feat->desc, ret); |
---|
| 4069 | + WRITE_ONCE(feat->res, FEAT_MISSING); |
---|
| 4070 | + } |
---|
| 4071 | + } |
---|
| 4072 | + |
---|
| 4073 | + return READ_ONCE(feat->res) == FEAT_SUPPORTED; |
---|
| 4074 | +} |
---|
| 4075 | + |
---|
| 4076 | +static bool map_is_reuse_compat(const struct bpf_map *map, int map_fd) |
---|
| 4077 | +{ |
---|
| 4078 | + struct bpf_map_info map_info = {}; |
---|
| 4079 | + char msg[STRERR_BUFSIZE]; |
---|
| 4080 | + __u32 map_info_len; |
---|
1118 | 4081 | int err; |
---|
1119 | 4082 | |
---|
1120 | | - for (i = 0; i < obj->nr_maps; i++) { |
---|
1121 | | - struct bpf_map *map = &obj->maps[i]; |
---|
1122 | | - struct bpf_map_def *def = &map->def; |
---|
1123 | | - char *cp, errmsg[STRERR_BUFSIZE]; |
---|
1124 | | - int *pfd = &map->fd; |
---|
| 4083 | + map_info_len = sizeof(map_info); |
---|
1125 | 4084 | |
---|
1126 | | - if (map->fd >= 0) { |
---|
1127 | | - pr_debug("skip map create (preset) %s: fd=%d\n", |
---|
1128 | | - map->name, map->fd); |
---|
1129 | | - continue; |
---|
| 4085 | + err = bpf_obj_get_info_by_fd(map_fd, &map_info, &map_info_len); |
---|
| 4086 | + if (err && errno == EINVAL) |
---|
| 4087 | + err = bpf_get_map_info_from_fdinfo(map_fd, &map_info); |
---|
| 4088 | + if (err) { |
---|
| 4089 | + pr_warn("failed to get map info for map FD %d: %s\n", map_fd, |
---|
| 4090 | + libbpf_strerror_r(errno, msg, sizeof(msg))); |
---|
| 4091 | + return false; |
---|
| 4092 | + } |
---|
| 4093 | + |
---|
| 4094 | + return (map_info.type == map->def.type && |
---|
| 4095 | + map_info.key_size == map->def.key_size && |
---|
| 4096 | + map_info.value_size == map->def.value_size && |
---|
| 4097 | + map_info.max_entries == map->def.max_entries && |
---|
| 4098 | + map_info.map_flags == map->def.map_flags); |
---|
| 4099 | +} |
---|
| 4100 | + |
---|
| 4101 | +static int |
---|
| 4102 | +bpf_object__reuse_map(struct bpf_map *map) |
---|
| 4103 | +{ |
---|
| 4104 | + char *cp, errmsg[STRERR_BUFSIZE]; |
---|
| 4105 | + int err, pin_fd; |
---|
| 4106 | + |
---|
| 4107 | + pin_fd = bpf_obj_get(map->pin_path); |
---|
| 4108 | + if (pin_fd < 0) { |
---|
| 4109 | + err = -errno; |
---|
| 4110 | + if (err == -ENOENT) { |
---|
| 4111 | + pr_debug("found no pinned map to reuse at '%s'\n", |
---|
| 4112 | + map->pin_path); |
---|
| 4113 | + return 0; |
---|
1130 | 4114 | } |
---|
1131 | 4115 | |
---|
| 4116 | + cp = libbpf_strerror_r(-err, errmsg, sizeof(errmsg)); |
---|
| 4117 | + pr_warn("couldn't retrieve pinned map '%s': %s\n", |
---|
| 4118 | + map->pin_path, cp); |
---|
| 4119 | + return err; |
---|
| 4120 | + } |
---|
| 4121 | + |
---|
| 4122 | + if (!map_is_reuse_compat(map, pin_fd)) { |
---|
| 4123 | + pr_warn("couldn't reuse pinned map at '%s': parameter mismatch\n", |
---|
| 4124 | + map->pin_path); |
---|
| 4125 | + close(pin_fd); |
---|
| 4126 | + return -EINVAL; |
---|
| 4127 | + } |
---|
| 4128 | + |
---|
| 4129 | + err = bpf_map__reuse_fd(map, pin_fd); |
---|
| 4130 | + if (err) { |
---|
| 4131 | + close(pin_fd); |
---|
| 4132 | + return err; |
---|
| 4133 | + } |
---|
| 4134 | + map->pinned = true; |
---|
| 4135 | + pr_debug("reused pinned map at '%s'\n", map->pin_path); |
---|
| 4136 | + |
---|
| 4137 | + return 0; |
---|
| 4138 | +} |
---|
| 4139 | + |
---|
| 4140 | +static int |
---|
| 4141 | +bpf_object__populate_internal_map(struct bpf_object *obj, struct bpf_map *map) |
---|
| 4142 | +{ |
---|
| 4143 | + enum libbpf_map_type map_type = map->libbpf_type; |
---|
| 4144 | + char *cp, errmsg[STRERR_BUFSIZE]; |
---|
| 4145 | + int err, zero = 0; |
---|
| 4146 | + |
---|
| 4147 | + err = bpf_map_update_elem(map->fd, &zero, map->mmaped, 0); |
---|
| 4148 | + if (err) { |
---|
| 4149 | + err = -errno; |
---|
| 4150 | + cp = libbpf_strerror_r(err, errmsg, sizeof(errmsg)); |
---|
| 4151 | + pr_warn("Error setting initial map(%s) contents: %s\n", |
---|
| 4152 | + map->name, cp); |
---|
| 4153 | + return err; |
---|
| 4154 | + } |
---|
| 4155 | + |
---|
| 4156 | + /* Freeze .rodata and .kconfig map as read-only from syscall side. */ |
---|
| 4157 | + if (map_type == LIBBPF_MAP_RODATA || map_type == LIBBPF_MAP_KCONFIG) { |
---|
| 4158 | + err = bpf_map_freeze(map->fd); |
---|
| 4159 | + if (err) { |
---|
| 4160 | + err = -errno; |
---|
| 4161 | + cp = libbpf_strerror_r(err, errmsg, sizeof(errmsg)); |
---|
| 4162 | + pr_warn("Error freezing map(%s) as read-only: %s\n", |
---|
| 4163 | + map->name, cp); |
---|
| 4164 | + return err; |
---|
| 4165 | + } |
---|
| 4166 | + } |
---|
| 4167 | + return 0; |
---|
| 4168 | +} |
---|
| 4169 | + |
---|
| 4170 | +static void bpf_map__destroy(struct bpf_map *map); |
---|
| 4171 | + |
---|
| 4172 | +static int bpf_object__create_map(struct bpf_object *obj, struct bpf_map *map) |
---|
| 4173 | +{ |
---|
| 4174 | + struct bpf_create_map_attr create_attr; |
---|
| 4175 | + struct bpf_map_def *def = &map->def; |
---|
| 4176 | + int err = 0; |
---|
| 4177 | + |
---|
| 4178 | + memset(&create_attr, 0, sizeof(create_attr)); |
---|
| 4179 | + |
---|
| 4180 | + if (kernel_supports(FEAT_PROG_NAME)) |
---|
1132 | 4181 | create_attr.name = map->name; |
---|
1133 | | - create_attr.map_ifindex = map->map_ifindex; |
---|
1134 | | - create_attr.map_type = def->type; |
---|
1135 | | - create_attr.map_flags = def->map_flags; |
---|
1136 | | - create_attr.key_size = def->key_size; |
---|
1137 | | - create_attr.value_size = def->value_size; |
---|
| 4182 | + create_attr.map_ifindex = map->map_ifindex; |
---|
| 4183 | + create_attr.map_type = def->type; |
---|
| 4184 | + create_attr.map_flags = def->map_flags; |
---|
| 4185 | + create_attr.key_size = def->key_size; |
---|
| 4186 | + create_attr.value_size = def->value_size; |
---|
| 4187 | + create_attr.numa_node = map->numa_node; |
---|
| 4188 | + |
---|
| 4189 | + if (def->type == BPF_MAP_TYPE_PERF_EVENT_ARRAY && !def->max_entries) { |
---|
| 4190 | + int nr_cpus; |
---|
| 4191 | + |
---|
| 4192 | + nr_cpus = libbpf_num_possible_cpus(); |
---|
| 4193 | + if (nr_cpus < 0) { |
---|
| 4194 | + pr_warn("map '%s': failed to determine number of system CPUs: %d\n", |
---|
| 4195 | + map->name, nr_cpus); |
---|
| 4196 | + return nr_cpus; |
---|
| 4197 | + } |
---|
| 4198 | + pr_debug("map '%s': setting size to %d\n", map->name, nr_cpus); |
---|
| 4199 | + create_attr.max_entries = nr_cpus; |
---|
| 4200 | + } else { |
---|
1138 | 4201 | create_attr.max_entries = def->max_entries; |
---|
| 4202 | + } |
---|
| 4203 | + |
---|
| 4204 | + if (bpf_map__is_struct_ops(map)) |
---|
| 4205 | + create_attr.btf_vmlinux_value_type_id = |
---|
| 4206 | + map->btf_vmlinux_value_type_id; |
---|
| 4207 | + |
---|
| 4208 | + create_attr.btf_fd = 0; |
---|
| 4209 | + create_attr.btf_key_type_id = 0; |
---|
| 4210 | + create_attr.btf_value_type_id = 0; |
---|
| 4211 | + if (obj->btf && btf__fd(obj->btf) >= 0 && !bpf_map_find_btf_info(obj, map)) { |
---|
| 4212 | + create_attr.btf_fd = btf__fd(obj->btf); |
---|
| 4213 | + create_attr.btf_key_type_id = map->btf_key_type_id; |
---|
| 4214 | + create_attr.btf_value_type_id = map->btf_value_type_id; |
---|
| 4215 | + } |
---|
| 4216 | + |
---|
| 4217 | + if (bpf_map_type__is_map_in_map(def->type)) { |
---|
| 4218 | + if (map->inner_map) { |
---|
| 4219 | + err = bpf_object__create_map(obj, map->inner_map); |
---|
| 4220 | + if (err) { |
---|
| 4221 | + pr_warn("map '%s': failed to create inner map: %d\n", |
---|
| 4222 | + map->name, err); |
---|
| 4223 | + return err; |
---|
| 4224 | + } |
---|
| 4225 | + map->inner_map_fd = bpf_map__fd(map->inner_map); |
---|
| 4226 | + } |
---|
| 4227 | + if (map->inner_map_fd >= 0) |
---|
| 4228 | + create_attr.inner_map_fd = map->inner_map_fd; |
---|
| 4229 | + } |
---|
| 4230 | + |
---|
| 4231 | + map->fd = bpf_create_map_xattr(&create_attr); |
---|
| 4232 | + if (map->fd < 0 && (create_attr.btf_key_type_id || |
---|
| 4233 | + create_attr.btf_value_type_id)) { |
---|
| 4234 | + char *cp, errmsg[STRERR_BUFSIZE]; |
---|
| 4235 | + |
---|
| 4236 | + err = -errno; |
---|
| 4237 | + cp = libbpf_strerror_r(err, errmsg, sizeof(errmsg)); |
---|
| 4238 | + pr_warn("Error in bpf_create_map_xattr(%s):%s(%d). Retrying without BTF.\n", |
---|
| 4239 | + map->name, cp, err); |
---|
1139 | 4240 | create_attr.btf_fd = 0; |
---|
1140 | 4241 | create_attr.btf_key_type_id = 0; |
---|
1141 | 4242 | create_attr.btf_value_type_id = 0; |
---|
| 4243 | + map->btf_key_type_id = 0; |
---|
| 4244 | + map->btf_value_type_id = 0; |
---|
| 4245 | + map->fd = bpf_create_map_xattr(&create_attr); |
---|
| 4246 | + } |
---|
1142 | 4247 | |
---|
1143 | | - if (obj->btf && !bpf_map_find_btf_info(map, obj->btf)) { |
---|
1144 | | - create_attr.btf_fd = btf__fd(obj->btf); |
---|
1145 | | - create_attr.btf_key_type_id = map->btf_key_type_id; |
---|
1146 | | - create_attr.btf_value_type_id = map->btf_value_type_id; |
---|
1147 | | - } |
---|
| 4248 | + err = map->fd < 0 ? -errno : 0; |
---|
1148 | 4249 | |
---|
1149 | | - *pfd = bpf_create_map_xattr(&create_attr); |
---|
1150 | | - if (*pfd < 0 && create_attr.btf_key_type_id) { |
---|
1151 | | - cp = str_error(errno, errmsg, sizeof(errmsg)); |
---|
1152 | | - pr_warning("Error in bpf_create_map_xattr(%s):%s(%d). Retrying without BTF.\n", |
---|
1153 | | - map->name, cp, errno); |
---|
1154 | | - create_attr.btf_fd = 0; |
---|
1155 | | - create_attr.btf_key_type_id = 0; |
---|
1156 | | - create_attr.btf_value_type_id = 0; |
---|
1157 | | - map->btf_key_type_id = 0; |
---|
1158 | | - map->btf_value_type_id = 0; |
---|
1159 | | - *pfd = bpf_create_map_xattr(&create_attr); |
---|
1160 | | - } |
---|
| 4250 | + if (bpf_map_type__is_map_in_map(def->type) && map->inner_map) { |
---|
| 4251 | + bpf_map__destroy(map->inner_map); |
---|
| 4252 | + zfree(&map->inner_map); |
---|
| 4253 | + } |
---|
1161 | 4254 | |
---|
1162 | | - if (*pfd < 0) { |
---|
1163 | | - size_t j; |
---|
| 4255 | + return err; |
---|
| 4256 | +} |
---|
1164 | 4257 | |
---|
1165 | | - err = *pfd; |
---|
1166 | | - cp = str_error(errno, errmsg, sizeof(errmsg)); |
---|
1167 | | - pr_warning("failed to create map (name: '%s'): %s\n", |
---|
1168 | | - map->name, cp); |
---|
1169 | | - for (j = 0; j < i; j++) |
---|
1170 | | - zclose(obj->maps[j].fd); |
---|
| 4258 | +static int init_map_slots(struct bpf_map *map) |
---|
| 4259 | +{ |
---|
| 4260 | + const struct bpf_map *targ_map; |
---|
| 4261 | + unsigned int i; |
---|
| 4262 | + int fd, err; |
---|
| 4263 | + |
---|
| 4264 | + for (i = 0; i < map->init_slots_sz; i++) { |
---|
| 4265 | + if (!map->init_slots[i]) |
---|
| 4266 | + continue; |
---|
| 4267 | + |
---|
| 4268 | + targ_map = map->init_slots[i]; |
---|
| 4269 | + fd = bpf_map__fd(targ_map); |
---|
| 4270 | + err = bpf_map_update_elem(map->fd, &i, &fd, 0); |
---|
| 4271 | + if (err) { |
---|
| 4272 | + err = -errno; |
---|
| 4273 | + pr_warn("map '%s': failed to initialize slot [%d] to map '%s' fd=%d: %d\n", |
---|
| 4274 | + map->name, i, targ_map->name, |
---|
| 4275 | + fd, err); |
---|
1171 | 4276 | return err; |
---|
1172 | 4277 | } |
---|
1173 | | - pr_debug("create map %s: fd=%d\n", map->name, *pfd); |
---|
| 4278 | + pr_debug("map '%s': slot [%d] set to map '%s' fd=%d\n", |
---|
| 4279 | + map->name, i, targ_map->name, fd); |
---|
1174 | 4280 | } |
---|
| 4281 | + |
---|
| 4282 | + zfree(&map->init_slots); |
---|
| 4283 | + map->init_slots_sz = 0; |
---|
1175 | 4284 | |
---|
1176 | 4285 | return 0; |
---|
1177 | 4286 | } |
---|
1178 | 4287 | |
---|
1179 | 4288 | static int |
---|
1180 | | -bpf_program__reloc_text(struct bpf_program *prog, struct bpf_object *obj, |
---|
1181 | | - struct reloc_desc *relo) |
---|
| 4289 | +bpf_object__create_maps(struct bpf_object *obj) |
---|
1182 | 4290 | { |
---|
1183 | | - struct bpf_insn *insn, *new_insn; |
---|
1184 | | - struct bpf_program *text; |
---|
1185 | | - size_t new_cnt; |
---|
| 4291 | + struct bpf_map *map; |
---|
| 4292 | + char *cp, errmsg[STRERR_BUFSIZE]; |
---|
| 4293 | + unsigned int i, j; |
---|
| 4294 | + int err; |
---|
| 4295 | + bool retried; |
---|
1186 | 4296 | |
---|
1187 | | - if (relo->type != RELO_CALL) |
---|
1188 | | - return -LIBBPF_ERRNO__RELOC; |
---|
| 4297 | + for (i = 0; i < obj->nr_maps; i++) { |
---|
| 4298 | + map = &obj->maps[i]; |
---|
1189 | 4299 | |
---|
1190 | | - if (prog->idx == obj->efile.text_shndx) { |
---|
1191 | | - pr_warning("relo in .text insn %d into off %d\n", |
---|
1192 | | - relo->insn_idx, relo->text_off); |
---|
1193 | | - return -LIBBPF_ERRNO__RELOC; |
---|
| 4300 | + retried = false; |
---|
| 4301 | +retry: |
---|
| 4302 | + if (map->pin_path) { |
---|
| 4303 | + err = bpf_object__reuse_map(map); |
---|
| 4304 | + if (err) { |
---|
| 4305 | + pr_warn("map '%s': error reusing pinned map\n", |
---|
| 4306 | + map->name); |
---|
| 4307 | + goto err_out; |
---|
| 4308 | + } |
---|
| 4309 | + if (retried && map->fd < 0) { |
---|
| 4310 | + pr_warn("map '%s': cannot find pinned map\n", |
---|
| 4311 | + map->name); |
---|
| 4312 | + err = -ENOENT; |
---|
| 4313 | + goto err_out; |
---|
| 4314 | + } |
---|
| 4315 | + } |
---|
| 4316 | + |
---|
| 4317 | + if (map->fd >= 0) { |
---|
| 4318 | + pr_debug("map '%s': skipping creation (preset fd=%d)\n", |
---|
| 4319 | + map->name, map->fd); |
---|
| 4320 | + } else { |
---|
| 4321 | + err = bpf_object__create_map(obj, map); |
---|
| 4322 | + if (err) |
---|
| 4323 | + goto err_out; |
---|
| 4324 | + |
---|
| 4325 | + pr_debug("map '%s': created successfully, fd=%d\n", |
---|
| 4326 | + map->name, map->fd); |
---|
| 4327 | + |
---|
| 4328 | + if (bpf_map__is_internal(map)) { |
---|
| 4329 | + err = bpf_object__populate_internal_map(obj, map); |
---|
| 4330 | + if (err < 0) { |
---|
| 4331 | + zclose(map->fd); |
---|
| 4332 | + goto err_out; |
---|
| 4333 | + } |
---|
| 4334 | + } |
---|
| 4335 | + |
---|
| 4336 | + if (map->init_slots_sz) { |
---|
| 4337 | + err = init_map_slots(map); |
---|
| 4338 | + if (err < 0) { |
---|
| 4339 | + zclose(map->fd); |
---|
| 4340 | + goto err_out; |
---|
| 4341 | + } |
---|
| 4342 | + } |
---|
| 4343 | + } |
---|
| 4344 | + |
---|
| 4345 | + if (map->pin_path && !map->pinned) { |
---|
| 4346 | + err = bpf_map__pin(map, NULL); |
---|
| 4347 | + if (err) { |
---|
| 4348 | + zclose(map->fd); |
---|
| 4349 | + if (!retried && err == -EEXIST) { |
---|
| 4350 | + retried = true; |
---|
| 4351 | + goto retry; |
---|
| 4352 | + } |
---|
| 4353 | + pr_warn("map '%s': failed to auto-pin at '%s': %d\n", |
---|
| 4354 | + map->name, map->pin_path, err); |
---|
| 4355 | + goto err_out; |
---|
| 4356 | + } |
---|
| 4357 | + } |
---|
1194 | 4358 | } |
---|
1195 | 4359 | |
---|
1196 | | - if (prog->main_prog_cnt == 0) { |
---|
1197 | | - text = bpf_object__find_prog_by_idx(obj, obj->efile.text_shndx); |
---|
1198 | | - if (!text) { |
---|
1199 | | - pr_warning("no .text section found yet relo into text exist\n"); |
---|
1200 | | - return -LIBBPF_ERRNO__RELOC; |
---|
1201 | | - } |
---|
1202 | | - new_cnt = prog->insns_cnt + text->insns_cnt; |
---|
1203 | | - new_insn = reallocarray(prog->insns, new_cnt, sizeof(*insn)); |
---|
1204 | | - if (!new_insn) { |
---|
1205 | | - pr_warning("oom in prog realloc\n"); |
---|
1206 | | - return -ENOMEM; |
---|
1207 | | - } |
---|
1208 | | - memcpy(new_insn + prog->insns_cnt, text->insns, |
---|
1209 | | - text->insns_cnt * sizeof(*insn)); |
---|
1210 | | - prog->insns = new_insn; |
---|
1211 | | - prog->main_prog_cnt = prog->insns_cnt; |
---|
1212 | | - prog->insns_cnt = new_cnt; |
---|
1213 | | - pr_debug("added %zd insn from %s to prog %s\n", |
---|
1214 | | - text->insns_cnt, text->section_name, |
---|
1215 | | - prog->section_name); |
---|
| 4360 | + return 0; |
---|
| 4361 | + |
---|
| 4362 | +err_out: |
---|
| 4363 | + cp = libbpf_strerror_r(err, errmsg, sizeof(errmsg)); |
---|
| 4364 | + pr_warn("map '%s': failed to create: %s(%d)\n", map->name, cp, err); |
---|
| 4365 | + pr_perm_msg(err); |
---|
| 4366 | + for (j = 0; j < i; j++) |
---|
| 4367 | + zclose(obj->maps[j].fd); |
---|
| 4368 | + return err; |
---|
| 4369 | +} |
---|
| 4370 | + |
---|
| 4371 | +#define BPF_CORE_SPEC_MAX_LEN 64 |
---|
| 4372 | + |
---|
| 4373 | +/* represents BPF CO-RE field or array element accessor */ |
---|
| 4374 | +struct bpf_core_accessor { |
---|
| 4375 | + __u32 type_id; /* struct/union type or array element type */ |
---|
| 4376 | + __u32 idx; /* field index or array index */ |
---|
| 4377 | + const char *name; /* field name or NULL for array accessor */ |
---|
| 4378 | +}; |
---|
| 4379 | + |
---|
| 4380 | +struct bpf_core_spec { |
---|
| 4381 | + const struct btf *btf; |
---|
| 4382 | + /* high-level spec: named fields and array indices only */ |
---|
| 4383 | + struct bpf_core_accessor spec[BPF_CORE_SPEC_MAX_LEN]; |
---|
| 4384 | + /* original unresolved (no skip_mods_or_typedefs) root type ID */ |
---|
| 4385 | + __u32 root_type_id; |
---|
| 4386 | + /* CO-RE relocation kind */ |
---|
| 4387 | + enum bpf_core_relo_kind relo_kind; |
---|
| 4388 | + /* high-level spec length */ |
---|
| 4389 | + int len; |
---|
| 4390 | + /* raw, low-level spec: 1-to-1 with accessor spec string */ |
---|
| 4391 | + int raw_spec[BPF_CORE_SPEC_MAX_LEN]; |
---|
| 4392 | + /* raw spec length */ |
---|
| 4393 | + int raw_len; |
---|
| 4394 | + /* field bit offset represented by spec */ |
---|
| 4395 | + __u32 bit_offset; |
---|
| 4396 | +}; |
---|
| 4397 | + |
---|
| 4398 | +static bool str_is_empty(const char *s) |
---|
| 4399 | +{ |
---|
| 4400 | + return !s || !s[0]; |
---|
| 4401 | +} |
---|
| 4402 | + |
---|
| 4403 | +static bool is_flex_arr(const struct btf *btf, |
---|
| 4404 | + const struct bpf_core_accessor *acc, |
---|
| 4405 | + const struct btf_array *arr) |
---|
| 4406 | +{ |
---|
| 4407 | + const struct btf_type *t; |
---|
| 4408 | + |
---|
| 4409 | + /* not a flexible array, if not inside a struct or has non-zero size */ |
---|
| 4410 | + if (!acc->name || arr->nelems > 0) |
---|
| 4411 | + return false; |
---|
| 4412 | + |
---|
| 4413 | + /* has to be the last member of enclosing struct */ |
---|
| 4414 | + t = btf__type_by_id(btf, acc->type_id); |
---|
| 4415 | + return acc->idx == btf_vlen(t) - 1; |
---|
| 4416 | +} |
---|
| 4417 | + |
---|
| 4418 | +static const char *core_relo_kind_str(enum bpf_core_relo_kind kind) |
---|
| 4419 | +{ |
---|
| 4420 | + switch (kind) { |
---|
| 4421 | + case BPF_FIELD_BYTE_OFFSET: return "byte_off"; |
---|
| 4422 | + case BPF_FIELD_BYTE_SIZE: return "byte_sz"; |
---|
| 4423 | + case BPF_FIELD_EXISTS: return "field_exists"; |
---|
| 4424 | + case BPF_FIELD_SIGNED: return "signed"; |
---|
| 4425 | + case BPF_FIELD_LSHIFT_U64: return "lshift_u64"; |
---|
| 4426 | + case BPF_FIELD_RSHIFT_U64: return "rshift_u64"; |
---|
| 4427 | + case BPF_TYPE_ID_LOCAL: return "local_type_id"; |
---|
| 4428 | + case BPF_TYPE_ID_TARGET: return "target_type_id"; |
---|
| 4429 | + case BPF_TYPE_EXISTS: return "type_exists"; |
---|
| 4430 | + case BPF_TYPE_SIZE: return "type_size"; |
---|
| 4431 | + case BPF_ENUMVAL_EXISTS: return "enumval_exists"; |
---|
| 4432 | + case BPF_ENUMVAL_VALUE: return "enumval_value"; |
---|
| 4433 | + default: return "unknown"; |
---|
1216 | 4434 | } |
---|
1217 | | - insn = &prog->insns[relo->insn_idx]; |
---|
1218 | | - insn->imm += prog->main_prog_cnt - relo->insn_idx; |
---|
| 4435 | +} |
---|
| 4436 | + |
---|
| 4437 | +static bool core_relo_is_field_based(enum bpf_core_relo_kind kind) |
---|
| 4438 | +{ |
---|
| 4439 | + switch (kind) { |
---|
| 4440 | + case BPF_FIELD_BYTE_OFFSET: |
---|
| 4441 | + case BPF_FIELD_BYTE_SIZE: |
---|
| 4442 | + case BPF_FIELD_EXISTS: |
---|
| 4443 | + case BPF_FIELD_SIGNED: |
---|
| 4444 | + case BPF_FIELD_LSHIFT_U64: |
---|
| 4445 | + case BPF_FIELD_RSHIFT_U64: |
---|
| 4446 | + return true; |
---|
| 4447 | + default: |
---|
| 4448 | + return false; |
---|
| 4449 | + } |
---|
| 4450 | +} |
---|
| 4451 | + |
---|
| 4452 | +static bool core_relo_is_type_based(enum bpf_core_relo_kind kind) |
---|
| 4453 | +{ |
---|
| 4454 | + switch (kind) { |
---|
| 4455 | + case BPF_TYPE_ID_LOCAL: |
---|
| 4456 | + case BPF_TYPE_ID_TARGET: |
---|
| 4457 | + case BPF_TYPE_EXISTS: |
---|
| 4458 | + case BPF_TYPE_SIZE: |
---|
| 4459 | + return true; |
---|
| 4460 | + default: |
---|
| 4461 | + return false; |
---|
| 4462 | + } |
---|
| 4463 | +} |
---|
| 4464 | + |
---|
| 4465 | +static bool core_relo_is_enumval_based(enum bpf_core_relo_kind kind) |
---|
| 4466 | +{ |
---|
| 4467 | + switch (kind) { |
---|
| 4468 | + case BPF_ENUMVAL_EXISTS: |
---|
| 4469 | + case BPF_ENUMVAL_VALUE: |
---|
| 4470 | + return true; |
---|
| 4471 | + default: |
---|
| 4472 | + return false; |
---|
| 4473 | + } |
---|
| 4474 | +} |
---|
| 4475 | + |
---|
| 4476 | +/* |
---|
| 4477 | + * Turn bpf_core_relo into a low- and high-level spec representation, |
---|
| 4478 | + * validating correctness along the way, as well as calculating resulting |
---|
| 4479 | + * field bit offset, specified by accessor string. Low-level spec captures |
---|
| 4480 | + * every single level of nestedness, including traversing anonymous |
---|
| 4481 | + * struct/union members. High-level one only captures semantically meaningful |
---|
| 4482 | + * "turning points": named fields and array indicies. |
---|
| 4483 | + * E.g., for this case: |
---|
| 4484 | + * |
---|
| 4485 | + * struct sample { |
---|
| 4486 | + * int __unimportant; |
---|
| 4487 | + * struct { |
---|
| 4488 | + * int __1; |
---|
| 4489 | + * int __2; |
---|
| 4490 | + * int a[7]; |
---|
| 4491 | + * }; |
---|
| 4492 | + * }; |
---|
| 4493 | + * |
---|
| 4494 | + * struct sample *s = ...; |
---|
| 4495 | + * |
---|
| 4496 | + * int x = &s->a[3]; // access string = '0:1:2:3' |
---|
| 4497 | + * |
---|
| 4498 | + * Low-level spec has 1:1 mapping with each element of access string (it's |
---|
| 4499 | + * just a parsed access string representation): [0, 1, 2, 3]. |
---|
| 4500 | + * |
---|
| 4501 | + * High-level spec will capture only 3 points: |
---|
| 4502 | + * - intial zero-index access by pointer (&s->... is the same as &s[0]...); |
---|
| 4503 | + * - field 'a' access (corresponds to '2' in low-level spec); |
---|
| 4504 | + * - array element #3 access (corresponds to '3' in low-level spec). |
---|
| 4505 | + * |
---|
| 4506 | + * Type-based relocations (TYPE_EXISTS/TYPE_SIZE, |
---|
| 4507 | + * TYPE_ID_LOCAL/TYPE_ID_TARGET) don't capture any field information. Their |
---|
| 4508 | + * spec and raw_spec are kept empty. |
---|
| 4509 | + * |
---|
| 4510 | + * Enum value-based relocations (ENUMVAL_EXISTS/ENUMVAL_VALUE) use access |
---|
| 4511 | + * string to specify enumerator's value index that need to be relocated. |
---|
| 4512 | + */ |
---|
| 4513 | +static int bpf_core_parse_spec(const struct btf *btf, |
---|
| 4514 | + __u32 type_id, |
---|
| 4515 | + const char *spec_str, |
---|
| 4516 | + enum bpf_core_relo_kind relo_kind, |
---|
| 4517 | + struct bpf_core_spec *spec) |
---|
| 4518 | +{ |
---|
| 4519 | + int access_idx, parsed_len, i; |
---|
| 4520 | + struct bpf_core_accessor *acc; |
---|
| 4521 | + const struct btf_type *t; |
---|
| 4522 | + const char *name; |
---|
| 4523 | + __u32 id; |
---|
| 4524 | + __s64 sz; |
---|
| 4525 | + |
---|
| 4526 | + if (str_is_empty(spec_str) || *spec_str == ':') |
---|
| 4527 | + return -EINVAL; |
---|
| 4528 | + |
---|
| 4529 | + memset(spec, 0, sizeof(*spec)); |
---|
| 4530 | + spec->btf = btf; |
---|
| 4531 | + spec->root_type_id = type_id; |
---|
| 4532 | + spec->relo_kind = relo_kind; |
---|
| 4533 | + |
---|
| 4534 | + /* type-based relocations don't have a field access string */ |
---|
| 4535 | + if (core_relo_is_type_based(relo_kind)) { |
---|
| 4536 | + if (strcmp(spec_str, "0")) |
---|
| 4537 | + return -EINVAL; |
---|
| 4538 | + return 0; |
---|
| 4539 | + } |
---|
| 4540 | + |
---|
| 4541 | + /* parse spec_str="0:1:2:3:4" into array raw_spec=[0, 1, 2, 3, 4] */ |
---|
| 4542 | + while (*spec_str) { |
---|
| 4543 | + if (*spec_str == ':') |
---|
| 4544 | + ++spec_str; |
---|
| 4545 | + if (sscanf(spec_str, "%d%n", &access_idx, &parsed_len) != 1) |
---|
| 4546 | + return -EINVAL; |
---|
| 4547 | + if (spec->raw_len == BPF_CORE_SPEC_MAX_LEN) |
---|
| 4548 | + return -E2BIG; |
---|
| 4549 | + spec_str += parsed_len; |
---|
| 4550 | + spec->raw_spec[spec->raw_len++] = access_idx; |
---|
| 4551 | + } |
---|
| 4552 | + |
---|
| 4553 | + if (spec->raw_len == 0) |
---|
| 4554 | + return -EINVAL; |
---|
| 4555 | + |
---|
| 4556 | + t = skip_mods_and_typedefs(btf, type_id, &id); |
---|
| 4557 | + if (!t) |
---|
| 4558 | + return -EINVAL; |
---|
| 4559 | + |
---|
| 4560 | + access_idx = spec->raw_spec[0]; |
---|
| 4561 | + acc = &spec->spec[0]; |
---|
| 4562 | + acc->type_id = id; |
---|
| 4563 | + acc->idx = access_idx; |
---|
| 4564 | + spec->len++; |
---|
| 4565 | + |
---|
| 4566 | + if (core_relo_is_enumval_based(relo_kind)) { |
---|
| 4567 | + if (!btf_is_enum(t) || spec->raw_len > 1 || access_idx >= btf_vlen(t)) |
---|
| 4568 | + return -EINVAL; |
---|
| 4569 | + |
---|
| 4570 | + /* record enumerator name in a first accessor */ |
---|
| 4571 | + acc->name = btf__name_by_offset(btf, btf_enum(t)[access_idx].name_off); |
---|
| 4572 | + return 0; |
---|
| 4573 | + } |
---|
| 4574 | + |
---|
| 4575 | + if (!core_relo_is_field_based(relo_kind)) |
---|
| 4576 | + return -EINVAL; |
---|
| 4577 | + |
---|
| 4578 | + sz = btf__resolve_size(btf, id); |
---|
| 4579 | + if (sz < 0) |
---|
| 4580 | + return sz; |
---|
| 4581 | + spec->bit_offset = access_idx * sz * 8; |
---|
| 4582 | + |
---|
| 4583 | + for (i = 1; i < spec->raw_len; i++) { |
---|
| 4584 | + t = skip_mods_and_typedefs(btf, id, &id); |
---|
| 4585 | + if (!t) |
---|
| 4586 | + return -EINVAL; |
---|
| 4587 | + |
---|
| 4588 | + access_idx = spec->raw_spec[i]; |
---|
| 4589 | + acc = &spec->spec[spec->len]; |
---|
| 4590 | + |
---|
| 4591 | + if (btf_is_composite(t)) { |
---|
| 4592 | + const struct btf_member *m; |
---|
| 4593 | + __u32 bit_offset; |
---|
| 4594 | + |
---|
| 4595 | + if (access_idx >= btf_vlen(t)) |
---|
| 4596 | + return -EINVAL; |
---|
| 4597 | + |
---|
| 4598 | + bit_offset = btf_member_bit_offset(t, access_idx); |
---|
| 4599 | + spec->bit_offset += bit_offset; |
---|
| 4600 | + |
---|
| 4601 | + m = btf_members(t) + access_idx; |
---|
| 4602 | + if (m->name_off) { |
---|
| 4603 | + name = btf__name_by_offset(btf, m->name_off); |
---|
| 4604 | + if (str_is_empty(name)) |
---|
| 4605 | + return -EINVAL; |
---|
| 4606 | + |
---|
| 4607 | + acc->type_id = id; |
---|
| 4608 | + acc->idx = access_idx; |
---|
| 4609 | + acc->name = name; |
---|
| 4610 | + spec->len++; |
---|
| 4611 | + } |
---|
| 4612 | + |
---|
| 4613 | + id = m->type; |
---|
| 4614 | + } else if (btf_is_array(t)) { |
---|
| 4615 | + const struct btf_array *a = btf_array(t); |
---|
| 4616 | + bool flex; |
---|
| 4617 | + |
---|
| 4618 | + t = skip_mods_and_typedefs(btf, a->type, &id); |
---|
| 4619 | + if (!t) |
---|
| 4620 | + return -EINVAL; |
---|
| 4621 | + |
---|
| 4622 | + flex = is_flex_arr(btf, acc - 1, a); |
---|
| 4623 | + if (!flex && access_idx >= a->nelems) |
---|
| 4624 | + return -EINVAL; |
---|
| 4625 | + |
---|
| 4626 | + spec->spec[spec->len].type_id = id; |
---|
| 4627 | + spec->spec[spec->len].idx = access_idx; |
---|
| 4628 | + spec->len++; |
---|
| 4629 | + |
---|
| 4630 | + sz = btf__resolve_size(btf, id); |
---|
| 4631 | + if (sz < 0) |
---|
| 4632 | + return sz; |
---|
| 4633 | + spec->bit_offset += access_idx * sz * 8; |
---|
| 4634 | + } else { |
---|
| 4635 | + pr_warn("relo for [%u] %s (at idx %d) captures type [%d] of unexpected kind %s\n", |
---|
| 4636 | + type_id, spec_str, i, id, btf_kind_str(t)); |
---|
| 4637 | + return -EINVAL; |
---|
| 4638 | + } |
---|
| 4639 | + } |
---|
| 4640 | + |
---|
1219 | 4641 | return 0; |
---|
1220 | 4642 | } |
---|
1221 | 4643 | |
---|
1222 | | -static int |
---|
1223 | | -bpf_program__relocate(struct bpf_program *prog, struct bpf_object *obj) |
---|
| 4644 | +static bool bpf_core_is_flavor_sep(const char *s) |
---|
1224 | 4645 | { |
---|
1225 | | - int i, err; |
---|
| 4646 | + /* check X___Y name pattern, where X and Y are not underscores */ |
---|
| 4647 | + return s[0] != '_' && /* X */ |
---|
| 4648 | + s[1] == '_' && s[2] == '_' && s[3] == '_' && /* ___ */ |
---|
| 4649 | + s[4] != '_'; /* Y */ |
---|
| 4650 | +} |
---|
1226 | 4651 | |
---|
1227 | | - if (!prog || !prog->reloc_desc) |
---|
| 4652 | +/* Given 'some_struct_name___with_flavor' return the length of a name prefix |
---|
| 4653 | + * before last triple underscore. Struct name part after last triple |
---|
| 4654 | + * underscore is ignored by BPF CO-RE relocation during relocation matching. |
---|
| 4655 | + */ |
---|
| 4656 | +static size_t bpf_core_essential_name_len(const char *name) |
---|
| 4657 | +{ |
---|
| 4658 | + size_t n = strlen(name); |
---|
| 4659 | + int i; |
---|
| 4660 | + |
---|
| 4661 | + for (i = n - 5; i >= 0; i--) { |
---|
| 4662 | + if (bpf_core_is_flavor_sep(name + i)) |
---|
| 4663 | + return i + 1; |
---|
| 4664 | + } |
---|
| 4665 | + return n; |
---|
| 4666 | +} |
---|
| 4667 | + |
---|
| 4668 | +/* dynamically sized list of type IDs */ |
---|
| 4669 | +struct ids_vec { |
---|
| 4670 | + __u32 *data; |
---|
| 4671 | + int len; |
---|
| 4672 | +}; |
---|
| 4673 | + |
---|
| 4674 | +static void bpf_core_free_cands(struct ids_vec *cand_ids) |
---|
| 4675 | +{ |
---|
| 4676 | + free(cand_ids->data); |
---|
| 4677 | + free(cand_ids); |
---|
| 4678 | +} |
---|
| 4679 | + |
---|
| 4680 | +static struct ids_vec *bpf_core_find_cands(const struct btf *local_btf, |
---|
| 4681 | + __u32 local_type_id, |
---|
| 4682 | + const struct btf *targ_btf) |
---|
| 4683 | +{ |
---|
| 4684 | + size_t local_essent_len, targ_essent_len; |
---|
| 4685 | + const char *local_name, *targ_name; |
---|
| 4686 | + const struct btf_type *t, *local_t; |
---|
| 4687 | + struct ids_vec *cand_ids; |
---|
| 4688 | + __u32 *new_ids; |
---|
| 4689 | + int i, err, n; |
---|
| 4690 | + |
---|
| 4691 | + local_t = btf__type_by_id(local_btf, local_type_id); |
---|
| 4692 | + if (!local_t) |
---|
| 4693 | + return ERR_PTR(-EINVAL); |
---|
| 4694 | + |
---|
| 4695 | + local_name = btf__name_by_offset(local_btf, local_t->name_off); |
---|
| 4696 | + if (str_is_empty(local_name)) |
---|
| 4697 | + return ERR_PTR(-EINVAL); |
---|
| 4698 | + local_essent_len = bpf_core_essential_name_len(local_name); |
---|
| 4699 | + |
---|
| 4700 | + cand_ids = calloc(1, sizeof(*cand_ids)); |
---|
| 4701 | + if (!cand_ids) |
---|
| 4702 | + return ERR_PTR(-ENOMEM); |
---|
| 4703 | + |
---|
| 4704 | + n = btf__get_nr_types(targ_btf); |
---|
| 4705 | + for (i = 1; i <= n; i++) { |
---|
| 4706 | + t = btf__type_by_id(targ_btf, i); |
---|
| 4707 | + if (btf_kind(t) != btf_kind(local_t)) |
---|
| 4708 | + continue; |
---|
| 4709 | + |
---|
| 4710 | + targ_name = btf__name_by_offset(targ_btf, t->name_off); |
---|
| 4711 | + if (str_is_empty(targ_name)) |
---|
| 4712 | + continue; |
---|
| 4713 | + |
---|
| 4714 | + targ_essent_len = bpf_core_essential_name_len(targ_name); |
---|
| 4715 | + if (targ_essent_len != local_essent_len) |
---|
| 4716 | + continue; |
---|
| 4717 | + |
---|
| 4718 | + if (strncmp(local_name, targ_name, local_essent_len) == 0) { |
---|
| 4719 | + pr_debug("CO-RE relocating [%d] %s %s: found target candidate [%d] %s %s\n", |
---|
| 4720 | + local_type_id, btf_kind_str(local_t), |
---|
| 4721 | + local_name, i, btf_kind_str(t), targ_name); |
---|
| 4722 | + new_ids = libbpf_reallocarray(cand_ids->data, |
---|
| 4723 | + cand_ids->len + 1, |
---|
| 4724 | + sizeof(*cand_ids->data)); |
---|
| 4725 | + if (!new_ids) { |
---|
| 4726 | + err = -ENOMEM; |
---|
| 4727 | + goto err_out; |
---|
| 4728 | + } |
---|
| 4729 | + cand_ids->data = new_ids; |
---|
| 4730 | + cand_ids->data[cand_ids->len++] = i; |
---|
| 4731 | + } |
---|
| 4732 | + } |
---|
| 4733 | + return cand_ids; |
---|
| 4734 | +err_out: |
---|
| 4735 | + bpf_core_free_cands(cand_ids); |
---|
| 4736 | + return ERR_PTR(err); |
---|
| 4737 | +} |
---|
| 4738 | + |
---|
| 4739 | +/* Check two types for compatibility for the purpose of field access |
---|
| 4740 | + * relocation. const/volatile/restrict and typedefs are skipped to ensure we |
---|
| 4741 | + * are relocating semantically compatible entities: |
---|
| 4742 | + * - any two STRUCTs/UNIONs are compatible and can be mixed; |
---|
| 4743 | + * - any two FWDs are compatible, if their names match (modulo flavor suffix); |
---|
| 4744 | + * - any two PTRs are always compatible; |
---|
| 4745 | + * - for ENUMs, names should be the same (ignoring flavor suffix) or at |
---|
| 4746 | + * least one of enums should be anonymous; |
---|
| 4747 | + * - for ENUMs, check sizes, names are ignored; |
---|
| 4748 | + * - for INT, size and signedness are ignored; |
---|
| 4749 | + * - for ARRAY, dimensionality is ignored, element types are checked for |
---|
| 4750 | + * compatibility recursively; |
---|
| 4751 | + * - everything else shouldn't be ever a target of relocation. |
---|
| 4752 | + * These rules are not set in stone and probably will be adjusted as we get |
---|
| 4753 | + * more experience with using BPF CO-RE relocations. |
---|
| 4754 | + */ |
---|
| 4755 | +static int bpf_core_fields_are_compat(const struct btf *local_btf, |
---|
| 4756 | + __u32 local_id, |
---|
| 4757 | + const struct btf *targ_btf, |
---|
| 4758 | + __u32 targ_id) |
---|
| 4759 | +{ |
---|
| 4760 | + const struct btf_type *local_type, *targ_type; |
---|
| 4761 | + |
---|
| 4762 | +recur: |
---|
| 4763 | + local_type = skip_mods_and_typedefs(local_btf, local_id, &local_id); |
---|
| 4764 | + targ_type = skip_mods_and_typedefs(targ_btf, targ_id, &targ_id); |
---|
| 4765 | + if (!local_type || !targ_type) |
---|
| 4766 | + return -EINVAL; |
---|
| 4767 | + |
---|
| 4768 | + if (btf_is_composite(local_type) && btf_is_composite(targ_type)) |
---|
| 4769 | + return 1; |
---|
| 4770 | + if (btf_kind(local_type) != btf_kind(targ_type)) |
---|
1228 | 4771 | return 0; |
---|
1229 | 4772 | |
---|
1230 | | - for (i = 0; i < prog->nr_reloc; i++) { |
---|
1231 | | - if (prog->reloc_desc[i].type == RELO_LD64) { |
---|
1232 | | - struct bpf_insn *insns = prog->insns; |
---|
1233 | | - int insn_idx, map_idx; |
---|
| 4773 | + switch (btf_kind(local_type)) { |
---|
| 4774 | + case BTF_KIND_PTR: |
---|
| 4775 | + return 1; |
---|
| 4776 | + case BTF_KIND_FWD: |
---|
| 4777 | + case BTF_KIND_ENUM: { |
---|
| 4778 | + const char *local_name, *targ_name; |
---|
| 4779 | + size_t local_len, targ_len; |
---|
1234 | 4780 | |
---|
1235 | | - insn_idx = prog->reloc_desc[i].insn_idx; |
---|
1236 | | - map_idx = prog->reloc_desc[i].map_idx; |
---|
| 4781 | + local_name = btf__name_by_offset(local_btf, |
---|
| 4782 | + local_type->name_off); |
---|
| 4783 | + targ_name = btf__name_by_offset(targ_btf, targ_type->name_off); |
---|
| 4784 | + local_len = bpf_core_essential_name_len(local_name); |
---|
| 4785 | + targ_len = bpf_core_essential_name_len(targ_name); |
---|
| 4786 | + /* one of them is anonymous or both w/ same flavor-less names */ |
---|
| 4787 | + return local_len == 0 || targ_len == 0 || |
---|
| 4788 | + (local_len == targ_len && |
---|
| 4789 | + strncmp(local_name, targ_name, local_len) == 0); |
---|
| 4790 | + } |
---|
| 4791 | + case BTF_KIND_INT: |
---|
| 4792 | + /* just reject deprecated bitfield-like integers; all other |
---|
| 4793 | + * integers are by default compatible between each other |
---|
| 4794 | + */ |
---|
| 4795 | + return btf_int_offset(local_type) == 0 && |
---|
| 4796 | + btf_int_offset(targ_type) == 0; |
---|
| 4797 | + case BTF_KIND_ARRAY: |
---|
| 4798 | + local_id = btf_array(local_type)->type; |
---|
| 4799 | + targ_id = btf_array(targ_type)->type; |
---|
| 4800 | + goto recur; |
---|
| 4801 | + default: |
---|
| 4802 | + pr_warn("unexpected kind %d relocated, local [%d], target [%d]\n", |
---|
| 4803 | + btf_kind(local_type), local_id, targ_id); |
---|
| 4804 | + return 0; |
---|
| 4805 | + } |
---|
| 4806 | +} |
---|
1237 | 4807 | |
---|
1238 | | - if (insn_idx >= (int)prog->insns_cnt) { |
---|
1239 | | - pr_warning("relocation out of range: '%s'\n", |
---|
1240 | | - prog->section_name); |
---|
1241 | | - return -LIBBPF_ERRNO__RELOC; |
---|
| 4808 | +/* |
---|
| 4809 | + * Given single high-level named field accessor in local type, find |
---|
| 4810 | + * corresponding high-level accessor for a target type. Along the way, |
---|
| 4811 | + * maintain low-level spec for target as well. Also keep updating target |
---|
| 4812 | + * bit offset. |
---|
| 4813 | + * |
---|
| 4814 | + * Searching is performed through recursive exhaustive enumeration of all |
---|
| 4815 | + * fields of a struct/union. If there are any anonymous (embedded) |
---|
| 4816 | + * structs/unions, they are recursively searched as well. If field with |
---|
| 4817 | + * desired name is found, check compatibility between local and target types, |
---|
| 4818 | + * before returning result. |
---|
| 4819 | + * |
---|
| 4820 | + * 1 is returned, if field is found. |
---|
| 4821 | + * 0 is returned if no compatible field is found. |
---|
| 4822 | + * <0 is returned on error. |
---|
| 4823 | + */ |
---|
| 4824 | +static int bpf_core_match_member(const struct btf *local_btf, |
---|
| 4825 | + const struct bpf_core_accessor *local_acc, |
---|
| 4826 | + const struct btf *targ_btf, |
---|
| 4827 | + __u32 targ_id, |
---|
| 4828 | + struct bpf_core_spec *spec, |
---|
| 4829 | + __u32 *next_targ_id) |
---|
| 4830 | +{ |
---|
| 4831 | + const struct btf_type *local_type, *targ_type; |
---|
| 4832 | + const struct btf_member *local_member, *m; |
---|
| 4833 | + const char *local_name, *targ_name; |
---|
| 4834 | + __u32 local_id; |
---|
| 4835 | + int i, n, found; |
---|
| 4836 | + |
---|
| 4837 | + targ_type = skip_mods_and_typedefs(targ_btf, targ_id, &targ_id); |
---|
| 4838 | + if (!targ_type) |
---|
| 4839 | + return -EINVAL; |
---|
| 4840 | + if (!btf_is_composite(targ_type)) |
---|
| 4841 | + return 0; |
---|
| 4842 | + |
---|
| 4843 | + local_id = local_acc->type_id; |
---|
| 4844 | + local_type = btf__type_by_id(local_btf, local_id); |
---|
| 4845 | + local_member = btf_members(local_type) + local_acc->idx; |
---|
| 4846 | + local_name = btf__name_by_offset(local_btf, local_member->name_off); |
---|
| 4847 | + |
---|
| 4848 | + n = btf_vlen(targ_type); |
---|
| 4849 | + m = btf_members(targ_type); |
---|
| 4850 | + for (i = 0; i < n; i++, m++) { |
---|
| 4851 | + __u32 bit_offset; |
---|
| 4852 | + |
---|
| 4853 | + bit_offset = btf_member_bit_offset(targ_type, i); |
---|
| 4854 | + |
---|
| 4855 | + /* too deep struct/union/array nesting */ |
---|
| 4856 | + if (spec->raw_len == BPF_CORE_SPEC_MAX_LEN) |
---|
| 4857 | + return -E2BIG; |
---|
| 4858 | + |
---|
| 4859 | + /* speculate this member will be the good one */ |
---|
| 4860 | + spec->bit_offset += bit_offset; |
---|
| 4861 | + spec->raw_spec[spec->raw_len++] = i; |
---|
| 4862 | + |
---|
| 4863 | + targ_name = btf__name_by_offset(targ_btf, m->name_off); |
---|
| 4864 | + if (str_is_empty(targ_name)) { |
---|
| 4865 | + /* embedded struct/union, we need to go deeper */ |
---|
| 4866 | + found = bpf_core_match_member(local_btf, local_acc, |
---|
| 4867 | + targ_btf, m->type, |
---|
| 4868 | + spec, next_targ_id); |
---|
| 4869 | + if (found) /* either found or error */ |
---|
| 4870 | + return found; |
---|
| 4871 | + } else if (strcmp(local_name, targ_name) == 0) { |
---|
| 4872 | + /* matching named field */ |
---|
| 4873 | + struct bpf_core_accessor *targ_acc; |
---|
| 4874 | + |
---|
| 4875 | + targ_acc = &spec->spec[spec->len++]; |
---|
| 4876 | + targ_acc->type_id = targ_id; |
---|
| 4877 | + targ_acc->idx = i; |
---|
| 4878 | + targ_acc->name = targ_name; |
---|
| 4879 | + |
---|
| 4880 | + *next_targ_id = m->type; |
---|
| 4881 | + found = bpf_core_fields_are_compat(local_btf, |
---|
| 4882 | + local_member->type, |
---|
| 4883 | + targ_btf, m->type); |
---|
| 4884 | + if (!found) |
---|
| 4885 | + spec->len--; /* pop accessor */ |
---|
| 4886 | + return found; |
---|
| 4887 | + } |
---|
| 4888 | + /* member turned out not to be what we looked for */ |
---|
| 4889 | + spec->bit_offset -= bit_offset; |
---|
| 4890 | + spec->raw_len--; |
---|
| 4891 | + } |
---|
| 4892 | + |
---|
| 4893 | + return 0; |
---|
| 4894 | +} |
---|
| 4895 | + |
---|
| 4896 | +/* Check local and target types for compatibility. This check is used for |
---|
| 4897 | + * type-based CO-RE relocations and follow slightly different rules than |
---|
| 4898 | + * field-based relocations. This function assumes that root types were already |
---|
| 4899 | + * checked for name match. Beyond that initial root-level name check, names |
---|
| 4900 | + * are completely ignored. Compatibility rules are as follows: |
---|
| 4901 | + * - any two STRUCTs/UNIONs/FWDs/ENUMs/INTs are considered compatible, but |
---|
| 4902 | + * kind should match for local and target types (i.e., STRUCT is not |
---|
| 4903 | + * compatible with UNION); |
---|
| 4904 | + * - for ENUMs, the size is ignored; |
---|
| 4905 | + * - for INT, size and signedness are ignored; |
---|
| 4906 | + * - for ARRAY, dimensionality is ignored, element types are checked for |
---|
| 4907 | + * compatibility recursively; |
---|
| 4908 | + * - CONST/VOLATILE/RESTRICT modifiers are ignored; |
---|
| 4909 | + * - TYPEDEFs/PTRs are compatible if types they pointing to are compatible; |
---|
| 4910 | + * - FUNC_PROTOs are compatible if they have compatible signature: same |
---|
| 4911 | + * number of input args and compatible return and argument types. |
---|
| 4912 | + * These rules are not set in stone and probably will be adjusted as we get |
---|
| 4913 | + * more experience with using BPF CO-RE relocations. |
---|
| 4914 | + */ |
---|
| 4915 | +static int bpf_core_types_are_compat(const struct btf *local_btf, __u32 local_id, |
---|
| 4916 | + const struct btf *targ_btf, __u32 targ_id) |
---|
| 4917 | +{ |
---|
| 4918 | + const struct btf_type *local_type, *targ_type; |
---|
| 4919 | + int depth = 32; /* max recursion depth */ |
---|
| 4920 | + |
---|
| 4921 | + /* caller made sure that names match (ignoring flavor suffix) */ |
---|
| 4922 | + local_type = btf__type_by_id(local_btf, local_id); |
---|
| 4923 | + targ_type = btf__type_by_id(targ_btf, targ_id); |
---|
| 4924 | + if (btf_kind(local_type) != btf_kind(targ_type)) |
---|
| 4925 | + return 0; |
---|
| 4926 | + |
---|
| 4927 | +recur: |
---|
| 4928 | + depth--; |
---|
| 4929 | + if (depth < 0) |
---|
| 4930 | + return -EINVAL; |
---|
| 4931 | + |
---|
| 4932 | + local_type = skip_mods_and_typedefs(local_btf, local_id, &local_id); |
---|
| 4933 | + targ_type = skip_mods_and_typedefs(targ_btf, targ_id, &targ_id); |
---|
| 4934 | + if (!local_type || !targ_type) |
---|
| 4935 | + return -EINVAL; |
---|
| 4936 | + |
---|
| 4937 | + if (btf_kind(local_type) != btf_kind(targ_type)) |
---|
| 4938 | + return 0; |
---|
| 4939 | + |
---|
| 4940 | + switch (btf_kind(local_type)) { |
---|
| 4941 | + case BTF_KIND_UNKN: |
---|
| 4942 | + case BTF_KIND_STRUCT: |
---|
| 4943 | + case BTF_KIND_UNION: |
---|
| 4944 | + case BTF_KIND_ENUM: |
---|
| 4945 | + case BTF_KIND_FWD: |
---|
| 4946 | + return 1; |
---|
| 4947 | + case BTF_KIND_INT: |
---|
| 4948 | + /* just reject deprecated bitfield-like integers; all other |
---|
| 4949 | + * integers are by default compatible between each other |
---|
| 4950 | + */ |
---|
| 4951 | + return btf_int_offset(local_type) == 0 && btf_int_offset(targ_type) == 0; |
---|
| 4952 | + case BTF_KIND_PTR: |
---|
| 4953 | + local_id = local_type->type; |
---|
| 4954 | + targ_id = targ_type->type; |
---|
| 4955 | + goto recur; |
---|
| 4956 | + case BTF_KIND_ARRAY: |
---|
| 4957 | + local_id = btf_array(local_type)->type; |
---|
| 4958 | + targ_id = btf_array(targ_type)->type; |
---|
| 4959 | + goto recur; |
---|
| 4960 | + case BTF_KIND_FUNC_PROTO: { |
---|
| 4961 | + struct btf_param *local_p = btf_params(local_type); |
---|
| 4962 | + struct btf_param *targ_p = btf_params(targ_type); |
---|
| 4963 | + __u16 local_vlen = btf_vlen(local_type); |
---|
| 4964 | + __u16 targ_vlen = btf_vlen(targ_type); |
---|
| 4965 | + int i, err; |
---|
| 4966 | + |
---|
| 4967 | + if (local_vlen != targ_vlen) |
---|
| 4968 | + return 0; |
---|
| 4969 | + |
---|
| 4970 | + for (i = 0; i < local_vlen; i++, local_p++, targ_p++) { |
---|
| 4971 | + skip_mods_and_typedefs(local_btf, local_p->type, &local_id); |
---|
| 4972 | + skip_mods_and_typedefs(targ_btf, targ_p->type, &targ_id); |
---|
| 4973 | + err = bpf_core_types_are_compat(local_btf, local_id, targ_btf, targ_id); |
---|
| 4974 | + if (err <= 0) |
---|
| 4975 | + return err; |
---|
| 4976 | + } |
---|
| 4977 | + |
---|
| 4978 | + /* tail recurse for return type check */ |
---|
| 4979 | + skip_mods_and_typedefs(local_btf, local_type->type, &local_id); |
---|
| 4980 | + skip_mods_and_typedefs(targ_btf, targ_type->type, &targ_id); |
---|
| 4981 | + goto recur; |
---|
| 4982 | + } |
---|
| 4983 | + default: |
---|
| 4984 | + pr_warn("unexpected kind %s relocated, local [%d], target [%d]\n", |
---|
| 4985 | + btf_kind_str(local_type), local_id, targ_id); |
---|
| 4986 | + return 0; |
---|
| 4987 | + } |
---|
| 4988 | +} |
---|
| 4989 | + |
---|
| 4990 | +/* |
---|
| 4991 | + * Try to match local spec to a target type and, if successful, produce full |
---|
| 4992 | + * target spec (high-level, low-level + bit offset). |
---|
| 4993 | + */ |
---|
| 4994 | +static int bpf_core_spec_match(struct bpf_core_spec *local_spec, |
---|
| 4995 | + const struct btf *targ_btf, __u32 targ_id, |
---|
| 4996 | + struct bpf_core_spec *targ_spec) |
---|
| 4997 | +{ |
---|
| 4998 | + const struct btf_type *targ_type; |
---|
| 4999 | + const struct bpf_core_accessor *local_acc; |
---|
| 5000 | + struct bpf_core_accessor *targ_acc; |
---|
| 5001 | + int i, sz, matched; |
---|
| 5002 | + |
---|
| 5003 | + memset(targ_spec, 0, sizeof(*targ_spec)); |
---|
| 5004 | + targ_spec->btf = targ_btf; |
---|
| 5005 | + targ_spec->root_type_id = targ_id; |
---|
| 5006 | + targ_spec->relo_kind = local_spec->relo_kind; |
---|
| 5007 | + |
---|
| 5008 | + if (core_relo_is_type_based(local_spec->relo_kind)) { |
---|
| 5009 | + return bpf_core_types_are_compat(local_spec->btf, |
---|
| 5010 | + local_spec->root_type_id, |
---|
| 5011 | + targ_btf, targ_id); |
---|
| 5012 | + } |
---|
| 5013 | + |
---|
| 5014 | + local_acc = &local_spec->spec[0]; |
---|
| 5015 | + targ_acc = &targ_spec->spec[0]; |
---|
| 5016 | + |
---|
| 5017 | + if (core_relo_is_enumval_based(local_spec->relo_kind)) { |
---|
| 5018 | + size_t local_essent_len, targ_essent_len; |
---|
| 5019 | + const struct btf_enum *e; |
---|
| 5020 | + const char *targ_name; |
---|
| 5021 | + |
---|
| 5022 | + /* has to resolve to an enum */ |
---|
| 5023 | + targ_type = skip_mods_and_typedefs(targ_spec->btf, targ_id, &targ_id); |
---|
| 5024 | + if (!btf_is_enum(targ_type)) |
---|
| 5025 | + return 0; |
---|
| 5026 | + |
---|
| 5027 | + local_essent_len = bpf_core_essential_name_len(local_acc->name); |
---|
| 5028 | + |
---|
| 5029 | + for (i = 0, e = btf_enum(targ_type); i < btf_vlen(targ_type); i++, e++) { |
---|
| 5030 | + targ_name = btf__name_by_offset(targ_spec->btf, e->name_off); |
---|
| 5031 | + targ_essent_len = bpf_core_essential_name_len(targ_name); |
---|
| 5032 | + if (targ_essent_len != local_essent_len) |
---|
| 5033 | + continue; |
---|
| 5034 | + if (strncmp(local_acc->name, targ_name, local_essent_len) == 0) { |
---|
| 5035 | + targ_acc->type_id = targ_id; |
---|
| 5036 | + targ_acc->idx = i; |
---|
| 5037 | + targ_acc->name = targ_name; |
---|
| 5038 | + targ_spec->len++; |
---|
| 5039 | + targ_spec->raw_spec[targ_spec->raw_len] = targ_acc->idx; |
---|
| 5040 | + targ_spec->raw_len++; |
---|
| 5041 | + return 1; |
---|
1242 | 5042 | } |
---|
1243 | | - insns[insn_idx].src_reg = BPF_PSEUDO_MAP_FD; |
---|
1244 | | - insns[insn_idx].imm = obj->maps[map_idx].fd; |
---|
| 5043 | + } |
---|
| 5044 | + return 0; |
---|
| 5045 | + } |
---|
| 5046 | + |
---|
| 5047 | + if (!core_relo_is_field_based(local_spec->relo_kind)) |
---|
| 5048 | + return -EINVAL; |
---|
| 5049 | + |
---|
| 5050 | + for (i = 0; i < local_spec->len; i++, local_acc++, targ_acc++) { |
---|
| 5051 | + targ_type = skip_mods_and_typedefs(targ_spec->btf, targ_id, |
---|
| 5052 | + &targ_id); |
---|
| 5053 | + if (!targ_type) |
---|
| 5054 | + return -EINVAL; |
---|
| 5055 | + |
---|
| 5056 | + if (local_acc->name) { |
---|
| 5057 | + matched = bpf_core_match_member(local_spec->btf, |
---|
| 5058 | + local_acc, |
---|
| 5059 | + targ_btf, targ_id, |
---|
| 5060 | + targ_spec, &targ_id); |
---|
| 5061 | + if (matched <= 0) |
---|
| 5062 | + return matched; |
---|
1245 | 5063 | } else { |
---|
1246 | | - err = bpf_program__reloc_text(prog, obj, |
---|
1247 | | - &prog->reloc_desc[i]); |
---|
| 5064 | + /* for i=0, targ_id is already treated as array element |
---|
| 5065 | + * type (because it's the original struct), for others |
---|
| 5066 | + * we should find array element type first |
---|
| 5067 | + */ |
---|
| 5068 | + if (i > 0) { |
---|
| 5069 | + const struct btf_array *a; |
---|
| 5070 | + bool flex; |
---|
| 5071 | + |
---|
| 5072 | + if (!btf_is_array(targ_type)) |
---|
| 5073 | + return 0; |
---|
| 5074 | + |
---|
| 5075 | + a = btf_array(targ_type); |
---|
| 5076 | + flex = is_flex_arr(targ_btf, targ_acc - 1, a); |
---|
| 5077 | + if (!flex && local_acc->idx >= a->nelems) |
---|
| 5078 | + return 0; |
---|
| 5079 | + if (!skip_mods_and_typedefs(targ_btf, a->type, |
---|
| 5080 | + &targ_id)) |
---|
| 5081 | + return -EINVAL; |
---|
| 5082 | + } |
---|
| 5083 | + |
---|
| 5084 | + /* too deep struct/union/array nesting */ |
---|
| 5085 | + if (targ_spec->raw_len == BPF_CORE_SPEC_MAX_LEN) |
---|
| 5086 | + return -E2BIG; |
---|
| 5087 | + |
---|
| 5088 | + targ_acc->type_id = targ_id; |
---|
| 5089 | + targ_acc->idx = local_acc->idx; |
---|
| 5090 | + targ_acc->name = NULL; |
---|
| 5091 | + targ_spec->len++; |
---|
| 5092 | + targ_spec->raw_spec[targ_spec->raw_len] = targ_acc->idx; |
---|
| 5093 | + targ_spec->raw_len++; |
---|
| 5094 | + |
---|
| 5095 | + sz = btf__resolve_size(targ_btf, targ_id); |
---|
| 5096 | + if (sz < 0) |
---|
| 5097 | + return sz; |
---|
| 5098 | + targ_spec->bit_offset += local_acc->idx * sz * 8; |
---|
| 5099 | + } |
---|
| 5100 | + } |
---|
| 5101 | + |
---|
| 5102 | + return 1; |
---|
| 5103 | +} |
---|
| 5104 | + |
---|
| 5105 | +static int bpf_core_calc_field_relo(const struct bpf_program *prog, |
---|
| 5106 | + const struct bpf_core_relo *relo, |
---|
| 5107 | + const struct bpf_core_spec *spec, |
---|
| 5108 | + __u32 *val, __u32 *field_sz, __u32 *type_id, |
---|
| 5109 | + bool *validate) |
---|
| 5110 | +{ |
---|
| 5111 | + const struct bpf_core_accessor *acc; |
---|
| 5112 | + const struct btf_type *t; |
---|
| 5113 | + __u32 byte_off, byte_sz, bit_off, bit_sz, field_type_id; |
---|
| 5114 | + const struct btf_member *m; |
---|
| 5115 | + const struct btf_type *mt; |
---|
| 5116 | + bool bitfield; |
---|
| 5117 | + __s64 sz; |
---|
| 5118 | + |
---|
| 5119 | + *field_sz = 0; |
---|
| 5120 | + |
---|
| 5121 | + if (relo->kind == BPF_FIELD_EXISTS) { |
---|
| 5122 | + *val = spec ? 1 : 0; |
---|
| 5123 | + return 0; |
---|
| 5124 | + } |
---|
| 5125 | + |
---|
| 5126 | + if (!spec) |
---|
| 5127 | + return -EUCLEAN; /* request instruction poisoning */ |
---|
| 5128 | + |
---|
| 5129 | + acc = &spec->spec[spec->len - 1]; |
---|
| 5130 | + t = btf__type_by_id(spec->btf, acc->type_id); |
---|
| 5131 | + |
---|
| 5132 | + /* a[n] accessor needs special handling */ |
---|
| 5133 | + if (!acc->name) { |
---|
| 5134 | + if (relo->kind == BPF_FIELD_BYTE_OFFSET) { |
---|
| 5135 | + *val = spec->bit_offset / 8; |
---|
| 5136 | + /* remember field size for load/store mem size */ |
---|
| 5137 | + sz = btf__resolve_size(spec->btf, acc->type_id); |
---|
| 5138 | + if (sz < 0) |
---|
| 5139 | + return -EINVAL; |
---|
| 5140 | + *field_sz = sz; |
---|
| 5141 | + *type_id = acc->type_id; |
---|
| 5142 | + } else if (relo->kind == BPF_FIELD_BYTE_SIZE) { |
---|
| 5143 | + sz = btf__resolve_size(spec->btf, acc->type_id); |
---|
| 5144 | + if (sz < 0) |
---|
| 5145 | + return -EINVAL; |
---|
| 5146 | + *val = sz; |
---|
| 5147 | + } else { |
---|
| 5148 | + pr_warn("prog '%s': relo %d at insn #%d can't be applied to array access\n", |
---|
| 5149 | + prog->name, relo->kind, relo->insn_off / 8); |
---|
| 5150 | + return -EINVAL; |
---|
| 5151 | + } |
---|
| 5152 | + if (validate) |
---|
| 5153 | + *validate = true; |
---|
| 5154 | + return 0; |
---|
| 5155 | + } |
---|
| 5156 | + |
---|
| 5157 | + m = btf_members(t) + acc->idx; |
---|
| 5158 | + mt = skip_mods_and_typedefs(spec->btf, m->type, &field_type_id); |
---|
| 5159 | + bit_off = spec->bit_offset; |
---|
| 5160 | + bit_sz = btf_member_bitfield_size(t, acc->idx); |
---|
| 5161 | + |
---|
| 5162 | + bitfield = bit_sz > 0; |
---|
| 5163 | + if (bitfield) { |
---|
| 5164 | + byte_sz = mt->size; |
---|
| 5165 | + byte_off = bit_off / 8 / byte_sz * byte_sz; |
---|
| 5166 | + /* figure out smallest int size necessary for bitfield load */ |
---|
| 5167 | + while (bit_off + bit_sz - byte_off * 8 > byte_sz * 8) { |
---|
| 5168 | + if (byte_sz >= 8) { |
---|
| 5169 | + /* bitfield can't be read with 64-bit read */ |
---|
| 5170 | + pr_warn("prog '%s': relo %d at insn #%d can't be satisfied for bitfield\n", |
---|
| 5171 | + prog->name, relo->kind, relo->insn_off / 8); |
---|
| 5172 | + return -E2BIG; |
---|
| 5173 | + } |
---|
| 5174 | + byte_sz *= 2; |
---|
| 5175 | + byte_off = bit_off / 8 / byte_sz * byte_sz; |
---|
| 5176 | + } |
---|
| 5177 | + } else { |
---|
| 5178 | + sz = btf__resolve_size(spec->btf, field_type_id); |
---|
| 5179 | + if (sz < 0) |
---|
| 5180 | + return -EINVAL; |
---|
| 5181 | + byte_sz = sz; |
---|
| 5182 | + byte_off = spec->bit_offset / 8; |
---|
| 5183 | + bit_sz = byte_sz * 8; |
---|
| 5184 | + } |
---|
| 5185 | + |
---|
| 5186 | + /* for bitfields, all the relocatable aspects are ambiguous and we |
---|
| 5187 | + * might disagree with compiler, so turn off validation of expected |
---|
| 5188 | + * value, except for signedness |
---|
| 5189 | + */ |
---|
| 5190 | + if (validate) |
---|
| 5191 | + *validate = !bitfield; |
---|
| 5192 | + |
---|
| 5193 | + switch (relo->kind) { |
---|
| 5194 | + case BPF_FIELD_BYTE_OFFSET: |
---|
| 5195 | + *val = byte_off; |
---|
| 5196 | + if (!bitfield) { |
---|
| 5197 | + *field_sz = byte_sz; |
---|
| 5198 | + *type_id = field_type_id; |
---|
| 5199 | + } |
---|
| 5200 | + break; |
---|
| 5201 | + case BPF_FIELD_BYTE_SIZE: |
---|
| 5202 | + *val = byte_sz; |
---|
| 5203 | + break; |
---|
| 5204 | + case BPF_FIELD_SIGNED: |
---|
| 5205 | + /* enums will be assumed unsigned */ |
---|
| 5206 | + *val = btf_is_enum(mt) || |
---|
| 5207 | + (btf_int_encoding(mt) & BTF_INT_SIGNED); |
---|
| 5208 | + if (validate) |
---|
| 5209 | + *validate = true; /* signedness is never ambiguous */ |
---|
| 5210 | + break; |
---|
| 5211 | + case BPF_FIELD_LSHIFT_U64: |
---|
| 5212 | +#if __BYTE_ORDER == __LITTLE_ENDIAN |
---|
| 5213 | + *val = 64 - (bit_off + bit_sz - byte_off * 8); |
---|
| 5214 | +#else |
---|
| 5215 | + *val = (8 - byte_sz) * 8 + (bit_off - byte_off * 8); |
---|
| 5216 | +#endif |
---|
| 5217 | + break; |
---|
| 5218 | + case BPF_FIELD_RSHIFT_U64: |
---|
| 5219 | + *val = 64 - bit_sz; |
---|
| 5220 | + if (validate) |
---|
| 5221 | + *validate = true; /* right shift is never ambiguous */ |
---|
| 5222 | + break; |
---|
| 5223 | + case BPF_FIELD_EXISTS: |
---|
| 5224 | + default: |
---|
| 5225 | + return -EOPNOTSUPP; |
---|
| 5226 | + } |
---|
| 5227 | + |
---|
| 5228 | + return 0; |
---|
| 5229 | +} |
---|
| 5230 | + |
---|
| 5231 | +static int bpf_core_calc_type_relo(const struct bpf_core_relo *relo, |
---|
| 5232 | + const struct bpf_core_spec *spec, |
---|
| 5233 | + __u32 *val) |
---|
| 5234 | +{ |
---|
| 5235 | + __s64 sz; |
---|
| 5236 | + |
---|
| 5237 | + /* type-based relos return zero when target type is not found */ |
---|
| 5238 | + if (!spec) { |
---|
| 5239 | + *val = 0; |
---|
| 5240 | + return 0; |
---|
| 5241 | + } |
---|
| 5242 | + |
---|
| 5243 | + switch (relo->kind) { |
---|
| 5244 | + case BPF_TYPE_ID_TARGET: |
---|
| 5245 | + *val = spec->root_type_id; |
---|
| 5246 | + break; |
---|
| 5247 | + case BPF_TYPE_EXISTS: |
---|
| 5248 | + *val = 1; |
---|
| 5249 | + break; |
---|
| 5250 | + case BPF_TYPE_SIZE: |
---|
| 5251 | + sz = btf__resolve_size(spec->btf, spec->root_type_id); |
---|
| 5252 | + if (sz < 0) |
---|
| 5253 | + return -EINVAL; |
---|
| 5254 | + *val = sz; |
---|
| 5255 | + break; |
---|
| 5256 | + case BPF_TYPE_ID_LOCAL: |
---|
| 5257 | + /* BPF_TYPE_ID_LOCAL is handled specially and shouldn't get here */ |
---|
| 5258 | + default: |
---|
| 5259 | + return -EOPNOTSUPP; |
---|
| 5260 | + } |
---|
| 5261 | + |
---|
| 5262 | + return 0; |
---|
| 5263 | +} |
---|
| 5264 | + |
---|
| 5265 | +static int bpf_core_calc_enumval_relo(const struct bpf_core_relo *relo, |
---|
| 5266 | + const struct bpf_core_spec *spec, |
---|
| 5267 | + __u32 *val) |
---|
| 5268 | +{ |
---|
| 5269 | + const struct btf_type *t; |
---|
| 5270 | + const struct btf_enum *e; |
---|
| 5271 | + |
---|
| 5272 | + switch (relo->kind) { |
---|
| 5273 | + case BPF_ENUMVAL_EXISTS: |
---|
| 5274 | + *val = spec ? 1 : 0; |
---|
| 5275 | + break; |
---|
| 5276 | + case BPF_ENUMVAL_VALUE: |
---|
| 5277 | + if (!spec) |
---|
| 5278 | + return -EUCLEAN; /* request instruction poisoning */ |
---|
| 5279 | + t = btf__type_by_id(spec->btf, spec->spec[0].type_id); |
---|
| 5280 | + e = btf_enum(t) + spec->spec[0].idx; |
---|
| 5281 | + *val = e->val; |
---|
| 5282 | + break; |
---|
| 5283 | + default: |
---|
| 5284 | + return -EOPNOTSUPP; |
---|
| 5285 | + } |
---|
| 5286 | + |
---|
| 5287 | + return 0; |
---|
| 5288 | +} |
---|
| 5289 | + |
---|
| 5290 | +struct bpf_core_relo_res |
---|
| 5291 | +{ |
---|
| 5292 | + /* expected value in the instruction, unless validate == false */ |
---|
| 5293 | + __u32 orig_val; |
---|
| 5294 | + /* new value that needs to be patched up to */ |
---|
| 5295 | + __u32 new_val; |
---|
| 5296 | + /* relocation unsuccessful, poison instruction, but don't fail load */ |
---|
| 5297 | + bool poison; |
---|
| 5298 | + /* some relocations can't be validated against orig_val */ |
---|
| 5299 | + bool validate; |
---|
| 5300 | + /* for field byte offset relocations or the forms: |
---|
| 5301 | + * *(T *)(rX + <off>) = rY |
---|
| 5302 | + * rX = *(T *)(rY + <off>), |
---|
| 5303 | + * we remember original and resolved field size to adjust direct |
---|
| 5304 | + * memory loads of pointers and integers; this is necessary for 32-bit |
---|
| 5305 | + * host kernel architectures, but also allows to automatically |
---|
| 5306 | + * relocate fields that were resized from, e.g., u32 to u64, etc. |
---|
| 5307 | + */ |
---|
| 5308 | + bool fail_memsz_adjust; |
---|
| 5309 | + __u32 orig_sz; |
---|
| 5310 | + __u32 orig_type_id; |
---|
| 5311 | + __u32 new_sz; |
---|
| 5312 | + __u32 new_type_id; |
---|
| 5313 | +}; |
---|
| 5314 | + |
---|
| 5315 | +/* Calculate original and target relocation values, given local and target |
---|
| 5316 | + * specs and relocation kind. These values are calculated for each candidate. |
---|
| 5317 | + * If there are multiple candidates, resulting values should all be consistent |
---|
| 5318 | + * with each other. Otherwise, libbpf will refuse to proceed due to ambiguity. |
---|
| 5319 | + * If instruction has to be poisoned, *poison will be set to true. |
---|
| 5320 | + */ |
---|
| 5321 | +static int bpf_core_calc_relo(const struct bpf_program *prog, |
---|
| 5322 | + const struct bpf_core_relo *relo, |
---|
| 5323 | + int relo_idx, |
---|
| 5324 | + const struct bpf_core_spec *local_spec, |
---|
| 5325 | + const struct bpf_core_spec *targ_spec, |
---|
| 5326 | + struct bpf_core_relo_res *res) |
---|
| 5327 | +{ |
---|
| 5328 | + int err = -EOPNOTSUPP; |
---|
| 5329 | + |
---|
| 5330 | + res->orig_val = 0; |
---|
| 5331 | + res->new_val = 0; |
---|
| 5332 | + res->poison = false; |
---|
| 5333 | + res->validate = true; |
---|
| 5334 | + res->fail_memsz_adjust = false; |
---|
| 5335 | + res->orig_sz = res->new_sz = 0; |
---|
| 5336 | + res->orig_type_id = res->new_type_id = 0; |
---|
| 5337 | + |
---|
| 5338 | + if (core_relo_is_field_based(relo->kind)) { |
---|
| 5339 | + err = bpf_core_calc_field_relo(prog, relo, local_spec, |
---|
| 5340 | + &res->orig_val, &res->orig_sz, |
---|
| 5341 | + &res->orig_type_id, &res->validate); |
---|
| 5342 | + err = err ?: bpf_core_calc_field_relo(prog, relo, targ_spec, |
---|
| 5343 | + &res->new_val, &res->new_sz, |
---|
| 5344 | + &res->new_type_id, NULL); |
---|
| 5345 | + if (err) |
---|
| 5346 | + goto done; |
---|
| 5347 | + /* Validate if it's safe to adjust load/store memory size. |
---|
| 5348 | + * Adjustments are performed only if original and new memory |
---|
| 5349 | + * sizes differ. |
---|
| 5350 | + */ |
---|
| 5351 | + res->fail_memsz_adjust = false; |
---|
| 5352 | + if (res->orig_sz != res->new_sz) { |
---|
| 5353 | + const struct btf_type *orig_t, *new_t; |
---|
| 5354 | + |
---|
| 5355 | + orig_t = btf__type_by_id(local_spec->btf, res->orig_type_id); |
---|
| 5356 | + new_t = btf__type_by_id(targ_spec->btf, res->new_type_id); |
---|
| 5357 | + |
---|
| 5358 | + /* There are two use cases in which it's safe to |
---|
| 5359 | + * adjust load/store's mem size: |
---|
| 5360 | + * - reading a 32-bit kernel pointer, while on BPF |
---|
| 5361 | + * size pointers are always 64-bit; in this case |
---|
| 5362 | + * it's safe to "downsize" instruction size due to |
---|
| 5363 | + * pointer being treated as unsigned integer with |
---|
| 5364 | + * zero-extended upper 32-bits; |
---|
| 5365 | + * - reading unsigned integers, again due to |
---|
| 5366 | + * zero-extension is preserving the value correctly. |
---|
| 5367 | + * |
---|
| 5368 | + * In all other cases it's incorrect to attempt to |
---|
| 5369 | + * load/store field because read value will be |
---|
| 5370 | + * incorrect, so we poison relocated instruction. |
---|
| 5371 | + */ |
---|
| 5372 | + if (btf_is_ptr(orig_t) && btf_is_ptr(new_t)) |
---|
| 5373 | + goto done; |
---|
| 5374 | + if (btf_is_int(orig_t) && btf_is_int(new_t) && |
---|
| 5375 | + btf_int_encoding(orig_t) != BTF_INT_SIGNED && |
---|
| 5376 | + btf_int_encoding(new_t) != BTF_INT_SIGNED) |
---|
| 5377 | + goto done; |
---|
| 5378 | + |
---|
| 5379 | + /* mark as invalid mem size adjustment, but this will |
---|
| 5380 | + * only be checked for LDX/STX/ST insns |
---|
| 5381 | + */ |
---|
| 5382 | + res->fail_memsz_adjust = true; |
---|
| 5383 | + } |
---|
| 5384 | + } else if (core_relo_is_type_based(relo->kind)) { |
---|
| 5385 | + err = bpf_core_calc_type_relo(relo, local_spec, &res->orig_val); |
---|
| 5386 | + err = err ?: bpf_core_calc_type_relo(relo, targ_spec, &res->new_val); |
---|
| 5387 | + } else if (core_relo_is_enumval_based(relo->kind)) { |
---|
| 5388 | + err = bpf_core_calc_enumval_relo(relo, local_spec, &res->orig_val); |
---|
| 5389 | + err = err ?: bpf_core_calc_enumval_relo(relo, targ_spec, &res->new_val); |
---|
| 5390 | + } |
---|
| 5391 | + |
---|
| 5392 | +done: |
---|
| 5393 | + if (err == -EUCLEAN) { |
---|
| 5394 | + /* EUCLEAN is used to signal instruction poisoning request */ |
---|
| 5395 | + res->poison = true; |
---|
| 5396 | + err = 0; |
---|
| 5397 | + } else if (err == -EOPNOTSUPP) { |
---|
| 5398 | + /* EOPNOTSUPP means unknown/unsupported relocation */ |
---|
| 5399 | + pr_warn("prog '%s': relo #%d: unrecognized CO-RE relocation %s (%d) at insn #%d\n", |
---|
| 5400 | + prog->name, relo_idx, core_relo_kind_str(relo->kind), |
---|
| 5401 | + relo->kind, relo->insn_off / 8); |
---|
| 5402 | + } |
---|
| 5403 | + |
---|
| 5404 | + return err; |
---|
| 5405 | +} |
---|
| 5406 | + |
---|
| 5407 | +/* |
---|
| 5408 | + * Turn instruction for which CO_RE relocation failed into invalid one with |
---|
| 5409 | + * distinct signature. |
---|
| 5410 | + */ |
---|
| 5411 | +static void bpf_core_poison_insn(struct bpf_program *prog, int relo_idx, |
---|
| 5412 | + int insn_idx, struct bpf_insn *insn) |
---|
| 5413 | +{ |
---|
| 5414 | + pr_debug("prog '%s': relo #%d: substituting insn #%d w/ invalid insn\n", |
---|
| 5415 | + prog->name, relo_idx, insn_idx); |
---|
| 5416 | + insn->code = BPF_JMP | BPF_CALL; |
---|
| 5417 | + insn->dst_reg = 0; |
---|
| 5418 | + insn->src_reg = 0; |
---|
| 5419 | + insn->off = 0; |
---|
| 5420 | + /* if this instruction is reachable (not a dead code), |
---|
| 5421 | + * verifier will complain with the following message: |
---|
| 5422 | + * invalid func unknown#195896080 |
---|
| 5423 | + */ |
---|
| 5424 | + insn->imm = 195896080; /* => 0xbad2310 => "bad relo" */ |
---|
| 5425 | +} |
---|
| 5426 | + |
---|
| 5427 | +static bool is_ldimm64(struct bpf_insn *insn) |
---|
| 5428 | +{ |
---|
| 5429 | + return insn->code == (BPF_LD | BPF_IMM | BPF_DW); |
---|
| 5430 | +} |
---|
| 5431 | + |
---|
| 5432 | +static int insn_bpf_size_to_bytes(struct bpf_insn *insn) |
---|
| 5433 | +{ |
---|
| 5434 | + switch (BPF_SIZE(insn->code)) { |
---|
| 5435 | + case BPF_DW: return 8; |
---|
| 5436 | + case BPF_W: return 4; |
---|
| 5437 | + case BPF_H: return 2; |
---|
| 5438 | + case BPF_B: return 1; |
---|
| 5439 | + default: return -1; |
---|
| 5440 | + } |
---|
| 5441 | +} |
---|
| 5442 | + |
---|
| 5443 | +static int insn_bytes_to_bpf_size(__u32 sz) |
---|
| 5444 | +{ |
---|
| 5445 | + switch (sz) { |
---|
| 5446 | + case 8: return BPF_DW; |
---|
| 5447 | + case 4: return BPF_W; |
---|
| 5448 | + case 2: return BPF_H; |
---|
| 5449 | + case 1: return BPF_B; |
---|
| 5450 | + default: return -1; |
---|
| 5451 | + } |
---|
| 5452 | +} |
---|
| 5453 | + |
---|
| 5454 | +/* |
---|
| 5455 | + * Patch relocatable BPF instruction. |
---|
| 5456 | + * |
---|
| 5457 | + * Patched value is determined by relocation kind and target specification. |
---|
| 5458 | + * For existence relocations target spec will be NULL if field/type is not found. |
---|
| 5459 | + * Expected insn->imm value is determined using relocation kind and local |
---|
| 5460 | + * spec, and is checked before patching instruction. If actual insn->imm value |
---|
| 5461 | + * is wrong, bail out with error. |
---|
| 5462 | + * |
---|
| 5463 | + * Currently supported classes of BPF instruction are: |
---|
| 5464 | + * 1. rX = <imm> (assignment with immediate operand); |
---|
| 5465 | + * 2. rX += <imm> (arithmetic operations with immediate operand); |
---|
| 5466 | + * 3. rX = <imm64> (load with 64-bit immediate value); |
---|
| 5467 | + * 4. rX = *(T *)(rY + <off>), where T is one of {u8, u16, u32, u64}; |
---|
| 5468 | + * 5. *(T *)(rX + <off>) = rY, where T is one of {u8, u16, u32, u64}; |
---|
| 5469 | + * 6. *(T *)(rX + <off>) = <imm>, where T is one of {u8, u16, u32, u64}. |
---|
| 5470 | + */ |
---|
| 5471 | +static int bpf_core_patch_insn(struct bpf_program *prog, |
---|
| 5472 | + const struct bpf_core_relo *relo, |
---|
| 5473 | + int relo_idx, |
---|
| 5474 | + const struct bpf_core_relo_res *res) |
---|
| 5475 | +{ |
---|
| 5476 | + __u32 orig_val, new_val; |
---|
| 5477 | + struct bpf_insn *insn; |
---|
| 5478 | + int insn_idx; |
---|
| 5479 | + __u8 class; |
---|
| 5480 | + |
---|
| 5481 | + if (relo->insn_off % BPF_INSN_SZ) |
---|
| 5482 | + return -EINVAL; |
---|
| 5483 | + insn_idx = relo->insn_off / BPF_INSN_SZ; |
---|
| 5484 | + /* adjust insn_idx from section frame of reference to the local |
---|
| 5485 | + * program's frame of reference; (sub-)program code is not yet |
---|
| 5486 | + * relocated, so it's enough to just subtract in-section offset |
---|
| 5487 | + */ |
---|
| 5488 | + insn_idx = insn_idx - prog->sec_insn_off; |
---|
| 5489 | + insn = &prog->insns[insn_idx]; |
---|
| 5490 | + class = BPF_CLASS(insn->code); |
---|
| 5491 | + |
---|
| 5492 | + if (res->poison) { |
---|
| 5493 | +poison: |
---|
| 5494 | + /* poison second part of ldimm64 to avoid confusing error from |
---|
| 5495 | + * verifier about "unknown opcode 00" |
---|
| 5496 | + */ |
---|
| 5497 | + if (is_ldimm64(insn)) |
---|
| 5498 | + bpf_core_poison_insn(prog, relo_idx, insn_idx + 1, insn + 1); |
---|
| 5499 | + bpf_core_poison_insn(prog, relo_idx, insn_idx, insn); |
---|
| 5500 | + return 0; |
---|
| 5501 | + } |
---|
| 5502 | + |
---|
| 5503 | + orig_val = res->orig_val; |
---|
| 5504 | + new_val = res->new_val; |
---|
| 5505 | + |
---|
| 5506 | + switch (class) { |
---|
| 5507 | + case BPF_ALU: |
---|
| 5508 | + case BPF_ALU64: |
---|
| 5509 | + if (BPF_SRC(insn->code) != BPF_K) |
---|
| 5510 | + return -EINVAL; |
---|
| 5511 | + if (res->validate && insn->imm != orig_val) { |
---|
| 5512 | + pr_warn("prog '%s': relo #%d: unexpected insn #%d (ALU/ALU64) value: got %u, exp %u -> %u\n", |
---|
| 5513 | + prog->name, relo_idx, |
---|
| 5514 | + insn_idx, insn->imm, orig_val, new_val); |
---|
| 5515 | + return -EINVAL; |
---|
| 5516 | + } |
---|
| 5517 | + orig_val = insn->imm; |
---|
| 5518 | + insn->imm = new_val; |
---|
| 5519 | + pr_debug("prog '%s': relo #%d: patched insn #%d (ALU/ALU64) imm %u -> %u\n", |
---|
| 5520 | + prog->name, relo_idx, insn_idx, |
---|
| 5521 | + orig_val, new_val); |
---|
| 5522 | + break; |
---|
| 5523 | + case BPF_LDX: |
---|
| 5524 | + case BPF_ST: |
---|
| 5525 | + case BPF_STX: |
---|
| 5526 | + if (res->validate && insn->off != orig_val) { |
---|
| 5527 | + pr_warn("prog '%s': relo #%d: unexpected insn #%d (LDX/ST/STX) value: got %u, exp %u -> %u\n", |
---|
| 5528 | + prog->name, relo_idx, insn_idx, insn->off, orig_val, new_val); |
---|
| 5529 | + return -EINVAL; |
---|
| 5530 | + } |
---|
| 5531 | + if (new_val > SHRT_MAX) { |
---|
| 5532 | + pr_warn("prog '%s': relo #%d: insn #%d (LDX/ST/STX) value too big: %u\n", |
---|
| 5533 | + prog->name, relo_idx, insn_idx, new_val); |
---|
| 5534 | + return -ERANGE; |
---|
| 5535 | + } |
---|
| 5536 | + if (res->fail_memsz_adjust) { |
---|
| 5537 | + pr_warn("prog '%s': relo #%d: insn #%d (LDX/ST/STX) accesses field incorrectly. " |
---|
| 5538 | + "Make sure you are accessing pointers, unsigned integers, or fields of matching type and size.\n", |
---|
| 5539 | + prog->name, relo_idx, insn_idx); |
---|
| 5540 | + goto poison; |
---|
| 5541 | + } |
---|
| 5542 | + |
---|
| 5543 | + orig_val = insn->off; |
---|
| 5544 | + insn->off = new_val; |
---|
| 5545 | + pr_debug("prog '%s': relo #%d: patched insn #%d (LDX/ST/STX) off %u -> %u\n", |
---|
| 5546 | + prog->name, relo_idx, insn_idx, orig_val, new_val); |
---|
| 5547 | + |
---|
| 5548 | + if (res->new_sz != res->orig_sz) { |
---|
| 5549 | + int insn_bytes_sz, insn_bpf_sz; |
---|
| 5550 | + |
---|
| 5551 | + insn_bytes_sz = insn_bpf_size_to_bytes(insn); |
---|
| 5552 | + if (insn_bytes_sz != res->orig_sz) { |
---|
| 5553 | + pr_warn("prog '%s': relo #%d: insn #%d (LDX/ST/STX) unexpected mem size: got %d, exp %u\n", |
---|
| 5554 | + prog->name, relo_idx, insn_idx, insn_bytes_sz, res->orig_sz); |
---|
| 5555 | + return -EINVAL; |
---|
| 5556 | + } |
---|
| 5557 | + |
---|
| 5558 | + insn_bpf_sz = insn_bytes_to_bpf_size(res->new_sz); |
---|
| 5559 | + if (insn_bpf_sz < 0) { |
---|
| 5560 | + pr_warn("prog '%s': relo #%d: insn #%d (LDX/ST/STX) invalid new mem size: %u\n", |
---|
| 5561 | + prog->name, relo_idx, insn_idx, res->new_sz); |
---|
| 5562 | + return -EINVAL; |
---|
| 5563 | + } |
---|
| 5564 | + |
---|
| 5565 | + insn->code = BPF_MODE(insn->code) | insn_bpf_sz | BPF_CLASS(insn->code); |
---|
| 5566 | + pr_debug("prog '%s': relo #%d: patched insn #%d (LDX/ST/STX) mem_sz %u -> %u\n", |
---|
| 5567 | + prog->name, relo_idx, insn_idx, res->orig_sz, res->new_sz); |
---|
| 5568 | + } |
---|
| 5569 | + break; |
---|
| 5570 | + case BPF_LD: { |
---|
| 5571 | + __u64 imm; |
---|
| 5572 | + |
---|
| 5573 | + if (!is_ldimm64(insn) || |
---|
| 5574 | + insn[0].src_reg != 0 || insn[0].off != 0 || |
---|
| 5575 | + insn_idx + 1 >= prog->insns_cnt || |
---|
| 5576 | + insn[1].code != 0 || insn[1].dst_reg != 0 || |
---|
| 5577 | + insn[1].src_reg != 0 || insn[1].off != 0) { |
---|
| 5578 | + pr_warn("prog '%s': relo #%d: insn #%d (LDIMM64) has unexpected form\n", |
---|
| 5579 | + prog->name, relo_idx, insn_idx); |
---|
| 5580 | + return -EINVAL; |
---|
| 5581 | + } |
---|
| 5582 | + |
---|
| 5583 | + imm = insn[0].imm + ((__u64)insn[1].imm << 32); |
---|
| 5584 | + if (res->validate && imm != orig_val) { |
---|
| 5585 | + pr_warn("prog '%s': relo #%d: unexpected insn #%d (LDIMM64) value: got %llu, exp %u -> %u\n", |
---|
| 5586 | + prog->name, relo_idx, |
---|
| 5587 | + insn_idx, (unsigned long long)imm, |
---|
| 5588 | + orig_val, new_val); |
---|
| 5589 | + return -EINVAL; |
---|
| 5590 | + } |
---|
| 5591 | + |
---|
| 5592 | + insn[0].imm = new_val; |
---|
| 5593 | + insn[1].imm = 0; /* currently only 32-bit values are supported */ |
---|
| 5594 | + pr_debug("prog '%s': relo #%d: patched insn #%d (LDIMM64) imm64 %llu -> %u\n", |
---|
| 5595 | + prog->name, relo_idx, insn_idx, |
---|
| 5596 | + (unsigned long long)imm, new_val); |
---|
| 5597 | + break; |
---|
| 5598 | + } |
---|
| 5599 | + default: |
---|
| 5600 | + pr_warn("prog '%s': relo #%d: trying to relocate unrecognized insn #%d, code:0x%x, src:0x%x, dst:0x%x, off:0x%x, imm:0x%x\n", |
---|
| 5601 | + prog->name, relo_idx, insn_idx, insn->code, |
---|
| 5602 | + insn->src_reg, insn->dst_reg, insn->off, insn->imm); |
---|
| 5603 | + return -EINVAL; |
---|
| 5604 | + } |
---|
| 5605 | + |
---|
| 5606 | + return 0; |
---|
| 5607 | +} |
---|
| 5608 | + |
---|
| 5609 | +/* Output spec definition in the format: |
---|
| 5610 | + * [<type-id>] (<type-name>) + <raw-spec> => <offset>@<spec>, |
---|
| 5611 | + * where <spec> is a C-syntax view of recorded field access, e.g.: x.a[3].b |
---|
| 5612 | + */ |
---|
| 5613 | +static void bpf_core_dump_spec(int level, const struct bpf_core_spec *spec) |
---|
| 5614 | +{ |
---|
| 5615 | + const struct btf_type *t; |
---|
| 5616 | + const struct btf_enum *e; |
---|
| 5617 | + const char *s; |
---|
| 5618 | + __u32 type_id; |
---|
| 5619 | + int i; |
---|
| 5620 | + |
---|
| 5621 | + type_id = spec->root_type_id; |
---|
| 5622 | + t = btf__type_by_id(spec->btf, type_id); |
---|
| 5623 | + s = btf__name_by_offset(spec->btf, t->name_off); |
---|
| 5624 | + |
---|
| 5625 | + libbpf_print(level, "[%u] %s %s", type_id, btf_kind_str(t), str_is_empty(s) ? "<anon>" : s); |
---|
| 5626 | + |
---|
| 5627 | + if (core_relo_is_type_based(spec->relo_kind)) |
---|
| 5628 | + return; |
---|
| 5629 | + |
---|
| 5630 | + if (core_relo_is_enumval_based(spec->relo_kind)) { |
---|
| 5631 | + t = skip_mods_and_typedefs(spec->btf, type_id, NULL); |
---|
| 5632 | + e = btf_enum(t) + spec->raw_spec[0]; |
---|
| 5633 | + s = btf__name_by_offset(spec->btf, e->name_off); |
---|
| 5634 | + |
---|
| 5635 | + libbpf_print(level, "::%s = %u", s, e->val); |
---|
| 5636 | + return; |
---|
| 5637 | + } |
---|
| 5638 | + |
---|
| 5639 | + if (core_relo_is_field_based(spec->relo_kind)) { |
---|
| 5640 | + for (i = 0; i < spec->len; i++) { |
---|
| 5641 | + if (spec->spec[i].name) |
---|
| 5642 | + libbpf_print(level, ".%s", spec->spec[i].name); |
---|
| 5643 | + else if (i > 0 || spec->spec[i].idx > 0) |
---|
| 5644 | + libbpf_print(level, "[%u]", spec->spec[i].idx); |
---|
| 5645 | + } |
---|
| 5646 | + |
---|
| 5647 | + libbpf_print(level, " ("); |
---|
| 5648 | + for (i = 0; i < spec->raw_len; i++) |
---|
| 5649 | + libbpf_print(level, "%s%d", i == 0 ? "" : ":", spec->raw_spec[i]); |
---|
| 5650 | + |
---|
| 5651 | + if (spec->bit_offset % 8) |
---|
| 5652 | + libbpf_print(level, " @ offset %u.%u)", |
---|
| 5653 | + spec->bit_offset / 8, spec->bit_offset % 8); |
---|
| 5654 | + else |
---|
| 5655 | + libbpf_print(level, " @ offset %u)", spec->bit_offset / 8); |
---|
| 5656 | + return; |
---|
| 5657 | + } |
---|
| 5658 | +} |
---|
| 5659 | + |
---|
| 5660 | +static size_t bpf_core_hash_fn(const void *key, void *ctx) |
---|
| 5661 | +{ |
---|
| 5662 | + return (size_t)key; |
---|
| 5663 | +} |
---|
| 5664 | + |
---|
| 5665 | +static bool bpf_core_equal_fn(const void *k1, const void *k2, void *ctx) |
---|
| 5666 | +{ |
---|
| 5667 | + return k1 == k2; |
---|
| 5668 | +} |
---|
| 5669 | + |
---|
| 5670 | +static void *u32_as_hash_key(__u32 x) |
---|
| 5671 | +{ |
---|
| 5672 | + return (void *)(uintptr_t)x; |
---|
| 5673 | +} |
---|
| 5674 | + |
---|
| 5675 | +/* |
---|
| 5676 | + * CO-RE relocate single instruction. |
---|
| 5677 | + * |
---|
| 5678 | + * The outline and important points of the algorithm: |
---|
| 5679 | + * 1. For given local type, find corresponding candidate target types. |
---|
| 5680 | + * Candidate type is a type with the same "essential" name, ignoring |
---|
| 5681 | + * everything after last triple underscore (___). E.g., `sample`, |
---|
| 5682 | + * `sample___flavor_one`, `sample___flavor_another_one`, are all candidates |
---|
| 5683 | + * for each other. Names with triple underscore are referred to as |
---|
| 5684 | + * "flavors" and are useful, among other things, to allow to |
---|
| 5685 | + * specify/support incompatible variations of the same kernel struct, which |
---|
| 5686 | + * might differ between different kernel versions and/or build |
---|
| 5687 | + * configurations. |
---|
| 5688 | + * |
---|
| 5689 | + * N.B. Struct "flavors" could be generated by bpftool's BTF-to-C |
---|
| 5690 | + * converter, when deduplicated BTF of a kernel still contains more than |
---|
| 5691 | + * one different types with the same name. In that case, ___2, ___3, etc |
---|
| 5692 | + * are appended starting from second name conflict. But start flavors are |
---|
| 5693 | + * also useful to be defined "locally", in BPF program, to extract same |
---|
| 5694 | + * data from incompatible changes between different kernel |
---|
| 5695 | + * versions/configurations. For instance, to handle field renames between |
---|
| 5696 | + * kernel versions, one can use two flavors of the struct name with the |
---|
| 5697 | + * same common name and use conditional relocations to extract that field, |
---|
| 5698 | + * depending on target kernel version. |
---|
| 5699 | + * 2. For each candidate type, try to match local specification to this |
---|
| 5700 | + * candidate target type. Matching involves finding corresponding |
---|
| 5701 | + * high-level spec accessors, meaning that all named fields should match, |
---|
| 5702 | + * as well as all array accesses should be within the actual bounds. Also, |
---|
| 5703 | + * types should be compatible (see bpf_core_fields_are_compat for details). |
---|
| 5704 | + * 3. It is supported and expected that there might be multiple flavors |
---|
| 5705 | + * matching the spec. As long as all the specs resolve to the same set of |
---|
| 5706 | + * offsets across all candidates, there is no error. If there is any |
---|
| 5707 | + * ambiguity, CO-RE relocation will fail. This is necessary to accomodate |
---|
| 5708 | + * imprefection of BTF deduplication, which can cause slight duplication of |
---|
| 5709 | + * the same BTF type, if some directly or indirectly referenced (by |
---|
| 5710 | + * pointer) type gets resolved to different actual types in different |
---|
| 5711 | + * object files. If such situation occurs, deduplicated BTF will end up |
---|
| 5712 | + * with two (or more) structurally identical types, which differ only in |
---|
| 5713 | + * types they refer to through pointer. This should be OK in most cases and |
---|
| 5714 | + * is not an error. |
---|
| 5715 | + * 4. Candidate types search is performed by linearly scanning through all |
---|
| 5716 | + * types in target BTF. It is anticipated that this is overall more |
---|
| 5717 | + * efficient memory-wise and not significantly worse (if not better) |
---|
| 5718 | + * CPU-wise compared to prebuilding a map from all local type names to |
---|
| 5719 | + * a list of candidate type names. It's also sped up by caching resolved |
---|
| 5720 | + * list of matching candidates per each local "root" type ID, that has at |
---|
| 5721 | + * least one bpf_core_relo associated with it. This list is shared |
---|
| 5722 | + * between multiple relocations for the same type ID and is updated as some |
---|
| 5723 | + * of the candidates are pruned due to structural incompatibility. |
---|
| 5724 | + */ |
---|
| 5725 | +static int bpf_core_apply_relo(struct bpf_program *prog, |
---|
| 5726 | + const struct bpf_core_relo *relo, |
---|
| 5727 | + int relo_idx, |
---|
| 5728 | + const struct btf *local_btf, |
---|
| 5729 | + const struct btf *targ_btf, |
---|
| 5730 | + struct hashmap *cand_cache) |
---|
| 5731 | +{ |
---|
| 5732 | + struct bpf_core_spec local_spec, cand_spec, targ_spec = {}; |
---|
| 5733 | + const void *type_key = u32_as_hash_key(relo->type_id); |
---|
| 5734 | + struct bpf_core_relo_res cand_res, targ_res; |
---|
| 5735 | + const struct btf_type *local_type; |
---|
| 5736 | + const char *local_name; |
---|
| 5737 | + struct ids_vec *cand_ids; |
---|
| 5738 | + __u32 local_id, cand_id; |
---|
| 5739 | + const char *spec_str; |
---|
| 5740 | + int i, j, err; |
---|
| 5741 | + |
---|
| 5742 | + local_id = relo->type_id; |
---|
| 5743 | + local_type = btf__type_by_id(local_btf, local_id); |
---|
| 5744 | + if (!local_type) |
---|
| 5745 | + return -EINVAL; |
---|
| 5746 | + |
---|
| 5747 | + local_name = btf__name_by_offset(local_btf, local_type->name_off); |
---|
| 5748 | + if (!local_name) |
---|
| 5749 | + return -EINVAL; |
---|
| 5750 | + |
---|
| 5751 | + spec_str = btf__name_by_offset(local_btf, relo->access_str_off); |
---|
| 5752 | + if (str_is_empty(spec_str)) |
---|
| 5753 | + return -EINVAL; |
---|
| 5754 | + |
---|
| 5755 | + err = bpf_core_parse_spec(local_btf, local_id, spec_str, relo->kind, &local_spec); |
---|
| 5756 | + if (err) { |
---|
| 5757 | + pr_warn("prog '%s': relo #%d: parsing [%d] %s %s + %s failed: %d\n", |
---|
| 5758 | + prog->name, relo_idx, local_id, btf_kind_str(local_type), |
---|
| 5759 | + str_is_empty(local_name) ? "<anon>" : local_name, |
---|
| 5760 | + spec_str, err); |
---|
| 5761 | + return -EINVAL; |
---|
| 5762 | + } |
---|
| 5763 | + |
---|
| 5764 | + pr_debug("prog '%s': relo #%d: kind <%s> (%d), spec is ", prog->name, |
---|
| 5765 | + relo_idx, core_relo_kind_str(relo->kind), relo->kind); |
---|
| 5766 | + bpf_core_dump_spec(LIBBPF_DEBUG, &local_spec); |
---|
| 5767 | + libbpf_print(LIBBPF_DEBUG, "\n"); |
---|
| 5768 | + |
---|
| 5769 | + /* TYPE_ID_LOCAL relo is special and doesn't need candidate search */ |
---|
| 5770 | + if (relo->kind == BPF_TYPE_ID_LOCAL) { |
---|
| 5771 | + targ_res.validate = true; |
---|
| 5772 | + targ_res.poison = false; |
---|
| 5773 | + targ_res.orig_val = local_spec.root_type_id; |
---|
| 5774 | + targ_res.new_val = local_spec.root_type_id; |
---|
| 5775 | + goto patch_insn; |
---|
| 5776 | + } |
---|
| 5777 | + |
---|
| 5778 | + /* libbpf doesn't support candidate search for anonymous types */ |
---|
| 5779 | + if (str_is_empty(spec_str)) { |
---|
| 5780 | + pr_warn("prog '%s': relo #%d: <%s> (%d) relocation doesn't support anonymous types\n", |
---|
| 5781 | + prog->name, relo_idx, core_relo_kind_str(relo->kind), relo->kind); |
---|
| 5782 | + return -EOPNOTSUPP; |
---|
| 5783 | + } |
---|
| 5784 | + |
---|
| 5785 | + if (!hashmap__find(cand_cache, type_key, (void **)&cand_ids)) { |
---|
| 5786 | + cand_ids = bpf_core_find_cands(local_btf, local_id, targ_btf); |
---|
| 5787 | + if (IS_ERR(cand_ids)) { |
---|
| 5788 | + pr_warn("prog '%s': relo #%d: target candidate search failed for [%d] %s %s: %ld", |
---|
| 5789 | + prog->name, relo_idx, local_id, btf_kind_str(local_type), |
---|
| 5790 | + local_name, PTR_ERR(cand_ids)); |
---|
| 5791 | + return PTR_ERR(cand_ids); |
---|
| 5792 | + } |
---|
| 5793 | + err = hashmap__set(cand_cache, type_key, cand_ids, NULL, NULL); |
---|
| 5794 | + if (err) { |
---|
| 5795 | + bpf_core_free_cands(cand_ids); |
---|
| 5796 | + return err; |
---|
| 5797 | + } |
---|
| 5798 | + } |
---|
| 5799 | + |
---|
| 5800 | + for (i = 0, j = 0; i < cand_ids->len; i++) { |
---|
| 5801 | + cand_id = cand_ids->data[i]; |
---|
| 5802 | + err = bpf_core_spec_match(&local_spec, targ_btf, cand_id, &cand_spec); |
---|
| 5803 | + if (err < 0) { |
---|
| 5804 | + pr_warn("prog '%s': relo #%d: error matching candidate #%d ", |
---|
| 5805 | + prog->name, relo_idx, i); |
---|
| 5806 | + bpf_core_dump_spec(LIBBPF_WARN, &cand_spec); |
---|
| 5807 | + libbpf_print(LIBBPF_WARN, ": %d\n", err); |
---|
| 5808 | + return err; |
---|
| 5809 | + } |
---|
| 5810 | + |
---|
| 5811 | + pr_debug("prog '%s': relo #%d: %s candidate #%d ", prog->name, |
---|
| 5812 | + relo_idx, err == 0 ? "non-matching" : "matching", i); |
---|
| 5813 | + bpf_core_dump_spec(LIBBPF_DEBUG, &cand_spec); |
---|
| 5814 | + libbpf_print(LIBBPF_DEBUG, "\n"); |
---|
| 5815 | + |
---|
| 5816 | + if (err == 0) |
---|
| 5817 | + continue; |
---|
| 5818 | + |
---|
| 5819 | + err = bpf_core_calc_relo(prog, relo, relo_idx, &local_spec, &cand_spec, &cand_res); |
---|
| 5820 | + if (err) |
---|
| 5821 | + return err; |
---|
| 5822 | + |
---|
| 5823 | + if (j == 0) { |
---|
| 5824 | + targ_res = cand_res; |
---|
| 5825 | + targ_spec = cand_spec; |
---|
| 5826 | + } else if (cand_spec.bit_offset != targ_spec.bit_offset) { |
---|
| 5827 | + /* if there are many field relo candidates, they |
---|
| 5828 | + * should all resolve to the same bit offset |
---|
| 5829 | + */ |
---|
| 5830 | + pr_warn("prog '%s': relo #%d: field offset ambiguity: %u != %u\n", |
---|
| 5831 | + prog->name, relo_idx, cand_spec.bit_offset, |
---|
| 5832 | + targ_spec.bit_offset); |
---|
| 5833 | + return -EINVAL; |
---|
| 5834 | + } else if (cand_res.poison != targ_res.poison || cand_res.new_val != targ_res.new_val) { |
---|
| 5835 | + /* all candidates should result in the same relocation |
---|
| 5836 | + * decision and value, otherwise it's dangerous to |
---|
| 5837 | + * proceed due to ambiguity |
---|
| 5838 | + */ |
---|
| 5839 | + pr_warn("prog '%s': relo #%d: relocation decision ambiguity: %s %u != %s %u\n", |
---|
| 5840 | + prog->name, relo_idx, |
---|
| 5841 | + cand_res.poison ? "failure" : "success", cand_res.new_val, |
---|
| 5842 | + targ_res.poison ? "failure" : "success", targ_res.new_val); |
---|
| 5843 | + return -EINVAL; |
---|
| 5844 | + } |
---|
| 5845 | + |
---|
| 5846 | + cand_ids->data[j++] = cand_spec.root_type_id; |
---|
| 5847 | + } |
---|
| 5848 | + |
---|
| 5849 | + /* |
---|
| 5850 | + * For BPF_FIELD_EXISTS relo or when used BPF program has field |
---|
| 5851 | + * existence checks or kernel version/config checks, it's expected |
---|
| 5852 | + * that we might not find any candidates. In this case, if field |
---|
| 5853 | + * wasn't found in any candidate, the list of candidates shouldn't |
---|
| 5854 | + * change at all, we'll just handle relocating appropriately, |
---|
| 5855 | + * depending on relo's kind. |
---|
| 5856 | + */ |
---|
| 5857 | + if (j > 0) |
---|
| 5858 | + cand_ids->len = j; |
---|
| 5859 | + |
---|
| 5860 | + /* |
---|
| 5861 | + * If no candidates were found, it might be both a programmer error, |
---|
| 5862 | + * as well as expected case, depending whether instruction w/ |
---|
| 5863 | + * relocation is guarded in some way that makes it unreachable (dead |
---|
| 5864 | + * code) if relocation can't be resolved. This is handled in |
---|
| 5865 | + * bpf_core_patch_insn() uniformly by replacing that instruction with |
---|
| 5866 | + * BPF helper call insn (using invalid helper ID). If that instruction |
---|
| 5867 | + * is indeed unreachable, then it will be ignored and eliminated by |
---|
| 5868 | + * verifier. If it was an error, then verifier will complain and point |
---|
| 5869 | + * to a specific instruction number in its log. |
---|
| 5870 | + */ |
---|
| 5871 | + if (j == 0) { |
---|
| 5872 | + pr_debug("prog '%s': relo #%d: no matching targets found\n", |
---|
| 5873 | + prog->name, relo_idx); |
---|
| 5874 | + |
---|
| 5875 | + /* calculate single target relo result explicitly */ |
---|
| 5876 | + err = bpf_core_calc_relo(prog, relo, relo_idx, &local_spec, NULL, &targ_res); |
---|
| 5877 | + if (err) |
---|
| 5878 | + return err; |
---|
| 5879 | + } |
---|
| 5880 | + |
---|
| 5881 | +patch_insn: |
---|
| 5882 | + /* bpf_core_patch_insn() should know how to handle missing targ_spec */ |
---|
| 5883 | + err = bpf_core_patch_insn(prog, relo, relo_idx, &targ_res); |
---|
| 5884 | + if (err) { |
---|
| 5885 | + pr_warn("prog '%s': relo #%d: failed to patch insn at offset %d: %d\n", |
---|
| 5886 | + prog->name, relo_idx, relo->insn_off, err); |
---|
| 5887 | + return -EINVAL; |
---|
| 5888 | + } |
---|
| 5889 | + |
---|
| 5890 | + return 0; |
---|
| 5891 | +} |
---|
| 5892 | + |
---|
| 5893 | +static int |
---|
| 5894 | +bpf_object__relocate_core(struct bpf_object *obj, const char *targ_btf_path) |
---|
| 5895 | +{ |
---|
| 5896 | + const struct btf_ext_info_sec *sec; |
---|
| 5897 | + const struct bpf_core_relo *rec; |
---|
| 5898 | + const struct btf_ext_info *seg; |
---|
| 5899 | + struct hashmap_entry *entry; |
---|
| 5900 | + struct hashmap *cand_cache = NULL; |
---|
| 5901 | + struct bpf_program *prog; |
---|
| 5902 | + struct btf *targ_btf; |
---|
| 5903 | + const char *sec_name; |
---|
| 5904 | + int i, err = 0, insn_idx, sec_idx; |
---|
| 5905 | + |
---|
| 5906 | + if (obj->btf_ext->core_relo_info.len == 0) |
---|
| 5907 | + return 0; |
---|
| 5908 | + |
---|
| 5909 | + if (targ_btf_path) |
---|
| 5910 | + targ_btf = btf__parse(targ_btf_path, NULL); |
---|
| 5911 | + else |
---|
| 5912 | + targ_btf = obj->btf_vmlinux; |
---|
| 5913 | + if (IS_ERR_OR_NULL(targ_btf)) { |
---|
| 5914 | + pr_warn("failed to get target BTF: %ld\n", PTR_ERR(targ_btf)); |
---|
| 5915 | + return PTR_ERR(targ_btf); |
---|
| 5916 | + } |
---|
| 5917 | + |
---|
| 5918 | + cand_cache = hashmap__new(bpf_core_hash_fn, bpf_core_equal_fn, NULL); |
---|
| 5919 | + if (IS_ERR(cand_cache)) { |
---|
| 5920 | + err = PTR_ERR(cand_cache); |
---|
| 5921 | + goto out; |
---|
| 5922 | + } |
---|
| 5923 | + |
---|
| 5924 | + seg = &obj->btf_ext->core_relo_info; |
---|
| 5925 | + for_each_btf_ext_sec(seg, sec) { |
---|
| 5926 | + sec_name = btf__name_by_offset(obj->btf, sec->sec_name_off); |
---|
| 5927 | + if (str_is_empty(sec_name)) { |
---|
| 5928 | + err = -EINVAL; |
---|
| 5929 | + goto out; |
---|
| 5930 | + } |
---|
| 5931 | + /* bpf_object's ELF is gone by now so it's not easy to find |
---|
| 5932 | + * section index by section name, but we can find *any* |
---|
| 5933 | + * bpf_program within desired section name and use it's |
---|
| 5934 | + * prog->sec_idx to do a proper search by section index and |
---|
| 5935 | + * instruction offset |
---|
| 5936 | + */ |
---|
| 5937 | + prog = NULL; |
---|
| 5938 | + for (i = 0; i < obj->nr_programs; i++) { |
---|
| 5939 | + if (strcmp(obj->programs[i].sec_name, sec_name) == 0) { |
---|
| 5940 | + prog = &obj->programs[i]; |
---|
| 5941 | + break; |
---|
| 5942 | + } |
---|
| 5943 | + } |
---|
| 5944 | + if (!prog) { |
---|
| 5945 | + pr_warn("sec '%s': failed to find a BPF program\n", sec_name); |
---|
| 5946 | + return -ENOENT; |
---|
| 5947 | + } |
---|
| 5948 | + sec_idx = prog->sec_idx; |
---|
| 5949 | + |
---|
| 5950 | + pr_debug("sec '%s': found %d CO-RE relocations\n", |
---|
| 5951 | + sec_name, sec->num_info); |
---|
| 5952 | + |
---|
| 5953 | + for_each_btf_ext_rec(seg, sec, i, rec) { |
---|
| 5954 | + insn_idx = rec->insn_off / BPF_INSN_SZ; |
---|
| 5955 | + prog = find_prog_by_sec_insn(obj, sec_idx, insn_idx); |
---|
| 5956 | + if (!prog) { |
---|
| 5957 | + /* When __weak subprog is "overridden" by another instance |
---|
| 5958 | + * of the subprog from a different object file, linker still |
---|
| 5959 | + * appends all the .BTF.ext info that used to belong to that |
---|
| 5960 | + * eliminated subprogram. |
---|
| 5961 | + * This is similar to what x86-64 linker does for relocations. |
---|
| 5962 | + * So just ignore such relocations just like we ignore |
---|
| 5963 | + * subprog instructions when discovering subprograms. |
---|
| 5964 | + */ |
---|
| 5965 | + pr_debug("sec '%s': skipping CO-RE relocation #%d for insn #%d belonging to eliminated weak subprogram\n", |
---|
| 5966 | + sec_name, i, insn_idx); |
---|
| 5967 | + continue; |
---|
| 5968 | + } |
---|
| 5969 | + /* no need to apply CO-RE relocation if the program is |
---|
| 5970 | + * not going to be loaded |
---|
| 5971 | + */ |
---|
| 5972 | + if (!prog->load) |
---|
| 5973 | + continue; |
---|
| 5974 | + |
---|
| 5975 | + err = bpf_core_apply_relo(prog, rec, i, obj->btf, |
---|
| 5976 | + targ_btf, cand_cache); |
---|
| 5977 | + if (err) { |
---|
| 5978 | + pr_warn("prog '%s': relo #%d: failed to relocate: %d\n", |
---|
| 5979 | + prog->name, i, err); |
---|
| 5980 | + goto out; |
---|
| 5981 | + } |
---|
| 5982 | + } |
---|
| 5983 | + } |
---|
| 5984 | + |
---|
| 5985 | +out: |
---|
| 5986 | + /* obj->btf_vmlinux is freed at the end of object load phase */ |
---|
| 5987 | + if (targ_btf != obj->btf_vmlinux) |
---|
| 5988 | + btf__free(targ_btf); |
---|
| 5989 | + if (!IS_ERR_OR_NULL(cand_cache)) { |
---|
| 5990 | + hashmap__for_each_entry(cand_cache, entry, i) { |
---|
| 5991 | + bpf_core_free_cands(entry->value); |
---|
| 5992 | + } |
---|
| 5993 | + hashmap__free(cand_cache); |
---|
| 5994 | + } |
---|
| 5995 | + return err; |
---|
| 5996 | +} |
---|
| 5997 | + |
---|
| 5998 | +/* Relocate data references within program code: |
---|
| 5999 | + * - map references; |
---|
| 6000 | + * - global variable references; |
---|
| 6001 | + * - extern references. |
---|
| 6002 | + */ |
---|
| 6003 | +static int |
---|
| 6004 | +bpf_object__relocate_data(struct bpf_object *obj, struct bpf_program *prog) |
---|
| 6005 | +{ |
---|
| 6006 | + int i; |
---|
| 6007 | + |
---|
| 6008 | + for (i = 0; i < prog->nr_reloc; i++) { |
---|
| 6009 | + struct reloc_desc *relo = &prog->reloc_desc[i]; |
---|
| 6010 | + struct bpf_insn *insn = &prog->insns[relo->insn_idx]; |
---|
| 6011 | + struct extern_desc *ext; |
---|
| 6012 | + |
---|
| 6013 | + switch (relo->type) { |
---|
| 6014 | + case RELO_LD64: |
---|
| 6015 | + insn[0].src_reg = BPF_PSEUDO_MAP_FD; |
---|
| 6016 | + insn[0].imm = obj->maps[relo->map_idx].fd; |
---|
| 6017 | + relo->processed = true; |
---|
| 6018 | + break; |
---|
| 6019 | + case RELO_DATA: |
---|
| 6020 | + insn[0].src_reg = BPF_PSEUDO_MAP_VALUE; |
---|
| 6021 | + insn[1].imm = insn[0].imm + relo->sym_off; |
---|
| 6022 | + insn[0].imm = obj->maps[relo->map_idx].fd; |
---|
| 6023 | + relo->processed = true; |
---|
| 6024 | + break; |
---|
| 6025 | + case RELO_EXTERN: |
---|
| 6026 | + ext = &obj->externs[relo->sym_off]; |
---|
| 6027 | + if (ext->type == EXT_KCFG) { |
---|
| 6028 | + insn[0].src_reg = BPF_PSEUDO_MAP_VALUE; |
---|
| 6029 | + insn[0].imm = obj->maps[obj->kconfig_map_idx].fd; |
---|
| 6030 | + insn[1].imm = ext->kcfg.data_off; |
---|
| 6031 | + } else /* EXT_KSYM */ { |
---|
| 6032 | + if (ext->ksym.type_id) { /* typed ksyms */ |
---|
| 6033 | + insn[0].src_reg = BPF_PSEUDO_BTF_ID; |
---|
| 6034 | + insn[0].imm = ext->ksym.vmlinux_btf_id; |
---|
| 6035 | + } else { /* typeless ksyms */ |
---|
| 6036 | + insn[0].imm = (__u32)ext->ksym.addr; |
---|
| 6037 | + insn[1].imm = ext->ksym.addr >> 32; |
---|
| 6038 | + } |
---|
| 6039 | + } |
---|
| 6040 | + relo->processed = true; |
---|
| 6041 | + break; |
---|
| 6042 | + case RELO_CALL: |
---|
| 6043 | + /* will be handled as a follow up pass */ |
---|
| 6044 | + break; |
---|
| 6045 | + default: |
---|
| 6046 | + pr_warn("prog '%s': relo #%d: bad relo type %d\n", |
---|
| 6047 | + prog->name, i, relo->type); |
---|
| 6048 | + return -EINVAL; |
---|
| 6049 | + } |
---|
| 6050 | + } |
---|
| 6051 | + |
---|
| 6052 | + return 0; |
---|
| 6053 | +} |
---|
| 6054 | + |
---|
| 6055 | +static int adjust_prog_btf_ext_info(const struct bpf_object *obj, |
---|
| 6056 | + const struct bpf_program *prog, |
---|
| 6057 | + const struct btf_ext_info *ext_info, |
---|
| 6058 | + void **prog_info, __u32 *prog_rec_cnt, |
---|
| 6059 | + __u32 *prog_rec_sz) |
---|
| 6060 | +{ |
---|
| 6061 | + void *copy_start = NULL, *copy_end = NULL; |
---|
| 6062 | + void *rec, *rec_end, *new_prog_info; |
---|
| 6063 | + const struct btf_ext_info_sec *sec; |
---|
| 6064 | + size_t old_sz, new_sz; |
---|
| 6065 | + const char *sec_name; |
---|
| 6066 | + int i, off_adj; |
---|
| 6067 | + |
---|
| 6068 | + for_each_btf_ext_sec(ext_info, sec) { |
---|
| 6069 | + sec_name = btf__name_by_offset(obj->btf, sec->sec_name_off); |
---|
| 6070 | + if (!sec_name) |
---|
| 6071 | + return -EINVAL; |
---|
| 6072 | + if (strcmp(sec_name, prog->sec_name) != 0) |
---|
| 6073 | + continue; |
---|
| 6074 | + |
---|
| 6075 | + for_each_btf_ext_rec(ext_info, sec, i, rec) { |
---|
| 6076 | + __u32 insn_off = *(__u32 *)rec / BPF_INSN_SZ; |
---|
| 6077 | + |
---|
| 6078 | + if (insn_off < prog->sec_insn_off) |
---|
| 6079 | + continue; |
---|
| 6080 | + if (insn_off >= prog->sec_insn_off + prog->sec_insn_cnt) |
---|
| 6081 | + break; |
---|
| 6082 | + |
---|
| 6083 | + if (!copy_start) |
---|
| 6084 | + copy_start = rec; |
---|
| 6085 | + copy_end = rec + ext_info->rec_size; |
---|
| 6086 | + } |
---|
| 6087 | + |
---|
| 6088 | + if (!copy_start) |
---|
| 6089 | + return -ENOENT; |
---|
| 6090 | + |
---|
| 6091 | + /* append func/line info of a given (sub-)program to the main |
---|
| 6092 | + * program func/line info |
---|
| 6093 | + */ |
---|
| 6094 | + old_sz = (size_t)(*prog_rec_cnt) * ext_info->rec_size; |
---|
| 6095 | + new_sz = old_sz + (copy_end - copy_start); |
---|
| 6096 | + new_prog_info = realloc(*prog_info, new_sz); |
---|
| 6097 | + if (!new_prog_info) |
---|
| 6098 | + return -ENOMEM; |
---|
| 6099 | + *prog_info = new_prog_info; |
---|
| 6100 | + *prog_rec_cnt = new_sz / ext_info->rec_size; |
---|
| 6101 | + memcpy(new_prog_info + old_sz, copy_start, copy_end - copy_start); |
---|
| 6102 | + |
---|
| 6103 | + /* Kernel instruction offsets are in units of 8-byte |
---|
| 6104 | + * instructions, while .BTF.ext instruction offsets generated |
---|
| 6105 | + * by Clang are in units of bytes. So convert Clang offsets |
---|
| 6106 | + * into kernel offsets and adjust offset according to program |
---|
| 6107 | + * relocated position. |
---|
| 6108 | + */ |
---|
| 6109 | + off_adj = prog->sub_insn_off - prog->sec_insn_off; |
---|
| 6110 | + rec = new_prog_info + old_sz; |
---|
| 6111 | + rec_end = new_prog_info + new_sz; |
---|
| 6112 | + for (; rec < rec_end; rec += ext_info->rec_size) { |
---|
| 6113 | + __u32 *insn_off = rec; |
---|
| 6114 | + |
---|
| 6115 | + *insn_off = *insn_off / BPF_INSN_SZ + off_adj; |
---|
| 6116 | + } |
---|
| 6117 | + *prog_rec_sz = ext_info->rec_size; |
---|
| 6118 | + return 0; |
---|
| 6119 | + } |
---|
| 6120 | + |
---|
| 6121 | + return -ENOENT; |
---|
| 6122 | +} |
---|
| 6123 | + |
---|
| 6124 | +static int |
---|
| 6125 | +reloc_prog_func_and_line_info(const struct bpf_object *obj, |
---|
| 6126 | + struct bpf_program *main_prog, |
---|
| 6127 | + const struct bpf_program *prog) |
---|
| 6128 | +{ |
---|
| 6129 | + int err; |
---|
| 6130 | + |
---|
| 6131 | + /* no .BTF.ext relocation if .BTF.ext is missing or kernel doesn't |
---|
| 6132 | + * supprot func/line info |
---|
| 6133 | + */ |
---|
| 6134 | + if (!obj->btf_ext || !kernel_supports(FEAT_BTF_FUNC)) |
---|
| 6135 | + return 0; |
---|
| 6136 | + |
---|
| 6137 | + /* only attempt func info relocation if main program's func_info |
---|
| 6138 | + * relocation was successful |
---|
| 6139 | + */ |
---|
| 6140 | + if (main_prog != prog && !main_prog->func_info) |
---|
| 6141 | + goto line_info; |
---|
| 6142 | + |
---|
| 6143 | + err = adjust_prog_btf_ext_info(obj, prog, &obj->btf_ext->func_info, |
---|
| 6144 | + &main_prog->func_info, |
---|
| 6145 | + &main_prog->func_info_cnt, |
---|
| 6146 | + &main_prog->func_info_rec_size); |
---|
| 6147 | + if (err) { |
---|
| 6148 | + if (err != -ENOENT) { |
---|
| 6149 | + pr_warn("prog '%s': error relocating .BTF.ext function info: %d\n", |
---|
| 6150 | + prog->name, err); |
---|
| 6151 | + return err; |
---|
| 6152 | + } |
---|
| 6153 | + if (main_prog->func_info) { |
---|
| 6154 | + /* |
---|
| 6155 | + * Some info has already been found but has problem |
---|
| 6156 | + * in the last btf_ext reloc. Must have to error out. |
---|
| 6157 | + */ |
---|
| 6158 | + pr_warn("prog '%s': missing .BTF.ext function info.\n", prog->name); |
---|
| 6159 | + return err; |
---|
| 6160 | + } |
---|
| 6161 | + /* Have problem loading the very first info. Ignore the rest. */ |
---|
| 6162 | + pr_warn("prog '%s': missing .BTF.ext function info for the main program, skipping all of .BTF.ext func info.\n", |
---|
| 6163 | + prog->name); |
---|
| 6164 | + } |
---|
| 6165 | + |
---|
| 6166 | +line_info: |
---|
| 6167 | + /* don't relocate line info if main program's relocation failed */ |
---|
| 6168 | + if (main_prog != prog && !main_prog->line_info) |
---|
| 6169 | + return 0; |
---|
| 6170 | + |
---|
| 6171 | + err = adjust_prog_btf_ext_info(obj, prog, &obj->btf_ext->line_info, |
---|
| 6172 | + &main_prog->line_info, |
---|
| 6173 | + &main_prog->line_info_cnt, |
---|
| 6174 | + &main_prog->line_info_rec_size); |
---|
| 6175 | + if (err) { |
---|
| 6176 | + if (err != -ENOENT) { |
---|
| 6177 | + pr_warn("prog '%s': error relocating .BTF.ext line info: %d\n", |
---|
| 6178 | + prog->name, err); |
---|
| 6179 | + return err; |
---|
| 6180 | + } |
---|
| 6181 | + if (main_prog->line_info) { |
---|
| 6182 | + /* |
---|
| 6183 | + * Some info has already been found but has problem |
---|
| 6184 | + * in the last btf_ext reloc. Must have to error out. |
---|
| 6185 | + */ |
---|
| 6186 | + pr_warn("prog '%s': missing .BTF.ext line info.\n", prog->name); |
---|
| 6187 | + return err; |
---|
| 6188 | + } |
---|
| 6189 | + /* Have problem loading the very first info. Ignore the rest. */ |
---|
| 6190 | + pr_warn("prog '%s': missing .BTF.ext line info for the main program, skipping all of .BTF.ext line info.\n", |
---|
| 6191 | + prog->name); |
---|
| 6192 | + } |
---|
| 6193 | + return 0; |
---|
| 6194 | +} |
---|
| 6195 | + |
---|
| 6196 | +static int cmp_relo_by_insn_idx(const void *key, const void *elem) |
---|
| 6197 | +{ |
---|
| 6198 | + size_t insn_idx = *(const size_t *)key; |
---|
| 6199 | + const struct reloc_desc *relo = elem; |
---|
| 6200 | + |
---|
| 6201 | + if (insn_idx == relo->insn_idx) |
---|
| 6202 | + return 0; |
---|
| 6203 | + return insn_idx < relo->insn_idx ? -1 : 1; |
---|
| 6204 | +} |
---|
| 6205 | + |
---|
| 6206 | +static struct reloc_desc *find_prog_insn_relo(const struct bpf_program *prog, size_t insn_idx) |
---|
| 6207 | +{ |
---|
| 6208 | + return bsearch(&insn_idx, prog->reloc_desc, prog->nr_reloc, |
---|
| 6209 | + sizeof(*prog->reloc_desc), cmp_relo_by_insn_idx); |
---|
| 6210 | +} |
---|
| 6211 | + |
---|
| 6212 | +static int |
---|
| 6213 | +bpf_object__reloc_code(struct bpf_object *obj, struct bpf_program *main_prog, |
---|
| 6214 | + struct bpf_program *prog) |
---|
| 6215 | +{ |
---|
| 6216 | + size_t sub_insn_idx, insn_idx, new_cnt; |
---|
| 6217 | + struct bpf_program *subprog; |
---|
| 6218 | + struct bpf_insn *insns, *insn; |
---|
| 6219 | + struct reloc_desc *relo; |
---|
| 6220 | + int err; |
---|
| 6221 | + |
---|
| 6222 | + err = reloc_prog_func_and_line_info(obj, main_prog, prog); |
---|
| 6223 | + if (err) |
---|
| 6224 | + return err; |
---|
| 6225 | + |
---|
| 6226 | + for (insn_idx = 0; insn_idx < prog->sec_insn_cnt; insn_idx++) { |
---|
| 6227 | + insn = &main_prog->insns[prog->sub_insn_off + insn_idx]; |
---|
| 6228 | + if (!insn_is_subprog_call(insn)) |
---|
| 6229 | + continue; |
---|
| 6230 | + |
---|
| 6231 | + relo = find_prog_insn_relo(prog, insn_idx); |
---|
| 6232 | + if (relo && relo->type != RELO_CALL) { |
---|
| 6233 | + pr_warn("prog '%s': unexpected relo for insn #%zu, type %d\n", |
---|
| 6234 | + prog->name, insn_idx, relo->type); |
---|
| 6235 | + return -LIBBPF_ERRNO__RELOC; |
---|
| 6236 | + } |
---|
| 6237 | + if (relo) { |
---|
| 6238 | + /* sub-program instruction index is a combination of |
---|
| 6239 | + * an offset of a symbol pointed to by relocation and |
---|
| 6240 | + * call instruction's imm field; for global functions, |
---|
| 6241 | + * call always has imm = -1, but for static functions |
---|
| 6242 | + * relocation is against STT_SECTION and insn->imm |
---|
| 6243 | + * points to a start of a static function |
---|
| 6244 | + */ |
---|
| 6245 | + sub_insn_idx = relo->sym_off / BPF_INSN_SZ + insn->imm + 1; |
---|
| 6246 | + } else { |
---|
| 6247 | + /* if subprogram call is to a static function within |
---|
| 6248 | + * the same ELF section, there won't be any relocation |
---|
| 6249 | + * emitted, but it also means there is no additional |
---|
| 6250 | + * offset necessary, insns->imm is relative to |
---|
| 6251 | + * instruction's original position within the section |
---|
| 6252 | + */ |
---|
| 6253 | + sub_insn_idx = prog->sec_insn_off + insn_idx + insn->imm + 1; |
---|
| 6254 | + } |
---|
| 6255 | + |
---|
| 6256 | + /* we enforce that sub-programs should be in .text section */ |
---|
| 6257 | + subprog = find_prog_by_sec_insn(obj, obj->efile.text_shndx, sub_insn_idx); |
---|
| 6258 | + if (!subprog) { |
---|
| 6259 | + pr_warn("prog '%s': no .text section found yet sub-program call exists\n", |
---|
| 6260 | + prog->name); |
---|
| 6261 | + return -LIBBPF_ERRNO__RELOC; |
---|
| 6262 | + } |
---|
| 6263 | + |
---|
| 6264 | + /* if it's the first call instruction calling into this |
---|
| 6265 | + * subprogram (meaning this subprog hasn't been processed |
---|
| 6266 | + * yet) within the context of current main program: |
---|
| 6267 | + * - append it at the end of main program's instructions blog; |
---|
| 6268 | + * - process is recursively, while current program is put on hold; |
---|
| 6269 | + * - if that subprogram calls some other not yet processes |
---|
| 6270 | + * subprogram, same thing will happen recursively until |
---|
| 6271 | + * there are no more unprocesses subprograms left to append |
---|
| 6272 | + * and relocate. |
---|
| 6273 | + */ |
---|
| 6274 | + if (subprog->sub_insn_off == 0) { |
---|
| 6275 | + subprog->sub_insn_off = main_prog->insns_cnt; |
---|
| 6276 | + |
---|
| 6277 | + new_cnt = main_prog->insns_cnt + subprog->insns_cnt; |
---|
| 6278 | + insns = libbpf_reallocarray(main_prog->insns, new_cnt, sizeof(*insns)); |
---|
| 6279 | + if (!insns) { |
---|
| 6280 | + pr_warn("prog '%s': failed to realloc prog code\n", main_prog->name); |
---|
| 6281 | + return -ENOMEM; |
---|
| 6282 | + } |
---|
| 6283 | + main_prog->insns = insns; |
---|
| 6284 | + main_prog->insns_cnt = new_cnt; |
---|
| 6285 | + |
---|
| 6286 | + memcpy(main_prog->insns + subprog->sub_insn_off, subprog->insns, |
---|
| 6287 | + subprog->insns_cnt * sizeof(*insns)); |
---|
| 6288 | + |
---|
| 6289 | + pr_debug("prog '%s': added %zu insns from sub-prog '%s'\n", |
---|
| 6290 | + main_prog->name, subprog->insns_cnt, subprog->name); |
---|
| 6291 | + |
---|
| 6292 | + err = bpf_object__reloc_code(obj, main_prog, subprog); |
---|
1248 | 6293 | if (err) |
---|
1249 | 6294 | return err; |
---|
1250 | 6295 | } |
---|
| 6296 | + |
---|
| 6297 | + /* main_prog->insns memory could have been re-allocated, so |
---|
| 6298 | + * calculate pointer again |
---|
| 6299 | + */ |
---|
| 6300 | + insn = &main_prog->insns[prog->sub_insn_off + insn_idx]; |
---|
| 6301 | + /* calculate correct instruction position within current main |
---|
| 6302 | + * prog; each main prog can have a different set of |
---|
| 6303 | + * subprograms appended (potentially in different order as |
---|
| 6304 | + * well), so position of any subprog can be different for |
---|
| 6305 | + * different main programs */ |
---|
| 6306 | + insn->imm = subprog->sub_insn_off - (prog->sub_insn_off + insn_idx) - 1; |
---|
| 6307 | + |
---|
| 6308 | + if (relo) |
---|
| 6309 | + relo->processed = true; |
---|
| 6310 | + |
---|
| 6311 | + pr_debug("prog '%s': insn #%zu relocated, imm %d points to subprog '%s' (now at %zu offset)\n", |
---|
| 6312 | + prog->name, insn_idx, insn->imm, subprog->name, subprog->sub_insn_off); |
---|
1251 | 6313 | } |
---|
1252 | 6314 | |
---|
1253 | | - zfree(&prog->reloc_desc); |
---|
1254 | | - prog->nr_reloc = 0; |
---|
1255 | 6315 | return 0; |
---|
1256 | 6316 | } |
---|
1257 | 6317 | |
---|
| 6318 | +/* |
---|
| 6319 | + * Relocate sub-program calls. |
---|
| 6320 | + * |
---|
| 6321 | + * Algorithm operates as follows. Each entry-point BPF program (referred to as |
---|
| 6322 | + * main prog) is processed separately. For each subprog (non-entry functions, |
---|
| 6323 | + * that can be called from either entry progs or other subprogs) gets their |
---|
| 6324 | + * sub_insn_off reset to zero. This serves as indicator that this subprogram |
---|
| 6325 | + * hasn't been yet appended and relocated within current main prog. Once its |
---|
| 6326 | + * relocated, sub_insn_off will point at the position within current main prog |
---|
| 6327 | + * where given subprog was appended. This will further be used to relocate all |
---|
| 6328 | + * the call instructions jumping into this subprog. |
---|
| 6329 | + * |
---|
| 6330 | + * We start with main program and process all call instructions. If the call |
---|
| 6331 | + * is into a subprog that hasn't been processed (i.e., subprog->sub_insn_off |
---|
| 6332 | + * is zero), subprog instructions are appended at the end of main program's |
---|
| 6333 | + * instruction array. Then main program is "put on hold" while we recursively |
---|
| 6334 | + * process newly appended subprogram. If that subprogram calls into another |
---|
| 6335 | + * subprogram that hasn't been appended, new subprogram is appended again to |
---|
| 6336 | + * the *main* prog's instructions (subprog's instructions are always left |
---|
| 6337 | + * untouched, as they need to be in unmodified state for subsequent main progs |
---|
| 6338 | + * and subprog instructions are always sent only as part of a main prog) and |
---|
| 6339 | + * the process continues recursively. Once all the subprogs called from a main |
---|
| 6340 | + * prog or any of its subprogs are appended (and relocated), all their |
---|
| 6341 | + * positions within finalized instructions array are known, so it's easy to |
---|
| 6342 | + * rewrite call instructions with correct relative offsets, corresponding to |
---|
| 6343 | + * desired target subprog. |
---|
| 6344 | + * |
---|
| 6345 | + * Its important to realize that some subprogs might not be called from some |
---|
| 6346 | + * main prog and any of its called/used subprogs. Those will keep their |
---|
| 6347 | + * subprog->sub_insn_off as zero at all times and won't be appended to current |
---|
| 6348 | + * main prog and won't be relocated within the context of current main prog. |
---|
| 6349 | + * They might still be used from other main progs later. |
---|
| 6350 | + * |
---|
| 6351 | + * Visually this process can be shown as below. Suppose we have two main |
---|
| 6352 | + * programs mainA and mainB and BPF object contains three subprogs: subA, |
---|
| 6353 | + * subB, and subC. mainA calls only subA, mainB calls only subC, but subA and |
---|
| 6354 | + * subC both call subB: |
---|
| 6355 | + * |
---|
| 6356 | + * +--------+ +-------+ |
---|
| 6357 | + * | v v | |
---|
| 6358 | + * +--+---+ +--+-+-+ +---+--+ |
---|
| 6359 | + * | subA | | subB | | subC | |
---|
| 6360 | + * +--+---+ +------+ +---+--+ |
---|
| 6361 | + * ^ ^ |
---|
| 6362 | + * | | |
---|
| 6363 | + * +---+-------+ +------+----+ |
---|
| 6364 | + * | mainA | | mainB | |
---|
| 6365 | + * +-----------+ +-----------+ |
---|
| 6366 | + * |
---|
| 6367 | + * We'll start relocating mainA, will find subA, append it and start |
---|
| 6368 | + * processing sub A recursively: |
---|
| 6369 | + * |
---|
| 6370 | + * +-----------+------+ |
---|
| 6371 | + * | mainA | subA | |
---|
| 6372 | + * +-----------+------+ |
---|
| 6373 | + * |
---|
| 6374 | + * At this point we notice that subB is used from subA, so we append it and |
---|
| 6375 | + * relocate (there are no further subcalls from subB): |
---|
| 6376 | + * |
---|
| 6377 | + * +-----------+------+------+ |
---|
| 6378 | + * | mainA | subA | subB | |
---|
| 6379 | + * +-----------+------+------+ |
---|
| 6380 | + * |
---|
| 6381 | + * At this point, we relocate subA calls, then go one level up and finish with |
---|
| 6382 | + * relocatin mainA calls. mainA is done. |
---|
| 6383 | + * |
---|
| 6384 | + * For mainB process is similar but results in different order. We start with |
---|
| 6385 | + * mainB and skip subA and subB, as mainB never calls them (at least |
---|
| 6386 | + * directly), but we see subC is needed, so we append and start processing it: |
---|
| 6387 | + * |
---|
| 6388 | + * +-----------+------+ |
---|
| 6389 | + * | mainB | subC | |
---|
| 6390 | + * +-----------+------+ |
---|
| 6391 | + * Now we see subC needs subB, so we go back to it, append and relocate it: |
---|
| 6392 | + * |
---|
| 6393 | + * +-----------+------+------+ |
---|
| 6394 | + * | mainB | subC | subB | |
---|
| 6395 | + * +-----------+------+------+ |
---|
| 6396 | + * |
---|
| 6397 | + * At this point we unwind recursion, relocate calls in subC, then in mainB. |
---|
| 6398 | + */ |
---|
| 6399 | +static int |
---|
| 6400 | +bpf_object__relocate_calls(struct bpf_object *obj, struct bpf_program *prog) |
---|
| 6401 | +{ |
---|
| 6402 | + struct bpf_program *subprog; |
---|
| 6403 | + int i, j, err; |
---|
| 6404 | + |
---|
| 6405 | + /* mark all subprogs as not relocated (yet) within the context of |
---|
| 6406 | + * current main program |
---|
| 6407 | + */ |
---|
| 6408 | + for (i = 0; i < obj->nr_programs; i++) { |
---|
| 6409 | + subprog = &obj->programs[i]; |
---|
| 6410 | + if (!prog_is_subprog(obj, subprog)) |
---|
| 6411 | + continue; |
---|
| 6412 | + |
---|
| 6413 | + subprog->sub_insn_off = 0; |
---|
| 6414 | + for (j = 0; j < subprog->nr_reloc; j++) |
---|
| 6415 | + if (subprog->reloc_desc[j].type == RELO_CALL) |
---|
| 6416 | + subprog->reloc_desc[j].processed = false; |
---|
| 6417 | + } |
---|
| 6418 | + |
---|
| 6419 | + err = bpf_object__reloc_code(obj, prog, prog); |
---|
| 6420 | + if (err) |
---|
| 6421 | + return err; |
---|
| 6422 | + |
---|
| 6423 | + |
---|
| 6424 | + return 0; |
---|
| 6425 | +} |
---|
1258 | 6426 | |
---|
1259 | 6427 | static int |
---|
1260 | | -bpf_object__relocate(struct bpf_object *obj) |
---|
| 6428 | +bpf_object__relocate(struct bpf_object *obj, const char *targ_btf_path) |
---|
1261 | 6429 | { |
---|
1262 | 6430 | struct bpf_program *prog; |
---|
1263 | 6431 | size_t i; |
---|
1264 | 6432 | int err; |
---|
1265 | 6433 | |
---|
1266 | | - for (i = 0; i < obj->nr_programs; i++) { |
---|
1267 | | - prog = &obj->programs[i]; |
---|
1268 | | - |
---|
1269 | | - err = bpf_program__relocate(prog, obj); |
---|
| 6434 | + if (obj->btf_ext) { |
---|
| 6435 | + err = bpf_object__relocate_core(obj, targ_btf_path); |
---|
1270 | 6436 | if (err) { |
---|
1271 | | - pr_warning("failed to relocate '%s'\n", |
---|
1272 | | - prog->section_name); |
---|
| 6437 | + pr_warn("failed to perform CO-RE relocations: %d\n", |
---|
| 6438 | + err); |
---|
1273 | 6439 | return err; |
---|
1274 | 6440 | } |
---|
| 6441 | + } |
---|
| 6442 | + /* relocate data references first for all programs and sub-programs, |
---|
| 6443 | + * as they don't change relative to code locations, so subsequent |
---|
| 6444 | + * subprogram processing won't need to re-calculate any of them |
---|
| 6445 | + */ |
---|
| 6446 | + for (i = 0; i < obj->nr_programs; i++) { |
---|
| 6447 | + prog = &obj->programs[i]; |
---|
| 6448 | + err = bpf_object__relocate_data(obj, prog); |
---|
| 6449 | + if (err) { |
---|
| 6450 | + pr_warn("prog '%s': failed to relocate data references: %d\n", |
---|
| 6451 | + prog->name, err); |
---|
| 6452 | + return err; |
---|
| 6453 | + } |
---|
| 6454 | + } |
---|
| 6455 | + /* now relocate subprogram calls and append used subprograms to main |
---|
| 6456 | + * programs; each copy of subprogram code needs to be relocated |
---|
| 6457 | + * differently for each main program, because its code location might |
---|
| 6458 | + * have changed |
---|
| 6459 | + */ |
---|
| 6460 | + for (i = 0; i < obj->nr_programs; i++) { |
---|
| 6461 | + prog = &obj->programs[i]; |
---|
| 6462 | + /* sub-program's sub-calls are relocated within the context of |
---|
| 6463 | + * its main program only |
---|
| 6464 | + */ |
---|
| 6465 | + if (prog_is_subprog(obj, prog)) |
---|
| 6466 | + continue; |
---|
| 6467 | + |
---|
| 6468 | + err = bpf_object__relocate_calls(obj, prog); |
---|
| 6469 | + if (err) { |
---|
| 6470 | + pr_warn("prog '%s': failed to relocate calls: %d\n", |
---|
| 6471 | + prog->name, err); |
---|
| 6472 | + return err; |
---|
| 6473 | + } |
---|
| 6474 | + } |
---|
| 6475 | + /* free up relocation descriptors */ |
---|
| 6476 | + for (i = 0; i < obj->nr_programs; i++) { |
---|
| 6477 | + prog = &obj->programs[i]; |
---|
| 6478 | + zfree(&prog->reloc_desc); |
---|
| 6479 | + prog->nr_reloc = 0; |
---|
1275 | 6480 | } |
---|
1276 | 6481 | return 0; |
---|
1277 | 6482 | } |
---|
1278 | 6483 | |
---|
1279 | | -static int bpf_object__collect_reloc(struct bpf_object *obj) |
---|
| 6484 | +static int bpf_object__collect_st_ops_relos(struct bpf_object *obj, |
---|
| 6485 | + GElf_Shdr *shdr, Elf_Data *data); |
---|
| 6486 | + |
---|
| 6487 | +static int bpf_object__collect_map_relos(struct bpf_object *obj, |
---|
| 6488 | + GElf_Shdr *shdr, Elf_Data *data) |
---|
1280 | 6489 | { |
---|
1281 | | - int i, err; |
---|
| 6490 | + const int bpf_ptr_sz = 8, host_ptr_sz = sizeof(void *); |
---|
| 6491 | + int i, j, nrels, new_sz; |
---|
| 6492 | + const struct btf_var_secinfo *vi = NULL; |
---|
| 6493 | + const struct btf_type *sec, *var, *def; |
---|
| 6494 | + struct bpf_map *map = NULL, *targ_map; |
---|
| 6495 | + const struct btf_member *member; |
---|
| 6496 | + const char *name, *mname; |
---|
| 6497 | + Elf_Data *symbols; |
---|
| 6498 | + unsigned int moff; |
---|
| 6499 | + GElf_Sym sym; |
---|
| 6500 | + GElf_Rel rel; |
---|
| 6501 | + void *tmp; |
---|
1282 | 6502 | |
---|
1283 | | - if (!obj_elf_valid(obj)) { |
---|
1284 | | - pr_warning("Internal error: elf object is closed\n"); |
---|
1285 | | - return -LIBBPF_ERRNO__INTERNAL; |
---|
1286 | | - } |
---|
| 6503 | + if (!obj->efile.btf_maps_sec_btf_id || !obj->btf) |
---|
| 6504 | + return -EINVAL; |
---|
| 6505 | + sec = btf__type_by_id(obj->btf, obj->efile.btf_maps_sec_btf_id); |
---|
| 6506 | + if (!sec) |
---|
| 6507 | + return -EINVAL; |
---|
1287 | 6508 | |
---|
1288 | | - for (i = 0; i < obj->efile.nr_reloc; i++) { |
---|
1289 | | - GElf_Shdr *shdr = &obj->efile.reloc[i].shdr; |
---|
1290 | | - Elf_Data *data = obj->efile.reloc[i].data; |
---|
1291 | | - int idx = shdr->sh_info; |
---|
1292 | | - struct bpf_program *prog; |
---|
1293 | | - |
---|
1294 | | - if (shdr->sh_type != SHT_REL) { |
---|
1295 | | - pr_warning("internal error at %d\n", __LINE__); |
---|
1296 | | - return -LIBBPF_ERRNO__INTERNAL; |
---|
| 6509 | + symbols = obj->efile.symbols; |
---|
| 6510 | + nrels = shdr->sh_size / shdr->sh_entsize; |
---|
| 6511 | + for (i = 0; i < nrels; i++) { |
---|
| 6512 | + if (!gelf_getrel(data, i, &rel)) { |
---|
| 6513 | + pr_warn(".maps relo #%d: failed to get ELF relo\n", i); |
---|
| 6514 | + return -LIBBPF_ERRNO__FORMAT; |
---|
1297 | 6515 | } |
---|
1298 | | - |
---|
1299 | | - prog = bpf_object__find_prog_by_idx(obj, idx); |
---|
1300 | | - if (!prog) { |
---|
1301 | | - pr_warning("relocation failed: no section(%d)\n", idx); |
---|
| 6516 | + if (!gelf_getsym(symbols, GELF_R_SYM(rel.r_info), &sym)) { |
---|
| 6517 | + pr_warn(".maps relo #%d: symbol %zx not found\n", |
---|
| 6518 | + i, (size_t)GELF_R_SYM(rel.r_info)); |
---|
| 6519 | + return -LIBBPF_ERRNO__FORMAT; |
---|
| 6520 | + } |
---|
| 6521 | + name = elf_sym_str(obj, sym.st_name) ?: "<?>"; |
---|
| 6522 | + if (sym.st_shndx != obj->efile.btf_maps_shndx) { |
---|
| 6523 | + pr_warn(".maps relo #%d: '%s' isn't a BTF-defined map\n", |
---|
| 6524 | + i, name); |
---|
1302 | 6525 | return -LIBBPF_ERRNO__RELOC; |
---|
1303 | 6526 | } |
---|
1304 | 6527 | |
---|
1305 | | - err = bpf_program__collect_reloc(prog, |
---|
1306 | | - shdr, data, |
---|
1307 | | - obj); |
---|
| 6528 | + pr_debug(".maps relo #%d: for %zd value %zd rel.r_offset %zu name %d ('%s')\n", |
---|
| 6529 | + i, (ssize_t)(rel.r_info >> 32), (size_t)sym.st_value, |
---|
| 6530 | + (size_t)rel.r_offset, sym.st_name, name); |
---|
| 6531 | + |
---|
| 6532 | + for (j = 0; j < obj->nr_maps; j++) { |
---|
| 6533 | + map = &obj->maps[j]; |
---|
| 6534 | + if (map->sec_idx != obj->efile.btf_maps_shndx) |
---|
| 6535 | + continue; |
---|
| 6536 | + |
---|
| 6537 | + vi = btf_var_secinfos(sec) + map->btf_var_idx; |
---|
| 6538 | + if (vi->offset <= rel.r_offset && |
---|
| 6539 | + rel.r_offset + bpf_ptr_sz <= vi->offset + vi->size) |
---|
| 6540 | + break; |
---|
| 6541 | + } |
---|
| 6542 | + if (j == obj->nr_maps) { |
---|
| 6543 | + pr_warn(".maps relo #%d: cannot find map '%s' at rel.r_offset %zu\n", |
---|
| 6544 | + i, name, (size_t)rel.r_offset); |
---|
| 6545 | + return -EINVAL; |
---|
| 6546 | + } |
---|
| 6547 | + |
---|
| 6548 | + if (!bpf_map_type__is_map_in_map(map->def.type)) |
---|
| 6549 | + return -EINVAL; |
---|
| 6550 | + if (map->def.type == BPF_MAP_TYPE_HASH_OF_MAPS && |
---|
| 6551 | + map->def.key_size != sizeof(int)) { |
---|
| 6552 | + pr_warn(".maps relo #%d: hash-of-maps '%s' should have key size %zu.\n", |
---|
| 6553 | + i, map->name, sizeof(int)); |
---|
| 6554 | + return -EINVAL; |
---|
| 6555 | + } |
---|
| 6556 | + |
---|
| 6557 | + targ_map = bpf_object__find_map_by_name(obj, name); |
---|
| 6558 | + if (!targ_map) |
---|
| 6559 | + return -ESRCH; |
---|
| 6560 | + |
---|
| 6561 | + var = btf__type_by_id(obj->btf, vi->type); |
---|
| 6562 | + def = skip_mods_and_typedefs(obj->btf, var->type, NULL); |
---|
| 6563 | + if (btf_vlen(def) == 0) |
---|
| 6564 | + return -EINVAL; |
---|
| 6565 | + member = btf_members(def) + btf_vlen(def) - 1; |
---|
| 6566 | + mname = btf__name_by_offset(obj->btf, member->name_off); |
---|
| 6567 | + if (strcmp(mname, "values")) |
---|
| 6568 | + return -EINVAL; |
---|
| 6569 | + |
---|
| 6570 | + moff = btf_member_bit_offset(def, btf_vlen(def) - 1) / 8; |
---|
| 6571 | + if (rel.r_offset - vi->offset < moff) |
---|
| 6572 | + return -EINVAL; |
---|
| 6573 | + |
---|
| 6574 | + moff = rel.r_offset - vi->offset - moff; |
---|
| 6575 | + /* here we use BPF pointer size, which is always 64 bit, as we |
---|
| 6576 | + * are parsing ELF that was built for BPF target |
---|
| 6577 | + */ |
---|
| 6578 | + if (moff % bpf_ptr_sz) |
---|
| 6579 | + return -EINVAL; |
---|
| 6580 | + moff /= bpf_ptr_sz; |
---|
| 6581 | + if (moff >= map->init_slots_sz) { |
---|
| 6582 | + new_sz = moff + 1; |
---|
| 6583 | + tmp = libbpf_reallocarray(map->init_slots, new_sz, host_ptr_sz); |
---|
| 6584 | + if (!tmp) |
---|
| 6585 | + return -ENOMEM; |
---|
| 6586 | + map->init_slots = tmp; |
---|
| 6587 | + memset(map->init_slots + map->init_slots_sz, 0, |
---|
| 6588 | + (new_sz - map->init_slots_sz) * host_ptr_sz); |
---|
| 6589 | + map->init_slots_sz = new_sz; |
---|
| 6590 | + } |
---|
| 6591 | + map->init_slots[moff] = targ_map; |
---|
| 6592 | + |
---|
| 6593 | + pr_debug(".maps relo #%d: map '%s' slot [%d] points to map '%s'\n", |
---|
| 6594 | + i, map->name, moff, name); |
---|
| 6595 | + } |
---|
| 6596 | + |
---|
| 6597 | + return 0; |
---|
| 6598 | +} |
---|
| 6599 | + |
---|
| 6600 | +static int cmp_relocs(const void *_a, const void *_b) |
---|
| 6601 | +{ |
---|
| 6602 | + const struct reloc_desc *a = _a; |
---|
| 6603 | + const struct reloc_desc *b = _b; |
---|
| 6604 | + |
---|
| 6605 | + if (a->insn_idx != b->insn_idx) |
---|
| 6606 | + return a->insn_idx < b->insn_idx ? -1 : 1; |
---|
| 6607 | + |
---|
| 6608 | + /* no two relocations should have the same insn_idx, but ... */ |
---|
| 6609 | + if (a->type != b->type) |
---|
| 6610 | + return a->type < b->type ? -1 : 1; |
---|
| 6611 | + |
---|
| 6612 | + return 0; |
---|
| 6613 | +} |
---|
| 6614 | + |
---|
| 6615 | +static int bpf_object__collect_relos(struct bpf_object *obj) |
---|
| 6616 | +{ |
---|
| 6617 | + int i, err; |
---|
| 6618 | + |
---|
| 6619 | + for (i = 0; i < obj->efile.nr_reloc_sects; i++) { |
---|
| 6620 | + GElf_Shdr *shdr = &obj->efile.reloc_sects[i].shdr; |
---|
| 6621 | + Elf_Data *data = obj->efile.reloc_sects[i].data; |
---|
| 6622 | + int idx = shdr->sh_info; |
---|
| 6623 | + |
---|
| 6624 | + if (shdr->sh_type != SHT_REL) { |
---|
| 6625 | + pr_warn("internal error at %d\n", __LINE__); |
---|
| 6626 | + return -LIBBPF_ERRNO__INTERNAL; |
---|
| 6627 | + } |
---|
| 6628 | + |
---|
| 6629 | + if (idx == obj->efile.st_ops_shndx) |
---|
| 6630 | + err = bpf_object__collect_st_ops_relos(obj, shdr, data); |
---|
| 6631 | + else if (idx == obj->efile.btf_maps_shndx) |
---|
| 6632 | + err = bpf_object__collect_map_relos(obj, shdr, data); |
---|
| 6633 | + else |
---|
| 6634 | + err = bpf_object__collect_prog_relos(obj, shdr, data); |
---|
1308 | 6635 | if (err) |
---|
1309 | 6636 | return err; |
---|
| 6637 | + } |
---|
| 6638 | + |
---|
| 6639 | + for (i = 0; i < obj->nr_programs; i++) { |
---|
| 6640 | + struct bpf_program *p = &obj->programs[i]; |
---|
| 6641 | + |
---|
| 6642 | + if (!p->nr_reloc) |
---|
| 6643 | + continue; |
---|
| 6644 | + |
---|
| 6645 | + qsort(p->reloc_desc, p->nr_reloc, sizeof(*p->reloc_desc), cmp_relocs); |
---|
| 6646 | + } |
---|
| 6647 | + return 0; |
---|
| 6648 | +} |
---|
| 6649 | + |
---|
| 6650 | +static bool insn_is_helper_call(struct bpf_insn *insn, enum bpf_func_id *func_id) |
---|
| 6651 | +{ |
---|
| 6652 | + if (BPF_CLASS(insn->code) == BPF_JMP && |
---|
| 6653 | + BPF_OP(insn->code) == BPF_CALL && |
---|
| 6654 | + BPF_SRC(insn->code) == BPF_K && |
---|
| 6655 | + insn->src_reg == 0 && |
---|
| 6656 | + insn->dst_reg == 0) { |
---|
| 6657 | + *func_id = insn->imm; |
---|
| 6658 | + return true; |
---|
| 6659 | + } |
---|
| 6660 | + return false; |
---|
| 6661 | +} |
---|
| 6662 | + |
---|
| 6663 | +static int bpf_object__sanitize_prog(struct bpf_object* obj, struct bpf_program *prog) |
---|
| 6664 | +{ |
---|
| 6665 | + struct bpf_insn *insn = prog->insns; |
---|
| 6666 | + enum bpf_func_id func_id; |
---|
| 6667 | + int i; |
---|
| 6668 | + |
---|
| 6669 | + for (i = 0; i < prog->insns_cnt; i++, insn++) { |
---|
| 6670 | + if (!insn_is_helper_call(insn, &func_id)) |
---|
| 6671 | + continue; |
---|
| 6672 | + |
---|
| 6673 | + /* on kernels that don't yet support |
---|
| 6674 | + * bpf_probe_read_{kernel,user}[_str] helpers, fall back |
---|
| 6675 | + * to bpf_probe_read() which works well for old kernels |
---|
| 6676 | + */ |
---|
| 6677 | + switch (func_id) { |
---|
| 6678 | + case BPF_FUNC_probe_read_kernel: |
---|
| 6679 | + case BPF_FUNC_probe_read_user: |
---|
| 6680 | + if (!kernel_supports(FEAT_PROBE_READ_KERN)) |
---|
| 6681 | + insn->imm = BPF_FUNC_probe_read; |
---|
| 6682 | + break; |
---|
| 6683 | + case BPF_FUNC_probe_read_kernel_str: |
---|
| 6684 | + case BPF_FUNC_probe_read_user_str: |
---|
| 6685 | + if (!kernel_supports(FEAT_PROBE_READ_KERN)) |
---|
| 6686 | + insn->imm = BPF_FUNC_probe_read_str; |
---|
| 6687 | + break; |
---|
| 6688 | + default: |
---|
| 6689 | + break; |
---|
| 6690 | + } |
---|
1310 | 6691 | } |
---|
1311 | 6692 | return 0; |
---|
1312 | 6693 | } |
---|
1313 | 6694 | |
---|
1314 | 6695 | static int |
---|
1315 | | -load_program(enum bpf_prog_type type, enum bpf_attach_type expected_attach_type, |
---|
1316 | | - const char *name, struct bpf_insn *insns, int insns_cnt, |
---|
1317 | | - char *license, u32 kern_version, int *pfd, int prog_ifindex) |
---|
| 6696 | +load_program(struct bpf_program *prog, struct bpf_insn *insns, int insns_cnt, |
---|
| 6697 | + char *license, __u32 kern_version, int *pfd) |
---|
1318 | 6698 | { |
---|
1319 | 6699 | struct bpf_load_program_attr load_attr; |
---|
1320 | 6700 | char *cp, errmsg[STRERR_BUFSIZE]; |
---|
1321 | | - char *log_buf; |
---|
1322 | | - int ret; |
---|
| 6701 | + size_t log_buf_size = 0; |
---|
| 6702 | + char *log_buf = NULL; |
---|
| 6703 | + int btf_fd, ret; |
---|
| 6704 | + |
---|
| 6705 | + if (!insns || !insns_cnt) |
---|
| 6706 | + return -EINVAL; |
---|
1323 | 6707 | |
---|
1324 | 6708 | memset(&load_attr, 0, sizeof(struct bpf_load_program_attr)); |
---|
1325 | | - load_attr.prog_type = type; |
---|
1326 | | - load_attr.expected_attach_type = expected_attach_type; |
---|
1327 | | - load_attr.name = name; |
---|
| 6709 | + load_attr.prog_type = prog->type; |
---|
| 6710 | + /* old kernels might not support specifying expected_attach_type */ |
---|
| 6711 | + if (!kernel_supports(FEAT_EXP_ATTACH_TYPE) && prog->sec_def && |
---|
| 6712 | + prog->sec_def->is_exp_attach_type_optional) |
---|
| 6713 | + load_attr.expected_attach_type = 0; |
---|
| 6714 | + else |
---|
| 6715 | + load_attr.expected_attach_type = prog->expected_attach_type; |
---|
| 6716 | + if (kernel_supports(FEAT_PROG_NAME)) |
---|
| 6717 | + load_attr.name = prog->name; |
---|
1328 | 6718 | load_attr.insns = insns; |
---|
1329 | 6719 | load_attr.insns_cnt = insns_cnt; |
---|
1330 | 6720 | load_attr.license = license; |
---|
1331 | | - load_attr.kern_version = kern_version; |
---|
1332 | | - load_attr.prog_ifindex = prog_ifindex; |
---|
| 6721 | + if (prog->type == BPF_PROG_TYPE_STRUCT_OPS || |
---|
| 6722 | + prog->type == BPF_PROG_TYPE_LSM) { |
---|
| 6723 | + load_attr.attach_btf_id = prog->attach_btf_id; |
---|
| 6724 | + } else if (prog->type == BPF_PROG_TYPE_TRACING || |
---|
| 6725 | + prog->type == BPF_PROG_TYPE_EXT) { |
---|
| 6726 | + load_attr.attach_prog_fd = prog->attach_prog_fd; |
---|
| 6727 | + load_attr.attach_btf_id = prog->attach_btf_id; |
---|
| 6728 | + } else { |
---|
| 6729 | + load_attr.kern_version = kern_version; |
---|
| 6730 | + load_attr.prog_ifindex = prog->prog_ifindex; |
---|
| 6731 | + } |
---|
| 6732 | + /* specify func_info/line_info only if kernel supports them */ |
---|
| 6733 | + btf_fd = bpf_object__btf_fd(prog->obj); |
---|
| 6734 | + if (btf_fd >= 0 && kernel_supports(FEAT_BTF_FUNC)) { |
---|
| 6735 | + load_attr.prog_btf_fd = btf_fd; |
---|
| 6736 | + load_attr.func_info = prog->func_info; |
---|
| 6737 | + load_attr.func_info_rec_size = prog->func_info_rec_size; |
---|
| 6738 | + load_attr.func_info_cnt = prog->func_info_cnt; |
---|
| 6739 | + load_attr.line_info = prog->line_info; |
---|
| 6740 | + load_attr.line_info_rec_size = prog->line_info_rec_size; |
---|
| 6741 | + load_attr.line_info_cnt = prog->line_info_cnt; |
---|
| 6742 | + } |
---|
| 6743 | + load_attr.log_level = prog->log_level; |
---|
| 6744 | + load_attr.prog_flags = prog->prog_flags; |
---|
1333 | 6745 | |
---|
1334 | | - if (!load_attr.insns || !load_attr.insns_cnt) |
---|
1335 | | - return -EINVAL; |
---|
| 6746 | +retry_load: |
---|
| 6747 | + if (log_buf_size) { |
---|
| 6748 | + log_buf = malloc(log_buf_size); |
---|
| 6749 | + if (!log_buf) |
---|
| 6750 | + return -ENOMEM; |
---|
1336 | 6751 | |
---|
1337 | | - log_buf = malloc(BPF_LOG_BUF_SIZE); |
---|
1338 | | - if (!log_buf) |
---|
1339 | | - pr_warning("Alloc log buffer for bpf loader error, continue without log\n"); |
---|
| 6752 | + *log_buf = 0; |
---|
| 6753 | + } |
---|
1340 | 6754 | |
---|
1341 | | - ret = bpf_load_program_xattr(&load_attr, log_buf, BPF_LOG_BUF_SIZE); |
---|
| 6755 | + ret = bpf_load_program_xattr(&load_attr, log_buf, log_buf_size); |
---|
1342 | 6756 | |
---|
1343 | 6757 | if (ret >= 0) { |
---|
| 6758 | + if (log_buf && load_attr.log_level) |
---|
| 6759 | + pr_debug("verifier log:\n%s", log_buf); |
---|
| 6760 | + |
---|
| 6761 | + if (prog->obj->rodata_map_idx >= 0 && |
---|
| 6762 | + kernel_supports(FEAT_PROG_BIND_MAP)) { |
---|
| 6763 | + struct bpf_map *rodata_map = |
---|
| 6764 | + &prog->obj->maps[prog->obj->rodata_map_idx]; |
---|
| 6765 | + |
---|
| 6766 | + if (bpf_prog_bind_map(ret, bpf_map__fd(rodata_map), NULL)) { |
---|
| 6767 | + cp = libbpf_strerror_r(errno, errmsg, sizeof(errmsg)); |
---|
| 6768 | + pr_warn("prog '%s': failed to bind .rodata map: %s\n", |
---|
| 6769 | + prog->name, cp); |
---|
| 6770 | + /* Don't fail hard if can't bind rodata. */ |
---|
| 6771 | + } |
---|
| 6772 | + } |
---|
| 6773 | + |
---|
1344 | 6774 | *pfd = ret; |
---|
1345 | 6775 | ret = 0; |
---|
1346 | 6776 | goto out; |
---|
1347 | 6777 | } |
---|
1348 | 6778 | |
---|
1349 | | - ret = -LIBBPF_ERRNO__LOAD; |
---|
1350 | | - cp = str_error(errno, errmsg, sizeof(errmsg)); |
---|
1351 | | - pr_warning("load bpf program failed: %s\n", cp); |
---|
| 6779 | + if (!log_buf || errno == ENOSPC) { |
---|
| 6780 | + log_buf_size = max((size_t)BPF_LOG_BUF_SIZE, |
---|
| 6781 | + log_buf_size << 1); |
---|
| 6782 | + |
---|
| 6783 | + free(log_buf); |
---|
| 6784 | + goto retry_load; |
---|
| 6785 | + } |
---|
| 6786 | + ret = errno ? -errno : -LIBBPF_ERRNO__LOAD; |
---|
| 6787 | + cp = libbpf_strerror_r(errno, errmsg, sizeof(errmsg)); |
---|
| 6788 | + pr_warn("load bpf program failed: %s\n", cp); |
---|
| 6789 | + pr_perm_msg(ret); |
---|
1352 | 6790 | |
---|
1353 | 6791 | if (log_buf && log_buf[0] != '\0') { |
---|
1354 | 6792 | ret = -LIBBPF_ERRNO__VERIFY; |
---|
1355 | | - pr_warning("-- BEGIN DUMP LOG ---\n"); |
---|
1356 | | - pr_warning("\n%s\n", log_buf); |
---|
1357 | | - pr_warning("-- END LOG --\n"); |
---|
| 6793 | + pr_warn("-- BEGIN DUMP LOG ---\n"); |
---|
| 6794 | + pr_warn("\n%s\n", log_buf); |
---|
| 6795 | + pr_warn("-- END LOG --\n"); |
---|
1358 | 6796 | } else if (load_attr.insns_cnt >= BPF_MAXINSNS) { |
---|
1359 | | - pr_warning("Program too large (%zu insns), at most %d insns\n", |
---|
1360 | | - load_attr.insns_cnt, BPF_MAXINSNS); |
---|
| 6797 | + pr_warn("Program too large (%zu insns), at most %d insns\n", |
---|
| 6798 | + load_attr.insns_cnt, BPF_MAXINSNS); |
---|
1361 | 6799 | ret = -LIBBPF_ERRNO__PROG2BIG; |
---|
1362 | | - } else { |
---|
| 6800 | + } else if (load_attr.prog_type != BPF_PROG_TYPE_KPROBE) { |
---|
1363 | 6801 | /* Wrong program type? */ |
---|
1364 | | - if (load_attr.prog_type != BPF_PROG_TYPE_KPROBE) { |
---|
1365 | | - int fd; |
---|
| 6802 | + int fd; |
---|
1366 | 6803 | |
---|
1367 | | - load_attr.prog_type = BPF_PROG_TYPE_KPROBE; |
---|
1368 | | - load_attr.expected_attach_type = 0; |
---|
1369 | | - fd = bpf_load_program_xattr(&load_attr, NULL, 0); |
---|
1370 | | - if (fd >= 0) { |
---|
1371 | | - close(fd); |
---|
1372 | | - ret = -LIBBPF_ERRNO__PROGTYPE; |
---|
1373 | | - goto out; |
---|
1374 | | - } |
---|
| 6804 | + load_attr.prog_type = BPF_PROG_TYPE_KPROBE; |
---|
| 6805 | + load_attr.expected_attach_type = 0; |
---|
| 6806 | + fd = bpf_load_program_xattr(&load_attr, NULL, 0); |
---|
| 6807 | + if (fd >= 0) { |
---|
| 6808 | + close(fd); |
---|
| 6809 | + ret = -LIBBPF_ERRNO__PROGTYPE; |
---|
| 6810 | + goto out; |
---|
1375 | 6811 | } |
---|
1376 | | - |
---|
1377 | | - if (log_buf) |
---|
1378 | | - ret = -LIBBPF_ERRNO__KVER; |
---|
1379 | 6812 | } |
---|
1380 | 6813 | |
---|
1381 | 6814 | out: |
---|
.. | .. |
---|
1383 | 6816 | return ret; |
---|
1384 | 6817 | } |
---|
1385 | 6818 | |
---|
1386 | | -static int |
---|
1387 | | -bpf_program__load(struct bpf_program *prog, |
---|
1388 | | - char *license, u32 kern_version) |
---|
| 6819 | +static int libbpf_find_attach_btf_id(struct bpf_program *prog); |
---|
| 6820 | + |
---|
| 6821 | +int bpf_program__load(struct bpf_program *prog, char *license, __u32 kern_ver) |
---|
1389 | 6822 | { |
---|
1390 | | - int err = 0, fd, i; |
---|
| 6823 | + int err = 0, fd, i, btf_id; |
---|
| 6824 | + |
---|
| 6825 | + if (prog->obj->loaded) { |
---|
| 6826 | + pr_warn("prog '%s': can't load after object was loaded\n", prog->name); |
---|
| 6827 | + return -EINVAL; |
---|
| 6828 | + } |
---|
| 6829 | + |
---|
| 6830 | + if ((prog->type == BPF_PROG_TYPE_TRACING || |
---|
| 6831 | + prog->type == BPF_PROG_TYPE_LSM || |
---|
| 6832 | + prog->type == BPF_PROG_TYPE_EXT) && !prog->attach_btf_id) { |
---|
| 6833 | + btf_id = libbpf_find_attach_btf_id(prog); |
---|
| 6834 | + if (btf_id <= 0) |
---|
| 6835 | + return btf_id; |
---|
| 6836 | + prog->attach_btf_id = btf_id; |
---|
| 6837 | + } |
---|
1391 | 6838 | |
---|
1392 | 6839 | if (prog->instances.nr < 0 || !prog->instances.fds) { |
---|
1393 | 6840 | if (prog->preprocessor) { |
---|
1394 | | - pr_warning("Internal error: can't load program '%s'\n", |
---|
1395 | | - prog->section_name); |
---|
| 6841 | + pr_warn("Internal error: can't load program '%s'\n", |
---|
| 6842 | + prog->name); |
---|
1396 | 6843 | return -LIBBPF_ERRNO__INTERNAL; |
---|
1397 | 6844 | } |
---|
1398 | 6845 | |
---|
1399 | 6846 | prog->instances.fds = malloc(sizeof(int)); |
---|
1400 | 6847 | if (!prog->instances.fds) { |
---|
1401 | | - pr_warning("Not enough memory for BPF fds\n"); |
---|
| 6848 | + pr_warn("Not enough memory for BPF fds\n"); |
---|
1402 | 6849 | return -ENOMEM; |
---|
1403 | 6850 | } |
---|
1404 | 6851 | prog->instances.nr = 1; |
---|
.. | .. |
---|
1407 | 6854 | |
---|
1408 | 6855 | if (!prog->preprocessor) { |
---|
1409 | 6856 | if (prog->instances.nr != 1) { |
---|
1410 | | - pr_warning("Program '%s' is inconsistent: nr(%d) != 1\n", |
---|
1411 | | - prog->section_name, prog->instances.nr); |
---|
| 6857 | + pr_warn("prog '%s': inconsistent nr(%d) != 1\n", |
---|
| 6858 | + prog->name, prog->instances.nr); |
---|
1412 | 6859 | } |
---|
1413 | | - err = load_program(prog->type, prog->expected_attach_type, |
---|
1414 | | - prog->name, prog->insns, prog->insns_cnt, |
---|
1415 | | - license, kern_version, &fd, |
---|
1416 | | - prog->prog_ifindex); |
---|
| 6860 | + err = load_program(prog, prog->insns, prog->insns_cnt, |
---|
| 6861 | + license, kern_ver, &fd); |
---|
1417 | 6862 | if (!err) |
---|
1418 | 6863 | prog->instances.fds[0] = fd; |
---|
1419 | 6864 | goto out; |
---|
.. | .. |
---|
1423 | 6868 | struct bpf_prog_prep_result result; |
---|
1424 | 6869 | bpf_program_prep_t preprocessor = prog->preprocessor; |
---|
1425 | 6870 | |
---|
1426 | | - bzero(&result, sizeof(result)); |
---|
| 6871 | + memset(&result, 0, sizeof(result)); |
---|
1427 | 6872 | err = preprocessor(prog, i, prog->insns, |
---|
1428 | 6873 | prog->insns_cnt, &result); |
---|
1429 | 6874 | if (err) { |
---|
1430 | | - pr_warning("Preprocessing the %dth instance of program '%s' failed\n", |
---|
1431 | | - i, prog->section_name); |
---|
| 6875 | + pr_warn("Preprocessing the %dth instance of program '%s' failed\n", |
---|
| 6876 | + i, prog->name); |
---|
1432 | 6877 | goto out; |
---|
1433 | 6878 | } |
---|
1434 | 6879 | |
---|
1435 | 6880 | if (!result.new_insn_ptr || !result.new_insn_cnt) { |
---|
1436 | 6881 | pr_debug("Skip loading the %dth instance of program '%s'\n", |
---|
1437 | | - i, prog->section_name); |
---|
| 6882 | + i, prog->name); |
---|
1438 | 6883 | prog->instances.fds[i] = -1; |
---|
1439 | 6884 | if (result.pfd) |
---|
1440 | 6885 | *result.pfd = -1; |
---|
1441 | 6886 | continue; |
---|
1442 | 6887 | } |
---|
1443 | 6888 | |
---|
1444 | | - err = load_program(prog->type, prog->expected_attach_type, |
---|
1445 | | - prog->name, result.new_insn_ptr, |
---|
1446 | | - result.new_insn_cnt, |
---|
1447 | | - license, kern_version, &fd, |
---|
1448 | | - prog->prog_ifindex); |
---|
1449 | | - |
---|
| 6889 | + err = load_program(prog, result.new_insn_ptr, |
---|
| 6890 | + result.new_insn_cnt, license, kern_ver, &fd); |
---|
1450 | 6891 | if (err) { |
---|
1451 | | - pr_warning("Loading the %dth instance of program '%s' failed\n", |
---|
1452 | | - i, prog->section_name); |
---|
| 6892 | + pr_warn("Loading the %dth instance of program '%s' failed\n", |
---|
| 6893 | + i, prog->name); |
---|
1453 | 6894 | goto out; |
---|
1454 | 6895 | } |
---|
1455 | 6896 | |
---|
.. | .. |
---|
1459 | 6900 | } |
---|
1460 | 6901 | out: |
---|
1461 | 6902 | if (err) |
---|
1462 | | - pr_warning("failed to load program '%s'\n", |
---|
1463 | | - prog->section_name); |
---|
| 6903 | + pr_warn("failed to load program '%s'\n", prog->name); |
---|
1464 | 6904 | zfree(&prog->insns); |
---|
1465 | 6905 | prog->insns_cnt = 0; |
---|
1466 | 6906 | return err; |
---|
1467 | 6907 | } |
---|
1468 | 6908 | |
---|
1469 | | -static bool bpf_program__is_function_storage(struct bpf_program *prog, |
---|
1470 | | - struct bpf_object *obj) |
---|
1471 | | -{ |
---|
1472 | | - return prog->idx == obj->efile.text_shndx && obj->has_pseudo_calls; |
---|
1473 | | -} |
---|
1474 | | - |
---|
1475 | 6909 | static int |
---|
1476 | | -bpf_object__load_progs(struct bpf_object *obj) |
---|
| 6910 | +bpf_object__load_progs(struct bpf_object *obj, int log_level) |
---|
1477 | 6911 | { |
---|
| 6912 | + struct bpf_program *prog; |
---|
1478 | 6913 | size_t i; |
---|
1479 | 6914 | int err; |
---|
1480 | 6915 | |
---|
1481 | 6916 | for (i = 0; i < obj->nr_programs; i++) { |
---|
1482 | | - if (bpf_program__is_function_storage(&obj->programs[i], obj)) |
---|
| 6917 | + prog = &obj->programs[i]; |
---|
| 6918 | + err = bpf_object__sanitize_prog(obj, prog); |
---|
| 6919 | + if (err) |
---|
| 6920 | + return err; |
---|
| 6921 | + } |
---|
| 6922 | + |
---|
| 6923 | + for (i = 0; i < obj->nr_programs; i++) { |
---|
| 6924 | + prog = &obj->programs[i]; |
---|
| 6925 | + if (prog_is_subprog(obj, prog)) |
---|
1483 | 6926 | continue; |
---|
1484 | | - err = bpf_program__load(&obj->programs[i], |
---|
1485 | | - obj->license, |
---|
1486 | | - obj->kern_version); |
---|
| 6927 | + if (!prog->load) { |
---|
| 6928 | + pr_debug("prog '%s': skipped loading\n", prog->name); |
---|
| 6929 | + continue; |
---|
| 6930 | + } |
---|
| 6931 | + prog->log_level |= log_level; |
---|
| 6932 | + err = bpf_program__load(prog, obj->license, obj->kern_version); |
---|
1487 | 6933 | if (err) |
---|
1488 | 6934 | return err; |
---|
1489 | 6935 | } |
---|
1490 | 6936 | return 0; |
---|
1491 | 6937 | } |
---|
1492 | 6938 | |
---|
1493 | | -static bool bpf_prog_type__needs_kver(enum bpf_prog_type type) |
---|
1494 | | -{ |
---|
1495 | | - switch (type) { |
---|
1496 | | - case BPF_PROG_TYPE_SOCKET_FILTER: |
---|
1497 | | - case BPF_PROG_TYPE_SCHED_CLS: |
---|
1498 | | - case BPF_PROG_TYPE_SCHED_ACT: |
---|
1499 | | - case BPF_PROG_TYPE_XDP: |
---|
1500 | | - case BPF_PROG_TYPE_CGROUP_SKB: |
---|
1501 | | - case BPF_PROG_TYPE_CGROUP_SOCK: |
---|
1502 | | - case BPF_PROG_TYPE_LWT_IN: |
---|
1503 | | - case BPF_PROG_TYPE_LWT_OUT: |
---|
1504 | | - case BPF_PROG_TYPE_LWT_XMIT: |
---|
1505 | | - case BPF_PROG_TYPE_LWT_SEG6LOCAL: |
---|
1506 | | - case BPF_PROG_TYPE_SOCK_OPS: |
---|
1507 | | - case BPF_PROG_TYPE_SK_SKB: |
---|
1508 | | - case BPF_PROG_TYPE_CGROUP_DEVICE: |
---|
1509 | | - case BPF_PROG_TYPE_SK_MSG: |
---|
1510 | | - case BPF_PROG_TYPE_CGROUP_SOCK_ADDR: |
---|
1511 | | - case BPF_PROG_TYPE_LIRC_MODE2: |
---|
1512 | | - case BPF_PROG_TYPE_SK_REUSEPORT: |
---|
1513 | | - return false; |
---|
1514 | | - case BPF_PROG_TYPE_UNSPEC: |
---|
1515 | | - case BPF_PROG_TYPE_KPROBE: |
---|
1516 | | - case BPF_PROG_TYPE_TRACEPOINT: |
---|
1517 | | - case BPF_PROG_TYPE_PERF_EVENT: |
---|
1518 | | - case BPF_PROG_TYPE_RAW_TRACEPOINT: |
---|
1519 | | - default: |
---|
1520 | | - return true; |
---|
1521 | | - } |
---|
1522 | | -} |
---|
1523 | | - |
---|
1524 | | -static int bpf_object__validate(struct bpf_object *obj, bool needs_kver) |
---|
1525 | | -{ |
---|
1526 | | - if (needs_kver && obj->kern_version == 0) { |
---|
1527 | | - pr_warning("%s doesn't provide kernel version\n", |
---|
1528 | | - obj->path); |
---|
1529 | | - return -LIBBPF_ERRNO__KVERSION; |
---|
1530 | | - } |
---|
1531 | | - return 0; |
---|
1532 | | -} |
---|
| 6939 | +static const struct bpf_sec_def *find_sec_def(const char *sec_name); |
---|
1533 | 6940 | |
---|
1534 | 6941 | static struct bpf_object * |
---|
1535 | | -__bpf_object__open(const char *path, void *obj_buf, size_t obj_buf_sz, |
---|
1536 | | - bool needs_kver) |
---|
| 6942 | +__bpf_object__open(const char *path, const void *obj_buf, size_t obj_buf_sz, |
---|
| 6943 | + const struct bpf_object_open_opts *opts) |
---|
1537 | 6944 | { |
---|
| 6945 | + const char *obj_name, *kconfig; |
---|
| 6946 | + struct bpf_program *prog; |
---|
1538 | 6947 | struct bpf_object *obj; |
---|
| 6948 | + char tmp_name[64]; |
---|
1539 | 6949 | int err; |
---|
1540 | 6950 | |
---|
1541 | 6951 | if (elf_version(EV_CURRENT) == EV_NONE) { |
---|
1542 | | - pr_warning("failed to init libelf for %s\n", path); |
---|
| 6952 | + pr_warn("failed to init libelf for %s\n", |
---|
| 6953 | + path ? : "(mem buf)"); |
---|
1543 | 6954 | return ERR_PTR(-LIBBPF_ERRNO__LIBELF); |
---|
1544 | 6955 | } |
---|
1545 | 6956 | |
---|
1546 | | - obj = bpf_object__new(path, obj_buf, obj_buf_sz); |
---|
| 6957 | + if (!OPTS_VALID(opts, bpf_object_open_opts)) |
---|
| 6958 | + return ERR_PTR(-EINVAL); |
---|
| 6959 | + |
---|
| 6960 | + obj_name = OPTS_GET(opts, object_name, NULL); |
---|
| 6961 | + if (obj_buf) { |
---|
| 6962 | + if (!obj_name) { |
---|
| 6963 | + snprintf(tmp_name, sizeof(tmp_name), "%lx-%lx", |
---|
| 6964 | + (unsigned long)obj_buf, |
---|
| 6965 | + (unsigned long)obj_buf_sz); |
---|
| 6966 | + obj_name = tmp_name; |
---|
| 6967 | + } |
---|
| 6968 | + path = obj_name; |
---|
| 6969 | + pr_debug("loading object '%s' from buffer\n", obj_name); |
---|
| 6970 | + } |
---|
| 6971 | + |
---|
| 6972 | + obj = bpf_object__new(path, obj_buf, obj_buf_sz, obj_name); |
---|
1547 | 6973 | if (IS_ERR(obj)) |
---|
1548 | 6974 | return obj; |
---|
1549 | 6975 | |
---|
1550 | | - CHECK_ERR(bpf_object__elf_init(obj), err, out); |
---|
1551 | | - CHECK_ERR(bpf_object__check_endianness(obj), err, out); |
---|
1552 | | - CHECK_ERR(bpf_object__elf_collect(obj), err, out); |
---|
1553 | | - CHECK_ERR(bpf_object__collect_reloc(obj), err, out); |
---|
1554 | | - CHECK_ERR(bpf_object__validate(obj, needs_kver), err, out); |
---|
| 6976 | + kconfig = OPTS_GET(opts, kconfig, NULL); |
---|
| 6977 | + if (kconfig) { |
---|
| 6978 | + obj->kconfig = strdup(kconfig); |
---|
| 6979 | + if (!obj->kconfig) { |
---|
| 6980 | + err = -ENOMEM; |
---|
| 6981 | + goto out; |
---|
| 6982 | + } |
---|
| 6983 | + } |
---|
1555 | 6984 | |
---|
| 6985 | + err = bpf_object__elf_init(obj); |
---|
| 6986 | + err = err ? : bpf_object__check_endianness(obj); |
---|
| 6987 | + err = err ? : bpf_object__elf_collect(obj); |
---|
| 6988 | + err = err ? : bpf_object__collect_externs(obj); |
---|
| 6989 | + err = err ? : bpf_object__finalize_btf(obj); |
---|
| 6990 | + err = err ? : bpf_object__init_maps(obj, opts); |
---|
| 6991 | + err = err ? : bpf_object__collect_relos(obj); |
---|
| 6992 | + if (err) |
---|
| 6993 | + goto out; |
---|
1556 | 6994 | bpf_object__elf_finish(obj); |
---|
| 6995 | + |
---|
| 6996 | + bpf_object__for_each_program(prog, obj) { |
---|
| 6997 | + prog->sec_def = find_sec_def(prog->sec_name); |
---|
| 6998 | + if (!prog->sec_def) |
---|
| 6999 | + /* couldn't guess, but user might manually specify */ |
---|
| 7000 | + continue; |
---|
| 7001 | + |
---|
| 7002 | + if (prog->sec_def->is_sleepable) |
---|
| 7003 | + prog->prog_flags |= BPF_F_SLEEPABLE; |
---|
| 7004 | + bpf_program__set_type(prog, prog->sec_def->prog_type); |
---|
| 7005 | + bpf_program__set_expected_attach_type(prog, |
---|
| 7006 | + prog->sec_def->expected_attach_type); |
---|
| 7007 | + |
---|
| 7008 | + if (prog->sec_def->prog_type == BPF_PROG_TYPE_TRACING || |
---|
| 7009 | + prog->sec_def->prog_type == BPF_PROG_TYPE_EXT) |
---|
| 7010 | + prog->attach_prog_fd = OPTS_GET(opts, attach_prog_fd, 0); |
---|
| 7011 | + } |
---|
| 7012 | + |
---|
1557 | 7013 | return obj; |
---|
1558 | 7014 | out: |
---|
1559 | 7015 | bpf_object__close(obj); |
---|
1560 | 7016 | return ERR_PTR(err); |
---|
1561 | 7017 | } |
---|
1562 | 7018 | |
---|
1563 | | -struct bpf_object *bpf_object__open_xattr(struct bpf_object_open_attr *attr) |
---|
| 7019 | +static struct bpf_object * |
---|
| 7020 | +__bpf_object__open_xattr(struct bpf_object_open_attr *attr, int flags) |
---|
1564 | 7021 | { |
---|
| 7022 | + DECLARE_LIBBPF_OPTS(bpf_object_open_opts, opts, |
---|
| 7023 | + .relaxed_maps = flags & MAPS_RELAX_COMPAT, |
---|
| 7024 | + ); |
---|
| 7025 | + |
---|
1565 | 7026 | /* param validation */ |
---|
1566 | 7027 | if (!attr->file) |
---|
1567 | 7028 | return NULL; |
---|
1568 | 7029 | |
---|
1569 | 7030 | pr_debug("loading %s\n", attr->file); |
---|
| 7031 | + return __bpf_object__open(attr->file, NULL, 0, &opts); |
---|
| 7032 | +} |
---|
1570 | 7033 | |
---|
1571 | | - return __bpf_object__open(attr->file, NULL, 0, |
---|
1572 | | - bpf_prog_type__needs_kver(attr->prog_type)); |
---|
| 7034 | +struct bpf_object *bpf_object__open_xattr(struct bpf_object_open_attr *attr) |
---|
| 7035 | +{ |
---|
| 7036 | + return __bpf_object__open_xattr(attr, 0); |
---|
1573 | 7037 | } |
---|
1574 | 7038 | |
---|
1575 | 7039 | struct bpf_object *bpf_object__open(const char *path) |
---|
.. | .. |
---|
1582 | 7046 | return bpf_object__open_xattr(&attr); |
---|
1583 | 7047 | } |
---|
1584 | 7048 | |
---|
1585 | | -struct bpf_object *bpf_object__open_buffer(void *obj_buf, |
---|
1586 | | - size_t obj_buf_sz, |
---|
1587 | | - const char *name) |
---|
| 7049 | +struct bpf_object * |
---|
| 7050 | +bpf_object__open_file(const char *path, const struct bpf_object_open_opts *opts) |
---|
1588 | 7051 | { |
---|
1589 | | - char tmp_name[64]; |
---|
| 7052 | + if (!path) |
---|
| 7053 | + return ERR_PTR(-EINVAL); |
---|
1590 | 7054 | |
---|
1591 | | - /* param validation */ |
---|
1592 | | - if (!obj_buf || obj_buf_sz <= 0) |
---|
| 7055 | + pr_debug("loading %s\n", path); |
---|
| 7056 | + |
---|
| 7057 | + return __bpf_object__open(path, NULL, 0, opts); |
---|
| 7058 | +} |
---|
| 7059 | + |
---|
| 7060 | +struct bpf_object * |
---|
| 7061 | +bpf_object__open_mem(const void *obj_buf, size_t obj_buf_sz, |
---|
| 7062 | + const struct bpf_object_open_opts *opts) |
---|
| 7063 | +{ |
---|
| 7064 | + if (!obj_buf || obj_buf_sz == 0) |
---|
| 7065 | + return ERR_PTR(-EINVAL); |
---|
| 7066 | + |
---|
| 7067 | + return __bpf_object__open(NULL, obj_buf, obj_buf_sz, opts); |
---|
| 7068 | +} |
---|
| 7069 | + |
---|
| 7070 | +struct bpf_object * |
---|
| 7071 | +bpf_object__open_buffer(const void *obj_buf, size_t obj_buf_sz, |
---|
| 7072 | + const char *name) |
---|
| 7073 | +{ |
---|
| 7074 | + DECLARE_LIBBPF_OPTS(bpf_object_open_opts, opts, |
---|
| 7075 | + .object_name = name, |
---|
| 7076 | + /* wrong default, but backwards-compatible */ |
---|
| 7077 | + .relaxed_maps = true, |
---|
| 7078 | + ); |
---|
| 7079 | + |
---|
| 7080 | + /* returning NULL is wrong, but backwards-compatible */ |
---|
| 7081 | + if (!obj_buf || obj_buf_sz == 0) |
---|
1593 | 7082 | return NULL; |
---|
1594 | 7083 | |
---|
1595 | | - if (!name) { |
---|
1596 | | - snprintf(tmp_name, sizeof(tmp_name), "%lx-%lx", |
---|
1597 | | - (unsigned long)obj_buf, |
---|
1598 | | - (unsigned long)obj_buf_sz); |
---|
1599 | | - tmp_name[sizeof(tmp_name) - 1] = '\0'; |
---|
1600 | | - name = tmp_name; |
---|
1601 | | - } |
---|
1602 | | - pr_debug("loading object '%s' from buffer\n", |
---|
1603 | | - name); |
---|
1604 | | - |
---|
1605 | | - return __bpf_object__open(name, obj_buf, obj_buf_sz, true); |
---|
| 7084 | + return bpf_object__open_mem(obj_buf, obj_buf_sz, &opts); |
---|
1606 | 7085 | } |
---|
1607 | 7086 | |
---|
1608 | 7087 | int bpf_object__unload(struct bpf_object *obj) |
---|
.. | .. |
---|
1612 | 7091 | if (!obj) |
---|
1613 | 7092 | return -EINVAL; |
---|
1614 | 7093 | |
---|
1615 | | - for (i = 0; i < obj->nr_maps; i++) |
---|
| 7094 | + for (i = 0; i < obj->nr_maps; i++) { |
---|
1616 | 7095 | zclose(obj->maps[i].fd); |
---|
| 7096 | + if (obj->maps[i].st_ops) |
---|
| 7097 | + zfree(&obj->maps[i].st_ops->kern_vdata); |
---|
| 7098 | + } |
---|
1617 | 7099 | |
---|
1618 | 7100 | for (i = 0; i < obj->nr_programs; i++) |
---|
1619 | 7101 | bpf_program__unload(&obj->programs[i]); |
---|
.. | .. |
---|
1621 | 7103 | return 0; |
---|
1622 | 7104 | } |
---|
1623 | 7105 | |
---|
1624 | | -int bpf_object__load(struct bpf_object *obj) |
---|
| 7106 | +static int bpf_object__sanitize_maps(struct bpf_object *obj) |
---|
1625 | 7107 | { |
---|
1626 | | - int err; |
---|
| 7108 | + struct bpf_map *m; |
---|
1627 | 7109 | |
---|
| 7110 | + bpf_object__for_each_map(m, obj) { |
---|
| 7111 | + if (!bpf_map__is_internal(m)) |
---|
| 7112 | + continue; |
---|
| 7113 | + if (!kernel_supports(FEAT_GLOBAL_DATA)) { |
---|
| 7114 | + pr_warn("kernel doesn't support global data\n"); |
---|
| 7115 | + return -ENOTSUP; |
---|
| 7116 | + } |
---|
| 7117 | + if (!kernel_supports(FEAT_ARRAY_MMAP)) |
---|
| 7118 | + m->def.map_flags ^= BPF_F_MMAPABLE; |
---|
| 7119 | + } |
---|
| 7120 | + |
---|
| 7121 | + return 0; |
---|
| 7122 | +} |
---|
| 7123 | + |
---|
| 7124 | +static int bpf_object__read_kallsyms_file(struct bpf_object *obj) |
---|
| 7125 | +{ |
---|
| 7126 | + char sym_type, sym_name[500]; |
---|
| 7127 | + unsigned long long sym_addr; |
---|
| 7128 | + struct extern_desc *ext; |
---|
| 7129 | + int ret, err = 0; |
---|
| 7130 | + FILE *f; |
---|
| 7131 | + |
---|
| 7132 | + f = fopen("/proc/kallsyms", "r"); |
---|
| 7133 | + if (!f) { |
---|
| 7134 | + err = -errno; |
---|
| 7135 | + pr_warn("failed to open /proc/kallsyms: %d\n", err); |
---|
| 7136 | + return err; |
---|
| 7137 | + } |
---|
| 7138 | + |
---|
| 7139 | + while (true) { |
---|
| 7140 | + ret = fscanf(f, "%llx %c %499s%*[^\n]\n", |
---|
| 7141 | + &sym_addr, &sym_type, sym_name); |
---|
| 7142 | + if (ret == EOF && feof(f)) |
---|
| 7143 | + break; |
---|
| 7144 | + if (ret != 3) { |
---|
| 7145 | + pr_warn("failed to read kallsyms entry: %d\n", ret); |
---|
| 7146 | + err = -EINVAL; |
---|
| 7147 | + goto out; |
---|
| 7148 | + } |
---|
| 7149 | + |
---|
| 7150 | + ext = find_extern_by_name(obj, sym_name); |
---|
| 7151 | + if (!ext || ext->type != EXT_KSYM) |
---|
| 7152 | + continue; |
---|
| 7153 | + |
---|
| 7154 | + if (ext->is_set && ext->ksym.addr != sym_addr) { |
---|
| 7155 | + pr_warn("extern (ksym) '%s' resolution is ambiguous: 0x%llx or 0x%llx\n", |
---|
| 7156 | + sym_name, ext->ksym.addr, sym_addr); |
---|
| 7157 | + err = -EINVAL; |
---|
| 7158 | + goto out; |
---|
| 7159 | + } |
---|
| 7160 | + if (!ext->is_set) { |
---|
| 7161 | + ext->is_set = true; |
---|
| 7162 | + ext->ksym.addr = sym_addr; |
---|
| 7163 | + pr_debug("extern (ksym) %s=0x%llx\n", sym_name, sym_addr); |
---|
| 7164 | + } |
---|
| 7165 | + } |
---|
| 7166 | + |
---|
| 7167 | +out: |
---|
| 7168 | + fclose(f); |
---|
| 7169 | + return err; |
---|
| 7170 | +} |
---|
| 7171 | + |
---|
| 7172 | +static int bpf_object__resolve_ksyms_btf_id(struct bpf_object *obj) |
---|
| 7173 | +{ |
---|
| 7174 | + struct extern_desc *ext; |
---|
| 7175 | + int i, id; |
---|
| 7176 | + |
---|
| 7177 | + for (i = 0; i < obj->nr_extern; i++) { |
---|
| 7178 | + const struct btf_type *targ_var, *targ_type; |
---|
| 7179 | + __u32 targ_type_id, local_type_id; |
---|
| 7180 | + const char *targ_var_name; |
---|
| 7181 | + int ret; |
---|
| 7182 | + |
---|
| 7183 | + ext = &obj->externs[i]; |
---|
| 7184 | + if (ext->type != EXT_KSYM || !ext->ksym.type_id) |
---|
| 7185 | + continue; |
---|
| 7186 | + |
---|
| 7187 | + id = btf__find_by_name_kind(obj->btf_vmlinux, ext->name, |
---|
| 7188 | + BTF_KIND_VAR); |
---|
| 7189 | + if (id <= 0) { |
---|
| 7190 | + pr_warn("extern (ksym) '%s': failed to find BTF ID in vmlinux BTF.\n", |
---|
| 7191 | + ext->name); |
---|
| 7192 | + return -ESRCH; |
---|
| 7193 | + } |
---|
| 7194 | + |
---|
| 7195 | + /* find local type_id */ |
---|
| 7196 | + local_type_id = ext->ksym.type_id; |
---|
| 7197 | + |
---|
| 7198 | + /* find target type_id */ |
---|
| 7199 | + targ_var = btf__type_by_id(obj->btf_vmlinux, id); |
---|
| 7200 | + targ_var_name = btf__name_by_offset(obj->btf_vmlinux, |
---|
| 7201 | + targ_var->name_off); |
---|
| 7202 | + targ_type = skip_mods_and_typedefs(obj->btf_vmlinux, |
---|
| 7203 | + targ_var->type, |
---|
| 7204 | + &targ_type_id); |
---|
| 7205 | + |
---|
| 7206 | + ret = bpf_core_types_are_compat(obj->btf, local_type_id, |
---|
| 7207 | + obj->btf_vmlinux, targ_type_id); |
---|
| 7208 | + if (ret <= 0) { |
---|
| 7209 | + const struct btf_type *local_type; |
---|
| 7210 | + const char *targ_name, *local_name; |
---|
| 7211 | + |
---|
| 7212 | + local_type = btf__type_by_id(obj->btf, local_type_id); |
---|
| 7213 | + local_name = btf__name_by_offset(obj->btf, |
---|
| 7214 | + local_type->name_off); |
---|
| 7215 | + targ_name = btf__name_by_offset(obj->btf_vmlinux, |
---|
| 7216 | + targ_type->name_off); |
---|
| 7217 | + |
---|
| 7218 | + pr_warn("extern (ksym) '%s': incompatible types, expected [%d] %s %s, but kernel has [%d] %s %s\n", |
---|
| 7219 | + ext->name, local_type_id, |
---|
| 7220 | + btf_kind_str(local_type), local_name, targ_type_id, |
---|
| 7221 | + btf_kind_str(targ_type), targ_name); |
---|
| 7222 | + return -EINVAL; |
---|
| 7223 | + } |
---|
| 7224 | + |
---|
| 7225 | + ext->is_set = true; |
---|
| 7226 | + ext->ksym.vmlinux_btf_id = id; |
---|
| 7227 | + pr_debug("extern (ksym) '%s': resolved to [%d] %s %s\n", |
---|
| 7228 | + ext->name, id, btf_kind_str(targ_var), targ_var_name); |
---|
| 7229 | + } |
---|
| 7230 | + return 0; |
---|
| 7231 | +} |
---|
| 7232 | + |
---|
| 7233 | +static int bpf_object__resolve_externs(struct bpf_object *obj, |
---|
| 7234 | + const char *extra_kconfig) |
---|
| 7235 | +{ |
---|
| 7236 | + bool need_config = false, need_kallsyms = false; |
---|
| 7237 | + bool need_vmlinux_btf = false; |
---|
| 7238 | + struct extern_desc *ext; |
---|
| 7239 | + void *kcfg_data = NULL; |
---|
| 7240 | + int err, i; |
---|
| 7241 | + |
---|
| 7242 | + if (obj->nr_extern == 0) |
---|
| 7243 | + return 0; |
---|
| 7244 | + |
---|
| 7245 | + if (obj->kconfig_map_idx >= 0) |
---|
| 7246 | + kcfg_data = obj->maps[obj->kconfig_map_idx].mmaped; |
---|
| 7247 | + |
---|
| 7248 | + for (i = 0; i < obj->nr_extern; i++) { |
---|
| 7249 | + ext = &obj->externs[i]; |
---|
| 7250 | + |
---|
| 7251 | + if (ext->type == EXT_KCFG && |
---|
| 7252 | + strcmp(ext->name, "LINUX_KERNEL_VERSION") == 0) { |
---|
| 7253 | + void *ext_val = kcfg_data + ext->kcfg.data_off; |
---|
| 7254 | + __u32 kver = get_kernel_version(); |
---|
| 7255 | + |
---|
| 7256 | + if (!kver) { |
---|
| 7257 | + pr_warn("failed to get kernel version\n"); |
---|
| 7258 | + return -EINVAL; |
---|
| 7259 | + } |
---|
| 7260 | + err = set_kcfg_value_num(ext, ext_val, kver); |
---|
| 7261 | + if (err) |
---|
| 7262 | + return err; |
---|
| 7263 | + pr_debug("extern (kcfg) %s=0x%x\n", ext->name, kver); |
---|
| 7264 | + } else if (ext->type == EXT_KCFG && |
---|
| 7265 | + strncmp(ext->name, "CONFIG_", 7) == 0) { |
---|
| 7266 | + need_config = true; |
---|
| 7267 | + } else if (ext->type == EXT_KSYM) { |
---|
| 7268 | + if (ext->ksym.type_id) |
---|
| 7269 | + need_vmlinux_btf = true; |
---|
| 7270 | + else |
---|
| 7271 | + need_kallsyms = true; |
---|
| 7272 | + } else { |
---|
| 7273 | + pr_warn("unrecognized extern '%s'\n", ext->name); |
---|
| 7274 | + return -EINVAL; |
---|
| 7275 | + } |
---|
| 7276 | + } |
---|
| 7277 | + if (need_config && extra_kconfig) { |
---|
| 7278 | + err = bpf_object__read_kconfig_mem(obj, extra_kconfig, kcfg_data); |
---|
| 7279 | + if (err) |
---|
| 7280 | + return -EINVAL; |
---|
| 7281 | + need_config = false; |
---|
| 7282 | + for (i = 0; i < obj->nr_extern; i++) { |
---|
| 7283 | + ext = &obj->externs[i]; |
---|
| 7284 | + if (ext->type == EXT_KCFG && !ext->is_set) { |
---|
| 7285 | + need_config = true; |
---|
| 7286 | + break; |
---|
| 7287 | + } |
---|
| 7288 | + } |
---|
| 7289 | + } |
---|
| 7290 | + if (need_config) { |
---|
| 7291 | + err = bpf_object__read_kconfig_file(obj, kcfg_data); |
---|
| 7292 | + if (err) |
---|
| 7293 | + return -EINVAL; |
---|
| 7294 | + } |
---|
| 7295 | + if (need_kallsyms) { |
---|
| 7296 | + err = bpf_object__read_kallsyms_file(obj); |
---|
| 7297 | + if (err) |
---|
| 7298 | + return -EINVAL; |
---|
| 7299 | + } |
---|
| 7300 | + if (need_vmlinux_btf) { |
---|
| 7301 | + err = bpf_object__resolve_ksyms_btf_id(obj); |
---|
| 7302 | + if (err) |
---|
| 7303 | + return -EINVAL; |
---|
| 7304 | + } |
---|
| 7305 | + for (i = 0; i < obj->nr_extern; i++) { |
---|
| 7306 | + ext = &obj->externs[i]; |
---|
| 7307 | + |
---|
| 7308 | + if (!ext->is_set && !ext->is_weak) { |
---|
| 7309 | + pr_warn("extern %s (strong) not resolved\n", ext->name); |
---|
| 7310 | + return -ESRCH; |
---|
| 7311 | + } else if (!ext->is_set) { |
---|
| 7312 | + pr_debug("extern %s (weak) not resolved, defaulting to zero\n", |
---|
| 7313 | + ext->name); |
---|
| 7314 | + } |
---|
| 7315 | + } |
---|
| 7316 | + |
---|
| 7317 | + return 0; |
---|
| 7318 | +} |
---|
| 7319 | + |
---|
| 7320 | +int bpf_object__load_xattr(struct bpf_object_load_attr *attr) |
---|
| 7321 | +{ |
---|
| 7322 | + struct bpf_object *obj; |
---|
| 7323 | + int err, i; |
---|
| 7324 | + |
---|
| 7325 | + if (!attr) |
---|
| 7326 | + return -EINVAL; |
---|
| 7327 | + obj = attr->obj; |
---|
1628 | 7328 | if (!obj) |
---|
1629 | 7329 | return -EINVAL; |
---|
1630 | 7330 | |
---|
1631 | 7331 | if (obj->loaded) { |
---|
1632 | | - pr_warning("object should not be loaded twice\n"); |
---|
| 7332 | + pr_warn("object '%s': load can't be attempted twice\n", obj->name); |
---|
1633 | 7333 | return -EINVAL; |
---|
1634 | 7334 | } |
---|
1635 | 7335 | |
---|
1636 | | - obj->loaded = true; |
---|
| 7336 | + err = bpf_object__probe_loading(obj); |
---|
| 7337 | + err = err ? : bpf_object__load_vmlinux_btf(obj); |
---|
| 7338 | + err = err ? : bpf_object__resolve_externs(obj, obj->kconfig); |
---|
| 7339 | + err = err ? : bpf_object__sanitize_and_load_btf(obj); |
---|
| 7340 | + err = err ? : bpf_object__sanitize_maps(obj); |
---|
| 7341 | + err = err ? : bpf_object__init_kern_struct_ops_maps(obj); |
---|
| 7342 | + err = err ? : bpf_object__create_maps(obj); |
---|
| 7343 | + err = err ? : bpf_object__relocate(obj, attr->target_btf_path); |
---|
| 7344 | + err = err ? : bpf_object__load_progs(obj, attr->log_level); |
---|
1637 | 7345 | |
---|
1638 | | - CHECK_ERR(bpf_object__create_maps(obj), err, out); |
---|
1639 | | - CHECK_ERR(bpf_object__relocate(obj), err, out); |
---|
1640 | | - CHECK_ERR(bpf_object__load_progs(obj), err, out); |
---|
| 7346 | + btf__free(obj->btf_vmlinux); |
---|
| 7347 | + obj->btf_vmlinux = NULL; |
---|
| 7348 | + |
---|
| 7349 | + obj->loaded = true; /* doesn't matter if successfully or not */ |
---|
| 7350 | + |
---|
| 7351 | + if (err) |
---|
| 7352 | + goto out; |
---|
1641 | 7353 | |
---|
1642 | 7354 | return 0; |
---|
1643 | 7355 | out: |
---|
| 7356 | + /* unpin any maps that were auto-pinned during load */ |
---|
| 7357 | + for (i = 0; i < obj->nr_maps; i++) |
---|
| 7358 | + if (obj->maps[i].pinned && !obj->maps[i].reused) |
---|
| 7359 | + bpf_map__unpin(&obj->maps[i], NULL); |
---|
| 7360 | + |
---|
1644 | 7361 | bpf_object__unload(obj); |
---|
1645 | | - pr_warning("failed to load object '%s'\n", obj->path); |
---|
| 7362 | + pr_warn("failed to load object '%s'\n", obj->path); |
---|
| 7363 | + return err; |
---|
| 7364 | +} |
---|
| 7365 | + |
---|
| 7366 | +int bpf_object__load(struct bpf_object *obj) |
---|
| 7367 | +{ |
---|
| 7368 | + struct bpf_object_load_attr attr = { |
---|
| 7369 | + .obj = obj, |
---|
| 7370 | + }; |
---|
| 7371 | + |
---|
| 7372 | + return bpf_object__load_xattr(&attr); |
---|
| 7373 | +} |
---|
| 7374 | + |
---|
| 7375 | +static int make_parent_dir(const char *path) |
---|
| 7376 | +{ |
---|
| 7377 | + char *cp, errmsg[STRERR_BUFSIZE]; |
---|
| 7378 | + char *dname, *dir; |
---|
| 7379 | + int err = 0; |
---|
| 7380 | + |
---|
| 7381 | + dname = strdup(path); |
---|
| 7382 | + if (dname == NULL) |
---|
| 7383 | + return -ENOMEM; |
---|
| 7384 | + |
---|
| 7385 | + dir = dirname(dname); |
---|
| 7386 | + if (mkdir(dir, 0700) && errno != EEXIST) |
---|
| 7387 | + err = -errno; |
---|
| 7388 | + |
---|
| 7389 | + free(dname); |
---|
| 7390 | + if (err) { |
---|
| 7391 | + cp = libbpf_strerror_r(-err, errmsg, sizeof(errmsg)); |
---|
| 7392 | + pr_warn("failed to mkdir %s: %s\n", path, cp); |
---|
| 7393 | + } |
---|
1646 | 7394 | return err; |
---|
1647 | 7395 | } |
---|
1648 | 7396 | |
---|
.. | .. |
---|
1662 | 7410 | |
---|
1663 | 7411 | dir = dirname(dname); |
---|
1664 | 7412 | if (statfs(dir, &st_fs)) { |
---|
1665 | | - cp = str_error(errno, errmsg, sizeof(errmsg)); |
---|
1666 | | - pr_warning("failed to statfs %s: %s\n", dir, cp); |
---|
| 7413 | + cp = libbpf_strerror_r(errno, errmsg, sizeof(errmsg)); |
---|
| 7414 | + pr_warn("failed to statfs %s: %s\n", dir, cp); |
---|
1667 | 7415 | err = -errno; |
---|
1668 | 7416 | } |
---|
1669 | 7417 | free(dname); |
---|
1670 | 7418 | |
---|
1671 | 7419 | if (!err && st_fs.f_type != BPF_FS_MAGIC) { |
---|
1672 | | - pr_warning("specified path %s is not on BPF FS\n", path); |
---|
| 7420 | + pr_warn("specified path %s is not on BPF FS\n", path); |
---|
1673 | 7421 | err = -EINVAL; |
---|
1674 | 7422 | } |
---|
1675 | 7423 | |
---|
.. | .. |
---|
1682 | 7430 | char *cp, errmsg[STRERR_BUFSIZE]; |
---|
1683 | 7431 | int err; |
---|
1684 | 7432 | |
---|
| 7433 | + err = make_parent_dir(path); |
---|
| 7434 | + if (err) |
---|
| 7435 | + return err; |
---|
| 7436 | + |
---|
1685 | 7437 | err = check_path(path); |
---|
1686 | 7438 | if (err) |
---|
1687 | 7439 | return err; |
---|
1688 | 7440 | |
---|
1689 | 7441 | if (prog == NULL) { |
---|
1690 | | - pr_warning("invalid program pointer\n"); |
---|
| 7442 | + pr_warn("invalid program pointer\n"); |
---|
1691 | 7443 | return -EINVAL; |
---|
1692 | 7444 | } |
---|
1693 | 7445 | |
---|
1694 | 7446 | if (instance < 0 || instance >= prog->instances.nr) { |
---|
1695 | | - pr_warning("invalid prog instance %d of prog %s (max %d)\n", |
---|
1696 | | - instance, prog->section_name, prog->instances.nr); |
---|
| 7447 | + pr_warn("invalid prog instance %d of prog %s (max %d)\n", |
---|
| 7448 | + instance, prog->name, prog->instances.nr); |
---|
1697 | 7449 | return -EINVAL; |
---|
1698 | 7450 | } |
---|
1699 | 7451 | |
---|
1700 | 7452 | if (bpf_obj_pin(prog->instances.fds[instance], path)) { |
---|
1701 | | - cp = str_error(errno, errmsg, sizeof(errmsg)); |
---|
1702 | | - pr_warning("failed to pin program: %s\n", cp); |
---|
1703 | | - return -errno; |
---|
| 7453 | + err = -errno; |
---|
| 7454 | + cp = libbpf_strerror_r(err, errmsg, sizeof(errmsg)); |
---|
| 7455 | + pr_warn("failed to pin program: %s\n", cp); |
---|
| 7456 | + return err; |
---|
1704 | 7457 | } |
---|
1705 | 7458 | pr_debug("pinned program '%s'\n", path); |
---|
1706 | 7459 | |
---|
1707 | 7460 | return 0; |
---|
1708 | 7461 | } |
---|
1709 | 7462 | |
---|
1710 | | -static int make_dir(const char *path) |
---|
| 7463 | +int bpf_program__unpin_instance(struct bpf_program *prog, const char *path, |
---|
| 7464 | + int instance) |
---|
1711 | 7465 | { |
---|
1712 | | - char *cp, errmsg[STRERR_BUFSIZE]; |
---|
1713 | | - int err = 0; |
---|
| 7466 | + int err; |
---|
1714 | 7467 | |
---|
1715 | | - if (mkdir(path, 0700) && errno != EEXIST) |
---|
1716 | | - err = -errno; |
---|
| 7468 | + err = check_path(path); |
---|
| 7469 | + if (err) |
---|
| 7470 | + return err; |
---|
1717 | 7471 | |
---|
1718 | | - if (err) { |
---|
1719 | | - cp = str_error(-err, errmsg, sizeof(errmsg)); |
---|
1720 | | - pr_warning("failed to mkdir %s: %s\n", path, cp); |
---|
| 7472 | + if (prog == NULL) { |
---|
| 7473 | + pr_warn("invalid program pointer\n"); |
---|
| 7474 | + return -EINVAL; |
---|
1721 | 7475 | } |
---|
1722 | | - return err; |
---|
| 7476 | + |
---|
| 7477 | + if (instance < 0 || instance >= prog->instances.nr) { |
---|
| 7478 | + pr_warn("invalid prog instance %d of prog %s (max %d)\n", |
---|
| 7479 | + instance, prog->name, prog->instances.nr); |
---|
| 7480 | + return -EINVAL; |
---|
| 7481 | + } |
---|
| 7482 | + |
---|
| 7483 | + err = unlink(path); |
---|
| 7484 | + if (err != 0) |
---|
| 7485 | + return -errno; |
---|
| 7486 | + pr_debug("unpinned program '%s'\n", path); |
---|
| 7487 | + |
---|
| 7488 | + return 0; |
---|
1723 | 7489 | } |
---|
1724 | 7490 | |
---|
1725 | 7491 | int bpf_program__pin(struct bpf_program *prog, const char *path) |
---|
| 7492 | +{ |
---|
| 7493 | + int i, err; |
---|
| 7494 | + |
---|
| 7495 | + err = make_parent_dir(path); |
---|
| 7496 | + if (err) |
---|
| 7497 | + return err; |
---|
| 7498 | + |
---|
| 7499 | + err = check_path(path); |
---|
| 7500 | + if (err) |
---|
| 7501 | + return err; |
---|
| 7502 | + |
---|
| 7503 | + if (prog == NULL) { |
---|
| 7504 | + pr_warn("invalid program pointer\n"); |
---|
| 7505 | + return -EINVAL; |
---|
| 7506 | + } |
---|
| 7507 | + |
---|
| 7508 | + if (prog->instances.nr <= 0) { |
---|
| 7509 | + pr_warn("no instances of prog %s to pin\n", prog->name); |
---|
| 7510 | + return -EINVAL; |
---|
| 7511 | + } |
---|
| 7512 | + |
---|
| 7513 | + if (prog->instances.nr == 1) { |
---|
| 7514 | + /* don't create subdirs when pinning single instance */ |
---|
| 7515 | + return bpf_program__pin_instance(prog, path, 0); |
---|
| 7516 | + } |
---|
| 7517 | + |
---|
| 7518 | + for (i = 0; i < prog->instances.nr; i++) { |
---|
| 7519 | + char buf[PATH_MAX]; |
---|
| 7520 | + int len; |
---|
| 7521 | + |
---|
| 7522 | + len = snprintf(buf, PATH_MAX, "%s/%d", path, i); |
---|
| 7523 | + if (len < 0) { |
---|
| 7524 | + err = -EINVAL; |
---|
| 7525 | + goto err_unpin; |
---|
| 7526 | + } else if (len >= PATH_MAX) { |
---|
| 7527 | + err = -ENAMETOOLONG; |
---|
| 7528 | + goto err_unpin; |
---|
| 7529 | + } |
---|
| 7530 | + |
---|
| 7531 | + err = bpf_program__pin_instance(prog, buf, i); |
---|
| 7532 | + if (err) |
---|
| 7533 | + goto err_unpin; |
---|
| 7534 | + } |
---|
| 7535 | + |
---|
| 7536 | + return 0; |
---|
| 7537 | + |
---|
| 7538 | +err_unpin: |
---|
| 7539 | + for (i = i - 1; i >= 0; i--) { |
---|
| 7540 | + char buf[PATH_MAX]; |
---|
| 7541 | + int len; |
---|
| 7542 | + |
---|
| 7543 | + len = snprintf(buf, PATH_MAX, "%s/%d", path, i); |
---|
| 7544 | + if (len < 0) |
---|
| 7545 | + continue; |
---|
| 7546 | + else if (len >= PATH_MAX) |
---|
| 7547 | + continue; |
---|
| 7548 | + |
---|
| 7549 | + bpf_program__unpin_instance(prog, buf, i); |
---|
| 7550 | + } |
---|
| 7551 | + |
---|
| 7552 | + rmdir(path); |
---|
| 7553 | + |
---|
| 7554 | + return err; |
---|
| 7555 | +} |
---|
| 7556 | + |
---|
| 7557 | +int bpf_program__unpin(struct bpf_program *prog, const char *path) |
---|
1726 | 7558 | { |
---|
1727 | 7559 | int i, err; |
---|
1728 | 7560 | |
---|
.. | .. |
---|
1731 | 7563 | return err; |
---|
1732 | 7564 | |
---|
1733 | 7565 | if (prog == NULL) { |
---|
1734 | | - pr_warning("invalid program pointer\n"); |
---|
| 7566 | + pr_warn("invalid program pointer\n"); |
---|
1735 | 7567 | return -EINVAL; |
---|
1736 | 7568 | } |
---|
1737 | 7569 | |
---|
1738 | 7570 | if (prog->instances.nr <= 0) { |
---|
1739 | | - pr_warning("no instances of prog %s to pin\n", |
---|
1740 | | - prog->section_name); |
---|
| 7571 | + pr_warn("no instances of prog %s to pin\n", prog->name); |
---|
1741 | 7572 | return -EINVAL; |
---|
1742 | 7573 | } |
---|
1743 | 7574 | |
---|
1744 | | - err = make_dir(path); |
---|
1745 | | - if (err) |
---|
1746 | | - return err; |
---|
| 7575 | + if (prog->instances.nr == 1) { |
---|
| 7576 | + /* don't create subdirs when pinning single instance */ |
---|
| 7577 | + return bpf_program__unpin_instance(prog, path, 0); |
---|
| 7578 | + } |
---|
1747 | 7579 | |
---|
1748 | 7580 | for (i = 0; i < prog->instances.nr; i++) { |
---|
1749 | 7581 | char buf[PATH_MAX]; |
---|
.. | .. |
---|
1755 | 7587 | else if (len >= PATH_MAX) |
---|
1756 | 7588 | return -ENAMETOOLONG; |
---|
1757 | 7589 | |
---|
1758 | | - err = bpf_program__pin_instance(prog, buf, i); |
---|
| 7590 | + err = bpf_program__unpin_instance(prog, buf, i); |
---|
1759 | 7591 | if (err) |
---|
1760 | 7592 | return err; |
---|
1761 | 7593 | } |
---|
| 7594 | + |
---|
| 7595 | + err = rmdir(path); |
---|
| 7596 | + if (err) |
---|
| 7597 | + return -errno; |
---|
1762 | 7598 | |
---|
1763 | 7599 | return 0; |
---|
1764 | 7600 | } |
---|
.. | .. |
---|
1768 | 7604 | char *cp, errmsg[STRERR_BUFSIZE]; |
---|
1769 | 7605 | int err; |
---|
1770 | 7606 | |
---|
| 7607 | + if (map == NULL) { |
---|
| 7608 | + pr_warn("invalid map pointer\n"); |
---|
| 7609 | + return -EINVAL; |
---|
| 7610 | + } |
---|
| 7611 | + |
---|
| 7612 | + if (map->pin_path) { |
---|
| 7613 | + if (path && strcmp(path, map->pin_path)) { |
---|
| 7614 | + pr_warn("map '%s' already has pin path '%s' different from '%s'\n", |
---|
| 7615 | + bpf_map__name(map), map->pin_path, path); |
---|
| 7616 | + return -EINVAL; |
---|
| 7617 | + } else if (map->pinned) { |
---|
| 7618 | + pr_debug("map '%s' already pinned at '%s'; not re-pinning\n", |
---|
| 7619 | + bpf_map__name(map), map->pin_path); |
---|
| 7620 | + return 0; |
---|
| 7621 | + } |
---|
| 7622 | + } else { |
---|
| 7623 | + if (!path) { |
---|
| 7624 | + pr_warn("missing a path to pin map '%s' at\n", |
---|
| 7625 | + bpf_map__name(map)); |
---|
| 7626 | + return -EINVAL; |
---|
| 7627 | + } else if (map->pinned) { |
---|
| 7628 | + pr_warn("map '%s' already pinned\n", bpf_map__name(map)); |
---|
| 7629 | + return -EEXIST; |
---|
| 7630 | + } |
---|
| 7631 | + |
---|
| 7632 | + map->pin_path = strdup(path); |
---|
| 7633 | + if (!map->pin_path) { |
---|
| 7634 | + err = -errno; |
---|
| 7635 | + goto out_err; |
---|
| 7636 | + } |
---|
| 7637 | + } |
---|
| 7638 | + |
---|
| 7639 | + err = make_parent_dir(map->pin_path); |
---|
| 7640 | + if (err) |
---|
| 7641 | + return err; |
---|
| 7642 | + |
---|
| 7643 | + err = check_path(map->pin_path); |
---|
| 7644 | + if (err) |
---|
| 7645 | + return err; |
---|
| 7646 | + |
---|
| 7647 | + if (bpf_obj_pin(map->fd, map->pin_path)) { |
---|
| 7648 | + err = -errno; |
---|
| 7649 | + goto out_err; |
---|
| 7650 | + } |
---|
| 7651 | + |
---|
| 7652 | + map->pinned = true; |
---|
| 7653 | + pr_debug("pinned map '%s'\n", map->pin_path); |
---|
| 7654 | + |
---|
| 7655 | + return 0; |
---|
| 7656 | + |
---|
| 7657 | +out_err: |
---|
| 7658 | + cp = libbpf_strerror_r(-err, errmsg, sizeof(errmsg)); |
---|
| 7659 | + pr_warn("failed to pin map: %s\n", cp); |
---|
| 7660 | + return err; |
---|
| 7661 | +} |
---|
| 7662 | + |
---|
| 7663 | +int bpf_map__unpin(struct bpf_map *map, const char *path) |
---|
| 7664 | +{ |
---|
| 7665 | + int err; |
---|
| 7666 | + |
---|
| 7667 | + if (map == NULL) { |
---|
| 7668 | + pr_warn("invalid map pointer\n"); |
---|
| 7669 | + return -EINVAL; |
---|
| 7670 | + } |
---|
| 7671 | + |
---|
| 7672 | + if (map->pin_path) { |
---|
| 7673 | + if (path && strcmp(path, map->pin_path)) { |
---|
| 7674 | + pr_warn("map '%s' already has pin path '%s' different from '%s'\n", |
---|
| 7675 | + bpf_map__name(map), map->pin_path, path); |
---|
| 7676 | + return -EINVAL; |
---|
| 7677 | + } |
---|
| 7678 | + path = map->pin_path; |
---|
| 7679 | + } else if (!path) { |
---|
| 7680 | + pr_warn("no path to unpin map '%s' from\n", |
---|
| 7681 | + bpf_map__name(map)); |
---|
| 7682 | + return -EINVAL; |
---|
| 7683 | + } |
---|
| 7684 | + |
---|
1771 | 7685 | err = check_path(path); |
---|
1772 | 7686 | if (err) |
---|
1773 | 7687 | return err; |
---|
1774 | 7688 | |
---|
1775 | | - if (map == NULL) { |
---|
1776 | | - pr_warning("invalid map pointer\n"); |
---|
1777 | | - return -EINVAL; |
---|
1778 | | - } |
---|
1779 | | - |
---|
1780 | | - if (bpf_obj_pin(map->fd, path)) { |
---|
1781 | | - cp = str_error(errno, errmsg, sizeof(errmsg)); |
---|
1782 | | - pr_warning("failed to pin map: %s\n", cp); |
---|
| 7689 | + err = unlink(path); |
---|
| 7690 | + if (err != 0) |
---|
1783 | 7691 | return -errno; |
---|
1784 | | - } |
---|
1785 | 7692 | |
---|
1786 | | - pr_debug("pinned map '%s'\n", path); |
---|
| 7693 | + map->pinned = false; |
---|
| 7694 | + pr_debug("unpinned map '%s' from '%s'\n", bpf_map__name(map), path); |
---|
| 7695 | + |
---|
1787 | 7696 | return 0; |
---|
1788 | 7697 | } |
---|
1789 | 7698 | |
---|
1790 | | -int bpf_object__pin(struct bpf_object *obj, const char *path) |
---|
| 7699 | +int bpf_map__set_pin_path(struct bpf_map *map, const char *path) |
---|
1791 | 7700 | { |
---|
1792 | | - struct bpf_program *prog; |
---|
| 7701 | + char *new = NULL; |
---|
| 7702 | + |
---|
| 7703 | + if (path) { |
---|
| 7704 | + new = strdup(path); |
---|
| 7705 | + if (!new) |
---|
| 7706 | + return -errno; |
---|
| 7707 | + } |
---|
| 7708 | + |
---|
| 7709 | + free(map->pin_path); |
---|
| 7710 | + map->pin_path = new; |
---|
| 7711 | + return 0; |
---|
| 7712 | +} |
---|
| 7713 | + |
---|
| 7714 | +const char *bpf_map__get_pin_path(const struct bpf_map *map) |
---|
| 7715 | +{ |
---|
| 7716 | + return map->pin_path; |
---|
| 7717 | +} |
---|
| 7718 | + |
---|
| 7719 | +bool bpf_map__is_pinned(const struct bpf_map *map) |
---|
| 7720 | +{ |
---|
| 7721 | + return map->pinned; |
---|
| 7722 | +} |
---|
| 7723 | + |
---|
| 7724 | +static void sanitize_pin_path(char *s) |
---|
| 7725 | +{ |
---|
| 7726 | + /* bpffs disallows periods in path names */ |
---|
| 7727 | + while (*s) { |
---|
| 7728 | + if (*s == '.') |
---|
| 7729 | + *s = '_'; |
---|
| 7730 | + s++; |
---|
| 7731 | + } |
---|
| 7732 | +} |
---|
| 7733 | + |
---|
| 7734 | +int bpf_object__pin_maps(struct bpf_object *obj, const char *path) |
---|
| 7735 | +{ |
---|
1793 | 7736 | struct bpf_map *map; |
---|
1794 | 7737 | int err; |
---|
1795 | 7738 | |
---|
.. | .. |
---|
1797 | 7740 | return -ENOENT; |
---|
1798 | 7741 | |
---|
1799 | 7742 | if (!obj->loaded) { |
---|
1800 | | - pr_warning("object not yet loaded; load it first\n"); |
---|
| 7743 | + pr_warn("object not yet loaded; load it first\n"); |
---|
1801 | 7744 | return -ENOENT; |
---|
1802 | 7745 | } |
---|
1803 | 7746 | |
---|
1804 | | - err = make_dir(path); |
---|
1805 | | - if (err) |
---|
1806 | | - return err; |
---|
1807 | | - |
---|
1808 | | - bpf_map__for_each(map, obj) { |
---|
| 7747 | + bpf_object__for_each_map(map, obj) { |
---|
| 7748 | + char *pin_path = NULL; |
---|
1809 | 7749 | char buf[PATH_MAX]; |
---|
1810 | | - int len; |
---|
1811 | 7750 | |
---|
1812 | | - len = snprintf(buf, PATH_MAX, "%s/%s", path, |
---|
1813 | | - bpf_map__name(map)); |
---|
1814 | | - if (len < 0) |
---|
1815 | | - return -EINVAL; |
---|
1816 | | - else if (len >= PATH_MAX) |
---|
1817 | | - return -ENAMETOOLONG; |
---|
| 7751 | + if (path) { |
---|
| 7752 | + int len; |
---|
1818 | 7753 | |
---|
1819 | | - err = bpf_map__pin(map, buf); |
---|
| 7754 | + len = snprintf(buf, PATH_MAX, "%s/%s", path, |
---|
| 7755 | + bpf_map__name(map)); |
---|
| 7756 | + if (len < 0) { |
---|
| 7757 | + err = -EINVAL; |
---|
| 7758 | + goto err_unpin_maps; |
---|
| 7759 | + } else if (len >= PATH_MAX) { |
---|
| 7760 | + err = -ENAMETOOLONG; |
---|
| 7761 | + goto err_unpin_maps; |
---|
| 7762 | + } |
---|
| 7763 | + sanitize_pin_path(buf); |
---|
| 7764 | + pin_path = buf; |
---|
| 7765 | + } else if (!map->pin_path) { |
---|
| 7766 | + continue; |
---|
| 7767 | + } |
---|
| 7768 | + |
---|
| 7769 | + err = bpf_map__pin(map, pin_path); |
---|
1820 | 7770 | if (err) |
---|
1821 | | - return err; |
---|
| 7771 | + goto err_unpin_maps; |
---|
1822 | 7772 | } |
---|
1823 | 7773 | |
---|
1824 | | - bpf_object__for_each_program(prog, obj) { |
---|
| 7774 | + return 0; |
---|
| 7775 | + |
---|
| 7776 | +err_unpin_maps: |
---|
| 7777 | + while ((map = bpf_map__prev(map, obj))) { |
---|
| 7778 | + if (!map->pin_path) |
---|
| 7779 | + continue; |
---|
| 7780 | + |
---|
| 7781 | + bpf_map__unpin(map, NULL); |
---|
| 7782 | + } |
---|
| 7783 | + |
---|
| 7784 | + return err; |
---|
| 7785 | +} |
---|
| 7786 | + |
---|
| 7787 | +int bpf_object__unpin_maps(struct bpf_object *obj, const char *path) |
---|
| 7788 | +{ |
---|
| 7789 | + struct bpf_map *map; |
---|
| 7790 | + int err; |
---|
| 7791 | + |
---|
| 7792 | + if (!obj) |
---|
| 7793 | + return -ENOENT; |
---|
| 7794 | + |
---|
| 7795 | + bpf_object__for_each_map(map, obj) { |
---|
| 7796 | + char *pin_path = NULL; |
---|
1825 | 7797 | char buf[PATH_MAX]; |
---|
1826 | | - int len; |
---|
1827 | 7798 | |
---|
1828 | | - len = snprintf(buf, PATH_MAX, "%s/%s", path, |
---|
1829 | | - prog->section_name); |
---|
1830 | | - if (len < 0) |
---|
1831 | | - return -EINVAL; |
---|
1832 | | - else if (len >= PATH_MAX) |
---|
1833 | | - return -ENAMETOOLONG; |
---|
| 7799 | + if (path) { |
---|
| 7800 | + int len; |
---|
1834 | 7801 | |
---|
1835 | | - err = bpf_program__pin(prog, buf); |
---|
| 7802 | + len = snprintf(buf, PATH_MAX, "%s/%s", path, |
---|
| 7803 | + bpf_map__name(map)); |
---|
| 7804 | + if (len < 0) |
---|
| 7805 | + return -EINVAL; |
---|
| 7806 | + else if (len >= PATH_MAX) |
---|
| 7807 | + return -ENAMETOOLONG; |
---|
| 7808 | + sanitize_pin_path(buf); |
---|
| 7809 | + pin_path = buf; |
---|
| 7810 | + } else if (!map->pin_path) { |
---|
| 7811 | + continue; |
---|
| 7812 | + } |
---|
| 7813 | + |
---|
| 7814 | + err = bpf_map__unpin(map, pin_path); |
---|
1836 | 7815 | if (err) |
---|
1837 | 7816 | return err; |
---|
1838 | 7817 | } |
---|
.. | .. |
---|
1840 | 7819 | return 0; |
---|
1841 | 7820 | } |
---|
1842 | 7821 | |
---|
| 7822 | +int bpf_object__pin_programs(struct bpf_object *obj, const char *path) |
---|
| 7823 | +{ |
---|
| 7824 | + struct bpf_program *prog; |
---|
| 7825 | + int err; |
---|
| 7826 | + |
---|
| 7827 | + if (!obj) |
---|
| 7828 | + return -ENOENT; |
---|
| 7829 | + |
---|
| 7830 | + if (!obj->loaded) { |
---|
| 7831 | + pr_warn("object not yet loaded; load it first\n"); |
---|
| 7832 | + return -ENOENT; |
---|
| 7833 | + } |
---|
| 7834 | + |
---|
| 7835 | + bpf_object__for_each_program(prog, obj) { |
---|
| 7836 | + char buf[PATH_MAX]; |
---|
| 7837 | + int len; |
---|
| 7838 | + |
---|
| 7839 | + len = snprintf(buf, PATH_MAX, "%s/%s", path, |
---|
| 7840 | + prog->pin_name); |
---|
| 7841 | + if (len < 0) { |
---|
| 7842 | + err = -EINVAL; |
---|
| 7843 | + goto err_unpin_programs; |
---|
| 7844 | + } else if (len >= PATH_MAX) { |
---|
| 7845 | + err = -ENAMETOOLONG; |
---|
| 7846 | + goto err_unpin_programs; |
---|
| 7847 | + } |
---|
| 7848 | + |
---|
| 7849 | + err = bpf_program__pin(prog, buf); |
---|
| 7850 | + if (err) |
---|
| 7851 | + goto err_unpin_programs; |
---|
| 7852 | + } |
---|
| 7853 | + |
---|
| 7854 | + return 0; |
---|
| 7855 | + |
---|
| 7856 | +err_unpin_programs: |
---|
| 7857 | + while ((prog = bpf_program__prev(prog, obj))) { |
---|
| 7858 | + char buf[PATH_MAX]; |
---|
| 7859 | + int len; |
---|
| 7860 | + |
---|
| 7861 | + len = snprintf(buf, PATH_MAX, "%s/%s", path, |
---|
| 7862 | + prog->pin_name); |
---|
| 7863 | + if (len < 0) |
---|
| 7864 | + continue; |
---|
| 7865 | + else if (len >= PATH_MAX) |
---|
| 7866 | + continue; |
---|
| 7867 | + |
---|
| 7868 | + bpf_program__unpin(prog, buf); |
---|
| 7869 | + } |
---|
| 7870 | + |
---|
| 7871 | + return err; |
---|
| 7872 | +} |
---|
| 7873 | + |
---|
| 7874 | +int bpf_object__unpin_programs(struct bpf_object *obj, const char *path) |
---|
| 7875 | +{ |
---|
| 7876 | + struct bpf_program *prog; |
---|
| 7877 | + int err; |
---|
| 7878 | + |
---|
| 7879 | + if (!obj) |
---|
| 7880 | + return -ENOENT; |
---|
| 7881 | + |
---|
| 7882 | + bpf_object__for_each_program(prog, obj) { |
---|
| 7883 | + char buf[PATH_MAX]; |
---|
| 7884 | + int len; |
---|
| 7885 | + |
---|
| 7886 | + len = snprintf(buf, PATH_MAX, "%s/%s", path, |
---|
| 7887 | + prog->pin_name); |
---|
| 7888 | + if (len < 0) |
---|
| 7889 | + return -EINVAL; |
---|
| 7890 | + else if (len >= PATH_MAX) |
---|
| 7891 | + return -ENAMETOOLONG; |
---|
| 7892 | + |
---|
| 7893 | + err = bpf_program__unpin(prog, buf); |
---|
| 7894 | + if (err) |
---|
| 7895 | + return err; |
---|
| 7896 | + } |
---|
| 7897 | + |
---|
| 7898 | + return 0; |
---|
| 7899 | +} |
---|
| 7900 | + |
---|
| 7901 | +int bpf_object__pin(struct bpf_object *obj, const char *path) |
---|
| 7902 | +{ |
---|
| 7903 | + int err; |
---|
| 7904 | + |
---|
| 7905 | + err = bpf_object__pin_maps(obj, path); |
---|
| 7906 | + if (err) |
---|
| 7907 | + return err; |
---|
| 7908 | + |
---|
| 7909 | + err = bpf_object__pin_programs(obj, path); |
---|
| 7910 | + if (err) { |
---|
| 7911 | + bpf_object__unpin_maps(obj, path); |
---|
| 7912 | + return err; |
---|
| 7913 | + } |
---|
| 7914 | + |
---|
| 7915 | + return 0; |
---|
| 7916 | +} |
---|
| 7917 | + |
---|
| 7918 | +static void bpf_map__destroy(struct bpf_map *map) |
---|
| 7919 | +{ |
---|
| 7920 | + if (map->clear_priv) |
---|
| 7921 | + map->clear_priv(map, map->priv); |
---|
| 7922 | + map->priv = NULL; |
---|
| 7923 | + map->clear_priv = NULL; |
---|
| 7924 | + |
---|
| 7925 | + if (map->inner_map) { |
---|
| 7926 | + bpf_map__destroy(map->inner_map); |
---|
| 7927 | + zfree(&map->inner_map); |
---|
| 7928 | + } |
---|
| 7929 | + |
---|
| 7930 | + zfree(&map->init_slots); |
---|
| 7931 | + map->init_slots_sz = 0; |
---|
| 7932 | + |
---|
| 7933 | + if (map->mmaped) { |
---|
| 7934 | + munmap(map->mmaped, bpf_map_mmap_sz(map)); |
---|
| 7935 | + map->mmaped = NULL; |
---|
| 7936 | + } |
---|
| 7937 | + |
---|
| 7938 | + if (map->st_ops) { |
---|
| 7939 | + zfree(&map->st_ops->data); |
---|
| 7940 | + zfree(&map->st_ops->progs); |
---|
| 7941 | + zfree(&map->st_ops->kern_func_off); |
---|
| 7942 | + zfree(&map->st_ops); |
---|
| 7943 | + } |
---|
| 7944 | + |
---|
| 7945 | + zfree(&map->name); |
---|
| 7946 | + zfree(&map->pin_path); |
---|
| 7947 | + |
---|
| 7948 | + if (map->fd >= 0) |
---|
| 7949 | + zclose(map->fd); |
---|
| 7950 | +} |
---|
| 7951 | + |
---|
1843 | 7952 | void bpf_object__close(struct bpf_object *obj) |
---|
1844 | 7953 | { |
---|
1845 | 7954 | size_t i; |
---|
1846 | 7955 | |
---|
1847 | | - if (!obj) |
---|
| 7956 | + if (IS_ERR_OR_NULL(obj)) |
---|
1848 | 7957 | return; |
---|
1849 | 7958 | |
---|
1850 | 7959 | if (obj->clear_priv) |
---|
.. | .. |
---|
1853 | 7962 | bpf_object__elf_finish(obj); |
---|
1854 | 7963 | bpf_object__unload(obj); |
---|
1855 | 7964 | btf__free(obj->btf); |
---|
| 7965 | + btf_ext__free(obj->btf_ext); |
---|
1856 | 7966 | |
---|
1857 | | - for (i = 0; i < obj->nr_maps; i++) { |
---|
1858 | | - zfree(&obj->maps[i].name); |
---|
1859 | | - if (obj->maps[i].clear_priv) |
---|
1860 | | - obj->maps[i].clear_priv(&obj->maps[i], |
---|
1861 | | - obj->maps[i].priv); |
---|
1862 | | - obj->maps[i].priv = NULL; |
---|
1863 | | - obj->maps[i].clear_priv = NULL; |
---|
1864 | | - } |
---|
| 7967 | + for (i = 0; i < obj->nr_maps; i++) |
---|
| 7968 | + bpf_map__destroy(&obj->maps[i]); |
---|
| 7969 | + |
---|
| 7970 | + zfree(&obj->kconfig); |
---|
| 7971 | + zfree(&obj->externs); |
---|
| 7972 | + obj->nr_extern = 0; |
---|
| 7973 | + |
---|
1865 | 7974 | zfree(&obj->maps); |
---|
1866 | 7975 | obj->nr_maps = 0; |
---|
1867 | 7976 | |
---|
.. | .. |
---|
1894 | 8003 | return next; |
---|
1895 | 8004 | } |
---|
1896 | 8005 | |
---|
1897 | | -const char *bpf_object__name(struct bpf_object *obj) |
---|
| 8006 | +const char *bpf_object__name(const struct bpf_object *obj) |
---|
1898 | 8007 | { |
---|
1899 | | - return obj ? obj->path : ERR_PTR(-EINVAL); |
---|
| 8008 | + return obj ? obj->name : ERR_PTR(-EINVAL); |
---|
1900 | 8009 | } |
---|
1901 | 8010 | |
---|
1902 | | -unsigned int bpf_object__kversion(struct bpf_object *obj) |
---|
| 8011 | +unsigned int bpf_object__kversion(const struct bpf_object *obj) |
---|
1903 | 8012 | { |
---|
1904 | 8013 | return obj ? obj->kern_version : 0; |
---|
| 8014 | +} |
---|
| 8015 | + |
---|
| 8016 | +struct btf *bpf_object__btf(const struct bpf_object *obj) |
---|
| 8017 | +{ |
---|
| 8018 | + return obj ? obj->btf : NULL; |
---|
1905 | 8019 | } |
---|
1906 | 8020 | |
---|
1907 | 8021 | int bpf_object__btf_fd(const struct bpf_object *obj) |
---|
.. | .. |
---|
1920 | 8034 | return 0; |
---|
1921 | 8035 | } |
---|
1922 | 8036 | |
---|
1923 | | -void *bpf_object__priv(struct bpf_object *obj) |
---|
| 8037 | +void *bpf_object__priv(const struct bpf_object *obj) |
---|
1924 | 8038 | { |
---|
1925 | 8039 | return obj ? obj->priv : ERR_PTR(-EINVAL); |
---|
1926 | 8040 | } |
---|
1927 | 8041 | |
---|
1928 | 8042 | static struct bpf_program * |
---|
1929 | | -__bpf_program__next(struct bpf_program *prev, struct bpf_object *obj) |
---|
| 8043 | +__bpf_program__iter(const struct bpf_program *p, const struct bpf_object *obj, |
---|
| 8044 | + bool forward) |
---|
1930 | 8045 | { |
---|
1931 | | - size_t idx; |
---|
| 8046 | + size_t nr_programs = obj->nr_programs; |
---|
| 8047 | + ssize_t idx; |
---|
1932 | 8048 | |
---|
1933 | | - if (!obj->programs) |
---|
| 8049 | + if (!nr_programs) |
---|
1934 | 8050 | return NULL; |
---|
1935 | | - /* First handler */ |
---|
1936 | | - if (prev == NULL) |
---|
1937 | | - return &obj->programs[0]; |
---|
1938 | 8051 | |
---|
1939 | | - if (prev->obj != obj) { |
---|
1940 | | - pr_warning("error: program handler doesn't match object\n"); |
---|
| 8052 | + if (!p) |
---|
| 8053 | + /* Iter from the beginning */ |
---|
| 8054 | + return forward ? &obj->programs[0] : |
---|
| 8055 | + &obj->programs[nr_programs - 1]; |
---|
| 8056 | + |
---|
| 8057 | + if (p->obj != obj) { |
---|
| 8058 | + pr_warn("error: program handler doesn't match object\n"); |
---|
1941 | 8059 | return NULL; |
---|
1942 | 8060 | } |
---|
1943 | 8061 | |
---|
1944 | | - idx = (prev - obj->programs) + 1; |
---|
1945 | | - if (idx >= obj->nr_programs) |
---|
| 8062 | + idx = (p - obj->programs) + (forward ? 1 : -1); |
---|
| 8063 | + if (idx >= obj->nr_programs || idx < 0) |
---|
1946 | 8064 | return NULL; |
---|
1947 | 8065 | return &obj->programs[idx]; |
---|
1948 | 8066 | } |
---|
1949 | 8067 | |
---|
1950 | 8068 | struct bpf_program * |
---|
1951 | | -bpf_program__next(struct bpf_program *prev, struct bpf_object *obj) |
---|
| 8069 | +bpf_program__next(struct bpf_program *prev, const struct bpf_object *obj) |
---|
1952 | 8070 | { |
---|
1953 | 8071 | struct bpf_program *prog = prev; |
---|
1954 | 8072 | |
---|
1955 | 8073 | do { |
---|
1956 | | - prog = __bpf_program__next(prog, obj); |
---|
1957 | | - } while (prog && bpf_program__is_function_storage(prog, obj)); |
---|
| 8074 | + prog = __bpf_program__iter(prog, obj, true); |
---|
| 8075 | + } while (prog && prog_is_subprog(obj, prog)); |
---|
| 8076 | + |
---|
| 8077 | + return prog; |
---|
| 8078 | +} |
---|
| 8079 | + |
---|
| 8080 | +struct bpf_program * |
---|
| 8081 | +bpf_program__prev(struct bpf_program *next, const struct bpf_object *obj) |
---|
| 8082 | +{ |
---|
| 8083 | + struct bpf_program *prog = next; |
---|
| 8084 | + |
---|
| 8085 | + do { |
---|
| 8086 | + prog = __bpf_program__iter(prog, obj, false); |
---|
| 8087 | + } while (prog && prog_is_subprog(obj, prog)); |
---|
1958 | 8088 | |
---|
1959 | 8089 | return prog; |
---|
1960 | 8090 | } |
---|
.. | .. |
---|
1970 | 8100 | return 0; |
---|
1971 | 8101 | } |
---|
1972 | 8102 | |
---|
1973 | | -void *bpf_program__priv(struct bpf_program *prog) |
---|
| 8103 | +void *bpf_program__priv(const struct bpf_program *prog) |
---|
1974 | 8104 | { |
---|
1975 | 8105 | return prog ? prog->priv : ERR_PTR(-EINVAL); |
---|
1976 | 8106 | } |
---|
.. | .. |
---|
1980 | 8110 | prog->prog_ifindex = ifindex; |
---|
1981 | 8111 | } |
---|
1982 | 8112 | |
---|
1983 | | -const char *bpf_program__title(struct bpf_program *prog, bool needs_copy) |
---|
| 8113 | +const char *bpf_program__name(const struct bpf_program *prog) |
---|
| 8114 | +{ |
---|
| 8115 | + return prog->name; |
---|
| 8116 | +} |
---|
| 8117 | + |
---|
| 8118 | +const char *bpf_program__section_name(const struct bpf_program *prog) |
---|
| 8119 | +{ |
---|
| 8120 | + return prog->sec_name; |
---|
| 8121 | +} |
---|
| 8122 | + |
---|
| 8123 | +const char *bpf_program__title(const struct bpf_program *prog, bool needs_copy) |
---|
1984 | 8124 | { |
---|
1985 | 8125 | const char *title; |
---|
1986 | 8126 | |
---|
1987 | | - title = prog->section_name; |
---|
| 8127 | + title = prog->sec_name; |
---|
1988 | 8128 | if (needs_copy) { |
---|
1989 | 8129 | title = strdup(title); |
---|
1990 | 8130 | if (!title) { |
---|
1991 | | - pr_warning("failed to strdup program title\n"); |
---|
| 8131 | + pr_warn("failed to strdup program title\n"); |
---|
1992 | 8132 | return ERR_PTR(-ENOMEM); |
---|
1993 | 8133 | } |
---|
1994 | 8134 | } |
---|
.. | .. |
---|
1996 | 8136 | return title; |
---|
1997 | 8137 | } |
---|
1998 | 8138 | |
---|
1999 | | -int bpf_program__fd(struct bpf_program *prog) |
---|
| 8139 | +bool bpf_program__autoload(const struct bpf_program *prog) |
---|
| 8140 | +{ |
---|
| 8141 | + return prog->load; |
---|
| 8142 | +} |
---|
| 8143 | + |
---|
| 8144 | +int bpf_program__set_autoload(struct bpf_program *prog, bool autoload) |
---|
| 8145 | +{ |
---|
| 8146 | + if (prog->obj->loaded) |
---|
| 8147 | + return -EINVAL; |
---|
| 8148 | + |
---|
| 8149 | + prog->load = autoload; |
---|
| 8150 | + return 0; |
---|
| 8151 | +} |
---|
| 8152 | + |
---|
| 8153 | +int bpf_program__fd(const struct bpf_program *prog) |
---|
2000 | 8154 | { |
---|
2001 | 8155 | return bpf_program__nth_fd(prog, 0); |
---|
| 8156 | +} |
---|
| 8157 | + |
---|
| 8158 | +size_t bpf_program__size(const struct bpf_program *prog) |
---|
| 8159 | +{ |
---|
| 8160 | + return prog->insns_cnt * BPF_INSN_SZ; |
---|
2002 | 8161 | } |
---|
2003 | 8162 | |
---|
2004 | 8163 | int bpf_program__set_prep(struct bpf_program *prog, int nr_instances, |
---|
.. | .. |
---|
2010 | 8169 | return -EINVAL; |
---|
2011 | 8170 | |
---|
2012 | 8171 | if (prog->instances.nr > 0 || prog->instances.fds) { |
---|
2013 | | - pr_warning("Can't set pre-processor after loading\n"); |
---|
| 8172 | + pr_warn("Can't set pre-processor after loading\n"); |
---|
2014 | 8173 | return -EINVAL; |
---|
2015 | 8174 | } |
---|
2016 | 8175 | |
---|
2017 | 8176 | instances_fds = malloc(sizeof(int) * nr_instances); |
---|
2018 | 8177 | if (!instances_fds) { |
---|
2019 | | - pr_warning("alloc memory failed for fds\n"); |
---|
| 8178 | + pr_warn("alloc memory failed for fds\n"); |
---|
2020 | 8179 | return -ENOMEM; |
---|
2021 | 8180 | } |
---|
2022 | 8181 | |
---|
.. | .. |
---|
2029 | 8188 | return 0; |
---|
2030 | 8189 | } |
---|
2031 | 8190 | |
---|
2032 | | -int bpf_program__nth_fd(struct bpf_program *prog, int n) |
---|
| 8191 | +int bpf_program__nth_fd(const struct bpf_program *prog, int n) |
---|
2033 | 8192 | { |
---|
2034 | 8193 | int fd; |
---|
2035 | 8194 | |
---|
.. | .. |
---|
2037 | 8196 | return -EINVAL; |
---|
2038 | 8197 | |
---|
2039 | 8198 | if (n >= prog->instances.nr || n < 0) { |
---|
2040 | | - pr_warning("Can't get the %dth fd from program %s: only %d instances\n", |
---|
2041 | | - n, prog->section_name, prog->instances.nr); |
---|
| 8199 | + pr_warn("Can't get the %dth fd from program %s: only %d instances\n", |
---|
| 8200 | + n, prog->name, prog->instances.nr); |
---|
2042 | 8201 | return -EINVAL; |
---|
2043 | 8202 | } |
---|
2044 | 8203 | |
---|
2045 | 8204 | fd = prog->instances.fds[n]; |
---|
2046 | 8205 | if (fd < 0) { |
---|
2047 | | - pr_warning("%dth instance of program '%s' is invalid\n", |
---|
2048 | | - n, prog->section_name); |
---|
| 8206 | + pr_warn("%dth instance of program '%s' is invalid\n", |
---|
| 8207 | + n, prog->name); |
---|
2049 | 8208 | return -ENOENT; |
---|
2050 | 8209 | } |
---|
2051 | 8210 | |
---|
2052 | 8211 | return fd; |
---|
| 8212 | +} |
---|
| 8213 | + |
---|
| 8214 | +enum bpf_prog_type bpf_program__get_type(struct bpf_program *prog) |
---|
| 8215 | +{ |
---|
| 8216 | + return prog->type; |
---|
2053 | 8217 | } |
---|
2054 | 8218 | |
---|
2055 | 8219 | void bpf_program__set_type(struct bpf_program *prog, enum bpf_prog_type type) |
---|
.. | .. |
---|
2057 | 8221 | prog->type = type; |
---|
2058 | 8222 | } |
---|
2059 | 8223 | |
---|
2060 | | -static bool bpf_program__is_type(struct bpf_program *prog, |
---|
| 8224 | +static bool bpf_program__is_type(const struct bpf_program *prog, |
---|
2061 | 8225 | enum bpf_prog_type type) |
---|
2062 | 8226 | { |
---|
2063 | 8227 | return prog ? (prog->type == type) : false; |
---|
2064 | 8228 | } |
---|
2065 | 8229 | |
---|
2066 | | -#define BPF_PROG_TYPE_FNS(NAME, TYPE) \ |
---|
2067 | | -int bpf_program__set_##NAME(struct bpf_program *prog) \ |
---|
2068 | | -{ \ |
---|
2069 | | - if (!prog) \ |
---|
2070 | | - return -EINVAL; \ |
---|
2071 | | - bpf_program__set_type(prog, TYPE); \ |
---|
2072 | | - return 0; \ |
---|
2073 | | -} \ |
---|
2074 | | - \ |
---|
2075 | | -bool bpf_program__is_##NAME(struct bpf_program *prog) \ |
---|
2076 | | -{ \ |
---|
2077 | | - return bpf_program__is_type(prog, TYPE); \ |
---|
2078 | | -} \ |
---|
| 8230 | +#define BPF_PROG_TYPE_FNS(NAME, TYPE) \ |
---|
| 8231 | +int bpf_program__set_##NAME(struct bpf_program *prog) \ |
---|
| 8232 | +{ \ |
---|
| 8233 | + if (!prog) \ |
---|
| 8234 | + return -EINVAL; \ |
---|
| 8235 | + bpf_program__set_type(prog, TYPE); \ |
---|
| 8236 | + return 0; \ |
---|
| 8237 | +} \ |
---|
| 8238 | + \ |
---|
| 8239 | +bool bpf_program__is_##NAME(const struct bpf_program *prog) \ |
---|
| 8240 | +{ \ |
---|
| 8241 | + return bpf_program__is_type(prog, TYPE); \ |
---|
| 8242 | +} \ |
---|
2079 | 8243 | |
---|
2080 | 8244 | BPF_PROG_TYPE_FNS(socket_filter, BPF_PROG_TYPE_SOCKET_FILTER); |
---|
| 8245 | +BPF_PROG_TYPE_FNS(lsm, BPF_PROG_TYPE_LSM); |
---|
2081 | 8246 | BPF_PROG_TYPE_FNS(kprobe, BPF_PROG_TYPE_KPROBE); |
---|
2082 | 8247 | BPF_PROG_TYPE_FNS(sched_cls, BPF_PROG_TYPE_SCHED_CLS); |
---|
2083 | 8248 | BPF_PROG_TYPE_FNS(sched_act, BPF_PROG_TYPE_SCHED_ACT); |
---|
.. | .. |
---|
2085 | 8250 | BPF_PROG_TYPE_FNS(raw_tracepoint, BPF_PROG_TYPE_RAW_TRACEPOINT); |
---|
2086 | 8251 | BPF_PROG_TYPE_FNS(xdp, BPF_PROG_TYPE_XDP); |
---|
2087 | 8252 | BPF_PROG_TYPE_FNS(perf_event, BPF_PROG_TYPE_PERF_EVENT); |
---|
| 8253 | +BPF_PROG_TYPE_FNS(tracing, BPF_PROG_TYPE_TRACING); |
---|
| 8254 | +BPF_PROG_TYPE_FNS(struct_ops, BPF_PROG_TYPE_STRUCT_OPS); |
---|
| 8255 | +BPF_PROG_TYPE_FNS(extension, BPF_PROG_TYPE_EXT); |
---|
| 8256 | +BPF_PROG_TYPE_FNS(sk_lookup, BPF_PROG_TYPE_SK_LOOKUP); |
---|
| 8257 | + |
---|
| 8258 | +enum bpf_attach_type |
---|
| 8259 | +bpf_program__get_expected_attach_type(struct bpf_program *prog) |
---|
| 8260 | +{ |
---|
| 8261 | + return prog->expected_attach_type; |
---|
| 8262 | +} |
---|
2088 | 8263 | |
---|
2089 | 8264 | void bpf_program__set_expected_attach_type(struct bpf_program *prog, |
---|
2090 | 8265 | enum bpf_attach_type type) |
---|
.. | .. |
---|
2092 | 8267 | prog->expected_attach_type = type; |
---|
2093 | 8268 | } |
---|
2094 | 8269 | |
---|
2095 | | -#define BPF_PROG_SEC_FULL(string, ptype, atype) \ |
---|
2096 | | - { string, sizeof(string) - 1, ptype, atype } |
---|
| 8270 | +#define BPF_PROG_SEC_IMPL(string, ptype, eatype, eatype_optional, \ |
---|
| 8271 | + attachable, attach_btf) \ |
---|
| 8272 | + { \ |
---|
| 8273 | + .sec = string, \ |
---|
| 8274 | + .len = sizeof(string) - 1, \ |
---|
| 8275 | + .prog_type = ptype, \ |
---|
| 8276 | + .expected_attach_type = eatype, \ |
---|
| 8277 | + .is_exp_attach_type_optional = eatype_optional, \ |
---|
| 8278 | + .is_attachable = attachable, \ |
---|
| 8279 | + .is_attach_btf = attach_btf, \ |
---|
| 8280 | + } |
---|
2097 | 8281 | |
---|
2098 | | -#define BPF_PROG_SEC(string, ptype) BPF_PROG_SEC_FULL(string, ptype, 0) |
---|
| 8282 | +/* Programs that can NOT be attached. */ |
---|
| 8283 | +#define BPF_PROG_SEC(string, ptype) BPF_PROG_SEC_IMPL(string, ptype, 0, 0, 0, 0) |
---|
2099 | 8284 | |
---|
2100 | | -#define BPF_S_PROG_SEC(string, ptype) \ |
---|
2101 | | - BPF_PROG_SEC_FULL(string, BPF_PROG_TYPE_CGROUP_SOCK, ptype) |
---|
| 8285 | +/* Programs that can be attached. */ |
---|
| 8286 | +#define BPF_APROG_SEC(string, ptype, atype) \ |
---|
| 8287 | + BPF_PROG_SEC_IMPL(string, ptype, atype, true, 1, 0) |
---|
2102 | 8288 | |
---|
2103 | | -#define BPF_SA_PROG_SEC(string, ptype) \ |
---|
2104 | | - BPF_PROG_SEC_FULL(string, BPF_PROG_TYPE_CGROUP_SOCK_ADDR, ptype) |
---|
| 8289 | +/* Programs that must specify expected attach type at load time. */ |
---|
| 8290 | +#define BPF_EAPROG_SEC(string, ptype, eatype) \ |
---|
| 8291 | + BPF_PROG_SEC_IMPL(string, ptype, eatype, false, 1, 0) |
---|
2105 | 8292 | |
---|
2106 | | -static const struct { |
---|
2107 | | - const char *sec; |
---|
2108 | | - size_t len; |
---|
2109 | | - enum bpf_prog_type prog_type; |
---|
2110 | | - enum bpf_attach_type expected_attach_type; |
---|
2111 | | -} section_names[] = { |
---|
2112 | | - BPF_PROG_SEC("socket", BPF_PROG_TYPE_SOCKET_FILTER), |
---|
2113 | | - BPF_PROG_SEC("kprobe/", BPF_PROG_TYPE_KPROBE), |
---|
2114 | | - BPF_PROG_SEC("kretprobe/", BPF_PROG_TYPE_KPROBE), |
---|
2115 | | - BPF_PROG_SEC("classifier", BPF_PROG_TYPE_SCHED_CLS), |
---|
2116 | | - BPF_PROG_SEC("action", BPF_PROG_TYPE_SCHED_ACT), |
---|
2117 | | - BPF_PROG_SEC("tracepoint/", BPF_PROG_TYPE_TRACEPOINT), |
---|
2118 | | - BPF_PROG_SEC("raw_tracepoint/", BPF_PROG_TYPE_RAW_TRACEPOINT), |
---|
2119 | | - BPF_PROG_SEC("xdp", BPF_PROG_TYPE_XDP), |
---|
2120 | | - BPF_PROG_SEC("perf_event", BPF_PROG_TYPE_PERF_EVENT), |
---|
2121 | | - BPF_PROG_SEC("cgroup/skb", BPF_PROG_TYPE_CGROUP_SKB), |
---|
2122 | | - BPF_PROG_SEC("cgroup/sock", BPF_PROG_TYPE_CGROUP_SOCK), |
---|
2123 | | - BPF_PROG_SEC("cgroup/dev", BPF_PROG_TYPE_CGROUP_DEVICE), |
---|
2124 | | - BPF_PROG_SEC("lwt_in", BPF_PROG_TYPE_LWT_IN), |
---|
2125 | | - BPF_PROG_SEC("lwt_out", BPF_PROG_TYPE_LWT_OUT), |
---|
2126 | | - BPF_PROG_SEC("lwt_xmit", BPF_PROG_TYPE_LWT_XMIT), |
---|
2127 | | - BPF_PROG_SEC("lwt_seg6local", BPF_PROG_TYPE_LWT_SEG6LOCAL), |
---|
2128 | | - BPF_PROG_SEC("sockops", BPF_PROG_TYPE_SOCK_OPS), |
---|
2129 | | - BPF_PROG_SEC("sk_skb", BPF_PROG_TYPE_SK_SKB), |
---|
2130 | | - BPF_PROG_SEC("sk_msg", BPF_PROG_TYPE_SK_MSG), |
---|
2131 | | - BPF_PROG_SEC("lirc_mode2", BPF_PROG_TYPE_LIRC_MODE2), |
---|
2132 | | - BPF_SA_PROG_SEC("cgroup/bind4", BPF_CGROUP_INET4_BIND), |
---|
2133 | | - BPF_SA_PROG_SEC("cgroup/bind6", BPF_CGROUP_INET6_BIND), |
---|
2134 | | - BPF_SA_PROG_SEC("cgroup/connect4", BPF_CGROUP_INET4_CONNECT), |
---|
2135 | | - BPF_SA_PROG_SEC("cgroup/connect6", BPF_CGROUP_INET6_CONNECT), |
---|
2136 | | - BPF_SA_PROG_SEC("cgroup/sendmsg4", BPF_CGROUP_UDP4_SENDMSG), |
---|
2137 | | - BPF_SA_PROG_SEC("cgroup/sendmsg6", BPF_CGROUP_UDP6_SENDMSG), |
---|
2138 | | - BPF_S_PROG_SEC("cgroup/post_bind4", BPF_CGROUP_INET4_POST_BIND), |
---|
2139 | | - BPF_S_PROG_SEC("cgroup/post_bind6", BPF_CGROUP_INET6_POST_BIND), |
---|
| 8293 | +/* Programs that use BTF to identify attach point */ |
---|
| 8294 | +#define BPF_PROG_BTF(string, ptype, eatype) \ |
---|
| 8295 | + BPF_PROG_SEC_IMPL(string, ptype, eatype, false, 0, 1) |
---|
| 8296 | + |
---|
| 8297 | +/* Programs that can be attached but attach type can't be identified by section |
---|
| 8298 | + * name. Kept for backward compatibility. |
---|
| 8299 | + */ |
---|
| 8300 | +#define BPF_APROG_COMPAT(string, ptype) BPF_PROG_SEC(string, ptype) |
---|
| 8301 | + |
---|
| 8302 | +#define SEC_DEF(sec_pfx, ptype, ...) { \ |
---|
| 8303 | + .sec = sec_pfx, \ |
---|
| 8304 | + .len = sizeof(sec_pfx) - 1, \ |
---|
| 8305 | + .prog_type = BPF_PROG_TYPE_##ptype, \ |
---|
| 8306 | + __VA_ARGS__ \ |
---|
| 8307 | +} |
---|
| 8308 | + |
---|
| 8309 | +static struct bpf_link *attach_kprobe(const struct bpf_sec_def *sec, |
---|
| 8310 | + struct bpf_program *prog); |
---|
| 8311 | +static struct bpf_link *attach_tp(const struct bpf_sec_def *sec, |
---|
| 8312 | + struct bpf_program *prog); |
---|
| 8313 | +static struct bpf_link *attach_raw_tp(const struct bpf_sec_def *sec, |
---|
| 8314 | + struct bpf_program *prog); |
---|
| 8315 | +static struct bpf_link *attach_trace(const struct bpf_sec_def *sec, |
---|
| 8316 | + struct bpf_program *prog); |
---|
| 8317 | +static struct bpf_link *attach_lsm(const struct bpf_sec_def *sec, |
---|
| 8318 | + struct bpf_program *prog); |
---|
| 8319 | +static struct bpf_link *attach_iter(const struct bpf_sec_def *sec, |
---|
| 8320 | + struct bpf_program *prog); |
---|
| 8321 | + |
---|
| 8322 | +static const struct bpf_sec_def section_defs[] = { |
---|
| 8323 | + BPF_PROG_SEC("socket", BPF_PROG_TYPE_SOCKET_FILTER), |
---|
| 8324 | + BPF_PROG_SEC("sk_reuseport", BPF_PROG_TYPE_SK_REUSEPORT), |
---|
| 8325 | + SEC_DEF("kprobe/", KPROBE, |
---|
| 8326 | + .attach_fn = attach_kprobe), |
---|
| 8327 | + BPF_PROG_SEC("uprobe/", BPF_PROG_TYPE_KPROBE), |
---|
| 8328 | + SEC_DEF("kretprobe/", KPROBE, |
---|
| 8329 | + .attach_fn = attach_kprobe), |
---|
| 8330 | + BPF_PROG_SEC("uretprobe/", BPF_PROG_TYPE_KPROBE), |
---|
| 8331 | + BPF_PROG_SEC("classifier", BPF_PROG_TYPE_SCHED_CLS), |
---|
| 8332 | + BPF_PROG_SEC("action", BPF_PROG_TYPE_SCHED_ACT), |
---|
| 8333 | + SEC_DEF("tracepoint/", TRACEPOINT, |
---|
| 8334 | + .attach_fn = attach_tp), |
---|
| 8335 | + SEC_DEF("tp/", TRACEPOINT, |
---|
| 8336 | + .attach_fn = attach_tp), |
---|
| 8337 | + SEC_DEF("raw_tracepoint/", RAW_TRACEPOINT, |
---|
| 8338 | + .attach_fn = attach_raw_tp), |
---|
| 8339 | + SEC_DEF("raw_tp/", RAW_TRACEPOINT, |
---|
| 8340 | + .attach_fn = attach_raw_tp), |
---|
| 8341 | + SEC_DEF("tp_btf/", TRACING, |
---|
| 8342 | + .expected_attach_type = BPF_TRACE_RAW_TP, |
---|
| 8343 | + .is_attach_btf = true, |
---|
| 8344 | + .attach_fn = attach_trace), |
---|
| 8345 | + SEC_DEF("fentry/", TRACING, |
---|
| 8346 | + .expected_attach_type = BPF_TRACE_FENTRY, |
---|
| 8347 | + .is_attach_btf = true, |
---|
| 8348 | + .attach_fn = attach_trace), |
---|
| 8349 | + SEC_DEF("fmod_ret/", TRACING, |
---|
| 8350 | + .expected_attach_type = BPF_MODIFY_RETURN, |
---|
| 8351 | + .is_attach_btf = true, |
---|
| 8352 | + .attach_fn = attach_trace), |
---|
| 8353 | + SEC_DEF("fexit/", TRACING, |
---|
| 8354 | + .expected_attach_type = BPF_TRACE_FEXIT, |
---|
| 8355 | + .is_attach_btf = true, |
---|
| 8356 | + .attach_fn = attach_trace), |
---|
| 8357 | + SEC_DEF("fentry.s/", TRACING, |
---|
| 8358 | + .expected_attach_type = BPF_TRACE_FENTRY, |
---|
| 8359 | + .is_attach_btf = true, |
---|
| 8360 | + .is_sleepable = true, |
---|
| 8361 | + .attach_fn = attach_trace), |
---|
| 8362 | + SEC_DEF("fmod_ret.s/", TRACING, |
---|
| 8363 | + .expected_attach_type = BPF_MODIFY_RETURN, |
---|
| 8364 | + .is_attach_btf = true, |
---|
| 8365 | + .is_sleepable = true, |
---|
| 8366 | + .attach_fn = attach_trace), |
---|
| 8367 | + SEC_DEF("fexit.s/", TRACING, |
---|
| 8368 | + .expected_attach_type = BPF_TRACE_FEXIT, |
---|
| 8369 | + .is_attach_btf = true, |
---|
| 8370 | + .is_sleepable = true, |
---|
| 8371 | + .attach_fn = attach_trace), |
---|
| 8372 | + SEC_DEF("freplace/", EXT, |
---|
| 8373 | + .is_attach_btf = true, |
---|
| 8374 | + .attach_fn = attach_trace), |
---|
| 8375 | + SEC_DEF("lsm/", LSM, |
---|
| 8376 | + .is_attach_btf = true, |
---|
| 8377 | + .expected_attach_type = BPF_LSM_MAC, |
---|
| 8378 | + .attach_fn = attach_lsm), |
---|
| 8379 | + SEC_DEF("lsm.s/", LSM, |
---|
| 8380 | + .is_attach_btf = true, |
---|
| 8381 | + .is_sleepable = true, |
---|
| 8382 | + .expected_attach_type = BPF_LSM_MAC, |
---|
| 8383 | + .attach_fn = attach_lsm), |
---|
| 8384 | + SEC_DEF("iter/", TRACING, |
---|
| 8385 | + .expected_attach_type = BPF_TRACE_ITER, |
---|
| 8386 | + .is_attach_btf = true, |
---|
| 8387 | + .attach_fn = attach_iter), |
---|
| 8388 | + BPF_EAPROG_SEC("xdp_devmap/", BPF_PROG_TYPE_XDP, |
---|
| 8389 | + BPF_XDP_DEVMAP), |
---|
| 8390 | + BPF_EAPROG_SEC("xdp_cpumap/", BPF_PROG_TYPE_XDP, |
---|
| 8391 | + BPF_XDP_CPUMAP), |
---|
| 8392 | + BPF_APROG_SEC("xdp", BPF_PROG_TYPE_XDP, |
---|
| 8393 | + BPF_XDP), |
---|
| 8394 | + BPF_PROG_SEC("perf_event", BPF_PROG_TYPE_PERF_EVENT), |
---|
| 8395 | + BPF_PROG_SEC("lwt_in", BPF_PROG_TYPE_LWT_IN), |
---|
| 8396 | + BPF_PROG_SEC("lwt_out", BPF_PROG_TYPE_LWT_OUT), |
---|
| 8397 | + BPF_PROG_SEC("lwt_xmit", BPF_PROG_TYPE_LWT_XMIT), |
---|
| 8398 | + BPF_PROG_SEC("lwt_seg6local", BPF_PROG_TYPE_LWT_SEG6LOCAL), |
---|
| 8399 | + BPF_APROG_SEC("cgroup_skb/ingress", BPF_PROG_TYPE_CGROUP_SKB, |
---|
| 8400 | + BPF_CGROUP_INET_INGRESS), |
---|
| 8401 | + BPF_APROG_SEC("cgroup_skb/egress", BPF_PROG_TYPE_CGROUP_SKB, |
---|
| 8402 | + BPF_CGROUP_INET_EGRESS), |
---|
| 8403 | + BPF_APROG_COMPAT("cgroup/skb", BPF_PROG_TYPE_CGROUP_SKB), |
---|
| 8404 | + BPF_EAPROG_SEC("cgroup/sock_create", BPF_PROG_TYPE_CGROUP_SOCK, |
---|
| 8405 | + BPF_CGROUP_INET_SOCK_CREATE), |
---|
| 8406 | + BPF_EAPROG_SEC("cgroup/sock_release", BPF_PROG_TYPE_CGROUP_SOCK, |
---|
| 8407 | + BPF_CGROUP_INET_SOCK_RELEASE), |
---|
| 8408 | + BPF_APROG_SEC("cgroup/sock", BPF_PROG_TYPE_CGROUP_SOCK, |
---|
| 8409 | + BPF_CGROUP_INET_SOCK_CREATE), |
---|
| 8410 | + BPF_EAPROG_SEC("cgroup/post_bind4", BPF_PROG_TYPE_CGROUP_SOCK, |
---|
| 8411 | + BPF_CGROUP_INET4_POST_BIND), |
---|
| 8412 | + BPF_EAPROG_SEC("cgroup/post_bind6", BPF_PROG_TYPE_CGROUP_SOCK, |
---|
| 8413 | + BPF_CGROUP_INET6_POST_BIND), |
---|
| 8414 | + BPF_APROG_SEC("cgroup/dev", BPF_PROG_TYPE_CGROUP_DEVICE, |
---|
| 8415 | + BPF_CGROUP_DEVICE), |
---|
| 8416 | + BPF_APROG_SEC("sockops", BPF_PROG_TYPE_SOCK_OPS, |
---|
| 8417 | + BPF_CGROUP_SOCK_OPS), |
---|
| 8418 | + BPF_APROG_SEC("sk_skb/stream_parser", BPF_PROG_TYPE_SK_SKB, |
---|
| 8419 | + BPF_SK_SKB_STREAM_PARSER), |
---|
| 8420 | + BPF_APROG_SEC("sk_skb/stream_verdict", BPF_PROG_TYPE_SK_SKB, |
---|
| 8421 | + BPF_SK_SKB_STREAM_VERDICT), |
---|
| 8422 | + BPF_APROG_COMPAT("sk_skb", BPF_PROG_TYPE_SK_SKB), |
---|
| 8423 | + BPF_APROG_SEC("sk_msg", BPF_PROG_TYPE_SK_MSG, |
---|
| 8424 | + BPF_SK_MSG_VERDICT), |
---|
| 8425 | + BPF_APROG_SEC("lirc_mode2", BPF_PROG_TYPE_LIRC_MODE2, |
---|
| 8426 | + BPF_LIRC_MODE2), |
---|
| 8427 | + BPF_APROG_SEC("flow_dissector", BPF_PROG_TYPE_FLOW_DISSECTOR, |
---|
| 8428 | + BPF_FLOW_DISSECTOR), |
---|
| 8429 | + BPF_EAPROG_SEC("cgroup/bind4", BPF_PROG_TYPE_CGROUP_SOCK_ADDR, |
---|
| 8430 | + BPF_CGROUP_INET4_BIND), |
---|
| 8431 | + BPF_EAPROG_SEC("cgroup/bind6", BPF_PROG_TYPE_CGROUP_SOCK_ADDR, |
---|
| 8432 | + BPF_CGROUP_INET6_BIND), |
---|
| 8433 | + BPF_EAPROG_SEC("cgroup/connect4", BPF_PROG_TYPE_CGROUP_SOCK_ADDR, |
---|
| 8434 | + BPF_CGROUP_INET4_CONNECT), |
---|
| 8435 | + BPF_EAPROG_SEC("cgroup/connect6", BPF_PROG_TYPE_CGROUP_SOCK_ADDR, |
---|
| 8436 | + BPF_CGROUP_INET6_CONNECT), |
---|
| 8437 | + BPF_EAPROG_SEC("cgroup/sendmsg4", BPF_PROG_TYPE_CGROUP_SOCK_ADDR, |
---|
| 8438 | + BPF_CGROUP_UDP4_SENDMSG), |
---|
| 8439 | + BPF_EAPROG_SEC("cgroup/sendmsg6", BPF_PROG_TYPE_CGROUP_SOCK_ADDR, |
---|
| 8440 | + BPF_CGROUP_UDP6_SENDMSG), |
---|
| 8441 | + BPF_EAPROG_SEC("cgroup/recvmsg4", BPF_PROG_TYPE_CGROUP_SOCK_ADDR, |
---|
| 8442 | + BPF_CGROUP_UDP4_RECVMSG), |
---|
| 8443 | + BPF_EAPROG_SEC("cgroup/recvmsg6", BPF_PROG_TYPE_CGROUP_SOCK_ADDR, |
---|
| 8444 | + BPF_CGROUP_UDP6_RECVMSG), |
---|
| 8445 | + BPF_EAPROG_SEC("cgroup/getpeername4", BPF_PROG_TYPE_CGROUP_SOCK_ADDR, |
---|
| 8446 | + BPF_CGROUP_INET4_GETPEERNAME), |
---|
| 8447 | + BPF_EAPROG_SEC("cgroup/getpeername6", BPF_PROG_TYPE_CGROUP_SOCK_ADDR, |
---|
| 8448 | + BPF_CGROUP_INET6_GETPEERNAME), |
---|
| 8449 | + BPF_EAPROG_SEC("cgroup/getsockname4", BPF_PROG_TYPE_CGROUP_SOCK_ADDR, |
---|
| 8450 | + BPF_CGROUP_INET4_GETSOCKNAME), |
---|
| 8451 | + BPF_EAPROG_SEC("cgroup/getsockname6", BPF_PROG_TYPE_CGROUP_SOCK_ADDR, |
---|
| 8452 | + BPF_CGROUP_INET6_GETSOCKNAME), |
---|
| 8453 | + BPF_EAPROG_SEC("cgroup/sysctl", BPF_PROG_TYPE_CGROUP_SYSCTL, |
---|
| 8454 | + BPF_CGROUP_SYSCTL), |
---|
| 8455 | + BPF_EAPROG_SEC("cgroup/getsockopt", BPF_PROG_TYPE_CGROUP_SOCKOPT, |
---|
| 8456 | + BPF_CGROUP_GETSOCKOPT), |
---|
| 8457 | + BPF_EAPROG_SEC("cgroup/setsockopt", BPF_PROG_TYPE_CGROUP_SOCKOPT, |
---|
| 8458 | + BPF_CGROUP_SETSOCKOPT), |
---|
| 8459 | + BPF_PROG_SEC("struct_ops", BPF_PROG_TYPE_STRUCT_OPS), |
---|
| 8460 | + BPF_EAPROG_SEC("sk_lookup/", BPF_PROG_TYPE_SK_LOOKUP, |
---|
| 8461 | + BPF_SK_LOOKUP), |
---|
2140 | 8462 | }; |
---|
2141 | 8463 | |
---|
| 8464 | +#undef BPF_PROG_SEC_IMPL |
---|
2142 | 8465 | #undef BPF_PROG_SEC |
---|
2143 | | -#undef BPF_PROG_SEC_FULL |
---|
2144 | | -#undef BPF_S_PROG_SEC |
---|
2145 | | -#undef BPF_SA_PROG_SEC |
---|
| 8466 | +#undef BPF_APROG_SEC |
---|
| 8467 | +#undef BPF_EAPROG_SEC |
---|
| 8468 | +#undef BPF_APROG_COMPAT |
---|
| 8469 | +#undef SEC_DEF |
---|
| 8470 | + |
---|
| 8471 | +#define MAX_TYPE_NAME_SIZE 32 |
---|
| 8472 | + |
---|
| 8473 | +static const struct bpf_sec_def *find_sec_def(const char *sec_name) |
---|
| 8474 | +{ |
---|
| 8475 | + int i, n = ARRAY_SIZE(section_defs); |
---|
| 8476 | + |
---|
| 8477 | + for (i = 0; i < n; i++) { |
---|
| 8478 | + if (strncmp(sec_name, |
---|
| 8479 | + section_defs[i].sec, section_defs[i].len)) |
---|
| 8480 | + continue; |
---|
| 8481 | + return §ion_defs[i]; |
---|
| 8482 | + } |
---|
| 8483 | + return NULL; |
---|
| 8484 | +} |
---|
| 8485 | + |
---|
| 8486 | +static char *libbpf_get_type_names(bool attach_type) |
---|
| 8487 | +{ |
---|
| 8488 | + int i, len = ARRAY_SIZE(section_defs) * MAX_TYPE_NAME_SIZE; |
---|
| 8489 | + char *buf; |
---|
| 8490 | + |
---|
| 8491 | + buf = malloc(len); |
---|
| 8492 | + if (!buf) |
---|
| 8493 | + return NULL; |
---|
| 8494 | + |
---|
| 8495 | + buf[0] = '\0'; |
---|
| 8496 | + /* Forge string buf with all available names */ |
---|
| 8497 | + for (i = 0; i < ARRAY_SIZE(section_defs); i++) { |
---|
| 8498 | + if (attach_type && !section_defs[i].is_attachable) |
---|
| 8499 | + continue; |
---|
| 8500 | + |
---|
| 8501 | + if (strlen(buf) + strlen(section_defs[i].sec) + 2 > len) { |
---|
| 8502 | + free(buf); |
---|
| 8503 | + return NULL; |
---|
| 8504 | + } |
---|
| 8505 | + strcat(buf, " "); |
---|
| 8506 | + strcat(buf, section_defs[i].sec); |
---|
| 8507 | + } |
---|
| 8508 | + |
---|
| 8509 | + return buf; |
---|
| 8510 | +} |
---|
2146 | 8511 | |
---|
2147 | 8512 | int libbpf_prog_type_by_name(const char *name, enum bpf_prog_type *prog_type, |
---|
2148 | 8513 | enum bpf_attach_type *expected_attach_type) |
---|
2149 | 8514 | { |
---|
| 8515 | + const struct bpf_sec_def *sec_def; |
---|
| 8516 | + char *type_names; |
---|
| 8517 | + |
---|
| 8518 | + if (!name) |
---|
| 8519 | + return -EINVAL; |
---|
| 8520 | + |
---|
| 8521 | + sec_def = find_sec_def(name); |
---|
| 8522 | + if (sec_def) { |
---|
| 8523 | + *prog_type = sec_def->prog_type; |
---|
| 8524 | + *expected_attach_type = sec_def->expected_attach_type; |
---|
| 8525 | + return 0; |
---|
| 8526 | + } |
---|
| 8527 | + |
---|
| 8528 | + pr_debug("failed to guess program type from ELF section '%s'\n", name); |
---|
| 8529 | + type_names = libbpf_get_type_names(false); |
---|
| 8530 | + if (type_names != NULL) { |
---|
| 8531 | + pr_debug("supported section(type) names are:%s\n", type_names); |
---|
| 8532 | + free(type_names); |
---|
| 8533 | + } |
---|
| 8534 | + |
---|
| 8535 | + return -ESRCH; |
---|
| 8536 | +} |
---|
| 8537 | + |
---|
| 8538 | +static struct bpf_map *find_struct_ops_map_by_offset(struct bpf_object *obj, |
---|
| 8539 | + size_t offset) |
---|
| 8540 | +{ |
---|
| 8541 | + struct bpf_map *map; |
---|
| 8542 | + size_t i; |
---|
| 8543 | + |
---|
| 8544 | + for (i = 0; i < obj->nr_maps; i++) { |
---|
| 8545 | + map = &obj->maps[i]; |
---|
| 8546 | + if (!bpf_map__is_struct_ops(map)) |
---|
| 8547 | + continue; |
---|
| 8548 | + if (map->sec_offset <= offset && |
---|
| 8549 | + offset - map->sec_offset < map->def.value_size) |
---|
| 8550 | + return map; |
---|
| 8551 | + } |
---|
| 8552 | + |
---|
| 8553 | + return NULL; |
---|
| 8554 | +} |
---|
| 8555 | + |
---|
| 8556 | +/* Collect the reloc from ELF and populate the st_ops->progs[] */ |
---|
| 8557 | +static int bpf_object__collect_st_ops_relos(struct bpf_object *obj, |
---|
| 8558 | + GElf_Shdr *shdr, Elf_Data *data) |
---|
| 8559 | +{ |
---|
| 8560 | + const struct btf_member *member; |
---|
| 8561 | + struct bpf_struct_ops *st_ops; |
---|
| 8562 | + struct bpf_program *prog; |
---|
| 8563 | + unsigned int shdr_idx; |
---|
| 8564 | + const struct btf *btf; |
---|
| 8565 | + struct bpf_map *map; |
---|
| 8566 | + Elf_Data *symbols; |
---|
| 8567 | + unsigned int moff, insn_idx; |
---|
| 8568 | + const char *name; |
---|
| 8569 | + __u32 member_idx; |
---|
| 8570 | + GElf_Sym sym; |
---|
| 8571 | + GElf_Rel rel; |
---|
| 8572 | + int i, nrels; |
---|
| 8573 | + |
---|
| 8574 | + symbols = obj->efile.symbols; |
---|
| 8575 | + btf = obj->btf; |
---|
| 8576 | + nrels = shdr->sh_size / shdr->sh_entsize; |
---|
| 8577 | + for (i = 0; i < nrels; i++) { |
---|
| 8578 | + if (!gelf_getrel(data, i, &rel)) { |
---|
| 8579 | + pr_warn("struct_ops reloc: failed to get %d reloc\n", i); |
---|
| 8580 | + return -LIBBPF_ERRNO__FORMAT; |
---|
| 8581 | + } |
---|
| 8582 | + |
---|
| 8583 | + if (!gelf_getsym(symbols, GELF_R_SYM(rel.r_info), &sym)) { |
---|
| 8584 | + pr_warn("struct_ops reloc: symbol %zx not found\n", |
---|
| 8585 | + (size_t)GELF_R_SYM(rel.r_info)); |
---|
| 8586 | + return -LIBBPF_ERRNO__FORMAT; |
---|
| 8587 | + } |
---|
| 8588 | + |
---|
| 8589 | + name = elf_sym_str(obj, sym.st_name) ?: "<?>"; |
---|
| 8590 | + map = find_struct_ops_map_by_offset(obj, rel.r_offset); |
---|
| 8591 | + if (!map) { |
---|
| 8592 | + pr_warn("struct_ops reloc: cannot find map at rel.r_offset %zu\n", |
---|
| 8593 | + (size_t)rel.r_offset); |
---|
| 8594 | + return -EINVAL; |
---|
| 8595 | + } |
---|
| 8596 | + |
---|
| 8597 | + moff = rel.r_offset - map->sec_offset; |
---|
| 8598 | + shdr_idx = sym.st_shndx; |
---|
| 8599 | + st_ops = map->st_ops; |
---|
| 8600 | + pr_debug("struct_ops reloc %s: for %lld value %lld shdr_idx %u rel.r_offset %zu map->sec_offset %zu name %d (\'%s\')\n", |
---|
| 8601 | + map->name, |
---|
| 8602 | + (long long)(rel.r_info >> 32), |
---|
| 8603 | + (long long)sym.st_value, |
---|
| 8604 | + shdr_idx, (size_t)rel.r_offset, |
---|
| 8605 | + map->sec_offset, sym.st_name, name); |
---|
| 8606 | + |
---|
| 8607 | + if (shdr_idx >= SHN_LORESERVE) { |
---|
| 8608 | + pr_warn("struct_ops reloc %s: rel.r_offset %zu shdr_idx %u unsupported non-static function\n", |
---|
| 8609 | + map->name, (size_t)rel.r_offset, shdr_idx); |
---|
| 8610 | + return -LIBBPF_ERRNO__RELOC; |
---|
| 8611 | + } |
---|
| 8612 | + if (sym.st_value % BPF_INSN_SZ) { |
---|
| 8613 | + pr_warn("struct_ops reloc %s: invalid target program offset %llu\n", |
---|
| 8614 | + map->name, (unsigned long long)sym.st_value); |
---|
| 8615 | + return -LIBBPF_ERRNO__FORMAT; |
---|
| 8616 | + } |
---|
| 8617 | + insn_idx = sym.st_value / BPF_INSN_SZ; |
---|
| 8618 | + |
---|
| 8619 | + member = find_member_by_offset(st_ops->type, moff * 8); |
---|
| 8620 | + if (!member) { |
---|
| 8621 | + pr_warn("struct_ops reloc %s: cannot find member at moff %u\n", |
---|
| 8622 | + map->name, moff); |
---|
| 8623 | + return -EINVAL; |
---|
| 8624 | + } |
---|
| 8625 | + member_idx = member - btf_members(st_ops->type); |
---|
| 8626 | + name = btf__name_by_offset(btf, member->name_off); |
---|
| 8627 | + |
---|
| 8628 | + if (!resolve_func_ptr(btf, member->type, NULL)) { |
---|
| 8629 | + pr_warn("struct_ops reloc %s: cannot relocate non func ptr %s\n", |
---|
| 8630 | + map->name, name); |
---|
| 8631 | + return -EINVAL; |
---|
| 8632 | + } |
---|
| 8633 | + |
---|
| 8634 | + prog = find_prog_by_sec_insn(obj, shdr_idx, insn_idx); |
---|
| 8635 | + if (!prog) { |
---|
| 8636 | + pr_warn("struct_ops reloc %s: cannot find prog at shdr_idx %u to relocate func ptr %s\n", |
---|
| 8637 | + map->name, shdr_idx, name); |
---|
| 8638 | + return -EINVAL; |
---|
| 8639 | + } |
---|
| 8640 | + |
---|
| 8641 | + if (prog->type == BPF_PROG_TYPE_UNSPEC) { |
---|
| 8642 | + const struct bpf_sec_def *sec_def; |
---|
| 8643 | + |
---|
| 8644 | + sec_def = find_sec_def(prog->sec_name); |
---|
| 8645 | + if (sec_def && |
---|
| 8646 | + sec_def->prog_type != BPF_PROG_TYPE_STRUCT_OPS) { |
---|
| 8647 | + /* for pr_warn */ |
---|
| 8648 | + prog->type = sec_def->prog_type; |
---|
| 8649 | + goto invalid_prog; |
---|
| 8650 | + } |
---|
| 8651 | + |
---|
| 8652 | + prog->type = BPF_PROG_TYPE_STRUCT_OPS; |
---|
| 8653 | + prog->attach_btf_id = st_ops->type_id; |
---|
| 8654 | + prog->expected_attach_type = member_idx; |
---|
| 8655 | + } else if (prog->type != BPF_PROG_TYPE_STRUCT_OPS || |
---|
| 8656 | + prog->attach_btf_id != st_ops->type_id || |
---|
| 8657 | + prog->expected_attach_type != member_idx) { |
---|
| 8658 | + goto invalid_prog; |
---|
| 8659 | + } |
---|
| 8660 | + st_ops->progs[member_idx] = prog; |
---|
| 8661 | + } |
---|
| 8662 | + |
---|
| 8663 | + return 0; |
---|
| 8664 | + |
---|
| 8665 | +invalid_prog: |
---|
| 8666 | + pr_warn("struct_ops reloc %s: cannot use prog %s in sec %s with type %u attach_btf_id %u expected_attach_type %u for func ptr %s\n", |
---|
| 8667 | + map->name, prog->name, prog->sec_name, prog->type, |
---|
| 8668 | + prog->attach_btf_id, prog->expected_attach_type, name); |
---|
| 8669 | + return -EINVAL; |
---|
| 8670 | +} |
---|
| 8671 | + |
---|
| 8672 | +#define BTF_TRACE_PREFIX "btf_trace_" |
---|
| 8673 | +#define BTF_LSM_PREFIX "bpf_lsm_" |
---|
| 8674 | +#define BTF_ITER_PREFIX "bpf_iter_" |
---|
| 8675 | +#define BTF_MAX_NAME_SIZE 128 |
---|
| 8676 | + |
---|
| 8677 | +static int find_btf_by_prefix_kind(const struct btf *btf, const char *prefix, |
---|
| 8678 | + const char *name, __u32 kind) |
---|
| 8679 | +{ |
---|
| 8680 | + char btf_type_name[BTF_MAX_NAME_SIZE]; |
---|
| 8681 | + int ret; |
---|
| 8682 | + |
---|
| 8683 | + ret = snprintf(btf_type_name, sizeof(btf_type_name), |
---|
| 8684 | + "%s%s", prefix, name); |
---|
| 8685 | + /* snprintf returns the number of characters written excluding the |
---|
| 8686 | + * the terminating null. So, if >= BTF_MAX_NAME_SIZE are written, it |
---|
| 8687 | + * indicates truncation. |
---|
| 8688 | + */ |
---|
| 8689 | + if (ret < 0 || ret >= sizeof(btf_type_name)) |
---|
| 8690 | + return -ENAMETOOLONG; |
---|
| 8691 | + return btf__find_by_name_kind(btf, btf_type_name, kind); |
---|
| 8692 | +} |
---|
| 8693 | + |
---|
| 8694 | +static inline int __find_vmlinux_btf_id(struct btf *btf, const char *name, |
---|
| 8695 | + enum bpf_attach_type attach_type) |
---|
| 8696 | +{ |
---|
| 8697 | + int err; |
---|
| 8698 | + |
---|
| 8699 | + if (attach_type == BPF_TRACE_RAW_TP) |
---|
| 8700 | + err = find_btf_by_prefix_kind(btf, BTF_TRACE_PREFIX, name, |
---|
| 8701 | + BTF_KIND_TYPEDEF); |
---|
| 8702 | + else if (attach_type == BPF_LSM_MAC) |
---|
| 8703 | + err = find_btf_by_prefix_kind(btf, BTF_LSM_PREFIX, name, |
---|
| 8704 | + BTF_KIND_FUNC); |
---|
| 8705 | + else if (attach_type == BPF_TRACE_ITER) |
---|
| 8706 | + err = find_btf_by_prefix_kind(btf, BTF_ITER_PREFIX, name, |
---|
| 8707 | + BTF_KIND_FUNC); |
---|
| 8708 | + else |
---|
| 8709 | + err = btf__find_by_name_kind(btf, name, BTF_KIND_FUNC); |
---|
| 8710 | + |
---|
| 8711 | + if (err <= 0) |
---|
| 8712 | + pr_warn("%s is not found in vmlinux BTF\n", name); |
---|
| 8713 | + |
---|
| 8714 | + return err; |
---|
| 8715 | +} |
---|
| 8716 | + |
---|
| 8717 | +int libbpf_find_vmlinux_btf_id(const char *name, |
---|
| 8718 | + enum bpf_attach_type attach_type) |
---|
| 8719 | +{ |
---|
| 8720 | + struct btf *btf; |
---|
| 8721 | + int err; |
---|
| 8722 | + |
---|
| 8723 | + btf = libbpf_find_kernel_btf(); |
---|
| 8724 | + if (IS_ERR(btf)) { |
---|
| 8725 | + pr_warn("vmlinux BTF is not found\n"); |
---|
| 8726 | + return -EINVAL; |
---|
| 8727 | + } |
---|
| 8728 | + |
---|
| 8729 | + err = __find_vmlinux_btf_id(btf, name, attach_type); |
---|
| 8730 | + btf__free(btf); |
---|
| 8731 | + return err; |
---|
| 8732 | +} |
---|
| 8733 | + |
---|
| 8734 | +static int libbpf_find_prog_btf_id(const char *name, __u32 attach_prog_fd) |
---|
| 8735 | +{ |
---|
| 8736 | + struct bpf_prog_info_linear *info_linear; |
---|
| 8737 | + struct bpf_prog_info *info; |
---|
| 8738 | + struct btf *btf = NULL; |
---|
| 8739 | + int err = -EINVAL; |
---|
| 8740 | + |
---|
| 8741 | + info_linear = bpf_program__get_prog_info_linear(attach_prog_fd, 0); |
---|
| 8742 | + if (IS_ERR_OR_NULL(info_linear)) { |
---|
| 8743 | + pr_warn("failed get_prog_info_linear for FD %d\n", |
---|
| 8744 | + attach_prog_fd); |
---|
| 8745 | + return -EINVAL; |
---|
| 8746 | + } |
---|
| 8747 | + info = &info_linear->info; |
---|
| 8748 | + if (!info->btf_id) { |
---|
| 8749 | + pr_warn("The target program doesn't have BTF\n"); |
---|
| 8750 | + goto out; |
---|
| 8751 | + } |
---|
| 8752 | + if (btf__get_from_id(info->btf_id, &btf)) { |
---|
| 8753 | + pr_warn("Failed to get BTF of the program\n"); |
---|
| 8754 | + goto out; |
---|
| 8755 | + } |
---|
| 8756 | + err = btf__find_by_name_kind(btf, name, BTF_KIND_FUNC); |
---|
| 8757 | + btf__free(btf); |
---|
| 8758 | + if (err <= 0) { |
---|
| 8759 | + pr_warn("%s is not found in prog's BTF\n", name); |
---|
| 8760 | + goto out; |
---|
| 8761 | + } |
---|
| 8762 | +out: |
---|
| 8763 | + free(info_linear); |
---|
| 8764 | + return err; |
---|
| 8765 | +} |
---|
| 8766 | + |
---|
| 8767 | +static int libbpf_find_attach_btf_id(struct bpf_program *prog) |
---|
| 8768 | +{ |
---|
| 8769 | + enum bpf_attach_type attach_type = prog->expected_attach_type; |
---|
| 8770 | + __u32 attach_prog_fd = prog->attach_prog_fd; |
---|
| 8771 | + const char *name = prog->sec_name; |
---|
| 8772 | + int i, err; |
---|
| 8773 | + |
---|
| 8774 | + if (!name) |
---|
| 8775 | + return -EINVAL; |
---|
| 8776 | + |
---|
| 8777 | + for (i = 0; i < ARRAY_SIZE(section_defs); i++) { |
---|
| 8778 | + if (!section_defs[i].is_attach_btf) |
---|
| 8779 | + continue; |
---|
| 8780 | + if (strncmp(name, section_defs[i].sec, section_defs[i].len)) |
---|
| 8781 | + continue; |
---|
| 8782 | + if (attach_prog_fd) |
---|
| 8783 | + err = libbpf_find_prog_btf_id(name + section_defs[i].len, |
---|
| 8784 | + attach_prog_fd); |
---|
| 8785 | + else |
---|
| 8786 | + err = __find_vmlinux_btf_id(prog->obj->btf_vmlinux, |
---|
| 8787 | + name + section_defs[i].len, |
---|
| 8788 | + attach_type); |
---|
| 8789 | + return err; |
---|
| 8790 | + } |
---|
| 8791 | + pr_warn("failed to identify btf_id based on ELF section name '%s'\n", name); |
---|
| 8792 | + return -ESRCH; |
---|
| 8793 | +} |
---|
| 8794 | + |
---|
| 8795 | +int libbpf_attach_type_by_name(const char *name, |
---|
| 8796 | + enum bpf_attach_type *attach_type) |
---|
| 8797 | +{ |
---|
| 8798 | + char *type_names; |
---|
2150 | 8799 | int i; |
---|
2151 | 8800 | |
---|
2152 | 8801 | if (!name) |
---|
2153 | 8802 | return -EINVAL; |
---|
2154 | 8803 | |
---|
2155 | | - for (i = 0; i < ARRAY_SIZE(section_names); i++) { |
---|
2156 | | - if (strncmp(name, section_names[i].sec, section_names[i].len)) |
---|
| 8804 | + for (i = 0; i < ARRAY_SIZE(section_defs); i++) { |
---|
| 8805 | + if (strncmp(name, section_defs[i].sec, section_defs[i].len)) |
---|
2157 | 8806 | continue; |
---|
2158 | | - *prog_type = section_names[i].prog_type; |
---|
2159 | | - *expected_attach_type = section_names[i].expected_attach_type; |
---|
| 8807 | + if (!section_defs[i].is_attachable) |
---|
| 8808 | + return -EINVAL; |
---|
| 8809 | + *attach_type = section_defs[i].expected_attach_type; |
---|
2160 | 8810 | return 0; |
---|
2161 | 8811 | } |
---|
| 8812 | + pr_debug("failed to guess attach type based on ELF section name '%s'\n", name); |
---|
| 8813 | + type_names = libbpf_get_type_names(true); |
---|
| 8814 | + if (type_names != NULL) { |
---|
| 8815 | + pr_debug("attachable section(type) names are:%s\n", type_names); |
---|
| 8816 | + free(type_names); |
---|
| 8817 | + } |
---|
| 8818 | + |
---|
2162 | 8819 | return -EINVAL; |
---|
2163 | 8820 | } |
---|
2164 | 8821 | |
---|
2165 | | -static int |
---|
2166 | | -bpf_program__identify_section(struct bpf_program *prog, |
---|
2167 | | - enum bpf_prog_type *prog_type, |
---|
2168 | | - enum bpf_attach_type *expected_attach_type) |
---|
2169 | | -{ |
---|
2170 | | - return libbpf_prog_type_by_name(prog->section_name, prog_type, |
---|
2171 | | - expected_attach_type); |
---|
2172 | | -} |
---|
2173 | | - |
---|
2174 | | -int bpf_map__fd(struct bpf_map *map) |
---|
| 8822 | +int bpf_map__fd(const struct bpf_map *map) |
---|
2175 | 8823 | { |
---|
2176 | 8824 | return map ? map->fd : -EINVAL; |
---|
2177 | 8825 | } |
---|
2178 | 8826 | |
---|
2179 | | -const struct bpf_map_def *bpf_map__def(struct bpf_map *map) |
---|
| 8827 | +const struct bpf_map_def *bpf_map__def(const struct bpf_map *map) |
---|
2180 | 8828 | { |
---|
2181 | 8829 | return map ? &map->def : ERR_PTR(-EINVAL); |
---|
2182 | 8830 | } |
---|
2183 | 8831 | |
---|
2184 | | -const char *bpf_map__name(struct bpf_map *map) |
---|
| 8832 | +const char *bpf_map__name(const struct bpf_map *map) |
---|
2185 | 8833 | { |
---|
2186 | 8834 | return map ? map->name : NULL; |
---|
| 8835 | +} |
---|
| 8836 | + |
---|
| 8837 | +enum bpf_map_type bpf_map__type(const struct bpf_map *map) |
---|
| 8838 | +{ |
---|
| 8839 | + return map->def.type; |
---|
| 8840 | +} |
---|
| 8841 | + |
---|
| 8842 | +int bpf_map__set_type(struct bpf_map *map, enum bpf_map_type type) |
---|
| 8843 | +{ |
---|
| 8844 | + if (map->fd >= 0) |
---|
| 8845 | + return -EBUSY; |
---|
| 8846 | + map->def.type = type; |
---|
| 8847 | + return 0; |
---|
| 8848 | +} |
---|
| 8849 | + |
---|
| 8850 | +__u32 bpf_map__map_flags(const struct bpf_map *map) |
---|
| 8851 | +{ |
---|
| 8852 | + return map->def.map_flags; |
---|
| 8853 | +} |
---|
| 8854 | + |
---|
| 8855 | +int bpf_map__set_map_flags(struct bpf_map *map, __u32 flags) |
---|
| 8856 | +{ |
---|
| 8857 | + if (map->fd >= 0) |
---|
| 8858 | + return -EBUSY; |
---|
| 8859 | + map->def.map_flags = flags; |
---|
| 8860 | + return 0; |
---|
| 8861 | +} |
---|
| 8862 | + |
---|
| 8863 | +__u32 bpf_map__numa_node(const struct bpf_map *map) |
---|
| 8864 | +{ |
---|
| 8865 | + return map->numa_node; |
---|
| 8866 | +} |
---|
| 8867 | + |
---|
| 8868 | +int bpf_map__set_numa_node(struct bpf_map *map, __u32 numa_node) |
---|
| 8869 | +{ |
---|
| 8870 | + if (map->fd >= 0) |
---|
| 8871 | + return -EBUSY; |
---|
| 8872 | + map->numa_node = numa_node; |
---|
| 8873 | + return 0; |
---|
| 8874 | +} |
---|
| 8875 | + |
---|
| 8876 | +__u32 bpf_map__key_size(const struct bpf_map *map) |
---|
| 8877 | +{ |
---|
| 8878 | + return map->def.key_size; |
---|
| 8879 | +} |
---|
| 8880 | + |
---|
| 8881 | +int bpf_map__set_key_size(struct bpf_map *map, __u32 size) |
---|
| 8882 | +{ |
---|
| 8883 | + if (map->fd >= 0) |
---|
| 8884 | + return -EBUSY; |
---|
| 8885 | + map->def.key_size = size; |
---|
| 8886 | + return 0; |
---|
| 8887 | +} |
---|
| 8888 | + |
---|
| 8889 | +__u32 bpf_map__value_size(const struct bpf_map *map) |
---|
| 8890 | +{ |
---|
| 8891 | + return map->def.value_size; |
---|
| 8892 | +} |
---|
| 8893 | + |
---|
| 8894 | +int bpf_map__set_value_size(struct bpf_map *map, __u32 size) |
---|
| 8895 | +{ |
---|
| 8896 | + if (map->fd >= 0) |
---|
| 8897 | + return -EBUSY; |
---|
| 8898 | + map->def.value_size = size; |
---|
| 8899 | + return 0; |
---|
2187 | 8900 | } |
---|
2188 | 8901 | |
---|
2189 | 8902 | __u32 bpf_map__btf_key_type_id(const struct bpf_map *map) |
---|
.. | .. |
---|
2212 | 8925 | return 0; |
---|
2213 | 8926 | } |
---|
2214 | 8927 | |
---|
2215 | | -void *bpf_map__priv(struct bpf_map *map) |
---|
| 8928 | +void *bpf_map__priv(const struct bpf_map *map) |
---|
2216 | 8929 | { |
---|
2217 | 8930 | return map ? map->priv : ERR_PTR(-EINVAL); |
---|
2218 | 8931 | } |
---|
2219 | 8932 | |
---|
2220 | | -bool bpf_map__is_offload_neutral(struct bpf_map *map) |
---|
| 8933 | +int bpf_map__set_initial_value(struct bpf_map *map, |
---|
| 8934 | + const void *data, size_t size) |
---|
| 8935 | +{ |
---|
| 8936 | + if (!map->mmaped || map->libbpf_type == LIBBPF_MAP_KCONFIG || |
---|
| 8937 | + size != map->def.value_size || map->fd >= 0) |
---|
| 8938 | + return -EINVAL; |
---|
| 8939 | + |
---|
| 8940 | + memcpy(map->mmaped, data, size); |
---|
| 8941 | + return 0; |
---|
| 8942 | +} |
---|
| 8943 | + |
---|
| 8944 | +bool bpf_map__is_offload_neutral(const struct bpf_map *map) |
---|
2221 | 8945 | { |
---|
2222 | 8946 | return map->def.type == BPF_MAP_TYPE_PERF_EVENT_ARRAY; |
---|
2223 | 8947 | } |
---|
2224 | 8948 | |
---|
2225 | | -void bpf_map__set_ifindex(struct bpf_map *map, __u32 ifindex) |
---|
| 8949 | +bool bpf_map__is_internal(const struct bpf_map *map) |
---|
2226 | 8950 | { |
---|
2227 | | - map->map_ifindex = ifindex; |
---|
| 8951 | + return map->libbpf_type != LIBBPF_MAP_UNSPEC; |
---|
2228 | 8952 | } |
---|
2229 | 8953 | |
---|
2230 | | -struct bpf_map * |
---|
2231 | | -bpf_map__next(struct bpf_map *prev, struct bpf_object *obj) |
---|
| 8954 | +__u32 bpf_map__ifindex(const struct bpf_map *map) |
---|
2232 | 8955 | { |
---|
2233 | | - size_t idx; |
---|
| 8956 | + return map->map_ifindex; |
---|
| 8957 | +} |
---|
| 8958 | + |
---|
| 8959 | +int bpf_map__set_ifindex(struct bpf_map *map, __u32 ifindex) |
---|
| 8960 | +{ |
---|
| 8961 | + if (map->fd >= 0) |
---|
| 8962 | + return -EBUSY; |
---|
| 8963 | + map->map_ifindex = ifindex; |
---|
| 8964 | + return 0; |
---|
| 8965 | +} |
---|
| 8966 | + |
---|
| 8967 | +int bpf_map__set_inner_map_fd(struct bpf_map *map, int fd) |
---|
| 8968 | +{ |
---|
| 8969 | + if (!bpf_map_type__is_map_in_map(map->def.type)) { |
---|
| 8970 | + pr_warn("error: unsupported map type\n"); |
---|
| 8971 | + return -EINVAL; |
---|
| 8972 | + } |
---|
| 8973 | + if (map->inner_map_fd != -1) { |
---|
| 8974 | + pr_warn("error: inner_map_fd already specified\n"); |
---|
| 8975 | + return -EINVAL; |
---|
| 8976 | + } |
---|
| 8977 | + map->inner_map_fd = fd; |
---|
| 8978 | + return 0; |
---|
| 8979 | +} |
---|
| 8980 | + |
---|
| 8981 | +static struct bpf_map * |
---|
| 8982 | +__bpf_map__iter(const struct bpf_map *m, const struct bpf_object *obj, int i) |
---|
| 8983 | +{ |
---|
| 8984 | + ssize_t idx; |
---|
2234 | 8985 | struct bpf_map *s, *e; |
---|
2235 | 8986 | |
---|
2236 | 8987 | if (!obj || !obj->maps) |
---|
.. | .. |
---|
2239 | 8990 | s = obj->maps; |
---|
2240 | 8991 | e = obj->maps + obj->nr_maps; |
---|
2241 | 8992 | |
---|
2242 | | - if (prev == NULL) |
---|
2243 | | - return s; |
---|
2244 | | - |
---|
2245 | | - if ((prev < s) || (prev >= e)) { |
---|
2246 | | - pr_warning("error in %s: map handler doesn't belong to object\n", |
---|
2247 | | - __func__); |
---|
| 8993 | + if ((m < s) || (m >= e)) { |
---|
| 8994 | + pr_warn("error in %s: map handler doesn't belong to object\n", |
---|
| 8995 | + __func__); |
---|
2248 | 8996 | return NULL; |
---|
2249 | 8997 | } |
---|
2250 | 8998 | |
---|
2251 | | - idx = (prev - obj->maps) + 1; |
---|
2252 | | - if (idx >= obj->nr_maps) |
---|
| 8999 | + idx = (m - obj->maps) + i; |
---|
| 9000 | + if (idx >= obj->nr_maps || idx < 0) |
---|
2253 | 9001 | return NULL; |
---|
2254 | 9002 | return &obj->maps[idx]; |
---|
2255 | 9003 | } |
---|
2256 | 9004 | |
---|
2257 | 9005 | struct bpf_map * |
---|
2258 | | -bpf_object__find_map_by_name(struct bpf_object *obj, const char *name) |
---|
| 9006 | +bpf_map__next(const struct bpf_map *prev, const struct bpf_object *obj) |
---|
| 9007 | +{ |
---|
| 9008 | + if (prev == NULL) |
---|
| 9009 | + return obj->maps; |
---|
| 9010 | + |
---|
| 9011 | + return __bpf_map__iter(prev, obj, 1); |
---|
| 9012 | +} |
---|
| 9013 | + |
---|
| 9014 | +struct bpf_map * |
---|
| 9015 | +bpf_map__prev(const struct bpf_map *next, const struct bpf_object *obj) |
---|
| 9016 | +{ |
---|
| 9017 | + if (next == NULL) { |
---|
| 9018 | + if (!obj->nr_maps) |
---|
| 9019 | + return NULL; |
---|
| 9020 | + return obj->maps + obj->nr_maps - 1; |
---|
| 9021 | + } |
---|
| 9022 | + |
---|
| 9023 | + return __bpf_map__iter(next, obj, -1); |
---|
| 9024 | +} |
---|
| 9025 | + |
---|
| 9026 | +struct bpf_map * |
---|
| 9027 | +bpf_object__find_map_by_name(const struct bpf_object *obj, const char *name) |
---|
2259 | 9028 | { |
---|
2260 | 9029 | struct bpf_map *pos; |
---|
2261 | 9030 | |
---|
2262 | | - bpf_map__for_each(pos, obj) { |
---|
| 9031 | + bpf_object__for_each_map(pos, obj) { |
---|
2263 | 9032 | if (pos->name && !strcmp(pos->name, name)) |
---|
2264 | 9033 | return pos; |
---|
2265 | 9034 | } |
---|
2266 | 9035 | return NULL; |
---|
2267 | 9036 | } |
---|
2268 | 9037 | |
---|
| 9038 | +int |
---|
| 9039 | +bpf_object__find_map_fd_by_name(const struct bpf_object *obj, const char *name) |
---|
| 9040 | +{ |
---|
| 9041 | + return bpf_map__fd(bpf_object__find_map_by_name(obj, name)); |
---|
| 9042 | +} |
---|
| 9043 | + |
---|
2269 | 9044 | struct bpf_map * |
---|
2270 | 9045 | bpf_object__find_map_by_offset(struct bpf_object *obj, size_t offset) |
---|
2271 | 9046 | { |
---|
2272 | | - int i; |
---|
2273 | | - |
---|
2274 | | - for (i = 0; i < obj->nr_maps; i++) { |
---|
2275 | | - if (obj->maps[i].offset == offset) |
---|
2276 | | - return &obj->maps[i]; |
---|
2277 | | - } |
---|
2278 | | - return ERR_PTR(-ENOENT); |
---|
| 9047 | + return ERR_PTR(-ENOTSUP); |
---|
2279 | 9048 | } |
---|
2280 | 9049 | |
---|
2281 | 9050 | long libbpf_get_error(const void *ptr) |
---|
2282 | 9051 | { |
---|
2283 | | - if (IS_ERR(ptr)) |
---|
2284 | | - return PTR_ERR(ptr); |
---|
2285 | | - return 0; |
---|
| 9052 | + return PTR_ERR_OR_ZERO(ptr); |
---|
2286 | 9053 | } |
---|
2287 | 9054 | |
---|
2288 | 9055 | int bpf_prog_load(const char *file, enum bpf_prog_type type, |
---|
.. | .. |
---|
2303 | 9070 | { |
---|
2304 | 9071 | struct bpf_object_open_attr open_attr = {}; |
---|
2305 | 9072 | struct bpf_program *prog, *first_prog = NULL; |
---|
2306 | | - enum bpf_attach_type expected_attach_type; |
---|
2307 | | - enum bpf_prog_type prog_type; |
---|
2308 | 9073 | struct bpf_object *obj; |
---|
2309 | 9074 | struct bpf_map *map; |
---|
2310 | 9075 | int err; |
---|
.. | .. |
---|
2322 | 9087 | return -ENOENT; |
---|
2323 | 9088 | |
---|
2324 | 9089 | bpf_object__for_each_program(prog, obj) { |
---|
| 9090 | + enum bpf_attach_type attach_type = attr->expected_attach_type; |
---|
2325 | 9091 | /* |
---|
2326 | | - * If type is not specified, try to guess it based on |
---|
2327 | | - * section name. |
---|
| 9092 | + * to preserve backwards compatibility, bpf_prog_load treats |
---|
| 9093 | + * attr->prog_type, if specified, as an override to whatever |
---|
| 9094 | + * bpf_object__open guessed |
---|
2328 | 9095 | */ |
---|
2329 | | - prog_type = attr->prog_type; |
---|
2330 | | - prog->prog_ifindex = attr->ifindex; |
---|
2331 | | - expected_attach_type = attr->expected_attach_type; |
---|
2332 | | - if (prog_type == BPF_PROG_TYPE_UNSPEC) { |
---|
2333 | | - err = bpf_program__identify_section(prog, &prog_type, |
---|
2334 | | - &expected_attach_type); |
---|
2335 | | - if (err < 0) { |
---|
2336 | | - pr_warning("failed to guess program type based on section name %s\n", |
---|
2337 | | - prog->section_name); |
---|
2338 | | - bpf_object__close(obj); |
---|
2339 | | - return -EINVAL; |
---|
2340 | | - } |
---|
| 9096 | + if (attr->prog_type != BPF_PROG_TYPE_UNSPEC) { |
---|
| 9097 | + bpf_program__set_type(prog, attr->prog_type); |
---|
| 9098 | + bpf_program__set_expected_attach_type(prog, |
---|
| 9099 | + attach_type); |
---|
| 9100 | + } |
---|
| 9101 | + if (bpf_program__get_type(prog) == BPF_PROG_TYPE_UNSPEC) { |
---|
| 9102 | + /* |
---|
| 9103 | + * we haven't guessed from section name and user |
---|
| 9104 | + * didn't provide a fallback type, too bad... |
---|
| 9105 | + */ |
---|
| 9106 | + bpf_object__close(obj); |
---|
| 9107 | + return -EINVAL; |
---|
2341 | 9108 | } |
---|
2342 | 9109 | |
---|
2343 | | - bpf_program__set_type(prog, prog_type); |
---|
2344 | | - bpf_program__set_expected_attach_type(prog, |
---|
2345 | | - expected_attach_type); |
---|
2346 | | - |
---|
2347 | | - if (!bpf_program__is_function_storage(prog, obj) && !first_prog) |
---|
| 9110 | + prog->prog_ifindex = attr->ifindex; |
---|
| 9111 | + prog->log_level = attr->log_level; |
---|
| 9112 | + prog->prog_flags |= attr->prog_flags; |
---|
| 9113 | + if (!first_prog) |
---|
2348 | 9114 | first_prog = prog; |
---|
2349 | 9115 | } |
---|
2350 | 9116 | |
---|
2351 | | - bpf_map__for_each(map, obj) { |
---|
| 9117 | + bpf_object__for_each_map(map, obj) { |
---|
2352 | 9118 | if (!bpf_map__is_offload_neutral(map)) |
---|
2353 | 9119 | map->map_ifindex = attr->ifindex; |
---|
2354 | 9120 | } |
---|
2355 | 9121 | |
---|
2356 | 9122 | if (!first_prog) { |
---|
2357 | | - pr_warning("object file doesn't contain bpf program\n"); |
---|
| 9123 | + pr_warn("object file doesn't contain bpf program\n"); |
---|
2358 | 9124 | bpf_object__close(obj); |
---|
2359 | 9125 | return -ENOENT; |
---|
2360 | 9126 | } |
---|
.. | .. |
---|
2362 | 9128 | err = bpf_object__load(obj); |
---|
2363 | 9129 | if (err) { |
---|
2364 | 9130 | bpf_object__close(obj); |
---|
2365 | | - return -EINVAL; |
---|
| 9131 | + return err; |
---|
2366 | 9132 | } |
---|
2367 | 9133 | |
---|
2368 | 9134 | *pobj = obj; |
---|
.. | .. |
---|
2370 | 9136 | return 0; |
---|
2371 | 9137 | } |
---|
2372 | 9138 | |
---|
2373 | | -enum bpf_perf_event_ret |
---|
2374 | | -bpf_perf_event_read_simple(void *mem, unsigned long size, |
---|
2375 | | - unsigned long page_size, void **buf, size_t *buf_len, |
---|
2376 | | - bpf_perf_event_print_t fn, void *priv) |
---|
| 9139 | +struct bpf_link { |
---|
| 9140 | + int (*detach)(struct bpf_link *link); |
---|
| 9141 | + int (*destroy)(struct bpf_link *link); |
---|
| 9142 | + char *pin_path; /* NULL, if not pinned */ |
---|
| 9143 | + int fd; /* hook FD, -1 if not applicable */ |
---|
| 9144 | + bool disconnected; |
---|
| 9145 | +}; |
---|
| 9146 | + |
---|
| 9147 | +/* Replace link's underlying BPF program with the new one */ |
---|
| 9148 | +int bpf_link__update_program(struct bpf_link *link, struct bpf_program *prog) |
---|
2377 | 9149 | { |
---|
2378 | | - volatile struct perf_event_mmap_page *header = mem; |
---|
| 9150 | + return bpf_link_update(bpf_link__fd(link), bpf_program__fd(prog), NULL); |
---|
| 9151 | +} |
---|
| 9152 | + |
---|
| 9153 | +/* Release "ownership" of underlying BPF resource (typically, BPF program |
---|
| 9154 | + * attached to some BPF hook, e.g., tracepoint, kprobe, etc). Disconnected |
---|
| 9155 | + * link, when destructed through bpf_link__destroy() call won't attempt to |
---|
| 9156 | + * detach/unregisted that BPF resource. This is useful in situations where, |
---|
| 9157 | + * say, attached BPF program has to outlive userspace program that attached it |
---|
| 9158 | + * in the system. Depending on type of BPF program, though, there might be |
---|
| 9159 | + * additional steps (like pinning BPF program in BPF FS) necessary to ensure |
---|
| 9160 | + * exit of userspace program doesn't trigger automatic detachment and clean up |
---|
| 9161 | + * inside the kernel. |
---|
| 9162 | + */ |
---|
| 9163 | +void bpf_link__disconnect(struct bpf_link *link) |
---|
| 9164 | +{ |
---|
| 9165 | + link->disconnected = true; |
---|
| 9166 | +} |
---|
| 9167 | + |
---|
| 9168 | +int bpf_link__destroy(struct bpf_link *link) |
---|
| 9169 | +{ |
---|
| 9170 | + int err = 0; |
---|
| 9171 | + |
---|
| 9172 | + if (IS_ERR_OR_NULL(link)) |
---|
| 9173 | + return 0; |
---|
| 9174 | + |
---|
| 9175 | + if (!link->disconnected && link->detach) |
---|
| 9176 | + err = link->detach(link); |
---|
| 9177 | + if (link->destroy) |
---|
| 9178 | + link->destroy(link); |
---|
| 9179 | + if (link->pin_path) |
---|
| 9180 | + free(link->pin_path); |
---|
| 9181 | + free(link); |
---|
| 9182 | + |
---|
| 9183 | + return err; |
---|
| 9184 | +} |
---|
| 9185 | + |
---|
| 9186 | +int bpf_link__fd(const struct bpf_link *link) |
---|
| 9187 | +{ |
---|
| 9188 | + return link->fd; |
---|
| 9189 | +} |
---|
| 9190 | + |
---|
| 9191 | +const char *bpf_link__pin_path(const struct bpf_link *link) |
---|
| 9192 | +{ |
---|
| 9193 | + return link->pin_path; |
---|
| 9194 | +} |
---|
| 9195 | + |
---|
| 9196 | +static int bpf_link__detach_fd(struct bpf_link *link) |
---|
| 9197 | +{ |
---|
| 9198 | + return close(link->fd); |
---|
| 9199 | +} |
---|
| 9200 | + |
---|
| 9201 | +struct bpf_link *bpf_link__open(const char *path) |
---|
| 9202 | +{ |
---|
| 9203 | + struct bpf_link *link; |
---|
| 9204 | + int fd; |
---|
| 9205 | + |
---|
| 9206 | + fd = bpf_obj_get(path); |
---|
| 9207 | + if (fd < 0) { |
---|
| 9208 | + fd = -errno; |
---|
| 9209 | + pr_warn("failed to open link at %s: %d\n", path, fd); |
---|
| 9210 | + return ERR_PTR(fd); |
---|
| 9211 | + } |
---|
| 9212 | + |
---|
| 9213 | + link = calloc(1, sizeof(*link)); |
---|
| 9214 | + if (!link) { |
---|
| 9215 | + close(fd); |
---|
| 9216 | + return ERR_PTR(-ENOMEM); |
---|
| 9217 | + } |
---|
| 9218 | + link->detach = &bpf_link__detach_fd; |
---|
| 9219 | + link->fd = fd; |
---|
| 9220 | + |
---|
| 9221 | + link->pin_path = strdup(path); |
---|
| 9222 | + if (!link->pin_path) { |
---|
| 9223 | + bpf_link__destroy(link); |
---|
| 9224 | + return ERR_PTR(-ENOMEM); |
---|
| 9225 | + } |
---|
| 9226 | + |
---|
| 9227 | + return link; |
---|
| 9228 | +} |
---|
| 9229 | + |
---|
| 9230 | +int bpf_link__detach(struct bpf_link *link) |
---|
| 9231 | +{ |
---|
| 9232 | + return bpf_link_detach(link->fd) ? -errno : 0; |
---|
| 9233 | +} |
---|
| 9234 | + |
---|
| 9235 | +int bpf_link__pin(struct bpf_link *link, const char *path) |
---|
| 9236 | +{ |
---|
| 9237 | + int err; |
---|
| 9238 | + |
---|
| 9239 | + if (link->pin_path) |
---|
| 9240 | + return -EBUSY; |
---|
| 9241 | + err = make_parent_dir(path); |
---|
| 9242 | + if (err) |
---|
| 9243 | + return err; |
---|
| 9244 | + err = check_path(path); |
---|
| 9245 | + if (err) |
---|
| 9246 | + return err; |
---|
| 9247 | + |
---|
| 9248 | + link->pin_path = strdup(path); |
---|
| 9249 | + if (!link->pin_path) |
---|
| 9250 | + return -ENOMEM; |
---|
| 9251 | + |
---|
| 9252 | + if (bpf_obj_pin(link->fd, link->pin_path)) { |
---|
| 9253 | + err = -errno; |
---|
| 9254 | + zfree(&link->pin_path); |
---|
| 9255 | + return err; |
---|
| 9256 | + } |
---|
| 9257 | + |
---|
| 9258 | + pr_debug("link fd=%d: pinned at %s\n", link->fd, link->pin_path); |
---|
| 9259 | + return 0; |
---|
| 9260 | +} |
---|
| 9261 | + |
---|
| 9262 | +int bpf_link__unpin(struct bpf_link *link) |
---|
| 9263 | +{ |
---|
| 9264 | + int err; |
---|
| 9265 | + |
---|
| 9266 | + if (!link->pin_path) |
---|
| 9267 | + return -EINVAL; |
---|
| 9268 | + |
---|
| 9269 | + err = unlink(link->pin_path); |
---|
| 9270 | + if (err != 0) |
---|
| 9271 | + return -errno; |
---|
| 9272 | + |
---|
| 9273 | + pr_debug("link fd=%d: unpinned from %s\n", link->fd, link->pin_path); |
---|
| 9274 | + zfree(&link->pin_path); |
---|
| 9275 | + return 0; |
---|
| 9276 | +} |
---|
| 9277 | + |
---|
| 9278 | +static int bpf_link__detach_perf_event(struct bpf_link *link) |
---|
| 9279 | +{ |
---|
| 9280 | + int err; |
---|
| 9281 | + |
---|
| 9282 | + err = ioctl(link->fd, PERF_EVENT_IOC_DISABLE, 0); |
---|
| 9283 | + if (err) |
---|
| 9284 | + err = -errno; |
---|
| 9285 | + |
---|
| 9286 | + close(link->fd); |
---|
| 9287 | + return err; |
---|
| 9288 | +} |
---|
| 9289 | + |
---|
| 9290 | +struct bpf_link *bpf_program__attach_perf_event(struct bpf_program *prog, |
---|
| 9291 | + int pfd) |
---|
| 9292 | +{ |
---|
| 9293 | + char errmsg[STRERR_BUFSIZE]; |
---|
| 9294 | + struct bpf_link *link; |
---|
| 9295 | + int prog_fd, err; |
---|
| 9296 | + |
---|
| 9297 | + if (pfd < 0) { |
---|
| 9298 | + pr_warn("prog '%s': invalid perf event FD %d\n", |
---|
| 9299 | + prog->name, pfd); |
---|
| 9300 | + return ERR_PTR(-EINVAL); |
---|
| 9301 | + } |
---|
| 9302 | + prog_fd = bpf_program__fd(prog); |
---|
| 9303 | + if (prog_fd < 0) { |
---|
| 9304 | + pr_warn("prog '%s': can't attach BPF program w/o FD (did you load it?)\n", |
---|
| 9305 | + prog->name); |
---|
| 9306 | + return ERR_PTR(-EINVAL); |
---|
| 9307 | + } |
---|
| 9308 | + |
---|
| 9309 | + link = calloc(1, sizeof(*link)); |
---|
| 9310 | + if (!link) |
---|
| 9311 | + return ERR_PTR(-ENOMEM); |
---|
| 9312 | + link->detach = &bpf_link__detach_perf_event; |
---|
| 9313 | + link->fd = pfd; |
---|
| 9314 | + |
---|
| 9315 | + if (ioctl(pfd, PERF_EVENT_IOC_SET_BPF, prog_fd) < 0) { |
---|
| 9316 | + err = -errno; |
---|
| 9317 | + free(link); |
---|
| 9318 | + pr_warn("prog '%s': failed to attach to pfd %d: %s\n", |
---|
| 9319 | + prog->name, pfd, libbpf_strerror_r(err, errmsg, sizeof(errmsg))); |
---|
| 9320 | + if (err == -EPROTO) |
---|
| 9321 | + pr_warn("prog '%s': try add PERF_SAMPLE_CALLCHAIN to or remove exclude_callchain_[kernel|user] from pfd %d\n", |
---|
| 9322 | + prog->name, pfd); |
---|
| 9323 | + return ERR_PTR(err); |
---|
| 9324 | + } |
---|
| 9325 | + if (ioctl(pfd, PERF_EVENT_IOC_ENABLE, 0) < 0) { |
---|
| 9326 | + err = -errno; |
---|
| 9327 | + free(link); |
---|
| 9328 | + pr_warn("prog '%s': failed to enable pfd %d: %s\n", |
---|
| 9329 | + prog->name, pfd, libbpf_strerror_r(err, errmsg, sizeof(errmsg))); |
---|
| 9330 | + return ERR_PTR(err); |
---|
| 9331 | + } |
---|
| 9332 | + return link; |
---|
| 9333 | +} |
---|
| 9334 | + |
---|
| 9335 | +/* |
---|
| 9336 | + * this function is expected to parse integer in the range of [0, 2^31-1] from |
---|
| 9337 | + * given file using scanf format string fmt. If actual parsed value is |
---|
| 9338 | + * negative, the result might be indistinguishable from error |
---|
| 9339 | + */ |
---|
| 9340 | +static int parse_uint_from_file(const char *file, const char *fmt) |
---|
| 9341 | +{ |
---|
| 9342 | + char buf[STRERR_BUFSIZE]; |
---|
| 9343 | + int err, ret; |
---|
| 9344 | + FILE *f; |
---|
| 9345 | + |
---|
| 9346 | + f = fopen(file, "r"); |
---|
| 9347 | + if (!f) { |
---|
| 9348 | + err = -errno; |
---|
| 9349 | + pr_debug("failed to open '%s': %s\n", file, |
---|
| 9350 | + libbpf_strerror_r(err, buf, sizeof(buf))); |
---|
| 9351 | + return err; |
---|
| 9352 | + } |
---|
| 9353 | + err = fscanf(f, fmt, &ret); |
---|
| 9354 | + if (err != 1) { |
---|
| 9355 | + err = err == EOF ? -EIO : -errno; |
---|
| 9356 | + pr_debug("failed to parse '%s': %s\n", file, |
---|
| 9357 | + libbpf_strerror_r(err, buf, sizeof(buf))); |
---|
| 9358 | + fclose(f); |
---|
| 9359 | + return err; |
---|
| 9360 | + } |
---|
| 9361 | + fclose(f); |
---|
| 9362 | + return ret; |
---|
| 9363 | +} |
---|
| 9364 | + |
---|
| 9365 | +static int determine_kprobe_perf_type(void) |
---|
| 9366 | +{ |
---|
| 9367 | + const char *file = "/sys/bus/event_source/devices/kprobe/type"; |
---|
| 9368 | + |
---|
| 9369 | + return parse_uint_from_file(file, "%d\n"); |
---|
| 9370 | +} |
---|
| 9371 | + |
---|
| 9372 | +static int determine_uprobe_perf_type(void) |
---|
| 9373 | +{ |
---|
| 9374 | + const char *file = "/sys/bus/event_source/devices/uprobe/type"; |
---|
| 9375 | + |
---|
| 9376 | + return parse_uint_from_file(file, "%d\n"); |
---|
| 9377 | +} |
---|
| 9378 | + |
---|
| 9379 | +static int determine_kprobe_retprobe_bit(void) |
---|
| 9380 | +{ |
---|
| 9381 | + const char *file = "/sys/bus/event_source/devices/kprobe/format/retprobe"; |
---|
| 9382 | + |
---|
| 9383 | + return parse_uint_from_file(file, "config:%d\n"); |
---|
| 9384 | +} |
---|
| 9385 | + |
---|
| 9386 | +static int determine_uprobe_retprobe_bit(void) |
---|
| 9387 | +{ |
---|
| 9388 | + const char *file = "/sys/bus/event_source/devices/uprobe/format/retprobe"; |
---|
| 9389 | + |
---|
| 9390 | + return parse_uint_from_file(file, "config:%d\n"); |
---|
| 9391 | +} |
---|
| 9392 | + |
---|
| 9393 | +static int perf_event_open_probe(bool uprobe, bool retprobe, const char *name, |
---|
| 9394 | + uint64_t offset, int pid) |
---|
| 9395 | +{ |
---|
| 9396 | + struct perf_event_attr attr = {}; |
---|
| 9397 | + char errmsg[STRERR_BUFSIZE]; |
---|
| 9398 | + int type, pfd, err; |
---|
| 9399 | + |
---|
| 9400 | + type = uprobe ? determine_uprobe_perf_type() |
---|
| 9401 | + : determine_kprobe_perf_type(); |
---|
| 9402 | + if (type < 0) { |
---|
| 9403 | + pr_warn("failed to determine %s perf type: %s\n", |
---|
| 9404 | + uprobe ? "uprobe" : "kprobe", |
---|
| 9405 | + libbpf_strerror_r(type, errmsg, sizeof(errmsg))); |
---|
| 9406 | + return type; |
---|
| 9407 | + } |
---|
| 9408 | + if (retprobe) { |
---|
| 9409 | + int bit = uprobe ? determine_uprobe_retprobe_bit() |
---|
| 9410 | + : determine_kprobe_retprobe_bit(); |
---|
| 9411 | + |
---|
| 9412 | + if (bit < 0) { |
---|
| 9413 | + pr_warn("failed to determine %s retprobe bit: %s\n", |
---|
| 9414 | + uprobe ? "uprobe" : "kprobe", |
---|
| 9415 | + libbpf_strerror_r(bit, errmsg, sizeof(errmsg))); |
---|
| 9416 | + return bit; |
---|
| 9417 | + } |
---|
| 9418 | + attr.config |= 1 << bit; |
---|
| 9419 | + } |
---|
| 9420 | + attr.size = sizeof(attr); |
---|
| 9421 | + attr.type = type; |
---|
| 9422 | + attr.config1 = ptr_to_u64(name); /* kprobe_func or uprobe_path */ |
---|
| 9423 | + attr.config2 = offset; /* kprobe_addr or probe_offset */ |
---|
| 9424 | + |
---|
| 9425 | + /* pid filter is meaningful only for uprobes */ |
---|
| 9426 | + pfd = syscall(__NR_perf_event_open, &attr, |
---|
| 9427 | + pid < 0 ? -1 : pid /* pid */, |
---|
| 9428 | + pid == -1 ? 0 : -1 /* cpu */, |
---|
| 9429 | + -1 /* group_fd */, PERF_FLAG_FD_CLOEXEC); |
---|
| 9430 | + if (pfd < 0) { |
---|
| 9431 | + err = -errno; |
---|
| 9432 | + pr_warn("%s perf_event_open() failed: %s\n", |
---|
| 9433 | + uprobe ? "uprobe" : "kprobe", |
---|
| 9434 | + libbpf_strerror_r(err, errmsg, sizeof(errmsg))); |
---|
| 9435 | + return err; |
---|
| 9436 | + } |
---|
| 9437 | + return pfd; |
---|
| 9438 | +} |
---|
| 9439 | + |
---|
| 9440 | +struct bpf_link *bpf_program__attach_kprobe(struct bpf_program *prog, |
---|
| 9441 | + bool retprobe, |
---|
| 9442 | + const char *func_name) |
---|
| 9443 | +{ |
---|
| 9444 | + char errmsg[STRERR_BUFSIZE]; |
---|
| 9445 | + struct bpf_link *link; |
---|
| 9446 | + int pfd, err; |
---|
| 9447 | + |
---|
| 9448 | + pfd = perf_event_open_probe(false /* uprobe */, retprobe, func_name, |
---|
| 9449 | + 0 /* offset */, -1 /* pid */); |
---|
| 9450 | + if (pfd < 0) { |
---|
| 9451 | + pr_warn("prog '%s': failed to create %s '%s' perf event: %s\n", |
---|
| 9452 | + prog->name, retprobe ? "kretprobe" : "kprobe", func_name, |
---|
| 9453 | + libbpf_strerror_r(pfd, errmsg, sizeof(errmsg))); |
---|
| 9454 | + return ERR_PTR(pfd); |
---|
| 9455 | + } |
---|
| 9456 | + link = bpf_program__attach_perf_event(prog, pfd); |
---|
| 9457 | + if (IS_ERR(link)) { |
---|
| 9458 | + close(pfd); |
---|
| 9459 | + err = PTR_ERR(link); |
---|
| 9460 | + pr_warn("prog '%s': failed to attach to %s '%s': %s\n", |
---|
| 9461 | + prog->name, retprobe ? "kretprobe" : "kprobe", func_name, |
---|
| 9462 | + libbpf_strerror_r(err, errmsg, sizeof(errmsg))); |
---|
| 9463 | + return link; |
---|
| 9464 | + } |
---|
| 9465 | + return link; |
---|
| 9466 | +} |
---|
| 9467 | + |
---|
| 9468 | +static struct bpf_link *attach_kprobe(const struct bpf_sec_def *sec, |
---|
| 9469 | + struct bpf_program *prog) |
---|
| 9470 | +{ |
---|
| 9471 | + const char *func_name; |
---|
| 9472 | + bool retprobe; |
---|
| 9473 | + |
---|
| 9474 | + func_name = prog->sec_name + sec->len; |
---|
| 9475 | + retprobe = strcmp(sec->sec, "kretprobe/") == 0; |
---|
| 9476 | + |
---|
| 9477 | + return bpf_program__attach_kprobe(prog, retprobe, func_name); |
---|
| 9478 | +} |
---|
| 9479 | + |
---|
| 9480 | +struct bpf_link *bpf_program__attach_uprobe(struct bpf_program *prog, |
---|
| 9481 | + bool retprobe, pid_t pid, |
---|
| 9482 | + const char *binary_path, |
---|
| 9483 | + size_t func_offset) |
---|
| 9484 | +{ |
---|
| 9485 | + char errmsg[STRERR_BUFSIZE]; |
---|
| 9486 | + struct bpf_link *link; |
---|
| 9487 | + int pfd, err; |
---|
| 9488 | + |
---|
| 9489 | + pfd = perf_event_open_probe(true /* uprobe */, retprobe, |
---|
| 9490 | + binary_path, func_offset, pid); |
---|
| 9491 | + if (pfd < 0) { |
---|
| 9492 | + pr_warn("prog '%s': failed to create %s '%s:0x%zx' perf event: %s\n", |
---|
| 9493 | + prog->name, retprobe ? "uretprobe" : "uprobe", |
---|
| 9494 | + binary_path, func_offset, |
---|
| 9495 | + libbpf_strerror_r(pfd, errmsg, sizeof(errmsg))); |
---|
| 9496 | + return ERR_PTR(pfd); |
---|
| 9497 | + } |
---|
| 9498 | + link = bpf_program__attach_perf_event(prog, pfd); |
---|
| 9499 | + if (IS_ERR(link)) { |
---|
| 9500 | + close(pfd); |
---|
| 9501 | + err = PTR_ERR(link); |
---|
| 9502 | + pr_warn("prog '%s': failed to attach to %s '%s:0x%zx': %s\n", |
---|
| 9503 | + prog->name, retprobe ? "uretprobe" : "uprobe", |
---|
| 9504 | + binary_path, func_offset, |
---|
| 9505 | + libbpf_strerror_r(err, errmsg, sizeof(errmsg))); |
---|
| 9506 | + return link; |
---|
| 9507 | + } |
---|
| 9508 | + return link; |
---|
| 9509 | +} |
---|
| 9510 | + |
---|
| 9511 | +static int determine_tracepoint_id(const char *tp_category, |
---|
| 9512 | + const char *tp_name) |
---|
| 9513 | +{ |
---|
| 9514 | + char file[PATH_MAX]; |
---|
| 9515 | + int ret; |
---|
| 9516 | + |
---|
| 9517 | + ret = snprintf(file, sizeof(file), |
---|
| 9518 | + "/sys/kernel/debug/tracing/events/%s/%s/id", |
---|
| 9519 | + tp_category, tp_name); |
---|
| 9520 | + if (ret < 0) |
---|
| 9521 | + return -errno; |
---|
| 9522 | + if (ret >= sizeof(file)) { |
---|
| 9523 | + pr_debug("tracepoint %s/%s path is too long\n", |
---|
| 9524 | + tp_category, tp_name); |
---|
| 9525 | + return -E2BIG; |
---|
| 9526 | + } |
---|
| 9527 | + return parse_uint_from_file(file, "%d\n"); |
---|
| 9528 | +} |
---|
| 9529 | + |
---|
| 9530 | +static int perf_event_open_tracepoint(const char *tp_category, |
---|
| 9531 | + const char *tp_name) |
---|
| 9532 | +{ |
---|
| 9533 | + struct perf_event_attr attr = {}; |
---|
| 9534 | + char errmsg[STRERR_BUFSIZE]; |
---|
| 9535 | + int tp_id, pfd, err; |
---|
| 9536 | + |
---|
| 9537 | + tp_id = determine_tracepoint_id(tp_category, tp_name); |
---|
| 9538 | + if (tp_id < 0) { |
---|
| 9539 | + pr_warn("failed to determine tracepoint '%s/%s' perf event ID: %s\n", |
---|
| 9540 | + tp_category, tp_name, |
---|
| 9541 | + libbpf_strerror_r(tp_id, errmsg, sizeof(errmsg))); |
---|
| 9542 | + return tp_id; |
---|
| 9543 | + } |
---|
| 9544 | + |
---|
| 9545 | + attr.type = PERF_TYPE_TRACEPOINT; |
---|
| 9546 | + attr.size = sizeof(attr); |
---|
| 9547 | + attr.config = tp_id; |
---|
| 9548 | + |
---|
| 9549 | + pfd = syscall(__NR_perf_event_open, &attr, -1 /* pid */, 0 /* cpu */, |
---|
| 9550 | + -1 /* group_fd */, PERF_FLAG_FD_CLOEXEC); |
---|
| 9551 | + if (pfd < 0) { |
---|
| 9552 | + err = -errno; |
---|
| 9553 | + pr_warn("tracepoint '%s/%s' perf_event_open() failed: %s\n", |
---|
| 9554 | + tp_category, tp_name, |
---|
| 9555 | + libbpf_strerror_r(err, errmsg, sizeof(errmsg))); |
---|
| 9556 | + return err; |
---|
| 9557 | + } |
---|
| 9558 | + return pfd; |
---|
| 9559 | +} |
---|
| 9560 | + |
---|
| 9561 | +struct bpf_link *bpf_program__attach_tracepoint(struct bpf_program *prog, |
---|
| 9562 | + const char *tp_category, |
---|
| 9563 | + const char *tp_name) |
---|
| 9564 | +{ |
---|
| 9565 | + char errmsg[STRERR_BUFSIZE]; |
---|
| 9566 | + struct bpf_link *link; |
---|
| 9567 | + int pfd, err; |
---|
| 9568 | + |
---|
| 9569 | + pfd = perf_event_open_tracepoint(tp_category, tp_name); |
---|
| 9570 | + if (pfd < 0) { |
---|
| 9571 | + pr_warn("prog '%s': failed to create tracepoint '%s/%s' perf event: %s\n", |
---|
| 9572 | + prog->name, tp_category, tp_name, |
---|
| 9573 | + libbpf_strerror_r(pfd, errmsg, sizeof(errmsg))); |
---|
| 9574 | + return ERR_PTR(pfd); |
---|
| 9575 | + } |
---|
| 9576 | + link = bpf_program__attach_perf_event(prog, pfd); |
---|
| 9577 | + if (IS_ERR(link)) { |
---|
| 9578 | + close(pfd); |
---|
| 9579 | + err = PTR_ERR(link); |
---|
| 9580 | + pr_warn("prog '%s': failed to attach to tracepoint '%s/%s': %s\n", |
---|
| 9581 | + prog->name, tp_category, tp_name, |
---|
| 9582 | + libbpf_strerror_r(err, errmsg, sizeof(errmsg))); |
---|
| 9583 | + return link; |
---|
| 9584 | + } |
---|
| 9585 | + return link; |
---|
| 9586 | +} |
---|
| 9587 | + |
---|
| 9588 | +static struct bpf_link *attach_tp(const struct bpf_sec_def *sec, |
---|
| 9589 | + struct bpf_program *prog) |
---|
| 9590 | +{ |
---|
| 9591 | + char *sec_name, *tp_cat, *tp_name; |
---|
| 9592 | + struct bpf_link *link; |
---|
| 9593 | + |
---|
| 9594 | + sec_name = strdup(prog->sec_name); |
---|
| 9595 | + if (!sec_name) |
---|
| 9596 | + return ERR_PTR(-ENOMEM); |
---|
| 9597 | + |
---|
| 9598 | + /* extract "tp/<category>/<name>" */ |
---|
| 9599 | + tp_cat = sec_name + sec->len; |
---|
| 9600 | + tp_name = strchr(tp_cat, '/'); |
---|
| 9601 | + if (!tp_name) { |
---|
| 9602 | + link = ERR_PTR(-EINVAL); |
---|
| 9603 | + goto out; |
---|
| 9604 | + } |
---|
| 9605 | + *tp_name = '\0'; |
---|
| 9606 | + tp_name++; |
---|
| 9607 | + |
---|
| 9608 | + link = bpf_program__attach_tracepoint(prog, tp_cat, tp_name); |
---|
| 9609 | +out: |
---|
| 9610 | + free(sec_name); |
---|
| 9611 | + return link; |
---|
| 9612 | +} |
---|
| 9613 | + |
---|
| 9614 | +struct bpf_link *bpf_program__attach_raw_tracepoint(struct bpf_program *prog, |
---|
| 9615 | + const char *tp_name) |
---|
| 9616 | +{ |
---|
| 9617 | + char errmsg[STRERR_BUFSIZE]; |
---|
| 9618 | + struct bpf_link *link; |
---|
| 9619 | + int prog_fd, pfd; |
---|
| 9620 | + |
---|
| 9621 | + prog_fd = bpf_program__fd(prog); |
---|
| 9622 | + if (prog_fd < 0) { |
---|
| 9623 | + pr_warn("prog '%s': can't attach before loaded\n", prog->name); |
---|
| 9624 | + return ERR_PTR(-EINVAL); |
---|
| 9625 | + } |
---|
| 9626 | + |
---|
| 9627 | + link = calloc(1, sizeof(*link)); |
---|
| 9628 | + if (!link) |
---|
| 9629 | + return ERR_PTR(-ENOMEM); |
---|
| 9630 | + link->detach = &bpf_link__detach_fd; |
---|
| 9631 | + |
---|
| 9632 | + pfd = bpf_raw_tracepoint_open(tp_name, prog_fd); |
---|
| 9633 | + if (pfd < 0) { |
---|
| 9634 | + pfd = -errno; |
---|
| 9635 | + free(link); |
---|
| 9636 | + pr_warn("prog '%s': failed to attach to raw tracepoint '%s': %s\n", |
---|
| 9637 | + prog->name, tp_name, libbpf_strerror_r(pfd, errmsg, sizeof(errmsg))); |
---|
| 9638 | + return ERR_PTR(pfd); |
---|
| 9639 | + } |
---|
| 9640 | + link->fd = pfd; |
---|
| 9641 | + return link; |
---|
| 9642 | +} |
---|
| 9643 | + |
---|
| 9644 | +static struct bpf_link *attach_raw_tp(const struct bpf_sec_def *sec, |
---|
| 9645 | + struct bpf_program *prog) |
---|
| 9646 | +{ |
---|
| 9647 | + const char *tp_name = prog->sec_name + sec->len; |
---|
| 9648 | + |
---|
| 9649 | + return bpf_program__attach_raw_tracepoint(prog, tp_name); |
---|
| 9650 | +} |
---|
| 9651 | + |
---|
| 9652 | +/* Common logic for all BPF program types that attach to a btf_id */ |
---|
| 9653 | +static struct bpf_link *bpf_program__attach_btf_id(struct bpf_program *prog) |
---|
| 9654 | +{ |
---|
| 9655 | + char errmsg[STRERR_BUFSIZE]; |
---|
| 9656 | + struct bpf_link *link; |
---|
| 9657 | + int prog_fd, pfd; |
---|
| 9658 | + |
---|
| 9659 | + prog_fd = bpf_program__fd(prog); |
---|
| 9660 | + if (prog_fd < 0) { |
---|
| 9661 | + pr_warn("prog '%s': can't attach before loaded\n", prog->name); |
---|
| 9662 | + return ERR_PTR(-EINVAL); |
---|
| 9663 | + } |
---|
| 9664 | + |
---|
| 9665 | + link = calloc(1, sizeof(*link)); |
---|
| 9666 | + if (!link) |
---|
| 9667 | + return ERR_PTR(-ENOMEM); |
---|
| 9668 | + link->detach = &bpf_link__detach_fd; |
---|
| 9669 | + |
---|
| 9670 | + pfd = bpf_raw_tracepoint_open(NULL, prog_fd); |
---|
| 9671 | + if (pfd < 0) { |
---|
| 9672 | + pfd = -errno; |
---|
| 9673 | + free(link); |
---|
| 9674 | + pr_warn("prog '%s': failed to attach: %s\n", |
---|
| 9675 | + prog->name, libbpf_strerror_r(pfd, errmsg, sizeof(errmsg))); |
---|
| 9676 | + return ERR_PTR(pfd); |
---|
| 9677 | + } |
---|
| 9678 | + link->fd = pfd; |
---|
| 9679 | + return (struct bpf_link *)link; |
---|
| 9680 | +} |
---|
| 9681 | + |
---|
| 9682 | +struct bpf_link *bpf_program__attach_trace(struct bpf_program *prog) |
---|
| 9683 | +{ |
---|
| 9684 | + return bpf_program__attach_btf_id(prog); |
---|
| 9685 | +} |
---|
| 9686 | + |
---|
| 9687 | +struct bpf_link *bpf_program__attach_lsm(struct bpf_program *prog) |
---|
| 9688 | +{ |
---|
| 9689 | + return bpf_program__attach_btf_id(prog); |
---|
| 9690 | +} |
---|
| 9691 | + |
---|
| 9692 | +static struct bpf_link *attach_trace(const struct bpf_sec_def *sec, |
---|
| 9693 | + struct bpf_program *prog) |
---|
| 9694 | +{ |
---|
| 9695 | + return bpf_program__attach_trace(prog); |
---|
| 9696 | +} |
---|
| 9697 | + |
---|
| 9698 | +static struct bpf_link *attach_lsm(const struct bpf_sec_def *sec, |
---|
| 9699 | + struct bpf_program *prog) |
---|
| 9700 | +{ |
---|
| 9701 | + return bpf_program__attach_lsm(prog); |
---|
| 9702 | +} |
---|
| 9703 | + |
---|
| 9704 | +static struct bpf_link *attach_iter(const struct bpf_sec_def *sec, |
---|
| 9705 | + struct bpf_program *prog) |
---|
| 9706 | +{ |
---|
| 9707 | + return bpf_program__attach_iter(prog, NULL); |
---|
| 9708 | +} |
---|
| 9709 | + |
---|
| 9710 | +static struct bpf_link * |
---|
| 9711 | +bpf_program__attach_fd(struct bpf_program *prog, int target_fd, int btf_id, |
---|
| 9712 | + const char *target_name) |
---|
| 9713 | +{ |
---|
| 9714 | + DECLARE_LIBBPF_OPTS(bpf_link_create_opts, opts, |
---|
| 9715 | + .target_btf_id = btf_id); |
---|
| 9716 | + enum bpf_attach_type attach_type; |
---|
| 9717 | + char errmsg[STRERR_BUFSIZE]; |
---|
| 9718 | + struct bpf_link *link; |
---|
| 9719 | + int prog_fd, link_fd; |
---|
| 9720 | + |
---|
| 9721 | + prog_fd = bpf_program__fd(prog); |
---|
| 9722 | + if (prog_fd < 0) { |
---|
| 9723 | + pr_warn("prog '%s': can't attach before loaded\n", prog->name); |
---|
| 9724 | + return ERR_PTR(-EINVAL); |
---|
| 9725 | + } |
---|
| 9726 | + |
---|
| 9727 | + link = calloc(1, sizeof(*link)); |
---|
| 9728 | + if (!link) |
---|
| 9729 | + return ERR_PTR(-ENOMEM); |
---|
| 9730 | + link->detach = &bpf_link__detach_fd; |
---|
| 9731 | + |
---|
| 9732 | + attach_type = bpf_program__get_expected_attach_type(prog); |
---|
| 9733 | + link_fd = bpf_link_create(prog_fd, target_fd, attach_type, &opts); |
---|
| 9734 | + if (link_fd < 0) { |
---|
| 9735 | + link_fd = -errno; |
---|
| 9736 | + free(link); |
---|
| 9737 | + pr_warn("prog '%s': failed to attach to %s: %s\n", |
---|
| 9738 | + prog->name, target_name, |
---|
| 9739 | + libbpf_strerror_r(link_fd, errmsg, sizeof(errmsg))); |
---|
| 9740 | + return ERR_PTR(link_fd); |
---|
| 9741 | + } |
---|
| 9742 | + link->fd = link_fd; |
---|
| 9743 | + return link; |
---|
| 9744 | +} |
---|
| 9745 | + |
---|
| 9746 | +struct bpf_link * |
---|
| 9747 | +bpf_program__attach_cgroup(struct bpf_program *prog, int cgroup_fd) |
---|
| 9748 | +{ |
---|
| 9749 | + return bpf_program__attach_fd(prog, cgroup_fd, 0, "cgroup"); |
---|
| 9750 | +} |
---|
| 9751 | + |
---|
| 9752 | +struct bpf_link * |
---|
| 9753 | +bpf_program__attach_netns(struct bpf_program *prog, int netns_fd) |
---|
| 9754 | +{ |
---|
| 9755 | + return bpf_program__attach_fd(prog, netns_fd, 0, "netns"); |
---|
| 9756 | +} |
---|
| 9757 | + |
---|
| 9758 | +struct bpf_link *bpf_program__attach_xdp(struct bpf_program *prog, int ifindex) |
---|
| 9759 | +{ |
---|
| 9760 | + /* target_fd/target_ifindex use the same field in LINK_CREATE */ |
---|
| 9761 | + return bpf_program__attach_fd(prog, ifindex, 0, "xdp"); |
---|
| 9762 | +} |
---|
| 9763 | + |
---|
| 9764 | +struct bpf_link *bpf_program__attach_freplace(struct bpf_program *prog, |
---|
| 9765 | + int target_fd, |
---|
| 9766 | + const char *attach_func_name) |
---|
| 9767 | +{ |
---|
| 9768 | + int btf_id; |
---|
| 9769 | + |
---|
| 9770 | + if (!!target_fd != !!attach_func_name) { |
---|
| 9771 | + pr_warn("prog '%s': supply none or both of target_fd and attach_func_name\n", |
---|
| 9772 | + prog->name); |
---|
| 9773 | + return ERR_PTR(-EINVAL); |
---|
| 9774 | + } |
---|
| 9775 | + |
---|
| 9776 | + if (prog->type != BPF_PROG_TYPE_EXT) { |
---|
| 9777 | + pr_warn("prog '%s': only BPF_PROG_TYPE_EXT can attach as freplace", |
---|
| 9778 | + prog->name); |
---|
| 9779 | + return ERR_PTR(-EINVAL); |
---|
| 9780 | + } |
---|
| 9781 | + |
---|
| 9782 | + if (target_fd) { |
---|
| 9783 | + btf_id = libbpf_find_prog_btf_id(attach_func_name, target_fd); |
---|
| 9784 | + if (btf_id < 0) |
---|
| 9785 | + return ERR_PTR(btf_id); |
---|
| 9786 | + |
---|
| 9787 | + return bpf_program__attach_fd(prog, target_fd, btf_id, "freplace"); |
---|
| 9788 | + } else { |
---|
| 9789 | + /* no target, so use raw_tracepoint_open for compatibility |
---|
| 9790 | + * with old kernels |
---|
| 9791 | + */ |
---|
| 9792 | + return bpf_program__attach_trace(prog); |
---|
| 9793 | + } |
---|
| 9794 | +} |
---|
| 9795 | + |
---|
| 9796 | +struct bpf_link * |
---|
| 9797 | +bpf_program__attach_iter(struct bpf_program *prog, |
---|
| 9798 | + const struct bpf_iter_attach_opts *opts) |
---|
| 9799 | +{ |
---|
| 9800 | + DECLARE_LIBBPF_OPTS(bpf_link_create_opts, link_create_opts); |
---|
| 9801 | + char errmsg[STRERR_BUFSIZE]; |
---|
| 9802 | + struct bpf_link *link; |
---|
| 9803 | + int prog_fd, link_fd; |
---|
| 9804 | + __u32 target_fd = 0; |
---|
| 9805 | + |
---|
| 9806 | + if (!OPTS_VALID(opts, bpf_iter_attach_opts)) |
---|
| 9807 | + return ERR_PTR(-EINVAL); |
---|
| 9808 | + |
---|
| 9809 | + link_create_opts.iter_info = OPTS_GET(opts, link_info, (void *)0); |
---|
| 9810 | + link_create_opts.iter_info_len = OPTS_GET(opts, link_info_len, 0); |
---|
| 9811 | + |
---|
| 9812 | + prog_fd = bpf_program__fd(prog); |
---|
| 9813 | + if (prog_fd < 0) { |
---|
| 9814 | + pr_warn("prog '%s': can't attach before loaded\n", prog->name); |
---|
| 9815 | + return ERR_PTR(-EINVAL); |
---|
| 9816 | + } |
---|
| 9817 | + |
---|
| 9818 | + link = calloc(1, sizeof(*link)); |
---|
| 9819 | + if (!link) |
---|
| 9820 | + return ERR_PTR(-ENOMEM); |
---|
| 9821 | + link->detach = &bpf_link__detach_fd; |
---|
| 9822 | + |
---|
| 9823 | + link_fd = bpf_link_create(prog_fd, target_fd, BPF_TRACE_ITER, |
---|
| 9824 | + &link_create_opts); |
---|
| 9825 | + if (link_fd < 0) { |
---|
| 9826 | + link_fd = -errno; |
---|
| 9827 | + free(link); |
---|
| 9828 | + pr_warn("prog '%s': failed to attach to iterator: %s\n", |
---|
| 9829 | + prog->name, libbpf_strerror_r(link_fd, errmsg, sizeof(errmsg))); |
---|
| 9830 | + return ERR_PTR(link_fd); |
---|
| 9831 | + } |
---|
| 9832 | + link->fd = link_fd; |
---|
| 9833 | + return link; |
---|
| 9834 | +} |
---|
| 9835 | + |
---|
| 9836 | +struct bpf_link *bpf_program__attach(struct bpf_program *prog) |
---|
| 9837 | +{ |
---|
| 9838 | + const struct bpf_sec_def *sec_def; |
---|
| 9839 | + |
---|
| 9840 | + sec_def = find_sec_def(prog->sec_name); |
---|
| 9841 | + if (!sec_def || !sec_def->attach_fn) |
---|
| 9842 | + return ERR_PTR(-ESRCH); |
---|
| 9843 | + |
---|
| 9844 | + return sec_def->attach_fn(sec_def, prog); |
---|
| 9845 | +} |
---|
| 9846 | + |
---|
| 9847 | +static int bpf_link__detach_struct_ops(struct bpf_link *link) |
---|
| 9848 | +{ |
---|
| 9849 | + __u32 zero = 0; |
---|
| 9850 | + |
---|
| 9851 | + if (bpf_map_delete_elem(link->fd, &zero)) |
---|
| 9852 | + return -errno; |
---|
| 9853 | + |
---|
| 9854 | + return 0; |
---|
| 9855 | +} |
---|
| 9856 | + |
---|
| 9857 | +struct bpf_link *bpf_map__attach_struct_ops(struct bpf_map *map) |
---|
| 9858 | +{ |
---|
| 9859 | + struct bpf_struct_ops *st_ops; |
---|
| 9860 | + struct bpf_link *link; |
---|
| 9861 | + __u32 i, zero = 0; |
---|
| 9862 | + int err; |
---|
| 9863 | + |
---|
| 9864 | + if (!bpf_map__is_struct_ops(map) || map->fd == -1) |
---|
| 9865 | + return ERR_PTR(-EINVAL); |
---|
| 9866 | + |
---|
| 9867 | + link = calloc(1, sizeof(*link)); |
---|
| 9868 | + if (!link) |
---|
| 9869 | + return ERR_PTR(-EINVAL); |
---|
| 9870 | + |
---|
| 9871 | + st_ops = map->st_ops; |
---|
| 9872 | + for (i = 0; i < btf_vlen(st_ops->type); i++) { |
---|
| 9873 | + struct bpf_program *prog = st_ops->progs[i]; |
---|
| 9874 | + void *kern_data; |
---|
| 9875 | + int prog_fd; |
---|
| 9876 | + |
---|
| 9877 | + if (!prog) |
---|
| 9878 | + continue; |
---|
| 9879 | + |
---|
| 9880 | + prog_fd = bpf_program__fd(prog); |
---|
| 9881 | + kern_data = st_ops->kern_vdata + st_ops->kern_func_off[i]; |
---|
| 9882 | + *(unsigned long *)kern_data = prog_fd; |
---|
| 9883 | + } |
---|
| 9884 | + |
---|
| 9885 | + err = bpf_map_update_elem(map->fd, &zero, st_ops->kern_vdata, 0); |
---|
| 9886 | + if (err) { |
---|
| 9887 | + err = -errno; |
---|
| 9888 | + free(link); |
---|
| 9889 | + return ERR_PTR(err); |
---|
| 9890 | + } |
---|
| 9891 | + |
---|
| 9892 | + link->detach = bpf_link__detach_struct_ops; |
---|
| 9893 | + link->fd = map->fd; |
---|
| 9894 | + |
---|
| 9895 | + return link; |
---|
| 9896 | +} |
---|
| 9897 | + |
---|
| 9898 | +enum bpf_perf_event_ret |
---|
| 9899 | +bpf_perf_event_read_simple(void *mmap_mem, size_t mmap_size, size_t page_size, |
---|
| 9900 | + void **copy_mem, size_t *copy_size, |
---|
| 9901 | + bpf_perf_event_print_t fn, void *private_data) |
---|
| 9902 | +{ |
---|
| 9903 | + struct perf_event_mmap_page *header = mmap_mem; |
---|
| 9904 | + __u64 data_head = ring_buffer_read_head(header); |
---|
2379 | 9905 | __u64 data_tail = header->data_tail; |
---|
2380 | | - __u64 data_head = header->data_head; |
---|
2381 | | - int ret = LIBBPF_PERF_EVENT_ERROR; |
---|
2382 | | - void *base, *begin, *end; |
---|
| 9906 | + void *base = ((__u8 *)header) + page_size; |
---|
| 9907 | + int ret = LIBBPF_PERF_EVENT_CONT; |
---|
| 9908 | + struct perf_event_header *ehdr; |
---|
| 9909 | + size_t ehdr_size; |
---|
2383 | 9910 | |
---|
2384 | | - asm volatile("" ::: "memory"); /* in real code it should be smp_rmb() */ |
---|
2385 | | - if (data_head == data_tail) |
---|
2386 | | - return LIBBPF_PERF_EVENT_CONT; |
---|
| 9911 | + while (data_head != data_tail) { |
---|
| 9912 | + ehdr = base + (data_tail & (mmap_size - 1)); |
---|
| 9913 | + ehdr_size = ehdr->size; |
---|
2387 | 9914 | |
---|
2388 | | - base = ((char *)header) + page_size; |
---|
| 9915 | + if (((void *)ehdr) + ehdr_size > base + mmap_size) { |
---|
| 9916 | + void *copy_start = ehdr; |
---|
| 9917 | + size_t len_first = base + mmap_size - copy_start; |
---|
| 9918 | + size_t len_secnd = ehdr_size - len_first; |
---|
2389 | 9919 | |
---|
2390 | | - begin = base + data_tail % size; |
---|
2391 | | - end = base + data_head % size; |
---|
2392 | | - |
---|
2393 | | - while (begin != end) { |
---|
2394 | | - struct perf_event_header *ehdr; |
---|
2395 | | - |
---|
2396 | | - ehdr = begin; |
---|
2397 | | - if (begin + ehdr->size > base + size) { |
---|
2398 | | - long len = base + size - begin; |
---|
2399 | | - |
---|
2400 | | - if (*buf_len < ehdr->size) { |
---|
2401 | | - free(*buf); |
---|
2402 | | - *buf = malloc(ehdr->size); |
---|
2403 | | - if (!*buf) { |
---|
| 9920 | + if (*copy_size < ehdr_size) { |
---|
| 9921 | + free(*copy_mem); |
---|
| 9922 | + *copy_mem = malloc(ehdr_size); |
---|
| 9923 | + if (!*copy_mem) { |
---|
| 9924 | + *copy_size = 0; |
---|
2404 | 9925 | ret = LIBBPF_PERF_EVENT_ERROR; |
---|
2405 | 9926 | break; |
---|
2406 | 9927 | } |
---|
2407 | | - *buf_len = ehdr->size; |
---|
| 9928 | + *copy_size = ehdr_size; |
---|
2408 | 9929 | } |
---|
2409 | 9930 | |
---|
2410 | | - memcpy(*buf, begin, len); |
---|
2411 | | - memcpy(*buf + len, base, ehdr->size - len); |
---|
2412 | | - ehdr = (void *)*buf; |
---|
2413 | | - begin = base + ehdr->size - len; |
---|
2414 | | - } else if (begin + ehdr->size == base + size) { |
---|
2415 | | - begin = base; |
---|
2416 | | - } else { |
---|
2417 | | - begin += ehdr->size; |
---|
| 9931 | + memcpy(*copy_mem, copy_start, len_first); |
---|
| 9932 | + memcpy(*copy_mem + len_first, base, len_secnd); |
---|
| 9933 | + ehdr = *copy_mem; |
---|
2418 | 9934 | } |
---|
2419 | 9935 | |
---|
2420 | | - ret = fn(ehdr, priv); |
---|
| 9936 | + ret = fn(ehdr, private_data); |
---|
| 9937 | + data_tail += ehdr_size; |
---|
2421 | 9938 | if (ret != LIBBPF_PERF_EVENT_CONT) |
---|
2422 | 9939 | break; |
---|
2423 | | - |
---|
2424 | | - data_tail += ehdr->size; |
---|
2425 | 9940 | } |
---|
2426 | 9941 | |
---|
2427 | | - __sync_synchronize(); /* smp_mb() */ |
---|
2428 | | - header->data_tail = data_tail; |
---|
2429 | | - |
---|
| 9942 | + ring_buffer_write_tail(header, data_tail); |
---|
2430 | 9943 | return ret; |
---|
2431 | 9944 | } |
---|
| 9945 | + |
---|
| 9946 | +struct perf_buffer; |
---|
| 9947 | + |
---|
| 9948 | +struct perf_buffer_params { |
---|
| 9949 | + struct perf_event_attr *attr; |
---|
| 9950 | + /* if event_cb is specified, it takes precendence */ |
---|
| 9951 | + perf_buffer_event_fn event_cb; |
---|
| 9952 | + /* sample_cb and lost_cb are higher-level common-case callbacks */ |
---|
| 9953 | + perf_buffer_sample_fn sample_cb; |
---|
| 9954 | + perf_buffer_lost_fn lost_cb; |
---|
| 9955 | + void *ctx; |
---|
| 9956 | + int cpu_cnt; |
---|
| 9957 | + int *cpus; |
---|
| 9958 | + int *map_keys; |
---|
| 9959 | +}; |
---|
| 9960 | + |
---|
| 9961 | +struct perf_cpu_buf { |
---|
| 9962 | + struct perf_buffer *pb; |
---|
| 9963 | + void *base; /* mmap()'ed memory */ |
---|
| 9964 | + void *buf; /* for reconstructing segmented data */ |
---|
| 9965 | + size_t buf_size; |
---|
| 9966 | + int fd; |
---|
| 9967 | + int cpu; |
---|
| 9968 | + int map_key; |
---|
| 9969 | +}; |
---|
| 9970 | + |
---|
| 9971 | +struct perf_buffer { |
---|
| 9972 | + perf_buffer_event_fn event_cb; |
---|
| 9973 | + perf_buffer_sample_fn sample_cb; |
---|
| 9974 | + perf_buffer_lost_fn lost_cb; |
---|
| 9975 | + void *ctx; /* passed into callbacks */ |
---|
| 9976 | + |
---|
| 9977 | + size_t page_size; |
---|
| 9978 | + size_t mmap_size; |
---|
| 9979 | + struct perf_cpu_buf **cpu_bufs; |
---|
| 9980 | + struct epoll_event *events; |
---|
| 9981 | + int cpu_cnt; /* number of allocated CPU buffers */ |
---|
| 9982 | + int epoll_fd; /* perf event FD */ |
---|
| 9983 | + int map_fd; /* BPF_MAP_TYPE_PERF_EVENT_ARRAY BPF map FD */ |
---|
| 9984 | +}; |
---|
| 9985 | + |
---|
| 9986 | +static void perf_buffer__free_cpu_buf(struct perf_buffer *pb, |
---|
| 9987 | + struct perf_cpu_buf *cpu_buf) |
---|
| 9988 | +{ |
---|
| 9989 | + if (!cpu_buf) |
---|
| 9990 | + return; |
---|
| 9991 | + if (cpu_buf->base && |
---|
| 9992 | + munmap(cpu_buf->base, pb->mmap_size + pb->page_size)) |
---|
| 9993 | + pr_warn("failed to munmap cpu_buf #%d\n", cpu_buf->cpu); |
---|
| 9994 | + if (cpu_buf->fd >= 0) { |
---|
| 9995 | + ioctl(cpu_buf->fd, PERF_EVENT_IOC_DISABLE, 0); |
---|
| 9996 | + close(cpu_buf->fd); |
---|
| 9997 | + } |
---|
| 9998 | + free(cpu_buf->buf); |
---|
| 9999 | + free(cpu_buf); |
---|
| 10000 | +} |
---|
| 10001 | + |
---|
| 10002 | +void perf_buffer__free(struct perf_buffer *pb) |
---|
| 10003 | +{ |
---|
| 10004 | + int i; |
---|
| 10005 | + |
---|
| 10006 | + if (IS_ERR_OR_NULL(pb)) |
---|
| 10007 | + return; |
---|
| 10008 | + if (pb->cpu_bufs) { |
---|
| 10009 | + for (i = 0; i < pb->cpu_cnt; i++) { |
---|
| 10010 | + struct perf_cpu_buf *cpu_buf = pb->cpu_bufs[i]; |
---|
| 10011 | + |
---|
| 10012 | + if (!cpu_buf) |
---|
| 10013 | + continue; |
---|
| 10014 | + |
---|
| 10015 | + bpf_map_delete_elem(pb->map_fd, &cpu_buf->map_key); |
---|
| 10016 | + perf_buffer__free_cpu_buf(pb, cpu_buf); |
---|
| 10017 | + } |
---|
| 10018 | + free(pb->cpu_bufs); |
---|
| 10019 | + } |
---|
| 10020 | + if (pb->epoll_fd >= 0) |
---|
| 10021 | + close(pb->epoll_fd); |
---|
| 10022 | + free(pb->events); |
---|
| 10023 | + free(pb); |
---|
| 10024 | +} |
---|
| 10025 | + |
---|
| 10026 | +static struct perf_cpu_buf * |
---|
| 10027 | +perf_buffer__open_cpu_buf(struct perf_buffer *pb, struct perf_event_attr *attr, |
---|
| 10028 | + int cpu, int map_key) |
---|
| 10029 | +{ |
---|
| 10030 | + struct perf_cpu_buf *cpu_buf; |
---|
| 10031 | + char msg[STRERR_BUFSIZE]; |
---|
| 10032 | + int err; |
---|
| 10033 | + |
---|
| 10034 | + cpu_buf = calloc(1, sizeof(*cpu_buf)); |
---|
| 10035 | + if (!cpu_buf) |
---|
| 10036 | + return ERR_PTR(-ENOMEM); |
---|
| 10037 | + |
---|
| 10038 | + cpu_buf->pb = pb; |
---|
| 10039 | + cpu_buf->cpu = cpu; |
---|
| 10040 | + cpu_buf->map_key = map_key; |
---|
| 10041 | + |
---|
| 10042 | + cpu_buf->fd = syscall(__NR_perf_event_open, attr, -1 /* pid */, cpu, |
---|
| 10043 | + -1, PERF_FLAG_FD_CLOEXEC); |
---|
| 10044 | + if (cpu_buf->fd < 0) { |
---|
| 10045 | + err = -errno; |
---|
| 10046 | + pr_warn("failed to open perf buffer event on cpu #%d: %s\n", |
---|
| 10047 | + cpu, libbpf_strerror_r(err, msg, sizeof(msg))); |
---|
| 10048 | + goto error; |
---|
| 10049 | + } |
---|
| 10050 | + |
---|
| 10051 | + cpu_buf->base = mmap(NULL, pb->mmap_size + pb->page_size, |
---|
| 10052 | + PROT_READ | PROT_WRITE, MAP_SHARED, |
---|
| 10053 | + cpu_buf->fd, 0); |
---|
| 10054 | + if (cpu_buf->base == MAP_FAILED) { |
---|
| 10055 | + cpu_buf->base = NULL; |
---|
| 10056 | + err = -errno; |
---|
| 10057 | + pr_warn("failed to mmap perf buffer on cpu #%d: %s\n", |
---|
| 10058 | + cpu, libbpf_strerror_r(err, msg, sizeof(msg))); |
---|
| 10059 | + goto error; |
---|
| 10060 | + } |
---|
| 10061 | + |
---|
| 10062 | + if (ioctl(cpu_buf->fd, PERF_EVENT_IOC_ENABLE, 0) < 0) { |
---|
| 10063 | + err = -errno; |
---|
| 10064 | + pr_warn("failed to enable perf buffer event on cpu #%d: %s\n", |
---|
| 10065 | + cpu, libbpf_strerror_r(err, msg, sizeof(msg))); |
---|
| 10066 | + goto error; |
---|
| 10067 | + } |
---|
| 10068 | + |
---|
| 10069 | + return cpu_buf; |
---|
| 10070 | + |
---|
| 10071 | +error: |
---|
| 10072 | + perf_buffer__free_cpu_buf(pb, cpu_buf); |
---|
| 10073 | + return (struct perf_cpu_buf *)ERR_PTR(err); |
---|
| 10074 | +} |
---|
| 10075 | + |
---|
| 10076 | +static struct perf_buffer *__perf_buffer__new(int map_fd, size_t page_cnt, |
---|
| 10077 | + struct perf_buffer_params *p); |
---|
| 10078 | + |
---|
| 10079 | +struct perf_buffer *perf_buffer__new(int map_fd, size_t page_cnt, |
---|
| 10080 | + const struct perf_buffer_opts *opts) |
---|
| 10081 | +{ |
---|
| 10082 | + struct perf_buffer_params p = {}; |
---|
| 10083 | + struct perf_event_attr attr = { 0, }; |
---|
| 10084 | + |
---|
| 10085 | + attr.config = PERF_COUNT_SW_BPF_OUTPUT; |
---|
| 10086 | + attr.type = PERF_TYPE_SOFTWARE; |
---|
| 10087 | + attr.sample_type = PERF_SAMPLE_RAW; |
---|
| 10088 | + attr.sample_period = 1; |
---|
| 10089 | + attr.wakeup_events = 1; |
---|
| 10090 | + |
---|
| 10091 | + p.attr = &attr; |
---|
| 10092 | + p.sample_cb = opts ? opts->sample_cb : NULL; |
---|
| 10093 | + p.lost_cb = opts ? opts->lost_cb : NULL; |
---|
| 10094 | + p.ctx = opts ? opts->ctx : NULL; |
---|
| 10095 | + |
---|
| 10096 | + return __perf_buffer__new(map_fd, page_cnt, &p); |
---|
| 10097 | +} |
---|
| 10098 | + |
---|
| 10099 | +struct perf_buffer * |
---|
| 10100 | +perf_buffer__new_raw(int map_fd, size_t page_cnt, |
---|
| 10101 | + const struct perf_buffer_raw_opts *opts) |
---|
| 10102 | +{ |
---|
| 10103 | + struct perf_buffer_params p = {}; |
---|
| 10104 | + |
---|
| 10105 | + p.attr = opts->attr; |
---|
| 10106 | + p.event_cb = opts->event_cb; |
---|
| 10107 | + p.ctx = opts->ctx; |
---|
| 10108 | + p.cpu_cnt = opts->cpu_cnt; |
---|
| 10109 | + p.cpus = opts->cpus; |
---|
| 10110 | + p.map_keys = opts->map_keys; |
---|
| 10111 | + |
---|
| 10112 | + return __perf_buffer__new(map_fd, page_cnt, &p); |
---|
| 10113 | +} |
---|
| 10114 | + |
---|
| 10115 | +static struct perf_buffer *__perf_buffer__new(int map_fd, size_t page_cnt, |
---|
| 10116 | + struct perf_buffer_params *p) |
---|
| 10117 | +{ |
---|
| 10118 | + const char *online_cpus_file = "/sys/devices/system/cpu/online"; |
---|
| 10119 | + struct bpf_map_info map; |
---|
| 10120 | + char msg[STRERR_BUFSIZE]; |
---|
| 10121 | + struct perf_buffer *pb; |
---|
| 10122 | + bool *online = NULL; |
---|
| 10123 | + __u32 map_info_len; |
---|
| 10124 | + int err, i, j, n; |
---|
| 10125 | + |
---|
| 10126 | + if (page_cnt & (page_cnt - 1)) { |
---|
| 10127 | + pr_warn("page count should be power of two, but is %zu\n", |
---|
| 10128 | + page_cnt); |
---|
| 10129 | + return ERR_PTR(-EINVAL); |
---|
| 10130 | + } |
---|
| 10131 | + |
---|
| 10132 | + /* best-effort sanity checks */ |
---|
| 10133 | + memset(&map, 0, sizeof(map)); |
---|
| 10134 | + map_info_len = sizeof(map); |
---|
| 10135 | + err = bpf_obj_get_info_by_fd(map_fd, &map, &map_info_len); |
---|
| 10136 | + if (err) { |
---|
| 10137 | + err = -errno; |
---|
| 10138 | + /* if BPF_OBJ_GET_INFO_BY_FD is supported, will return |
---|
| 10139 | + * -EBADFD, -EFAULT, or -E2BIG on real error |
---|
| 10140 | + */ |
---|
| 10141 | + if (err != -EINVAL) { |
---|
| 10142 | + pr_warn("failed to get map info for map FD %d: %s\n", |
---|
| 10143 | + map_fd, libbpf_strerror_r(err, msg, sizeof(msg))); |
---|
| 10144 | + return ERR_PTR(err); |
---|
| 10145 | + } |
---|
| 10146 | + pr_debug("failed to get map info for FD %d; API not supported? Ignoring...\n", |
---|
| 10147 | + map_fd); |
---|
| 10148 | + } else { |
---|
| 10149 | + if (map.type != BPF_MAP_TYPE_PERF_EVENT_ARRAY) { |
---|
| 10150 | + pr_warn("map '%s' should be BPF_MAP_TYPE_PERF_EVENT_ARRAY\n", |
---|
| 10151 | + map.name); |
---|
| 10152 | + return ERR_PTR(-EINVAL); |
---|
| 10153 | + } |
---|
| 10154 | + } |
---|
| 10155 | + |
---|
| 10156 | + pb = calloc(1, sizeof(*pb)); |
---|
| 10157 | + if (!pb) |
---|
| 10158 | + return ERR_PTR(-ENOMEM); |
---|
| 10159 | + |
---|
| 10160 | + pb->event_cb = p->event_cb; |
---|
| 10161 | + pb->sample_cb = p->sample_cb; |
---|
| 10162 | + pb->lost_cb = p->lost_cb; |
---|
| 10163 | + pb->ctx = p->ctx; |
---|
| 10164 | + |
---|
| 10165 | + pb->page_size = getpagesize(); |
---|
| 10166 | + pb->mmap_size = pb->page_size * page_cnt; |
---|
| 10167 | + pb->map_fd = map_fd; |
---|
| 10168 | + |
---|
| 10169 | + pb->epoll_fd = epoll_create1(EPOLL_CLOEXEC); |
---|
| 10170 | + if (pb->epoll_fd < 0) { |
---|
| 10171 | + err = -errno; |
---|
| 10172 | + pr_warn("failed to create epoll instance: %s\n", |
---|
| 10173 | + libbpf_strerror_r(err, msg, sizeof(msg))); |
---|
| 10174 | + goto error; |
---|
| 10175 | + } |
---|
| 10176 | + |
---|
| 10177 | + if (p->cpu_cnt > 0) { |
---|
| 10178 | + pb->cpu_cnt = p->cpu_cnt; |
---|
| 10179 | + } else { |
---|
| 10180 | + pb->cpu_cnt = libbpf_num_possible_cpus(); |
---|
| 10181 | + if (pb->cpu_cnt < 0) { |
---|
| 10182 | + err = pb->cpu_cnt; |
---|
| 10183 | + goto error; |
---|
| 10184 | + } |
---|
| 10185 | + if (map.max_entries && map.max_entries < pb->cpu_cnt) |
---|
| 10186 | + pb->cpu_cnt = map.max_entries; |
---|
| 10187 | + } |
---|
| 10188 | + |
---|
| 10189 | + pb->events = calloc(pb->cpu_cnt, sizeof(*pb->events)); |
---|
| 10190 | + if (!pb->events) { |
---|
| 10191 | + err = -ENOMEM; |
---|
| 10192 | + pr_warn("failed to allocate events: out of memory\n"); |
---|
| 10193 | + goto error; |
---|
| 10194 | + } |
---|
| 10195 | + pb->cpu_bufs = calloc(pb->cpu_cnt, sizeof(*pb->cpu_bufs)); |
---|
| 10196 | + if (!pb->cpu_bufs) { |
---|
| 10197 | + err = -ENOMEM; |
---|
| 10198 | + pr_warn("failed to allocate buffers: out of memory\n"); |
---|
| 10199 | + goto error; |
---|
| 10200 | + } |
---|
| 10201 | + |
---|
| 10202 | + err = parse_cpu_mask_file(online_cpus_file, &online, &n); |
---|
| 10203 | + if (err) { |
---|
| 10204 | + pr_warn("failed to get online CPU mask: %d\n", err); |
---|
| 10205 | + goto error; |
---|
| 10206 | + } |
---|
| 10207 | + |
---|
| 10208 | + for (i = 0, j = 0; i < pb->cpu_cnt; i++) { |
---|
| 10209 | + struct perf_cpu_buf *cpu_buf; |
---|
| 10210 | + int cpu, map_key; |
---|
| 10211 | + |
---|
| 10212 | + cpu = p->cpu_cnt > 0 ? p->cpus[i] : i; |
---|
| 10213 | + map_key = p->cpu_cnt > 0 ? p->map_keys[i] : i; |
---|
| 10214 | + |
---|
| 10215 | + /* in case user didn't explicitly requested particular CPUs to |
---|
| 10216 | + * be attached to, skip offline/not present CPUs |
---|
| 10217 | + */ |
---|
| 10218 | + if (p->cpu_cnt <= 0 && (cpu >= n || !online[cpu])) |
---|
| 10219 | + continue; |
---|
| 10220 | + |
---|
| 10221 | + cpu_buf = perf_buffer__open_cpu_buf(pb, p->attr, cpu, map_key); |
---|
| 10222 | + if (IS_ERR(cpu_buf)) { |
---|
| 10223 | + err = PTR_ERR(cpu_buf); |
---|
| 10224 | + goto error; |
---|
| 10225 | + } |
---|
| 10226 | + |
---|
| 10227 | + pb->cpu_bufs[j] = cpu_buf; |
---|
| 10228 | + |
---|
| 10229 | + err = bpf_map_update_elem(pb->map_fd, &map_key, |
---|
| 10230 | + &cpu_buf->fd, 0); |
---|
| 10231 | + if (err) { |
---|
| 10232 | + err = -errno; |
---|
| 10233 | + pr_warn("failed to set cpu #%d, key %d -> perf FD %d: %s\n", |
---|
| 10234 | + cpu, map_key, cpu_buf->fd, |
---|
| 10235 | + libbpf_strerror_r(err, msg, sizeof(msg))); |
---|
| 10236 | + goto error; |
---|
| 10237 | + } |
---|
| 10238 | + |
---|
| 10239 | + pb->events[j].events = EPOLLIN; |
---|
| 10240 | + pb->events[j].data.ptr = cpu_buf; |
---|
| 10241 | + if (epoll_ctl(pb->epoll_fd, EPOLL_CTL_ADD, cpu_buf->fd, |
---|
| 10242 | + &pb->events[j]) < 0) { |
---|
| 10243 | + err = -errno; |
---|
| 10244 | + pr_warn("failed to epoll_ctl cpu #%d perf FD %d: %s\n", |
---|
| 10245 | + cpu, cpu_buf->fd, |
---|
| 10246 | + libbpf_strerror_r(err, msg, sizeof(msg))); |
---|
| 10247 | + goto error; |
---|
| 10248 | + } |
---|
| 10249 | + j++; |
---|
| 10250 | + } |
---|
| 10251 | + pb->cpu_cnt = j; |
---|
| 10252 | + free(online); |
---|
| 10253 | + |
---|
| 10254 | + return pb; |
---|
| 10255 | + |
---|
| 10256 | +error: |
---|
| 10257 | + free(online); |
---|
| 10258 | + if (pb) |
---|
| 10259 | + perf_buffer__free(pb); |
---|
| 10260 | + return ERR_PTR(err); |
---|
| 10261 | +} |
---|
| 10262 | + |
---|
| 10263 | +struct perf_sample_raw { |
---|
| 10264 | + struct perf_event_header header; |
---|
| 10265 | + uint32_t size; |
---|
| 10266 | + char data[]; |
---|
| 10267 | +}; |
---|
| 10268 | + |
---|
| 10269 | +struct perf_sample_lost { |
---|
| 10270 | + struct perf_event_header header; |
---|
| 10271 | + uint64_t id; |
---|
| 10272 | + uint64_t lost; |
---|
| 10273 | + uint64_t sample_id; |
---|
| 10274 | +}; |
---|
| 10275 | + |
---|
| 10276 | +static enum bpf_perf_event_ret |
---|
| 10277 | +perf_buffer__process_record(struct perf_event_header *e, void *ctx) |
---|
| 10278 | +{ |
---|
| 10279 | + struct perf_cpu_buf *cpu_buf = ctx; |
---|
| 10280 | + struct perf_buffer *pb = cpu_buf->pb; |
---|
| 10281 | + void *data = e; |
---|
| 10282 | + |
---|
| 10283 | + /* user wants full control over parsing perf event */ |
---|
| 10284 | + if (pb->event_cb) |
---|
| 10285 | + return pb->event_cb(pb->ctx, cpu_buf->cpu, e); |
---|
| 10286 | + |
---|
| 10287 | + switch (e->type) { |
---|
| 10288 | + case PERF_RECORD_SAMPLE: { |
---|
| 10289 | + struct perf_sample_raw *s = data; |
---|
| 10290 | + |
---|
| 10291 | + if (pb->sample_cb) |
---|
| 10292 | + pb->sample_cb(pb->ctx, cpu_buf->cpu, s->data, s->size); |
---|
| 10293 | + break; |
---|
| 10294 | + } |
---|
| 10295 | + case PERF_RECORD_LOST: { |
---|
| 10296 | + struct perf_sample_lost *s = data; |
---|
| 10297 | + |
---|
| 10298 | + if (pb->lost_cb) |
---|
| 10299 | + pb->lost_cb(pb->ctx, cpu_buf->cpu, s->lost); |
---|
| 10300 | + break; |
---|
| 10301 | + } |
---|
| 10302 | + default: |
---|
| 10303 | + pr_warn("unknown perf sample type %d\n", e->type); |
---|
| 10304 | + return LIBBPF_PERF_EVENT_ERROR; |
---|
| 10305 | + } |
---|
| 10306 | + return LIBBPF_PERF_EVENT_CONT; |
---|
| 10307 | +} |
---|
| 10308 | + |
---|
| 10309 | +static int perf_buffer__process_records(struct perf_buffer *pb, |
---|
| 10310 | + struct perf_cpu_buf *cpu_buf) |
---|
| 10311 | +{ |
---|
| 10312 | + enum bpf_perf_event_ret ret; |
---|
| 10313 | + |
---|
| 10314 | + ret = bpf_perf_event_read_simple(cpu_buf->base, pb->mmap_size, |
---|
| 10315 | + pb->page_size, &cpu_buf->buf, |
---|
| 10316 | + &cpu_buf->buf_size, |
---|
| 10317 | + perf_buffer__process_record, cpu_buf); |
---|
| 10318 | + if (ret != LIBBPF_PERF_EVENT_CONT) |
---|
| 10319 | + return ret; |
---|
| 10320 | + return 0; |
---|
| 10321 | +} |
---|
| 10322 | + |
---|
| 10323 | +int perf_buffer__epoll_fd(const struct perf_buffer *pb) |
---|
| 10324 | +{ |
---|
| 10325 | + return pb->epoll_fd; |
---|
| 10326 | +} |
---|
| 10327 | + |
---|
| 10328 | +int perf_buffer__poll(struct perf_buffer *pb, int timeout_ms) |
---|
| 10329 | +{ |
---|
| 10330 | + int i, cnt, err; |
---|
| 10331 | + |
---|
| 10332 | + cnt = epoll_wait(pb->epoll_fd, pb->events, pb->cpu_cnt, timeout_ms); |
---|
| 10333 | + for (i = 0; i < cnt; i++) { |
---|
| 10334 | + struct perf_cpu_buf *cpu_buf = pb->events[i].data.ptr; |
---|
| 10335 | + |
---|
| 10336 | + err = perf_buffer__process_records(pb, cpu_buf); |
---|
| 10337 | + if (err) { |
---|
| 10338 | + pr_warn("error while processing records: %d\n", err); |
---|
| 10339 | + return err; |
---|
| 10340 | + } |
---|
| 10341 | + } |
---|
| 10342 | + return cnt < 0 ? -errno : cnt; |
---|
| 10343 | +} |
---|
| 10344 | + |
---|
| 10345 | +/* Return number of PERF_EVENT_ARRAY map slots set up by this perf_buffer |
---|
| 10346 | + * manager. |
---|
| 10347 | + */ |
---|
| 10348 | +size_t perf_buffer__buffer_cnt(const struct perf_buffer *pb) |
---|
| 10349 | +{ |
---|
| 10350 | + return pb->cpu_cnt; |
---|
| 10351 | +} |
---|
| 10352 | + |
---|
| 10353 | +/* |
---|
| 10354 | + * Return perf_event FD of a ring buffer in *buf_idx* slot of |
---|
| 10355 | + * PERF_EVENT_ARRAY BPF map. This FD can be polled for new data using |
---|
| 10356 | + * select()/poll()/epoll() Linux syscalls. |
---|
| 10357 | + */ |
---|
| 10358 | +int perf_buffer__buffer_fd(const struct perf_buffer *pb, size_t buf_idx) |
---|
| 10359 | +{ |
---|
| 10360 | + struct perf_cpu_buf *cpu_buf; |
---|
| 10361 | + |
---|
| 10362 | + if (buf_idx >= pb->cpu_cnt) |
---|
| 10363 | + return -EINVAL; |
---|
| 10364 | + |
---|
| 10365 | + cpu_buf = pb->cpu_bufs[buf_idx]; |
---|
| 10366 | + if (!cpu_buf) |
---|
| 10367 | + return -ENOENT; |
---|
| 10368 | + |
---|
| 10369 | + return cpu_buf->fd; |
---|
| 10370 | +} |
---|
| 10371 | + |
---|
| 10372 | +/* |
---|
| 10373 | + * Consume data from perf ring buffer corresponding to slot *buf_idx* in |
---|
| 10374 | + * PERF_EVENT_ARRAY BPF map without waiting/polling. If there is no data to |
---|
| 10375 | + * consume, do nothing and return success. |
---|
| 10376 | + * Returns: |
---|
| 10377 | + * - 0 on success; |
---|
| 10378 | + * - <0 on failure. |
---|
| 10379 | + */ |
---|
| 10380 | +int perf_buffer__consume_buffer(struct perf_buffer *pb, size_t buf_idx) |
---|
| 10381 | +{ |
---|
| 10382 | + struct perf_cpu_buf *cpu_buf; |
---|
| 10383 | + |
---|
| 10384 | + if (buf_idx >= pb->cpu_cnt) |
---|
| 10385 | + return -EINVAL; |
---|
| 10386 | + |
---|
| 10387 | + cpu_buf = pb->cpu_bufs[buf_idx]; |
---|
| 10388 | + if (!cpu_buf) |
---|
| 10389 | + return -ENOENT; |
---|
| 10390 | + |
---|
| 10391 | + return perf_buffer__process_records(pb, cpu_buf); |
---|
| 10392 | +} |
---|
| 10393 | + |
---|
| 10394 | +int perf_buffer__consume(struct perf_buffer *pb) |
---|
| 10395 | +{ |
---|
| 10396 | + int i, err; |
---|
| 10397 | + |
---|
| 10398 | + for (i = 0; i < pb->cpu_cnt; i++) { |
---|
| 10399 | + struct perf_cpu_buf *cpu_buf = pb->cpu_bufs[i]; |
---|
| 10400 | + |
---|
| 10401 | + if (!cpu_buf) |
---|
| 10402 | + continue; |
---|
| 10403 | + |
---|
| 10404 | + err = perf_buffer__process_records(pb, cpu_buf); |
---|
| 10405 | + if (err) { |
---|
| 10406 | + pr_warn("perf_buffer: failed to process records in buffer #%d: %d\n", i, err); |
---|
| 10407 | + return err; |
---|
| 10408 | + } |
---|
| 10409 | + } |
---|
| 10410 | + return 0; |
---|
| 10411 | +} |
---|
| 10412 | + |
---|
| 10413 | +struct bpf_prog_info_array_desc { |
---|
| 10414 | + int array_offset; /* e.g. offset of jited_prog_insns */ |
---|
| 10415 | + int count_offset; /* e.g. offset of jited_prog_len */ |
---|
| 10416 | + int size_offset; /* > 0: offset of rec size, |
---|
| 10417 | + * < 0: fix size of -size_offset |
---|
| 10418 | + */ |
---|
| 10419 | +}; |
---|
| 10420 | + |
---|
| 10421 | +static struct bpf_prog_info_array_desc bpf_prog_info_array_desc[] = { |
---|
| 10422 | + [BPF_PROG_INFO_JITED_INSNS] = { |
---|
| 10423 | + offsetof(struct bpf_prog_info, jited_prog_insns), |
---|
| 10424 | + offsetof(struct bpf_prog_info, jited_prog_len), |
---|
| 10425 | + -1, |
---|
| 10426 | + }, |
---|
| 10427 | + [BPF_PROG_INFO_XLATED_INSNS] = { |
---|
| 10428 | + offsetof(struct bpf_prog_info, xlated_prog_insns), |
---|
| 10429 | + offsetof(struct bpf_prog_info, xlated_prog_len), |
---|
| 10430 | + -1, |
---|
| 10431 | + }, |
---|
| 10432 | + [BPF_PROG_INFO_MAP_IDS] = { |
---|
| 10433 | + offsetof(struct bpf_prog_info, map_ids), |
---|
| 10434 | + offsetof(struct bpf_prog_info, nr_map_ids), |
---|
| 10435 | + -(int)sizeof(__u32), |
---|
| 10436 | + }, |
---|
| 10437 | + [BPF_PROG_INFO_JITED_KSYMS] = { |
---|
| 10438 | + offsetof(struct bpf_prog_info, jited_ksyms), |
---|
| 10439 | + offsetof(struct bpf_prog_info, nr_jited_ksyms), |
---|
| 10440 | + -(int)sizeof(__u64), |
---|
| 10441 | + }, |
---|
| 10442 | + [BPF_PROG_INFO_JITED_FUNC_LENS] = { |
---|
| 10443 | + offsetof(struct bpf_prog_info, jited_func_lens), |
---|
| 10444 | + offsetof(struct bpf_prog_info, nr_jited_func_lens), |
---|
| 10445 | + -(int)sizeof(__u32), |
---|
| 10446 | + }, |
---|
| 10447 | + [BPF_PROG_INFO_FUNC_INFO] = { |
---|
| 10448 | + offsetof(struct bpf_prog_info, func_info), |
---|
| 10449 | + offsetof(struct bpf_prog_info, nr_func_info), |
---|
| 10450 | + offsetof(struct bpf_prog_info, func_info_rec_size), |
---|
| 10451 | + }, |
---|
| 10452 | + [BPF_PROG_INFO_LINE_INFO] = { |
---|
| 10453 | + offsetof(struct bpf_prog_info, line_info), |
---|
| 10454 | + offsetof(struct bpf_prog_info, nr_line_info), |
---|
| 10455 | + offsetof(struct bpf_prog_info, line_info_rec_size), |
---|
| 10456 | + }, |
---|
| 10457 | + [BPF_PROG_INFO_JITED_LINE_INFO] = { |
---|
| 10458 | + offsetof(struct bpf_prog_info, jited_line_info), |
---|
| 10459 | + offsetof(struct bpf_prog_info, nr_jited_line_info), |
---|
| 10460 | + offsetof(struct bpf_prog_info, jited_line_info_rec_size), |
---|
| 10461 | + }, |
---|
| 10462 | + [BPF_PROG_INFO_PROG_TAGS] = { |
---|
| 10463 | + offsetof(struct bpf_prog_info, prog_tags), |
---|
| 10464 | + offsetof(struct bpf_prog_info, nr_prog_tags), |
---|
| 10465 | + -(int)sizeof(__u8) * BPF_TAG_SIZE, |
---|
| 10466 | + }, |
---|
| 10467 | + |
---|
| 10468 | +}; |
---|
| 10469 | + |
---|
| 10470 | +static __u32 bpf_prog_info_read_offset_u32(struct bpf_prog_info *info, |
---|
| 10471 | + int offset) |
---|
| 10472 | +{ |
---|
| 10473 | + __u32 *array = (__u32 *)info; |
---|
| 10474 | + |
---|
| 10475 | + if (offset >= 0) |
---|
| 10476 | + return array[offset / sizeof(__u32)]; |
---|
| 10477 | + return -(int)offset; |
---|
| 10478 | +} |
---|
| 10479 | + |
---|
| 10480 | +static __u64 bpf_prog_info_read_offset_u64(struct bpf_prog_info *info, |
---|
| 10481 | + int offset) |
---|
| 10482 | +{ |
---|
| 10483 | + __u64 *array = (__u64 *)info; |
---|
| 10484 | + |
---|
| 10485 | + if (offset >= 0) |
---|
| 10486 | + return array[offset / sizeof(__u64)]; |
---|
| 10487 | + return -(int)offset; |
---|
| 10488 | +} |
---|
| 10489 | + |
---|
| 10490 | +static void bpf_prog_info_set_offset_u32(struct bpf_prog_info *info, int offset, |
---|
| 10491 | + __u32 val) |
---|
| 10492 | +{ |
---|
| 10493 | + __u32 *array = (__u32 *)info; |
---|
| 10494 | + |
---|
| 10495 | + if (offset >= 0) |
---|
| 10496 | + array[offset / sizeof(__u32)] = val; |
---|
| 10497 | +} |
---|
| 10498 | + |
---|
| 10499 | +static void bpf_prog_info_set_offset_u64(struct bpf_prog_info *info, int offset, |
---|
| 10500 | + __u64 val) |
---|
| 10501 | +{ |
---|
| 10502 | + __u64 *array = (__u64 *)info; |
---|
| 10503 | + |
---|
| 10504 | + if (offset >= 0) |
---|
| 10505 | + array[offset / sizeof(__u64)] = val; |
---|
| 10506 | +} |
---|
| 10507 | + |
---|
| 10508 | +struct bpf_prog_info_linear * |
---|
| 10509 | +bpf_program__get_prog_info_linear(int fd, __u64 arrays) |
---|
| 10510 | +{ |
---|
| 10511 | + struct bpf_prog_info_linear *info_linear; |
---|
| 10512 | + struct bpf_prog_info info = {}; |
---|
| 10513 | + __u32 info_len = sizeof(info); |
---|
| 10514 | + __u32 data_len = 0; |
---|
| 10515 | + int i, err; |
---|
| 10516 | + void *ptr; |
---|
| 10517 | + |
---|
| 10518 | + if (arrays >> BPF_PROG_INFO_LAST_ARRAY) |
---|
| 10519 | + return ERR_PTR(-EINVAL); |
---|
| 10520 | + |
---|
| 10521 | + /* step 1: get array dimensions */ |
---|
| 10522 | + err = bpf_obj_get_info_by_fd(fd, &info, &info_len); |
---|
| 10523 | + if (err) { |
---|
| 10524 | + pr_debug("can't get prog info: %s", strerror(errno)); |
---|
| 10525 | + return ERR_PTR(-EFAULT); |
---|
| 10526 | + } |
---|
| 10527 | + |
---|
| 10528 | + /* step 2: calculate total size of all arrays */ |
---|
| 10529 | + for (i = BPF_PROG_INFO_FIRST_ARRAY; i < BPF_PROG_INFO_LAST_ARRAY; ++i) { |
---|
| 10530 | + bool include_array = (arrays & (1UL << i)) > 0; |
---|
| 10531 | + struct bpf_prog_info_array_desc *desc; |
---|
| 10532 | + __u32 count, size; |
---|
| 10533 | + |
---|
| 10534 | + desc = bpf_prog_info_array_desc + i; |
---|
| 10535 | + |
---|
| 10536 | + /* kernel is too old to support this field */ |
---|
| 10537 | + if (info_len < desc->array_offset + sizeof(__u32) || |
---|
| 10538 | + info_len < desc->count_offset + sizeof(__u32) || |
---|
| 10539 | + (desc->size_offset > 0 && info_len < desc->size_offset)) |
---|
| 10540 | + include_array = false; |
---|
| 10541 | + |
---|
| 10542 | + if (!include_array) { |
---|
| 10543 | + arrays &= ~(1UL << i); /* clear the bit */ |
---|
| 10544 | + continue; |
---|
| 10545 | + } |
---|
| 10546 | + |
---|
| 10547 | + count = bpf_prog_info_read_offset_u32(&info, desc->count_offset); |
---|
| 10548 | + size = bpf_prog_info_read_offset_u32(&info, desc->size_offset); |
---|
| 10549 | + |
---|
| 10550 | + data_len += count * size; |
---|
| 10551 | + } |
---|
| 10552 | + |
---|
| 10553 | + /* step 3: allocate continuous memory */ |
---|
| 10554 | + data_len = roundup(data_len, sizeof(__u64)); |
---|
| 10555 | + info_linear = malloc(sizeof(struct bpf_prog_info_linear) + data_len); |
---|
| 10556 | + if (!info_linear) |
---|
| 10557 | + return ERR_PTR(-ENOMEM); |
---|
| 10558 | + |
---|
| 10559 | + /* step 4: fill data to info_linear->info */ |
---|
| 10560 | + info_linear->arrays = arrays; |
---|
| 10561 | + memset(&info_linear->info, 0, sizeof(info)); |
---|
| 10562 | + ptr = info_linear->data; |
---|
| 10563 | + |
---|
| 10564 | + for (i = BPF_PROG_INFO_FIRST_ARRAY; i < BPF_PROG_INFO_LAST_ARRAY; ++i) { |
---|
| 10565 | + struct bpf_prog_info_array_desc *desc; |
---|
| 10566 | + __u32 count, size; |
---|
| 10567 | + |
---|
| 10568 | + if ((arrays & (1UL << i)) == 0) |
---|
| 10569 | + continue; |
---|
| 10570 | + |
---|
| 10571 | + desc = bpf_prog_info_array_desc + i; |
---|
| 10572 | + count = bpf_prog_info_read_offset_u32(&info, desc->count_offset); |
---|
| 10573 | + size = bpf_prog_info_read_offset_u32(&info, desc->size_offset); |
---|
| 10574 | + bpf_prog_info_set_offset_u32(&info_linear->info, |
---|
| 10575 | + desc->count_offset, count); |
---|
| 10576 | + bpf_prog_info_set_offset_u32(&info_linear->info, |
---|
| 10577 | + desc->size_offset, size); |
---|
| 10578 | + bpf_prog_info_set_offset_u64(&info_linear->info, |
---|
| 10579 | + desc->array_offset, |
---|
| 10580 | + ptr_to_u64(ptr)); |
---|
| 10581 | + ptr += count * size; |
---|
| 10582 | + } |
---|
| 10583 | + |
---|
| 10584 | + /* step 5: call syscall again to get required arrays */ |
---|
| 10585 | + err = bpf_obj_get_info_by_fd(fd, &info_linear->info, &info_len); |
---|
| 10586 | + if (err) { |
---|
| 10587 | + pr_debug("can't get prog info: %s", strerror(errno)); |
---|
| 10588 | + free(info_linear); |
---|
| 10589 | + return ERR_PTR(-EFAULT); |
---|
| 10590 | + } |
---|
| 10591 | + |
---|
| 10592 | + /* step 6: verify the data */ |
---|
| 10593 | + for (i = BPF_PROG_INFO_FIRST_ARRAY; i < BPF_PROG_INFO_LAST_ARRAY; ++i) { |
---|
| 10594 | + struct bpf_prog_info_array_desc *desc; |
---|
| 10595 | + __u32 v1, v2; |
---|
| 10596 | + |
---|
| 10597 | + if ((arrays & (1UL << i)) == 0) |
---|
| 10598 | + continue; |
---|
| 10599 | + |
---|
| 10600 | + desc = bpf_prog_info_array_desc + i; |
---|
| 10601 | + v1 = bpf_prog_info_read_offset_u32(&info, desc->count_offset); |
---|
| 10602 | + v2 = bpf_prog_info_read_offset_u32(&info_linear->info, |
---|
| 10603 | + desc->count_offset); |
---|
| 10604 | + if (v1 != v2) |
---|
| 10605 | + pr_warn("%s: mismatch in element count\n", __func__); |
---|
| 10606 | + |
---|
| 10607 | + v1 = bpf_prog_info_read_offset_u32(&info, desc->size_offset); |
---|
| 10608 | + v2 = bpf_prog_info_read_offset_u32(&info_linear->info, |
---|
| 10609 | + desc->size_offset); |
---|
| 10610 | + if (v1 != v2) |
---|
| 10611 | + pr_warn("%s: mismatch in rec size\n", __func__); |
---|
| 10612 | + } |
---|
| 10613 | + |
---|
| 10614 | + /* step 7: update info_len and data_len */ |
---|
| 10615 | + info_linear->info_len = sizeof(struct bpf_prog_info); |
---|
| 10616 | + info_linear->data_len = data_len; |
---|
| 10617 | + |
---|
| 10618 | + return info_linear; |
---|
| 10619 | +} |
---|
| 10620 | + |
---|
| 10621 | +void bpf_program__bpil_addr_to_offs(struct bpf_prog_info_linear *info_linear) |
---|
| 10622 | +{ |
---|
| 10623 | + int i; |
---|
| 10624 | + |
---|
| 10625 | + for (i = BPF_PROG_INFO_FIRST_ARRAY; i < BPF_PROG_INFO_LAST_ARRAY; ++i) { |
---|
| 10626 | + struct bpf_prog_info_array_desc *desc; |
---|
| 10627 | + __u64 addr, offs; |
---|
| 10628 | + |
---|
| 10629 | + if ((info_linear->arrays & (1UL << i)) == 0) |
---|
| 10630 | + continue; |
---|
| 10631 | + |
---|
| 10632 | + desc = bpf_prog_info_array_desc + i; |
---|
| 10633 | + addr = bpf_prog_info_read_offset_u64(&info_linear->info, |
---|
| 10634 | + desc->array_offset); |
---|
| 10635 | + offs = addr - ptr_to_u64(info_linear->data); |
---|
| 10636 | + bpf_prog_info_set_offset_u64(&info_linear->info, |
---|
| 10637 | + desc->array_offset, offs); |
---|
| 10638 | + } |
---|
| 10639 | +} |
---|
| 10640 | + |
---|
| 10641 | +void bpf_program__bpil_offs_to_addr(struct bpf_prog_info_linear *info_linear) |
---|
| 10642 | +{ |
---|
| 10643 | + int i; |
---|
| 10644 | + |
---|
| 10645 | + for (i = BPF_PROG_INFO_FIRST_ARRAY; i < BPF_PROG_INFO_LAST_ARRAY; ++i) { |
---|
| 10646 | + struct bpf_prog_info_array_desc *desc; |
---|
| 10647 | + __u64 addr, offs; |
---|
| 10648 | + |
---|
| 10649 | + if ((info_linear->arrays & (1UL << i)) == 0) |
---|
| 10650 | + continue; |
---|
| 10651 | + |
---|
| 10652 | + desc = bpf_prog_info_array_desc + i; |
---|
| 10653 | + offs = bpf_prog_info_read_offset_u64(&info_linear->info, |
---|
| 10654 | + desc->array_offset); |
---|
| 10655 | + addr = offs + ptr_to_u64(info_linear->data); |
---|
| 10656 | + bpf_prog_info_set_offset_u64(&info_linear->info, |
---|
| 10657 | + desc->array_offset, addr); |
---|
| 10658 | + } |
---|
| 10659 | +} |
---|
| 10660 | + |
---|
| 10661 | +int bpf_program__set_attach_target(struct bpf_program *prog, |
---|
| 10662 | + int attach_prog_fd, |
---|
| 10663 | + const char *attach_func_name) |
---|
| 10664 | +{ |
---|
| 10665 | + int btf_id; |
---|
| 10666 | + |
---|
| 10667 | + if (!prog || attach_prog_fd < 0 || !attach_func_name) |
---|
| 10668 | + return -EINVAL; |
---|
| 10669 | + |
---|
| 10670 | + if (attach_prog_fd) |
---|
| 10671 | + btf_id = libbpf_find_prog_btf_id(attach_func_name, |
---|
| 10672 | + attach_prog_fd); |
---|
| 10673 | + else |
---|
| 10674 | + btf_id = libbpf_find_vmlinux_btf_id(attach_func_name, |
---|
| 10675 | + prog->expected_attach_type); |
---|
| 10676 | + |
---|
| 10677 | + if (btf_id < 0) |
---|
| 10678 | + return btf_id; |
---|
| 10679 | + |
---|
| 10680 | + prog->attach_btf_id = btf_id; |
---|
| 10681 | + prog->attach_prog_fd = attach_prog_fd; |
---|
| 10682 | + return 0; |
---|
| 10683 | +} |
---|
| 10684 | + |
---|
| 10685 | +int parse_cpu_mask_str(const char *s, bool **mask, int *mask_sz) |
---|
| 10686 | +{ |
---|
| 10687 | + int err = 0, n, len, start, end = -1; |
---|
| 10688 | + bool *tmp; |
---|
| 10689 | + |
---|
| 10690 | + *mask = NULL; |
---|
| 10691 | + *mask_sz = 0; |
---|
| 10692 | + |
---|
| 10693 | + /* Each sub string separated by ',' has format \d+-\d+ or \d+ */ |
---|
| 10694 | + while (*s) { |
---|
| 10695 | + if (*s == ',' || *s == '\n') { |
---|
| 10696 | + s++; |
---|
| 10697 | + continue; |
---|
| 10698 | + } |
---|
| 10699 | + n = sscanf(s, "%d%n-%d%n", &start, &len, &end, &len); |
---|
| 10700 | + if (n <= 0 || n > 2) { |
---|
| 10701 | + pr_warn("Failed to get CPU range %s: %d\n", s, n); |
---|
| 10702 | + err = -EINVAL; |
---|
| 10703 | + goto cleanup; |
---|
| 10704 | + } else if (n == 1) { |
---|
| 10705 | + end = start; |
---|
| 10706 | + } |
---|
| 10707 | + if (start < 0 || start > end) { |
---|
| 10708 | + pr_warn("Invalid CPU range [%d,%d] in %s\n", |
---|
| 10709 | + start, end, s); |
---|
| 10710 | + err = -EINVAL; |
---|
| 10711 | + goto cleanup; |
---|
| 10712 | + } |
---|
| 10713 | + tmp = realloc(*mask, end + 1); |
---|
| 10714 | + if (!tmp) { |
---|
| 10715 | + err = -ENOMEM; |
---|
| 10716 | + goto cleanup; |
---|
| 10717 | + } |
---|
| 10718 | + *mask = tmp; |
---|
| 10719 | + memset(tmp + *mask_sz, 0, start - *mask_sz); |
---|
| 10720 | + memset(tmp + start, 1, end - start + 1); |
---|
| 10721 | + *mask_sz = end + 1; |
---|
| 10722 | + s += len; |
---|
| 10723 | + } |
---|
| 10724 | + if (!*mask_sz) { |
---|
| 10725 | + pr_warn("Empty CPU range\n"); |
---|
| 10726 | + return -EINVAL; |
---|
| 10727 | + } |
---|
| 10728 | + return 0; |
---|
| 10729 | +cleanup: |
---|
| 10730 | + free(*mask); |
---|
| 10731 | + *mask = NULL; |
---|
| 10732 | + return err; |
---|
| 10733 | +} |
---|
| 10734 | + |
---|
| 10735 | +int parse_cpu_mask_file(const char *fcpu, bool **mask, int *mask_sz) |
---|
| 10736 | +{ |
---|
| 10737 | + int fd, err = 0, len; |
---|
| 10738 | + char buf[128]; |
---|
| 10739 | + |
---|
| 10740 | + fd = open(fcpu, O_RDONLY); |
---|
| 10741 | + if (fd < 0) { |
---|
| 10742 | + err = -errno; |
---|
| 10743 | + pr_warn("Failed to open cpu mask file %s: %d\n", fcpu, err); |
---|
| 10744 | + return err; |
---|
| 10745 | + } |
---|
| 10746 | + len = read(fd, buf, sizeof(buf)); |
---|
| 10747 | + close(fd); |
---|
| 10748 | + if (len <= 0) { |
---|
| 10749 | + err = len ? -errno : -EINVAL; |
---|
| 10750 | + pr_warn("Failed to read cpu mask from %s: %d\n", fcpu, err); |
---|
| 10751 | + return err; |
---|
| 10752 | + } |
---|
| 10753 | + if (len >= sizeof(buf)) { |
---|
| 10754 | + pr_warn("CPU mask is too big in file %s\n", fcpu); |
---|
| 10755 | + return -E2BIG; |
---|
| 10756 | + } |
---|
| 10757 | + buf[len] = '\0'; |
---|
| 10758 | + |
---|
| 10759 | + return parse_cpu_mask_str(buf, mask, mask_sz); |
---|
| 10760 | +} |
---|
| 10761 | + |
---|
| 10762 | +int libbpf_num_possible_cpus(void) |
---|
| 10763 | +{ |
---|
| 10764 | + static const char *fcpu = "/sys/devices/system/cpu/possible"; |
---|
| 10765 | + static int cpus; |
---|
| 10766 | + int err, n, i, tmp_cpus; |
---|
| 10767 | + bool *mask; |
---|
| 10768 | + |
---|
| 10769 | + tmp_cpus = READ_ONCE(cpus); |
---|
| 10770 | + if (tmp_cpus > 0) |
---|
| 10771 | + return tmp_cpus; |
---|
| 10772 | + |
---|
| 10773 | + err = parse_cpu_mask_file(fcpu, &mask, &n); |
---|
| 10774 | + if (err) |
---|
| 10775 | + return err; |
---|
| 10776 | + |
---|
| 10777 | + tmp_cpus = 0; |
---|
| 10778 | + for (i = 0; i < n; i++) { |
---|
| 10779 | + if (mask[i]) |
---|
| 10780 | + tmp_cpus++; |
---|
| 10781 | + } |
---|
| 10782 | + free(mask); |
---|
| 10783 | + |
---|
| 10784 | + WRITE_ONCE(cpus, tmp_cpus); |
---|
| 10785 | + return tmp_cpus; |
---|
| 10786 | +} |
---|
| 10787 | + |
---|
| 10788 | +int bpf_object__open_skeleton(struct bpf_object_skeleton *s, |
---|
| 10789 | + const struct bpf_object_open_opts *opts) |
---|
| 10790 | +{ |
---|
| 10791 | + DECLARE_LIBBPF_OPTS(bpf_object_open_opts, skel_opts, |
---|
| 10792 | + .object_name = s->name, |
---|
| 10793 | + ); |
---|
| 10794 | + struct bpf_object *obj; |
---|
| 10795 | + int i; |
---|
| 10796 | + |
---|
| 10797 | + /* Attempt to preserve opts->object_name, unless overriden by user |
---|
| 10798 | + * explicitly. Overwriting object name for skeletons is discouraged, |
---|
| 10799 | + * as it breaks global data maps, because they contain object name |
---|
| 10800 | + * prefix as their own map name prefix. When skeleton is generated, |
---|
| 10801 | + * bpftool is making an assumption that this name will stay the same. |
---|
| 10802 | + */ |
---|
| 10803 | + if (opts) { |
---|
| 10804 | + memcpy(&skel_opts, opts, sizeof(*opts)); |
---|
| 10805 | + if (!opts->object_name) |
---|
| 10806 | + skel_opts.object_name = s->name; |
---|
| 10807 | + } |
---|
| 10808 | + |
---|
| 10809 | + obj = bpf_object__open_mem(s->data, s->data_sz, &skel_opts); |
---|
| 10810 | + if (IS_ERR(obj)) { |
---|
| 10811 | + pr_warn("failed to initialize skeleton BPF object '%s': %ld\n", |
---|
| 10812 | + s->name, PTR_ERR(obj)); |
---|
| 10813 | + return PTR_ERR(obj); |
---|
| 10814 | + } |
---|
| 10815 | + |
---|
| 10816 | + *s->obj = obj; |
---|
| 10817 | + |
---|
| 10818 | + for (i = 0; i < s->map_cnt; i++) { |
---|
| 10819 | + struct bpf_map **map = s->maps[i].map; |
---|
| 10820 | + const char *name = s->maps[i].name; |
---|
| 10821 | + void **mmaped = s->maps[i].mmaped; |
---|
| 10822 | + |
---|
| 10823 | + *map = bpf_object__find_map_by_name(obj, name); |
---|
| 10824 | + if (!*map) { |
---|
| 10825 | + pr_warn("failed to find skeleton map '%s'\n", name); |
---|
| 10826 | + return -ESRCH; |
---|
| 10827 | + } |
---|
| 10828 | + |
---|
| 10829 | + /* externs shouldn't be pre-setup from user code */ |
---|
| 10830 | + if (mmaped && (*map)->libbpf_type != LIBBPF_MAP_KCONFIG) |
---|
| 10831 | + *mmaped = (*map)->mmaped; |
---|
| 10832 | + } |
---|
| 10833 | + |
---|
| 10834 | + for (i = 0; i < s->prog_cnt; i++) { |
---|
| 10835 | + struct bpf_program **prog = s->progs[i].prog; |
---|
| 10836 | + const char *name = s->progs[i].name; |
---|
| 10837 | + |
---|
| 10838 | + *prog = bpf_object__find_program_by_name(obj, name); |
---|
| 10839 | + if (!*prog) { |
---|
| 10840 | + pr_warn("failed to find skeleton program '%s'\n", name); |
---|
| 10841 | + return -ESRCH; |
---|
| 10842 | + } |
---|
| 10843 | + } |
---|
| 10844 | + |
---|
| 10845 | + return 0; |
---|
| 10846 | +} |
---|
| 10847 | + |
---|
| 10848 | +int bpf_object__load_skeleton(struct bpf_object_skeleton *s) |
---|
| 10849 | +{ |
---|
| 10850 | + int i, err; |
---|
| 10851 | + |
---|
| 10852 | + err = bpf_object__load(*s->obj); |
---|
| 10853 | + if (err) { |
---|
| 10854 | + pr_warn("failed to load BPF skeleton '%s': %d\n", s->name, err); |
---|
| 10855 | + return err; |
---|
| 10856 | + } |
---|
| 10857 | + |
---|
| 10858 | + for (i = 0; i < s->map_cnt; i++) { |
---|
| 10859 | + struct bpf_map *map = *s->maps[i].map; |
---|
| 10860 | + size_t mmap_sz = bpf_map_mmap_sz(map); |
---|
| 10861 | + int prot, map_fd = bpf_map__fd(map); |
---|
| 10862 | + void **mmaped = s->maps[i].mmaped; |
---|
| 10863 | + |
---|
| 10864 | + if (!mmaped) |
---|
| 10865 | + continue; |
---|
| 10866 | + |
---|
| 10867 | + if (!(map->def.map_flags & BPF_F_MMAPABLE)) { |
---|
| 10868 | + *mmaped = NULL; |
---|
| 10869 | + continue; |
---|
| 10870 | + } |
---|
| 10871 | + |
---|
| 10872 | + if (map->def.map_flags & BPF_F_RDONLY_PROG) |
---|
| 10873 | + prot = PROT_READ; |
---|
| 10874 | + else |
---|
| 10875 | + prot = PROT_READ | PROT_WRITE; |
---|
| 10876 | + |
---|
| 10877 | + /* Remap anonymous mmap()-ed "map initialization image" as |
---|
| 10878 | + * a BPF map-backed mmap()-ed memory, but preserving the same |
---|
| 10879 | + * memory address. This will cause kernel to change process' |
---|
| 10880 | + * page table to point to a different piece of kernel memory, |
---|
| 10881 | + * but from userspace point of view memory address (and its |
---|
| 10882 | + * contents, being identical at this point) will stay the |
---|
| 10883 | + * same. This mapping will be released by bpf_object__close() |
---|
| 10884 | + * as per normal clean up procedure, so we don't need to worry |
---|
| 10885 | + * about it from skeleton's clean up perspective. |
---|
| 10886 | + */ |
---|
| 10887 | + *mmaped = mmap(map->mmaped, mmap_sz, prot, |
---|
| 10888 | + MAP_SHARED | MAP_FIXED, map_fd, 0); |
---|
| 10889 | + if (*mmaped == MAP_FAILED) { |
---|
| 10890 | + err = -errno; |
---|
| 10891 | + *mmaped = NULL; |
---|
| 10892 | + pr_warn("failed to re-mmap() map '%s': %d\n", |
---|
| 10893 | + bpf_map__name(map), err); |
---|
| 10894 | + return err; |
---|
| 10895 | + } |
---|
| 10896 | + } |
---|
| 10897 | + |
---|
| 10898 | + return 0; |
---|
| 10899 | +} |
---|
| 10900 | + |
---|
| 10901 | +int bpf_object__attach_skeleton(struct bpf_object_skeleton *s) |
---|
| 10902 | +{ |
---|
| 10903 | + int i; |
---|
| 10904 | + |
---|
| 10905 | + for (i = 0; i < s->prog_cnt; i++) { |
---|
| 10906 | + struct bpf_program *prog = *s->progs[i].prog; |
---|
| 10907 | + struct bpf_link **link = s->progs[i].link; |
---|
| 10908 | + const struct bpf_sec_def *sec_def; |
---|
| 10909 | + |
---|
| 10910 | + if (!prog->load) |
---|
| 10911 | + continue; |
---|
| 10912 | + |
---|
| 10913 | + sec_def = find_sec_def(prog->sec_name); |
---|
| 10914 | + if (!sec_def || !sec_def->attach_fn) |
---|
| 10915 | + continue; |
---|
| 10916 | + |
---|
| 10917 | + *link = sec_def->attach_fn(sec_def, prog); |
---|
| 10918 | + if (IS_ERR(*link)) { |
---|
| 10919 | + pr_warn("failed to auto-attach program '%s': %ld\n", |
---|
| 10920 | + bpf_program__name(prog), PTR_ERR(*link)); |
---|
| 10921 | + return PTR_ERR(*link); |
---|
| 10922 | + } |
---|
| 10923 | + } |
---|
| 10924 | + |
---|
| 10925 | + return 0; |
---|
| 10926 | +} |
---|
| 10927 | + |
---|
| 10928 | +void bpf_object__detach_skeleton(struct bpf_object_skeleton *s) |
---|
| 10929 | +{ |
---|
| 10930 | + int i; |
---|
| 10931 | + |
---|
| 10932 | + for (i = 0; i < s->prog_cnt; i++) { |
---|
| 10933 | + struct bpf_link **link = s->progs[i].link; |
---|
| 10934 | + |
---|
| 10935 | + bpf_link__destroy(*link); |
---|
| 10936 | + *link = NULL; |
---|
| 10937 | + } |
---|
| 10938 | +} |
---|
| 10939 | + |
---|
| 10940 | +void bpf_object__destroy_skeleton(struct bpf_object_skeleton *s) |
---|
| 10941 | +{ |
---|
| 10942 | + if (!s) |
---|
| 10943 | + return; |
---|
| 10944 | + |
---|
| 10945 | + if (s->progs) |
---|
| 10946 | + bpf_object__detach_skeleton(s); |
---|
| 10947 | + if (s->obj) |
---|
| 10948 | + bpf_object__close(*s->obj); |
---|
| 10949 | + free(s->maps); |
---|
| 10950 | + free(s->progs); |
---|
| 10951 | + free(s); |
---|
| 10952 | +} |
---|