// SPDX-License-Identifier: GPL-2.0
|
/*
|
* uprobes-based tracing events
|
*
|
* Copyright (C) IBM Corporation, 2010-2012
|
* Author: Srikar Dronamraju <srikar@linux.vnet.ibm.com>
|
*/
|
#define pr_fmt(fmt) "trace_uprobe: " fmt
|
|
#include <linux/security.h>
|
#include <linux/ctype.h>
|
#include <linux/module.h>
|
#include <linux/uaccess.h>
|
#include <linux/uprobes.h>
|
#include <linux/namei.h>
|
#include <linux/string.h>
|
#include <linux/rculist.h>
|
|
#include "trace_dynevent.h"
|
#include "trace_probe.h"
|
#include "trace_probe_tmpl.h"
|
|
#define UPROBE_EVENT_SYSTEM "uprobes"
|
|
struct uprobe_trace_entry_head {
|
struct trace_entry ent;
|
unsigned long vaddr[];
|
};
|
|
#define SIZEOF_TRACE_ENTRY(is_return) \
|
(sizeof(struct uprobe_trace_entry_head) + \
|
sizeof(unsigned long) * (is_return ? 2 : 1))
|
|
#define DATAOF_TRACE_ENTRY(entry, is_return) \
|
((void*)(entry) + SIZEOF_TRACE_ENTRY(is_return))
|
|
static int trace_uprobe_create(int argc, const char **argv);
|
static int trace_uprobe_show(struct seq_file *m, struct dyn_event *ev);
|
static int trace_uprobe_release(struct dyn_event *ev);
|
static bool trace_uprobe_is_busy(struct dyn_event *ev);
|
static bool trace_uprobe_match(const char *system, const char *event,
|
int argc, const char **argv, struct dyn_event *ev);
|
|
static struct dyn_event_operations trace_uprobe_ops = {
|
.create = trace_uprobe_create,
|
.show = trace_uprobe_show,
|
.is_busy = trace_uprobe_is_busy,
|
.free = trace_uprobe_release,
|
.match = trace_uprobe_match,
|
};
|
|
/*
|
* uprobe event core functions
|
*/
|
struct trace_uprobe {
|
struct dyn_event devent;
|
struct uprobe_consumer consumer;
|
struct path path;
|
struct inode *inode;
|
char *filename;
|
unsigned long offset;
|
unsigned long ref_ctr_offset;
|
unsigned long nhit;
|
struct trace_probe tp;
|
};
|
|
static bool is_trace_uprobe(struct dyn_event *ev)
|
{
|
return ev->ops == &trace_uprobe_ops;
|
}
|
|
static struct trace_uprobe *to_trace_uprobe(struct dyn_event *ev)
|
{
|
return container_of(ev, struct trace_uprobe, devent);
|
}
|
|
/**
|
* for_each_trace_uprobe - iterate over the trace_uprobe list
|
* @pos: the struct trace_uprobe * for each entry
|
* @dpos: the struct dyn_event * to use as a loop cursor
|
*/
|
#define for_each_trace_uprobe(pos, dpos) \
|
for_each_dyn_event(dpos) \
|
if (is_trace_uprobe(dpos) && (pos = to_trace_uprobe(dpos)))
|
|
#define SIZEOF_TRACE_UPROBE(n) \
|
(offsetof(struct trace_uprobe, tp.args) + \
|
(sizeof(struct probe_arg) * (n)))
|
|
static int register_uprobe_event(struct trace_uprobe *tu);
|
static int unregister_uprobe_event(struct trace_uprobe *tu);
|
|
struct uprobe_dispatch_data {
|
struct trace_uprobe *tu;
|
unsigned long bp_addr;
|
};
|
|
static int uprobe_dispatcher(struct uprobe_consumer *con, struct pt_regs *regs);
|
static int uretprobe_dispatcher(struct uprobe_consumer *con,
|
unsigned long func, struct pt_regs *regs);
|
|
#ifdef CONFIG_STACK_GROWSUP
|
static unsigned long adjust_stack_addr(unsigned long addr, unsigned int n)
|
{
|
return addr - (n * sizeof(long));
|
}
|
#else
|
static unsigned long adjust_stack_addr(unsigned long addr, unsigned int n)
|
{
|
return addr + (n * sizeof(long));
|
}
|
#endif
|
|
static unsigned long get_user_stack_nth(struct pt_regs *regs, unsigned int n)
|
{
|
unsigned long ret;
|
unsigned long addr = user_stack_pointer(regs);
|
|
addr = adjust_stack_addr(addr, n);
|
|
if (copy_from_user(&ret, (void __force __user *) addr, sizeof(ret)))
|
return 0;
|
|
return ret;
|
}
|
|
/*
|
* Uprobes-specific fetch functions
|
*/
|
static nokprobe_inline int
|
probe_mem_read(void *dest, void *src, size_t size)
|
{
|
void __user *vaddr = (void __force __user *)src;
|
|
return copy_from_user(dest, vaddr, size) ? -EFAULT : 0;
|
}
|
|
static nokprobe_inline int
|
probe_mem_read_user(void *dest, void *src, size_t size)
|
{
|
return probe_mem_read(dest, src, size);
|
}
|
|
/*
|
* Fetch a null-terminated string. Caller MUST set *(u32 *)dest with max
|
* length and relative data location.
|
*/
|
static nokprobe_inline int
|
fetch_store_string(unsigned long addr, void *dest, void *base)
|
{
|
long ret;
|
u32 loc = *(u32 *)dest;
|
int maxlen = get_loc_len(loc);
|
u8 *dst = get_loc_data(dest, base);
|
void __user *src = (void __force __user *) addr;
|
|
if (unlikely(!maxlen))
|
return -ENOMEM;
|
|
if (addr == FETCH_TOKEN_COMM)
|
ret = strlcpy(dst, current->comm, maxlen);
|
else
|
ret = strncpy_from_user(dst, src, maxlen);
|
if (ret >= 0) {
|
if (ret == maxlen)
|
dst[ret - 1] = '\0';
|
else
|
/*
|
* Include the terminating null byte. In this case it
|
* was copied by strncpy_from_user but not accounted
|
* for in ret.
|
*/
|
ret++;
|
*(u32 *)dest = make_data_loc(ret, (void *)dst - base);
|
}
|
|
return ret;
|
}
|
|
static nokprobe_inline int
|
fetch_store_string_user(unsigned long addr, void *dest, void *base)
|
{
|
return fetch_store_string(addr, dest, base);
|
}
|
|
/* Return the length of string -- including null terminal byte */
|
static nokprobe_inline int
|
fetch_store_strlen(unsigned long addr)
|
{
|
int len;
|
void __user *vaddr = (void __force __user *) addr;
|
|
if (addr == FETCH_TOKEN_COMM)
|
len = strlen(current->comm) + 1;
|
else
|
len = strnlen_user(vaddr, MAX_STRING_SIZE);
|
|
return (len > MAX_STRING_SIZE) ? 0 : len;
|
}
|
|
static nokprobe_inline int
|
fetch_store_strlen_user(unsigned long addr)
|
{
|
return fetch_store_strlen(addr);
|
}
|
|
static unsigned long translate_user_vaddr(unsigned long file_offset)
|
{
|
unsigned long base_addr;
|
struct uprobe_dispatch_data *udd;
|
|
udd = (void *) current->utask->vaddr;
|
|
base_addr = udd->bp_addr - udd->tu->offset;
|
return base_addr + file_offset;
|
}
|
|
/* Note that we don't verify it, since the code does not come from user space */
|
static int
|
process_fetch_insn(struct fetch_insn *code, struct pt_regs *regs, void *dest,
|
void *base)
|
{
|
unsigned long val;
|
|
/* 1st stage: get value from context */
|
switch (code->op) {
|
case FETCH_OP_REG:
|
val = regs_get_register(regs, code->param);
|
break;
|
case FETCH_OP_STACK:
|
val = get_user_stack_nth(regs, code->param);
|
break;
|
case FETCH_OP_STACKP:
|
val = user_stack_pointer(regs);
|
break;
|
case FETCH_OP_RETVAL:
|
val = regs_return_value(regs);
|
break;
|
case FETCH_OP_IMM:
|
val = code->immediate;
|
break;
|
case FETCH_OP_COMM:
|
val = FETCH_TOKEN_COMM;
|
break;
|
case FETCH_OP_DATA:
|
val = (unsigned long)code->data;
|
break;
|
case FETCH_OP_FOFFS:
|
val = translate_user_vaddr(code->immediate);
|
break;
|
default:
|
return -EILSEQ;
|
}
|
code++;
|
|
return process_fetch_insn_bottom(code, val, dest, base);
|
}
|
NOKPROBE_SYMBOL(process_fetch_insn)
|
|
static inline void init_trace_uprobe_filter(struct trace_uprobe_filter *filter)
|
{
|
rwlock_init(&filter->rwlock);
|
filter->nr_systemwide = 0;
|
INIT_LIST_HEAD(&filter->perf_events);
|
}
|
|
static inline bool uprobe_filter_is_empty(struct trace_uprobe_filter *filter)
|
{
|
return !filter->nr_systemwide && list_empty(&filter->perf_events);
|
}
|
|
static inline bool is_ret_probe(struct trace_uprobe *tu)
|
{
|
return tu->consumer.ret_handler != NULL;
|
}
|
|
static bool trace_uprobe_is_busy(struct dyn_event *ev)
|
{
|
struct trace_uprobe *tu = to_trace_uprobe(ev);
|
|
return trace_probe_is_enabled(&tu->tp);
|
}
|
|
static bool trace_uprobe_match_command_head(struct trace_uprobe *tu,
|
int argc, const char **argv)
|
{
|
char buf[MAX_ARGSTR_LEN + 1];
|
int len;
|
|
if (!argc)
|
return true;
|
|
len = strlen(tu->filename);
|
if (strncmp(tu->filename, argv[0], len) || argv[0][len] != ':')
|
return false;
|
|
if (tu->ref_ctr_offset == 0)
|
snprintf(buf, sizeof(buf), "0x%0*lx",
|
(int)(sizeof(void *) * 2), tu->offset);
|
else
|
snprintf(buf, sizeof(buf), "0x%0*lx(0x%lx)",
|
(int)(sizeof(void *) * 2), tu->offset,
|
tu->ref_ctr_offset);
|
if (strcmp(buf, &argv[0][len + 1]))
|
return false;
|
|
argc--; argv++;
|
|
return trace_probe_match_command_args(&tu->tp, argc, argv);
|
}
|
|
static bool trace_uprobe_match(const char *system, const char *event,
|
int argc, const char **argv, struct dyn_event *ev)
|
{
|
struct trace_uprobe *tu = to_trace_uprobe(ev);
|
|
return strcmp(trace_probe_name(&tu->tp), event) == 0 &&
|
(!system || strcmp(trace_probe_group_name(&tu->tp), system) == 0) &&
|
trace_uprobe_match_command_head(tu, argc, argv);
|
}
|
|
static nokprobe_inline struct trace_uprobe *
|
trace_uprobe_primary_from_call(struct trace_event_call *call)
|
{
|
struct trace_probe *tp;
|
|
tp = trace_probe_primary_from_call(call);
|
if (WARN_ON_ONCE(!tp))
|
return NULL;
|
|
return container_of(tp, struct trace_uprobe, tp);
|
}
|
|
/*
|
* Allocate new trace_uprobe and initialize it (including uprobes).
|
*/
|
static struct trace_uprobe *
|
alloc_trace_uprobe(const char *group, const char *event, int nargs, bool is_ret)
|
{
|
struct trace_uprobe *tu;
|
int ret;
|
|
tu = kzalloc(SIZEOF_TRACE_UPROBE(nargs), GFP_KERNEL);
|
if (!tu)
|
return ERR_PTR(-ENOMEM);
|
|
ret = trace_probe_init(&tu->tp, event, group, true);
|
if (ret < 0)
|
goto error;
|
|
dyn_event_init(&tu->devent, &trace_uprobe_ops);
|
tu->consumer.handler = uprobe_dispatcher;
|
if (is_ret)
|
tu->consumer.ret_handler = uretprobe_dispatcher;
|
init_trace_uprobe_filter(tu->tp.event->filter);
|
return tu;
|
|
error:
|
kfree(tu);
|
|
return ERR_PTR(ret);
|
}
|
|
static void free_trace_uprobe(struct trace_uprobe *tu)
|
{
|
if (!tu)
|
return;
|
|
path_put(&tu->path);
|
trace_probe_cleanup(&tu->tp);
|
kfree(tu->filename);
|
kfree(tu);
|
}
|
|
static struct trace_uprobe *find_probe_event(const char *event, const char *group)
|
{
|
struct dyn_event *pos;
|
struct trace_uprobe *tu;
|
|
for_each_trace_uprobe(tu, pos)
|
if (strcmp(trace_probe_name(&tu->tp), event) == 0 &&
|
strcmp(trace_probe_group_name(&tu->tp), group) == 0)
|
return tu;
|
|
return NULL;
|
}
|
|
/* Unregister a trace_uprobe and probe_event */
|
static int unregister_trace_uprobe(struct trace_uprobe *tu)
|
{
|
int ret;
|
|
if (trace_probe_has_sibling(&tu->tp))
|
goto unreg;
|
|
ret = unregister_uprobe_event(tu);
|
if (ret)
|
return ret;
|
|
unreg:
|
dyn_event_remove(&tu->devent);
|
trace_probe_unlink(&tu->tp);
|
free_trace_uprobe(tu);
|
return 0;
|
}
|
|
static bool trace_uprobe_has_same_uprobe(struct trace_uprobe *orig,
|
struct trace_uprobe *comp)
|
{
|
struct trace_probe_event *tpe = orig->tp.event;
|
struct trace_probe *pos;
|
struct inode *comp_inode = d_real_inode(comp->path.dentry);
|
int i;
|
|
list_for_each_entry(pos, &tpe->probes, list) {
|
orig = container_of(pos, struct trace_uprobe, tp);
|
if (comp_inode != d_real_inode(orig->path.dentry) ||
|
comp->offset != orig->offset)
|
continue;
|
|
/*
|
* trace_probe_compare_arg_type() ensured that nr_args and
|
* each argument name and type are same. Let's compare comm.
|
*/
|
for (i = 0; i < orig->tp.nr_args; i++) {
|
if (strcmp(orig->tp.args[i].comm,
|
comp->tp.args[i].comm))
|
break;
|
}
|
|
if (i == orig->tp.nr_args)
|
return true;
|
}
|
|
return false;
|
}
|
|
static int append_trace_uprobe(struct trace_uprobe *tu, struct trace_uprobe *to)
|
{
|
int ret;
|
|
ret = trace_probe_compare_arg_type(&tu->tp, &to->tp);
|
if (ret) {
|
/* Note that argument starts index = 2 */
|
trace_probe_log_set_index(ret + 1);
|
trace_probe_log_err(0, DIFF_ARG_TYPE);
|
return -EEXIST;
|
}
|
if (trace_uprobe_has_same_uprobe(to, tu)) {
|
trace_probe_log_set_index(0);
|
trace_probe_log_err(0, SAME_PROBE);
|
return -EEXIST;
|
}
|
|
/* Append to existing event */
|
ret = trace_probe_append(&tu->tp, &to->tp);
|
if (!ret)
|
dyn_event_add(&tu->devent);
|
|
return ret;
|
}
|
|
/*
|
* Uprobe with multiple reference counter is not allowed. i.e.
|
* If inode and offset matches, reference counter offset *must*
|
* match as well. Though, there is one exception: If user is
|
* replacing old trace_uprobe with new one(same group/event),
|
* then we allow same uprobe with new reference counter as far
|
* as the new one does not conflict with any other existing
|
* ones.
|
*/
|
static int validate_ref_ctr_offset(struct trace_uprobe *new)
|
{
|
struct dyn_event *pos;
|
struct trace_uprobe *tmp;
|
struct inode *new_inode = d_real_inode(new->path.dentry);
|
|
for_each_trace_uprobe(tmp, pos) {
|
if (new_inode == d_real_inode(tmp->path.dentry) &&
|
new->offset == tmp->offset &&
|
new->ref_ctr_offset != tmp->ref_ctr_offset) {
|
pr_warn("Reference counter offset mismatch.");
|
return -EINVAL;
|
}
|
}
|
return 0;
|
}
|
|
/* Register a trace_uprobe and probe_event */
|
static int register_trace_uprobe(struct trace_uprobe *tu)
|
{
|
struct trace_uprobe *old_tu;
|
int ret;
|
|
mutex_lock(&event_mutex);
|
|
ret = validate_ref_ctr_offset(tu);
|
if (ret)
|
goto end;
|
|
/* register as an event */
|
old_tu = find_probe_event(trace_probe_name(&tu->tp),
|
trace_probe_group_name(&tu->tp));
|
if (old_tu) {
|
if (is_ret_probe(tu) != is_ret_probe(old_tu)) {
|
trace_probe_log_set_index(0);
|
trace_probe_log_err(0, DIFF_PROBE_TYPE);
|
ret = -EEXIST;
|
} else {
|
ret = append_trace_uprobe(tu, old_tu);
|
}
|
goto end;
|
}
|
|
ret = register_uprobe_event(tu);
|
if (ret) {
|
if (ret == -EEXIST) {
|
trace_probe_log_set_index(0);
|
trace_probe_log_err(0, EVENT_EXIST);
|
} else
|
pr_warn("Failed to register probe event(%d)\n", ret);
|
goto end;
|
}
|
|
dyn_event_add(&tu->devent);
|
|
end:
|
mutex_unlock(&event_mutex);
|
|
return ret;
|
}
|
|
/*
|
* Argument syntax:
|
* - Add uprobe: p|r[:[GRP/]EVENT] PATH:OFFSET[%return][(REF)] [FETCHARGS]
|
*/
|
static int trace_uprobe_create(int argc, const char **argv)
|
{
|
struct trace_uprobe *tu;
|
const char *event = NULL, *group = UPROBE_EVENT_SYSTEM;
|
char *arg, *filename, *rctr, *rctr_end, *tmp;
|
char buf[MAX_EVENT_NAME_LEN];
|
struct path path;
|
unsigned long offset, ref_ctr_offset;
|
bool is_return = false;
|
int i, ret;
|
|
ret = 0;
|
ref_ctr_offset = 0;
|
|
switch (argv[0][0]) {
|
case 'r':
|
is_return = true;
|
break;
|
case 'p':
|
break;
|
default:
|
return -ECANCELED;
|
}
|
|
if (argc < 2)
|
return -ECANCELED;
|
|
if (argv[0][1] == ':')
|
event = &argv[0][2];
|
|
if (!strchr(argv[1], '/'))
|
return -ECANCELED;
|
|
filename = kstrdup(argv[1], GFP_KERNEL);
|
if (!filename)
|
return -ENOMEM;
|
|
/* Find the last occurrence, in case the path contains ':' too. */
|
arg = strrchr(filename, ':');
|
if (!arg || !isdigit(arg[1])) {
|
kfree(filename);
|
return -ECANCELED;
|
}
|
|
trace_probe_log_init("trace_uprobe", argc, argv);
|
trace_probe_log_set_index(1); /* filename is the 2nd argument */
|
|
*arg++ = '\0';
|
ret = kern_path(filename, LOOKUP_FOLLOW, &path);
|
if (ret) {
|
trace_probe_log_err(0, FILE_NOT_FOUND);
|
kfree(filename);
|
trace_probe_log_clear();
|
return ret;
|
}
|
if (!d_is_reg(path.dentry)) {
|
trace_probe_log_err(0, NO_REGULAR_FILE);
|
ret = -EINVAL;
|
goto fail_address_parse;
|
}
|
|
/* Parse reference counter offset if specified. */
|
rctr = strchr(arg, '(');
|
if (rctr) {
|
rctr_end = strchr(rctr, ')');
|
if (!rctr_end) {
|
ret = -EINVAL;
|
rctr_end = rctr + strlen(rctr);
|
trace_probe_log_err(rctr_end - filename,
|
REFCNT_OPEN_BRACE);
|
goto fail_address_parse;
|
} else if (rctr_end[1] != '\0') {
|
ret = -EINVAL;
|
trace_probe_log_err(rctr_end + 1 - filename,
|
BAD_REFCNT_SUFFIX);
|
goto fail_address_parse;
|
}
|
|
*rctr++ = '\0';
|
*rctr_end = '\0';
|
ret = kstrtoul(rctr, 0, &ref_ctr_offset);
|
if (ret) {
|
trace_probe_log_err(rctr - filename, BAD_REFCNT);
|
goto fail_address_parse;
|
}
|
}
|
|
/* Check if there is %return suffix */
|
tmp = strchr(arg, '%');
|
if (tmp) {
|
if (!strcmp(tmp, "%return")) {
|
*tmp = '\0';
|
is_return = true;
|
} else {
|
trace_probe_log_err(tmp - filename, BAD_ADDR_SUFFIX);
|
ret = -EINVAL;
|
goto fail_address_parse;
|
}
|
}
|
|
/* Parse uprobe offset. */
|
ret = kstrtoul(arg, 0, &offset);
|
if (ret) {
|
trace_probe_log_err(arg - filename, BAD_UPROBE_OFFS);
|
goto fail_address_parse;
|
}
|
|
/* setup a probe */
|
trace_probe_log_set_index(0);
|
if (event) {
|
ret = traceprobe_parse_event_name(&event, &group, buf,
|
event - argv[0]);
|
if (ret)
|
goto fail_address_parse;
|
} else {
|
char *tail;
|
char *ptr;
|
|
tail = kstrdup(kbasename(filename), GFP_KERNEL);
|
if (!tail) {
|
ret = -ENOMEM;
|
goto fail_address_parse;
|
}
|
|
ptr = strpbrk(tail, ".-_");
|
if (ptr)
|
*ptr = '\0';
|
|
snprintf(buf, MAX_EVENT_NAME_LEN, "%c_%s_0x%lx", 'p', tail, offset);
|
event = buf;
|
kfree(tail);
|
}
|
|
argc -= 2;
|
argv += 2;
|
|
tu = alloc_trace_uprobe(group, event, argc, is_return);
|
if (IS_ERR(tu)) {
|
ret = PTR_ERR(tu);
|
/* This must return -ENOMEM otherwise there is a bug */
|
WARN_ON_ONCE(ret != -ENOMEM);
|
goto fail_address_parse;
|
}
|
tu->offset = offset;
|
tu->ref_ctr_offset = ref_ctr_offset;
|
tu->path = path;
|
tu->filename = filename;
|
|
/* parse arguments */
|
for (i = 0; i < argc && i < MAX_TRACE_ARGS; i++) {
|
tmp = kstrdup(argv[i], GFP_KERNEL);
|
if (!tmp) {
|
ret = -ENOMEM;
|
goto error;
|
}
|
|
trace_probe_log_set_index(i + 2);
|
ret = traceprobe_parse_probe_arg(&tu->tp, i, tmp,
|
is_return ? TPARG_FL_RETURN : 0);
|
kfree(tmp);
|
if (ret)
|
goto error;
|
}
|
|
ret = traceprobe_set_print_fmt(&tu->tp, is_ret_probe(tu));
|
if (ret < 0)
|
goto error;
|
|
ret = register_trace_uprobe(tu);
|
if (!ret)
|
goto out;
|
|
error:
|
free_trace_uprobe(tu);
|
out:
|
trace_probe_log_clear();
|
return ret;
|
|
fail_address_parse:
|
trace_probe_log_clear();
|
path_put(&path);
|
kfree(filename);
|
|
return ret;
|
}
|
|
static int create_or_delete_trace_uprobe(int argc, char **argv)
|
{
|
int ret;
|
|
if (argv[0][0] == '-')
|
return dyn_event_release(argc, argv, &trace_uprobe_ops);
|
|
ret = trace_uprobe_create(argc, (const char **)argv);
|
return ret == -ECANCELED ? -EINVAL : ret;
|
}
|
|
static int trace_uprobe_release(struct dyn_event *ev)
|
{
|
struct trace_uprobe *tu = to_trace_uprobe(ev);
|
|
return unregister_trace_uprobe(tu);
|
}
|
|
/* Probes listing interfaces */
|
static int trace_uprobe_show(struct seq_file *m, struct dyn_event *ev)
|
{
|
struct trace_uprobe *tu = to_trace_uprobe(ev);
|
char c = is_ret_probe(tu) ? 'r' : 'p';
|
int i;
|
|
seq_printf(m, "%c:%s/%s %s:0x%0*lx", c, trace_probe_group_name(&tu->tp),
|
trace_probe_name(&tu->tp), tu->filename,
|
(int)(sizeof(void *) * 2), tu->offset);
|
|
if (tu->ref_ctr_offset)
|
seq_printf(m, "(0x%lx)", tu->ref_ctr_offset);
|
|
for (i = 0; i < tu->tp.nr_args; i++)
|
seq_printf(m, " %s=%s", tu->tp.args[i].name, tu->tp.args[i].comm);
|
|
seq_putc(m, '\n');
|
return 0;
|
}
|
|
static int probes_seq_show(struct seq_file *m, void *v)
|
{
|
struct dyn_event *ev = v;
|
|
if (!is_trace_uprobe(ev))
|
return 0;
|
|
return trace_uprobe_show(m, ev);
|
}
|
|
static const struct seq_operations probes_seq_op = {
|
.start = dyn_event_seq_start,
|
.next = dyn_event_seq_next,
|
.stop = dyn_event_seq_stop,
|
.show = probes_seq_show
|
};
|
|
static int probes_open(struct inode *inode, struct file *file)
|
{
|
int ret;
|
|
ret = security_locked_down(LOCKDOWN_TRACEFS);
|
if (ret)
|
return ret;
|
|
if ((file->f_mode & FMODE_WRITE) && (file->f_flags & O_TRUNC)) {
|
ret = dyn_events_release_all(&trace_uprobe_ops);
|
if (ret)
|
return ret;
|
}
|
|
return seq_open(file, &probes_seq_op);
|
}
|
|
static ssize_t probes_write(struct file *file, const char __user *buffer,
|
size_t count, loff_t *ppos)
|
{
|
return trace_parse_run_command(file, buffer, count, ppos,
|
create_or_delete_trace_uprobe);
|
}
|
|
static const struct file_operations uprobe_events_ops = {
|
.owner = THIS_MODULE,
|
.open = probes_open,
|
.read = seq_read,
|
.llseek = seq_lseek,
|
.release = seq_release,
|
.write = probes_write,
|
};
|
|
/* Probes profiling interfaces */
|
static int probes_profile_seq_show(struct seq_file *m, void *v)
|
{
|
struct dyn_event *ev = v;
|
struct trace_uprobe *tu;
|
|
if (!is_trace_uprobe(ev))
|
return 0;
|
|
tu = to_trace_uprobe(ev);
|
seq_printf(m, " %s %-44s %15lu\n", tu->filename,
|
trace_probe_name(&tu->tp), tu->nhit);
|
return 0;
|
}
|
|
static const struct seq_operations profile_seq_op = {
|
.start = dyn_event_seq_start,
|
.next = dyn_event_seq_next,
|
.stop = dyn_event_seq_stop,
|
.show = probes_profile_seq_show
|
};
|
|
static int profile_open(struct inode *inode, struct file *file)
|
{
|
int ret;
|
|
ret = security_locked_down(LOCKDOWN_TRACEFS);
|
if (ret)
|
return ret;
|
|
return seq_open(file, &profile_seq_op);
|
}
|
|
static const struct file_operations uprobe_profile_ops = {
|
.owner = THIS_MODULE,
|
.open = profile_open,
|
.read = seq_read,
|
.llseek = seq_lseek,
|
.release = seq_release,
|
};
|
|
struct uprobe_cpu_buffer {
|
struct mutex mutex;
|
void *buf;
|
};
|
static struct uprobe_cpu_buffer __percpu *uprobe_cpu_buffer;
|
static int uprobe_buffer_refcnt;
|
|
static int uprobe_buffer_init(void)
|
{
|
int cpu, err_cpu;
|
|
uprobe_cpu_buffer = alloc_percpu(struct uprobe_cpu_buffer);
|
if (uprobe_cpu_buffer == NULL)
|
return -ENOMEM;
|
|
for_each_possible_cpu(cpu) {
|
struct page *p = alloc_pages_node(cpu_to_node(cpu),
|
GFP_KERNEL, 0);
|
if (p == NULL) {
|
err_cpu = cpu;
|
goto err;
|
}
|
per_cpu_ptr(uprobe_cpu_buffer, cpu)->buf = page_address(p);
|
mutex_init(&per_cpu_ptr(uprobe_cpu_buffer, cpu)->mutex);
|
}
|
|
return 0;
|
|
err:
|
for_each_possible_cpu(cpu) {
|
if (cpu == err_cpu)
|
break;
|
free_page((unsigned long)per_cpu_ptr(uprobe_cpu_buffer, cpu)->buf);
|
}
|
|
free_percpu(uprobe_cpu_buffer);
|
return -ENOMEM;
|
}
|
|
static int uprobe_buffer_enable(void)
|
{
|
int ret = 0;
|
|
BUG_ON(!mutex_is_locked(&event_mutex));
|
|
if (uprobe_buffer_refcnt++ == 0) {
|
ret = uprobe_buffer_init();
|
if (ret < 0)
|
uprobe_buffer_refcnt--;
|
}
|
|
return ret;
|
}
|
|
static void uprobe_buffer_disable(void)
|
{
|
int cpu;
|
|
BUG_ON(!mutex_is_locked(&event_mutex));
|
|
if (--uprobe_buffer_refcnt == 0) {
|
for_each_possible_cpu(cpu)
|
free_page((unsigned long)per_cpu_ptr(uprobe_cpu_buffer,
|
cpu)->buf);
|
|
free_percpu(uprobe_cpu_buffer);
|
uprobe_cpu_buffer = NULL;
|
}
|
}
|
|
static struct uprobe_cpu_buffer *uprobe_buffer_get(void)
|
{
|
struct uprobe_cpu_buffer *ucb;
|
int cpu;
|
|
cpu = raw_smp_processor_id();
|
ucb = per_cpu_ptr(uprobe_cpu_buffer, cpu);
|
|
/*
|
* Use per-cpu buffers for fastest access, but we might migrate
|
* so the mutex makes sure we have sole access to it.
|
*/
|
mutex_lock(&ucb->mutex);
|
|
return ucb;
|
}
|
|
static void uprobe_buffer_put(struct uprobe_cpu_buffer *ucb)
|
{
|
mutex_unlock(&ucb->mutex);
|
}
|
|
static void __uprobe_trace_func(struct trace_uprobe *tu,
|
unsigned long func, struct pt_regs *regs,
|
struct uprobe_cpu_buffer *ucb, int dsize,
|
struct trace_event_file *trace_file)
|
{
|
struct uprobe_trace_entry_head *entry;
|
struct trace_buffer *buffer;
|
struct ring_buffer_event *event;
|
void *data;
|
int size, esize;
|
struct trace_event_call *call = trace_probe_event_call(&tu->tp);
|
|
WARN_ON(call != trace_file->event_call);
|
|
if (WARN_ON_ONCE(tu->tp.size + dsize > PAGE_SIZE))
|
return;
|
|
if (trace_trigger_soft_disabled(trace_file))
|
return;
|
|
esize = SIZEOF_TRACE_ENTRY(is_ret_probe(tu));
|
size = esize + tu->tp.size + dsize;
|
event = trace_event_buffer_lock_reserve(&buffer, trace_file,
|
call->event.type, size, 0);
|
if (!event)
|
return;
|
|
entry = ring_buffer_event_data(event);
|
if (is_ret_probe(tu)) {
|
entry->vaddr[0] = func;
|
entry->vaddr[1] = instruction_pointer(regs);
|
data = DATAOF_TRACE_ENTRY(entry, true);
|
} else {
|
entry->vaddr[0] = instruction_pointer(regs);
|
data = DATAOF_TRACE_ENTRY(entry, false);
|
}
|
|
memcpy(data, ucb->buf, tu->tp.size + dsize);
|
|
event_trigger_unlock_commit(trace_file, buffer, event, entry, 0);
|
}
|
|
/* uprobe handler */
|
static int uprobe_trace_func(struct trace_uprobe *tu, struct pt_regs *regs,
|
struct uprobe_cpu_buffer *ucb, int dsize)
|
{
|
struct event_file_link *link;
|
|
if (is_ret_probe(tu))
|
return 0;
|
|
rcu_read_lock();
|
trace_probe_for_each_link_rcu(link, &tu->tp)
|
__uprobe_trace_func(tu, 0, regs, ucb, dsize, link->file);
|
rcu_read_unlock();
|
|
return 0;
|
}
|
|
static void uretprobe_trace_func(struct trace_uprobe *tu, unsigned long func,
|
struct pt_regs *regs,
|
struct uprobe_cpu_buffer *ucb, int dsize)
|
{
|
struct event_file_link *link;
|
|
rcu_read_lock();
|
trace_probe_for_each_link_rcu(link, &tu->tp)
|
__uprobe_trace_func(tu, func, regs, ucb, dsize, link->file);
|
rcu_read_unlock();
|
}
|
|
/* Event entry printers */
|
static enum print_line_t
|
print_uprobe_event(struct trace_iterator *iter, int flags, struct trace_event *event)
|
{
|
struct uprobe_trace_entry_head *entry;
|
struct trace_seq *s = &iter->seq;
|
struct trace_uprobe *tu;
|
u8 *data;
|
|
entry = (struct uprobe_trace_entry_head *)iter->ent;
|
tu = trace_uprobe_primary_from_call(
|
container_of(event, struct trace_event_call, event));
|
if (unlikely(!tu))
|
goto out;
|
|
if (is_ret_probe(tu)) {
|
trace_seq_printf(s, "%s: (0x%lx <- 0x%lx)",
|
trace_probe_name(&tu->tp),
|
entry->vaddr[1], entry->vaddr[0]);
|
data = DATAOF_TRACE_ENTRY(entry, true);
|
} else {
|
trace_seq_printf(s, "%s: (0x%lx)",
|
trace_probe_name(&tu->tp),
|
entry->vaddr[0]);
|
data = DATAOF_TRACE_ENTRY(entry, false);
|
}
|
|
if (print_probe_args(s, tu->tp.args, tu->tp.nr_args, data, entry) < 0)
|
goto out;
|
|
trace_seq_putc(s, '\n');
|
|
out:
|
return trace_handle_return(s);
|
}
|
|
typedef bool (*filter_func_t)(struct uprobe_consumer *self,
|
enum uprobe_filter_ctx ctx,
|
struct mm_struct *mm);
|
|
static int trace_uprobe_enable(struct trace_uprobe *tu, filter_func_t filter)
|
{
|
int ret;
|
|
tu->consumer.filter = filter;
|
tu->inode = d_real_inode(tu->path.dentry);
|
|
if (tu->ref_ctr_offset)
|
ret = uprobe_register_refctr(tu->inode, tu->offset,
|
tu->ref_ctr_offset, &tu->consumer);
|
else
|
ret = uprobe_register(tu->inode, tu->offset, &tu->consumer);
|
|
if (ret)
|
tu->inode = NULL;
|
|
return ret;
|
}
|
|
static void __probe_event_disable(struct trace_probe *tp)
|
{
|
struct trace_probe *pos;
|
struct trace_uprobe *tu;
|
|
tu = container_of(tp, struct trace_uprobe, tp);
|
WARN_ON(!uprobe_filter_is_empty(tu->tp.event->filter));
|
|
list_for_each_entry(pos, trace_probe_probe_list(tp), list) {
|
tu = container_of(pos, struct trace_uprobe, tp);
|
if (!tu->inode)
|
continue;
|
|
uprobe_unregister(tu->inode, tu->offset, &tu->consumer);
|
tu->inode = NULL;
|
}
|
}
|
|
static int probe_event_enable(struct trace_event_call *call,
|
struct trace_event_file *file, filter_func_t filter)
|
{
|
struct trace_probe *pos, *tp;
|
struct trace_uprobe *tu;
|
bool enabled;
|
int ret;
|
|
tp = trace_probe_primary_from_call(call);
|
if (WARN_ON_ONCE(!tp))
|
return -ENODEV;
|
enabled = trace_probe_is_enabled(tp);
|
|
/* This may also change "enabled" state */
|
if (file) {
|
if (trace_probe_test_flag(tp, TP_FLAG_PROFILE))
|
return -EINTR;
|
|
ret = trace_probe_add_file(tp, file);
|
if (ret < 0)
|
return ret;
|
} else {
|
if (trace_probe_test_flag(tp, TP_FLAG_TRACE))
|
return -EINTR;
|
|
trace_probe_set_flag(tp, TP_FLAG_PROFILE);
|
}
|
|
tu = container_of(tp, struct trace_uprobe, tp);
|
WARN_ON(!uprobe_filter_is_empty(tu->tp.event->filter));
|
|
if (enabled)
|
return 0;
|
|
ret = uprobe_buffer_enable();
|
if (ret)
|
goto err_flags;
|
|
list_for_each_entry(pos, trace_probe_probe_list(tp), list) {
|
tu = container_of(pos, struct trace_uprobe, tp);
|
ret = trace_uprobe_enable(tu, filter);
|
if (ret) {
|
__probe_event_disable(tp);
|
goto err_buffer;
|
}
|
}
|
|
return 0;
|
|
err_buffer:
|
uprobe_buffer_disable();
|
|
err_flags:
|
if (file)
|
trace_probe_remove_file(tp, file);
|
else
|
trace_probe_clear_flag(tp, TP_FLAG_PROFILE);
|
|
return ret;
|
}
|
|
static void probe_event_disable(struct trace_event_call *call,
|
struct trace_event_file *file)
|
{
|
struct trace_probe *tp;
|
|
tp = trace_probe_primary_from_call(call);
|
if (WARN_ON_ONCE(!tp))
|
return;
|
|
if (!trace_probe_is_enabled(tp))
|
return;
|
|
if (file) {
|
if (trace_probe_remove_file(tp, file) < 0)
|
return;
|
|
if (trace_probe_is_enabled(tp))
|
return;
|
} else
|
trace_probe_clear_flag(tp, TP_FLAG_PROFILE);
|
|
__probe_event_disable(tp);
|
uprobe_buffer_disable();
|
}
|
|
static int uprobe_event_define_fields(struct trace_event_call *event_call)
|
{
|
int ret, size;
|
struct uprobe_trace_entry_head field;
|
struct trace_uprobe *tu;
|
|
tu = trace_uprobe_primary_from_call(event_call);
|
if (unlikely(!tu))
|
return -ENODEV;
|
|
if (is_ret_probe(tu)) {
|
DEFINE_FIELD(unsigned long, vaddr[0], FIELD_STRING_FUNC, 0);
|
DEFINE_FIELD(unsigned long, vaddr[1], FIELD_STRING_RETIP, 0);
|
size = SIZEOF_TRACE_ENTRY(true);
|
} else {
|
DEFINE_FIELD(unsigned long, vaddr[0], FIELD_STRING_IP, 0);
|
size = SIZEOF_TRACE_ENTRY(false);
|
}
|
|
return traceprobe_define_arg_fields(event_call, size, &tu->tp);
|
}
|
|
#ifdef CONFIG_PERF_EVENTS
|
static bool
|
__uprobe_perf_filter(struct trace_uprobe_filter *filter, struct mm_struct *mm)
|
{
|
struct perf_event *event;
|
|
if (filter->nr_systemwide)
|
return true;
|
|
list_for_each_entry(event, &filter->perf_events, hw.tp_list) {
|
if (event->hw.target->mm == mm)
|
return true;
|
}
|
|
return false;
|
}
|
|
static inline bool
|
trace_uprobe_filter_event(struct trace_uprobe_filter *filter,
|
struct perf_event *event)
|
{
|
return __uprobe_perf_filter(filter, event->hw.target->mm);
|
}
|
|
static bool trace_uprobe_filter_remove(struct trace_uprobe_filter *filter,
|
struct perf_event *event)
|
{
|
bool done;
|
|
write_lock(&filter->rwlock);
|
if (event->hw.target) {
|
list_del(&event->hw.tp_list);
|
done = filter->nr_systemwide ||
|
(event->hw.target->flags & PF_EXITING) ||
|
trace_uprobe_filter_event(filter, event);
|
} else {
|
filter->nr_systemwide--;
|
done = filter->nr_systemwide;
|
}
|
write_unlock(&filter->rwlock);
|
|
return done;
|
}
|
|
/* This returns true if the filter always covers target mm */
|
static bool trace_uprobe_filter_add(struct trace_uprobe_filter *filter,
|
struct perf_event *event)
|
{
|
bool done;
|
|
write_lock(&filter->rwlock);
|
if (event->hw.target) {
|
/*
|
* event->parent != NULL means copy_process(), we can avoid
|
* uprobe_apply(). current->mm must be probed and we can rely
|
* on dup_mmap() which preserves the already installed bp's.
|
*
|
* attr.enable_on_exec means that exec/mmap will install the
|
* breakpoints we need.
|
*/
|
done = filter->nr_systemwide ||
|
event->parent || event->attr.enable_on_exec ||
|
trace_uprobe_filter_event(filter, event);
|
list_add(&event->hw.tp_list, &filter->perf_events);
|
} else {
|
done = filter->nr_systemwide;
|
filter->nr_systemwide++;
|
}
|
write_unlock(&filter->rwlock);
|
|
return done;
|
}
|
|
static int uprobe_perf_close(struct trace_event_call *call,
|
struct perf_event *event)
|
{
|
struct trace_probe *pos, *tp;
|
struct trace_uprobe *tu;
|
int ret = 0;
|
|
tp = trace_probe_primary_from_call(call);
|
if (WARN_ON_ONCE(!tp))
|
return -ENODEV;
|
|
tu = container_of(tp, struct trace_uprobe, tp);
|
if (trace_uprobe_filter_remove(tu->tp.event->filter, event))
|
return 0;
|
|
list_for_each_entry(pos, trace_probe_probe_list(tp), list) {
|
tu = container_of(pos, struct trace_uprobe, tp);
|
ret = uprobe_apply(tu->inode, tu->offset, &tu->consumer, false);
|
if (ret)
|
break;
|
}
|
|
return ret;
|
}
|
|
static int uprobe_perf_open(struct trace_event_call *call,
|
struct perf_event *event)
|
{
|
struct trace_probe *pos, *tp;
|
struct trace_uprobe *tu;
|
int err = 0;
|
|
tp = trace_probe_primary_from_call(call);
|
if (WARN_ON_ONCE(!tp))
|
return -ENODEV;
|
|
tu = container_of(tp, struct trace_uprobe, tp);
|
if (trace_uprobe_filter_add(tu->tp.event->filter, event))
|
return 0;
|
|
list_for_each_entry(pos, trace_probe_probe_list(tp), list) {
|
tu = container_of(pos, struct trace_uprobe, tp);
|
err = uprobe_apply(tu->inode, tu->offset, &tu->consumer, true);
|
if (err) {
|
uprobe_perf_close(call, event);
|
break;
|
}
|
}
|
|
return err;
|
}
|
|
static bool uprobe_perf_filter(struct uprobe_consumer *uc,
|
enum uprobe_filter_ctx ctx, struct mm_struct *mm)
|
{
|
struct trace_uprobe_filter *filter;
|
struct trace_uprobe *tu;
|
int ret;
|
|
tu = container_of(uc, struct trace_uprobe, consumer);
|
filter = tu->tp.event->filter;
|
|
read_lock(&filter->rwlock);
|
ret = __uprobe_perf_filter(filter, mm);
|
read_unlock(&filter->rwlock);
|
|
return ret;
|
}
|
|
static void __uprobe_perf_func(struct trace_uprobe *tu,
|
unsigned long func, struct pt_regs *regs,
|
struct uprobe_cpu_buffer *ucb, int dsize)
|
{
|
struct trace_event_call *call = trace_probe_event_call(&tu->tp);
|
struct uprobe_trace_entry_head *entry;
|
struct hlist_head *head;
|
void *data;
|
int size, esize;
|
int rctx;
|
|
if (bpf_prog_array_valid(call)) {
|
u32 ret;
|
|
preempt_disable();
|
ret = trace_call_bpf(call, regs);
|
preempt_enable();
|
if (!ret)
|
return;
|
}
|
|
esize = SIZEOF_TRACE_ENTRY(is_ret_probe(tu));
|
|
size = esize + tu->tp.size + dsize;
|
size = ALIGN(size + sizeof(u32), sizeof(u64)) - sizeof(u32);
|
if (WARN_ONCE(size > PERF_MAX_TRACE_SIZE, "profile buffer not large enough"))
|
return;
|
|
preempt_disable();
|
head = this_cpu_ptr(call->perf_events);
|
if (hlist_empty(head))
|
goto out;
|
|
entry = perf_trace_buf_alloc(size, NULL, &rctx);
|
if (!entry)
|
goto out;
|
|
if (is_ret_probe(tu)) {
|
entry->vaddr[0] = func;
|
entry->vaddr[1] = instruction_pointer(regs);
|
data = DATAOF_TRACE_ENTRY(entry, true);
|
} else {
|
entry->vaddr[0] = instruction_pointer(regs);
|
data = DATAOF_TRACE_ENTRY(entry, false);
|
}
|
|
memcpy(data, ucb->buf, tu->tp.size + dsize);
|
|
if (size - esize > tu->tp.size + dsize) {
|
int len = tu->tp.size + dsize;
|
|
memset(data + len, 0, size - esize - len);
|
}
|
|
perf_trace_buf_submit(entry, size, rctx, call->event.type, 1, regs,
|
head, NULL);
|
out:
|
preempt_enable();
|
}
|
|
/* uprobe profile handler */
|
static int uprobe_perf_func(struct trace_uprobe *tu, struct pt_regs *regs,
|
struct uprobe_cpu_buffer *ucb, int dsize)
|
{
|
if (!uprobe_perf_filter(&tu->consumer, 0, current->mm))
|
return UPROBE_HANDLER_REMOVE;
|
|
if (!is_ret_probe(tu))
|
__uprobe_perf_func(tu, 0, regs, ucb, dsize);
|
return 0;
|
}
|
|
static void uretprobe_perf_func(struct trace_uprobe *tu, unsigned long func,
|
struct pt_regs *regs,
|
struct uprobe_cpu_buffer *ucb, int dsize)
|
{
|
__uprobe_perf_func(tu, func, regs, ucb, dsize);
|
}
|
|
int bpf_get_uprobe_info(const struct perf_event *event, u32 *fd_type,
|
const char **filename, u64 *probe_offset,
|
bool perf_type_tracepoint)
|
{
|
const char *pevent = trace_event_name(event->tp_event);
|
const char *group = event->tp_event->class->system;
|
struct trace_uprobe *tu;
|
|
if (perf_type_tracepoint)
|
tu = find_probe_event(pevent, group);
|
else
|
tu = trace_uprobe_primary_from_call(event->tp_event);
|
if (!tu)
|
return -EINVAL;
|
|
*fd_type = is_ret_probe(tu) ? BPF_FD_TYPE_URETPROBE
|
: BPF_FD_TYPE_UPROBE;
|
*filename = tu->filename;
|
*probe_offset = tu->offset;
|
return 0;
|
}
|
#endif /* CONFIG_PERF_EVENTS */
|
|
static int
|
trace_uprobe_register(struct trace_event_call *event, enum trace_reg type,
|
void *data)
|
{
|
struct trace_event_file *file = data;
|
|
switch (type) {
|
case TRACE_REG_REGISTER:
|
return probe_event_enable(event, file, NULL);
|
|
case TRACE_REG_UNREGISTER:
|
probe_event_disable(event, file);
|
return 0;
|
|
#ifdef CONFIG_PERF_EVENTS
|
case TRACE_REG_PERF_REGISTER:
|
return probe_event_enable(event, NULL, uprobe_perf_filter);
|
|
case TRACE_REG_PERF_UNREGISTER:
|
probe_event_disable(event, NULL);
|
return 0;
|
|
case TRACE_REG_PERF_OPEN:
|
return uprobe_perf_open(event, data);
|
|
case TRACE_REG_PERF_CLOSE:
|
return uprobe_perf_close(event, data);
|
|
#endif
|
default:
|
return 0;
|
}
|
}
|
|
static int uprobe_dispatcher(struct uprobe_consumer *con, struct pt_regs *regs)
|
{
|
struct trace_uprobe *tu;
|
struct uprobe_dispatch_data udd;
|
struct uprobe_cpu_buffer *ucb;
|
int dsize, esize;
|
int ret = 0;
|
|
|
tu = container_of(con, struct trace_uprobe, consumer);
|
tu->nhit++;
|
|
udd.tu = tu;
|
udd.bp_addr = instruction_pointer(regs);
|
|
current->utask->vaddr = (unsigned long) &udd;
|
|
if (WARN_ON_ONCE(!uprobe_cpu_buffer))
|
return 0;
|
|
dsize = __get_data_size(&tu->tp, regs);
|
esize = SIZEOF_TRACE_ENTRY(is_ret_probe(tu));
|
|
ucb = uprobe_buffer_get();
|
store_trace_args(ucb->buf, &tu->tp, regs, esize, dsize);
|
|
if (trace_probe_test_flag(&tu->tp, TP_FLAG_TRACE))
|
ret |= uprobe_trace_func(tu, regs, ucb, dsize);
|
|
#ifdef CONFIG_PERF_EVENTS
|
if (trace_probe_test_flag(&tu->tp, TP_FLAG_PROFILE))
|
ret |= uprobe_perf_func(tu, regs, ucb, dsize);
|
#endif
|
uprobe_buffer_put(ucb);
|
return ret;
|
}
|
|
static int uretprobe_dispatcher(struct uprobe_consumer *con,
|
unsigned long func, struct pt_regs *regs)
|
{
|
struct trace_uprobe *tu;
|
struct uprobe_dispatch_data udd;
|
struct uprobe_cpu_buffer *ucb;
|
int dsize, esize;
|
|
tu = container_of(con, struct trace_uprobe, consumer);
|
|
udd.tu = tu;
|
udd.bp_addr = func;
|
|
current->utask->vaddr = (unsigned long) &udd;
|
|
if (WARN_ON_ONCE(!uprobe_cpu_buffer))
|
return 0;
|
|
dsize = __get_data_size(&tu->tp, regs);
|
esize = SIZEOF_TRACE_ENTRY(is_ret_probe(tu));
|
|
ucb = uprobe_buffer_get();
|
store_trace_args(ucb->buf, &tu->tp, regs, esize, dsize);
|
|
if (trace_probe_test_flag(&tu->tp, TP_FLAG_TRACE))
|
uretprobe_trace_func(tu, func, regs, ucb, dsize);
|
|
#ifdef CONFIG_PERF_EVENTS
|
if (trace_probe_test_flag(&tu->tp, TP_FLAG_PROFILE))
|
uretprobe_perf_func(tu, func, regs, ucb, dsize);
|
#endif
|
uprobe_buffer_put(ucb);
|
return 0;
|
}
|
|
static struct trace_event_functions uprobe_funcs = {
|
.trace = print_uprobe_event
|
};
|
|
static struct trace_event_fields uprobe_fields_array[] = {
|
{ .type = TRACE_FUNCTION_TYPE,
|
.define_fields = uprobe_event_define_fields },
|
{}
|
};
|
|
static inline void init_trace_event_call(struct trace_uprobe *tu)
|
{
|
struct trace_event_call *call = trace_probe_event_call(&tu->tp);
|
call->event.funcs = &uprobe_funcs;
|
call->class->fields_array = uprobe_fields_array;
|
|
call->flags = TRACE_EVENT_FL_UPROBE | TRACE_EVENT_FL_CAP_ANY;
|
call->class->reg = trace_uprobe_register;
|
}
|
|
static int register_uprobe_event(struct trace_uprobe *tu)
|
{
|
init_trace_event_call(tu);
|
|
return trace_probe_register_event_call(&tu->tp);
|
}
|
|
static int unregister_uprobe_event(struct trace_uprobe *tu)
|
{
|
return trace_probe_unregister_event_call(&tu->tp);
|
}
|
|
#ifdef CONFIG_PERF_EVENTS
|
struct trace_event_call *
|
create_local_trace_uprobe(char *name, unsigned long offs,
|
unsigned long ref_ctr_offset, bool is_return)
|
{
|
struct trace_uprobe *tu;
|
struct path path;
|
int ret;
|
|
ret = kern_path(name, LOOKUP_FOLLOW, &path);
|
if (ret)
|
return ERR_PTR(ret);
|
|
if (!d_is_reg(path.dentry)) {
|
path_put(&path);
|
return ERR_PTR(-EINVAL);
|
}
|
|
/*
|
* local trace_kprobes are not added to dyn_event, so they are never
|
* searched in find_trace_kprobe(). Therefore, there is no concern of
|
* duplicated name "DUMMY_EVENT" here.
|
*/
|
tu = alloc_trace_uprobe(UPROBE_EVENT_SYSTEM, "DUMMY_EVENT", 0,
|
is_return);
|
|
if (IS_ERR(tu)) {
|
pr_info("Failed to allocate trace_uprobe.(%d)\n",
|
(int)PTR_ERR(tu));
|
path_put(&path);
|
return ERR_CAST(tu);
|
}
|
|
tu->offset = offs;
|
tu->path = path;
|
tu->ref_ctr_offset = ref_ctr_offset;
|
tu->filename = kstrdup(name, GFP_KERNEL);
|
init_trace_event_call(tu);
|
|
if (traceprobe_set_print_fmt(&tu->tp, is_ret_probe(tu)) < 0) {
|
ret = -ENOMEM;
|
goto error;
|
}
|
|
return trace_probe_event_call(&tu->tp);
|
error:
|
free_trace_uprobe(tu);
|
return ERR_PTR(ret);
|
}
|
|
void destroy_local_trace_uprobe(struct trace_event_call *event_call)
|
{
|
struct trace_uprobe *tu;
|
|
tu = trace_uprobe_primary_from_call(event_call);
|
|
free_trace_uprobe(tu);
|
}
|
#endif /* CONFIG_PERF_EVENTS */
|
|
/* Make a trace interface for controling probe points */
|
static __init int init_uprobe_trace(void)
|
{
|
int ret;
|
|
ret = dyn_event_register(&trace_uprobe_ops);
|
if (ret)
|
return ret;
|
|
ret = tracing_init_dentry();
|
if (ret)
|
return 0;
|
|
trace_create_file("uprobe_events", 0644, NULL,
|
NULL, &uprobe_events_ops);
|
/* Profile interface */
|
trace_create_file("uprobe_profile", 0444, NULL,
|
NULL, &uprobe_profile_ops);
|
return 0;
|
}
|
|
fs_initcall(init_uprobe_trace);
|
