From 102a0743326a03cd1a1202ceda21e175b7d3575c Mon Sep 17 00:00:00 2001
From: hc <hc@nodka.com>
Date: Tue, 20 Feb 2024 01:20:52 +0000
Subject: [PATCH] add new system file
---
kernel/fs/binfmt_flat.c | 136 ++++++++++++++++++++++++++++++++-------------
1 files changed, 96 insertions(+), 40 deletions(-)
diff --git a/kernel/fs/binfmt_flat.c b/kernel/fs/binfmt_flat.c
index e4b59e7..69f4db0 100644
--- a/kernel/fs/binfmt_flat.c
+++ b/kernel/fs/binfmt_flat.c
@@ -42,6 +42,11 @@
#include <asm/unaligned.h>
#include <asm/cacheflush.h>
#include <asm/page.h>
+#include <asm/flat.h>
+
+#ifndef flat_get_relocate_addr
+#define flat_get_relocate_addr(rel) (rel)
+#endif
/****************************************************************************/
@@ -62,6 +67,12 @@
#define RELOC_FAILED 0xff00ff01 /* Relocation incorrect somewhere */
#define UNLOADED_LIB 0x7ff000ff /* Placeholder for unused library */
+
+#ifdef CONFIG_BINFMT_SHARED_FLAT
+#define MAX_SHARED_LIBS (4)
+#else
+#define MAX_SHARED_LIBS (1)
+#endif
struct lib_info {
struct {
@@ -120,41 +131,47 @@
sp -= bprm->envc + 1;
sp -= bprm->argc + 1;
- sp -= flat_argvp_envp_on_stack() ? 2 : 0;
+ if (IS_ENABLED(CONFIG_BINFMT_FLAT_ARGVP_ENVP_ON_STACK))
+ sp -= 2; /* argvp + envp */
sp -= 1; /* &argc */
current->mm->start_stack = (unsigned long)sp & -FLAT_STACK_ALIGN;
sp = (unsigned long __user *)current->mm->start_stack;
- __put_user(bprm->argc, sp++);
- if (flat_argvp_envp_on_stack()) {
+ if (put_user(bprm->argc, sp++))
+ return -EFAULT;
+ if (IS_ENABLED(CONFIG_BINFMT_FLAT_ARGVP_ENVP_ON_STACK)) {
unsigned long argv, envp;
argv = (unsigned long)(sp + 2);
envp = (unsigned long)(sp + 2 + bprm->argc + 1);
- __put_user(argv, sp++);
- __put_user(envp, sp++);
+ if (put_user(argv, sp++) || put_user(envp, sp++))
+ return -EFAULT;
}
current->mm->arg_start = (unsigned long)p;
for (i = bprm->argc; i > 0; i--) {
- __put_user((unsigned long)p, sp++);
+ if (put_user((unsigned long)p, sp++))
+ return -EFAULT;
len = strnlen_user(p, MAX_ARG_STRLEN);
if (!len || len > MAX_ARG_STRLEN)
return -EINVAL;
p += len;
}
- __put_user(0, sp++);
+ if (put_user(0, sp++))
+ return -EFAULT;
current->mm->arg_end = (unsigned long)p;
current->mm->env_start = (unsigned long) p;
for (i = bprm->envc; i > 0; i--) {
- __put_user((unsigned long)p, sp++);
+ if (put_user((unsigned long)p, sp++))
+ return -EFAULT;
len = strnlen_user(p, MAX_ARG_STRLEN);
if (!len || len > MAX_ARG_STRLEN)
return -EINVAL;
p += len;
}
- __put_user(0, sp++);
+ if (put_user(0, sp++))
+ return -EFAULT;
current->mm->env_end = (unsigned long)p;
return 0;
@@ -345,7 +362,7 @@
start_code = p->lib_list[id].start_code;
text_len = p->lib_list[id].text_len;
- if (!flat_reloc_valid(r, start_brk - start_data + text_len)) {
+ if (r > start_brk - start_data + text_len) {
pr_err("reloc outside program 0x%lx (0 - 0x%lx/0x%lx)",
r, start_brk-start_data+text_len, text_len);
goto failed;
@@ -368,6 +385,7 @@
/****************************************************************************/
+#ifdef CONFIG_BINFMT_FLAT_OLD
static void old_reloc(unsigned long rl)
{
static const char *segment[] = { "TEXT", "DATA", "BSS", "*UNKNOWN*" };
@@ -405,8 +423,33 @@
pr_debug("Relocation became %lx\n", val);
}
+#endif /* CONFIG_BINFMT_FLAT_OLD */
/****************************************************************************/
+
+static inline u32 __user *skip_got_header(u32 __user *rp)
+{
+ if (IS_ENABLED(CONFIG_RISCV)) {
+ /*
+ * RISC-V has a 16 byte GOT PLT header for elf64-riscv
+ * and 8 byte GOT PLT header for elf32-riscv.
+ * Skip the whole GOT PLT header, since it is reserved
+ * for the dynamic linker (ld.so).
+ */
+ u32 rp_val0, rp_val1;
+
+ if (get_user(rp_val0, rp))
+ return rp;
+ if (get_user(rp_val1, rp + 1))
+ return rp;
+
+ if (rp_val0 == 0xffffffff && rp_val1 == 0xffffffff)
+ rp += 4;
+ else if (rp_val0 == 0xffffffff)
+ rp += 2;
+ }
+ return rp;
+}
static int load_flat_file(struct linux_binprm *bprm,
struct lib_info *libinfo, int id, unsigned long *extra_stack)
@@ -415,8 +458,8 @@
unsigned long textpos, datapos, realdatastart;
u32 text_len, data_len, bss_len, stack_len, full_data, flags;
unsigned long len, memp, memp_size, extra, rlim;
- u32 __user *reloc, *rp;
- struct inode *inode;
+ __be32 __user *reloc;
+ u32 __user *rp;
int i, rev, relocs;
loff_t fpos;
unsigned long start_code, end_code;
@@ -424,7 +467,6 @@
int ret;
hdr = ((struct flat_hdr *) bprm->buf); /* exec-header */
- inode = file_inode(bprm->file);
text_len = ntohl(hdr->data_start);
data_len = ntohl(hdr->data_end) - ntohl(hdr->data_start);
@@ -454,6 +496,7 @@
if (flags & FLAT_FLAG_KTRACE)
pr_info("Loading file: %s\n", bprm->filename);
+#ifdef CONFIG_BINFMT_FLAT_OLD
if (rev != FLAT_VERSION && rev != OLD_FLAT_VERSION) {
pr_err("bad flat file version 0x%x (supported 0x%lx and 0x%lx)\n",
rev, FLAT_VERSION, OLD_FLAT_VERSION);
@@ -470,6 +513,23 @@
}
/*
+ * fix up the flags for the older format, there were all kinds
+ * of endian hacks, this only works for the simple cases
+ */
+ if (rev == OLD_FLAT_VERSION &&
+ (flags || IS_ENABLED(CONFIG_BINFMT_FLAT_OLD_ALWAYS_RAM)))
+ flags = FLAT_FLAG_RAM;
+
+#else /* CONFIG_BINFMT_FLAT_OLD */
+ if (rev != FLAT_VERSION) {
+ pr_err("bad flat file version 0x%x (supported 0x%lx)\n",
+ rev, FLAT_VERSION);
+ ret = -ENOEXEC;
+ goto err;
+ }
+#endif /* !CONFIG_BINFMT_FLAT_OLD */
+
+ /*
* Make sure the header params are sane.
* 28 bits (256 MB) is way more than reasonable in this case.
* If some top bits are set we have probable binary corruption.
@@ -479,13 +539,6 @@
ret = -ENOEXEC;
goto err;
}
-
- /*
- * fix up the flags for the older format, there were all kinds
- * of endian hacks, this only works for the simple cases
- */
- if (rev == OLD_FLAT_VERSION && flat_old_ram_flag(flags))
- flags = FLAT_FLAG_RAM;
#ifndef CONFIG_BINFMT_ZFLAT
if (flags & (FLAT_FLAG_GZIP|FLAT_FLAG_GZDATA)) {
@@ -510,7 +563,7 @@
/* Flush all traces of the currently running executable */
if (id == 0) {
- ret = flush_old_exec(bprm);
+ ret = begin_new_exec(bprm);
if (ret)
goto err;
@@ -587,7 +640,7 @@
goto err;
}
- reloc = (u32 __user *)
+ reloc = (__be32 __user *)
(datapos + (ntohl(hdr->reloc_start) - text_len));
memp = realdatastart;
memp_size = len;
@@ -612,7 +665,7 @@
MAX_SHARED_LIBS * sizeof(u32),
FLAT_DATA_ALIGN);
- reloc = (u32 __user *)
+ reloc = (__be32 __user *)
(datapos + (ntohl(hdr->reloc_start) - text_len));
memp = textpos;
memp_size = len;
@@ -745,7 +798,8 @@
* image.
*/
if (flags & FLAT_FLAG_GOTPIC) {
- for (rp = (u32 __user *)datapos; ; rp++) {
+ rp = skip_got_header((u32 __user *) datapos);
+ for (; ; rp++) {
u32 addr, rp_val;
if (get_user(rp_val, rp))
return -EFAULT;
@@ -775,20 +829,18 @@
* __start to address 4 so that is okay).
*/
if (rev > OLD_FLAT_VERSION) {
- u32 __maybe_unused persistent = 0;
for (i = 0; i < relocs; i++) {
u32 addr, relval;
+ __be32 tmp;
/*
* Get the address of the pointer to be
* relocated (of course, the address has to be
* relocated first).
*/
- if (get_user(relval, reloc + i))
+ if (get_user(tmp, reloc + i))
return -EFAULT;
- relval = ntohl(relval);
- if (flat_set_persistent(relval, &persistent))
- continue;
+ relval = ntohl(tmp);
addr = flat_get_relocate_addr(relval);
rp = (u32 __user *)calc_reloc(addr, libinfo, id, 1);
if (rp == (u32 __user *)RELOC_FAILED) {
@@ -797,8 +849,7 @@
}
/* Get the pointer's value. */
- ret = flat_get_addr_from_rp(rp, relval, flags,
- &addr, &persistent);
+ ret = flat_get_addr_from_rp(rp, relval, flags, &addr);
if (unlikely(ret))
goto err;
@@ -807,8 +858,13 @@
* Do the relocation. PIC relocs in the data section are
* already in target order
*/
- if ((flags & FLAT_FLAG_GOTPIC) == 0)
- addr = ntohl(addr);
+ if ((flags & FLAT_FLAG_GOTPIC) == 0) {
+ /*
+ * Meh, the same value can have a different
+ * byte order based on a flag..
+ */
+ addr = ntohl((__force __be32)addr);
+ }
addr = calc_reloc(addr, libinfo, id, 0);
if (addr == RELOC_FAILED) {
ret = -ENOEXEC;
@@ -821,17 +877,18 @@
goto err;
}
}
+#ifdef CONFIG_BINFMT_FLAT_OLD
} else {
for (i = 0; i < relocs; i++) {
- u32 relval;
+ __be32 relval;
if (get_user(relval, reloc + i))
return -EFAULT;
- relval = ntohl(relval);
- old_reloc(relval);
+ old_reloc(ntohl(relval));
}
+#endif /* CONFIG_BINFMT_FLAT_OLD */
}
- flush_icache_range(start_code, end_code);
+ flush_icache_user_range(start_code, end_code);
/* zero the BSS, BRK and stack areas */
if (clear_user((void __user *)(datapos + data_len), bss_len +
@@ -940,8 +997,6 @@
}
}
- install_exec_creds(bprm);
-
set_binfmt(&flat_format);
#ifdef CONFIG_MMU
@@ -975,7 +1030,8 @@
unsigned long __user *sp;
current->mm->start_stack -= sizeof(unsigned long);
sp = (unsigned long __user *)current->mm->start_stack;
- __put_user(start_addr, sp);
+ if (put_user(start_addr, sp))
+ return -EFAULT;
start_addr = libinfo.lib_list[i].entry;
}
}
--
Gitblit v1.6.2