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-rw-r--r--linux-user/elfload.c235
1 files changed, 170 insertions, 65 deletions
diff --git a/linux-user/elfload.c b/linux-user/elfload.c
index 547053c27a..5cea39d172 100644
--- a/linux-user/elfload.c
+++ b/linux-user/elfload.c
@@ -1231,6 +1231,14 @@ static inline void init_thread(struct target_pt_regs *regs,
#define ELF_HWCAP 0
#endif
+#ifndef STACK_GROWS_DOWN
+#define STACK_GROWS_DOWN 1
+#endif
+
+#ifndef STACK_ALIGNMENT
+#define STACK_ALIGNMENT 16
+#endif
+
#ifdef TARGET_ABI32
#undef ELF_CLASS
#define ELF_CLASS ELFCLASS32
@@ -1374,45 +1382,78 @@ static abi_ulong copy_elf_strings(int argc, char **argv, char *scratch,
abi_ulong p, abi_ulong stack_limit)
{
char *tmp;
- int len, offset;
+ int len, i;
abi_ulong top = p;
if (!p) {
return 0; /* bullet-proofing */
}
- offset = ((p - 1) % TARGET_PAGE_SIZE) + 1;
+ if (STACK_GROWS_DOWN) {
+ int offset = ((p - 1) % TARGET_PAGE_SIZE) + 1;
+ for (i = argc - 1; i >= 0; --i) {
+ tmp = argv[i];
+ if (!tmp) {
+ fprintf(stderr, "VFS: argc is wrong");
+ exit(-1);
+ }
+ len = strlen(tmp) + 1;
+ tmp += len;
- while (argc-- > 0) {
- tmp = argv[argc];
- if (!tmp) {
- fprintf(stderr, "VFS: argc is wrong");
- exit(-1);
+ if (len > (p - stack_limit)) {
+ return 0;
+ }
+ while (len) {
+ int bytes_to_copy = (len > offset) ? offset : len;
+ tmp -= bytes_to_copy;
+ p -= bytes_to_copy;
+ offset -= bytes_to_copy;
+ len -= bytes_to_copy;
+
+ memcpy_fromfs(scratch + offset, tmp, bytes_to_copy);
+
+ if (offset == 0) {
+ memcpy_to_target(p, scratch, top - p);
+ top = p;
+ offset = TARGET_PAGE_SIZE;
+ }
+ }
}
- len = strlen(tmp) + 1;
- tmp += len;
-
- if (len > (p - stack_limit)) {
- return 0;
+ if (p != top) {
+ memcpy_to_target(p, scratch + offset, top - p);
}
- while (len) {
- int bytes_to_copy = (len > offset) ? offset : len;
- tmp -= bytes_to_copy;
- p -= bytes_to_copy;
- offset -= bytes_to_copy;
- len -= bytes_to_copy;
-
- memcpy_fromfs(scratch + offset, tmp, bytes_to_copy);
-
- if (offset == 0) {
- memcpy_to_target(p, scratch, top - p);
- top = p;
- offset = TARGET_PAGE_SIZE;
+ } else {
+ int remaining = TARGET_PAGE_SIZE - (p % TARGET_PAGE_SIZE);
+ for (i = 0; i < argc; ++i) {
+ tmp = argv[i];
+ if (!tmp) {
+ fprintf(stderr, "VFS: argc is wrong");
+ exit(-1);
+ }
+ len = strlen(tmp) + 1;
+ if (len > (stack_limit - p)) {
+ return 0;
+ }
+ while (len) {
+ int bytes_to_copy = (len > remaining) ? remaining : len;
+
+ memcpy_fromfs(scratch + (p - top), tmp, bytes_to_copy);
+
+ tmp += bytes_to_copy;
+ remaining -= bytes_to_copy;
+ p += bytes_to_copy;
+ len -= bytes_to_copy;
+
+ if (remaining == 0) {
+ memcpy_to_target(top, scratch, p - top);
+ top = p;
+ remaining = TARGET_PAGE_SIZE;
+ }
}
}
- }
- if (offset) {
- memcpy_to_target(p, scratch + offset, top - p);
+ if (p != top) {
+ memcpy_to_target(top, scratch, p - top);
+ }
}
return p;
@@ -1447,11 +1488,15 @@ static abi_ulong setup_arg_pages(struct linux_binprm *bprm,
}
/* We reserve one extra page at the top of the stack as guard. */
- target_mprotect(error, guard, PROT_NONE);
-
- info->stack_limit = error + guard;
-
- return info->stack_limit + size - sizeof(void *);
+ if (STACK_GROWS_DOWN) {
+ target_mprotect(error, guard, PROT_NONE);
+ info->stack_limit = error + guard;
+ return info->stack_limit + size - sizeof(void *);
+ } else {
+ target_mprotect(error + size, guard, PROT_NONE);
+ info->stack_limit = error + size;
+ return error;
+ }
}
/* Map and zero the bss. We need to explicitly zero any fractional pages
@@ -1529,7 +1574,7 @@ static abi_ulong create_elf_tables(abi_ulong p, int argc, int envc,
struct image_info *interp_info)
{
abi_ulong sp;
- abi_ulong sp_auxv;
+ abi_ulong u_argc, u_argv, u_envp, u_auxv;
int size;
int i;
abi_ulong u_rand_bytes;
@@ -1558,10 +1603,25 @@ static abi_ulong create_elf_tables(abi_ulong p, int argc, int envc,
k_platform = ELF_PLATFORM;
if (k_platform) {
size_t len = strlen(k_platform) + 1;
- sp -= (len + n - 1) & ~(n - 1);
- u_platform = sp;
- /* FIXME - check return value of memcpy_to_target() for failure */
- memcpy_to_target(sp, k_platform, len);
+ if (STACK_GROWS_DOWN) {
+ sp -= (len + n - 1) & ~(n - 1);
+ u_platform = sp;
+ /* FIXME - check return value of memcpy_to_target() for failure */
+ memcpy_to_target(sp, k_platform, len);
+ } else {
+ memcpy_to_target(sp, k_platform, len);
+ u_platform = sp;
+ sp += len + 1;
+ }
+ }
+
+ /* Provide 16 byte alignment for the PRNG, and basic alignment for
+ * the argv and envp pointers.
+ */
+ if (STACK_GROWS_DOWN) {
+ sp = QEMU_ALIGN_DOWN(sp, 16);
+ } else {
+ sp = QEMU_ALIGN_UP(sp, 16);
}
/*
@@ -1571,15 +1631,17 @@ static abi_ulong create_elf_tables(abi_ulong p, int argc, int envc,
for (i = 0; i < 16; i++) {
k_rand_bytes[i] = rand();
}
- sp -= 16;
- u_rand_bytes = sp;
- /* FIXME - check return value of memcpy_to_target() for failure */
- memcpy_to_target(sp, k_rand_bytes, 16);
+ if (STACK_GROWS_DOWN) {
+ sp -= 16;
+ u_rand_bytes = sp;
+ /* FIXME - check return value of memcpy_to_target() for failure */
+ memcpy_to_target(sp, k_rand_bytes, 16);
+ } else {
+ memcpy_to_target(sp, k_rand_bytes, 16);
+ u_rand_bytes = sp;
+ sp += 16;
+ }
- /*
- * Force 16 byte _final_ alignment here for generality.
- */
- sp = sp &~ (abi_ulong)15;
size = (DLINFO_ITEMS + 1) * 2;
if (k_platform)
size += 2;
@@ -1592,20 +1654,31 @@ static abi_ulong create_elf_tables(abi_ulong p, int argc, int envc,
size += envc + argc + 2;
size += 1; /* argc itself */
size *= n;
- if (size & 15)
- sp -= 16 - (size & 15);
+
+ /* Allocate space and finalize stack alignment for entry now. */
+ if (STACK_GROWS_DOWN) {
+ u_argc = QEMU_ALIGN_DOWN(sp - size, STACK_ALIGNMENT);
+ sp = u_argc;
+ } else {
+ u_argc = sp;
+ sp = QEMU_ALIGN_UP(sp + size, STACK_ALIGNMENT);
+ }
+
+ u_argv = u_argc + n;
+ u_envp = u_argv + (argc + 1) * n;
+ u_auxv = u_envp + (envc + 1) * n;
+ info->saved_auxv = u_auxv;
+ info->arg_start = u_argv;
+ info->arg_end = u_argv + argc * n;
/* This is correct because Linux defines
* elf_addr_t as Elf32_Off / Elf64_Off
*/
#define NEW_AUX_ENT(id, val) do { \
- sp -= n; put_user_ual(val, sp); \
- sp -= n; put_user_ual(id, sp); \
+ put_user_ual(id, u_auxv); u_auxv += n; \
+ put_user_ual(val, u_auxv); u_auxv += n; \
} while(0)
- sp_auxv = sp;
- NEW_AUX_ENT (AT_NULL, 0);
-
/* There must be exactly DLINFO_ITEMS entries here. */
NEW_AUX_ENT(AT_PHDR, (abi_ulong)(info->load_addr + exec->e_phoff));
NEW_AUX_ENT(AT_PHENT, (abi_ulong)(sizeof (struct elf_phdr)));
@@ -1626,8 +1699,9 @@ static abi_ulong create_elf_tables(abi_ulong p, int argc, int envc,
NEW_AUX_ENT(AT_HWCAP2, (abi_ulong) ELF_HWCAP2);
#endif
- if (k_platform)
+ if (u_platform) {
NEW_AUX_ENT(AT_PLATFORM, u_platform);
+ }
#ifdef ARCH_DLINFO
/*
* ARCH_DLINFO must come last so platform specific code can enforce
@@ -1635,14 +1709,29 @@ static abi_ulong create_elf_tables(abi_ulong p, int argc, int envc,
*/
ARCH_DLINFO;
#endif
+ NEW_AUX_ENT (AT_NULL, 0);
#undef NEW_AUX_ENT
- info->saved_auxv = sp;
- info->auxv_len = sp_auxv - sp;
+ info->auxv_len = u_argv - info->saved_auxv;
+
+ put_user_ual(argc, u_argc);
+
+ p = info->arg_strings;
+ for (i = 0; i < argc; ++i) {
+ put_user_ual(p, u_argv);
+ u_argv += n;
+ p += target_strlen(p) + 1;
+ }
+ put_user_ual(0, u_argv);
+
+ p = info->env_strings;
+ for (i = 0; i < envc; ++i) {
+ put_user_ual(p, u_envp);
+ u_envp += n;
+ p += target_strlen(p) + 1;
+ }
+ put_user_ual(0, u_envp);
- sp = loader_build_argptr(envc, argc, sp, p, 0);
- /* Check the right amount of stack was allocated for auxvec, envp & argv. */
- assert(sp_auxv - sp == size);
return sp;
}
@@ -2213,12 +2302,28 @@ int load_elf_binary(struct linux_binprm *bprm, struct image_info *info)
bprm->p = setup_arg_pages(bprm, info);
scratch = g_new0(char, TARGET_PAGE_SIZE);
- bprm->p = copy_elf_strings(1, &bprm->filename, scratch,
- bprm->p, info->stack_limit);
- bprm->p = copy_elf_strings(bprm->envc, bprm->envp, scratch,
- bprm->p, info->stack_limit);
- bprm->p = copy_elf_strings(bprm->argc, bprm->argv, scratch,
- bprm->p, info->stack_limit);
+ if (STACK_GROWS_DOWN) {
+ bprm->p = copy_elf_strings(1, &bprm->filename, scratch,
+ bprm->p, info->stack_limit);
+ info->file_string = bprm->p;
+ bprm->p = copy_elf_strings(bprm->envc, bprm->envp, scratch,
+ bprm->p, info->stack_limit);
+ info->env_strings = bprm->p;
+ bprm->p = copy_elf_strings(bprm->argc, bprm->argv, scratch,
+ bprm->p, info->stack_limit);
+ info->arg_strings = bprm->p;
+ } else {
+ info->arg_strings = bprm->p;
+ bprm->p = copy_elf_strings(bprm->argc, bprm->argv, scratch,
+ bprm->p, info->stack_limit);
+ info->env_strings = bprm->p;
+ bprm->p = copy_elf_strings(bprm->envc, bprm->envp, scratch,
+ bprm->p, info->stack_limit);
+ info->file_string = bprm->p;
+ bprm->p = copy_elf_strings(1, &bprm->filename, scratch,
+ bprm->p, info->stack_limit);
+ }
+
g_free(scratch);
if (!bprm->p) {
generated by cgit v1.2.3 (git 2.26.2) at 2024-12-28 16:59:47 +0000