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Diffstat (limited to 'kernel/module.c')
-rw-r--r--kernel/module.c224
1 files changed, 125 insertions, 99 deletions
diff --git a/kernel/module.c b/kernel/module.c
index 60cdd0459eac..fb11e2a88233 100644
--- a/kernel/module.c
+++ b/kernel/module.c
@@ -115,6 +115,8 @@ struct load_info {
unsigned long len;
Elf_Shdr *sechdrs;
char *secstrings, *args, *strtab;
+ unsigned long *strmap;
+ unsigned long symoffs, stroffs;
struct {
unsigned int sym, str, mod, vers, info, pcpu;
} index;
@@ -402,7 +404,8 @@ static int percpu_modalloc(struct module *mod,
mod->percpu = __alloc_reserved_percpu(size, align);
if (!mod->percpu) {
printk(KERN_WARNING
- "Could not allocate %lu bytes percpu data\n", size);
+ "%s: Could not allocate %lu bytes percpu data\n",
+ mod->name, size);
return -ENOMEM;
}
mod->percpu_size = size;
@@ -2032,10 +2035,7 @@ static unsigned long layout_symtab(struct module *mod,
return symoffs;
}
-static void add_kallsyms(struct module *mod, struct load_info *info,
- unsigned long symoffs,
- unsigned long stroffs,
- unsigned long *strmap)
+static void add_kallsyms(struct module *mod, struct load_info *info)
{
unsigned int i, ndst;
const Elf_Sym *src;
@@ -2052,21 +2052,22 @@ static void add_kallsyms(struct module *mod, struct load_info *info,
for (i = 0; i < mod->num_symtab; i++)
mod->symtab[i].st_info = elf_type(&mod->symtab[i], info);
- mod->core_symtab = dst = mod->module_core + symoffs;
+ mod->core_symtab = dst = mod->module_core + info->symoffs;
src = mod->symtab;
*dst = *src;
for (ndst = i = 1; i < mod->num_symtab; ++i, ++src) {
if (!is_core_symbol(src, info->sechdrs, info->hdr->e_shnum))
continue;
dst[ndst] = *src;
- dst[ndst].st_name = bitmap_weight(strmap, dst[ndst].st_name);
+ dst[ndst].st_name = bitmap_weight(info->strmap,
+ dst[ndst].st_name);
++ndst;
}
mod->core_num_syms = ndst;
- mod->core_strtab = s = mod->module_core + stroffs;
+ mod->core_strtab = s = mod->module_core + info->stroffs;
for (*s = 0, i = 1; i < info->sechdrs[info->index.str].sh_size; ++i)
- if (test_bit(i, strmap))
+ if (test_bit(i, info->strmap))
*++s = mod->strtab[i];
}
#else
@@ -2082,10 +2083,7 @@ static inline unsigned long layout_symtab(struct module *mod,
return 0;
}
-static void add_kallsyms(struct module *mod, struct load_info *info,
- unsigned long symoffs,
- unsigned long stroffs,
- unsigned long *strmap)
+static void add_kallsyms(struct module *mod, struct load_info *info)
{
}
#endif /* CONFIG_KALLSYMS */
@@ -2150,8 +2148,10 @@ static inline void kmemleak_load_module(struct module *mod, Elf_Ehdr *hdr,
}
#endif
-/* Sets info->hdr and info->len. */
-static int copy_and_check(struct load_info *info, const void __user *umod, unsigned long len)
+/* Sets info->hdr, info->len and info->args. */
+static int copy_and_check(struct load_info *info,
+ const void __user *umod, unsigned long len,
+ const char __user *uargs)
{
int err;
Elf_Ehdr *hdr;
@@ -2183,6 +2183,14 @@ static int copy_and_check(struct load_info *info, const void __user *umod, unsig
err = -ENOEXEC;
goto free_hdr;
}
+
+ /* Now copy in args */
+ info->args = strndup_user(uargs, ~0UL >> 1);
+ if (IS_ERR(info->args)) {
+ err = PTR_ERR(info->args);
+ goto free_hdr;
+ }
+
info->hdr = hdr;
info->len = len;
return 0;
@@ -2192,6 +2200,12 @@ free_hdr:
return err;
}
+static void free_copy(struct load_info *info)
+{
+ kfree(info->args);
+ vfree(info->hdr);
+}
+
static int rewrite_section_headers(struct load_info *info)
{
unsigned int i;
@@ -2385,9 +2399,9 @@ static void find_module_sections(struct module *mod, Elf_Ehdr *hdr,
mod->name);
}
-static struct module *move_module(struct module *mod,
- Elf_Ehdr *hdr, Elf_Shdr *sechdrs,
- const char *secstrings, unsigned modindex)
+static int move_module(struct module *mod,
+ Elf_Ehdr *hdr, Elf_Shdr *sechdrs,
+ const char *secstrings, unsigned modindex)
{
int i;
void *ptr;
@@ -2401,7 +2415,7 @@ static struct module *move_module(struct module *mod,
*/
kmemleak_not_leak(ptr);
if (!ptr)
- return ERR_PTR(-ENOMEM);
+ return -ENOMEM;
memset(ptr, 0, mod->core_size);
mod->module_core = ptr;
@@ -2416,7 +2430,7 @@ static struct module *move_module(struct module *mod,
kmemleak_ignore(ptr);
if (!ptr && mod->init_size) {
module_free(mod, mod->module_core);
- return ERR_PTR(-ENOMEM);
+ return -ENOMEM;
}
memset(ptr, 0, mod->init_size);
mod->module_init = ptr;
@@ -2443,10 +2457,8 @@ static struct module *move_module(struct module *mod,
DEBUGP("\t0x%lx %s\n",
sechdrs[i].sh_addr, secstrings + sechdrs[i].sh_name);
}
- /* Module has been moved. */
- mod = (void *)sechdrs[modindex].sh_addr;
- kmemleak_load_module(mod, hdr, sechdrs, secstrings);
- return mod;
+
+ return 0;
}
static int check_module_license_and_versions(struct module *mod,
@@ -2503,87 +2515,107 @@ static void flush_module_icache(const struct module *mod)
set_fs(old_fs);
}
-/* Allocate and load the module: note that size of section 0 is always
- zero, and we rely on this for optional sections. */
-static noinline struct module *load_module(void __user *umod,
- unsigned long len,
- const char __user *uargs)
+static struct module *layout_and_allocate(struct load_info *info)
{
- struct load_info info = { NULL, };
+ /* Module within temporary copy. */
struct module *mod;
- long err;
- unsigned long symoffs, stroffs, *strmap;
- void __percpu *percpu;
- struct _ddebug *debug = NULL;
- unsigned int num_debug = 0;
+ int err;
- DEBUGP("load_module: umod=%p, len=%lu, uargs=%p\n",
- umod, len, uargs);
+ mod = setup_load_info(info);
+ if (IS_ERR(mod))
+ return mod;
- err = copy_and_check(&info, umod, len);
+ err = check_modinfo(mod, info->sechdrs, info->index.info, info->index.vers);
if (err)
return ERR_PTR(err);
- mod = setup_load_info(&info);
- if (IS_ERR(mod)) {
- err = PTR_ERR(mod);
- goto free_hdr;
- }
-
- err = check_modinfo(mod, info.sechdrs, info.index.info, info.index.vers);
- if (err)
- goto free_hdr;
-
- /* Now copy in args */
- info.args = strndup_user(uargs, ~0UL >> 1);
- if (IS_ERR(info.args)) {
- err = PTR_ERR(info.args);
- goto free_hdr;
- }
-
- strmap = kzalloc(BITS_TO_LONGS(info.sechdrs[info.index.str].sh_size)
- * sizeof(long), GFP_KERNEL);
- if (!strmap) {
- err = -ENOMEM;
- goto free_mod;
- }
-
- mod->state = MODULE_STATE_COMING;
-
/* Allow arches to frob section contents and sizes. */
- err = module_frob_arch_sections(info.hdr, info.sechdrs, info.secstrings, mod);
+ err = module_frob_arch_sections(info->hdr, info->sechdrs, info->secstrings, mod);
if (err < 0)
- goto free_mod;
+ goto free_args;
- if (info.index.pcpu) {
+ if (info->index.pcpu) {
/* We have a special allocation for this section. */
- err = percpu_modalloc(mod, info.sechdrs[info.index.pcpu].sh_size,
- info.sechdrs[info.index.pcpu].sh_addralign);
+ err = percpu_modalloc(mod, info->sechdrs[info->index.pcpu].sh_size,
+ info->sechdrs[info->index.pcpu].sh_addralign);
if (err)
- goto free_mod;
- info.sechdrs[info.index.pcpu].sh_flags &= ~(unsigned long)SHF_ALLOC;
+ goto free_args;
+ info->sechdrs[info->index.pcpu].sh_flags &= ~(unsigned long)SHF_ALLOC;
}
- /* Keep this around for failure path. */
- percpu = mod_percpu(mod);
/* Determine total sizes, and put offsets in sh_entsize. For now
this is done generically; there doesn't appear to be any
special cases for the architectures. */
- layout_sections(mod, info.hdr, info.sechdrs, info.secstrings);
- symoffs = layout_symtab(mod, info.sechdrs, info.index.sym, info.index.str, info.hdr,
- info.secstrings, &stroffs, strmap);
+ layout_sections(mod, info->hdr, info->sechdrs, info->secstrings);
+
+ info->strmap = kzalloc(BITS_TO_LONGS(info->sechdrs[info->index.str].sh_size)
+ * sizeof(long), GFP_KERNEL);
+ if (!info->strmap) {
+ err = -ENOMEM;
+ goto free_percpu;
+ }
+ info->symoffs = layout_symtab(mod, info->sechdrs, info->index.sym, info->index.str, info->hdr,
+ info->secstrings, &info->stroffs, info->strmap);
/* Allocate and move to the final place */
- mod = move_module(mod, info.hdr, info.sechdrs, info.secstrings, info.index.mod);
+ err = move_module(mod, info->hdr, info->sechdrs, info->secstrings, info->index.mod);
+ if (err)
+ goto free_strmap;
+
+ /* Module has been copied to its final place now: return it. */
+ mod = (void *)info->sechdrs[info->index.mod].sh_addr;
+ kmemleak_load_module(mod, info->hdr, info->sechdrs, info->secstrings);
+ return mod;
+
+free_strmap:
+ kfree(info->strmap);
+free_percpu:
+ percpu_modfree(mod);
+free_args:
+ kfree(info->args);
+ return ERR_PTR(err);
+}
+
+/* mod is no longer valid after this! */
+static void module_deallocate(struct module *mod, struct load_info *info)
+{
+ kfree(info->strmap);
+ percpu_modfree(mod);
+ module_free(mod, mod->module_init);
+ module_free(mod, mod->module_core);
+}
+
+/* Allocate and load the module: note that size of section 0 is always
+ zero, and we rely on this for optional sections. */
+static noinline struct module *load_module(void __user *umod,
+ unsigned long len,
+ const char __user *uargs)
+{
+ struct load_info info = { NULL, };
+ struct module *mod;
+ long err;
+ struct _ddebug *debug = NULL;
+ unsigned int num_debug = 0;
+
+ DEBUGP("load_module: umod=%p, len=%lu, uargs=%p\n",
+ umod, len, uargs);
+
+ /* Copy in the blobs from userspace, check they are vaguely sane. */
+ err = copy_and_check(&info, umod, len, uargs);
+ if (err)
+ return ERR_PTR(err);
+
+ /* Figure out module layout, and allocate all the memory. */
+ mod = layout_and_allocate(&info);
if (IS_ERR(mod)) {
err = PTR_ERR(mod);
- goto free_percpu;
+ goto free_copy;
}
/* Now we've moved module, initialize linked lists, etc. */
err = module_unload_init(mod);
if (err)
- goto free_init;
+ goto free_module;
/* Now we've got everything in the final locations, we can
* find optional sections. */
@@ -2600,11 +2632,11 @@ static noinline struct module *load_module(void __user *umod,
err = simplify_symbols(info.sechdrs, info.index.sym, info.strtab, info.index.vers, info.index.pcpu,
mod);
if (err < 0)
- goto cleanup;
+ goto free_modinfo;
err = apply_relocations(mod, info.hdr, info.sechdrs, info.index.sym, info.index.str);
if (err < 0)
- goto cleanup;
+ goto free_modinfo;
/* Set up and sort exception table */
mod->extable = section_objs(info.hdr, info.sechdrs, info.secstrings, "__ex_table",
@@ -2615,9 +2647,7 @@ static noinline struct module *load_module(void __user *umod,
percpu_modcopy(mod, (void *)info.sechdrs[info.index.pcpu].sh_addr,
info.sechdrs[info.index.pcpu].sh_size);
- add_kallsyms(mod, &info, symoffs, stroffs, strmap);
- kfree(strmap);
- strmap = NULL;
+ add_kallsyms(mod, &info);
if (!mod->taints)
debug = section_objs(info.hdr, info.sechdrs, info.secstrings, "__verbose",
@@ -2625,12 +2655,14 @@ static noinline struct module *load_module(void __user *umod,
err = module_finalize(info.hdr, info.sechdrs, mod);
if (err < 0)
- goto cleanup;
+ goto free_modinfo;
flush_module_icache(mod);
mod->args = info.args;
+ mod->state = MODULE_STATE_COMING;
+
/* Now sew it into the lists so we can get lockdep and oops
* info during argument parsing. Noone should access us, since
* strong_try_module_get() will fail.
@@ -2666,8 +2698,9 @@ static noinline struct module *load_module(void __user *umod,
add_sect_attrs(mod, info.hdr->e_shnum, info.secstrings, info.sechdrs);
add_notes_attrs(mod, info.hdr->e_shnum, info.secstrings, info.sechdrs);
- /* Get rid of temporary copy */
- vfree(info.hdr);
+ /* Get rid of temporary copy and strmap. */
+ kfree(info.strmap);
+ free_copy(&info);
trace_module_load(mod);
@@ -2684,21 +2717,14 @@ static noinline struct module *load_module(void __user *umod,
mutex_unlock(&module_mutex);
synchronize_sched();
module_arch_cleanup(mod);
- cleanup:
+ free_modinfo:
free_modinfo(mod);
free_unload:
module_unload_free(mod);
- free_init:
- module_free(mod, mod->module_init);
- module_free(mod, mod->module_core);
- /* mod will be freed with core. Don't access it beyond this line! */
- free_percpu:
- free_percpu(percpu);
- free_mod:
- kfree(info.args);
- kfree(strmap);
- free_hdr:
- vfree(info.hdr);
+ free_module:
+ module_deallocate(mod, &info);
+ free_copy:
+ free_copy(&info);
return ERR_PTR(err);
}