From ea07890a680273b25127129fb555aac0d9324bea Mon Sep 17 00:00:00 2001 From: Alexey Dobriyan Date: Tue, 8 May 2007 00:28:39 -0700 Subject: Fix race between rmmod and cat /proc/kallsyms module_get_kallsym() leaks "struct module *" outside of module_mutex which is no-no, because module can dissapear right after mutex unlock. Copy all needed information from inside module_mutex into caller-supplied space. [bunk@stusta.de: is_exported() can now become static] Signed-off-by: Alexey Dobriyan Cc: Rusty Russell Signed-off-by: Adrian Bunk Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/module.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) (limited to 'kernel/module.c') diff --git a/kernel/module.c b/kernel/module.c index 43a529a1fa48..5ee65994a3bc 100644 --- a/kernel/module.c +++ b/kernel/module.c @@ -1472,7 +1472,7 @@ static void setup_modinfo(struct module *mod, Elf_Shdr *sechdrs, } #ifdef CONFIG_KALLSYMS -int is_exported(const char *name, const struct module *mod) +static int is_exported(const char *name, const struct module *mod) { if (!mod && lookup_symbol(name, __start___ksymtab, __stop___ksymtab)) return 1; @@ -2124,8 +2124,8 @@ const char *module_address_lookup(unsigned long addr, return NULL; } -struct module *module_get_kallsym(unsigned int symnum, unsigned long *value, - char *type, char *name) +int module_get_kallsym(unsigned int symnum, unsigned long *value, char *type, + char *name, char *module_name, int *exported) { struct module *mod; @@ -2136,13 +2136,15 @@ struct module *module_get_kallsym(unsigned int symnum, unsigned long *value, *type = mod->symtab[symnum].st_info; strlcpy(name, mod->strtab + mod->symtab[symnum].st_name, KSYM_NAME_LEN + 1); + strlcpy(module_name, mod->name, MODULE_NAME_LEN + 1); + *exported = is_exported(name, mod); mutex_unlock(&module_mutex); - return mod; + return 0; } symnum -= mod->num_symtab; } mutex_unlock(&module_mutex); - return NULL; + return -ERANGE; } static unsigned long mod_find_symname(struct module *mod, const char *name) -- cgit v1.2.3