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/kallsyms.c | 30 +++++++++++++++--------------- 1 file changed, 15 insertions(+), 15 deletions(-) (limited to 'kernel/kallsyms.c') diff --git a/kernel/kallsyms.c b/kernel/kallsyms.c index d086c91d44e..f1ea6f66ac6 100644 --- a/kernel/kallsyms.c +++ b/kernel/kallsyms.c @@ -301,25 +301,20 @@ void __print_symbol(const char *fmt, unsigned long address) struct kallsym_iter { loff_t pos; - struct module *owner; unsigned long value; unsigned int nameoff; /* If iterating in core kernel symbols */ char type; char name[KSYM_NAME_LEN+1]; + char module_name[MODULE_NAME_LEN + 1]; + int exported; }; static int get_ksymbol_mod(struct kallsym_iter *iter) { - iter->owner = module_get_kallsym(iter->pos - kallsyms_num_syms, - &iter->value, &iter->type, - iter->name); - if (iter->owner == NULL) + if (module_get_kallsym(iter->pos - kallsyms_num_syms, &iter->value, + &iter->type, iter->name, iter->module_name, + &iter->exported) < 0) return 0; - - /* Label it "global" if it is exported, "local" if not exported. */ - iter->type = is_exported(iter->name, iter->owner) - ? toupper(iter->type) : tolower(iter->type); - return 1; } @@ -328,7 +323,7 @@ static unsigned long get_ksymbol_core(struct kallsym_iter *iter) { unsigned off = iter->nameoff; - iter->owner = NULL; + iter->module_name[0] = '\0'; iter->value = kallsyms_addresses[iter->pos]; iter->type = kallsyms_get_symbol_type(off); @@ -392,12 +387,17 @@ static int s_show(struct seq_file *m, void *p) if (!iter->name[0]) return 0; - if (iter->owner) + if (iter->module_name[0]) { + char type; + + /* Label it "global" if it is exported, + * "local" if not exported. */ + type = iter->exported ? toupper(iter->type) : + tolower(iter->type); seq_printf(m, "%0*lx %c %s\t[%s]\n", (int)(2*sizeof(void*)), - iter->value, iter->type, iter->name, - module_name(iter->owner)); - else + iter->value, type, iter->name, iter->module_name); + } else seq_printf(m, "%0*lx %c %s\n", (int)(2*sizeof(void*)), iter->value, iter->type, iter->name); -- cgit v1.2.3