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 <adobriyan@sw.ru>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Adrian Bunk <bunk@stusta.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/include/linux/module.h b/include/linux/module.h
index 7999302..58d5a10 100644
--- a/include/linux/module.h
+++ b/include/linux/module.h
@@ -370,16 +370,14 @@
struct module *__module_text_address(unsigned long addr);
int is_module_address(unsigned long addr);
-/* Returns module and fills in value, defined and namebuf, or NULL if
+/* Returns 0 and fills in value, defined and namebuf, or -ERANGE if
symnum out of range. */
-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);
/* Look for this name: can be of form module:name. */
unsigned long module_kallsyms_lookup_name(const char *name);
-int is_exported(const char *name, const struct module *mod);
-
extern void __module_put_and_exit(struct module *mod, long code)
__attribute__((noreturn));
#define module_put_and_exit(code) __module_put_and_exit(THIS_MODULE, code);
@@ -527,11 +525,11 @@
return NULL;
}
-static inline struct module *module_get_kallsym(unsigned int symnum,
- unsigned long *value,
- char *type, char *name)
+static inline int module_get_kallsym(unsigned int symnum, unsigned long *value,
+ char *type, char *name,
+ char *module_name, int *exported)
{
- return NULL;
+ return -ERANGE;
}
static inline unsigned long module_kallsyms_lookup_name(const char *name)
@@ -539,11 +537,6 @@
return 0;
}
-static inline int is_exported(const char *name, const struct module *mod)
-{
- return 0;
-}
-
static inline int register_module_notifier(struct notifier_block * nb)
{
/* no events will happen anyway, so this can always succeed */