[PATCH] ensure NULL deref can't possibly happen in is_exported()
Jesper Juhl [Sun, 25 Jun 2006 12:47:09 +0000 (05:47 -0700)]
If CONFIG_KALLSYMS is defined and if it should happen that is_exported() is
given a NULL 'mod' and lookup_symbol(name, __start___ksymtab,
__stop___ksymtab) returns 0, then we'll end up dereferencing a NULL
pointer.

Signed-off-by: Jesper Juhl <jesper.juhl@gmail.com>
Cc: Rusty Russell <rusty@rustcorp.com.au>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

kernel/module.c

index bbe0486..d75275d 100644 (file)
@@ -1326,7 +1326,7 @@ int is_exported(const char *name, const struct module *mod)
        if (!mod && lookup_symbol(name, __start___ksymtab, __stop___ksymtab))
                return 1;
        else
-               if (lookup_symbol(name, mod->syms, mod->syms + mod->num_syms))
+               if (mod && lookup_symbol(name, mod->syms, mod->syms + mod->num_syms))
                        return 1;
                else
                        return 0;