]> git.karo-electronics.de Git - linux-beck.git/commitdiff
usermodehelper: check subprocess_info->path != NULL
authorOleg Nesterov <oleg@redhat.com>
Thu, 16 May 2013 15:43:55 +0000 (17:43 +0200)
committerLinus Torvalds <torvalds@linux-foundation.org>
Thu, 16 May 2013 19:01:11 +0000 (12:01 -0700)
argv_split(empty_or_all_spaces) happily succeeds, it simply returns
argc == 0 and argv[0] == NULL. Change call_usermodehelper_exec() to
check sub_info->path != NULL to avoid the crash.

This is the minimal fix, todo:

 - perhaps we should change argv_split() to return NULL or change the
   callers.

 - kill or justify ->path[0] check

 - narrow the scope of helper_lock()

Signed-off-by: Oleg Nesterov <oleg@redhat.com>
Acked-By: Lucas De Marchi <lucas.demarchi@intel.com>
Cc: stable@vger.kernel.org
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
kernel/kmod.c

index 1296e72e4161be305e37606f6024db1a84ff73a3..8241906c4b61a0887304f6524516563707d1a876 100644 (file)
@@ -569,6 +569,11 @@ int call_usermodehelper_exec(struct subprocess_info *sub_info, int wait)
        int retval = 0;
 
        helper_lock();
+       if (!sub_info->path) {
+               retval = -EINVAL;
+               goto out;
+       }
+
        if (sub_info->path[0] == '\0')
                goto out;