fs/block_dev: fix potential NULL ptr deref in freeze_bdev()

[linux-2.6-microblaze.git] / fs / block_dev.c

diff --git a/fs/block_dev.c b/fs/block_dev.c
index e17bdbd..08ae993 100644 (file)
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -249,7 +249,8 @@ struct super_block *freeze_bdev(struct block_device *bdev)
                 * thaw_bdev drops it.
                 */
                sb = get_super(bdev);
-               drop_super(sb);
+               if (sb)
+                       drop_super(sb);
                mutex_unlock(&bdev->bd_fsfreeze_mutex);
                return sb;
        }