[PATCH] affs: possible null pointer dereference in affs_rename()

If affs_bread() fails, the exit path calls mark_buffer_dirty_inode() with a
NULL argument.

Coverity CID: 312.

Signed-off-by: Florin Malita <fmalita@gmail.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

fs/affs/namei.c

@@ -416,10 +416,9 @@ affs_rename(struct inode *old_dir, struct dentry *old_dentry,
 			return retval;
 	}
 
-	retval = -EIO;
 	bh = affs_bread(sb, old_dentry->d_inode->i_ino);
 	if (!bh)
-		goto done;
+		return -EIO;
 
 	/* Remove header from its parent directory. */
 	affs_lock_dir(old_dir);