ext4: Fix fs corruption when make_indexed_dir() fails

When make_indexed_dir() fails (e.g. because of ENOSPC) after it has
allocated block for index tree root, we did not properly mark all
changed buffers dirty.  This lead to only some of these buffers being
written out and thus effectively corrupting the directory.

Fix the issue by marking all changed data dirty even in the error
failure case.

Signed-off-by: Jan Kara <jack@suse.cz>
Signed-off-by: "Theodore Ts'o" <tytso@mit.edu>
diff --git a/fs/ext4/namei.c b/fs/ext4/namei.c
index 67fd0b0..cadf04b 100644
--- a/fs/ext4/namei.c
+++ b/fs/ext4/namei.c
@@ -1414,9 +1414,19 @@
 	frame->bh = bh;
 	bh = bh2;
 	de = do_split(handle,dir, &bh, frame, &hinfo, &retval);
-	dx_release (frames);
-	if (!(de))
+	if (!de) {
+		/*
+		 * Even if the block split failed, we have to properly write
+		 * out all the changes we did so far. Otherwise we can end up
+		 * with corrupted filesystem.
+		 */
+		ext4_mark_inode_dirty(handle, dir);
+		ext4_handle_dirty_metadata(handle, dir, frame->bh);
+		ext4_handle_dirty_metadata(handle, dir, bh);
+		dx_release(frames);
 		return retval;
+	}
+	dx_release(frames);
 
 	retval = add_dirent_to_buf(handle, dentry, inode, de, bh);
 	brelse(bh);