btrfs: do not delete mismatched root refs

commit 423a716cd7be16fb08690760691befe3be97d3fc upstream.

btrfs_del_root_ref() will simply WARN_ON() if the ref doesn't match in
any way, and then continue to delete the reference.  This shouldn't
happen, we have these values because there's more to the reference than
the original root and the sub root.  If any of these checks fail, return
-ENOENT.

CC: stable@vger.kernel.org # 4.4+
Signed-off-by: Josef Bacik <josef@toxicpanda.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
This commit is contained in:
Josef Bacik 2019-12-18 17:20:29 -05:00 committed by Greg Kroah-Hartman
parent d5e34783c8
commit 4c281ce51c
1 changed files with 6 additions and 4 deletions

View File

@ -376,11 +376,13 @@ again:
leaf = path->nodes[0];
ref = btrfs_item_ptr(leaf, path->slots[0],
struct btrfs_root_ref);
WARN_ON(btrfs_root_ref_dirid(leaf, ref) != dirid);
WARN_ON(btrfs_root_ref_name_len(leaf, ref) != name_len);
ptr = (unsigned long)(ref + 1);
WARN_ON(memcmp_extent_buffer(leaf, name, ptr, name_len));
if ((btrfs_root_ref_dirid(leaf, ref) != dirid) ||
(btrfs_root_ref_name_len(leaf, ref) != name_len) ||
memcmp_extent_buffer(leaf, name, ptr, name_len)) {
err = -ENOENT;
goto out;
}
*sequence = btrfs_root_ref_sequence(leaf, ref);
ret = btrfs_del_item(trans, tree_root, path);