btrfs: do not delete mismatched root refs

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>
This commit is contained in:
Josef Bacik 2019-12-18 17:20:29 -05:00 committed by David Sterba
parent d49d3287e7
commit 423a716cd7

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);