From: Josef Bacik josef@toxicpanda.com
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
--- fs/btrfs/root-tree.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-)
--- a/fs/btrfs/root-tree.c +++ b/fs/btrfs/root-tree.c @@ -370,11 +370,13 @@ 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);