From: Josef Bacik Date: Wed, 18 Dec 2019 22:20:29 +0000 (-0500) Subject: btrfs: do not delete mismatched root refs X-Git-Tag: v3.16.83~127 X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=81ead8db7b30e6c60f542d66a782d77b35ae8b77;p=thirdparty%2Fkernel%2Fstable.git 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. Signed-off-by: Josef Bacik Reviewed-by: David Sterba Signed-off-by: David Sterba Signed-off-by: Ben Hutchings --- diff --git a/fs/btrfs/root-tree.c b/fs/btrfs/root-tree.c index 360a728a639fe..9bdcae8336ffb 100644 --- a/fs/btrfs/root-tree.c +++ b/fs/btrfs/root-tree.c @@ -373,11 +373,13 @@ 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);