btrfs: fix silent failure when deleting root reference

commit 47bf225a8d2cccb15f7e8d4a1ed9b757dd86afd7 upstream.

At btrfs_del_root_ref(), if btrfs_search_slot() returns an error, we end
up returning from the function with a value of 0 (success). This happens
because the function returns the value stored in the variable 'err',
which is 0, while the error value we got from btrfs_search_slot() is
stored in the 'ret' variable.

So fix it by setting 'err' with the error value.

Fixes: 8289ed9f93bef2 ("btrfs: replace the BUG_ON in btrfs_del_root_ref with proper error handling")
CC: stable@vger.kernel.org # 5.16+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: Filipe Manana <fdmanana@suse.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>

diff --git a/fs/btrfs/root-tree.c b/fs/btrfs/root-tree.c
index 1fa0e5e2e3505e85f7fc2da0a65a520c553e6f47..9328d87d96888bd7a1f78ff57ee5e7ced835f28c 100644 (file)
--- a/fs/btrfs/root-tree.c
+++ b/fs/btrfs/root-tree.c
@@ -351,9 +351,10 @@ int btrfs_del_root_ref(struct btrfs_trans_handle *trans, u64 root_id,
        key.offset = ref_id;
 again:
        ret = btrfs_search_slot(trans, tree_root, &key, path, -1, 1);
-       if (ret < 0)
+       if (ret < 0) {
+               err = ret;
                goto out;
-       if (ret == 0) {
+       } else if (ret == 0) {
                leaf = path->nodes[0];
                ref = btrfs_item_ptr(leaf, path->slots[0],
                                     struct btrfs_root_ref);