From: Filipe Manana <fdmanana@suse.com>
Date: Wed, 7 Jul 2021 11:23:45 +0000 (+0100)
Subject: btrfs: zoned: fix wrong mutex unlock on failure to allocate log root tree
X-Git-Tag: v5.12.19~264
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=7b1ca403621f2977828f967525884f57ed17730f;p=thirdparty%2Fkernel%2Fstable.git

btrfs: zoned: fix wrong mutex unlock on failure to allocate log root tree

commit ea32af47f00a046a1f953370514d6d946efe0152 upstream.

When syncing the log, if we fail to allocate the root node for the log
root tree:

1) We are unlocking fs_info->tree_log_mutex, but at this point we have
   not yet locked this mutex;

2) We have locked fs_info->tree_root->log_mutex, but we end up not
   unlocking it;

So fix this by unlocking fs_info->tree_root->log_mutex instead of
fs_info->tree_log_mutex.

Fixes: e75f9fd194090e ("btrfs: zoned: move log tree node allocation out of log_root_tree->log_mutex")
CC: stable@vger.kernel.org # 5.13+
Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@wdc.com>
Signed-off-by: Filipe Manana <fdmanana@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index f4b0aecdaac72..fae59c8f86405 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -3173,7 +3173,7 @@ int btrfs_sync_log(struct btrfs_trans_handle *trans,
 		if (!log_root_tree->node) {
 			ret = btrfs_alloc_log_tree_node(trans, log_root_tree);
 			if (ret) {
-				mutex_unlock(&fs_info->tree_log_mutex);
+				mutex_unlock(&fs_info->tree_root->log_mutex);
 				goto out;
 			}
 		}