From: Robbie Ko robbieko@synology.com
commit 6ff06729c22ec0b7498d900d79cc88cfb8aceaeb upstream.
Ordered ops are started twice in sync file, once outside of inode mutex and once inside, taking the dio semaphore. There was one error path missing the semaphore unlock.
Fixes: aab15e8ec2576 ("Btrfs: fix rare chances for data loss when doing a fast fsync") CC: stable@vger.kernel.org # 4.19+ Signed-off-by: Robbie Ko robbieko@synology.com Reviewed-by: Filipe Manana fdmanana@suse.com [ add changelog ] Signed-off-by: David Sterba dsterba@suse.com Signed-off-by: Greg Kroah-Hartman gregkh@linuxfoundation.org --- fs/btrfs/file.c | 1 + 1 file changed, 1 insertion(+)
diff --git a/fs/btrfs/file.c b/fs/btrfs/file.c index 1e3a600..dc18418 100644 --- a/fs/btrfs/file.c +++ b/fs/btrfs/file.c @@ -2137,6 +2137,7 @@ int btrfs_sync_file(struct file *file, loff_t start, loff_t end, int datasync) */ ret = start_ordered_ops(inode, start, end); if (ret) { + up_write(&BTRFS_I(inode)->dio_sem); inode_unlock(inode); goto out; }