btrfs: fix the length of reserved qgroup to free

The dealloc flag may be cleared and the extent won't reach the disk in
cow_file_range when errors path. The reserved qgroup space is freed in
commit 30479f31d44d ("btrfs: fix qgroup reserve leaks in
cow_file_range"). However, the length of untouched region to free needs
to be adjusted with the correct remaining region size.

Fixes: 30479f31d44d ("btrfs: fix qgroup reserve leaks in cow_file_range")
CC: stable@vger.kernel.org # 6.11+
Reviewed-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: Boris Burkov <boris@bur.io>
Signed-off-by: Haisu Wang <haisuwang@tencent.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

diff --git a/fs/btrfs/inode.c b/fs/btrfs/inode.c
index c6d257fb40afa957f0197995326f07dbc931928f..a97dfc72a80a112bd512190f29cc7ea7e7d86f7e 100644 (file)
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -1618,7 +1618,7 @@ out_unlock:
                clear_bits |= EXTENT_CLEAR_DATA_RESV;
                extent_clear_unlock_delalloc(inode, start, end, locked_folio,
                                             &cached, clear_bits, page_ops);
-               btrfs_qgroup_free_data(inode, NULL, start, cur_alloc_size, NULL);
+               btrfs_qgroup_free_data(inode, NULL, start, end - start + 1, NULL);
        }
        return ret;
 }