btrfs: Check qgroup level in kernel qgroup assign.

[cascardo/linux.git] / fs / btrfs / qgroup.c

diff --git a/fs/btrfs/qgroup.c b/fs/btrfs/qgroup.c
index 464d1e2..4fb9610 100644 (file)
--- a/fs/btrfs/qgroup.c
+++ b/fs/btrfs/qgroup.c
@@ -1009,6 +1009,10 @@ int btrfs_add_qgroup_relation(struct btrfs_trans_handle *trans,
        struct btrfs_qgroup_list *list;
        int ret = 0;
 
+       /* Check the level of src and dst first */
+       if (btrfs_qgroup_level(src) >= btrfs_qgroup_level(dst))
+               return -EINVAL;
+
        mutex_lock(&fs_info->qgroup_ioctl_lock);
        quota_root = fs_info->quota_root;
        if (!quota_root) {