diff --git a/[refs] b/[refs]
index 341cf0847fa6..a1e26bdc0f28 100644
--- a/[refs]
+++ b/[refs]
@@ -1,2 +1,2 @@
 ---
-refs/heads/master: 58400fce5ac5939aadac8ce682edc192c6172f80
+refs/heads/master: b7fef4f593007d52ba7fe4427e099bd71c63c521
diff --git a/trunk/fs/btrfs/qgroup.c b/trunk/fs/btrfs/qgroup.c
index 49c4e6398f18..0932b839550c 100644
--- a/trunk/fs/btrfs/qgroup.c
+++ b/trunk/fs/btrfs/qgroup.c
@@ -954,6 +954,8 @@ int btrfs_add_qgroup_relation(struct btrfs_trans_handle *trans,
 			      struct btrfs_fs_info *fs_info, u64 src, u64 dst)
 {
 	struct btrfs_root *quota_root;
+	struct btrfs_qgroup *parent;
+	struct btrfs_qgroup *member;
 	int ret = 0;
 
 	mutex_lock(&fs_info->qgroup_ioctl_lock);
@@ -962,6 +964,12 @@ int btrfs_add_qgroup_relation(struct btrfs_trans_handle *trans,
 		ret = -EINVAL;
 		goto out;
 	}
+	member = find_qgroup_rb(fs_info, src);
+	parent = find_qgroup_rb(fs_info, dst);
+	if (!member || !parent) {
+		ret = -EINVAL;
+		goto out;
+	}
 
 	ret = add_qgroup_relation_item(trans, quota_root, src, dst);
 	if (ret)