!886 net: sched: fix NULL pointer dereference in mq_attach

Merge Pull Request from: @ci-robot 
 
PR sync from:  Zhengchao Shao <shaozhengchao@huawei.com>
 https://mailweb.openeuler.org/hyperkitty/list/kernel@openeuler.org/thread/XWHRWDMB4P3YRCQBLQMFWCV4DDLKNDHE/ 
 
 
Link:https://gitee.com/openeuler/kernel/pulls/886 

Reviewed-by: Jialin Zhang <zhangjialin11@huawei.com> 
Signed-off-by: Jialin Zhang <zhangjialin11@huawei.com> 

net/sched/sch_api.c

@@ -1590,6 +1590,10 @@ static int tc_modify_qdisc(struct sk_buff *skb, struct nlmsghdr *n,
 					NL_SET_ERR_MSG(extack, "Qdisc parent/child loop detected");
 					return -ELOOP;
 				}
+				if (clid == TC_H_INGRESS) {
+					NL_SET_ERR_MSG(extack, "Ingress cannot graft directly");
+					return -EINVAL;
+				}
 				qdisc_refcount_inc(q);
 				goto graft;
 			} else {