[PATCH] net: sched: qfq: dont intepret cls results when asked to drop

From: Ma Ke
Date: Fri Sep 15 2023 - 06:53:22 EST


If asked to drop a packet via TC_ACT_SHOT it is unsafe to
assume that res.class contains a valid pointer.

Signed-off-by: Ma Ke <make_ruc2021@xxxxxxx>
---
net/sched/sch_qfq.c | 2 ++
1 file changed, 2 insertions(+)

diff --git a/net/sched/sch_qfq.c b/net/sched/sch_qfq.c
index 546c10adcacd..20d52dc484b6 100644
--- a/net/sched/sch_qfq.c
+++ b/net/sched/sch_qfq.c
@@ -695,6 +695,8 @@ static struct qfq_class *qfq_classify(struct sk_buff *skb, struct Qdisc *sch,
*qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
fl = rcu_dereference_bh(q->filter_list);
result = tcf_classify(skb, NULL, fl, &res, false);
+ if (result == TC_ACT_SHOT)
+ return NULL;
if (result >= 0) {
#ifdef CONFIG_NET_CLS_ACT
switch (result) {
--
2.37.2