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

From: Ma Ke
Date: Fri Sep 15 2023 - 10:28:49 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_htb.c | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/net/sched/sch_htb.c b/net/sched/sch_htb.c
index 0d947414e616..7b2e5037b713 100644
--- a/net/sched/sch_htb.c
+++ b/net/sched/sch_htb.c
@@ -243,6 +243,8 @@ static struct htb_class *htb_classify(struct sk_buff *skb, struct Qdisc *sch,

*qerr = NET_XMIT_SUCCESS | __NET_XMIT_BYPASS;
while (tcf && (result = tcf_classify(skb, NULL, tcf, &res, false)) >= 0) {
+ if (result == TC_ACT_SHOT)
+ return NULL;
#ifdef CONFIG_NET_CLS_ACT
switch (result) {
case TC_ACT_QUEUED:
@@ -250,8 +252,6 @@ static struct htb_class *htb_classify(struct sk_buff *skb, struct Qdisc *sch,
case TC_ACT_TRAP:
*qerr = NET_XMIT_SUCCESS | __NET_XMIT_STOLEN;
fallthrough;
- case TC_ACT_SHOT:
- return NULL;
}
#endif
cl = (void *)res.class;
--
2.37.2