From d09c548dbf3b31cb07bba562e0f452edfa01efe3 Mon Sep 17 00:00:00 2001 From: Hangbin Liu Date: Mon, 9 Aug 2021 15:04:55 +0800 Subject: [PATCH] net: sched: act_mirred: Reset ct info when mirror/redirect skb When mirror/redirect a skb to a different port, the ct info should be reset for reclassification. Or the pkts will match unexpected rules. For example, with following topology and commands: ----------- | veth0 -+------- | veth1 -+------- | ------------ tc qdisc add dev veth0 clsact # The same with "action mirred egress mirror dev veth1" or "action mirred ingress redirect dev veth1" tc filter add dev veth0 egress chain 1 protocol ip flower ct_state +trk action mirred ingress mirror dev veth1 tc filter add dev veth0 egress chain 0 protocol ip flower ct_state -inv action ct commit action goto chain 1 tc qdisc add dev veth1 clsact tc filter add dev veth1 ingress chain 0 protocol ip flower ct_state +trk action drop ping & tc -s filter show dev veth1 ingress With command 'tc -s filter show', we can find the pkts were dropped on veth1. Fixes: b57dc7c13ea9 ("net/sched: Introduce action ct") Signed-off-by: Roi Dayan Signed-off-by: Hangbin Liu Signed-off-by: David S. Miller --- net/sched/act_mirred.c | 3 +++ 1 file changed, 3 insertions(+) diff --git a/net/sched/act_mirred.c b/net/sched/act_mirred.c index 7153c67f641e..2ef4cd2c848b 100644 --- a/net/sched/act_mirred.c +++ b/net/sched/act_mirred.c @@ -273,6 +273,9 @@ static int tcf_mirred_act(struct sk_buff *skb, const struct tc_action *a, goto out; } + /* All mirred/redirected skbs should clear previous ct info */ + nf_reset_ct(skb2); + want_ingress = tcf_mirred_act_wants_ingress(m_eaction); expects_nh = want_ingress || !m_mac_header_xmit;