act_mirred: clear sender cpu before sending to tx

[ Upstream commit d40496a5 ]

Similar to commit c29390c6 ("xps: must clear sender_cpu before forwarding")
the skb->sender_cpu needs to be cleared when moving from Rx
Tx, otherwise kernel could crash.

Fixes: 2bd82484 ("xps: fix xps for stacked devices")
Cc: Eric Dumazet <edumazet@google.com>
Cc: Jamal Hadi Salim <jhs@mojatatu.com>
Signed-off-by: Cong Wang <cwang@twopensource.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Acked-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

net/sched/act_mirred.c

@@ -168,6 +168,7 @@ static int tcf_mirred(struct sk_buff *skb, const struct tc_action *a,
 
 	skb2->skb_iif = skb->dev->ifindex;
 	skb2->dev = dev;
+	skb_sender_cpu_clear(skb2);
 	err = dev_queue_xmit(skb2);
 
 out: