--- a/net/ipv6/tcp_ipv6.c +++ b/net/ipv6/tcp_ipv6.c @@ -540,7 +540,7 @@ static int tcp_v6_send_synack(const stru opt = ireq->ipv6_opt; if (!opt) opt = rcu_dereference(np->opt); - err = ip6_xmit(sk, skb, fl6, sk->sk_mark, opt, + err = ip6_xmit(sk, skb, fl6, skb->mark ? : sk->sk_mark, opt, tclass, sk->sk_priority); rcu_read_unlock(); err = net_xmit_eval(err);