diff --git a/net/ipv4/netfilter/ipt_SYNPROXY.c b/net/ipv4/netfilter/ipt_SYNPROXY.c index 94371db6aecc..90e489eb1c0a 100644 --- a/net/ipv4/netfilter/ipt_SYNPROXY.c +++ b/net/ipv4/netfilter/ipt_SYNPROXY.c @@ -269,7 +269,7 @@ synproxy_tg4(struct sk_buff *skb, const struct xt_action_param *par) synproxy_parse_options(skb, par->thoff, th, &opts); - if (th->syn && !th->ack) { + if (th->syn && !(th->ack || th->fin || th->rst)) { /* Initial SYN from client */ this_cpu_inc(snet->stats->syn_received); @@ -285,7 +285,7 @@ synproxy_tg4(struct sk_buff *skb, const struct xt_action_param *par) XT_SYNPROXY_OPT_ECN); synproxy_send_client_synack(skb, th, &opts); - } else if (th->ack && !(th->fin || th->rst)) + } else if (th->ack && !(th->fin || th->rst || th->syn)) /* ACK from client */ synproxy_recv_client_ack(snet, skb, th, &opts, ntohl(th->seq)); diff --git a/net/ipv6/netfilter/ip6t_SYNPROXY.c b/net/ipv6/netfilter/ip6t_SYNPROXY.c index 4270a9b145e5..a5af0bfef126 100644 --- a/net/ipv6/netfilter/ip6t_SYNPROXY.c +++ b/net/ipv6/netfilter/ip6t_SYNPROXY.c @@ -284,7 +284,7 @@ synproxy_tg6(struct sk_buff *skb, const struct xt_action_param *par) synproxy_parse_options(skb, par->thoff, th, &opts); - if (th->syn) { + if (th->syn && !(th->ack || th->fin || th->rst)) { /* Initial SYN from client */ this_cpu_inc(snet->stats->syn_received); @@ -300,7 +300,7 @@ synproxy_tg6(struct sk_buff *skb, const struct xt_action_param *par) XT_SYNPROXY_OPT_ECN); synproxy_send_client_synack(skb, th, &opts); - } else if (th->ack && !(th->fin || th->rst)) + } else if (th->ack && !(th->fin || th->rst || th->syn)) /* ACK from client */ synproxy_recv_client_ack(snet, skb, th, &opts, ntohl(th->seq));