@@ -115,6 +115,7 @@ struct tcp_request_sock {
u32 rcv_isn;
u32 snt_isn;
u32 snt_synack; /* synack sent time */
+ u32 last_oow_ack_time; /* last SYNACK */
u32 rcv_nxt; /* the ack # by SYNACK. For
* FastOpen it's the seq#
* after data-in-SYN.
@@ -1145,6 +1145,7 @@ static inline void tcp_openreq_init(struct request_sock *req,
tcp_rsk(req)->rcv_isn = TCP_SKB_CB(skb)->seq;
tcp_rsk(req)->rcv_nxt = TCP_SKB_CB(skb)->seq + 1;
tcp_rsk(req)->snt_synack = tcp_time_stamp;
+ tcp_rsk(req)->last_oow_ack_time = 0;
req->mss = rx_opt->mss_clamp;
req->ts_recent = rx_opt->saw_tstamp ? rx_opt->rcv_tsval : 0;
ireq->tstamp_ok = rx_opt->tstamp_ok;
@@ -605,7 +605,11 @@ struct sock *tcp_check_req(struct sock *sk, struct sk_buff *skb,
* Reset timer after retransmitting SYNACK, similar to
* the idea of fast retransmit in recovery.
*/
- if (!inet_rtx_syn_ack(sk, req))
+ if (!tcp_oow_rate_limited(sock_net(sk), skb,
+ LINUX_MIB_TCPACKSKIPPEDSYNRECV,
+ &tcp_rsk(req)->last_oow_ack_time) &&
+
+ !inet_rtx_syn_ack(sk, req))
req->expires = min(TCP_TIMEOUT_INIT << req->num_timeout,
TCP_RTO_MAX) + jiffies;
return NULL;