Commit cd171461 authored by Eric Dumazet's avatar Eric Dumazet Committed by Jakub Kicinski
Browse files

tcp: fix initial tp->rcvq_space.space value for passive TS enabled flows 



tcp_rcv_state_process() must tweak tp->advmss for TS enabled flows
before the call to tcp_init_transfer() / tcp_init_buffer_space().

Otherwise tp->rcvq_space.space is off by 120 bytes
(TCP_INIT_CWND * TCPOLEN_TSTAMP_ALIGNED).

Signed-off-by: default avatarEric Dumazet <edumazet@google.com>
Reviewed-by: default avatarWei Wang <weiwan@google.com>
Link: https://patch.msgid.link/20250513193919.1089692-7-edumazet@google.com


Signed-off-by: default avatarJakub Kicinski <kuba@kernel.org>
parent d59fc95b

net/ipv4/tcp_input.c

+3 −3
Original line number Diff line number Diff line
@@ -6872,6 +6872,9 @@ tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb) 
		if (!tp->srtt_us)

			tcp_synack_rtt_meas(sk, req);



		if (tp->rx_opt.tstamp_ok)

			tp->advmss -= TCPOLEN_TSTAMP_ALIGNED;



		if (req) {

			tcp_rcv_synrecv_state_fastopen(sk);

		} else {
@@ -6897,9 +6900,6 @@ tcp_rcv_state_process(struct sock *sk, struct sk_buff *skb) 
		tp->snd_wnd = ntohs(th->window) << tp->rx_opt.snd_wscale;

		tcp_init_wl(tp, TCP_SKB_CB(skb)->seq);



		if (tp->rx_opt.tstamp_ok)

			tp->advmss -= TCPOLEN_TSTAMP_ALIGNED;



		if (!inet_csk(sk)->icsk_ca_ops->cong_control)

			tcp_update_pacing_rate(sk);