From: Neal Cardwell <ncardw...@google.com>
Date: Tue, 30 Aug 2016 11:55:23 -0400
> Yuchung noticed that on the first TFO server data packet sent after
> the (TFO) handshake, the server echoed the TCP timestamp value in the
> SYN/data instead of the timestamp value in the final ACK of the
> handshake. This problem did not happen on regular opens.
>
> The tcp_replace_ts_recent() logic that decides whether to remember an
> incoming TS value needs tp->rcv_wup to hold the latest receive
> sequence number that we have ACKed (latest tp->rcv_nxt we have
> ACKed). This commit fixes this issue by ensuring that a TFO server
> properly updates tp->rcv_wup to match tp->rcv_nxt at the time it sends
> a SYN/ACK for the SYN/data.
>
> Reported-by: Yuchung Cheng <ych...@google.com>
> Signed-off-by: Neal Cardwell <ncardw...@google.com>
> Signed-off-by: Yuchung Cheng <ych...@google.com>
> Signed-off-by: Eric Dumazet <eduma...@google.com>
> Signed-off-by: Soheil Hassas Yeganeh <soh...@google.com>
> Fixes: 168a8f58059a ("tcp: TCP Fast Open Server - main code path")
Applied to 'net', thanks.
