Author: rscheff Date: Thu May 21 21:26:21 2020 New Revision: 361346 URL: https://svnweb.freebsd.org/changeset/base/361346
Log: Retain only mutually supported TCP options after simultaneous SYN When receiving a parallel SYN in SYN-SENT state, remove all the options only we supported locally before sending the SYN,ACK. This addresses a consistency issue on parallel opens. Also, on such a parallel open, the stack could be coaxed into running with timestamps enabled, even if administratively disabled. Reviewed by: tuexen (mentor) Approved by: tuexen (mentor) MFC after: 2 weeks Sponsored by: NetApp, Inc. Differential Revision: https://reviews.freebsd.org/D23371 Modified: head/sys/netinet/tcp_input.c head/sys/netinet/tcp_stacks/bbr.c head/sys/netinet/tcp_stacks/rack.c Modified: head/sys/netinet/tcp_input.c ============================================================================== --- head/sys/netinet/tcp_input.c Thu May 21 21:15:25 2020 (r361345) +++ head/sys/netinet/tcp_input.c Thu May 21 21:26:21 2020 (r361346) @@ -1623,17 +1623,20 @@ tcp_do_segment(struct mbuf *m, struct tcphdr *th, stru (tp->t_flags & TF_REQ_SCALE)) { tp->t_flags |= TF_RCVD_SCALE; tp->snd_scale = to.to_wscale; - } + } else + tp->t_flags &= ~TF_REQ_SCALE; /* * Initial send window. It will be updated with * the next incoming segment to the scaled value. */ tp->snd_wnd = th->th_win; - if (to.to_flags & TOF_TS) { + if ((to.to_flags & TOF_TS) && + (tp->t_flags & TF_REQ_TSTMP)) { tp->t_flags |= TF_RCVD_TSTMP; tp->ts_recent = to.to_tsval; tp->ts_recent_age = tcp_ts_getticks(); - } + } else + tp->t_flags &= ~TF_REQ_TSTMP; if (to.to_flags & TOF_MSS) tcp_mss(tp, to.to_mss); if ((tp->t_flags & TF_SACK_PERMIT) && Modified: head/sys/netinet/tcp_stacks/bbr.c ============================================================================== --- head/sys/netinet/tcp_stacks/bbr.c Thu May 21 21:15:25 2020 (r361345) +++ head/sys/netinet/tcp_stacks/bbr.c Thu May 21 21:26:21 2020 (r361346) @@ -11595,17 +11595,20 @@ bbr_do_segment_nounlock(struct mbuf *m, struct tcphdr (tp->t_flags & TF_REQ_SCALE)) { tp->t_flags |= TF_RCVD_SCALE; tp->snd_scale = to.to_wscale; - } + } else + tp->t_flags &= ~TF_REQ_SCALE; /* * Initial send window. It will be updated with the * next incoming segment to the scaled value. */ tp->snd_wnd = th->th_win; - if (to.to_flags & TOF_TS) { + if ((to.to_flags & TOF_TS) && + (tp->t_flags & TF_REQ_TSTMP)) { tp->t_flags |= TF_RCVD_TSTMP; tp->ts_recent = to.to_tsval; tp->ts_recent_age = tcp_tv_to_mssectick(&bbr->rc_tv); - } + } else + tp->t_flags &= ~TF_REQ_TSTMP; if (to.to_flags & TOF_MSS) tcp_mss(tp, to.to_mss); if ((tp->t_flags & TF_SACK_PERMIT) && Modified: head/sys/netinet/tcp_stacks/rack.c ============================================================================== --- head/sys/netinet/tcp_stacks/rack.c Thu May 21 21:15:25 2020 (r361345) +++ head/sys/netinet/tcp_stacks/rack.c Thu May 21 21:26:21 2020 (r361346) @@ -11082,17 +11082,20 @@ rack_do_segment_nounlock(struct mbuf *m, struct tcphdr (tp->t_flags & TF_REQ_SCALE)) { tp->t_flags |= TF_RCVD_SCALE; tp->snd_scale = to.to_wscale; - } + } else + tp->t_flags &= ~TF_REQ_SCALE; /* * Initial send window. It will be updated with the * next incoming segment to the scaled value. */ tp->snd_wnd = th->th_win; - if (to.to_flags & TOF_TS) { + if ((to.to_flags & TOF_TS) && + (tp->t_flags & TF_REQ_TSTMP)) { tp->t_flags |= TF_RCVD_TSTMP; tp->ts_recent = to.to_tsval; tp->ts_recent_age = cts; - } + } else + tp->t_flags &= ~TF_REQ_TSTMP; if (to.to_flags & TOF_MSS) tcp_mss(tp, to.to_mss); if ((tp->t_flags & TF_SACK_PERMIT) && _______________________________________________ svn-src-head@freebsd.org mailing list https://lists.freebsd.org/mailman/listinfo/svn-src-head To unsubscribe, send any mail to "svn-src-head-unsubscr...@freebsd.org"
