diff options
| author | Michael Tuexen <tuexen@FreeBSD.org> | 2026-02-25 13:06:15 +0000 |
|---|---|---|
| committer | Michael Tuexen <tuexen@FreeBSD.org> | 2026-02-25 13:06:15 +0000 |
| commit | f3364d3c8c876074a9a6f68168e5eb8bd60207de (patch) | |
| tree | 28ae4ef17dcd0702dd5caf4c9594091aa4b78823 | |
| parent | 8d2f910ceb0f1c366bcf2146a5ba1d1074d07933 (diff) | |
tcp: improve handling of segments in TIME WAIT
The check for excluding duplicate ACKs needs to consider only TH_SYN
and TH_FIN. We know that TH_ACK is set and TH_RST is cleared. All
other flags, in particular TH_ECE, TH_CWR, and TH_AE needs to be
ignored for the check.
PR: 292293
Reviewed by: rrs
MFC after: 3 days
Sponsored by: Netflix, Inc.
Differential Revision: https://reviews.freebsd.org/D55489
| -rw-r--r-- | sys/netinet/tcp_timewait.c | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/sys/netinet/tcp_timewait.c b/sys/netinet/tcp_timewait.c index 847598422da5..ba5c90c91e43 100644 --- a/sys/netinet/tcp_timewait.c +++ b/sys/netinet/tcp_timewait.c @@ -287,7 +287,7 @@ tcp_twcheck(struct inpcb *inp, struct tcpopt *to, struct tcphdr *th, /* * Acknowledge the segment if it has data or is not a duplicate ACK. */ - if (thflags != TH_ACK || tlen != 0 || + if ((thflags & (TH_SYN | TH_FIN)) != 0 || tlen != 0 || th->th_seq != tp->rcv_nxt || th->th_ack != tp->snd_nxt) { TCP_LOG_EVENT(tp, th, NULL, NULL, TCP_LOG_IN, 0, tlen, NULL, true); |