diff options
| author | jlemon <jlemon@FreeBSD.org> | 2003-02-26 18:20:41 +0000 |
|---|---|---|
| committer | jlemon <jlemon@FreeBSD.org> | 2003-02-26 18:20:41 +0000 |
| commit | d57f539d00971e49703bb5b1e12f05a1c6cd50fb (patch) | |
| tree | cd6504ec1d6b1d9d0c466b485cafeb5b53425e1c /sys/netinet/tcp_input.c | |
| parent | 55ad40591c6b9581452e25fff8526a772449db4f (diff) | |
| download | FreeBSD-src-d57f539d00971e49703bb5b1e12f05a1c6cd50fb.zip FreeBSD-src-d57f539d00971e49703bb5b1e12f05a1c6cd50fb.tar.gz | |
In timewait state, if the incoming segment is a pure in-sequence ack
that matches snd_max, then do not respond with an ack, just drop the
segment. This fixes a problem where a simultaneous close results in
an ack loop between two time-wait states.
Test case supplied by: Tim Robbins <tjr@FreeBSD.ORG>
Sponsored by: DARPA, NAI Labs
Diffstat (limited to 'sys/netinet/tcp_input.c')
| -rw-r--r-- | sys/netinet/tcp_input.c | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/sys/netinet/tcp_input.c b/sys/netinet/tcp_input.c index 2fec783..7b4827a 100644 --- a/sys/netinet/tcp_input.c +++ b/sys/netinet/tcp_input.c @@ -2913,9 +2913,11 @@ tcp_timewait(tw, to, th, m, tlen) } /* - * Acknowlege the segment, then drop it. + * Acknowledge the segment if it has data or is not a duplicate ACK. */ - tcp_twrespond(tw, TH_ACK); + if (thflags != TH_ACK || tlen != 0 || + th->th_seq != tw->rcv_nxt || th->th_ack != tw->snd_nxt) + tcp_twrespond(tw, TH_ACK); goto drop; reset: |
