diff options
| author | friehm <friehm@cvs.openbsd.org> | 2018-09-17 14:07:49 +0000 |
|---|---|---|
| committer | friehm <friehm@cvs.openbsd.org> | 2018-09-17 14:07:49 +0000 |
| commit | b8fa2c65c5b53e6be3413c67b27d7dd32834e8aa (patch) | |
| tree | 481af08caa757427f3f0cb099f159bf5a6a65b12 | |
| parent | ae66c8fad14a8c9f7cdf0c0e32bfb6819264a9db (diff) | |
Do not acknowledge a received ack-only tcp packet that we would drop due to
PAWS. Otherwise we could trigger a retransmit of the opposite party with another
wrong timestamp and produce loop. I have seen this with a buggy server which
messed up tcp timestamps.
Suggested by Prof. Jacobson for FreeBSD.
ok krw, bluhm, henning, mpi
| -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 899471dbbcc..0244e2907ab 100644 --- a/sys/netinet/tcp_input.c +++ b/sys/netinet/tcp_input.c @@ -1,4 +1,4 @@ -/* $OpenBSD: tcp_input.c,v 1.358 2018/07/23 21:14:00 bluhm Exp $ */ +/* $OpenBSD: tcp_input.c,v 1.359 2018/09/17 14:07:48 friehm Exp $ */ /* $NetBSD: tcp_input.c,v 1.23 1996/02/13 23:43:44 christos Exp $ */ /* @@ -1270,7 +1270,9 @@ trimthenstep6: } else { tcpstat_pkt(tcps_rcvduppack, tcps_rcvdupbyte, tlen); tcpstat_inc(tcps_pawsdrop); - goto dropafterack; + if (tlen) + goto dropafterack; + goto drop; } } |