diff options
| author |   frantzen <frantzen@openbsd.org> | 2004-04-26 18:12:25 +0000 |
|---|---|---|
| committer | frantzen <frantzen@openbsd.org> | 2004-04-26 18:12:25 +0000 |
| commit | 5011cf9884bedb774cdf82761a58d1af00975b2c (patch) | |
| tree | 1b4cd242c4f7a36f4fd56218d51e52996dfc4162 /sys/netinet/tcp_input.c | |
| parent | oh we need to model check and not crank > 256 for older cards... do that later (diff) | |
| download | wireguard-openbsd-5011cf9884bedb774cdf82761a58d1af00975b2c.tar.xz wireguard-openbsd-5011cf9884bedb774cdf82761a58d1af00975b2c.zip | |
- allow the user to force the TCP mss below the fail-safe 216 with a low
interface MTU.
- break a tcp_output() -> tcp_mtudisc() -> tcp_output() infinite recursion
when the TCP mss ends up larger than the interface MTU (when the if_mtu is
smaller than the tcp header). connections will still stall
feedback from itojun@, claudio@ and provos and testing from beck@
Diffstat (limited to 'sys/netinet/tcp_input.c')
| -rw-r--r-- | sys/netinet/tcp_input.c | 8 |
1 files changed, 5 insertions, 3 deletions
diff --git a/sys/netinet/tcp_input.c b/sys/netinet/tcp_input.c index f0cffa74bb5..57c2a850dae 100644 --- a/sys/netinet/tcp_input.c +++ b/sys/netinet/tcp_input.c @@ -1,4 +1,4 @@ -/* $OpenBSD: tcp_input.c,v 1.164 2004/04/20 20:05:29 markus Exp $ */ +/* $OpenBSD: tcp_input.c,v 1.165 2004/04/26 18:12:25 frantzen Exp $ */ /* $NetBSD: tcp_input.c,v 1.23 1996/02/13 23:43:44 christos Exp $ */ /* @@ -3068,13 +3068,15 @@ tcp_mss(tp, offer) * If we compute a larger value, return it for use in sending * a max seg size option, but don't store it for use * unless we received an offer at least that large from peer. - * However, do not accept offers under 216 bytes. + * However, do not accept offers under 216 bytes unless the + * interface MTU is actually that low. */ if (offer > 0) tp->t_peermss = offer; if (tp->t_peermss) mss = min(mss, tp->t_peermss); - mss = max(mss, 216); /* sanity - at least max opt. space */ + /* sanity - at least max opt. space */ + mss = max(mss, min(216, ifp->if_mtu - iphlen - sizeof(struct tcphdr))); /* * maxopd stores the maximum length of data AND options |