diff options
| author | Alexander Bluhm <bluhm@cvs.openbsd.org> | 2021-08-09 17:03:09 +0000 |
|---|---|---|
| committer | Alexander Bluhm <bluhm@cvs.openbsd.org> | 2021-08-09 17:03:09 +0000 |
| commit | 07e61cea9f1dc494c4b9d3f3b3c060564c4c9936 (patch) | |
| tree | d56811fb28d04e881ed3d3fec0611ab2876c6146 /sys/netinet | |
| parent | 0f6b5bf9774997a0541b21af6d7df35944e8e062 (diff) | |
During unidirectional data transmission, a TCP connection may stall.
The sending machine is doing zero window probes, but is not sending
any more data although the other machine announced that it has space
again. The header prediction code did not update snd_wl2. If there
was a sequence number wrap, the send window update block is not
reached.
Update snd_wl2 when receiving predicted ACKs and and update snd_wl1
and rcv_up for predicted pure data.
from FreeBSD; OK sashan@ claudio@
Diffstat (limited to 'sys/netinet')
| -rw-r--r-- | sys/netinet/tcp_input.c | 8 |
1 files changed, 7 insertions, 1 deletions
diff --git a/sys/netinet/tcp_input.c b/sys/netinet/tcp_input.c index 94cba7a4df6..288cfa87706 100644 --- a/sys/netinet/tcp_input.c +++ b/sys/netinet/tcp_input.c @@ -1,4 +1,4 @@ -/* $OpenBSD: tcp_input.c,v 1.369 2021/08/09 16:06:31 bluhm Exp $ */ +/* $OpenBSD: tcp_input.c,v 1.370 2021/08/09 17:03:08 bluhm Exp $ */ /* $NetBSD: tcp_input.c,v 1.23 1996/02/13 23:43:44 christos Exp $ */ /* @@ -966,6 +966,8 @@ findpcb: tp->t_pmtud_mss_acked = acked; tp->snd_una = th->th_ack; + /* Pull snd_wl2 up to prevent seq wrap. */ + tp->snd_wl2 = th->th_ack; /* * We want snd_last to track snd_una so * as to avoid sequence wraparound problems @@ -1015,6 +1017,10 @@ findpcb: tcp_clean_sackreport(tp); tcpstat_inc(tcps_preddat); tp->rcv_nxt += tlen; + /* Pull snd_wl1 and rcv_up up to prevent seq wrap. */ + tp->snd_wl1 = th->th_seq; + /* Packet has most recent segment, no urgent exists. */ + tp->rcv_up = tp->rcv_nxt; tcpstat_pkt(tcps_rcvpack, tcps_rcvbyte, tlen); ND6_HINT(tp); |