From 15c825712ee09c0da70b41fb8e3dbb37f5eddac7 Mon Sep 17 00:00:00 2001
From: "Jonathan T. Looney" <jtl@FreeBSD.org>
Date: Thu, 6 Oct 2016 16:00:48 +0000
Subject: [PATCH] Correctly calculate snd_max in persist case.

In the persist case, take the SYN and FIN flags into account when updating
the sequence space sent.

Reviewed by:	gnn
MFC after:	2 weeks
Sponsored by:	Juniper Networks, Netflix
Differential Revision:	https://reviews.freebsd.org/D7075
Tested by:	Limelight, Netflix
---
 sys/netinet/tcp_output.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/sys/netinet/tcp_output.c b/sys/netinet/tcp_output.c
index 454405149fe0..47630a0cb080 100644
--- a/sys/netinet/tcp_output.c
+++ b/sys/netinet/tcp_output.c
@@ -1519,7 +1519,7 @@ tcp_output(struct tcpcb *tp)
 			tp->t_flags |= TF_SENTFIN;
 		}
 		if (SEQ_GT(tp->snd_nxt + xlen, tp->snd_max))
-			tp->snd_max = tp->snd_nxt + len;
+			tp->snd_max = tp->snd_nxt + xlen;
 	}
 
 	if (error) {