From: Hoang Tran <tranviethoang.vn@gmail.com>
Date: Wed, 27 Sep 2017 16:30:58 +0000 (+0200)
Subject: tcp: fix under-evaluated ssthresh in TCP Vegas
X-Git-Url: https://git.stricted.de/?a=commitdiff_plain;h=0aaff15c10132eb36ab16b4785cd207075e5943b;p=GitHub%2FLineageOS%2Fandroid_kernel_motorola_exynos9610.git

tcp: fix under-evaluated ssthresh in TCP Vegas


[ Upstream commit cf5d74b85ef40c202c76d90959db4d850f301b95 ]

With the commit 76174004a0f19785 (tcp: do not slow start when cwnd equals
ssthresh), the comparison to the reduced cwnd in tcp_vegas_ssthresh() would
under-evaluate the ssthresh.

Signed-off-by: Hoang Tran <hoang.tran@uclouvain.be>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Sasha Levin <alexander.levin@verizon.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---

diff --git a/net/ipv4/tcp_vegas.c b/net/ipv4/tcp_vegas.c
index 218cfcc77650..ee113ff15fd0 100644
--- a/net/ipv4/tcp_vegas.c
+++ b/net/ipv4/tcp_vegas.c
@@ -158,7 +158,7 @@ EXPORT_SYMBOL_GPL(tcp_vegas_cwnd_event);
 
 static inline u32 tcp_vegas_ssthresh(struct tcp_sock *tp)
 {
-	return  min(tp->snd_ssthresh, tp->snd_cwnd-1);
+	return  min(tp->snd_ssthresh, tp->snd_cwnd);
 }
 
 static void tcp_vegas_cong_avoid(struct sock *sk, u32 ack, u32 acked)