From 72b3135830824e441d2dd5c23c030e5dd9f07f5a Mon Sep 17 00:00:00 2001
From: Guus Sliepen <guus@sliepen.org>
Date: Fri, 13 Mar 2020 08:45:44 +0100
Subject: [PATCH] Fix congestion window size after a triplicate ACK

---
 utcp.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/utcp.c b/utcp.c
index 3a6c506..d7bec9b 100644
--- a/utcp.c
+++ b/utcp.c
@@ -1454,7 +1454,7 @@ synack:
 
 				// RFC 5681 fast recovery
 				c->snd.ssthresh = max(c->snd.cwnd / 2, utcp->mtu * 2); // eq. 4
-				c->snd.cwnd = max(c->snd.ssthresh + 3 * utcp->mtu, c->sndbuf.maxsize);
+				c->snd.cwnd = min(c->snd.ssthresh + 3 * utcp->mtu, c->sndbuf.maxsize);
 
 				if(c->snd.cwnd > c->sndbuf.maxsize) {
 					c->snd.cwnd = c->sndbuf.maxsize;
-- 
2.39.5