From c7edfdf98753a0439dba5a74b20f38606cf1dd39 Mon Sep 17 00:00:00 2001
From: goldsimon <goldsimon@gmx.de>
Date: Fri, 25 Aug 2017 21:16:59 +0200
Subject: [PATCH] Fix bug #51765 and fix commit 90873d6: call tcp_rexmit_fast()
 more than once on dupacks since the actual transmission is guarded by
 TF_INFR, not by pcb->dupacks

---
 src/core/tcp_in.c | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/src/core/tcp_in.c b/src/core/tcp_in.c
index 53c61b14..c15a4099 100644
--- a/src/core/tcp_in.c
+++ b/src/core/tcp_in.c
@@ -1157,7 +1157,8 @@ tcp_receive(struct tcp_pcb *pcb)
               if (pcb->dupacks > 3) {
                 /* Inflate the congestion window */
                 TCP_WND_INC(pcb->cwnd, pcb->mss);
-              } else if (pcb->dupacks >= 3) {
+              }
+              if (pcb->dupacks >= 3) {
                 /* Do fast retransmit (checked via TF_INFR, not via dupacks count) */
                 tcp_rexmit_fast(pcb);
               }