From f13c986a208db54a23104933aef8980de032f1b2 Mon Sep 17 00:00:00 2001
From: Angus Gratton <angus@espressif.com>
Date: Mon, 2 Mar 2020 17:25:15 +1100
Subject: [PATCH] tcp: Fix assertion if tcp_kill_state() is called from
 tcp_alloc() to clean FIN_WAIT sockets

As reported on GitHub: https://github.com/espressif/esp-idf/issues/1194#issuecomment-585251932
---
 src/core/tcp.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/core/tcp.c b/src/core/tcp.c
index 3f3aac94..c85ca5e2 100644
--- a/src/core/tcp.c
+++ b/src/core/tcp.c
@@ -1755,6 +1755,10 @@ tcp_kill_state(enum tcp_state state)
   struct tcp_pcb *pcb, *inactive;
   u32_t inactivity;
 
+#if !ESP_LWIP
+  LWIP_ASSERT("invalid state", (state == CLOSING) || (state == LAST_ACK));
+#endif
+
   inactivity = 0;
   inactive = NULL;
   /* Go through the list of active pcbs and get the oldest pcb that is in state