From 66666948f98e4fc5e5011431986772e1dd652197 Mon Sep 17 00:00:00 2001
From: xueyunfei <xueyunfei@espressif.com>
Date: Mon, 20 Jan 2020 17:14:44 +0800
Subject: [PATCH] sockets: Fix free-select-locked  after udp close

ESP_LWIP supports closing socket while waiting. This fixes potential
races.
Orig: fix bug for after udp close select_waiting assert (dd3b3017)

Ref IDF-4794
---
 src/api/sockets.c | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/api/sockets.c b/src/api/sockets.c
index d2ca56498..2d4c9b4a6 100644
--- a/src/api/sockets.c
+++ b/src/api/sockets.c
@@ -565,6 +565,9 @@ free_socket_locked(struct lwip_sock *sock, int is_tcp, struct netconn **conn,
 
   *lastdata = sock->lastdata;
   sock->lastdata.pbuf = NULL;
+#if ESP_LWIP
+  sock->select_waiting = 0;
+#endif /* ESP_LWIP */
   *conn = sock->conn;
   sock->conn = NULL;
   return 1;