From 31d2a2c6ddccf4b657eadbcdeef56c8b3bdfd592 Mon Sep 17 00:00:00 2001
From: Andy Green <andy@warmcat.com>
Date: Mon, 12 Dec 2016 20:41:05 +0800
Subject: [PATCH] client: avoid possible NULL deref on error path

https://github.com/warmcat/libwebsockets/issues/672
---
 lib/client-handshake.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/lib/client-handshake.c b/lib/client-handshake.c
index f78f4f1..904f6ec 100644
--- a/lib/client-handshake.c
+++ b/lib/client-handshake.c
@@ -311,8 +311,11 @@ lws_client_connect_2(struct lws *wsi)
 
 oom4:
 	/* we're closing, losing some rx is OK */
-	wsi->u.hdr.ah->rxpos = wsi->u.hdr.ah->rxlen;
+	if (wsi->u.hdr.ah)
+		wsi->u.hdr.ah->rxpos = wsi->u.hdr.ah->rxlen;
+
 	lws_header_table_detach(wsi);
+
 	/* take care that we might be inserted in fds already */
 	if (wsi->position_in_fds_table != -1)
 		goto failed;
-- 
2.7.4