diff --git a/lib/libwebsockets.c b/lib/libwebsockets.c
index 33bdb895..3c130469 100755
--- a/lib/libwebsockets.c
+++ b/lib/libwebsockets.c
@@ -432,7 +432,8 @@ just_kill_connection:
 	lws_remove_from_timeout_list(wsi);
 
 	/* checking return redundant since we anyway close */
-	remove_wsi_socket_from_fds(wsi);
+	if (wsi->sock != LWS_SOCK_INVALID)
+		remove_wsi_socket_from_fds(wsi);
 
 #if defined(LWS_WITH_ESP8266)
 	espconn_disconnect(wsi->sock);