From f65d8c0cbf72ad6f68502df771fb0c91a6c3185c Mon Sep 17 00:00:00 2001
From: Theo Arends <11044339+arendst@users.noreply.github.com>
Date: Mon, 24 Sep 2018 11:44:40 +0200
Subject: [PATCH] Fix possible array overflow

Fix possible array overflow (#3887 )
---
 sonoff/sonoff.ino | 3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/sonoff/sonoff.ino b/sonoff/sonoff.ino
index dc1445fc4..91c1fbb9b 100755
--- a/sonoff/sonoff.ino
+++ b/sonoff/sonoff.ino
@@ -462,10 +462,11 @@ void MqttDataHandler(char* topic, byte* data, unsigned int data_len)
 
   grpflg = (strstr(topicBuf, Settings.mqtt_grptopic) != NULL);
   fallback_topic_flag = (strstr(topicBuf, mqtt_client) != NULL);
-  type = strrchr(topicBuf, '/') +1;  // Last part of received topic is always the command (type)
+  type = strrchr(topicBuf, '/');  // Last part of received topic is always the command (type)
 
   index = 1;
   if (type != NULL) {
+    type++;
     for (i = 0; i < strlen(type); i++) {
       type[i] = toupper(type[i]);
     }