From 7adab74ed57c9bc847f16b82652325b7a775c3a6 Mon Sep 17 00:00:00 2001
From: nicandris <nicandris@gmail.com>
Date: Sat, 19 Sep 2020 14:02:15 +0200
Subject: [PATCH] Fix possible buffer overflow

---
 tasmota/xdrv_23_zigbee_2_devices.ino | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/tasmota/xdrv_23_zigbee_2_devices.ino b/tasmota/xdrv_23_zigbee_2_devices.ino
index a5a3ab2f9..26667786a 100644
--- a/tasmota/xdrv_23_zigbee_2_devices.ino
+++ b/tasmota/xdrv_23_zigbee_2_devices.ino
@@ -897,8 +897,8 @@ void Z_Devices::jsonPublishFlush(uint16_t shortaddr) {
 
     if (Settings.flag4.zigbee_distinct_topics) {
       if (Settings.flag4.zb_topic_fname && fname) {
-        char frtopic[13];
-        snprintf_P(frtopic, sizeof(frtopic) + strlen(fname), PSTR("tele/%s/" D_RSLT_SENSOR), fname);
+        char frtopic[13 + strlen(fname)];
+        snprintf_P(frtopic, sizeof(frtopic), PSTR("tele/%s/" D_RSLT_SENSOR), fname);
         MqttPublish(frtopic, Settings.flag.mqtt_sensor_retain);
       } else {
         char subtopic[16];