From 3a218ec2a02008c95fe33ffb9cfa95068d50a1e8 Mon Sep 17 00:00:00 2001
From: David Lin <linpeng1577@gmail.com>
Date: Mon, 10 Aug 2020 18:20:37 +0800
Subject: [PATCH] Update bc35_28_95_lwm2m.c

    if (!str)
    {
        return -1;
    }
---
 devices/bc35_28_95_lwm2m/bc35_28_95_lwm2m.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/devices/bc35_28_95_lwm2m/bc35_28_95_lwm2m.c b/devices/bc35_28_95_lwm2m/bc35_28_95_lwm2m.c
index 4a980b87..70f04dbc 100644
--- a/devices/bc35_28_95_lwm2m/bc35_28_95_lwm2m.c
+++ b/devices/bc35_28_95_lwm2m/bc35_28_95_lwm2m.c
@@ -158,6 +158,10 @@ static int bc35_28_95_signal_quality_check(void)
     }
 
     str = strstr(echo.buffer, "+CSQ:");
+    if (!str) 
+    {
+        return -1;
+    }
     sscanf(str, "+CSQ:%d,%d", &rssi, &ber);
     if (rssi == 99) {
         return -1;