From a1fb286c06326f5d19277132f2599c0bc991279c Mon Sep 17 00:00:00 2001
From: jeromecoutant <jerome.coutant@st.com>
Date: Tue, 28 Jan 2020 11:06:06 +0100
Subject: [PATCH] AT_CellularStack: crash during TCP test

function tries to access _socket[1] whch is not opened
---
 features/cellular/framework/AT/AT_CellularStack.cpp | 6 ++++--
 1 file changed, 4 insertions(+), 2 deletions(-)

diff --git a/features/cellular/framework/AT/AT_CellularStack.cpp b/features/cellular/framework/AT/AT_CellularStack.cpp
index 912bd1072b..0cd3ac4c7f 100644
--- a/features/cellular/framework/AT/AT_CellularStack.cpp
+++ b/features/cellular/framework/AT/AT_CellularStack.cpp
@@ -429,8 +429,10 @@ void AT_CellularStack::socket_attach(nsapi_socket_t handle, void (*callback)(voi
 int AT_CellularStack::get_socket_index_by_port(uint16_t port)
 {
     for (int i = 0; i < _device.get_property(AT_CellularDevice::PROPERTY_SOCKET_COUNT); i++) {
-        if (_socket[i]->localAddress.get_port() == port) {
-            return i;
+        if (_socket[i] != 0) {
+            if (_socket[i]->localAddress.get_port() == port) {
+                return i;
+            }
         }
     }
     return -1;