Add NULL dereference checks

iothub_client/src/message_queue.c

@@ -54,7 +54,15 @@ static bool find_item_by_message_ptr(LIST_ITEM_HANDLE list_item, const void* mat
     MESSAGE_QUEUE_ITEM* current_item = (MESSAGE_QUEUE_ITEM*)singlylinkedlist_item_get_value(list_item);
     MQ_MESSAGE_HANDLE* target_item = (MQ_MESSAGE_HANDLE*)match_context;
 
-    return (current_item->message == target_item);
+    if (current_item == NULL)
+    {
+        LogError("Failed finding item: current_item is NULL");
+        return false;
+    }
+    else
+    {
+        return (current_item->message == target_item);
+    }
 }
 
 static void fire_message_callback(MESSAGE_QUEUE_ITEM* mq_item, MESSAGE_QUEUE_RESULT result, void* reason)

serializer/src/codefirst.c

@@ -560,6 +560,12 @@ EXECUTE_COMMAND_RESULT CodeFirst_InvokeAction(DEVICE_HANDLE deviceHandle, void*
         result = EXECUTE_COMMAND_ERROR;
         LogError("parameterValues error %s ", MU_ENUM_TO_STRING(EXECUTE_COMMAND_RESULT, result));
     }
+    /*Codes_SRS_CODEFIRST_99_200:[ If devicHeader (callbackUserContext) is NULL then EXECUTE_COMMAND_ERROR shall be returned.]*/
+    else if (deviceHeader == NULL)
+    {
+        result = EXECUTE_COMMAND_ERROR;
+        LogError("callback User Context error %s ", MU_ENUM_TO_STRING(EXECUTE_COMMAND_RESULT, result));
+    }
     else
     {
         const REFLECTED_SOMETHING* something;
@@ -630,6 +636,11 @@ METHODRETURN_HANDLE CodeFirst_InvokeMethod(DEVICE_HANDLE deviceHandle, void* cal
         result = NULL;
         LogError("parameterValues error ");
     }
+    else if (deviceHeader == NULL)
+    {
+        result = NULL;
+        LogError("callback User Context error ");
+    }
     else
     {
         const REFLECTED_SOMETHING* something;