From 2b04d177c76728a5a389a08a4a9a78238549a13a Mon Sep 17 00:00:00 2001
From: Laurent Louf <laurent@getmoona.com>
Date: Fri, 3 May 2019 12:05:29 +0200
Subject: [PATCH] Add a check when publishing data to verify that if some data
 length is set, data pointer cannot be NULL, in which case an error is
 returned.

Signed-off-by: Marius Vikhammer <marius.vikhammer@espressif.com>
---
 lib/mqtt_msg.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/lib/mqtt_msg.c b/lib/mqtt_msg.c
index 05ffa19..1d67119 100644
--- a/lib/mqtt_msg.c
+++ b/lib/mqtt_msg.c
@@ -430,6 +430,10 @@ mqtt_message_t *mqtt_msg_publish(mqtt_connection_t *connection, const char *topi
         return fail_message(connection);
     }
 
+    if (data == NULL && data_length > 0) {
+       return fail_message(connection);
+    }
+
     if (qos > 0) {
         if ((*message_id = append_message_id(connection, 0)) == 0) {
             return fail_message(connection);