From 9e5b8501815fb271727971ead6008ff2fd151231 Mon Sep 17 00:00:00 2001
From: "Roger A. Light" <roger@atchoo.org>
Date: Sun, 24 Oct 2021 14:23:57 +0100
Subject: [PATCH] Check for NULL before strcmp.

---
 src/database.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/database.c b/src/database.c
index 11d6ef34..df9778ba 100644
--- a/src/database.c
+++ b/src/database.c
@@ -453,7 +453,7 @@ int db__message_insert(struct mosquitto *context, uint16_t mid, enum mosquitto_m
 			&& dir == mosq_md_out && retain == false && stored->dest_ids){
 
 		for(i=0; i<stored->dest_id_count; i++){
-			if(!strcmp(stored->dest_ids[i], context->id)){
+			if(stored->dest_ids[i] && !strcmp(stored->dest_ids[i], context->id)){
 				/* We have already sent this message to this client. */
 				mosquitto_property_free_all(&properties);
 				return MOSQ_ERR_SUCCESS;