From 428308e2cbd48fc912f40ac34869ef02a70fdfaf Mon Sep 17 00:00:00 2001
From: "Roger A. Light" <roger@atchoo.org>
Date: Fri, 9 Jan 2026 22:15:34 +0000
Subject: [PATCH] Fix crash when loading invalid persistence file.

Closes oss-fuzz #474389119. Regression in unreleased code.
---
 src/persist_read_v234.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/persist_read_v234.c b/src/persist_read_v234.c
index c5a586dfa..04a69c54c 100644
--- a/src/persist_read_v234.c
+++ b/src/persist_read_v234.c
@@ -163,6 +163,10 @@ int persist__chunk_base_msg_read_v234(FILE *db_fptr, struct P_base_msg *chunk, u
 	if(rc){
 		goto error;
 	}
+	if(!chunk->topic){
+		rc = MOSQ_ERR_INVAL;
+		goto error;
+	}
 	slen = strlen(chunk->topic);
 	if(slen > UINT16_MAX){
 		rc = MOSQ_ERR_INVAL;