From ac7eeea44d7312c1be4c6170468873be141d0d6b Mon Sep 17 00:00:00 2001
From: Simon Kelley <simon@thekelleys.org.uk>
Date: Wed, 21 Jul 2021 00:15:15 +0100
Subject: [PATCH] Handle empty hostmaster in --auth-soa

Spotted by Max Julian Hofmann and the Advanced Research Team at CrowdStrike
---
 src/option.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/src/option.c b/src/option.c
index 4c3df8a..03feb29 100644
--- a/src/option.c
+++ b/src/option.c
@@ -2231,7 +2231,7 @@ static int one_opt(int option, char *arg, char *errstr, char *gen_err, int comma
 	  arg = comma;
 	  comma = split(arg);
 	  daemon->hostmaster = opt_string_alloc(arg);
-	  for (cp = daemon->hostmaster; *cp; cp++)
+	  for (cp = daemon->hostmaster; cp && *cp; cp++)
 	    if (*cp == '@')
 	      *cp = '.';