From ca7c8034d2df59ea5d67d5ea24b21844db361e48 Mon Sep 17 00:00:00 2001
From: Martin Renters <martin@FreeBSD.org>
Date: Wed, 3 Jul 1996 21:43:48 +0000
Subject: [PATCH] Check if username is a NULL pointer before dereferencing it.

---
 usr.sbin/pwd_mkdb/pwd_mkdb.c | 2 +-
 1 file changed, 1 insertion(+), 1 deletion(-)

diff --git a/usr.sbin/pwd_mkdb/pwd_mkdb.c b/usr.sbin/pwd_mkdb/pwd_mkdb.c
index fc2f893cee6a..14df8125ee91 100644
--- a/usr.sbin/pwd_mkdb/pwd_mkdb.c
+++ b/usr.sbin/pwd_mkdb/pwd_mkdb.c
@@ -125,7 +125,7 @@ main(argc, argv)
 	argc -= optind;
 	argv += optind;
 
-	if (argc != 1 || *username == '+' || *username == '-')
+	if (argc != 1 || (username && (*username == '+' || *username == '-')))
 		usage();
 
 	/*