From 1b39c563546aed677d0ac99b9fb8b44a5b48c1e4 Mon Sep 17 00:00:00 2001
From: Ralf Habacker <ralf.habacker@freenet.de>
Date: Mon, 24 Jun 2019 09:25:48 +0200
Subject: [PATCH] winbind: fix crash in fill_domain_username_talloc() if
 specified username is NULL

Signed-off-by: Ralf Habacker <ralf.habacker@freenet.de>
Reviewed-by: Andreas Schneider <asn@samba.org>
Reviewed-by: Jeremy Allison <jra@samba.org>

Autobuild-User(master): Jeremy Allison <jra@samba.org>
Autobuild-Date(master): Wed Jul  3 19:24:52 UTC 2019 on sn-devel-184
---
 source3/winbindd/winbindd_util.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/source3/winbindd/winbindd_util.c b/source3/winbindd/winbindd_util.c
index b79f90fb0ce..cc4c3f7391a 100644
--- a/source3/winbindd/winbindd_util.c
+++ b/source3/winbindd/winbindd_util.c
@@ -1693,6 +1693,10 @@ char *fill_domain_username_talloc(TALLOC_CTX *mem_ctx,
 		can_assume = false;
 	}
 
+	if (user == NULL) {
+		return NULL;
+	}
+
 	tmp_user = talloc_strdup(mem_ctx, user);
 	if (!strlower_m(tmp_user)) {
 		TALLOC_FREE(tmp_user);
-- 
2.47.3