From: François Rigault <frigo@amadeus.com>
Date: Mon, 1 Nov 2021 12:54:25 +0000 (+0100)
Subject: groupdel: fix SIGSEGV when passwd does not exist
X-Git-Tag: 4.10~17^2
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=refs%2Fpull%2F435%2Fhead;p=thirdparty%2Fshadow.git

groupdel: fix SIGSEGV when passwd does not exist

When using groupdel with a prefix, groupdel will attempt to read a
passwd file to look for any user in the group. When the file does not
exist it cores with segmentation fault.

Resolves: https://bugzilla.redhat.com/show_bug.cgi?id=1986111
---

diff --git a/libmisc/prefix_flag.c b/libmisc/prefix_flag.c
index cca553a5b..b6628ac49 100644
--- a/libmisc/prefix_flag.c
+++ b/libmisc/prefix_flag.c
@@ -288,6 +288,9 @@ extern struct passwd* prefix_getpwent()
 	if (!passwd_db_file) {
 		return getpwent();
 	}
+	if (!fp_pwent) {
+		return NULL;
+	}
 	return fgetpwent(fp_pwent);
 }
 extern void prefix_endpwent()