pass "e" to fopen() to set O_CLOEXEC

ok guenther

lib/libutil/login_fbtab.c

@@ -1,4 +1,4 @@
-/*	$OpenBSD: login_fbtab.c,v 1.21 2025/11/24 12:44:25 jca Exp $	*/
+/*	$OpenBSD: login_fbtab.c,v 1.22 2026/03/11 14:59:10 deraadt Exp $	*/
 
 /************************************************************************
 * Copyright 1995 by Wietse Venema.  All rights reserved.  Some individual
@@ -87,7 +87,7 @@ login_fbtab(const char *tty, uid_t uid, gid_t gid)
 	mode_t	prot;
 	ssize_t	len;
 
-	if ((fp = fopen(_PATH_FBTAB, "r")) == NULL)
+	if ((fp = fopen(_PATH_FBTAB, "re")) == NULL)
 		return;
 
 	while ((len = getline(&buf, &bufsize, fp)) != -1) {

lib/libutil/passwd.c

@@ -1,4 +1,4 @@
-/*	$OpenBSD: passwd.c,v 1.56 2019/06/28 13:32:43 deraadt Exp $	*/
+/*	$OpenBSD: passwd.c,v 1.57 2026/03/11 14:59:10 deraadt Exp $	*/
 
 /*
  * Copyright (c) 1987, 1993, 1994, 1995
@@ -324,9 +324,9 @@ pw_copy(int ffd, int tfd, const struct passwd *pw, const struct passwd *opw)
 
 	if (!master)
 		pw_error(NULL, 0, 1);
-	if (!(from = fdopen(ffd, "r")))
+	if (!(from = fdopen(ffd, "re")))
 		pw_error(master, 1, 1);
-	if (!(to = fdopen(tfd, "w")))
+	if (!(to = fdopen(tfd, "we")))
 		pw_error(pw_lck ? pw_lck : NULL, pw_lck ? 1 : 0, 1);
 
 	for (done = 0; fgets(buf, (int)sizeof(buf), from);) {

lib/libutil/pidfile.c

@@ -1,4 +1,4 @@
-/*	$OpenBSD: pidfile.c,v 1.14 2019/06/28 14:20:40 schwarze Exp $	*/
+/*	$OpenBSD: pidfile.c,v 1.15 2026/03/11 14:59:10 deraadt Exp $	*/
 /*	$NetBSD: pidfile.c,v 1.4 2001/02/19 22:43:42 cgd Exp $	*/
 
 /*-
@@ -62,7 +62,7 @@ pidfile(const char *basename)
 	if (asprintf(&pidfile_path, "%s%s.pid", _PATH_VARRUN, basename) == -1)
 		return (-1);
 
-	if ((f = fopen(pidfile_path, "w")) == NULL) {
+	if ((f = fopen(pidfile_path, "we")) == NULL) {
 		save_errno = errno;
 		free(pidfile_path);
 		pidfile_path = NULL;