From be425821c4bf87c743b8107c28804f3c67054943 Mon Sep 17 00:00:00 2001
From: millert <millert@openbsd.org>
Date: Fri, 21 Jan 2022 22:53:20 +0000
Subject: [PATCH] Treat ppoll(2) errors as fatal.  OK deraadt@

---
 usr.sbin/cron/cron.c | 28 ++++++++++++++++------------
 1 file changed, 16 insertions(+), 12 deletions(-)

diff --git a/usr.sbin/cron/cron.c b/usr.sbin/cron/cron.c
index 6fe8916141d..831a70d5411 100644
--- a/usr.sbin/cron/cron.c
+++ b/usr.sbin/cron/cron.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: cron.c,v 1.79 2020/04/16 17:51:56 millert Exp $	*/
+/*	$OpenBSD: cron.c,v 1.80 2022/01/21 22:53:20 millert Exp $	*/
 
 /* Copyright 1988,1990,1993,1994 by Paul Vixie
  * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
@@ -368,11 +368,21 @@ cron_sleep(time_t target, sigset_t *mask)
 
 		/* Sleep until we time out, get a poke, or get a signal. */
 		nfds = ppoll(pfd, 1, &timeout, mask);
-		if (nfds == 0)
-			break;		/* timer expired */
-		if (nfds == -1 && errno != EINTR)
-			break;		/* an error occurred */
-		if (nfds > 0) {
+		switch (nfds) {
+		case -1:
+			if (errno != EINTR && errno != EAGAIN)
+				err(EXIT_FAILURE, "ppoll");
+			if (errno == EINTR) {
+				if (got_sigchld) {
+					got_sigchld = 0;
+					sigchld_reaper();
+				}
+			}
+			break;
+		case 0:
+			/* done sleeping */
+			return;
+		default:
 			sunlen = sizeof(s_un);
 			fd = accept4(cronSock, (struct sockaddr *)&s_un,
 			    &sunlen, SOCK_NONBLOCK);
@@ -396,12 +406,6 @@ cron_sleep(time_t target, sigset_t *mask)
 						    batch_maxload, t2.tv_sec);
 				}
 			}
-		} else {
-			/* Interrupted by a signal. */
-			if (got_sigchld) {
-				got_sigchld = 0;
-				sigchld_reaper();
-			}
 		}
 
 		/* Adjust tv and continue where we left off.  */
-- 
2.20.1