From fe21241ee0268b3740a1e9980201115775a8d191 Mon Sep 17 00:00:00 2001
From: Konstantin Belousov <kib@FreeBSD.org>
Date: Fri, 12 Dec 2014 09:37:18 +0000
Subject: [PATCH] For architectures where time_t is wide enough, in particular,
 64bit platforms, avoid overflow after year 2038 in clock_ct_to_ts().

PR:	195868
Reviewed by:	bde
Sponsored by:	The FreeBSD Foundation
MFC after:	1 week
---
 sys/kern/subr_clock.c | 8 +++-----
 1 file changed, 3 insertions(+), 5 deletions(-)

diff --git a/sys/kern/subr_clock.c b/sys/kern/subr_clock.c
index f30f529dbdba..05de5b94c819 100644
--- a/sys/kern/subr_clock.c
+++ b/sys/kern/subr_clock.c
@@ -133,7 +133,6 @@ print_ct(struct clocktime *ct)
 int
 clock_ct_to_ts(struct clocktime *ct, struct timespec *ts)
 {
-	time_t secs;
 	int i, year, days;
 
 	year = ct->year;
@@ -167,11 +166,10 @@ clock_ct_to_ts(struct clocktime *ct, struct timespec *ts)
 	  	days += days_in_month(year, i);
 	days += (ct->day - 1);
 
-	/* Add hours, minutes, seconds. */
-	secs = ((days * 24 + ct->hour) * 60 + ct->min) * 60 + ct->sec;
-
-	ts->tv_sec = secs;
+	ts->tv_sec = (((time_t)days * 24 + ct->hour) * 60 + ct->min) * 60 +
+	    ct->sec;
 	ts->tv_nsec = ct->nsec;
+
 	if (ct_debug)
 		printf(" = %ld.%09ld\n", (long)ts->tv_sec, (long)ts->tv_nsec);
 	return (0);