Index: sys/kern/kern_time.c
===================================================================
--- sys/kern/kern_time.c
+++ sys/kern/kern_time.c
@@ -1652,6 +1652,8 @@
 
 	if (ts->tv_sec < 0 || ts->tv_nsec < 0 || ts->tv_nsec >= 1000000000)
 		return (EINVAL);
+	if ((UINT64_MAX - ts->tv_nsec) / 1000000000 < ts->tv_sec)
+		return (EINVAL);
 	if (ts->tv_sec == 0 && ts->tv_nsec != 0 && ts->tv_nsec < tick * 1000)
 		ts->tv_nsec = tick * 1000;
 	return (0);