5 files changed, 38 insertions, 12 deletions

diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
index d67ef56ca9bc..a0ee81f49a87 100644
--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -786,7 +786,8 @@ static int alarm_timer_nsleep(const clockid_t which_clock, int flags,
 	/* Convert (if necessary) to absolute time */
 	if (flags != TIMER_ABSTIME) {
 		ktime_t now = alarm_bases[type].gettime();
-		exp = ktime_add(now, exp);
+
+		exp = ktime_add_safe(now, exp);
 	}
 
 	if (alarmtimer_do_nsleep(&alarm, exp))
diff --git a/kernel/time/posix-cpu-timers.c b/kernel/time/posix-cpu-timers.c
index 39008d78927a..21a27bb73587 100644
--- a/kernel/time/posix-cpu-timers.c
+++ b/kernel/time/posix-cpu-timers.c
@@ -103,7 +103,7 @@ static void bump_cpu_timer(struct k_itimer *timer,
 			continue;
 
 		timer->it.cpu.expires += incr;
-		timer->it_overrun += 1 << i;
+		timer->it_overrun += 1LL << i;
 		delta -= incr;
 	}
 }
diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c
index fc7c37ad90a0..0e6ed2e7d066 100644
--- a/kernel/time/posix-timers.c
+++ b/kernel/time/posix-timers.c
@@ -355,6 +355,17 @@ static __init int init_posix_timers(void)
 
 __initcall(init_posix_timers);
 
+/*
+ * The siginfo si_overrun field and the return value of timer_getoverrun(2)
+ * are of type int. Clamp the overrun value to INT_MAX
+ */
+static inline int timer_overrun_to_int(struct k_itimer *timr, int baseval)
+{
+	s64 sum = timr->it_overrun_last + (s64)baseval;
+
+	return sum > (s64)INT_MAX ? INT_MAX : (int)sum;
+}
+
 static void schedule_next_timer(struct k_itimer *timr)
 {
 	struct hrtimer *timer = &timr->it.real.timer;
@@ -362,12 +373,11 @@ static void schedule_next_timer(struct k_itimer *timr)
 	if (timr->it.real.interval.tv64 == 0)
 		return;
 
-	timr->it_overrun += (unsigned int) hrtimer_forward(timer,
-						timer->base->get_time(),
-						timr->it.real.interval);
+	timr->it_overrun += hrtimer_forward(timer, timer->base->get_time(),
+					    timr->it.real.interval);
 
 	timr->it_overrun_last = timr->it_overrun;
-	timr->it_overrun = -1;
+	timr->it_overrun = -1LL;
 	++timr->it_requeue_pending;
 	hrtimer_restart(timer);
 }
@@ -396,7 +406,7 @@ void do_schedule_next_timer(struct siginfo *info)
 		else
 			schedule_next_timer(timr);
 
-		info->si_overrun += timr->it_overrun_last;
+		info->si_overrun = timer_overrun_to_int(timr, info->si_overrun);
 	}
 
 	if (timr)
@@ -491,8 +501,7 @@ static enum hrtimer_restart posix_timer_fn(struct hrtimer *timer)
 					now = ktime_add(now, kj);
 			}
 #endif
-			timr->it_overrun += (unsigned int)
-				hrtimer_forward(timer, now,
+			timr->it_overrun += hrtimer_forward(timer, now,
 						timr->it.real.interval);
 			ret = HRTIMER_RESTART;
 			++timr->it_requeue_pending;
@@ -633,7 +642,7 @@ SYSCALL_DEFINE3(timer_create, const clockid_t, which_clock,
 	it_id_set = IT_ID_SET;
 	new_timer->it_id = (timer_t) new_timer_id;
 	new_timer->it_clock = which_clock;
-	new_timer->it_overrun = -1;
+	new_timer->it_overrun = -1LL;
 
 	if (timer_event_spec) {
 		if (copy_from_user(&event, timer_event_spec, sizeof (event))) {
@@ -762,7 +771,7 @@ common_timer_get(struct k_itimer *timr, struct itimerspec *cur_setting)
 	 */
 	if (iv.tv64 && (timr->it_requeue_pending & REQUEUE_PENDING ||
 			timr->it_sigev_notify == SIGEV_NONE))
-		timr->it_overrun += (unsigned int) hrtimer_forward(timer, now, iv);
+		timr->it_overrun += hrtimer_forward(timer, now, iv);
 
 	remaining = __hrtimer_expires_remaining_adjusted(timer, now);
 	/* Return 0 only, when the timer is expired and not pending */
@@ -824,7 +833,7 @@ SYSCALL_DEFINE1(timer_getoverrun, timer_t, timer_id)
 	if (!timr)
 		return -EINVAL;
 
-	overrun = timr->it_overrun_last;
+	overrun = timer_overrun_to_int(timr, 0);
 	unlock_timer(timr, flags);
 
 	return overrun;
diff --git a/kernel/time/time.c b/kernel/time/time.c
index 39468651a064..a5b6d98ea7b1 100644
--- a/kernel/time/time.c
+++ b/kernel/time/time.c
@@ -704,6 +704,16 @@ u64 nsec_to_clock_t(u64 x)
 #endif
 }
 
+u64 jiffies64_to_nsecs(u64 j)
+{
+#if !(NSEC_PER_SEC % HZ)
+	return (NSEC_PER_SEC / HZ) * j;
+# else
+	return div_u64(j * HZ_TO_NSEC_NUM, HZ_TO_NSEC_DEN);
+#endif
+}
+EXPORT_SYMBOL(jiffies64_to_nsecs);
+
 /**
  * nsecs_to_jiffies64 - Convert nsecs in u64 to jiffies64
  *
diff --git a/kernel/time/timeconst.bc b/kernel/time/timeconst.bc
index c48688904f9f..f83bbb81600b 100644
--- a/kernel/time/timeconst.bc
+++ b/kernel/time/timeconst.bc
@@ -98,6 +98,12 @@ define timeconst(hz) {
 		print "#define HZ_TO_USEC_DEN\t\t", hz/cd, "\n"
 		print "#define USEC_TO_HZ_NUM\t\t", hz/cd, "\n"
 		print "#define USEC_TO_HZ_DEN\t\t", 1000000/cd, "\n"
+
+		cd=gcd(hz,1000000000)
+		print "#define HZ_TO_NSEC_NUM\t\t", 1000000000/cd, "\n"
+		print "#define HZ_TO_NSEC_DEN\t\t", hz/cd, "\n"
+		print "#define NSEC_TO_HZ_NUM\t\t", hz/cd, "\n"
+		print "#define NSEC_TO_HZ_DEN\t\t", 1000000000/cd, "\n"
 		print "\n"
 
 		print "#endif /* KERNEL_TIMECONST_H */\n"