Merge branch 'bind_unbind' of git://git.kernel.org/pub/scm/linux/kernel/git/gregkh...

[GitHub/LineageOS/android_kernel_motorola_exynos9610.git] / kernel / time / alarmtimer.c

diff --git a/kernel/time/alarmtimer.c b/kernel/time/alarmtimer.c
index 5cb5b0008d9710c95c1af7ab8312b5e308b2c5d0..ee2f4202d82aa2acec5e438218a2405a4315f166 100644 (file)
--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -387,7 +387,7 @@ void alarm_start_relative(struct alarm *alarm, ktime_t start)
 {
        struct alarm_base *base = &alarm_bases[alarm->type];
 
-       start = ktime_add(start, base->gettime());
+       start = ktime_add_safe(start, base->gettime());
        alarm_start(alarm, start);
 }
 EXPORT_SYMBOL_GPL(alarm_start_relative);
@@ -475,7 +475,7 @@ u64 alarm_forward(struct alarm *alarm, ktime_t now, ktime_t interval)
                overrun++;
        }
 
-       alarm->node.expires = ktime_add(alarm->node.expires, interval);
+       alarm->node.expires = ktime_add_safe(alarm->node.expires, interval);
        return overrun;
 }
 EXPORT_SYMBOL_GPL(alarm_forward);
@@ -660,13 +660,21 @@ static int alarm_timer_set(struct k_itimer *timr, int flags,
 
        /* start the timer */
        timr->it.alarm.interval = timespec64_to_ktime(new_setting->it_interval);
+
+       /*
+        * Rate limit to the tick as a hot fix to prevent DOS. Will be
+        * mopped up later.
+        */
+       if (timr->it.alarm.interval < TICK_NSEC)
+               timr->it.alarm.interval = TICK_NSEC;
+
        exp = timespec64_to_ktime(new_setting->it_value);
        /* Convert (if necessary) to absolute time */
        if (flags != TIMER_ABSTIME) {
                ktime_t now;
 
                now = alarm_bases[timr->it.alarm.alarmtimer.type].gettime();
-               exp = ktime_add(now, exp);
+               exp = ktime_add_safe(now, exp);
        }
 
        alarm_start(&timr->it.alarm.alarmtimer, exp);