Linux kernel mirror (for testing)
git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git
kernel
os
linux
Merge branch 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull timer fixes from Thomas Gleixner:
"Three fixlets for timers:
- Two hot-fixes for the alarmtimer based posix timers, which prevent
a nasty DOS by self rescheduling timers. The proper cleanup of that
mess is queued for 4.13
- Make a function static"
* 'timers-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
tick/broadcast: Make tick_broadcast_setup_oneshot() static
alarmtimer: Rate limit periodic intervals
alarmtimer: Prevent overflow of relative timers
+14
-6
+11
-3
kernel/time/alarmtimer.c
+11
-3
kernel/time/alarmtimer.c
···
387
387
{
388
388
struct alarm_base *base = &alarm_bases[alarm->type];
389
389
390
-
start = ktime_add(start, base->gettime());
390
+
start = ktime_add_safe(start, base->gettime());
391
391
alarm_start(alarm, start);
392
392
}
393
393
EXPORT_SYMBOL_GPL(alarm_start_relative);
···
475
475
overrun++;
476
476
}
477
477
478
-
alarm->node.expires = ktime_add(alarm->node.expires, interval);
478
+
alarm->node.expires = ktime_add_safe(alarm->node.expires, interval);
479
479
return overrun;
480
480
}
481
481
EXPORT_SYMBOL_GPL(alarm_forward);
···
660
660
661
661
/* start the timer */
662
662
timr->it.alarm.interval = timespec64_to_ktime(new_setting->it_interval);
663
+
664
+
/*
665
+
* Rate limit to the tick as a hot fix to prevent DOS. Will be
666
+
* mopped up later.
667
+
*/
668
+
if (timr->it.alarm.interval < TICK_NSEC)
669
+
timr->it.alarm.interval = TICK_NSEC;
670
+
663
671
exp = timespec64_to_ktime(new_setting->it_value);
664
672
/* Convert (if necessary) to absolute time */
665
673
if (flags != TIMER_ABSTIME) {
666
674
ktime_t now;
667
675
668
676
now = alarm_bases[timr->it.alarm.alarmtimer.type].gettime();
669
-
exp = ktime_add(now, exp);
677
+
exp = ktime_add_safe(now, exp);
670
678
}
671
679
672
680
alarm_start(&timr->it.alarm.alarmtimer, exp);
+3
-1
kernel/time/tick-broadcast.c
+3
-1
kernel/time/tick-broadcast.c
···
37
37
static __cacheline_aligned_in_smp DEFINE_RAW_SPINLOCK(tick_broadcast_lock);
38
38
39
39
#ifdef CONFIG_TICK_ONESHOT
40
+
static void tick_broadcast_setup_oneshot(struct clock_event_device *bc);
40
41
static void tick_broadcast_clear_oneshot(int cpu);
41
42
static void tick_resume_broadcast_oneshot(struct clock_event_device *bc);
42
43
#else
44
+
static inline void tick_broadcast_setup_oneshot(struct clock_event_device *bc) { BUG(); }
43
45
static inline void tick_broadcast_clear_oneshot(int cpu) { }
44
46
static inline void tick_resume_broadcast_oneshot(struct clock_event_device *bc) { }
45
47
#endif
···
869
867
/**
870
868
* tick_broadcast_setup_oneshot - setup the broadcast device
871
869
*/
872
-
void tick_broadcast_setup_oneshot(struct clock_event_device *bc)
870
+
static void tick_broadcast_setup_oneshot(struct clock_event_device *bc)
873
871
{
874
872
int cpu = smp_processor_id();
875
873
-2
kernel/time/tick-internal.h
-2
kernel/time/tick-internal.h
···
126
126
127
127
/* Functions related to oneshot broadcasting */
128
128
#if defined(CONFIG_GENERIC_CLOCKEVENTS_BROADCAST) && defined(CONFIG_TICK_ONESHOT)
129
-
extern void tick_broadcast_setup_oneshot(struct clock_event_device *bc);
130
129
extern void tick_broadcast_switch_to_oneshot(void);
131
130
extern void tick_shutdown_broadcast_oneshot(unsigned int cpu);
132
131
extern int tick_broadcast_oneshot_active(void);
···
133
134
bool tick_broadcast_oneshot_available(void);
134
135
extern struct cpumask *tick_get_broadcast_oneshot_mask(void);
135
136
#else /* !(BROADCAST && ONESHOT): */
136
-
static inline void tick_broadcast_setup_oneshot(struct clock_event_device *bc) { BUG(); }
137
137
static inline void tick_broadcast_switch_to_oneshot(void) { }
138
138
static inline void tick_shutdown_broadcast_oneshot(unsigned int cpu) { }
139
139
static inline int tick_broadcast_oneshot_active(void) { return 0; }