alarmtimer: Fix bug where relative alarm timers were treated as absolute (16927776) · Commits · 戴 / test

Sharvil noticed with the posix timer_settime interface, using the CLOCK_REALTIME_ALARM or CLOCK_BOOTTIME_ALARM clockid, if the users tried to specify a relative time timer, it would incorrectly be treated as absolute regardless of the state of the flags argument. This patch corrects this, properly checking the absolute/relative flag, as well as adds further error checking that no invalid flag bits are set. Reported-by:

Sharvil Nanavati <sharvil@google.com> Signed-off-by:

John Stultz <john.stultz@linaro.org> Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@kernel.org> Cc: Prarit Bhargava <prarit@redhat.com> Cc: Sharvil Nanavati <sharvil@google.com> Cc: stable <stable@vger.kernel.org> #3.0+ Link: http://lkml.kernel.org/r/1404767171-6902-1-git-send-email-john.stultz@linaro.org Signed-off-by:

Thomas Gleixner <tglx@linutronix.de>

kernel/time/alarmtimer.c

+18 −2

Original line number	Diff line number	Diff line
		@@ -585,9 +585,14 @@ static int alarm_timer_set(struct k_itimer *timr, int flags,
		struct itimerspec *new_setting,
		struct itimerspec *old_setting)
		{
		ktime_t exp;

		if (!rtcdev)
		return -ENOTSUPP;

		if (flags & ~TIMER_ABSTIME)
		return -EINVAL;

		if (old_setting)
		alarm_timer_get(timr, old_setting);

		@@ -597,8 +602,16 @@ static int alarm_timer_set(struct k_itimer *timr, int flags,

		/* start the timer */
		timr->it.alarm.interval = timespec_to_ktime(new_setting->it_interval);
		alarm_start(&timr->it.alarm.alarmtimer,
		timespec_to_ktime(new_setting->it_value));
		exp = timespec_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);
		}

		alarm_start(&timr->it.alarm.alarmtimer, exp);
		return 0;
		}

		@@ -730,6 +743,9 @@ static int alarm_timer_nsleep(const clockid_t which_clock, int flags,
		if (!alarmtimer_get_rtcdev())
		return -ENOTSUPP;

		if (flags & ~TIMER_ABSTIME)
		return -EINVAL;

		if (!capable(CAP_WAKE_ALARM))
		return -EPERM;

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