Commit 265b81d2 authored by Richard Larocque's avatar Richard Larocque Committed by John Stultz

alarmtimer: Do not signal SIGEV_NONE timers

Avoids sending a signal to alarm timers created with sigev_notify set to
SIGEV_NONE by checking for that special case in the timeout callback.

The regular posix timers avoid sending signals to SIGEV_NONE timers by
not scheduling any callbacks for them in the first place.  Although it
would be possible to do something similar for alarm timers, it's simpler
to handle this as a special case in the timeout.

Prior to this patch, the alarm timer would ignore the sigev_notify value
and try to deliver signals to the process anyway.  Even worse, the
sanity check for the value of sigev_signo is skipped when SIGEV_NONE was
specified, so the signal number could be bogus.  If sigev_signo was an
unitialized value (as it often would be if SIGEV_NONE is used), then
it's hard to predict which signal will be sent.

Cc: stable@vger.kernel.org
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: Ingo Molnar <mingo@kernel.org>
Cc: Richard Cochran <richardcochran@gmail.com>
Cc: Prarit Bhargava <prarit@redhat.com>
Cc: Sharvil Nanavati <sharvil@google.com>
Signed-off-by: default avatarRichard Larocque <rlarocque@google.com>
Signed-off-by: default avatarJohn Stultz <john.stultz@linaro.org>
parent e86fea76
...@@ -466,8 +466,10 @@ static enum alarmtimer_restart alarm_handle_timer(struct alarm *alarm, ...@@ -466,8 +466,10 @@ static enum alarmtimer_restart alarm_handle_timer(struct alarm *alarm,
{ {
struct k_itimer *ptr = container_of(alarm, struct k_itimer, struct k_itimer *ptr = container_of(alarm, struct k_itimer,
it.alarm.alarmtimer); it.alarm.alarmtimer);
if (posix_timer_event(ptr, 0) != 0) if ((ptr->it_sigev_notify & ~SIGEV_THREAD_ID) != SIGEV_NONE) {
ptr->it_overrun++; if (posix_timer_event(ptr, 0) != 0)
ptr->it_overrun++;
}
/* Re-add periodic timers */ /* Re-add periodic timers */
if (ptr->it.alarm.interval.tv64) { if (ptr->it.alarm.interval.tv64) {
......
Markdown is supported
0%
or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment