This is a note to let you know that I've just added the patch titled alarmtimer: don't rate limit one-shot timers to the 4.9-stable tree which can be found at: http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary The filename of the patch is: alarmtimer-don-t-rate-limit-one-shot-timers.patch and it can be found in the queue-4.9 subdirectory. If you, or anyone else, feels it should not be added to the stable tree, please let <stable@xxxxxxxxxxxxxxx> know about it. >From ghackmann@xxxxxxxxxx Tue Jul 25 10:58:26 2017 From: Greg Hackmann <ghackmann@xxxxxxxxxx> Date: Mon, 24 Jul 2017 10:19:24 -0700 Subject: alarmtimer: don't rate limit one-shot timers To: John Stultz <john.stultz@xxxxxxxxxx>, Thomas Gleixner <tglx@xxxxxxxxxxxxx> Cc: Ben Fennema <fennema@xxxxxxxxxx>, linux-kernel@xxxxxxxxxxxxxxx, Greg Hackmann <ghackmann@xxxxxxxxxx>, stable@xxxxxxxxxxxxxxx Message-ID: <20170724171924.27898-1-ghackmann@xxxxxxxxxx> From: Greg Hackmann <ghackmann@xxxxxxxxxx> Commit ff86bf0c65f1 ("alarmtimer: Rate limit periodic intervals") sets a minimum bound on the alarm timer interval. This minimum bound shouldn't be applied if the interval is 0. Otherwise, one-shot timers will be converted into periodic ones. Fixes: ff86bf0c65f1 ("alarmtimer: Rate limit periodic intervals") Reported-by: Ben Fennema <fennema@xxxxxxxxxx> Signed-off-by: Greg Hackmann <ghackmann@xxxxxxxxxx> Cc: stable@xxxxxxxxxxxxxxx Cc: John Stultz <john.stultz@xxxxxxxxxx> Reviewed-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- kernel/time/alarmtimer.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/kernel/time/alarmtimer.c +++ b/kernel/time/alarmtimer.c @@ -629,7 +629,8 @@ static int alarm_timer_set(struct k_itim * Rate limit to the tick as a hot fix to prevent DOS. Will be * mopped up later. */ - if (ktime_to_ns(timr->it.alarm.interval) < TICK_NSEC) + if (timr->it.alarm.interval.tv64 && + ktime_to_ns(timr->it.alarm.interval) < TICK_NSEC) timr->it.alarm.interval = ktime_set(0, TICK_NSEC); exp = timespec_to_ktime(new_setting->it_value); Patches currently in stable-queue which might be from ghackmann@xxxxxxxxxx are queue-4.9/alarmtimer-don-t-rate-limit-one-shot-timers.patch