Patch "alarmtimer: Fix bug where relative alarm timers were treated as absolute" has been added to the 3.10-stable tree

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This is a note to let you know that I've just added the patch titled

    alarmtimer: Fix bug where relative alarm timers were treated as absolute

to the 3.10-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-fix-bug-where-relative-alarm-timers-were-treated-as-absolute.patch
and it can be found in the queue-3.10 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.


>From 16927776ae757d0d132bdbfabbfe2c498342bd59 Mon Sep 17 00:00:00 2001
From: John Stultz <john.stultz@xxxxxxxxxx>
Date: Mon, 7 Jul 2014 14:06:11 -0700
Subject: alarmtimer: Fix bug where relative alarm timers were treated as absolute

From: John Stultz <john.stultz@xxxxxxxxxx>

commit 16927776ae757d0d132bdbfabbfe2c498342bd59 upstream.

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@xxxxxxxxxx>
Signed-off-by: John Stultz <john.stultz@xxxxxxxxxx>
Cc: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Cc: Ingo Molnar <mingo@xxxxxxxxxx>
Cc: Prarit Bhargava <prarit@xxxxxxxxxx>
Cc: Sharvil Nanavati <sharvil@xxxxxxxxxx>
Link: http://lkml.kernel.org/r/1404767171-6902-1-git-send-email-john.stultz@xxxxxxxxxx
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 kernel/time/alarmtimer.c |   20 ++++++++++++++++++--
 1 file changed, 18 insertions(+), 2 deletions(-)

--- a/kernel/time/alarmtimer.c
+++ b/kernel/time/alarmtimer.c
@@ -540,9 +540,14 @@ static int alarm_timer_set(struct k_itim
 				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);
 
@@ -552,8 +557,16 @@ static int alarm_timer_set(struct k_itim
 
 	/* 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;
 }
 
@@ -685,6 +698,9 @@ static int alarm_timer_nsleep(const cloc
 	if (!alarmtimer_get_rtcdev())
 		return -ENOTSUPP;
 
+	if (flags & ~TIMER_ABSTIME)
+		return -EINVAL;
+
 	if (!capable(CAP_WAKE_ALARM))
 		return -EPERM;
 


Patches currently in stable-queue which might be from john.stultz@xxxxxxxxxx are

queue-3.10/alarmtimer-fix-bug-where-relative-alarm-timers-were-treated-as-absolute.patch
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