This is a note to let you know that I've just added the patch titled
timers: Fix overflow in get_next_timer_interrupt
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:
timers-fix-overflow-in-get_next_timer_interrupt.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 34f41c0316ed52b0b44542491d89278efdaa70e4 Mon Sep 17 00:00:00 2001
From: Matija Glavinic Pecotic <matija.glavinic-pecotic.ext@xxxxxxxxx>
Date: Tue, 1 Aug 2017 09:11:52 +0200
Subject: timers: Fix overflow in get_next_timer_interrupt
From: Matija Glavinic Pecotic <matija.glavinic-pecotic.ext@xxxxxxxxx>
commit 34f41c0316ed52b0b44542491d89278efdaa70e4 upstream.
For e.g. HZ=100, timer being 430 jiffies in the future, and 32 bit
unsigned int, there is an overflow on unsigned int right-hand side
of the expression which results with wrong values being returned.
Type cast the multiplier to 64bit to avoid that issue.
Fixes: 46c8f0b077a8 ("timers: Fix get_next_timer_interrupt() computation")
Signed-off-by: Matija Glavinic Pecotic <matija.glavinic-pecotic.ext@xxxxxxxxx>
Signed-off-by: Thomas Gleixner <tglx@xxxxxxxxxxxxx>
Reviewed-by: Alexander Sverdlin <alexander.sverdlin@xxxxxxxxx>
Cc: khilman@xxxxxxxxxxxx
Cc: akpm@xxxxxxxxxxxxxxxxxxxx
Link: http://lkml.kernel.org/r/a7900f04-2a21-c9fd-67be-ab334d459ee5@xxxxxxxxx
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>
---
kernel/time/timer.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
--- a/kernel/time/timer.c
+++ b/kernel/time/timer.c
@@ -1536,7 +1536,7 @@ u64 get_next_timer_interrupt(unsigned lo
base->is_idle = false;
} else {
if (!is_max_delta)
- expires = basem + (nextevt - basej) * TICK_NSEC;
+ expires = basem + (u64)(nextevt - basej) * TICK_NSEC;
/*
* If we expect to sleep more than a tick, mark the base idle:
*/
Patches currently in stable-queue which might be from matija.glavinic-pecotic.ext@xxxxxxxxx are
queue-4.9/timers-fix-overflow-in-get_next_timer_interrupt.patch