Vegard Nossum 979515c564 time: Avoid undefined behaviour in ktime_add_safe() ... I ran into this: ================================================================================ UBSAN: Undefined behaviour in kernel/time/hrtimer.c:310:16 signed integer overflow: 9223372036854775807 + 50000 cannot be represented in type 'long long int' CPU: 2 PID: 4798 Comm: trinity-c2 Not tainted 4.8.0-rc1+ #91 Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS rel-1.9.3-0-ge2fc41e-prebuilt.qemu-project.org 04/01/2014 0000000000000000 ffff88010ce6fb88 ffffffff82344740 0000000041b58ab3 ffffffff84f97a20 ffffffff82344694 ffff88010ce6fbb0 ffff88010ce6fb60 000000000000c350 ffff88010ce6f968 dffffc0000000000 ffffffff857bc320 Call Trace: [<ffffffff82344740>] dump_stack+0xac/0xfc [<ffffffff82344694>] ? _atomic_dec_and_lock+0xc4/0xc4 [<ffffffff8242df78>] ubsan_epilogue+0xd/0x8a [<ffffffff8242e6b4>] handle_overflow+0x202/0x23d [<ffffffff8242e4b2>] ? val_to_string.constprop.6+0x11e/0x11e [<ffffffff8236df71>] ? timerqueue_add+0x151/0x410 [<ffffffff81485c48>] ? hrtimer_start_range_ns+0x3b8/0x1380 [<ffffffff81795631>] ? memset+0x31/0x40 [<ffffffff8242e6fd>] __ubsan_handle_add_overflow+0xe/0x10 [<ffffffff81488ac9>] hrtimer_nanosleep+0x5d9/0x790 [<ffffffff814884f0>] ? hrtimer_init_sleeper+0x80/0x80 [<ffffffff813a9ffb>] ? __might_sleep+0x5b/0x260 [<ffffffff8148be10>] common_nsleep+0x20/0x30 [<ffffffff814906c7>] SyS_clock_nanosleep+0x197/0x210 [<ffffffff81490530>] ? SyS_clock_getres+0x150/0x150 [<ffffffff823c7113>] ? __this_cpu_preempt_check+0x13/0x20 [<ffffffff8162ef60>] ? __context_tracking_exit.part.3+0x30/0x1b0 [<ffffffff81490530>] ? SyS_clock_getres+0x150/0x150 [<ffffffff81007bd3>] do_syscall_64+0x1b3/0x4b0 [<ffffffff845f85aa>] entry_SYSCALL64_slow_path+0x25/0x25 ================================================================================ Add a new ktime_add_unsafe() helper which doesn't check for overflow, but doesn't throw a UBSAN warning when it does overflow either. Cc: Thomas Gleixner <tglx@linutronix.de> Cc: Ingo Molnar <mingo@kernel.org> Cc: Richard Cochran <richardcochran@gmail.com> Cc: Prarit Bhargava <prarit@redhat.com> Signed-off-by: Vegard Nossum <vegard.nossum@oracle.com> Signed-off-by: John Stultz <john.stultz@linaro.org>		2016-08-31 14:43:36 -07:00
..
alarmtimer.c	alarmtimer: Fix comments describing structure fields	2016-06-20 12:47:09 -07:00
clockevents.c	clockevents: Make clockevents_subsys static	2016-07-19 10:48:06 +02:00
clocksource.c	clocksource: Defer override invalidation unless clock is unstable	2016-08-31 14:43:33 -07:00
hrtimer.c	time: Avoid undefined behaviour in ktime_add_safe()	2016-08-31 14:43:36 -07:00
itimer.c
jiffies.c
Kconfig
Makefile
ntp_internal.h
ntp.c
posix-clock.c
posix-cpu-timers.c	posix_cpu_timer: Exit early when process has been reaped	2016-07-11 17:20:12 +02:00
posix-timers.c
sched_clock.c
test_udelay.c	time: Avoid timespec in udelay_test	2016-06-20 12:47:26 -07:00
tick-broadcast-hrtimer.c	tick/broadcast-hrtimer: Set name of the ce_broadcast_hrtimer	2016-07-05 17:02:19 +02:00
tick-broadcast.c
tick-common.c
tick-internal.h	timers: Forward the wheel clock whenever possible	2016-07-07 10:35:11 +02:00
tick-oneshot.c
tick-sched.c	tick/nohz: Optimize nohz idle enter	2016-07-19 13:48:24 +02:00
tick-sched.h	timers/nohz: Convert tick dependency mask to atomic_t	2016-03-29 11:52:11 +02:00
time.c	time: Avoid undefined behaviour in timespec64_add_safe()	2016-08-31 14:43:35 -07:00
timeconst.bc
timeconv.c	time: Add time64_to_tm()	2016-06-20 12:47:15 -07:00
timecounter.c
timekeeping_debug.c	timekeeping: Prints the amounts of time spent during suspend	2016-08-31 14:43:34 -07:00
timekeeping_internal.h
timekeeping.c	timekeeping: Avoid taking lock in NMI path with CONFIG_DEBUG_TIMEKEEPING	2016-08-24 09:34:31 +02:00
timekeeping.h
timer_list.c
timer_stats.c	timer: Avoid using timespec	2016-06-20 12:47:33 -07:00
timer.c	timers: Fix get_next_timer_interrupt() computation	2016-08-09 09:31:55 +02:00