linux/kernel/time
Thomas Gleixner 5f936e19cc alarmtimer: Prevent overflow for relative nanosleep
Air Icy reported:

  UBSAN: Undefined behaviour in kernel/time/alarmtimer.c:811:7
  signed integer overflow:
  1529859276030040771 + 9223372036854775807 cannot be represented in type 'long long int'
  Call Trace:
   alarm_timer_nsleep+0x44c/0x510 kernel/time/alarmtimer.c:811
   __do_sys_clock_nanosleep kernel/time/posix-timers.c:1235 [inline]
   __se_sys_clock_nanosleep kernel/time/posix-timers.c:1213 [inline]
   __x64_sys_clock_nanosleep+0x326/0x4e0 kernel/time/posix-timers.c:1213
   do_syscall_64+0xb8/0x3a0 arch/x86/entry/common.c:290

alarm_timer_nsleep() uses ktime_add() to add the current time and the
relative expiry value. ktime_add() has no sanity checks so the addition
can overflow when the relative timeout is large enough.

Use ktime_add_safe() which has the necessary sanity checks in place and
limits the result to the valid range.

Fixes: 9a7adcf5c6 ("timers: Posix interface for alarm-timers")
Reported-by: Team OWL337 <icytxw@gmail.com>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Cc: John Stultz <john.stultz@linaro.org>
Link: https://lkml.kernel.org/r/alpine.DEB.2.21.1807020926360.1595@nanos.tec.linutronix.de
2018-07-02 11:33:26 +02:00
..
alarmtimer.c alarmtimer: Prevent overflow for relative nanosleep 2018-07-02 11:33:26 +02:00
clockevents.c clockevents: Retry programming min delta up to 10 times 2017-10-19 16:29:15 +02:00
clocksource.c clocksource: Move inline keyword to the beginning of function declarations 2018-05-16 22:21:32 +02:00
hrtimer.c Merge branch 'linus' into timers/2038 2018-05-19 13:55:40 +02:00
itimer.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
jiffies.c jiffies: Revert bogus conversion of NSEC_PER_SEC to TICK_NSEC 2017-03-07 11:03:28 +01:00
Kconfig sched/isolation: Eliminate NO_HZ_FULL_ALL 2018-02-15 15:40:37 -08:00
Makefile License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
ntp_internal.h Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2017-11-13 17:56:58 -08:00
ntp.c timekeeping: Use ktime_get_real_ts64() instead of getnstimeofday64() 2018-06-19 09:56:26 +02:00
posix-clock.c vfs: do bulk POLL* -> EPOLL* replacement 2018-02-11 14:34:03 -08:00
posix-cpu-timers.c posix-timers: Sanitize overrun handling 2018-07-02 11:33:25 +02:00
posix-stubs.c posix-timers: Use new ktime_get_*_ts64() helpers 2018-06-19 09:56:27 +02:00
posix-timers.c posix-timers: Sanitize overrun handling 2018-07-02 11:33:25 +02:00
posix-timers.h posix-timers: Make forward callback return s64 2018-07-02 11:33:25 +02:00
sched_clock.c timers, sched_clock: Update timeout for clock wrap 2017-03-23 12:30:27 -07:00
test_udelay.c
tick-broadcast-hrtimer.c License cleanup: add SPDX GPL-2.0 license identifier to files with no license 2017-11-02 11:10:55 +01:00
tick-broadcast.c tick/broadcast: Use for_each_cpu() specially on UP kernels 2018-05-15 22:45:54 +02:00
tick-common.c Power management updates for 4.18-rc1 2018-06-05 09:38:39 -07:00
tick-internal.h Revert: Unify CLOCK_MONOTONIC and CLOCK_BOOTTIME 2018-04-26 14:53:32 +02:00
tick-oneshot.c clockevents: Fix kernel messages split across multiple lines 2018-04-17 17:18:04 +02:00
tick-sched.c Revert: Unify CLOCK_MONOTONIC and CLOCK_BOOTTIME 2018-04-26 14:53:32 +02:00
tick-sched.h nohz: Gather tick_sched booleans under a common flag field 2018-04-09 11:54:57 +02:00
time.c time: Enable get/put_compat_itimerspec64 always 2018-06-24 14:39:47 +02:00
timeconst.bc time: Introduce jiffies64_to_nsecs() 2017-02-01 09:13:45 +01:00
timeconv.c
timecounter.c clocksource: Use a plain u64 instead of cycle_t 2016-12-25 11:04:12 +01:00
timekeeping_debug.c PM / timekeeping: Print debug messages when requested 2017-07-23 00:03:43 +02:00
timekeeping_internal.h kdb: use __ktime_get_real_seconds instead of __current_kernel_time 2018-01-25 08:40:18 -06:00
timekeeping.c timekeeping: Use ktime_get_real_ts64() instead of getnstimeofday64() 2018-06-19 09:56:26 +02:00
timekeeping.h Revert: Unify CLOCK_MONOTONIC and CLOCK_BOOTTIME 2018-04-26 14:53:32 +02:00
timer_list.c Merge branch 'timers-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip 2018-06-04 20:27:54 -07:00
timer.c timers: Adjust a kernel-doc comment 2018-05-13 15:55:43 +02:00