[SRU][Trusty][Xenial][Bionic][PATCH 0/1] Fix for CVE-2018-12896

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APPLIED/cmnt: [SRU][Xenial][PATCH v2 1/1] posix-timers: Sanitize overrun handling

Khaled Elmously
Applied, with the indentation fix that Kleber pointed out.


On 2018-11-29 01:42:41 , Khalid Elmously wrote:

> From: Thomas Gleixner <[hidden email]>
>
> The posix timer overrun handling is broken because the forwarding functions
> can return a huge number of overruns which does not fit in an int. As a
> consequence timer_getoverrun(2) and siginfo::si_overrun can turn into
> random number generators.
>
> The k_clock::timer_forward() callbacks return a 64 bit value now. Make
> k_itimer::ti_overrun[_last] 64bit as well, so the kernel internal
> accounting is correct. 3Remove the temporary (int) casts.
>
> Add a helper function which clamps the overrun value returned to user space
> via timer_getoverrun(2) or siginfo::si_overrun limited to a positive value
> between 0 and INT_MAX. INT_MAX is an indicator for user space that the
> overrun value has been clamped.
>
> Reported-by: Team OWL337 <[hidden email]>
> Signed-off-by: Thomas Gleixner <[hidden email]>
> Acked-by: John Stultz <[hidden email]>
> Cc: Peter Zijlstra <[hidden email]>
> Cc: Michael Kerrisk <[hidden email]>
> Link: https://lkml.kernel.org/r/20180626132705.018623573@...
> (backported from commit 78c9c4dfbf8c04883941445a195276bb4bb92c76)
> [kmously: Mostly context adjustments or adjusting for slightly refactored
> code. A cosmetic change from the original (changing '-1' to
> '-1LL') was dropped because it's not applicable ]
> Signed-off-by: Khalid Elmously <[hidden email]>
> ---
>  include/linux/posix-timers.h   |  4 ++--
>  kernel/time/posix-cpu-timers.c |  2 +-
>  kernel/time/posix-timers.c     | 23 ++++++++++++++++-------
>  3 files changed, 19 insertions(+), 10 deletions(-)
>
> diff --git a/include/linux/posix-timers.h b/include/linux/posix-timers.h
> index 907f3fd191ac..3e28a1a8d823 100644
> --- a/include/linux/posix-timers.h
> +++ b/include/linux/posix-timers.h
> @@ -65,8 +65,8 @@ struct k_itimer {
>   spinlock_t it_lock;
>   clockid_t it_clock; /* which timer type */
>   timer_t it_id; /* timer id */
> - int it_overrun; /* overrun on pending signal  */
> - int it_overrun_last; /* overrun on last delivered signal */
> + s64 it_overrun; /* overrun on pending signal  */
> + s64 it_overrun_last; /* overrun on last delivered signal */
>   int it_requeue_pending; /* waiting to requeue this timer */
>  #define REQUEUE_PENDING 1
>   int it_sigev_notify; /* notify word of sigevent struct */
> diff --git a/kernel/time/posix-cpu-timers.c b/kernel/time/posix-cpu-timers.c
> index 80016b329d94..8fc68e60c795 100644
> --- a/kernel/time/posix-cpu-timers.c
> +++ b/kernel/time/posix-cpu-timers.c
> @@ -103,7 +103,7 @@ static void bump_cpu_timer(struct k_itimer *timer,
>   continue;
>  
>   timer->it.cpu.expires += incr;
> - timer->it_overrun += 1 << i;
> + timer->it_overrun += 1LL << i;
>   delta -= incr;
>   }
>  }
> diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c
> index fc7c37ad90a0..cb77eeab669f 100644
> --- a/kernel/time/posix-timers.c
> +++ b/kernel/time/posix-timers.c
> @@ -354,6 +354,16 @@ static __init int init_posix_timers(void)
>  }
>  
>  __initcall(init_posix_timers);
> +/*
> + * The siginfo si_overrun field and the return value of timer_getoverrun(2)
> + * are of type int. Clamp the overrun value to INT_MAX
> + */
> +static inline int timer_overrun_to_int(struct k_itimer *timr, int baseval)
> +{
> + s64 sum = timr->it_overrun_last + (s64)baseval;
> +
> + return sum > (s64)INT_MAX ? INT_MAX : (int)sum;
> +}
>  
>  static void schedule_next_timer(struct k_itimer *timr)
>  {
> @@ -362,7 +372,7 @@ static void schedule_next_timer(struct k_itimer *timr)
>   if (timr->it.real.interval.tv64 == 0)
>   return;
>  
> - timr->it_overrun += (unsigned int) hrtimer_forward(timer,
> + timr->it_overrun += hrtimer_forward(timer,
>   timer->base->get_time(),
>   timr->it.real.interval);
>  
> @@ -396,7 +406,7 @@ void do_schedule_next_timer(struct siginfo *info)
>   else
>   schedule_next_timer(timr);
>  
> - info->si_overrun += timr->it_overrun_last;
> + info->si_overrun = timer_overrun_to_int(timr, info->si_overrun);
>   }
>  
>   if (timr)
> @@ -491,8 +501,7 @@ static enum hrtimer_restart posix_timer_fn(struct hrtimer *timer)
>   now = ktime_add(now, kj);
>   }
>  #endif
> - timr->it_overrun += (unsigned int)
> - hrtimer_forward(timer, now,
> + timr->it_overrun += hrtimer_forward(timer, now,
>   timr->it.real.interval);
>   ret = HRTIMER_RESTART;
>   ++timr->it_requeue_pending;
> @@ -633,7 +642,7 @@ SYSCALL_DEFINE3(timer_create, const clockid_t, which_clock,
>   it_id_set = IT_ID_SET;
>   new_timer->it_id = (timer_t) new_timer_id;
>   new_timer->it_clock = which_clock;
> - new_timer->it_overrun = -1;
> + new_timer->it_overrun = -1LL;
>  
>   if (timer_event_spec) {
>   if (copy_from_user(&event, timer_event_spec, sizeof (event))) {
> @@ -762,7 +771,7 @@ common_timer_get(struct k_itimer *timr, struct itimerspec *cur_setting)
>   */
>   if (iv.tv64 && (timr->it_requeue_pending & REQUEUE_PENDING ||
>   timr->it_sigev_notify == SIGEV_NONE))
> - timr->it_overrun += (unsigned int) hrtimer_forward(timer, now, iv);
> + timr->it_overrun += hrtimer_forward(timer, now, iv);
>  
>   remaining = __hrtimer_expires_remaining_adjusted(timer, now);
>   /* Return 0 only, when the timer is expired and not pending */
> @@ -824,7 +833,7 @@ SYSCALL_DEFINE1(timer_getoverrun, timer_t, timer_id)
>   if (!timr)
>   return -EINVAL;
>  
> - overrun = timr->it_overrun_last;
> + overrun = timer_overrun_to_int(timr, 0);
>   unlock_timer(timr, flags);
>  
>   return overrun;
> --
> 2.17.1
>

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APPLIED: [SRU][Bionic][PATCH 1/1] posix-timers: Sanitize overrun handling

Khaled Elmously
In reply to this post by Khaled Elmously
On 2018-11-27 00:23:16 , Khalid Elmously wrote:

> From: Thomas Gleixner <[hidden email]>
>
> CVE-2018-12896
>
> The posix timer overrun handling is broken because the forwarding functions
> can return a huge number of overruns which does not fit in an int. As a
> consequence timer_getoverrun(2) and siginfo::si_overrun can turn into
> random number generators.
>
> The k_clock::timer_forward() callbacks return a 64 bit value now. Make
> k_itimer::ti_overrun[_last] 64bit as well, so the kernel internal
> accounting is correct. 3Remove the temporary (int) casts.
>
> Add a helper function which clamps the overrun value returned to user space
> via timer_getoverrun(2) or siginfo::si_overrun limited to a positive value
> between 0 and INT_MAX. INT_MAX is an indicator for user space that the
> overrun value has been clamped.
>
> Reported-by: Team OWL337 <[hidden email]>
> Signed-off-by: Thomas Gleixner <[hidden email]>
> Acked-by: John Stultz <[hidden email]>
> Cc: Peter Zijlstra <[hidden email]>
> Cc: Michael Kerrisk <[hidden email]>
> Link: https://lkml.kernel.org/r/20180626132705.018623573@...
> (cherry picked from commit 78c9c4dfbf8c04883941445a195276bb4bb92c76)
> Signed-off-by: Khalid Elmously <[hidden email]>
> ---
>  include/linux/posix-timers.h   |  4 ++--
>  kernel/time/posix-cpu-timers.c |  2 +-
>  kernel/time/posix-timers.c     | 29 +++++++++++++++++++----------
>  3 files changed, 22 insertions(+), 13 deletions(-)
>
> diff --git a/include/linux/posix-timers.h b/include/linux/posix-timers.h
> index 672c4f32311e..437a539898ae 100644
> --- a/include/linux/posix-timers.h
> +++ b/include/linux/posix-timers.h
> @@ -82,8 +82,8 @@ struct k_itimer {
>   clockid_t it_clock;
>   timer_t it_id;
>   int it_active;
> - int it_overrun;
> - int it_overrun_last;
> + s64 it_overrun;
> + s64 it_overrun_last;
>   int it_requeue_pending;
>   int it_sigev_notify;
>   ktime_t it_interval;
> diff --git a/kernel/time/posix-cpu-timers.c b/kernel/time/posix-cpu-timers.c
> index 1f27887aa194..0f5f019c6645 100644
> --- a/kernel/time/posix-cpu-timers.c
> +++ b/kernel/time/posix-cpu-timers.c
> @@ -84,7 +84,7 @@ static void bump_cpu_timer(struct k_itimer *timer, u64 now)
>   continue;
>  
>   timer->it.cpu.expires += incr;
> - timer->it_overrun += 1 << i;
> + timer->it_overrun += 1LL << i;
>   delta -= incr;
>   }
>  }
> diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c
> index 708992708332..3192a986a483 100644
> --- a/kernel/time/posix-timers.c
> +++ b/kernel/time/posix-timers.c
> @@ -283,6 +283,17 @@ static __init int init_posix_timers(void)
>  }
>  __initcall(init_posix_timers);
>  
> +/*
> + * The siginfo si_overrun field and the return value of timer_getoverrun(2)
> + * are of type int. Clamp the overrun value to INT_MAX
> + */
> +static inline int timer_overrun_to_int(struct k_itimer *timr, int baseval)
> +{
> + s64 sum = timr->it_overrun_last + (s64)baseval;
> +
> + return sum > (s64)INT_MAX ? INT_MAX : (int)sum;
> +}
> +
>  static void common_hrtimer_rearm(struct k_itimer *timr)
>  {
>   struct hrtimer *timer = &timr->it.real.timer;
> @@ -290,9 +301,8 @@ static void common_hrtimer_rearm(struct k_itimer *timr)
>   if (!timr->it_interval)
>   return;
>  
> - timr->it_overrun += (unsigned int) hrtimer_forward(timer,
> - timer->base->get_time(),
> - timr->it_interval);
> + timr->it_overrun += hrtimer_forward(timer, timer->base->get_time(),
> +    timr->it_interval);
>   hrtimer_restart(timer);
>  }
>  
> @@ -321,10 +331,10 @@ void posixtimer_rearm(struct siginfo *info)
>  
>   timr->it_active = 1;
>   timr->it_overrun_last = timr->it_overrun;
> - timr->it_overrun = -1;
> + timr->it_overrun = -1LL;
>   ++timr->it_requeue_pending;
>  
> - info->si_overrun += timr->it_overrun_last;
> + info->si_overrun = timer_overrun_to_int(timr, info->si_overrun);
>   }
>  
>   unlock_timer(timr, flags);
> @@ -418,9 +428,8 @@ static enum hrtimer_restart posix_timer_fn(struct hrtimer *timer)
>   now = ktime_add(now, kj);
>   }
>  #endif
> - timr->it_overrun += (unsigned int)
> - hrtimer_forward(timer, now,
> - timr->it_interval);
> + timr->it_overrun += hrtimer_forward(timer, now,
> +    timr->it_interval);
>   ret = HRTIMER_RESTART;
>   ++timr->it_requeue_pending;
>   timr->it_active = 1;
> @@ -524,7 +533,7 @@ static int do_timer_create(clockid_t which_clock, struct sigevent *event,
>   new_timer->it_id = (timer_t) new_timer_id;
>   new_timer->it_clock = which_clock;
>   new_timer->kclock = kc;
> - new_timer->it_overrun = -1;
> + new_timer->it_overrun = -1LL;
>  
>   if (event) {
>   rcu_read_lock();
> @@ -789,7 +798,7 @@ SYSCALL_DEFINE1(timer_getoverrun, timer_t, timer_id)
>   if (!timr)
>   return -EINVAL;
>  
> - overrun = timr->it_overrun_last;
> + overrun = timer_overrun_to_int(timr, 0);
>   unlock_timer(timr, flags);
>  
>   return overrun;
> --
> 2.17.1
>

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Re: APPLIED/cmnt: [SRU][Trusty][PATCH v3 1/1] posix-timers: Sanitize overrun handling

Kleber Souza
In reply to this post by Khaled Elmously
On 12/3/18 8:49 AM, Khaled Elmously wrote:

> Applied, with the indentation fix that Kleber pointed out
>
> On 2018-11-29 01:43:14 , Khalid Elmously wrote:
>> From: Thomas Gleixner <[hidden email]>
>>
>> The posix timer overrun handling is broken because the forwarding functions
>> can return a huge number of overruns which does not fit in an int. As a
>> consequence timer_getoverrun(2) and siginfo::si_overrun can turn into
>> random number generators.
>>
>> The k_clock::timer_forward() callbacks return a 64 bit value now. Make
>> k_itimer::ti_overrun[_last] 64bit as well, so the kernel internal
>> accounting is correct. 3Remove the temporary (int) casts.
>>
>> Add a helper function which clamps the overrun value returned to user space
>> via timer_getoverrun(2) or siginfo::si_overrun limited to a positive value
>> between 0 and INT_MAX. INT_MAX is an indicator for user space that the
>> overrun value has been clamped.
>>
>> Reported-by: Team OWL337 <[hidden email]>
>> Signed-off-by: Thomas Gleixner <[hidden email]>
>> Acked-by: John Stultz <[hidden email]>
>> Cc: Peter Zijlstra <[hidden email]>
>> Cc: Michael Kerrisk <[hidden email]>
>> Link: https://lkml.kernel.org/r/20180626132705.018623573@...
>> (backported from commit 78c9c4dfbf8c04883941445a195276bb4bb92c76)
>> [kmously: Mostly context adjustments or adjusting for slightly refactored
>> code. A cosmetic change from the original (changing '-1' to
>> '-1LL') was dropped because it's not applicable. Also path changes were
>> needed from kernel/time -> kernel ]
>> Signed-off-by: Khalid Elmously <[hidden email]>

I failed to spot that the commit message didn't have the CVE reference
as required. I have amended the commit to fix it.


Thanks,

Kleber


>> ---
>>  include/linux/posix-timers.h |  4 ++--
>>  kernel/posix-cpu-timers.c    |  2 +-
>>  kernel/posix-timers.c        | 23 ++++++++++++++++-------
>>  3 files changed, 19 insertions(+), 10 deletions(-)
>>
>> diff --git a/include/linux/posix-timers.h b/include/linux/posix-timers.h
>> index 907f3fd191ac..3e28a1a8d823 100644
>> --- a/include/linux/posix-timers.h
>> +++ b/include/linux/posix-timers.h
>> @@ -65,8 +65,8 @@ struct k_itimer {
>>   spinlock_t it_lock;
>>   clockid_t it_clock; /* which timer type */
>>   timer_t it_id; /* timer id */
>> - int it_overrun; /* overrun on pending signal  */
>> - int it_overrun_last; /* overrun on last delivered signal */
>> + s64 it_overrun; /* overrun on pending signal  */
>> + s64 it_overrun_last; /* overrun on last delivered signal */
>>   int it_requeue_pending; /* waiting to requeue this timer */
>>  #define REQUEUE_PENDING 1
>>   int it_sigev_notify; /* notify word of sigevent struct */
>> diff --git a/kernel/posix-cpu-timers.c b/kernel/posix-cpu-timers.c
>> index c7f31aa272f7..bd2f746e837c 100644
>> --- a/kernel/posix-cpu-timers.c
>> +++ b/kernel/posix-cpu-timers.c
>> @@ -103,7 +103,7 @@ static void bump_cpu_timer(struct k_itimer *timer,
>>   continue;
>>  
>>   timer->it.cpu.expires += incr;
>> - timer->it_overrun += 1 << i;
>> + timer->it_overrun += 1LL << i;
>>   delta -= incr;
>>   }
>>  }
>> diff --git a/kernel/posix-timers.c b/kernel/posix-timers.c
>> index 26b910462a0c..832a142ea556 100644
>> --- a/kernel/posix-timers.c
>> +++ b/kernel/posix-timers.c
>> @@ -345,6 +345,16 @@ static __init int init_posix_timers(void)
>>  }
>>  
>>  __initcall(init_posix_timers);
>> +/*
>> + * The siginfo si_overrun field and the return value of timer_getoverrun(2)
>> + * are of type int. Clamp the overrun value to INT_MAX
>> + */
>> +static inline int timer_overrun_to_int(struct k_itimer *timr, int baseval)
>> +{
>> + s64 sum = timr->it_overrun_last + (s64)baseval;
>> +
>> + return sum > (s64)INT_MAX ? INT_MAX : (int)sum;
>> +}
>>  
>>  static void schedule_next_timer(struct k_itimer *timr)
>>  {
>> @@ -353,7 +363,7 @@ static void schedule_next_timer(struct k_itimer *timr)
>>   if (timr->it.real.interval.tv64 == 0)
>>   return;
>>  
>> - timr->it_overrun += (unsigned int) hrtimer_forward(timer,
>> + timr->it_overrun += hrtimer_forward(timer,
>>   timer->base->get_time(),
>>   timr->it.real.interval);
>>  
>> @@ -387,7 +397,7 @@ void do_schedule_next_timer(struct siginfo *info)
>>   else
>>   schedule_next_timer(timr);
>>  
>> - info->si_overrun += timr->it_overrun_last;
>> + info->si_overrun = timer_overrun_to_int(timr, info->si_overrun);
>>   }
>>  
>>   if (timr)
>> @@ -482,8 +492,7 @@ static enum hrtimer_restart posix_timer_fn(struct hrtimer *timer)
>>   now = ktime_add(now, kj);
>>   }
>>  #endif
>> - timr->it_overrun += (unsigned int)
>> - hrtimer_forward(timer, now,
>> + timr->it_overrun += hrtimer_forward(timer, now,
>>   timr->it.real.interval);
>>   ret = HRTIMER_RESTART;
>>   ++timr->it_requeue_pending;
>> @@ -624,7 +633,7 @@ SYSCALL_DEFINE3(timer_create, const clockid_t, which_clock,
>>   it_id_set = IT_ID_SET;
>>   new_timer->it_id = (timer_t) new_timer_id;
>>   new_timer->it_clock = which_clock;
>> - new_timer->it_overrun = -1;
>> + new_timer->it_overrun = -1LL;
>>  
>>   if (timer_event_spec) {
>>   if (copy_from_user(&event, timer_event_spec, sizeof (event))) {
>> @@ -754,7 +763,7 @@ common_timer_get(struct k_itimer *timr, struct itimerspec *cur_setting)
>>   */
>>   if (iv.tv64 && (timr->it_requeue_pending & REQUEUE_PENDING ||
>>      (timr->it_sigev_notify & ~SIGEV_THREAD_ID) == SIGEV_NONE))
>> - timr->it_overrun += (unsigned int) hrtimer_forward(timer, now, iv);
>> + timr->it_overrun += hrtimer_forward(timer, now, iv);
>>  
>>   remaining = ktime_sub(hrtimer_get_expires(timer), now);
>>   /* Return 0 only, when the timer is expired and not pending */
>> @@ -816,7 +825,7 @@ SYSCALL_DEFINE1(timer_getoverrun, timer_t, timer_id)
>>   if (!timr)
>>   return -EINVAL;
>>  
>> - overrun = timr->it_overrun_last;
>> + overrun = timer_overrun_to_int(timr, 0);
>>   unlock_timer(timr, flags);
>>  
>>   return overrun;
>> --
>> 2.17.1
>>


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Re: APPLIED/cmnt: [SRU][Xenial][PATCH v2 1/1] posix-timers: Sanitize overrun handling

Kleber Souza
In reply to this post by Khaled Elmously
On 12/3/18 8:49 AM, Khaled Elmously wrote:

> Applied, with the indentation fix that Kleber pointed out.
>
>
> On 2018-11-29 01:42:41 , Khalid Elmously wrote:
>> From: Thomas Gleixner <[hidden email]>
>>
>> The posix timer overrun handling is broken because the forwarding functions
>> can return a huge number of overruns which does not fit in an int. As a
>> consequence timer_getoverrun(2) and siginfo::si_overrun can turn into
>> random number generators.
>>
>> The k_clock::timer_forward() callbacks return a 64 bit value now. Make
>> k_itimer::ti_overrun[_last] 64bit as well, so the kernel internal
>> accounting is correct. 3Remove the temporary (int) casts.
>>
>> Add a helper function which clamps the overrun value returned to user space
>> via timer_getoverrun(2) or siginfo::si_overrun limited to a positive value
>> between 0 and INT_MAX. INT_MAX is an indicator for user space that the
>> overrun value has been clamped.
>>
>> Reported-by: Team OWL337 <[hidden email]>
>> Signed-off-by: Thomas Gleixner <[hidden email]>
>> Acked-by: John Stultz <[hidden email]>
>> Cc: Peter Zijlstra <[hidden email]>
>> Cc: Michael Kerrisk <[hidden email]>
>> Link: https://lkml.kernel.org/r/20180626132705.018623573@...
>> (backported from commit 78c9c4dfbf8c04883941445a195276bb4bb92c76)
>> [kmously: Mostly context adjustments or adjusting for slightly refactored
>> code. A cosmetic change from the original (changing '-1' to
>> '-1LL') was dropped because it's not applicable ]
>> Signed-off-by: Khalid Elmously <[hidden email]>
>> ---

The fix for Xenial was also missing the CVE reference, amended the
commit to fix it.


Thanks,

Kleber


>>  include/linux/posix-timers.h   |  4 ++--
>>  kernel/time/posix-cpu-timers.c |  2 +-
>>  kernel/time/posix-timers.c     | 23 ++++++++++++++++-------
>>  3 files changed, 19 insertions(+), 10 deletions(-)
>>
>> diff --git a/include/linux/posix-timers.h b/include/linux/posix-timers.h
>> index 907f3fd191ac..3e28a1a8d823 100644
>> --- a/include/linux/posix-timers.h
>> +++ b/include/linux/posix-timers.h
>> @@ -65,8 +65,8 @@ struct k_itimer {
>>   spinlock_t it_lock;
>>   clockid_t it_clock; /* which timer type */
>>   timer_t it_id; /* timer id */
>> - int it_overrun; /* overrun on pending signal  */
>> - int it_overrun_last; /* overrun on last delivered signal */
>> + s64 it_overrun; /* overrun on pending signal  */
>> + s64 it_overrun_last; /* overrun on last delivered signal */
>>   int it_requeue_pending; /* waiting to requeue this timer */
>>  #define REQUEUE_PENDING 1
>>   int it_sigev_notify; /* notify word of sigevent struct */
>> diff --git a/kernel/time/posix-cpu-timers.c b/kernel/time/posix-cpu-timers.c
>> index 80016b329d94..8fc68e60c795 100644
>> --- a/kernel/time/posix-cpu-timers.c
>> +++ b/kernel/time/posix-cpu-timers.c
>> @@ -103,7 +103,7 @@ static void bump_cpu_timer(struct k_itimer *timer,
>>   continue;
>>  
>>   timer->it.cpu.expires += incr;
>> - timer->it_overrun += 1 << i;
>> + timer->it_overrun += 1LL << i;
>>   delta -= incr;
>>   }
>>  }
>> diff --git a/kernel/time/posix-timers.c b/kernel/time/posix-timers.c
>> index fc7c37ad90a0..cb77eeab669f 100644
>> --- a/kernel/time/posix-timers.c
>> +++ b/kernel/time/posix-timers.c
>> @@ -354,6 +354,16 @@ static __init int init_posix_timers(void)
>>  }
>>  
>>  __initcall(init_posix_timers);
>> +/*
>> + * The siginfo si_overrun field and the return value of timer_getoverrun(2)
>> + * are of type int. Clamp the overrun value to INT_MAX
>> + */
>> +static inline int timer_overrun_to_int(struct k_itimer *timr, int baseval)
>> +{
>> + s64 sum = timr->it_overrun_last + (s64)baseval;
>> +
>> + return sum > (s64)INT_MAX ? INT_MAX : (int)sum;
>> +}
>>  
>>  static void schedule_next_timer(struct k_itimer *timr)
>>  {
>> @@ -362,7 +372,7 @@ static void schedule_next_timer(struct k_itimer *timr)
>>   if (timr->it.real.interval.tv64 == 0)
>>   return;
>>  
>> - timr->it_overrun += (unsigned int) hrtimer_forward(timer,
>> + timr->it_overrun += hrtimer_forward(timer,
>>   timer->base->get_time(),
>>   timr->it.real.interval);
>>  
>> @@ -396,7 +406,7 @@ void do_schedule_next_timer(struct siginfo *info)
>>   else
>>   schedule_next_timer(timr);
>>  
>> - info->si_overrun += timr->it_overrun_last;
>> + info->si_overrun = timer_overrun_to_int(timr, info->si_overrun);
>>   }
>>  
>>   if (timr)
>> @@ -491,8 +501,7 @@ static enum hrtimer_restart posix_timer_fn(struct hrtimer *timer)
>>   now = ktime_add(now, kj);
>>   }
>>  #endif
>> - timr->it_overrun += (unsigned int)
>> - hrtimer_forward(timer, now,
>> + timr->it_overrun += hrtimer_forward(timer, now,
>>   timr->it.real.interval);
>>   ret = HRTIMER_RESTART;
>>   ++timr->it_requeue_pending;
>> @@ -633,7 +642,7 @@ SYSCALL_DEFINE3(timer_create, const clockid_t, which_clock,
>>   it_id_set = IT_ID_SET;
>>   new_timer->it_id = (timer_t) new_timer_id;
>>   new_timer->it_clock = which_clock;
>> - new_timer->it_overrun = -1;
>> + new_timer->it_overrun = -1LL;
>>  
>>   if (timer_event_spec) {
>>   if (copy_from_user(&event, timer_event_spec, sizeof (event))) {
>> @@ -762,7 +771,7 @@ common_timer_get(struct k_itimer *timr, struct itimerspec *cur_setting)
>>   */
>>   if (iv.tv64 && (timr->it_requeue_pending & REQUEUE_PENDING ||
>>   timr->it_sigev_notify == SIGEV_NONE))
>> - timr->it_overrun += (unsigned int) hrtimer_forward(timer, now, iv);
>> + timr->it_overrun += hrtimer_forward(timer, now, iv);
>>  
>>   remaining = __hrtimer_expires_remaining_adjusted(timer, now);
>>   /* Return 0 only, when the timer is expired and not pending */
>> @@ -824,7 +833,7 @@ SYSCALL_DEFINE1(timer_getoverrun, timer_t, timer_id)
>>   if (!timr)
>>   return -EINVAL;
>>  
>> - overrun = timr->it_overrun_last;
>> + overrun = timer_overrun_to_int(timr, 0);
>>   unlock_timer(timr, flags);
>>  
>>   return overrun;
>> --
>> 2.17.1
>>


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