[PATCH 05/11] time/posix-timers:Convert to the 64bit methods for k_clock callback functions

Baolin Wang baolin.wang at linaro.org
Tue Apr 21 18:36:13 AEST 2015


On 21 April 2015 at 04:48, Thomas Gleixner <tglx at linutronix.de> wrote:

> On Mon, 20 Apr 2015, Baolin Wang wrote:
> >  /* Set clock_realtime */
> >  static int posix_clock_realtime_set(const clockid_t which_clock,
> > -                                 const struct timespec *tp)
> > +                                 const struct timespec64 *tp)
> >  {
> > -     return do_sys_settimeofday(tp, NULL);
> > +     struct timespec ts = timespec64_to_timespec(*tp);
> > +
> > +     return do_sys_settimeofday(&ts, NULL);
>
> Sigh. No. We first provide a proper function for this, which takes a
> timespec64, i.e. do_sys_settimeofday64() instead of having this
> wrapper mess all over the place.
>

Thanks for your comments,but if use do_sys_settimeofday64() here that
will  introduce
a security bug: do_sys_settimeofday contains a capability
check that normally prevents non-root users from setting the time.

With your change, any user can set the system time.

>
> >       /* SIGEV_NONE timers are not queued ! See common_timer_get */
> >       if (((timr->it_sigev_notify & ~SIGEV_THREAD_ID) == SIGEV_NONE)) {
> > diff --git a/kernel/time/timekeeping.h b/kernel/time/timekeeping.h
> > index 1d91416..144af14 100644
> > --- a/kernel/time/timekeeping.h
> > +++ b/kernel/time/timekeeping.h
> > @@ -15,7 +15,7 @@ extern u64 timekeeping_max_deferment(void);
> >  extern int timekeeping_inject_offset(struct timespec *ts);
> >  extern s32 timekeeping_get_tai_offset(void);
> >  extern void timekeeping_set_tai_offset(s32 tai_offset);
> > -extern void timekeeping_clocktai(struct timespec *ts);
> > +extern void timekeeping_clocktai(struct timespec64 *ts);
>
> # git grep timekeeping_clocktai() is your friend.
>
> Thanks,
>
>         tglx
>



-- 
Baolin.wang
Best Regards
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