Date: Mon, 7 Dec 2015 21:15:45 +0100 (CET)
From: Thomas Gleixner <tglx@linutronix.de>
To: John Stultz <john.stultz@linaro.org>
cc: Richard Cochran <richardcochran@gmail.com>,
        Sasha Levin <sasha.levin@oracle.com>,
        lkml <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH] time: verify time values in adjtimex ADJ_SETOFFSET to
 avoid overflow
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On Mon, 7 Dec 2015, John Stultz wrote:

> On Sun, Dec 6, 2015 at 2:11 PM, Richard Cochran
> <richardcochran@gmail.com> wrote:
> > The overflow is a latent problem, and the patch should:
> >
> > 1. return error in case (txc->time.tv_usec >= USEC_PER_SEC)
> > 2. remove the redundant test in timekeeping_inject_offset.
> 
> So we probably want to keep the check in timekeeping_inject_offset()
> since there can be other users as well of that function.
> 
> But its probably cleanest to add a check in ntp_validate_timex()
> instead of where this patch does it.

So instead of open coding the checks on both sites, can we please have
an inline function with proper comments why time.tv_sec can be
negative, something like adjtimex_timeval_is_valid() or such.

Thanks,

	tglx


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