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Date:   Mon, 8 Jul 2019 11:24:59 +0200 (CEST)
From:   Thomas Gleixner <tglx@linutronix.de>
To:     ZhangXiaoxu <zhangxiaoxu5@huawei.com>
cc:     john.stultz@linaro.org, sboyd@kernel.org,
        linux-kernel@vger.kernel.org
Subject: Re: [PATCH] time: Validate the usec before covert to nsec in
 do_adjtimex
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On Mon, 8 Jul 2019, ZhangXiaoxu wrote:

> When covert the usec to nsec, it will multiple 1000, it maybe
> overflow and lead an undefined behavior.
> 
> For example, users may input an negative tv_usec values when
> call adjtimex syscall, then multiple 1000 maybe overflow it
> to a positive and legal number.
> 
> So, we should validate the usec before coverted it to nsec.

That's correct, but the actuall inject function wants to keep the sanity
check,

Thanks,

	tglx