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Date:   Thu, 8 Jun 2023 19:23:58 +0300
From:   Andy Shevchenko <andriy.shevchenko@linux.intel.com>
To:     Richard Weinberger <richard@nod.at>
Cc:     linux-hardening <linux-hardening@vger.kernel.org>,
        netdev <netdev@vger.kernel.org>,
        linux-kernel <linux-kernel@vger.kernel.org>,
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        John Fastabend <john.fastabend@gmail.com>
Subject: Re: [RFC PATCH 1/1] vsprintf: Warn on integer scanning overflows
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On Thu, Jun 08, 2023 at 06:14:33PM +0200, Richard Weinberger wrote:
> ----- Urspr?ngliche Mail -----
> > Von: "Andy Shevchenko" <andriy.shevchenko@linux.intel.com>
> >>  	if (prefix_chars < max_chars) {
> >>  		rv = _parse_integer_limit(cp, base, &result, max_chars - prefix_chars);
> >> +		WARN_ON_ONCE(rv & KSTRTOX_OVERFLOW);
> > 
> > This seems incorrect. simple_strto*() are okay to overflow. It's by design.
> 
> Is this design decision also known to all users of scanf functions in the kernel?

We have test_scanf.c. Does it miss any test cases? Please add them!

-- 
With Best Regards,
Andy Shevchenko