linux-kernel - Re: [PATCH] lib/kstrtox.c Stop parsing integer on overflow

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Date:	Wed, 18 Feb 2015 00:20:45 +0100
From:	Richard Weinberger <richard.weinberger@...il.com>
To:	Anshul Garg <aksgarg1989@...il.com>
Cc:	LKML <linux-kernel@...r.kernel.org>, anshul.g@...sung.com,
	Linus Torvalds <torvalds@...ux-foundation.org>
Subject: Re: [PATCH] lib/kstrtox.c Stop parsing integer on overflow

On Mon, Feb 16, 2015 at 7:48 PM, Anshul Garg <aksgarg1989@...il.com> wrote:
> From: Anshul Garg <aksgarg1989@...il.com>
>
> While converting string representation to integer
> break the loop if overflow is detected.
>
> Signed-off-by: Anshul Garg <aksgarg1989@...il.com>
> ---
>  lib/kstrtox.c |    4 +++-
>  1 file changed, 3 insertions(+), 1 deletion(-)
>
> diff --git a/lib/kstrtox.c b/lib/kstrtox.c
> index ec8da78..6f30209 100644
> --- a/lib/kstrtox.c
> +++ b/lib/kstrtox.c
> @@ -70,8 +70,10 @@ unsigned int _parse_integer(const char *s, unsigned int base, unsigned long long
>                  * it in the max base we support (16)
>                  */
>                 if (unlikely(res & (~0ull << 60))) {
> -                       if (res > div_u64(ULLONG_MAX - val, base))
> +                       if (res > div_u64(ULLONG_MAX - val, base)) {
>                                 overflow = 1;
> +                               break;

This changes the behaviour as described at the function description.
Did you double check that all users of that function can deal with that?

> +                       }
>                 }
>                 res = res * base + val;
>                 rv++;
> --
> 1.7.9.5
>
>
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-- 
Thanks,
//richard
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