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Subject: Re: [PATCH v6 3/8] sysctl: Warn when a clamped sysctl parameter is
 set out of range
To: Kees Cook <keescook@chromium.org>
Cc: "Luis R. Rodriguez" <mcgrof@kernel.org>,
        Andrew Morton <akpm@linux-foundation.org>,
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From: Waiman Long <longman@redhat.com>
Organization: Red Hat
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Date: Tue, 1 May 2018 09:41:03 -0400
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On 04/30/2018 06:40 PM, Kees Cook wrote:
> I like this series overall, thanks! No objections from me. One thing I
> noted, though:
>
> On Fri, Apr 27, 2018 at 2:00 PM, Waiman Long <longman@redhat.com> wrote:
>>                 if (param->min && *param->min > val) {
>>                         if (clamp) {
>>                                 val = *param->min;
>> +                               clamped = true;
>>                         } else {
>>                                 return -EINVAL;
>>                         }
> This appears as a common bit of logic in many places in the series. It
> seems like it'd make sense to make this a helper of some kind?
>
> -Kees
>
We can't have an inline helper function because the types are different.
We may be able to use a helper macro, but helper macro like that may be
not well accepted by the kernel community.

Cheers,
Longman