Re: [kernel-hardening] Re: [PATCH] checkpatch: Add ability to find bad uses of vsprintf %p<foo> extensions

[Kees Cook]

On Tue, Feb 28, 2017 at 4:06 PM, Andrew Morton
<akpm@xxxxxxxxxxxxxxxxxxxx> wrote:
> On Mon, 27 Feb 2017 12:54:55 -0800 Joe Perches <joe@xxxxxxxxxxx> wrote:
>
>> %pK was at least once misused at %pk in an out-of-tree module.
>> This lead to some security concerns.  Add the ability to track
>> single and multiple line statements for misuses of %p<foo>.
>
> Should we also do this?

Ah yes, good idea. Maybe "...when adding/removing new conversion..." ?

-Kees

>
> --- a/lib/vsprintf.c~checkpatch-add-ability-to-find-bad-uses-of-vsprintf-%pfoo-extensions-fix
> +++ a/lib/vsprintf.c
> @@ -1477,6 +1477,9 @@ int kptr_restrict __read_mostly;
>   * by an extra set of alphanumeric characters that are extended format
>   * specifiers.
>   *
> + * Please update scripts/checkpatch.pl when adding new conversion characters.
> + * (search for "check for vsprintf extension").
> + *
>   * Right now we handle:
>   *
>   * - 'F' For symbolic function descriptor pointers with offset
> _
>



-- 
Kees Cook
Pixel Security