Re: [PATCH v5 26/39] x86: Introduce userspace API for shadow stack

[Kees Cook]

On Thu, Jan 19, 2023 at 01:23:04PM -0800, Rick Edgecombe wrote:
> From: "Kirill A. Shutemov" <kirill.shutemov@xxxxxxxxxxxxxxx>
> 
> Add three new arch_prctl() handles:
> 
>  - ARCH_SHSTK_ENABLE/DISABLE enables or disables the specified
>    feature. Returns 0 on success or an error.
> 
>  - ARCH_SHSTK_LOCK prevents future disabling or enabling of the
>    specified feature. Returns 0 on success or an error
> 
> The features are handled per-thread and inherited over fork(2)/clone(2),
> but reset on exec().
> 
> This is preparation patch. It does not implement any features.
> 
> Tested-by: Pengfei Xu <pengfei.xu@xxxxxxxxx>
> Tested-by: John Allen <john.allen@xxxxxxx>
> Signed-off-by: Kirill A. Shutemov <kirill.shutemov@xxxxxxxxxxxxxxx>

Reviewed-by: Kees Cook <keescook@xxxxxxxxxxxx>

-- 
Kees Cook