Re: [PATCH v4 38/39] x86/shstk: Add ARCH_SHSTK_UNLOCK

Kees Cook
2022-12-03T02:56:34Z

On Fri, Dec 02, 2022 at 04:36:05PM -0800, Rick Edgecombe wrote:
> From: Mike Rapoport <rppt@linux.ibm.com>
>
> Userspace loaders may lock features before a CRIU restore operation has
> the chance to set them to whatever state is required by the process
> being restored. Allow a way for CRIU to unlock features. Add it as an
> arch_prctl() like the other shadow stack operations, but restrict it being
> called by the ptrace arch_pctl() interface.
>
> Tested-by: Pengfei Xu <pengfei.xu@intel.com>
> Tested-by: John Allen <john.allen@amd.com>
> Signed-off-by: Mike Rapoport <rppt@linux.ibm.com>

Reviewed-by: Kees Cook <keescook@chromium.org>

--
Kees Cook