Re: [PATCH v2 13/63] iommu/amd: Use struct_group() for memcpy() region

Joerg Roedel
2021-08-18T11:34:28Z

On Tue, Aug 17, 2021 at 11:04:43PM -0700, Kees Cook wrote:
> In preparation for FORTIFY_SOURCE performing compile-time and run-time
> field bounds checking for memcpy(), memmove(), and memset(), avoid
> intentionally writing across neighboring fields.
>
> Use struct_group() in struct ivhd_entry around members ext and hidh, so
> they can be referenced together. This will allow memcpy() and sizeof()
> to more easily reason about sizes, improve readability, and avoid future
> warnings about writing beyond the end of ext.
>
> "pahole" shows no size nor member offset changes to struct ivhd_entry.
> "objdump -d" shows no object code changes.
>
> Cc: Joerg Roedel <joro@8bytes.org>
> Cc: Will Deacon <will@kernel.org>
> Cc: iommu@lists.linux-foundation.org
> Signed-off-by: Kees Cook <keescook@chromium.org>

Acked-by: Joerg Roedel <jroedel@suse.de>