Re: [PATCH 24/64] staging: wlan-ng: Use struct_group() for memcpy() region

Greg Kroah-Hartman
2021-07-28T05:45:53Z

On Tue, Jul 27, 2021 at 01:58:15PM -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 hfa384x_tx_frame around members
> frame_control, duration_id, address[1-4], and sequence_control, 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 frame_control.
>
> "pahole" shows no size nor member offset changes to struct
> hfa384x_tx_frame. "objdump -d" shows no meaningful object code changes
> (i.e. only source line number induced differences.)
>
> Signed-off-by: Kees Cook <keescook@chromium.org>
> ---
> drivers/staging/wlan-ng/hfa384x.h | 16 +++++++++-------
> drivers/staging/wlan-ng/hfa384x_usb.c | 4 +++-
> 2 files changed, 12 insertions(+), 8 deletions(-)

Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>