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Date:   Wed, 28 Jul 2021 07:45:47 +0200
From:   Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To:     Kees Cook <keescook@chromium.org>
Cc:     linux-hardening@vger.kernel.org,
        "Gustavo A. R. Silva" <gustavoars@kernel.org>,
        Keith Packard <keithpac@amazon.com>,
        Andrew Morton <akpm@linux-foundation.org>,
        linux-kernel@vger.kernel.org, linux-wireless@vger.kernel.org,
        netdev@vger.kernel.org, dri-devel@lists.freedesktop.org,
        linux-staging@lists.linux.dev, linux-block@vger.kernel.org,
        linux-kbuild@vger.kernel.org, clang-built-linux@googlegroups.com
Subject: Re: [PATCH 24/64] staging: wlan-ng: Use struct_group() for memcpy()
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Message-ID: <YQDvC4CghCazix4w@kroah.com>
References: <20210727205855.411487-1-keescook@chromium.org>
 <20210727205855.411487-25-keescook@chromium.org>
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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>