Subject: Re: [PATCH][RESEND] sata_fsl: Use struct_group() for memcpy() region
To:     Kees Cook <keescook@chromium.org>
Cc:     linux-ide@vger.kernel.org,
        Damien Le Moal <damien.lemoal@opensource.wdc.com>,
        linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org
References: <20220112220652.3952944-1-keescook@chromium.org>
From:   Jens Axboe <axboe@kernel.dk>
Message-ID: <df3eefdc-d8d1-48fa-f5f7-9c2f2382842b@kernel.dk>
Date:   Wed, 12 Jan 2022 15:23:40 -0700
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On 1/12/22 3:06 PM, 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 command_desc around members acmd and fill,
> so they can be referenced together. This will allow memset(), memcpy(),
> and sizeof() to more easily reason about sizes, improve readability,
> and avoid future warnings about writing beyond the end of acmd:
> 
> In function 'fortify_memset_chk',
>     inlined from 'sata_fsl_qc_prep' at drivers/ata/sata_fsl.c:534:3:
> ./include/linux/fortify-string.h:199:4: warning: call to '__write_overflow_field' declared with attribute warning: detected write beyond size of field (1st parameter); maybe use struct_group()? [-Wattribute-warning]
>   199 |    __write_overflow_field();
>       |    ^~~~~~~~~~~~~~~~~~~~~~~~
> 
> Cc: Jens Axboe <axboe@kernel.dk>
> Cc: linux-ide@vger.kernel.org
> Signed-off-by: Kees Cook <keescook@chromium.org>
> ---
> Jens, can you take (or Ack) this? It's a dependency for the FORTIFY_SOURCE
> improvements that are close to being finished. :)

I don't maintain libata anymore, so Damien is the guy to nudge ;-)

-- 
Jens Axboe