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From:   Bill Wendling <morbo@google.com>
Date:   Mon, 22 May 2023 15:38:09 -0700
Message-ID: <CAGG=3QWFHYnUex4ZUYyMp=JNS9PDLjcagkdLbgTdLQf81Xqp_A@mail.gmail.com>
Subject: Re: [PATCH] lkdtm/bugs: Switch from 1-element array to flexible array
To:     Kees Cook <keescook@chromium.org>
Cc:     Arnd Bergmann <arnd@arndb.de>,
        Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org
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On Mon, May 22, 2023 at 2:30=E2=80=AFPM Kees Cook <keescook@chromium.org> w=
rote:
>
> The testing for ARRAY_BOUNDS just wants an uninstrumented array,
> and the proper flexible array definition is fine for that.
>
> Cc: Arnd Bergmann <arnd@arndb.de>
> Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
> Signed-off-by: Kees Cook <keescook@chromium.org>

Reviewed-by: Bill Wendling <morbo@google.com>

> ---
>  drivers/misc/lkdtm/bugs.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
>
> diff --git a/drivers/misc/lkdtm/bugs.c b/drivers/misc/lkdtm/bugs.c
> index 48821f4c2b21..224f42cdddf2 100644
> --- a/drivers/misc/lkdtm/bugs.c
> +++ b/drivers/misc/lkdtm/bugs.c
> @@ -305,11 +305,10 @@ static void lkdtm_OVERFLOW_UNSIGNED(void)
>         ignored =3D value;
>  }
>
> -/* Intentionally using old-style flex array definition of 1 byte. */
>  struct array_bounds_flex_array {
>         int one;
>         int two;
> -       char data[1];
> +       char data[];
>  };
>
>  struct array_bounds {
> --
> 2.34.1
>