Re: [PATCH] leds: mt6370: Annotate struct mt6370_priv with __counted_by

["Gustavo A. R. Silva" <gustavo@embeddedor.com>]

On 9/15/23 14:10, Kees Cook wrote:
> Prepare for the coming implementation by GCC and Clang of the __counted_by
> attribute. Flexible array members annotated with __counted_by can have
> their accesses bounds-checked at run-time checking via CONFIG_UBSAN_BOUNDS
> (for array indexing) and CONFIG_FORTIFY_SOURCE (for strcpy/memcpy-family
> functions).
> 
> As found with Coccinelle[1], add __counted_by for struct mt6370_priv.
> 
> [1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci
> 
> Cc: Pavel Machek <pavel@ucw.cz>
> Cc: Lee Jones <lee@kernel.org>
> Cc: Matthias Brugger <matthias.bgg@gmail.com>
> Cc: AngeloGioacchino Del Regno <angelogioacchino.delregno@collabora.com>
> Cc: Alice Chen <alice_chen@richtek.com>
> Cc: Jacek Anaszewski <jacek.anaszewski@gmail.com>
> Cc: ChiYuan Huang <cy_huang@richtek.com>
> Cc: ChiaEn Wu <chiaen_wu@richtek.com>
> Cc: kernel test robot <lkp@intel.com>
> Cc: linux-leds@vger.kernel.org
> Cc: linux-arm-kernel@lists.infradead.org
> Cc: linux-mediatek@lists.infradead.org
> Signed-off-by: Kees Cook <keescook@chromium.org>

Reviewed-by: Gustavo A. R. Silva <gustavoars@kernel.org>

Thanks
-- 
Gustavo

> ---
>   drivers/leds/flash/leds-mt6370-flash.c | 2 +-
>   drivers/leds/rgb/leds-mt6370-rgb.c     | 2 +-
>   2 files changed, 2 insertions(+), 2 deletions(-)
> 
> diff --git a/drivers/leds/flash/leds-mt6370-flash.c b/drivers/leds/flash/leds-mt6370-flash.c
> index 931067c8a75f..912d9d622320 100644
> --- a/drivers/leds/flash/leds-mt6370-flash.c
> +++ b/drivers/leds/flash/leds-mt6370-flash.c
> @@ -81,7 +81,7 @@ struct mt6370_priv {
>   	unsigned int fled_torch_used;
>   	unsigned int leds_active;
>   	unsigned int leds_count;
> -	struct mt6370_led leds[];
> +	struct mt6370_led leds[] __counted_by(leds_count);
>   };
>   
>   static int mt6370_torch_brightness_set(struct led_classdev *lcdev, enum led_brightness level)
> diff --git a/drivers/leds/rgb/leds-mt6370-rgb.c b/drivers/leds/rgb/leds-mt6370-rgb.c
> index bb62431efe83..448d0da11848 100644
> --- a/drivers/leds/rgb/leds-mt6370-rgb.c
> +++ b/drivers/leds/rgb/leds-mt6370-rgb.c
> @@ -153,7 +153,7 @@ struct mt6370_priv {
>   	const struct mt6370_pdata *pdata;
>   	unsigned int leds_count;
>   	unsigned int leds_active;
> -	struct mt6370_led leds[];
> +	struct mt6370_led leds[] __counted_by(leds_count);
>   };
>   
>   static const struct reg_field common_reg_fields[F_MAX_FIELDS] = {