Re: [PATCH] leds: aw200xx: Annotate struct aw200xx with __counted_by

[Gustavo A. R. Silva]

On 9/15/23 14:09, 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 aw200xx.
>
> [1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci
>
> Cc: Pavel Machek <pavel@xxxxxx>
> Cc: Lee Jones <lee@xxxxxxxxxx>
> Cc: linux-leds@xxxxxxxxxxxxxxx
> Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>

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

Thanks
--
Gustavo

> ---
>   drivers/leds/leds-aw200xx.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/leds/leds-aw200xx.c b/drivers/leds/leds-aw200xx.c
> index 691a743cc9b0..4d517cace3e7 100644
> --- a/drivers/leds/leds-aw200xx.c
> +++ b/drivers/leds/leds-aw200xx.c
> @@ -112,7 +112,7 @@ struct aw200xx {
>   	struct mutex mutex;
>   	u32 num_leds;
>   	u32 display_rows;
> -	struct aw200xx_led leds[];
> +	struct aw200xx_led leds[] __counted_by(num_leds);
>   };
>   
>   static ssize_t dim_show(struct device *dev, struct device_attribute *devattr,