Re: [PATCH 01/21] dmaengine: apple-admac: Annotate struct admac_data with __counted_by

[Gustavo A. R. Silva]

On 8/17/23 17:58, 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 admac_data.
>
> [1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci
>
> Cc: Vinod Koul <vkoul@xxxxxxxxxx>
> Cc: Hector Martin <marcan@xxxxxxxxx>
> Cc: Sven Peter <sven@xxxxxxxxxxxxx>
> Cc: Alyssa Rosenzweig <alyssa@xxxxxxxxxxxxx>
> Cc: asahi@xxxxxxxxxxxxxxx
> Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
> Cc: dmaengine@xxxxxxxxxxxxxxx
> Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>

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

Thanks
--
Gustavo

> ---
>   drivers/dma/apple-admac.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/dma/apple-admac.c b/drivers/dma/apple-admac.c
> index 3af795635c5c..ff46260b6ebc 100644
> --- a/drivers/dma/apple-admac.c
> +++ b/drivers/dma/apple-admac.c
> @@ -128,7 +128,7 @@ struct admac_data {
>   	int irq;
>   	int irq_index;
>   	int nchannels;
> -	struct admac_chan channels[];
> +	struct admac_chan channels[] __counted_by(nchannels);
>   };
>   
>   struct admac_tx {