Re: [PATCH 20/21] dmaengine: uniphier-xdmac: Annotate struct uniphier_xdmac_device 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 uniphier_xdmac_device.
>
> [1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci
>
> Cc: Vinod Koul <vkoul@xxxxxxxxxx>
> Cc: Kunihiko Hayashi <hayashi.kunihiko@xxxxxxxxxxxxx>
> Cc: Masami Hiramatsu <mhiramat@xxxxxxxxxx>
> Cc: dmaengine@xxxxxxxxxxxxxxx
> Cc: linux-arm-kernel@xxxxxxxxxxxxxxxxxxx
> Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>

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

Thanks
--
Gustavo

> ---
>   drivers/dma/uniphier-xdmac.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/dma/uniphier-xdmac.c b/drivers/dma/uniphier-xdmac.c
> index dd51522879a7..3a8ee2b173b5 100644
> --- a/drivers/dma/uniphier-xdmac.c
> +++ b/drivers/dma/uniphier-xdmac.c
> @@ -97,7 +97,7 @@ struct uniphier_xdmac_device {
>   	struct dma_device ddev;
>   	void __iomem *reg_base;
>   	int nr_chans;
> -	struct uniphier_xdmac_chan channels[];
> +	struct uniphier_xdmac_chan channels[] __counted_by(nr_chans);
>   };
>   
>   static struct uniphier_xdmac_chan *