Re: [PATCH 11/21] dmaengine: st_fdma: Annotate struct st_fdma_desc 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 st_fdma_desc.
>
> [1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci
>
> Cc: Vinod Koul <vkoul@xxxxxxxxxx>
> Cc: Patrice Chotard <patrice.chotard@xxxxxxxxxxx>
> 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/st_fdma.h | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/dma/st_fdma.h b/drivers/dma/st_fdma.h
> index fa15b97a3bab..f296412e96b6 100644
> --- a/drivers/dma/st_fdma.h
> +++ b/drivers/dma/st_fdma.h
> @@ -97,7 +97,7 @@ struct st_fdma_desc {
>   	struct st_fdma_chan *fchan;
>   	bool iscyclic;
>   	unsigned int n_nodes;
> -	struct st_fdma_sw_node node[];
> +	struct st_fdma_sw_node node[] __counted_by(n_nodes);
>   };
>   
>   enum st_fdma_type {