Re: [PATCH] dmaengine: fsl-edma: Annotate struct struct fsl_edma_engine with __counted_by

[Gustavo A. R. Silva]

On 10/4/23 01:27, 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 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 struct fsl_edma_engine.
>
> Cc: Vinod Koul <vkoul@xxxxxxxxxx>
> Cc: dmaengine@xxxxxxxxxxxxxxx
> Link: https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci [1]
> Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>

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

Thanks
--
Gustavo

> ---
>   drivers/dma/fsl-edma-common.h | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/dma/fsl-edma-common.h b/drivers/dma/fsl-edma-common.h
> index 40d50cc3d75a..bb5221158a77 100644
> --- a/drivers/dma/fsl-edma-common.h
> +++ b/drivers/dma/fsl-edma-common.h
> @@ -225,7 +225,7 @@ struct fsl_edma_engine {
>   	bool			big_endian;
>   	struct edma_regs	regs;
>   	u64			chan_masked;
> -	struct fsl_edma_chan	chans[];
> +	struct fsl_edma_chan	chans[] __counted_by(n_chans);
>   };
>   
>   #define edma_read_tcdreg(chan, __name)				\