Re: [PATCH 20/21] dmaengine: uniphier-xdmac: Annotate struct uniphier_xdmac_device with __counted_by

Gustavo A. R. Silva
2023-08-18T03:23:34Z

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@kernel.org>
> Cc: Kunihiko Hayashi <hayashi.kunihiko@socionext.com>
> Cc: Masami Hiramatsu <mhiramat@kernel.org>
> Cc: dmaengine@vger.kernel.org
> Cc: linux-arm-kernel@lists.infradead.org
> Signed-off-by: Kees Cook <keescook@chromium.org>

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

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 *