Re: [PATCH 05/21] dmaengine: hisilicon: Annotate struct hisi_dma_dev with __counted_by

From: "Gustavo A. R. Silva" <gustavo@embeddedor.com>
To: Kees Cook <keescook@chromium.org>, Vinod Koul <vkoul@kernel.org>
Cc: Zhou Wang <wangzhou1@hisilicon.com>, Jie Hai <haijie1@huawei.com>,
	dmaengine@vger.kernel.org, Hector Martin <marcan@marcan.st>,
	Sven Peter <sven@svenpeter.dev>,
	Alyssa Rosenzweig <alyssa@rosenzweig.io>,
	Ludovic Desroches <ludovic.desroches@microchip.com>,
	Tudor Ambarus <tudor.ambarus@linaro.org>,
	Lars-Peter Clausen <lars@metafoo.de>,
	Andy Gross <agross@kernel.org>,
	Bjorn Andersson <andersson@kernel.org>,
	Konrad Dybcio <konrad.dybcio@linaro.org>,
	Green Wan <green.wan@sifive.com>,
	Orson Zhai <orsonzhai@gmail.com>,
	Baolin Wang <baolin.wang@linux.alibaba.com>,
	Chunyan Zhang <zhang.lyra@gmail.com>,
	Patrice Chotard <patrice.chotard@foss.st.com>,
	Maxime Coquelin <mcoquelin.stm32@gmail.com>,
	Alexandre Torgue <alexandre.torgue@foss.st.com>,
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Subject: Re: [PATCH 05/21] dmaengine: hisilicon: Annotate struct hisi_dma_dev with __counted_by
Date: Thu, 17 Aug 2023 19:23:29 -0600	[thread overview]
Message-ID: <ff1cd85f-c481-e23a-1cbd-aabe51f4651b@embeddedor.com> (raw)
In-Reply-To: <20230817235859.49846-5-keescook@chromium.org>


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 hisi_dma_dev.
> 
> [1] https://github.com/kees/kernel-tools/blob/trunk/coccinelle/examples/counted_by.cocci
> 
> Cc: Vinod Koul <vkoul@kernel.org>
> Cc: Zhou Wang <wangzhou1@hisilicon.com>
> Cc: Jie Hai <haijie1@huawei.com>
> Cc: dmaengine@vger.kernel.org
> Signed-off-by: Kees Cook <keescook@chromium.org>

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

Thanks
--
Gustavo

> ---
>   drivers/dma/hisi_dma.c | 2 +-
>   1 file changed, 1 insertion(+), 1 deletion(-)
> 
> diff --git a/drivers/dma/hisi_dma.c b/drivers/dma/hisi_dma.c
> index c1350a36fddd..4c47bff81064 100644
> --- a/drivers/dma/hisi_dma.c
> +++ b/drivers/dma/hisi_dma.c
> @@ -163,7 +163,7 @@ struct hisi_dma_dev {
>   	u32 chan_depth;
>   	enum hisi_dma_reg_layout reg_layout;
>   	void __iomem *queue_base; /* queue region start of register */
> -	struct hisi_dma_chan chan[];
> +	struct hisi_dma_chan chan[] __counted_by(chan_num);
>   };
>   
>   #ifdef CONFIG_DEBUG_FS