Re: [PATCH -next 1/2] dmaengine: fsl-edma: use struct_size() helper

[Vinod Koul <vkoul@kernel.org>]

On 16-08-23, 10:03, Yu Liao wrote:
> Make use of the struct_size() helper instead of an open-coded version,
> in order to avoid any potential type mistakes or integer overflows that,
> in the worst scenario, could lead to heap overflows.
> 
> Signed-off-by: Yu Liao <liaoyu15@huawei.com>
> ---
>  drivers/dma/fsl-edma.c | 3 +--
>  1 file changed, 1 insertion(+), 2 deletions(-)
> 
> diff --git a/drivers/dma/fsl-edma.c b/drivers/dma/fsl-edma.c
> index e40769666e39..caca3566ba82 100644
> --- a/drivers/dma/fsl-edma.c
> +++ b/drivers/dma/fsl-edma.c
> @@ -270,7 +270,6 @@ static int fsl_edma_probe(struct platform_device *pdev)
>  	struct device_node *np = pdev->dev.of_node;
>  	struct fsl_edma_engine *fsl_edma;
>  	const struct fsl_edma_drvdata *drvdata = NULL;
> -	struct fsl_edma_chan *fsl_chan;
>  	struct edma_regs *regs;
>  	int len, chans;
>  	int ret, i;
> @@ -288,7 +287,7 @@ static int fsl_edma_probe(struct platform_device *pdev)
>  		return ret;
>  	}
>  
> -	len = sizeof(*fsl_edma) + sizeof(*fsl_chan) * chans;
> +	len = struct_size(fsl_edma, chans, chans);
>  	fsl_edma = devm_kzalloc(&pdev->dev, len, GFP_KERNEL);

Drop len and use struct_size() here...

>  	if (!fsl_edma)
>  		return -ENOMEM;
> -- 
> 2.25.1

-- 
~Vinod