Subject: Re: [PATCH] drm/tegra: sor: add NULL check on of_match_device()
 return value
To: "Gustavo A. R. Silva" <garsilva@embeddedor.com>,
        Thierry Reding <thierry.reding@gmail.com>,
        David Airlie <airlied@linux.ie>
CC: <dri-devel@lists.freedesktop.org>, <linux-tegra@vger.kernel.org>,
        <linux-kernel@vger.kernel.org>
References: <20170707061119.GA12563@embeddedgus>
From: Jon Hunter <jonathanh@nvidia.com>
Message-ID: <27ec9e14-f5da-4240-1158-e3c9af4d6f10@nvidia.com>
Date: Fri, 7 Jul 2017 08:42:09 +0100
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On 07/07/17 07:11, Gustavo A. R. Silva wrote:
> Check return value from call to of_match_device()
> in order to prevent a NULL pointer dereference.
> 
> In case of NULL print error message and return.
> 
> Signed-off-by: Gustavo A. R. Silva <garsilva@embeddedor.com>
> ---
>  drivers/gpu/drm/tegra/sor.c | 4 ++++
>  1 file changed, 4 insertions(+)
> 
> diff --git a/drivers/gpu/drm/tegra/sor.c b/drivers/gpu/drm/tegra/sor.c
> index a8f5289..ca3d9b1 100644
> --- a/drivers/gpu/drm/tegra/sor.c
> +++ b/drivers/gpu/drm/tegra/sor.c
> @@ -2538,6 +2538,10 @@ static int tegra_sor_probe(struct platform_device *pdev)
>  	int err;
>  
>  	match = of_match_device(tegra_sor_of_match, &pdev->dev);
> +	if (!match) {
> +		dev_err(&pdev->dev, "failed to match device\n");
> +		return -ENODEV;
> +	}

Given that Tegra always uses device-tree, I believe that this cannot
happen and so this additional check is not needed.

Jon

-- 
nvpublic