Re: [PATCH] Mmc: host - Fix possible NULL derefrence.

From: Marek Vasut <marex@denx.de>
To: Shailendra Verma <shailendra.v@samsung.com>,
	Ulf Hansson <ulf.hansson@linaro.org>,
	Fabio Estevam <fabio.estevam@nxp.com>,
	linux-mmc@vger.kernel.org, linux-kernel@vger.kernel.org,
	p.shailesh@samsung.com, ashish.kalra@samsung.com,
	Shailendra Verma <shailendra.capricorn@gmail.com>
Subject: Re: [PATCH] Mmc: host - Fix possible NULL derefrence.
Date: Mon, 30 Jan 2017 13:12:58 +0100	[thread overview]
Message-ID: <7439833a-e8cd-54b5-a020-4a16ac2d75a8@denx.de> (raw)
In-Reply-To: <1485751698-29036-1-git-send-email-shailendra.v@samsung.com>

On 01/30/2017 05:48 AM, Shailendra Verma wrote:
> of_match_device could return NULL, and so can cause a NULL
> pointer dereference later.
> 
> Signed-off-by: Shailendra Verma <shailendra.v@samsung.com>
> ---
>  drivers/mmc/host/mxs-mmc.c |    5 +++++
>  1 file changed, 5 insertions(+)
> 
> diff --git a/drivers/mmc/host/mxs-mmc.c b/drivers/mmc/host/mxs-mmc.c
> index 44ecebd..d12a5b7 100644
> --- a/drivers/mmc/host/mxs-mmc.c
> +++ b/drivers/mmc/host/mxs-mmc.c
> @@ -581,6 +581,11 @@ static int mxs_mmc_probe(struct platform_device *pdev)
>  	struct regulator *reg_vmmc;
>  	struct mxs_ssp *ssp;
>  
> +	if (!of_id) {
> +		dev_err(&pdev->dev, "Error: No device match found\n");
> +		return -ENODEV;
> +	}

The probe won't be called if OF match doesn't happen in the first place,
so this check is redundant, no ?

>  	irq_err = platform_get_irq(pdev, 0);
>  	if (irq_err < 0)
>  		return irq_err;
> 

-- 
Best regards,
Marek Vasut