Re: [PATCH] pinctrl: intel: fix NULL pointer deref

From: Mika Westerberg <mika.westerberg@linux.intel.com>
To: Henning Schild <henning.schild@siemens.com>
Cc: linux-kernel@vger.kernel.org, linux-gpio@vger.kernel.org,
	Andy Shevchenko <andy@kernel.org>,
	Linus Walleij <linus.walleij@linaro.org>
Subject: Re: [PATCH] pinctrl: intel: fix NULL pointer deref
Date: Wed, 9 Jun 2021 13:12:10 +0300	[thread overview]
Message-ID: <YMCT+izizEg0gPLD@lahna.fi.intel.com> (raw)
In-Reply-To: <20210609062722.9132-1-henning.schild@siemens.com>

Hi,

On Wed, Jun 09, 2021 at 08:27:22AM +0200, Henning Schild wrote:
> match could be NULL in which case we do not go ACPI after all
> 
> Signed-off-by: Henning Schild <henning.schild@siemens.com>
> ---
>  drivers/pinctrl/intel/pinctrl-intel.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/pinctrl/intel/pinctrl-intel.c b/drivers/pinctrl/intel/pinctrl-intel.c
> index 85750974d182..dca17bb76cac 100644
> --- a/drivers/pinctrl/intel/pinctrl-intel.c
> +++ b/drivers/pinctrl/intel/pinctrl-intel.c
> @@ -1601,12 +1601,12 @@ const struct intel_pinctrl_soc_data *intel_pinctrl_get_soc_data(struct platform_
>  	const struct intel_pinctrl_soc_data *data = NULL;
>  	const struct intel_pinctrl_soc_data **table;
>  	struct acpi_device *adev;
> +	const void *match;
>  	unsigned int i;
>  
>  	adev = ACPI_COMPANION(&pdev->dev);
> -	if (adev) {
> -		const void *match = device_get_match_data(&pdev->dev);
> -
> +	match = device_get_match_data(&pdev->dev);

Actually we don't even call intel_pinctrl_get_soc_data() if the ACPI ID
is not listed in the corresponding driver's module table. So I don't
think match can ever be NULL.

But feel free to prove me wrong ;-)