Re: [PATCH] iio: adc: palmas_gpadc: fix NULL dereference on rmmod

From: Jonathan Cameron
Date: Sat Mar 18 2023 - 12:15:46 EST


On Mon, 13 Mar 2023 21:50:29 +0100
Patrik Dahlström <risca@xxxxxxxxxxxxxx> wrote:

> Calling dev_to_iio_dev() on a platform device pointer is undefined and
> will make adc NULL.
>
> Signed-off-by: Patrik Dahlström <risca@xxxxxxxxxxxxxx>

Hi Patrik,

Looks good so applied to the fixes-togreg branch of iio.git.

Whilst we are here, this would be a trivial driver to take fully device
managed. The only slightly messy bit is that it would need
a devm_add_action_or_reset() + custom callback to handle the
device_wakeup_enable().

On the off chance you can test it I'll send a patch in a few mins.
Note that will depend on this one going up stream first and that
I haven't done more than build test it.

Thanks,

Jonathan


> ---
> drivers/iio/adc/palmas_gpadc.c | 2 +-
> 1 file changed, 1 insertion(+), 1 deletion(-)
>
> diff --git a/drivers/iio/adc/palmas_gpadc.c b/drivers/iio/adc/palmas_gpadc.c
> index 61e80bf3d05e..6db6f3bc768a 100644
> --- a/drivers/iio/adc/palmas_gpadc.c
> +++ b/drivers/iio/adc/palmas_gpadc.c
> @@ -638,7 +638,7 @@ static int palmas_gpadc_probe(struct platform_device *pdev)
>
> static int palmas_gpadc_remove(struct platform_device *pdev)
> {
> - struct iio_dev *indio_dev = dev_to_iio_dev(&pdev->dev);
> + struct iio_dev *indio_dev = dev_get_drvdata(&pdev->dev);
> struct palmas_gpadc *adc = iio_priv(indio_dev);
>
> if (adc->wakeup1_enable || adc->wakeup2_enable)