Re: [PATCH v2 1/3] iio: adc: ad7192: Fix null pointer dereference on probe

[Jonathan Cameron <jic23@kernel.org>]

On Thu, 13 Apr 2023 10:28:11 +0200
Fabrizio Lamarque <fl.scratchpad@gmail.com> wrote:

> Pointer to indio_dev structure is obtained via spi_get_drvdata() at
> the beginning of function ad7192_setup(), but the spi->dev->driver_data
> member is not initialized, hence a NULL pointer is returned.
> 
> Fixed by changing ad7192_setup() signature to take pointer to struct
> iio_dev, and get ad7192_state pointer via st = iio_priv(indio_dev);
> 
> Fixes: bd5dcdeb3fd0 iio: adc: ad7192: convert to device-managed functions
> Signed-off-by: Fabrizio Lamarque <fl.scratchpad@gmail.com>
> ---
> Changes in v2: obtained ad7192_state from iio_dev pointer as suggested
> by Jonathan, removed Reviewed-by since the entire patch changed its
> content.

Great. Please just tidy up the Fixes tag formatting and send a v3.

Note that we are very late in current cycle, so I'll only queue these
up now for after 6.4-rc1 is available.  They'll get pulled back into stable
trees after that (in about 3-4 weeks time).

Thanks,

Jonathan

> 
>  drivers/iio/adc/ad7192.c | 6 +++---
>  1 file changed, 3 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/iio/adc/ad7192.c b/drivers/iio/adc/ad7192.c
> index 55a6ab591016..94a9cf34a255 100644
> --- a/drivers/iio/adc/ad7192.c
> +++ b/drivers/iio/adc/ad7192.c
> @@ -380,9 +380,9 @@ static int ad7192_of_clock_select(struct ad7192_state *st)
>   return clock_sel;
>  }
> 
> -static int ad7192_setup(struct ad7192_state *st, struct device_node *np)
> +static int ad7192_setup(struct iio_dev *indio_dev, struct device_node *np)
>  {
> - struct iio_dev *indio_dev = spi_get_drvdata(st->sd.spi);
> + struct ad7192_state *st = iio_priv(indio_dev);
>   bool rej60_en, refin2_en;
>   bool buf_en, bipolar, burnout_curr_en;
>   unsigned long long scale_uv;
> @@ -1073,7 +1073,7 @@ static int ad7192_probe(struct spi_device *spi)
>   }
>   }
> 
> - ret = ad7192_setup(st, spi->dev.of_node);
> + ret = ad7192_setup(indio_dev, spi->dev.of_node);
>   if (ret)
>   return ret;
> 
> --
> 2.34.1