Re: [PATCH 6/9] iio: adc: ti-adc128s052: validate SPI match data

[Jonathan Cameron]

On Fri, 25 Sep 2026 20:57:44 +0800
Jiale Yao <yaojiale02@xxxxxxx> wrote:

> SPI driver_override allows a device to bind to this driver without
> matching either the firmware tables or SPI device ID table. In that
> case, spi_get_device_match_data() returns NULL.
> 
> adc128_probe() also obtains the IIO device name by dereferencing the
> result of spi_get_device_id(), which is NULL on the same override path.
> The probe can therefore crash before it reaches the match data access.
> 
> Commit 572a00852635 ("iio: dac: ad5686: missing NULL check on match
> data") fixed the same driver_override issue in another SPI driver.
> Reject devices without match data and use the always available SPI
> modalias for the IIO device name.

Why this change?  The name is clearly encoded in a place that makes
it readily available and verifiably the right thing in a way that
spi->modalias does not.
There isn't any reason the IIO name would always match that even it
happens to do so here.


> 
> Fixes: d5f0da0c6972 ("iio: adc: ti-adc128s052: Switch to use spi_get_device_match_data()")
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Jiale Yao <yaojiale02@xxxxxxx>
> ---
>  drivers/iio/adc/ti-adc128s052.c | 8 +++++---
>  1 file changed, 5 insertions(+), 3 deletions(-)
> 
> diff --git a/drivers/iio/adc/ti-adc128s052.c b/drivers/iio/adc/ti-adc128s052.c
> index 1899813c1aee..f9a995ff403e 100644
> --- a/drivers/iio/adc/ti-adc128s052.c
> +++ b/drivers/iio/adc/ti-adc128s052.c
> @@ -195,12 +195,14 @@ static int adc128_probe(struct spi_device *spi)
>  	adc = iio_priv(indio_dev);
>  	adc->spi = spi;
>  
> -	indio_dev->name = spi_get_device_id(spi)->name;
> +	config = spi_get_device_match_data(spi);
> +	if (!config)
> +		return -ENODATA;
> +
> +	indio_dev->name = spi->modalias;
>  	indio_dev->modes = INDIO_DIRECT_MODE;
>  	indio_dev->info = &adc128_info;
>  
> -	config = spi_get_device_match_data(spi);
> -
>  	indio_dev->channels = config->channels;
>  	indio_dev->num_channels = config->num_channels;
>