Re: [PATCH] iio: light: acpi-als: Fix trigger reference leak in acpi_als_probe()

[Jonathan Cameron]

On Wed, 16 Sep 2026 16:34:40 +0000
Wentao Liang <vulab@xxxxxxxxxxx> wrote:

> The reference taken with iio_trigger_get() is only dropped by
> iio_dev_release() when INDIO_BUFFER_TRIGGERED is set. If
> devm_iio_triggered_buffer_setup() fails before setting that mode, the
> reference acquired for indio_dev->trig leaks. Move the
> iio_trigger_get() after the buffer setup succeeds.
> 
> Fixes: 24b84444eb6f ("iio: acpi_als: Add trigger support")
> Cc: stable@xxxxxxxxxxxxxxx
> Signed-off-by: Wentao Liang <vulab@xxxxxxxxxxx>
Same again.  Not going to introduce subtle ordering fixes like this.
We need a comprehensive solution with appropriate changes in the
IIO core to handle cleaning that reference up. See bma220 for
more on this.
> ---
>  drivers/iio/light/acpi-als.c | 11 ++++++-----
>  1 file changed, 6 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/iio/light/acpi-als.c b/drivers/iio/light/acpi-als.c
> index ab229318dce9..ad95057d99c2 100644
> --- a/drivers/iio/light/acpi-als.c
> +++ b/drivers/iio/light/acpi-als.c
> @@ -206,11 +206,6 @@ static int acpi_als_probe(struct platform_device *pdev)
>  	ret = devm_iio_trigger_register(dev, als->trig);
>  	if (ret)
>  		return ret;
> -	/*
> -	 * Set hardware trigger by default to let events flow when
> -	 * BIOS support notification.
> -	 */
> -	indio_dev->trig = iio_trigger_get(als->trig);
>  
>  	ret = devm_iio_triggered_buffer_setup(dev, indio_dev,
>  					      iio_pollfunc_store_time,
> @@ -219,6 +214,12 @@ static int acpi_als_probe(struct platform_device *pdev)
>  	if (ret)
>  		return ret;
>  
> +	/*
> +	 * Set hardware trigger by default to let events flow when
> +	 * BIOS support notification.
> +	 */
> +	indio_dev->trig = iio_trigger_get(als->trig);
> +
>  	ret = devm_iio_device_register(dev, indio_dev);
>  	if (ret)
>  		return ret;