If a second dummy client that talks to the actual I2C address was
created in probe(), there should be a proper cleanup on driver and
device removal to avoid leakage.

So unregister the dummy client via another callback.

Reviewed-by: Hans de Goede <hdegoede@redhat.com>
Suggested-by: Hans de Goede <hdegoede@redhat.com>
Fixes: c1e62062ff54 ("iio: light: cm32181: Handle CM3218 ACPI devices with 2 I2C resources")
Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=2152281
Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>
---
v4:
 - Remove logging kmalloc failures.

v3:
 - Use devm_add_action_or_reset() in a correct place.
 - Wording.

v2:
 - Use devm_add_action_or_reset() instead of remove() callback to avoid
   race.

 drivers/iio/light/cm32181.c | 12 ++++++++++++
 1 file changed, 12 insertions(+)

diff --git a/drivers/iio/light/cm32181.c b/drivers/iio/light/cm32181.c
index b1674a5bfa368..d4a34a3bf00d9 100644
--- a/drivers/iio/light/cm32181.c
+++ b/drivers/iio/light/cm32181.c
@@ -429,6 +429,14 @@ static const struct iio_info cm32181_info = {
 	.attrs			= &cm32181_attribute_group,
 };
 
+static void cm32181_unregister_dummy_client(void *data)
+{
+	struct i2c_client *client = data;
+
+	/* Unregister the dummy client */
+	i2c_unregister_device(client);
+}
+
 static int cm32181_probe(struct i2c_client *client)
 {
 	struct device *dev = &client->dev;
@@ -460,6 +468,10 @@ static int cm32181_probe(struct i2c_client *client)
 		client = i2c_acpi_new_device(dev, 1, &board_info);
 		if (IS_ERR(client))
 			return PTR_ERR(client);
+
+		ret = devm_add_action_or_reset(dev, cm32181_unregister_dummy_client, client);
+		if (ret)
+			return ret;
 	}
 
 	cm32181 = iio_priv(indio_dev);
-- 
2.34.1

Hi,

On 2/23/23 03:00, Kai-Heng Feng wrote:
> If a second dummy client that talks to the actual I2C address was
> created in probe(), there should be a proper cleanup on driver and
> device removal to avoid leakage.
> 
> So unregister the dummy client via another callback.
> 
> Reviewed-by: Hans de Goede <hdegoede@redhat.com>
> Suggested-by: Hans de Goede <hdegoede@redhat.com>
> Fixes: c1e62062ff54 ("iio: light: cm32181: Handle CM3218 ACPI devices with 2 I2C resources")
> Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=2152281
> Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>

Thanks this patch looks good to me now, and you
already added my Reviewed-by, so from my POV this
is ready for merging now.

Regards,

Hans

> ---
> v4:
>  - Remove logging kmalloc failures.
> 
> v3:
>  - Use devm_add_action_or_reset() in a correct place.
>  - Wording.
> 
> v2:
>  - Use devm_add_action_or_reset() instead of remove() callback to avoid
>    race.
> 
>  drivers/iio/light/cm32181.c | 12 ++++++++++++
>  1 file changed, 12 insertions(+)
> 
> diff --git a/drivers/iio/light/cm32181.c b/drivers/iio/light/cm32181.c
> index b1674a5bfa368..d4a34a3bf00d9 100644
> --- a/drivers/iio/light/cm32181.c
> +++ b/drivers/iio/light/cm32181.c
> @@ -429,6 +429,14 @@ static const struct iio_info cm32181_info = {
>  	.attrs			= &cm32181_attribute_group,
>  };
>  
> +static void cm32181_unregister_dummy_client(void *data)
> +{
> +	struct i2c_client *client = data;
> +
> +	/* Unregister the dummy client */
> +	i2c_unregister_device(client);
> +}
> +
>  static int cm32181_probe(struct i2c_client *client)
>  {
>  	struct device *dev = &client->dev;
> @@ -460,6 +468,10 @@ static int cm32181_probe(struct i2c_client *client)
>  		client = i2c_acpi_new_device(dev, 1, &board_info);
>  		if (IS_ERR(client))
>  			return PTR_ERR(client);
> +
> +		ret = devm_add_action_or_reset(dev, cm32181_unregister_dummy_client, client);
> +		if (ret)
> +			return ret;
>  	}
>  
>  	cm32181 = iio_priv(indio_dev);

On Thu, 23 Feb 2023 09:41:29 +0100
Hans de Goede <hdegoede@redhat.com> wrote:

> Hi,
> 
> On 2/23/23 03:00, Kai-Heng Feng wrote:
> > If a second dummy client that talks to the actual I2C address was
> > created in probe(), there should be a proper cleanup on driver and
> > device removal to avoid leakage.
> > 
> > So unregister the dummy client via another callback.
> > 
> > Reviewed-by: Hans de Goede <hdegoede@redhat.com>
> > Suggested-by: Hans de Goede <hdegoede@redhat.com>
> > Fixes: c1e62062ff54 ("iio: light: cm32181: Handle CM3218 ACPI devices with 2 I2C resources")
> > Bugzilla: https://bugzilla.redhat.com/show_bug.cgi?id=2152281
> > Signed-off-by: Kai-Heng Feng <kai.heng.feng@canonical.com>  
> 
> Thanks this patch looks good to me now, and you
> already added my Reviewed-by, so from my POV this
> is ready for merging now.
> 
Applied to the fixes-togreg branch of iio.git and marked for stable inclusion.

Thanks,

Jonathan

> Regards,
> 
> Hans
> 
> > ---
> > v4:
> >  - Remove logging kmalloc failures.
> > 
> > v3:
> >  - Use devm_add_action_or_reset() in a correct place.
> >  - Wording.
> > 
> > v2:
> >  - Use devm_add_action_or_reset() instead of remove() callback to avoid
> >    race.
> > 
> >  drivers/iio/light/cm32181.c | 12 ++++++++++++
> >  1 file changed, 12 insertions(+)
> > 
> > diff --git a/drivers/iio/light/cm32181.c b/drivers/iio/light/cm32181.c
> > index b1674a5bfa368..d4a34a3bf00d9 100644
> > --- a/drivers/iio/light/cm32181.c
> > +++ b/drivers/iio/light/cm32181.c
> > @@ -429,6 +429,14 @@ static const struct iio_info cm32181_info = {
> >  	.attrs			= &cm32181_attribute_group,
> >  };
> >  
> > +static void cm32181_unregister_dummy_client(void *data)
> > +{
> > +	struct i2c_client *client = data;
> > +
> > +	/* Unregister the dummy client */
> > +	i2c_unregister_device(client);
> > +}
> > +
> >  static int cm32181_probe(struct i2c_client *client)
> >  {
> >  	struct device *dev = &client->dev;
> > @@ -460,6 +468,10 @@ static int cm32181_probe(struct i2c_client *client)
> >  		client = i2c_acpi_new_device(dev, 1, &board_info);
> >  		if (IS_ERR(client))
> >  			return PTR_ERR(client);
> > +
> > +		ret = devm_add_action_or_reset(dev, cm32181_unregister_dummy_client, client);
> > +		if (ret)
> > +			return ret;
> >  	}
> >  
> >  	cm32181 = iio_priv(indio_dev);  
>