Hi,
On 11/1/21 11:44, Andy Shevchenko wrote:
> On Mon, Nov 1, 2021 at 12:31 PM Hans de Goede <hdegoede@xxxxxxxxxx> wrote:
>> On 10/25/21 13:31, Andy Shevchenko wrote:
>>> On Mon, Oct 25, 2021 at 12:42 PM Hans de Goede <hdegoede@xxxxxxxxxx> wrote:
>
> ...
>
>>>> +int skl_int3472_get_sensor_adev_and_name(struct device *dev,
>>>> + struct acpi_device **sensor_adev_ret,
>>>> + const char **name_ret)
>>>> +{
>>>> + struct acpi_device *adev = ACPI_COMPANION(dev);
>>>> + struct acpi_device *sensor;
>>>> + int ret = 0;
>>>> +
>>>> + sensor = acpi_dev_get_first_consumer_dev(adev);
>>>> + if (!sensor) {
>>>> + dev_err(dev, "INT3472 seems to have no dependents.\n");
>>>> + return -ENODEV;
>>>> + }
>>>> +
>>>> + *name_ret = devm_kasprintf(dev, GFP_KERNEL, I2C_DEV_NAME_FORMAT,
>>>> + acpi_dev_name(sensor));
>>>> + if (!*name_ret)
>>>> + ret = -ENOMEM;
>>>> +
>>>> + if (ret == 0 && sensor_adev_ret)
>>>> + *sensor_adev_ret = sensor;
>>>> + else
>>>> + acpi_dev_put(sensor);
>>>> +
>>>> + return ret;
>>>
>>> The error path is twisted a bit including far staying ret=0 assignment.
>>>
>>> Can it be
>>>
>>> int ret;
>>> ...
>>> *name_ret = devm_kasprintf(dev, GFP_KERNEL, I2C_DEV_NAME_FORMAT,
>>> acpi_dev_name(sensor));
>>> if (!*name_ret) {
>>> acpi_dev_put(sensor);
>>> return -ENOMEM;
>>> }
>>>
>>> if (sensor_adev_ret)
>>> *sensor_adev_ret = sensor;
>>>
>>> return 0;
>>>
>>> ?
>>
>> That misses an acpi_dev_put(sensor) when sensor_adev_ret == NULL.
>
> else
> acpi_dev_put(...);
Then we have 2 acpi_dev_put() paths, IMHO the original code
which clearly states that we keep the ref:
if (success && returning-the-ref)
and put the ref in all other cases is better then having
2 separate put paths.
Regards,
Hans
