On 8/18/09, Alan Jenkins <sourcejedi.lkml@xxxxxxxxxxxxxx> wrote:
> On 8/18/09, Marcel Holtmann <marcel@xxxxxxxxxxxx> wrote:
>> Hi Mario,
>
> ...
>
>>> +static int setup_rfkill(void)
>>> +{
>>> + int ret;
>>> +
>>> + wifi_rfkill = rfkill_alloc("compal-wifi", NULL,
>>> RFKILL_TYPE_WLAN,
>>> + &compal_rfkill_ops, (void *)
>>> WLAN_MASK);
>>> + if (!wifi_rfkill) {
>>> + ret = -ENOMEM;
>>> + goto err_wifi;
>>> + }
>>> + ret = rfkill_register(wifi_rfkill);
>>> + if (ret)
>>> + goto err_wifi;
>>> +
>>> + bluetooth_rfkill = rfkill_alloc("compal-bluetooth", NULL,
>>> RFKILL_TYPE_BLUETOOTH,
>>> + &compal_rfkill_ops, (void *)
>>> BT_MASK);
>>> + if (!bluetooth_rfkill) {
>>> + ret = -ENOMEM;
>>> + goto err_bt;
>>> + }
>>> + ret = rfkill_register(bluetooth_rfkill);
>>> + if (ret)
>>> + goto err_bt;
>>> +
>>> + return 0;
>>> +err_bt:
>>> + rfkill_destroy(bluetooth_rfkill);
>>> + if (bluetooth_rfkill)
>>> + rfkill_unregister(bluetooth_rfkill);
>>> +err_wifi:
>>> + rfkill_destroy(wifi_rfkill);
>>> + if (wifi_rfkill)
>>> + rfkill_unregister(wifi_rfkill);
>>
>> I don't understand how this is not a potential NULL pointer dereference.
>> There might some good luck that the pointer is still valid at that time,
>> but I highly doubt it. So please unregister before destory.
>
> Wrong as well :-).
>
> If you fail to register wifi_rfkill, you should *only* call
> rfkill_destroy(). So I think it should look like this:
>
> + if (wifi_rfkill)
> + rfkill_unregister(wifi_rfkill);
> +err_wifi:
> + rfkill_destroy(wifi_rfkill);
>
> ...
>
>>> @@ -420,6 +518,10 @@
>>> platform_device_unregister(compal_device);
>>> platform_driver_unregister(&compal_driver);
>>> backlight_device_unregister(compalbl_device);
>>> + if (wifi_rfkill)
>>> + rfkill_unregister(wifi_rfkill);
>>> + if (bluetooth_rfkill)
>>> + rfkill_unregister(bluetooth_rfkill);
>>
>> Same here. It should never ever succeeded in the first place. You can
>> call it conditionally.
>
> They're already called conditionally. I assume you mean unconditionally
> here.
Also, you're missing the calls to rfkill_destroy() here.
Whew, I think that's everything. I hope you find the feedback useful,
despite it being a little fragmented.
Regards
Alan
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