Re: [PATCH v3] leds: Introduce userspace leds driver

[David Lechner <david@lechnology.com>]

On 09/15/2016 09:54 AM, Jacek Anaszewski wrote:
> Hi Pavel,
>
> On 09/15/2016 03:08 PM, Pavel Machek wrote:
>> Hi!
>>
>>>> +    if (copy_from_user(&udev->user_dev, buffer,
>>>> +               sizeof(struct uleds_user_dev))) {
>>>> +        ret = -EFAULT;
>>>> +        goto out;
>>>> +    }
>>>> +
>>>> +    if (!udev->user_dev.name[0]) {
>>>> +        ret = -EINVAL;
>>>> +        goto out;
>>>> +    }
>>>> +
>>>> +    ret = led_classdev_register(NULL, &udev->led_cdev);
>>>> +    if (ret < 0)
>>>> +        goto out;
>>
>> No sanity checking on the name -> probably a security hole. Do not
>> push this upstream before this is fixed.
>
> Thanks for catching this.
>
> David, please check if the LED name sticks to the LED class
> device naming convention.

I don't think it is a good idea to enforce the LED class naming 
convention. Someone may have a userspace application they want to test 
that has a hard-coded name that does not follow the convention.


>
> And one thing that caught my eye only now - please use
> devm_led_classdev_register().

How do I use devm_* when there is no parent device?


>
> For now I'm dropping the patch.
>