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

[David Lechner]

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.