Re: [PATCH] [Patch v2] usbtv: Fix refcounting mixup

[Oliver Neukum <oneukum@suse.com>]

Am Dienstag, den 15.05.2018, 16:28 +0200 schrieb Hans Verkuil:
> On 05/15/18 15:07, Oliver Neukum wrote:
> > The premature free in the error path is blocked by V4L
> > refcounting, not USB refcounting. Thanks to
> > Ben Hutchings for review.
> > 
> > [v2] corrected attributions
> > 
> > Signed-off-by: Oliver Neukum <oneukum@suse.com>
> > Fixes: 50e704453553 ("media: usbtv: prevent double free in error case")
> > CC: stable@vger.kernel.org
> > Reported-by: Ben Hutchings <ben.hutchings@codethink.co.uk>
> > ---
> >  drivers/media/usb/usbtv/usbtv-core.c | 3 ++-
> >  1 file changed, 2 insertions(+), 1 deletion(-)
> > 
> > diff --git a/drivers/media/usb/usbtv/usbtv-core.c b/drivers/media/usb/usbtv/usbtv-core.c
> > index 5095c380b2c1..4a03c4d66314 100644
> > --- a/drivers/media/usb/usbtv/usbtv-core.c
> > +++ b/drivers/media/usb/usbtv/usbtv-core.c
> > @@ -113,7 +113,8 @@ static int usbtv_probe(struct usb_interface *intf,
> >  
> >  usbtv_audio_fail:
> >  	/* we must not free at this point */
> > -	usb_get_dev(usbtv->udev);
> > +	v4l2_device_get(&usbtv->v4l2_dev);
> 
> This is very confusing. I think it is much better to move the

Yes. It confused me.

> v4l2_device_register() call from usbtv_video_init to this probe function.

Yes, but it is called here. So you want to do it after registering the
audio?

	Regards
		Oliver