linux-kernel - Re: [PATCH v2 0/6] media: uvcvideo: Implement the Privacy GPIO as a subdevice

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20241110134808.328da075@foz.lan>
Date: Sun, 10 Nov 2024 13:48:08 +0100
From: Mauro Carvalho Chehab <mchehab+huawei@...nel.org>
To: Ricardo Ribalda <ribalda@...omium.org>
Cc: Hans Verkuil <hverkuil@...all.nl>, Hans de Goede <hdegoede@...hat.com>,
 Laurent Pinchart <laurent.pinchart@...asonboard.com>, Mauro Carvalho Chehab
 <mchehab@...nel.org>, Sakari Ailus <sakari.ailus@...ux.intel.com>,
 linux-kernel@...r.kernel.org, linux-media@...r.kernel.org, Yunke Cao
 <yunkec@...omium.org>
Subject: Re: [PATCH v2 0/6] media: uvcvideo: Implement the Privacy GPIO as a
 subdevice

Em Sun, 10 Nov 2024 11:37:46 +0100
Ricardo Ribalda <ribalda@...omium.org> escreveu:

> > > Privacy matters only when streaming. IMO the Kernel check for it needs to
> > > be done at DQBUF time and at read() calls, as one can enable/disable the
> > > camera while doing videoconf calls. I do that a lot with app "soft" buttons,
> > > and on devices that physically support cutting the video.  
> >
> > We could add a vb2_s_privacy(bool privacy) function to vb2 to tell vb2 if the privacy
> > mode is on. And if so, take action. E.g. calling QBUF/DQBUF would return a -EACCES error.
> >
> > That will ensure consistent behavior for all drivers that have a privacy function.  
> 
> I am not against adding a feature like this, but we still need a way
> to notify userspace about a change of the privacy state when the user
> presses it.
> Controls are great for this.

It doesn't sound a good idea. See, from users PoV, they want the stream
to start with black frames when privacy is on, and dynamically being
able to enable/disable actual frame output. So, the best is to have the
stream running independently of the privacy being enabled or not.

Thanks,
Mauro