Re: [RFC v1] USB: core: add USBDEVFS_REVOKE ioctl

[Bastien Nocera <hadess@hadess.net>]

On Mon, 2022-04-25 at 17:45 +0200, Greg Kroah-Hartman wrote:
> But back to the original question, what programs would use this that
> today offer direct access to USB devices through libusb?  I can maybe
> think of some fingerprint scanners and some flatbed scanners
> (printers?)
> But those are generally rare and the fingerprint scanners only have
> limited access to the device already.

fingerprint readers are handled through a privileged daemon for the
past 14 years:
https://fprint.freedesktop.org/

Looking through libusb_open() users on the Debian repo[1], I could find
those types of devices that could make use of sandboxing:
- all manners of single-board computers and programmable chips and
devices (avrdude, STLink, sunxi bootloader, flashrom, etc.)
- 3D printers
- scanners
- LCD "displays"
- user-space webcam and still cameras
- game controllers
- video/audio capture devices
- sensors
- software-defined radios
- DJ/music equipment
- protocol analysers

There's also Rio500 support which I'm particularly attached to, and
many many more device types, including one that should eventually get a
kernel driver, because prototyping in user-space in Python or
Javascript is probably easier than in C.

[1]:
https://codesearch.debian.net/search?q=libusb_open&literal=1&perpkg=1