usb4bsd patch review

[Hans Petter Selasky]

On Friday 22 August 2008, Alexander Leidinger wrote:
> Quoting "Kris Kennaway" <kris at FreeBSD.org> (from Fri, 22 Aug 2008
>
> 10:59:38 +0200):
> > Alexander Leidinger wrote:
> >> Quoting "M. Warner Losh" <imp at bsdimp.com> (from Thu, 21 Aug 2008
> >>
> >> 11:52:10 -0600 (MDT)):
> >>> In message: <48ADA66A.3040906 at FreeBSD.org>
> >>>
> >>>            Kris Kennaway <kris at freebsd.org> writes:
> >>> : Hans Petter Selasky wrote:
> >>> : > The USB stack will work fine without "usbconfig". Its purpose
> >>>
> >>> is : > mostly to
> >>>
> >>> : > view the currently attached USB devices, where the USB devices
> >>> : > are located
> >>> : > and to select a non-default USB configuration. One thing which
> >>> : > might be missed is to change owner and permission of a USB device,
> >>>
> >>> which means you
> >>>
> >>> : > must be either UID=root or GID=OPERATOR to be able to use USB
> >>> : > devices that
> >>> : > create devices under /dev/ .
> >>> :
> >>> : OK great, this isn't critical either.  I think all of the issues I
> >>> : raised are agreed upon now!
> >>
> >> Wait a moment. Does this mean the devfs stuff to handle the access
> >> rights (devfs.rules or manual chown/chmod by root) does not work
> >> with the new usb stuff? If the answer is yes, I would see this as
> >> some kind of nasty bug (I don't think this shall be a showstopper,
> >> as long as this is fixed later).
> >
> > Yes, he said it will be fixed later.
>
> You are aware that I point out that this may or may not suggest that
> HPS is circumventing the normal devfs infrastructure and that this may
> or may not be a problem and should be reviewed by someone with
> knowledge about the devfs infrastructure?
>
> And as he mentioned that in the context of the userland utilities, it
> may be interesting if this means if an USB specific userland utility
> will be responsible to change the ownership and file access or not. If
> yes, what are the consequences from a security point of view and what
> about POLA (devfs.rules, chown/chmod)?
>
> I want to see this new USB subsystem, but if the answer to the above
> paragraph is yes, then this would be a showstopper for me (IMO the
> replacement should work in this regard as before, I don't say it can
> not be changed after enough people agree that the replacement was
> successful).
>
> Bye,
> Alexander.

Hi Alexander,

You have to ask Paul Henning Kamp about that. He does not like the idea 
about /dev/ being the inventory list.

Besides, there are no more visible /dev/ devices. All devices are so-called 
cloneable and invisible, so you need a separate utility. The good news is 
that you can set the permissions on a USB subtree (a HUB and all subdevices) 
before devices are eventually plugged !

--HPS