[Date Prev][Date Next] [Thread Prev][Thread Next] [Date Index] [Thread Index]

Re: Locking of serial devices and devfs

On Fri, Jun 22, 2001 at 01:42:22PM +0200, Wichert Akkerman wrote:
> Previously Marcus Brinkmann wrote:
> > I am not sure I answered your question, but one thing jas to be kept in
> > mind:  That there is no central authority for such resources, and as such
> > there is no central authority how such resources should be accessed or
> > shared.
> In other words there is no way to guarantee that if user A is using
> a serial port user B can't access it as well and snoop/insert traffic?

If he has root privileges, or the administrator is stupid enough to set up
two devices pointing to the underlying kernel device with public permissions
broad enough, then yes.

(Mach kernel devices are protected by requiring superuser privileges,
"device files" in /dev are protected by the associated file permissions.
That is not what is different from Linux).

What I mean is more the scenario that affects e2fsprogs:  It can't check
if some other file system is identical to the root filesystem, because the
notiion of filesystem as used in the Hurd isn't even expressable by a dev
maj/min nr pair.


`Rhubarb is no Egyptian god.' Debian http://www.debian.org brinkmd@debian.org
Marcus Brinkmann              GNU    http://www.gnu.org    marcus@gnu.org

Reply to: