Subject: Re: How kauth can make meaningful decisions about passthru ioctls
To: Elad Efrat <>
From: Steven M. Bellovin <>
List: tech-kern
Date: 11/30/2006 08:52:32
On Thu, 30 Nov 2006 15:10:25 +0200
Elad Efrat <> wrote:

> Thor Lancelot Simon wrote:
> > Sure.  We're concerned about what the ioctl being passed-through
> > could cause the device to do.  Think about what amr(4) would have
> > to do if it didn't know how to parse the sub-commands: it'd have to
> > tell the listener "it could be any of these: ..." .
> > 
> > We could, I suppose, order the commands from "safest" to "most
> > dangerous" and require that the question indicate the "most
> > dangerous".  But what's "more dangerous", writing the device data
> > or writing the device configuration?  I think a similar issue
> > exists even for read.
> sounds logical. unless someone objects, I'll come up with a diff.
What sounds logical?  An ordering?  I don't think it makes much sense
at all.  What's wrong with a bitmask? 

		--Steve Bellovin,