RE: Linux Security *Module* Framework (Was: LSM conversion to static interface)

["Hua Zhong" <hzhong@gmail.com>]

I think you may be misinterpreting the word "poor" here.

Many people in this thread consider a security solution "poor" because it's
not "complete" or "perfect": it may work against attack ABC but not attack
XYZ. The defendants say that XYZ isn't possible in the environment that it's
supposed to be used, or XYZ may be too expensive to be worth implementing,
or they just are rare enough to be ignored. Heck, all security solutions
could be broke given physical access.

Implementing a security solution has a cost. Bypassing it also has a cost.
Sometimes it's economy, not technique, decides whether a particular security
solution is a good one.

Locks are a good example for this. It has a low cost/effect ratio, and very
easy to use. Is it 100% safe? Definitely not. People lock their bikes to a
tree when they enter a supermarket because it's reasonably safe. But leaving
their bikes like that over a few nights on a downtown street? Probably not a
good idea. Don't assume all people are idiots who do not know that (ok, some
people are, so the lock's manual states "it can be bypassed by a skilled
thief").

But what tapes are good for? I don't know what kind of value it adds to the
discussion.

> -----Original Message-----
> From: linux-kernel-owner@vger.kernel.org [mailto:linux-kernel-
> owner@vger.kernel.org] On Behalf Of Pavel Machek
> Sent: Saturday, October 27, 2007 11:29 AM
> To: Ray Lee
> Cc: Alan Cox; Chris Wright; Casey Schaufler; Adrian Bunk; Simon Arlott;
> linux-kernel@vger.kernel.org; linux-security-module@vger.kernel.org;
> Jan Engelhardt; Linus Torvalds; Andreas Gruenbacher; Thomas Fricaccia;
> Jeremy Fitzhardinge; James Morris; Crispin Cowan; Giacomo Catenazzi
> Subject: Re: Linux Security *Module* Framework (Was: LSM conversion to
> static interface)
> 
> Hi!
> 
> > > > The idea that poor security is worse than no security is
> fallacious,
> > > > and not backed up by common experience.
> > >
> > > There is a ton of evidence both in computing and outside of it
> which
> > > shows that poor security can be very much worse than no security at
> all.
> >
> > (So, I take it that you *don't* lock your bike up, as poor security
> is
> > worse than none?)
> 
> I do lock my bike with combination lock I found somewhere and cracked
> in five minutes... sometimes.
> 
> But do you suggest that I use paper tape to 'lock' my bike to
> streetlight? You just said that poor security is better than none,
> right?
> 
> 							Pavel
> --
> (english) http://www.livejournal.com/~pavelmachek
> (cesky, pictures)
> http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/blog.html
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