Re: Hyper-Threading Vulnerability

Vadim Lobanov
2005-05-13T18:30:51Z

On Fri, 13 May 2005, Andy Isaacson wrote:

> On Fri, May 13, 2005 at 10:32:48AM -0400, Jeff Garzik wrote:
> > Daniel Jacobowitz wrote:
> > > http://www.daemonology.net/hyperthreading-considered-harmful/
> >
> > Already read it. This link provides no more information than either of
> > the above links provide.
>
> He's posted his paper now.
>
> http://www.daemonology.net/papers/htt.pdf
>
> It's a side channel timing attack on data-dependent computation through
> the L1 and L2 caches. Nice work. In-the-wild exploitation is
> difficult, though; your timing gets screwed up if you get scheduled away
> from your victim, and you don't even know, because you can't tell where
> you were scheduled, so on any reasonably busy multiuser system it's not
> clear that the attack is practical.
>
> -andy
> -

Wouldn't scheduling appear as a rather big time delta (in measuring the
cache access times), so you would know to disregard that data point?

(Just wondering... :-) )

-Vadim