Re: [PATCH] Undo some of the pseudo-security madness

[Samium Gromoff <_deepfire@feelingofgreen.ru>]

At Mon, 22 Jan 2007 01:35:46 +0100,
Arjan van de Ven wrote:
> 
> 
> > the core of the problem are the cores which are customarily
> > dumped by lisps during the environment generation (or modification) stage,
> > and then mapped back, every time the environment is invoked.
> 
> > 
> > at the current step of evolution, those core files are not relocatable
> > in certain natively compiling lisp systems.
> 
> nor will they work if the sysadmin applies a security update and glibc
> or another library changes one page in size. Or changes the stack rlimit
> or .. or ..

Now, i figured out, there is a certain reasonable safety gap which works
for people, because the libraries depended on are well known.

What happens with AS randomisation, is that the variance is simply too
large. But what is more important, is that vendors do modifications
which change the amount of randomisation, which means that potentially
no MAP_FIXED is safe, generally.

Yes, there is uncertainty in both cases -- library variance or AS randomisation,
but the latter arguably crosses a practical manageability boundary.

> -- 
> if you want to mail me at work (you don't), use arjan (at) linux.intel.com
> Test the interaction between Linux and your BIOS via http://www.linuxfirmwarekit.org

regards, Samium Gromoff