Re: [coLinux-devel] Re: Posix Subsystem for ReactOS - Project 2010

[Dan A. <da...@gm...>]

On Thu, Jan 29, 2004 at 01:26:52AM +0000, Nuno Silva wrote:
> 
> I can be wrong, but I think that coLinux doesn't play in this field 
> (virtual servers for *untrusted* root users) because, unlike UML or XEN, 
> the "virtual" linux can bring the host down.
> 
> Disabling interrupts and entering and endless loop or /bin/cat 
> /dev/random > /proc/kmem or some other havoc will do this...
> 
> Reality check:
> I'm I right?

It is possible to take some measurements in coLinux that will allow it to
crash peacefully without hurting the host OS. For example, on the first
Oops, switch back to the host and shut it down.

There are slims chances that memory corruption inside coLinux would hurt the
host OS since all memory that is mapped inside coLinux is physical memory
that was allocated specially for it. However, if you deliberately overwrite
page tables in coLinux and cause them to map host physical memory that was 
unallocated for it *and* then corrupt that memory, it will bring down the
host.

Another way to do so is to specifically corrupt the passage page.

Or as you said, you can upload a kernel module under coLinux which disables
intrrupts and enters an endless loop.

-- 
Dan Aloni
da...@gm...