Re: [RFC] Unify KVM kernel-space and user-space code into a single project

Daniel P. Berrange
2010-03-24T15:27:21Z

On Wed, Mar 24, 2010 at 04:01:37PM +0100, Joerg Roedel wrote:
> >> An approach like: "The files are owned and only readable by the same
> >> user that started the vm." might be a good start. So a user can measure
> >> its own guests and root can measure all of them.
> >
> > That's not how sVirt works. sVirt isolates a user's VMs from each
> > other, so if a guest breaks into qemu it can't break into other guests
> > owned by the same user.
>
> If a vm breaks into qemu it can access the host file system which is the
> bigger problem. In this case there is no isolation anymore. From that
> context it can even kill other VMs of the same user independent of a
> hypothetical /sys/kvm/.

No it can't. With sVirt every single VM has a custom security label and
the policy only allows it access to disks / files with a matching label,
and prevents it attacking any other VMs or processes on the host. THis
confines the scope of any exploit in QEMU to those resources the admin
has explicitly assigned to the guest.

Regards,
Daniel
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