Re: [PATCH v2 00/10] Encrypted Hibernation

[Jason Gunthorpe]

On Tue, Sep 20, 2022 at 10:46:48AM +0200, Pavel Machek wrote:
> Hi!
> 
> > We are exploring enabling hibernation in some new scenarios. However,
> > our security team has a few requirements, listed below:
> > 1. The hibernate image must be encrypted with protection derived from
> >    both the platform (eg TPM) and user authentication data (eg
> >    password).
> > 2. Hibernation must not be a vector by which a malicious userspace can
> >    escalate to the kernel.
> 
> Why is #2 reasonable requirement?

These days with kernel lockdown we don't allow userspace to enter the
kernel

> We normally allow userspace with appropriate permissions to update the
> kernel, for example.

And in a lockdown secure boot environment only a signed kernel can be
booted in the first place.

A series like this is effectively carrying the secure boot trust
across the hibernation

Jason