Re: [PATCH] docs: security: Confidential computing intro and threat model

From: Michael S. Tsirkin
Date: Thu Apr 27 2023 - 13:21:01 EST


On Thu, Apr 27, 2023 at 09:18:08AM -0400, James Bottomley wrote:
> I think the problem is that the tenor of the document is that the CSP
> should be seen as the enemy of the tenant. Whereas all CSP's want to be
> seen as the partner of the tenant (admittedly so they can upsell
> services). In particular, even if you adopt (b) there are several
> reasons why you'd use confidential computing:
>
> 1. Protection from other tenants who break containment in the cloud.
> These tenants could exfiltrate data from Non-CoCo VMs, but likely
> would be detected before they had time to launch an attack using
> vulnerabilities in the current linux device drivers.
> 2. Legal data security.  There's a lot of value in a CSP being able
> to make the legal statement that it does not have access to a
> customer data because of CoCo.
> 3. Insider threats (bribe a CSP admin employee).  This one might get
> as far as trying to launch an attack on a CoCo VM, but having
> checks at the CSP to detect and defeat this would work instead of
> every insider threat having to be defeated inside the VM.

And generally, all these are instances of adopting a zero trust
architecture, right? Many CSPs have no need to access VM memory
so they would rather not have the ability.

--
MST