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

From: "Michael S. Tsirkin" <mst@redhat.com>
To: James Bottomley <jejb@linux.ibm.com>
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Subject: Re: [PATCH] docs: security: Confidential computing intro and threat model
Date: Thu, 27 Apr 2023 13:19:52 -0400	[thread overview]
Message-ID: <20230427131542-mutt-send-email-mst@kernel.org> (raw)
In-Reply-To: <efda0be02fb0b5bf23aec11b5398d20908a821ba.camel@linux.ibm.com>

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