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Subject: Re: [PATCH v2 2/3] ima: don't ignore INTEGRITY_UNKNOWN EVM status
From:   James Bottomley <James.Bottomley@HansenPartnership.com>
To:     Roberto Sassu <roberto.sassu@huawei.com>,
        Mimi Zohar <zohar@linux.ibm.com>, dmitry.kasatkin@huawei.com,
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Date:   Tue, 04 Jun 2019 11:57:17 +0300
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On Mon, 2019-06-03 at 16:44 +0200, Roberto Sassu wrote:
> On 6/3/2019 4:31 PM, James Bottomley wrote:
> > On Mon, 2019-06-03 at 16:29 +0200, Roberto Sassu wrote:
[...]
> > > How would you prevent root in the container from updating
> > > security.ima?
> > 
> > We don't.  We only guarantee immutability for unprivileged
> > containers, so root can't be inside.
> 
> Ok.
> 
> Regarding the new behavior, this must be explicitly enabled by adding
> ima_appraise=enforce-evm or log-evm to the kernel command line.
> Otherwise, the current behavior is preserved with this patch. Would
> this be ok?

Sure, as long as it's an opt-in flag, meaning the behaviour of my
kernels on physical cloud systems doesn't change as I upgrade them, I'm
fine with that.

James