Re: [PATCH] security: Fix IMA Kconfig for dependencies on ARM64

From: Mimi Zohar
Date: Mon Mar 12 2018 - 18:59:01 EST


On Mon, 2018-03-12 at 15:59 -0600, Jason Gunthorpe wrote:
> On Mon, Mar 12, 2018 at 05:53:18PM -0400, Mimi Zohar wrote:
>
> > Using Kconfig to force the TPM to be builtin is not required, but
> > helpful. ÂUsers interested in IMA-measurement could configure the TPM
> > as builtin themselves. ÂWithout the TPM builtin, IMA goes into TPM-
> > bypass mode.
>
> This issues, broadly speaking, we have lots of TPM drivers, selecting
> only some to actually support IMA shows we have some kind of problem
> here.

True, IMA is not selecting the older TPM vendor specific modules, but
only the newer TPM_TIS and now TPM_CRB modules. ÂThat doesn't imply
that IMA only supports some TPMs. ÂIt means that by default, these
TPMs are builtin. ÂAnyone building a kernel, can select the vendor
specific TPM to be builtin.

Mimi