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

From: Jason Gunthorpe
Date: Mon Mar 12 2018 - 19:05:13 EST


On Mon, Mar 12, 2018 at 06:58:45PM -0400, Mimi Zohar wrote:
> 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.

That doesn't help distros, which is the main point of the complaint
with this scheme :)

Jaason