Re: [PATCH] ima: add a new CONFIG for loading arch-specific policies

Heiko Carstens
2020-03-02T21:21:17Z

On Mon, Mar 02, 2020 at 09:56:58AM -0500, Mimi Zohar wrote:
> On Mon, 2020-03-02 at 15:52 +0100, Ard Biesheuvel wrote:
> > On Mon, 2 Mar 2020 at 15:48, Mimi Zohar <zohar@linux.ibm.com> wrote:
> > > > diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
> > > > index beea77046f9b..cafa66313fe2 100644
> > > > --- a/arch/x86/Kconfig
> > > > +++ b/arch/x86/Kconfig
> > > > @@ -230,6 +230,7 @@ config X86
> > > > select VIRT_TO_BUS
> > > > select X86_FEATURE_NAMES if PROC_FS
> > > > select PROC_PID_ARCH_STATUS if PROC_FS
> > > > + select IMA_SECURE_AND_OR_TRUSTED_BOOT if EFI
> > >
> > > Not everyone is interested in enabling IMA or requiring IMA runtime
> > > policies. With this patch, enabling IMA_ARCH_POLICY is therefore
> > > still left up to the person building the kernel. As a result, I'm
> > > seeing the following warning, which is kind of cool.
> > >
> > > WARNING: unmet direct dependencies detected for
> > > IMA_SECURE_AND_OR_TRUSTED_BOOT
> > > Depends on [n]: INTEGRITY [=y] && IMA [=y] && IMA_ARCH_POLICY [=n]
> > > Selected by [y]:
> > > - X86 [=y] && EFI [=y]
> > >
> > > Ard, Michael, Martin, just making sure this type of warning is
> > > acceptable before upstreaming this patch. I would appreciate your
> > > tags.
> > >
> >
> > Ehm, no, warnings like these are not really acceptable. It means there
> > is an inconsistency in the way the Kconfig dependencies are defined.
> >
> > Does this help:
> >
> > select IMA_SECURE_AND_OR_TRUSTED_BOOT if EFI && IMA_ARCH_POLICY
> >
> > ?
>
> Yes, that's fine for x86.  Michael, Martin, do you want something
> similar or would you prefer actually selecting IMA_ARCH_POLICY?

For s390 something like

select IMA_SECURE_AND_OR_TRUSTED_BOOT if IMA_ARCH_POLICY

should be fine.

Thanks,
Heiko