Re: [PATCH 1/7] ima: on soft reboot, restore the measurement list

From: Mimi Zohar
Date: Tue Aug 09 2016 - 09:01:45 EST


On Tue, 2016-08-09 at 20:59 +1000, Michael Ellerman wrote:
> Mimi Zohar <zohar@xxxxxxxxxxxxxxxxxx> writes:
>
> > diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h
> > index b5728da..84e8d36 100644
> > --- a/security/integrity/ima/ima.h
> > +++ b/security/integrity/ima/ima.h
> > @@ -102,6 +102,13 @@ struct ima_queue_entry {
> > };
> > extern struct list_head ima_measurements; /* list of all measurements */
> >
> > +/* Some details preceding the binary serialized measurement list */
> > +struct ima_kexec_hdr {
> > + unsigned short version;
> > + unsigned long buffer_size;
> > + unsigned long count;
> > +} __packed;
> > +
>
> Am I understanding it correctly that this structure is passed between kernels?

Yes, the header prefixes the measurement list, which is being passed on
the same computer to the next kernel. Could the architecture (eg.
LE/BE) change between soft re-boots?

> If so it's an ABI and should use types with well defined sizes, as if it was
> going out to userspace, shouldn't it?

Ok

Mimi