Re: [PATCH v8 03/19] ima: Move policy related variables into ima_namespace

[Christian Brauner <brauner@kernel.org>]

On Thu, Jan 13, 2022 at 03:26:51PM -0500, Mimi Zohar wrote:
> Hi Stefan,
> 
> On Tue, 2022-01-04 at 12:04 -0500, Stefan Berger wrote:
> > From: Stefan Berger <stefanb@linux.ibm.com>
> > 
> > Move variables related to the IMA policy into the ima_namespace. This way
> > the IMA policy of an IMA namespace can be set and displayed using a
> > front-end like SecurityFS.
> > 
> > Implement ima_ns_from_file() to get the IMA namespace via the user
> > namespace of the SecurityFS superblock that a file belongs to.
> > 
> > To get the current ima_namespace use get_current_ns() when a function
> > that is related to a policy rule is called. In other cases where functions
> > are called due file attribute modifications, use init_ima_ns, since these
> > functions are related to IMA appraisal and changes to file attributes are
> > only relevant to the init_ima_ns until IMA namespaces also support IMA
> > appraisal. In ima_file_free() use init_ima_ns since in this case flags
> > related to file measurements may be affected, which is not supported in
> > IMA namespaces, yet.
> > 
> > Signed-off-by: Stefan Berger <stefanb@linux.ibm.com>
> 
> Please split this patch into "ima: pass through ima namespace", or some
> other name,  and "ima: Move policy related variables into
> ima_namespace".  The other option is to combine the "pass through ima
> namespace" with the 2nd patch, like Christian's example.

I was just about to comment something similar on 02/19.

I would also not introduce get_current_ns(). It's simply more honest and
if &init_ima_ns is used everywhere until multiple namespaces can
actually exists.