Re: [PATCH v4 3/4] fanotify,audit: Allow audit to use the full permission event response

[Steve Grubb <sgrubb@redhat.com>]

On Wednesday, September 7, 2022 4:23:49 PM EDT Paul Moore wrote:
> On Wed, Sep 7, 2022 at 4:11 PM Steve Grubb <sgrubb@redhat.com> wrote:
> > On Wednesday, September 7, 2022 2:43:54 PM EDT Richard Guy Briggs wrote:
> > > > > Ultimately I guess I'll leave it upto audit subsystem what it wants
> > > > > to
> > > > > have in its struct fanotify_response_info_audit_rule because for
> > > > > fanotify subsystem, it is just an opaque blob it is passing.
> > > > 
> > > > In that case, let's stick with leveraging the type/len fields in the
> > > > fanotify_response_info_header struct, that should give us all the
> > > > flexibility we need.
> > > > 
> > > > Richard and Steve, it sounds like Steve is already aware of
> > > > additional
> > > > information that he wants to send via the
> > > > fanotify_response_info_audit_rule struct, please include that in the
> > > > next revision of this patchset.  I don't want to get this merged and
> > > > then soon after have to hack in additional info.
> > > 
> > > Steve, please define the type and name of this additional field.
> > 
> > Maybe extra_data, app_data, or extra_info. Something generic that can be
> > reused by any application. Default to 0 if not present.
> 
> I think the point is being missed ... The idea is to not speculate on
> additional fields, as discussed we have ways to handle that, the issue
> was that Steve implied that he already had ideas for "things" he
> wanted to add.  If there are "things" that need to be added, let's do
> that now, however if there is just speculation that maybe someday we
> might need to add something else we can leave that until later.

This is not speculation. I know what I want to put there. I know you want to 
pin it down to exactly what it is. However, when this started a couple years 
back, one of the concerns was that we're building something specific to 1 user 
of fanotify. And that it would be better for all future users to have a 
generic facility that everyone could use if they wanted to. That's why I'm 
suggesting something generic, its so this is not special purpose that doesn't 
fit any other use case.

-Steve