[userspace PATCH v2 0/2] Add support for loginuid_set

[Paul Moore]

On Tue, Oct 11, 2016 at 4:50 PM, Steve Grubb <sgrubb at redhat.com> wrote:
> On Tuesday, October 11, 2016 4:42:58 PM EDT Paul Moore wrote:
>> On Tue, Oct 11, 2016 at 3:22 PM, Steve Grubb <sgrubb at redhat.com> wrote:
>> > On Tuesday, October 11, 2016 2:27:54 PM EDT Richard Guy Briggs wrote:
>> >> On 2016-10-11 12:40, Steve Grubb wrote:
>> >> > On Monday, October 10, 2016 5:10:39 PM EDT Paul Moore wrote:
>> >> > > On Mon, Oct 10, 2016 at 1:24 PM, Steve Grubb <sgrubb at redhat.com>
> wrote:
>> >> > > > On Thursday, August 18, 2016 2:18:55 PM EDT Richard Guy Briggs
> wrote:
>> >> > > >> loginuid_set support should have been added to userspace when it
>> >> > > >> was
>> >> > > >> added to the kernel around v3.10.  Add it before we do similar for
>> >> > > >> sessionID and sessionID_set.
>> >> > > >
>> >> > > > If this were accepted, how would this change writing rules? IOW,
>> >> > > > can
>> >> > > > you
>> >> > > > give an example rule so we can see what this looks like?
>> >> > >
>> >> > > We have a RFE feature page which documents some rule examples:
>> >> > >
>> >> > > *
>> >> > > https://github.com/linux-audit/audit-kernel/wiki/RFE-Session-ID-User-> >> > > Fil
>> >> > > ter
>> >> >
>> >> > OK, thanks. This is helpful. So, what is the difference between these
>> >> > rules?
>> >> >
>> >> > -a always,exit -F path=/tmp/sessionid_test -F loginuid=-1
>> >> >
>> >> > -a always,exit -F path=/tmp/sessionid_set_test -F loginuid_set=0
>> >>
>> >> The only difference is one flag in the kernel to indicate how it was
>> >> invoked to be able to report when queried exactly the same way it was
>> >> invoked, but there is no difference in the actual behaviour of the
>> >> filter.  This was added because of your report that "f24=0" was reported
>> >> instead of loginuid_set=0 for backwards compatibility.
>> >
>> > OK. Generally its bad to have 2 ways to do the same thing. People use SCAP
>> > content to check system configurations. If there's two ways to do the same
>> > thing, then someone can accidentally choose the wrong way and fail their
>> > scan. We run into this in the past where we allowed -a exit,always and -a
>> > always,exit. All the rules had to be reworked to be consistent.
>> > Therefore, I would recommend not using the loginuid_set option. We still
>> > get questions about -w /path/file -p wa  vs -a always,exit -F
>> > path=/path/file -F perm=wa. But that one is so deeply embedded that it
>> > should not be fixed.
>> >
>> >> Going forward, the implementation of the sessionid_set field (which
>> >> works similarly) will not allow an unset value of sessionid since these
>> >> are a new addition that didn't need to accomodate backward
>> >> compatibility.
>> >
>> > As long as we can trigger on sessionid=-1, then we are fine.
>>
>> Wait a minute ... what happened to the loginuid_set patches?  Didn't
>> those get merged to userspace?
>
> I'm reviewing this patch set for merging now that we are past all the 2.6 bug
> fixing.

Ah, nevermind ... I confused loginuid and sessionid, sorry about the confusion.

Anyway, I thought the desire for having a dedicated "is the loginuid
value set?" filter came from userspace?  If not, where did this
requirement come from?

-- 
paul moore
security @ redhat