Re: [PATCH V3 0/3] Add support for session ID user filtering

[Paul Moore <pmoore@redhat.com>]

On Thursday, August 18, 2016 01:43:12 PM Richard Guy Briggs wrote:
> https://github.com/linux-audit/audit-kernel/wiki/RFE-Session-ID-User-Filter
> RFE Session ID User Filter
> 
> https://github.com/linux-audit/audit-kernel/issues/4
> RFE: add a session ID filter to the kernel's user filter
> 
> See also the set of userspace suport patches:
> 	Add support for sessionid user filters, sessionid_set and loginuid_set
> 	https://www.redhat.com/archives/linux-audit/2016-August/msg00005.html
> 	(userspace update expected to be posted 2016-08-18)
> and the test case:
> 	https://github.com/rgbriggs/audit-testsuite/tree/ghak4-test-for-sessionID-u
> ser-filter
> 
> This third patch is expected to have a merge conflict with:
> 	"audit: add exclude filter extension to feature bitmap"
> posted on 2016-08-18.
> 
> Richard Guy Briggs (3):
>   audit: add support for session ID user filter
>   audit: add AUDIT_SESSIONID_SET support
>   audit: add sessionid filter extension to feature bitmap
> 
>  include/linux/audit.h      |   10 ++++++++++
>  include/uapi/linux/audit.h |    6 +++++-
>  kernel/auditfilter.c       |    5 +++++
>  kernel/auditsc.c           |    6 ++++++
>  4 files changed, 26 insertions(+), 1 deletions(-)

In light of our current decision to drop the session ID "set" filter, I'm 
taking another look at these patches and Richard's comment to simply drop 
patch 2/3 and apply 1/3 and 3/3.

Richard, as I mentioned earlier, perhaps not clearly enough, I think we should 
put a check in audit_set_loginuid() to skip the (int)-1 value from appearing 
in session_id during normal operation.  In other words, roll/reset the value 
in session_id one value early so we don't run into problems with the (int)-1 
unset sentinel value.

-- 
paul moore
security @ redhat