exclude filter action ignored?

[Richard Guy Briggs]

Hi Steve,

Can you confirm that the exclude filter action parameter is ignored?  I
can't find any evidence in the kernel or in userspace that the action
value is actually honoured.  In fact, looking at the manpage for
auditctl(8), the wording of the action contradicts the intuitive meaning
of that filter name.  And as a matter of fact, I find discussion of it
here:
	https://www.redhat.com/archives/linux-audit/2005-October/msg00020.html


In auditctl, setopt() calls audit_rule_setup() which calls lookup_filter() and
lookup_action(), then calls audit_rule_fieldpair_data() none of which
check when parsing the AUDIT_MSGTYPE field.

During rule addition, in kernel/auditfilter.c:audit_rule_change() and
callees AUDIT_FILTER_TYPE is never checked for either action but simply
copied.

When called from audit_log_start() in
kernel/auditfilter.c:audit_filter_type(), the state is never checked, so
either AUDIT_NEVER or AUDIT_ALWAYS actions gives the same result which
is to ignore that message type.


- RGB

--
Richard Guy Briggs <rgb at redhat.com>
Kernel Security Engineering, Base Operating Systems, Red Hat
Remote, Ottawa, Canada
Voice: +1.647.777.2635, Internal: (81) 32635