[PATCH v3] audit: Turn off TIF_SYSCALL_AUDIT when there are no rules

[Steve Grubb]

On Monday, February 10, 2014 11:01:36 AM Andy Lutomirski wrote:
> >> And I still think this needs more changes. Once again, I do not think
> >> that, say, __audit_log_bprm_fcaps() should populate context->aux if
> >> !TIF_SYSCALL_AUDIT, this list can grow indefinitely. Or
> >> __audit_signal_info()...
> >> 
> >> Perhaps __audit_syscall_exit() should also set context->dummy?
> > 
> > That would work.
> > 
> > I'm still torn between trying to make it possible for things like
> > __audit_log_bprm_fcaps to start a syscall audit record in the middle
> > of a syscall or to just try to tighten up the current approach to the
> > point where it will work correctly.
> 
> This is worse than I thought.  Things like signal auditing can enter
> the audit system from outside of a syscall.  I don't think there's
> currently any way to tell whether you're in a syscall (when
> TIF_SYSCALL_AUDIT is clear) so getting this to work right would
> require arch help.
> 
> I'll ask what people on the Fedora list think about just changing the
> default to -t task,never.

I can't recall ever seeing the task filter used in real life. But assuming you 
wanted to audit no tasks, what is the difference between using that filter and 
never setting audit_enable in the first place?

-Steve