Messages in this thread | | | From | Andy Lutomirski <> | Date | Sat, 1 Feb 2014 18:51:56 -0800 | Subject | Re: Why is syscall auditing on with no rules? |
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On Sat, Feb 1, 2014 at 6:32 PM, Andy Lutomirski <luto@amacapital.net> wrote: > On a stock Fedora installation: > > $ sudo auditctl -l > No rules > > Nonetheless TIF_SYSCALL_AUDIT is set and the __audit_syscall_entry and > __audit_syscall_exit account for >20% of syscall overhead according to > perf. > > This sucks. Unless I'm missing something, syscall auditing is *off*. > > How hard would it be to arrange for TIF_SYSCALL_AUDIT to be cleared > when there are no syscall rules? > > (This is extra bad in kernels before 3.13, where the clear call for > TIF_SYSCALL_AUDIT was completely missing.)
The current code seems to have really odd effects. For example, processes that are created before the very first auditctl -e 1 (or auditd) invocation will never be subject to syscall auditing. But auditctl -e 1; auditctl -e 0 will cause all subsequently started processes to have audit contexts allocated and therefore to be subject to syscall auditing.
I doubt that this behavior is considered desirable.
--Andy
> > --Andy
-- Andy Lutomirski AMA Capital Management, LLC
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