On Sat, Feb 1, 2014 at 6:32 PM, Andy Lutomirski <luto(a)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