Re: ntp audit spew.
On Mon, Sep 23, 2019 at 11:50 AM Dave Jones <davej(a)codemonkey.org.uk> wrote:
I have some hosts that are constantly spewing audit messages like so:
[46897.591182] audit: type=1333 audit(1569250288.663:220): op=offset old=2543677901372
new=2980866217213
[46897.591184] audit: type=1333 audit(1569250288.663:221): op=freq old=-2443166611284
new=-2436281764244
[48850.604005] audit: type=1333 audit(1569252241.675:222): op=offset old=1850302393317
new=3190241577926
[48850.604008] audit: type=1333 audit(1569252241.675:223): op=freq old=-2436281764244
new=-2413071187316
[49926.567270] audit: type=1333 audit(1569253317.638:224): op=offset old=2453141035832
new=2372389610455
[49926.567273] audit: type=1333 audit(1569253317.638:225): op=freq old=-2413071187316
new=-2403561671476
This gets emitted every time ntp makes an adjustment, which is apparently very frequent
on some hosts.
Audit isn't even enabled on these machines.
# auditctl -l
No rules
[NOTE: added linux-audit to the CC line]
There is an audit mailing list, please CC it when you have audit
concerns/questions/etc.
What happens when you run 'auditctl -a never,task'? That *should*
silence those messages as the audit_ntp_log() function has the
requisite audit_dummy_context() check. FWIW, this is the distro
default for many (most? all?) distros; for example, check
/etc/audit/audit.rules on a stock Fedora system. A more selective
configuration could simply exclude the TIME_ADJNTPVAL record (type
1333) from the records that the kernel emits.
We could also add a audit_enabled check at the top of
audit_ntp_log()/__audit_ntp_log(), but I imagine some of that depends
on the various security requirements (they can be bizzare and I can't
say I'm up to date on all those - Steve Grubb should be able to
comment on that).
--
paul moore
www.paul-moore.com