Re: ntp audit spew.

On Tue, Sep 24, 2019 at 9:50 AM Richard Guy Briggs <rgb(a)redhat.com&gt; wrote: > On 2019-09-23 23:01, Paul Moore wrote: > > On Mon, Sep 23, 2019 at 5:00 PM Richard Guy Briggs <rgb(a)redhat.com&gt; wrote: > > > On 2019-09-23 12:14, Paul Moore wrote: > > > > On Mon, Sep 23, 2019 at 11:50 AM Dave Jones <davej(a)codemonkey.org.uk&gt; 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 > > > > > > Odd. It appears these two above should have the same serial number and > > > should be accompanied by a syscall record. It appears that it has no > > > context to update to connect the two records. Is it possible it is not > > > being called in a task context? If that were the case though, I'd > > > expect audit_dummy_context() to return 1... > > > > Yeah, I'm a little confused with these messages too. As you pointed > > out, the different serial numbers imply that the audit_context is NULL > > and if the audit_context is NULL I would have expected it to fail the > > audit_dummy_context() check in audit_ntp_log(). I'm looking at this > > with tired eyes at the moment, so I'm likely missing something, but I > > just don't see it right now ... > > > > What is even more confusing is that I don't see this issue on my test systems. > > > > > Checking audit_enabled should not be necessary but might fix the > > > problem, but still not explain why we're getting these records. > > > > I'd like to understand why this is happening before we start changing the code. > > Absolutely. > > This looks like a similar issue to the AUDIT_NETFILTER_CFG issue where > we get a lone record unconnected to a syscall when one of the netfilter > table initialization (ipv4 filter) is linked into the kernel rather than > compiled as a module, so it is run in kernel context at boot rather than > in user context as a module load later. This is why I ask if it is > being run by a kernel thread rather than a user task, perhaps using a > syscall function call internally. I don't see where in the code that could happen, but I agree that it looks like it; maybe I'm just missing a code path somewhere. Is anyone else seeing these records? Granted my audit test systems are running chrony, not ntp, but the syscalls/behaviors should be similar and I can't seem to recreate this.