Systemd Journald and audit logging causing journal issues

Tue Oct 17 15:25:53 UTC 2017

Hello,

I apologize for the late reply...just found the message.

On Monday, October 2, 2017 1:30:19 PM EDT Brad Zynda wrote:
> I am sending along an issue brought to the systemd-journald dev list
> initially:
> 
> On 10/02/2017 11:40 AM, Lennart Poettering wrote:
> > On Mo, 02.10.17 11:25, Brad Zynda (bradley.v.zynda at nasa.gov) wrote:
> >> Sep 28 13:50:03 server systemd-journal[565]: Suppressed 73244 messages
> >> from /system.slice/auditd.service
> > 
> > The question is: why does auditd even log to the journal?

It doesn't. I have had many arguments with the systemd people about polluting 
syslog with audit events. If we wanted audit events there, we would have wrote 
them there. The journal is listening on a multicast audit socket that was 
created just for them and using a posix capability that was created just for 
them. And journal also turns on auditing even if you didn't want it. In short, 
they have, with intention, created your problem.

> >> Now we are required to have full audit rules and does this look like at
> >> rate limiting issue or an issue of journal not able to handle the
> >> traffic to logging?
> > 
> > journald detected that it got flooded with too many messages in too
> > short a time from auditd. if this happens then something is almost
> > certainly off with auditd, as auditd is not supposed to flood journald
> > with messages, after all it maintains its own auditing log database.

No...that's the way it works. If you want the audit stream, you have to be 
able to handle it. My suggestion is that we have a separation of duties. 
Auditd has audit events, journal has syslog. Besides, mixing audit and syslog 
data means the security officer and system admin roles have been combined. I 
think there is an audit.socket unit file that can be masked.

> > Please ping the auditd folks for help

They created the problem of audit events in syslog. That said, its been my 
experience that whenever you get lots of events, there may be something wrong 
with your rules.

The normal technique to figure out what wrong is to run aureport --summary 
--key during the time range of the flood to see what rule is triggering. Then 
we can look at that rule to see if there's something wrong with it.

More below...

> Hey Everyone,
> 
> Not sure if this is a bug so:
> 
> systemctl status -l systemd-journald.service
> ● systemd-journald.service - Journal Service
>    Loaded: loaded (/usr/lib/systemd/system/systemd-journald.service;
> static; vendor preset: disabled)
>    Active: active (running) since Tue 2017-09-26 20:01:16 UTC; 5 days ago
>      Docs: man:systemd-journald.service(8)
>            man:journald.conf(5)
>  Main PID: 565 (systemd-journal)
>    Status: "Processing requests..."
>    CGroup: /system.slice/systemd-journald.service
>            └─565 /usr/lib/systemd/systemd-journald
> 
> Sep 28 13:50:03 server systemd-journal[565]: Suppressed 73244 messages
> from /system.slice/auditd.service
> Sep 28 13:51:03 server systemd-journal[565]: Suppressed 98979 messages
> from /system.slice/auditd.service
> Sep 28 13:52:03 server systemd-journal[565]: Suppressed 109433 messages
> from /system.slice/auditd.service
> Sep 28 13:53:03 server systemd-journal[565]: Suppressed 99788 messages
> from /system.slice/auditd.service
> Sep 28 13:54:03 server systemd-journal[565]: Suppressed 111605 messages
> from /system.slice/auditd.service
> Sep 28 13:55:03 server systemd-journal[565]: Suppressed 111591 messages
> from /system.slice/auditd.service
> Sep 28 13:56:03 server systemd-journal[565]: Suppressed 107947 messages
> from /system.slice/auditd.service
> Sep 28 13:57:51 server systemd-journal[565]: Suppressed 32760 messages
> from /system.slice/auditd.service
> Sep 28 17:21:40 server systemd-journal[565]: Suppressed 210 messages
> from /system.slice/auditd.service
> Oct 01 02:16:01 server systemd-journal[565]: Suppressed 1333 messages
> from /system.slice/auditd.service
> 
> journalctl --verify
> PASS: /run/log/journal/d28b0080ffe0432a974f36e4fb4bfa9b/system.journal
> PASS:
> /run/log/journal/d28b0080ffe0432a974f36e4fb4bfa9b/system at 0d49221d68d04ef0b95
> d8203c5e96a46-000000000097f6c7-0005596b745b4d1c.journal PASS:
> /run/log/journal/d28b0080ffe0432a974f36e4fb4bfa9b/system at 0d49221d68d04ef0b95
> d8203c5e96a46-000000000096a587-00055966f35ae59a.journal PASS:
> /run/log/journal/d28b0080ffe0432a974f36e4fb4bfa9b/system at 0d49221d68d04ef0b95
> d8203c5e96a46-00000000009554f1-000559629c4cdb7e.journal PASS:
> /run/log/journal/d28b0080ffe0432a974f36e4fb4bfa9b/system at 0d49221d68d04ef0b95
> d8203c5e96a46-0000000000940591-0005595e1811a2d1.journal PASS:
> /run/log/journal/d28b0080ffe0432a974f36e4fb4bfa9b/system at 0d49221d68d04ef0b95
> d8203c5e96a46-000000000092b500-00055959f2de5ede.journal PASS:
> /run/log/journal/d28b0080ffe0432a974f36e4fb4bfa9b/system at 0d49221d68d04ef0b95
> d8203c5e96a46-0000000000916479-0005595573137b74.journal PASS:
> /run/log/journal/d28b0080ffe0432a974f36e4fb4bfa9b/system at 0d49221d68d04ef0b95
> d8203c5e96a46-0000000000901337-00055950d80cc3d8.journal PASS:
> /run/log/journal/d28b0080ffe0432a974f36e4fb4bfa9b/system at 0d49221d68d04ef0b95
> d8203c5e96a46-00000000008ec2fb-0005594cad14b07a.journal PASS:
> /run/log/journal/d28b0080ffe0432a974f36e4fb4bfa9b/system at 0d49221d68d04ef0b95
> d8203c5e96a46-00000000008d7373-0005594838683e58.journal PASS:
> /run/log/journal/d28b0080ffe0432a974f36e4fb4bfa9b/system at 0d49221d68d04ef0b95
> d8203c5e96a46-00000000008c238e-00055943fe2072e3.journal PASS:
> /run/log/journal/d28b0080ffe0432a974f36e4fb4bfa9b/system at 0d49221d68d04ef0b95
> d8203c5e96a46-00000000008ad1d9-0005593ff64a4f69.journal PASS:
> /run/log/journal/d28b0080ffe0432a974f36e4fb4bfa9b/system at 0d49221d68d04ef0b95
> d8203c5e96a46-0000000000897f32-0005593e18c5758b.journal
> 
> 
> journalctl --disk-usage
> Archived and active journals take up 1.1G on disk.
> 
> 
> Initially we saw:
> 16733 PATH
> 5070 SYSCALL
> 5024 CWD
> 3765 AVC
> 323 CRYPTO_KEY_USER
> 223 USER_START
> 222 USER_ACCT
> 222 CRED_ACQ
> 220 LOGIN
> 220 CRED_REFR
> 218 USER_END
> 218 CRED_DISP
> 46 USER_LOGIN
> 12 EXECVE
> 4 USER_AUTH
> 2 CRYPTO_SESSION
> 1 USER_ROLE_CHANGE
> 1 USER_CMD
> 1 SERVICE_STOP
> 1 SERVICE_START
> 1 BPRM_FCAPS
> 
> so we blocked type PATH in audit.rules

This is not the right thing to do. If a security officer asks what is being 
accessed, you got rid of the information. The right thing is to figure out 
which rule is being hit and see if something is wrong with it. For example, I 
have seen people do this:

-a always,exit -S open,openat -F exit=-EPERM

The problem is that they did not restrict the rule an architecture and they 
were getting lots of events for the wrong syscall. I've also seen people add 
-F success 0 to an open syscall. This also results in a large number of 
events.

So, I'd recommend making sure all rules have keys added and the running the 
key summary report to see what rule needs inspection.

If you find the rule that's causing the problem and you want an opinion, send 
it to the mail list.

-Steve

> But we are still seeing 100K of dropped/suppressed messages.
> 
> Note: systemloglevel = INFO
> 
> Centos 7 1708 3.10.0-693.2.2.el7.x86_64
> 
> systemd.x86_64                      219-42.el7_4.1
> 
> 
> Now we are required to have full audit rules and does this look like at
> rate limiting issue or an issue of journal not able to handle the
> traffic to logging?
>
> Error we are seeing from services that have silently failed, in this
> case glassfish..
> 
> systemctl status -l glassfish
> ● glassfish.service - SYSV: GlassFish start and stop  daemon
>    Loaded: loaded (/etc/rc.d/init.d/glassfish; bad; vendor preset: disabled)
> Active: active (exited) since Tue 2017-09-26 20:01:36 UTC; 5 days ago Docs:
> man:systemd-sysv-generator(8)
>   Process: 1328 ExecStart=/etc/rc.d/init.d/glassfish start (code=exited,
> status=0/SUCCESS)
> 
> Warning: Journal has been rotated since unit was started. Log output is
> incomplete or unavailable.
> 
> Eventually glassfish will fail but it wont kill the service so we never
> get an nms service down trap from the OID.
> 
> Please let me know if further info is needed or if certain limits need
> to be adjusted.
> 
> Thanks,
> Brad Zynda
> 
> 
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