A wasn't even thinking about testing for calling current ruleset since
it seems overly complicated.
Just a simple counter increased by one on every call/call_indirect and a
check whether or not it exceeds a given (configurable?) limit.
But then again - as I said - my use case is quite complicated and the
whole first mail was more of a way to archive the problem since someone
might encounter it on their own and not be able to pinpont the cause
quickly. The case of ruleset looping might be so rare that it's not
worth adding such check.
Best regards
MK
On 16.07.2021 19:15, David Lang wrote:
a simple test to prevent calling the current ruleset seems like it
ould be doable, but when you start talking chains of rulesets,
tracking the full depth to prevent more indirect loops may be more
difficult (or it may not be, Rainer would need to comment on this)
I think it would be reasonable to have the default be 'no recursion',
only allow calling a ruleset once, with a possible config option to
allow a configurable recursion depth.
when the depth is exceeded, I would have rsyslog log a message and
treat the call as a noop (the other possible option would be to treat
it as a stop), and it would be fantastic if there was a 'bad logs'
file that could be defined that we could have messages that trigger
bad things like this written to (in json format with all metadata,
etc) for debugging purposes
David Lang
On Fri, 16 Jul 2021, Mariusz Kruk via rsyslog wrote:
Date: Fri, 16 Jul 2021 14:23:32 +0200
From: Mariusz Kruk via rsyslog <[email protected]>
To: [email protected]
Cc: Mariusz Kruk <[email protected]>
Subject: [rsyslog] Segfault after recursion too deeply
Hi there.
Just as an interesting fact, after a recent change in configuration I
started receiving segfaults.
segfault at 7fb3ed112ff8 ip 00007fb4323946fe sp 00007fb3ed113000
error 6 in libfastjson.so.4.2.0[7fb432392000+a000]
After some digging I pinpointed the culprit (but I must say that the
origin of the segfault - libfastjson was puzzling here).
My configuration is relatively complicated (over 6,5k lines,
including lookups) so I won't go into much detail here but the main
thing is that in the course of message processing I do a lookup on a
specific part of the message to decide which ruleset to run.
Something like this:
ruleset(name="do_a_lookup")
{
set $.ruleset = lookup ("hostname-to-ruleset", $fromhost-ip);
call_indirect $.ruleset;
}
And unfortunately for some messages my lookup returned a
"do_a_lookup" ruleset name to run again and again (of course, since
between subsequent calls the origin of the message didn't change).
It was definitely my mistake and I was quite lucky that it occured
quite quickly after I introduced the change (if it happened with
messages I get just once a day or even once a week, it'd be very hard
to troubleshoot).
You might want to think about a ruleset call "depth counter" in order
to at least emit a warning if the recursion gets too deep. But then
again - my case is very unusual and it might not be worth introducing
such change into the code.
Best regards
_______________________________________________
rsyslog mailing list
https://lists.adiscon.net/mailman/listinfo/rsyslog
http://www.rsyslog.com/professional-services/
What's up with rsyslog? Follow https://twitter.com/rgerhards
NOTE WELL: This is a PUBLIC mailing list, posts are ARCHIVED by a myriad of
sites beyond our control. PLEASE UNSUBSCRIBE and DO NOT POST if you DON'T LIKE
THAT.
