[sr-dev] [kamailio/kamailio] Kamailio resets $ru in branch_route context, probably race condition (#2708)

[Henning Westerholt]

### Description

Kamailio resets the $ru in a branch_route context, probably due a race condition and/or bug.

Scenario:

- Calls is established and answered with 404
- Kamailio enters failure_route
- failure_route calls t_relay()
- branch_route is entered
- new branch is created with $ru = $ru;
- next operation trying to access content of the $ru fails:
Apr 13 11:44:39 proxy1 /usr/sbin/kamailio[2202]: ERROR: pv [pv_core.c:325]: pv_get_ruri_attr(): failed to parse the R-URI
 
### Troubleshooting

Happens on a production system, after upgrade from 5.2.x to 5.3.9. Research regarding similar bugs have not produced something useful so far.

#### Reproduction

Issue happens less than 10 times a day and so far could not be easily reproduced.

#### Debugging Data

Apr 13 11:44:39 proxy1 /usr/sbin/kamailio[2202]: NOTICE: 7e8bb2ba47f5ccc |-----> Failure Code 404<-
Apr 13 11:44:39 proxy1 /usr/sbin/kamailio[2202]: ERROR: *** cfgtrace:failure_route=[Failure] c=[/etc/kamailio/kamailio.cfg] l=1720 a=5 n=route
Apr 13 11:44:39 proxy1 /usr/sbin/kamailio[2202]: ERROR: *** cfgtrace:failure_route=[RELAY] c=[/etc/kamailio/kamailio.cfg] l=703 a=16 n=if
Apr 13 11:44:39 proxy1 /usr/sbin/kamailio[2202]: ERROR: *** cfgtrace:failure_route=[RELAY] c=[/etc/kamailio/kamailio.cfg] l=699 a=25 n=is_method
Apr 13 11:44:39 proxy1 /usr/sbin/kamailio[2202]: ERROR: *** cfgtrace:failure_route=[RELAY] c=[/etc/kamailio/kamailio.cfg] l=702 a=16 n=if
Apr 13 11:44:39 proxy1 /usr/sbin/kamailio[2202]: ERROR: *** cfgtrace:failure_route=[RELAY] c=[/etc/kamailio/kamailio.cfg] l=701 a=25 n=t_is_set
Apr 13 11:44:39 proxy1 /usr/sbin/kamailio[2202]: ERROR: *** cfgtrace:failure_route=[RELAY] c=[/etc/kamailio/kamailio.cfg] l=701 a=25 n=t_on_branch
Apr 13 11:44:39 proxy1 /usr/sbin/kamailio[2202]: ERROR: *** cfgtrace:failure_route=[RELAY] c=[/etc/kamailio/kamailio.cfg] l=707 a=16 n=if
Apr 13 11:44:39 proxy1 /usr/sbin/kamailio[2202]: ERROR: *** cfgtrace:failure_route=[RELAY] c=[/etc/kamailio/kamailio.cfg] l=703 a=25 n=is_method
Apr 13 11:44:39 proxy1 /usr/sbin/kamailio[2202]: ERROR: *** cfgtrace:failure_route=[RELAY] c=[/etc/kamailio/kamailio.cfg] l=706 a=16 n=if
Apr 13 11:44:39 proxy1 /usr/sbin/kamailio[2202]: ERROR: *** cfgtrace:failure_route=[RELAY] c=[/etc/kamailio/kamailio.cfg] l=705 a=25 n=t_is_set
Apr 13 11:44:39 proxy1 /usr/sbin/kamailio[2202]: ERROR: *** cfgtrace:failure_route=[RELAY] c=[/etc/kamailio/kamailio.cfg] l=707 a=25 n=t_on_branch_failure
Apr 13 11:44:39 proxy1 /usr/sbin/kamailio[2202]: ERROR: *** cfgtrace:failure_route=[RELAY] c=[/etc/kamailio/kamailio.cfg] l=720 a=16 n=if
Apr 13 11:44:39 proxy1 /usr/sbin/kamailio[2202]: ERROR: *** cfgtrace:failure_route=[RELAY] c=[/etc/kamailio/kamailio.cfg] l=711 a=25 n=is_method
Apr 13 11:44:39 proxy1 /usr/sbin/kamailio[2202]: ERROR: *** cfgtrace:failure_route=[RELAY] c=[/etc/kamailio/kamailio.cfg] l=714 a=16 n=if
Apr 13 11:44:39 proxy1 /usr/sbin/kamailio[2202]: ERROR: *** cfgtrace:failure_route=[RELAY] c=[/etc/kamailio/kamailio.cfg] l=713 a=25 n=t_is_set
Apr 13 11:44:39 proxy1 /usr/sbin/kamailio[2202]: ERROR: *** cfgtrace:failure_route=[RELAY] c=[/etc/kamailio/kamailio.cfg] l=713 a=25 n=t_on_failure
Apr 13 11:44:39 proxy1 /usr/sbin/kamailio[2202]: ERROR: *** cfgtrace:failure_route=[RELAY] c=[/etc/kamailio/kamailio.cfg] l=742 a=16 n=if
Apr 13 11:44:39 proxy1 /usr/sbin/kamailio[2202]: ERROR: *** cfgtrace:failure_route=[RELAY] c=[/etc/kamailio/kamailio.cfg] l=720 a=24 n=t_relay
Apr 13 11:44:39 proxy1 /usr/sbin/kamailio[2202]: ERROR: *** cfgtrace:branch_route=[MANAGE_BRANCH] c=[/etc/kamailio/kamailio.cfg] l=2142 a=16 n=if
Apr 13 11:44:39 proxy1 /usr/sbin/kamailio[2202]: ERROR: *** cfgtrace:branch_route=[MANAGE_BRANCH] c=[/etc/kamailio/kamailio.cfg] l=2135 a=63 n=assign
Apr 13 11:44:39 proxy1 /usr/sbin/kamailio[2202]: ERROR: *** cfgtrace:branch_route=[MANAGE_BRANCH] c=[/etc/kamailio/kamailio.cfg] l=2147 a=16 n=if
Apr 13 11:44:39 proxy1 /usr/sbin/kamailio[2202]: ERROR: *** cfgtrace:branch_route=[MANAGE_BRANCH] c=[/etc/kamailio/kamailio.cfg] l=2142 a=25 n=is_method
Apr 13 11:44:39 proxy1 /usr/sbin/kamailio[2202]: ERROR: *** cfgtrace:branch_route=[MANAGE_BRANCH] c=[/etc/kamailio/kamailio.cfg] l=2142 a=63 n=assign
Apr 13 11:44:39 proxy1 /usr/sbin/kamailio[2202]: ERROR: pv [pv_core.c:325]: pv_get_ruri_attr(): failed to parse the R-URI

#### Log Messages

See cfgtrace logging above.

#### SIP Traffic

Not easily to provide as its a productive system in a clustered setup.

### Possible Solutions

Ideas on how to further debug this error are welcome.

### Additional Information

* kamailio 5.3.9


-- 
You are receiving this because you are subscribed to this thread.
Reply to this email directly or view it on GitHub:
https://github.com/kamailio/kamailio/issues/2708
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.kamailio.org/pipermail/sr-dev/attachments/20210415/c147a00e/attachment.htm>