Bug 923113

Summary:	Potential crash during startup/reload if global configuration options are set
Product:	Red Hat Enterprise Linux 6	Reporter:	Petr Spacek <pspacek>
Component:	bind-dyndb-ldap	Assignee:	Petr Spacek <pspacek>
Status:	CLOSED ERRATA	QA Contact:	Namita Soman <nsoman>
Severity:	urgent	Docs Contact:
Priority:	urgent
Version:	6.4	CC:	chhudson, dpal, lmiksik, mkosek, ovasik, pspacek
Target Milestone:	rc	Keywords:	ZStream
Target Release:	---
Hardware:	Unspecified
OS:	Unspecified
Whiteboard:
Fixed In Version:		Doc Type:	Bug Fix
Doc Text:	The bind-dyndb-ldap plug-in processed settings too early, which led to the daemon terminating unexpectedly with a segmentation fault during startup or reload. The bind-dyndb-ldap plug-in has been fixed to process its options later, and so, no longer crashes during startup or reload.	Story Points:	---
Clone Of:		Environment:
Last Closed:	2013-11-21 12:11:05 UTC	Type:	---
Regression:	---	Mount Type:	---
Documentation:	---	CRM:
Verified Versions:		Category:	---
oVirt Team:	---	RHEL 7.3 requirements from Atomic Host:
Cloudforms Team:	---	Target Upstream Version:
Embargoed:
Bug Depends On:
Bug Blocks:	883504, 928429

Description Petr Spacek 2013-03-19 09:01:11 UTC

This bug is created as a clone of upstream ticket:
https://fedorahosted.org/bind-dyndb-ldap/ticket/110

* Define some global DNS option, e.g. `idnsAllowSyncPTR` attribute in global configuration object `cn=dns, dc=example, dc=com`.
* Start or reload BIND.
* Keep your fingers crossed, this problem not so often on RHEL 6.4.
* Check logs.

The error is more likely in latest builds from master (e1122fde894946d5cf4aa209df4c7060bb877d0a).

`/var/log/messages`:
{{{
13-Mar-2013 19:50:06.718 examining set of settings 'LDAP idnsConfig object for database ipa'
13-Mar-2013 19:50:06.718 setting 'dyn_update' was found in set 'LDAP idnsConfig object for database ipa'
13-Mar-2013 19:50:06.718 examining set of settings 'LDAP idnsConfig object for database ipa'
13-Mar-2013 19:50:06.718 setting 'dyn_update' was found in set 'LDAP idnsConfig object for database ipa'
13-Mar-2013 19:50:06.718 [settings.c     :  419: setting_update_from_ldap_entry] check failed: ignore
13-Mar-2013 19:50:06.718 zone 168.192.IN-ADDR.ARPA/IN: loaded; checking validity
13-Mar-2013 19:50:06.718 examining set of settings 'LDAP idnsConfig object for database ipa'
13-Mar-2013 19:50:06.718 setting 'sync_ptr' was found in set 'LDAP idnsConfig object for database ipa'
13-Mar-2013 19:50:06.718 examining set of settings 'LDAP idnsConfig object for database ipa'
13-Mar-2013 19:50:06.718 setting 'sync_ptr' was found in set 'LDAP idnsConfig object for database ipa'
13-Mar-2013 19:50:06.718 task.c:1678: REQUIRE(task->state == task_state_running) failed, back trace
13-Mar-2013 19:50:06.718 exiting (due to assertion failure)
}}}

Comment 1 Petr Spacek 2013-03-19 09:12:25 UTC

Workaround:
Remove all global configuration options from LDAP.

IPA command:
$ ipa dnsconfig-mod --forwarder='' --forward-policy='' --allow-sync-ptr='' --zone-refresh=''

Global forwarders and zone refresh parameters can be configured per-server in /etc/named.conf. Zone refresh was superseded by persistent search in IPA version 3.0 and higher and should not be enabled.

'Sync PTR' feature can be configured per server in /etc/named.conf and also per-zone in LDAP (via ipa dnszone-mod).

Comment 5 Petr Spacek 2013-03-20 15:47:04 UTC

BIND will crash if following conditions are met at the same time:
* Persistent search is enabled (default from IPA 3.0)
* Configuration of PTR synchronization feature has different value in global configuration and in local /etc/named.conf. I.e. PTR synchronization is globally enabled and locally disabled or vice versa.

Simpler workaround:
* Configure PTR synchronization in /etc/named.conf or per-zone as described in comment #1.
* Remove configuration for PTR synchronization from global configuration:
$ ipa dnsconfig-mod --allow-sync-ptr=''

OR

* Disable persistent search.

Comment 15 Petr Spacek 2013-04-15 14:45:28 UTC

This issue is fixed by http://rhn.redhat.com/errata/RHBA-2013-0739.html . Why is the status still MODIFIED?

Comment 16 Martin Kosek 2013-04-15 14:50:57 UTC

(In reply to comment #15)
> This issue is fixed by http://rhn.redhat.com/errata/RHBA-2013-0739.html .
> Why is the status still MODIFIED?

Because the bug was not added to the list of bugs fixed in an errata? If this is the case, we should close this bug&fill fixed in field.

Comment 17 Martin Kosek 2013-04-15 15:16:30 UTC

Ah, I see it now, this Bugzilla is for 6.5 - but I still think that Fixed In Version should be filled.

Comment 21 Namita Soman 2013-09-09 13:32:22 UTC

Tested using:
ipa-server-3.0.0-33.el6.x86_64
bind-dyndb-ldap-2.3-4.el6.x86_64

# ipa dnsconfig-mod --allow-sync-ptr=TRUE
  Allow PTR sync: TRUE

# service named restart
Stopping named: .[  OK  ]
Starting named: [  OK  ]

Not seeing the behaviour reported above.

From https://bugzilla.redhat.com/show_bug.cgi?id=928429#c10, verifying Sanity Only.

Comment 22 errata-xmlrpc 2013-11-21 12:11:05 UTC

Since the problem described in this bug report should be
resolved in a recent advisory, it has been closed with a
resolution of ERRATA.

For information on the advisory, and where to find the updated
files, follow the link below.

If the solution does not work for you, open a new bug report.

http://rhn.redhat.com/errata/RHBA-2013-1636.html