Upgrade failure caused by ldap configuration error during 'apt update'

During an upgrade from 11.10 to 12.1, I experienced an error. From what I can work out, the ldap configuration got overwritten and after correcting it, I no longer have proper access to the xwiki content

More details

So, ldap is authenticating again. Somehow, during the upgrade process, the xwiki.authentication.ldap.bind_DN line in xwiki.cfg got overwritten.

Now the problem is… well, I don’t know what the problem is.

As superadmin, I cannot access anything important. As an admin user (my own, via ldap), I just get a mess.

when trying to access the administration section as superadmin

when trying to access the administration section as me, an admin level user via ldap

Is there any possibility I can recover from this mess? Do I need to reinstall xwiki and then restore the database?

What is the use of the superadmin account, if it cannot bypass the permissions when needed?

Normally I’d have a full backup before attempting an update, but this time I thoughtlessly did an “apt update” forgetting to check if xwiki was on the update list.

Any advice for recovering from this self inflicted mess would be greatly appreciated.

One last thing that may or may not be relevant; the following errors are new:

1/ WARN ltInstalledExtensionRepository - Invalid extension [asm:asm/20041228.180559] on namespace [wiki:xwiki] (InvalidExtensionException: Extension [asm:asm/20041228.180559] already exists as a core extension)

2/ ERROR .i.XWikiCfgConfigurationSource - Failed to load configuration, java.lang.IllegalArgumentException: Malformed \uxxxx encoding.

(from catalina.out)

I added to the logback.xml file, but I didn’t get any additional information.

INFO: Starting Servlet Engine: Apache Tomcat/8.0.32 (Ubuntu)
Mar 16, 2020 11:09:01 AM org.apache.catalina.startup.HostConfig deployDescriptor
INFO: Deploying configuration descriptor /etc/tomcat8/Catalina/localhost/xwiki.xml
2020-03-16 11:09:17,775 [localhost-startStop-1] INFO iPropertiesConfigurationSource - loading xwiki.properties from default location /etc/xwiki/xwiki.properties
2020-03-16 11:09:18,379 [localhost-startStop-1] INFO o.x.e.i.ServletEnvironment - Using permanent directory [/var/lib/xwiki/data]
2020-03-16 11:09:29,331 [localhost-startStop-1] WARN ltInstalledExtensionRepository - Invalid extension [asm:asm/20041228.180559] on namespace [wiki:xwiki] (InvalidExtensionException: Extension [asm:asm/20041228.180559] already exists as a core extension)
2020-03-16 11:09:39,158 [localhost-startStop-1] ERROR .i.XWikiCfgConfigurationSource - Failed to load configuration
java.lang.IllegalArgumentException: Malformed \uxxxx encoding.
at java.util.Properties.loadConvert(Properties.java:574)
at java.util.Properties.load0(Properties.java:391)
at java.util.Properties.load(Properties.java:341)
at com.xpn.xwiki.internal.XWikiCfgConfigurationSource.initialize(XWikiCfgConfigurationSource.java:108)

As far as I can tell, xwiki.cfg is a plain ascii file, as is every other configuration file in the /etc/xwiki/ directory

root@wiki:/etc/xwiki# file *
cache:                          directory
classes:                        directory
extensions:                     directory
fonts:                          directory
hibernate.cfg.xml:              XML 1.0 document, ASCII text
jboss-deployment-structure.xml: XML 1.0 document, ASCII text
jetty-web.xml:                  XML 1.0 document, ASCII text
logback.xml:                    XML 1.0 document, ASCII text
observation:                    directory
portlet.xml:                    XML 1.0 document, ASCII text
struts-config.xml:              XML 1.0 document, ASCII text
sun-web.xml:                    XML 1.0 document, ASCII text
version.properties:             ASCII text
web.xml:                        XML 1.0 document, ASCII text
xwiki.cfg:                      ASCII text
xwiki-locales.txt:              ASCII text
xwiki.properties:               ASCII text, with very long lines
xwiki-tomcat8.xml:              XML 1.0 document, ASCII text

Here is an error that appears when logged in as the previous ldap admin user

2020-03-16 11:14:44,622 [XWiki initialization] ERROR cumentTranslationBundleFactory - Failed to register translation bundle from document [xwiki:Menu.MenuTranslations]
org.xwiki.security.authorization.AccessDeniedException: Access denied when checking [programming] access to [Main Wiki] for user [xwiki:XWiki.pdwalker]
at org.xwiki.security.authorization.DefaultAuthorizationManager.checkAccess(DefaultAuthorizationManager.java:94)