First connexion of LDAP user throw exception

[agrimal]

Hello,

I'm on a fresh install of NextCLoud on Ubuntu 18.04.1, installed from source.
Nextcloud 14.0.1
http server : apache2 2.4.29-1ubuntu4.3
php : 7.2.10-0ubuntu0.18.04.1
reverse proxy : nginx 1.14.0-0ubuntu1.1
database : mariadb 10.1.34-MariaDB-0ubuntu0.18.04.1

I configured authentication against my OpenLDAP server and everything works fine except one thing : when a user log in for the first time, he is getting an error like "internal server error" on his web client. After that, he just needs to refresh the page and the user is automatically logged in, and no problem after that.

On the server side, i get a big one-line red log :

2018-10-01T01:14:24+0200 nextcloud01 Nextcloud[11297]: {index} {"Exception":"Error","Message":"Call to a member function getBackendClassName() on null","Code":0,"Trace":[{"file":"\/srv\/nextcloud_archives\/nextcloud-14.0.1\/nextcloud\/apps\/dav\/lib\/HookManager.php","line":104,"function":"updateUser","class":"OCA\\DAV\\CardDAV\\SyncService","type":"->","args":["*** sensitive parameter replaced ***"]},{"file":"\/srv\/nextcloud_archives\/nextcloud-14.0.1\/nextcloud\/apps\/dav\/lib\/HookManager.php","line":81,"function":"postCreateUser","class":"OCA\\DAV\\HookManager","type":"->","args":[{"uid":"*** sensitive parameter replaced ***"}]},{"function":"OCA\\DAV\\{closure}","class":"OCA\\DAV\\HookManager","type":"->","args":["*** sensitive parameters replaced ***"]},{"file":"\/srv\/nextcloud_archives\/nextcloud-14.0.1\/nextcloud\/lib\/private\/Hooks\/EmitterTrait.php","line":99,"function":"call_user_func_array","args":[{"__class__":"Closure"},["*** sensitive parameter replaced ***"]]},{"file":"\/srv\/nextcloud_archives\/nextcloud-14.0.1\/nextcloud\/lib\/private\/Hooks\/PublicEmitter.php","line":36,"function":"emit","class":"OC\\Hooks\\BasicEmitter","type":"->","args":["\\OC\\User","assignedUserId",["*** sensitive parameter replaced ***"]]},{"file":"\/srv\/nextcloud_archives\/nextcloud-14.0.1\/nextcloud\/apps\/user_ldap\/lib\/Access.php","line":618,"function":"emit","class":"OC\\Hooks\\PublicEmitter","type":"->","args":["\\OC\\User","assignedUserId",["*** sensitive parameter replaced ***"]]},{"file":"\/srv\/nextcloud_archives\/nextcloud-14.0.1\/nextcloud\/apps\/user_ldap\/lib\/Access.php","line":875,"function":"dn2ocname","class":"OCA\\User_LDAP\\Access","type":"->","args":["uid=test.user,ou=users,dc=example,dc=fr","Test User","*** sensitive parameter replaced ***",false,"*** sensitive parameter replaced ***"]},{"function":"OCA\\User_LDAP\\{closure}","class":"OCA\\User_LDAP\\Access","type":"->","args":["*** sensitive parameters replaced ***"]},{"file":"\/srv\/nextcloud_archives\/nextcloud-14.0.1\/nextcloud\/apps\/user_ldap\/lib\/Access.php","line":880,"function":"array_filter","args":[["*** sensitive parameter replaced ***"],{"__class__":"Closure"}]},{"file":"\/srv\/nextcloud_archives\/nextcloud-14.0.1\/nextcloud\/apps\/user_ldap\/lib\/Access.php","line":843,"function":"fetchListOfUsers","class":"OCA\\User_LDAP\\Access","type":"->","args":["(&(objectclass=inetOrgPerson)(uid=test.user))",["entryuuid","nsuniqueid","objectguid","guid","ipauniqueid","dn","uid","samaccountname","memberof","uid","","mail","cn","","jpegphoto","thumbnailphoto"]]},{"file":"\/srv\/nextcloud_archives\/nextcloud-14.0.1\/nextcloud\/apps\/user_ldap\/lib\/User_LDAP.php","line":172,"function":"fetchUsersByLoginName","class":"OCA\\User_LDAP\\Access","type":"->","args":["*** sensitive parameter replaced ***",["entryuuid","nsuniqueid","objectguid","guid","ipauniqueid","dn","uid","samaccountname","memberof","uid","","mail","cn","","jpegphoto","thumbnailphoto"]]},{"file":"\/srv\/nextcloud_archives\/nextcloud-14.0.1\/nextcloud\/apps\/user_ldap\/lib\/User_LDAP.php","line":189,"function":"getLDAPUserByLoginName","class":"OCA\\User_LDAP\\User_LDAP","type":"->","args":["*** sensitive parameter replaced ***"]},{"function":"checkPassword","class":"OCA\\User_LDAP\\User_LDAP","type":"->","args":["*** sensitive parameters replaced ***"]},{"file":"\/srv\/nextcloud_archives\/nextcloud-14.0.1\/nextcloud\/apps\/user_ldap\/lib\/User_Proxy.php","line":81,"function":"call_user_func_array","args":[[{"__class__":"OCA\\User_LDAP\\User_LDAP"},"checkPassword"],["*** sensitive parameter replaced ***","*** sensitive parameter replaced ***"]]},{"file":"\/srv\/nextcloud_archives\/nextcloud-14.0.1\/nextcloud\/apps\/user_ldap\/lib\/Proxy.php","line":152,"function":"walkBackends","class":"OCA\\User_LDAP\\User_Proxy","type":"->","args":["*** sensitive parameter replaced ***","checkPassword",["*** sensitive parameter replaced ***","*** sensitive parameter replaced ***"]]},{"file":"\/srv\/nextcloud_archives\/nextcloud-14.0.1\/nextcloud\/apps\/user_ldap\/lib\/User_Proxy.php","line":196,"function":"handleRequest","class":"OCA\\User_LDAP\\Proxy","type":"->","args":["*** sensitive parameter replaced ***","checkPassword",["*** sensitive parameter replaced ***","*** sensitive parameter replaced ***"]]},{"file":"\/srv\/nextcloud_archives\/nextcloud-14.0.1\/nextcloud\/lib\/private\/User\/Manager.php","line":208,"function":"checkPassword","class":"OCA\\User_LDAP\\User_Proxy","type":"->","args":["*** sensitive parameters replaced ***"]},{"file":"\/srv\/nextcloud_archives\/nextcloud-14.0.1\/nextcloud\/core\/Controller\/LoginController.php","line":298,"function":"checkPasswordNoLogging","class":"OC\\User\\Manager","type":"->","args":["*** sensitive parameters replaced ***"]},{"file":"\/srv\/nextcloud_archives\/nextcloud-14.0.1\/nextcloud\/lib\/private\/AppFramework\/Http\/Dispatcher.php","line":166,"function":"tryLogin","class":"OC\\Core\\Controller\\LoginController","type":"->","args":["*** sensitive parameters replaced ***"]},{"file":"\/srv\/nextcloud_archives\/nextcloud-14.0.1\/nextcloud\/lib\/private\/AppFramework\/Http\/Dispatcher.php","line":99,"function":"executeController","class":"OC\\AppFramework\\Http\\Dispatcher","type":"->","args":[{"__class__":"OC\\Core\\Controller\\LoginController"},"tryLogin"]},{"file":"\/srv\/nextcloud_archives\/nextcloud-14.0.1\/nextcloud\/lib\/private\/AppFramework\/App.php","line":118,"function":"dispatch","class":"OC\\AppFramework\\Http\\Dispatcher","type":"->","args":[{"__class__":"OC\\Core\\Controller\\LoginController"},"tryLogin"]},{"file":"\/srv\/nextcloud_archives\/nextcloud-14.0.1\/nextcloud\/lib\/private\/AppFramework\/Routing\/RouteActionHandler.php","line":47,"function":"main","class":"OC\\AppFramework\\App","type":"::","args":["OC\\Core\\Controller\\LoginController","tryLogin",{"__class__":"OC\\AppFramework\\DependencyInjection\\DIContainer"},{"_route":"core.login.tryLogin"}]},{"function":"__invoke","class":"OC\\AppFramework\\Routing\\RouteActionHandler","type":"->","args":[{"_route":"core.login.tryLogin"}]},{"file":"\/srv\/nextcloud_archives\/nextcloud-14.0.1\/nextcloud\/lib\/private\/Route\/Router.php","line":297,"function":"call_user_func","args":[{"__class__":"OC\\AppFramework\\Routing\\RouteActionHandler"},{"_route":"core.login.tryLogin"}]},{"file":"\/srv\/nextcloud_archives\/nextcloud-14.0.1\/nextcloud\/lib\/base.php","line":987,"function":"match","class":"OC\\Route\\Router","type":"->","args":["\/login"]},{"file":"\/srv\/nextcloud_archives\/nextcloud-14.0.1\/nextcloud\/index.php","line":42,"function":"handleRequest","class":"OC","type":"::","args":[]}],"File":"\/srv\/nextcloud_archives\/nextcloud-14.0.1\/nextcloud\/apps\/dav\/lib\/CardDAV\/SyncService.php","Line":268,"CustomMessage":"--"}

Every time i create another user, i get the same error on first login.

Here is my config :

# sudo -u www-data php occ app:list
Enabled:
  - accessibility: 1.0.1
  - activity: 2.7.0
  - admin_audit: 1.4.0
  - bruteforcesettings: 1.1.0
  - cloud_federation_api: 0.0.1
  - comments: 1.4.0
  - dav: 1.6.0
  - federatedfilesharing: 1.4.0
  - federation: 1.4.0
  - files: 1.9.0
  - files_pdfviewer: 1.3.2
  - files_sharing: 1.6.2
  - files_texteditor: 2.6.0
  - files_trashbin: 1.4.1
  - files_versions: 1.7.1
  - files_videoplayer: 1.3.0
  - firstrunwizard: 2.3.0
  - gallery: 18.1.0
  - logreader: 2.0.0
  - lookup_server_connector: 1.2.0
  - nextcloud_announcements: 1.3.0
  - notifications: 2.2.1
  - oauth2: 1.2.1
  - password_policy: 1.4.0
  - provisioning_api: 1.4.0
  - quota_warning: 1.3.0
  - serverinfo: 1.4.0
  - sharebymail: 1.4.0
  - support: 1.0.0
  - survey_client: 1.2.0
  - systemtags: 1.4.0
  - theming: 1.5.0
  - twofactor_backupcodes: 1.3.1
  - updatenotification: 1.4.1
  - user_ldap: 1.4.0
  - workflowengine: 1.4.0
Disabled:
  - encryption
  - files_external
  - user_external

MariaDB [nextcloud]> SELECT * FROM oc_appconfig WHERE appid LIKE 'user_ldap';
+-----------+--------------------------------------+----------------------------------------------------------------------+
| appid     | configkey                            | configvalue                                                          |
+-----------+--------------------------------------+----------------------------------------------------------------------+
| user_ldap | background_sync_interval             | 43200                                                                |
| user_ldap | background_sync_offset               | 0                                                                    |
| user_ldap | background_sync_prefix               | s01                                                                  |
| user_ldap | cleanUpJobOffset                     | 0                                                                    |
| user_ldap | enabled                              | yes                                                                  |
| user_ldap | installed_version                    | 1.4.0                                                                |
| user_ldap | s01_lastChange                       | 1538348607                                                           |
| user_ldap | s01has_memberof_filter_support       |                                                                      |
| user_ldap | s01home_folder_naming_rule           |                                                                      |
| user_ldap | s01last_jpegPhoto_lookup             | 0                                                                    |
| user_ldap | s01ldap_agent_password               | UnFiMDRKTkd4a0RxNzQxU0hySE1yYzZrRkI1RjVVWmF4TzM0ek10SlU1njU4VUticpU= |
| user_ldap | s01ldap_attributes_for_group_search  |                                                                      |
| user_ldap | s01ldap_attributes_for_user_search   |                                                                      |
| user_ldap | s01ldap_backup_host                  |                                                                      |
| user_ldap | s01ldap_backup_port                  |                                                                      |
| user_ldap | s01ldap_base                         | dc=example,dc=fr                                                     |
| user_ldap | s01ldap_base_groups                  | ou=groups,dc=example,dc=fr                                           |
| user_ldap | s01ldap_base_users                   | ou=users,dc=example,dc=fr                                            |
| user_ldap | s01ldap_cache_ttl                    | 600                                                                  |
| user_ldap | s01ldap_configuration_active         | 1                                                                    |
| user_ldap | s01ldap_default_ppolicy_dn           |                                                                      |
| user_ldap | s01ldap_display_name                 | cn                                                                   |
| user_ldap | s01ldap_dn                           | uid=nextcloud,ou=applications,dc=example,dc=fr                       |
| user_ldap | s01ldap_dynamic_group_member_url     |                                                                      |
| user_ldap | s01ldap_email_attr                   | mail                                                                 |
| user_ldap | s01ldap_experienced_admin            | 0                                                                    |
| user_ldap | s01ldap_expert_username_attr         |                                                                      |
| user_ldap | s01ldap_expert_uuid_group_attr       | uid                                                                  |
| user_ldap | s01ldap_expert_uuid_user_attr        | uid                                                                  |
| user_ldap | s01ldap_gid_number                   | gidNumber                                                            |
| user_ldap | s01ldap_group_display_name           | cn                                                                   |
| user_ldap | s01ldap_group_filter                 |                                                                      |
| user_ldap | s01ldap_group_filter_mode            | 0                                                                    |
| user_ldap | s01ldap_group_member_assoc_attribute | gidNumber                                                            |
| user_ldap | s01ldap_groupfilter_groups           |                                                                      |
| user_ldap | s01ldap_groupfilter_objectclass      |                                                                      |
| user_ldap | s01ldap_host                         | ldaps://ldap.example.fr                                              |
| user_ldap | s01ldap_login_filter                 | (&(objectclass=inetOrgPerson)(uid=%uid))                             |
| user_ldap | s01ldap_login_filter_mode            | 1                                                                    |
| user_ldap | s01ldap_loginfilter_attributes       | uid                                                                  |
| user_ldap | s01ldap_loginfilter_email            | 0                                                                    |
| user_ldap | s01ldap_loginfilter_username         | 0                                                                    |
| user_ldap | s01ldap_nested_groups                | 0                                                                    |
| user_ldap | s01ldap_override_main_server         |                                                                      |
| user_ldap | s01ldap_paging_size                  | 500                                                                  |
| user_ldap | s01ldap_port                         | 636                                                                  |
| user_ldap | s01ldap_quota_attr                   |                                                                      |
| user_ldap | s01ldap_quota_def                    |                                                                      |
| user_ldap | s01ldap_tls                          | 0                                                                    |
| user_ldap | s01ldap_turn_off_cert_check          | 0                                                                    |
| user_ldap | s01ldap_turn_on_pwd_change           | 1                                                                    |
| user_ldap | s01ldap_user_avatar_rule             | default                                                              |
| user_ldap | s01ldap_user_display_name_2          |                                                                      |
| user_ldap | s01ldap_user_filter_mode             | 1                                                                    |
| user_ldap | s01ldap_userfilter_groups            |                                                                      |
| user_ldap | s01ldap_userfilter_objectclass       | inetOrgPerson                                                        |
| user_ldap | s01ldap_userlist_filter              | (objectclass=inetOrgPerson)                                          |
| user_ldap | s01use_memberof_to_detect_membership | 1                                                                    |
| user_ldap | types                                | authentication                                                       |
+-----------+--------------------------------------+----------------------------------------------------------------------+

https://cloud.example.fr/index.php/settings/integrity/failed
No errors have been found.

# cat config/config.php
<?php
$CONFIG = array (
  'instanceid' => 'xxxxxxxxxxx',
  'passwordsalt' => 'xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx',
  'secret' => 'xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx',
  'trusted_domains' =>
  array (
    0 => 'cloud.example.fr',
    1 => 'other.example.fr',
  ),
  'datadirectory' => '/srv/nextcloud/data',
  'dbtype' => 'mysql',
  'version' => '14.0.1.1',
  'overwrite.cli.url' => 'https://cloud.example.fr',
  'overwriteprotocol' => 'https',
  'trusted_proxies' =>
  array (
    0 => '1.2.3.4',
  ),
  'dbname' => 'nextcloud',
  'dbhost' => 'mysql.example.fr',
  'dbport' => '',
  'dbtableprefix' => 'oc_',
  'dbuser' => 'nextcloud',
  'dbpassword' => 'xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx',
  'installed' => true,
  'ldapIgnoreNamingRules' => false,
  'ldapProviderFactory' => 'OCA\\User_LDAP\\LDAPProviderFactory',
  'mail_from_address' => 'admin',
  'mail_smtpmode' => 'smtp',
  'mail_smtpauthtype' => 'PLAIN',
  'mail_domain' => 'example.fr',
  'mail_smtphost' => '127.0.0.1',
  'mail_smtpport' => '25',
  'updater.release.channel' => 'production',
  'memcache.local' => '\OC\Memcache\APCu',
  'redis' => array(
    'host' => 'localhost',
    'port' => 6379,
  ),
  'memcache.locking' => '\OC\Memcache\Redis',
  'log_type' => 'syslog',
  'loglevel' => 1,
);

[nextcloud-bot]

GitMate.io thinks possibly related issues are #10954 (OCC upgrade throws unhandled exception), #4882 (Impersonating new LDAP user fails), #8852 (LDAP ignores user filter, causing exceptions), #11213 (LDAP Users Problem. Several Other Problems), and #1470 (Avoid warning for non-existing LDAP users).

[agrimal]

I found that this bug appears when I set :

• ldapExpertUsernameAttr to "uid" without modifying ldapExpertUUIDUserAttr or
• ldapExpertUUIDUserAttr to "uid" without modifying ldapExpertUsernameAttr

When I set ldapExpertUsernameAttr to "cn" and ldapExpertUUIDUserAttr to "uid", everything works fine.

[gramakri]

We hit this exact issue with NC 14.0.x on Cloudron as well. The first LDAP login fails with the same backtrace as above but subsequent logins work.

[gramakri]

https://paste.cloudron.io/elijoyeqop.http has the stack trace.

[blizzz]

proposed fix in #12693, thanks for reporting!