Unable to log in with 2FA

Summary

LDAP user tries to log in with 2FA.

Relevant logs and/or screenshots

production.log:

Started POST "/users/sign_in" for 78.34.55.172 at 2017-10-06 12:33:54 +0000
Processing by SessionsController#create as HTML
  Parameters: {"utf8"=>"✓", "authenticity_token"=>"[FILTERED]", "user"=>{"remember_me"=>"0", "otp_attempt"
=>"[FILTERED]"}}
Completed 500 Internal Server Error in 26ms (ActiveRecord: 0.3ms | Elasticsearch: 0.0ms)
Sending event e3df20744e66429d80e2ff9dca431d5f to Sentry
Started POST "/api/v4/jobs/request" for 52.30.107.173 at 2017-10-06 12:33:54 +0000
Started POST "/api/v4/jobs/request" for 52.30.107.173 at 2017-10-06 12:33:55 +0000

ActionView::Template::Error (undefined method `each_with_index' for nil:NilClass):
     5:   - if kerberos_enabled?
     6:     %li{ class: (:active unless crowd_enabled? || ldap_enabled?) }
     7:       = link_to "Kerberos", "#kerberos", 'data-toggle' => 'tab'
     8:   - @ldap_servers.each_with_index do |server, i|
     9:     %li{ class: active_when(i.zero? && !crowd_enabled?) }
    10:       = link_to server['label'], "##{server['provider_name']}",  'data-toggle' => 'tab'
    11:   - if password_authentication_enabled?
  app/views/devise/shared/_tabs_ldap.html.haml:8:in `_app_views_devise_shared__tabs_ldap_html_haml__369058
7594654192930_69991976666500'
  app/views/devise/sessions/new.html.haml:5:in `_app_views_devise_sessions_new_html_haml__3445175636319135
277_69991975340920'
  app/controllers/concerns/authenticates_with_two_factor.rb:35:in `locked_user_redirect'
  app/controllers/concerns/authenticates_with_two_factor.rb:40:in `authenticate_with_two_factor'
  lib/gitlab/middleware/multipart.rb:93:in `call'
  lib/gitlab/request_profiler/middleware.rb:14:in `call'
  lib/gitlab/jira/middleware.rb:15:in `call'
  lib/gitlab/middleware/go.rb:17:in `call'
  lib/gitlab/etag_caching/middleware.rb:11:in `call'
  lib/gitlab/middleware/readonly_geo.rb:30:in `call'
  lib/gitlab/request_context.rb:18:in `call'
  lib/gitlab/metrics/requests_rack_middleware.rb:27:in `call'

User sees message:

Could not authenticate you from Ldapmain because "Undefined method 'each with index' for nil:nilclass".

Results of GitLab environment info

Expand for output related to GitLab environment info

System information
System:         Debian 8.9
Proxy:          no
Current User:   git
Using RVM:      no
Ruby Version:   2.3.5p376
Gem Version:    2.6.13
Bundler Version:1.13.7
Rake Version:   12.0.0
Redis Version:  3.2.5
Git Version:    2.13.5
Sidekiq Version:5.0.4
Go Version:     unknown
GitLab information
Version:        10.0.2-ee
Revision:       f5b3271
Directory:      /opt/gitlab/embedded/service/gitlab-rails
DB Adapter:     postgresql
DB Version:     9.6.3
Elasticsearch:  yes
Geo:            no
Using LDAP:     yes
Using Omniauth: no
GitLab Shell
Version:        5.9.0
Repository storage paths:

• default: /var/opt/gitlab/git-data/repositories Hooks: /opt/gitlab/embedded/service/gitlab-shell/hooks Git: /opt/gitlab/embedded/bin/git