Internal Server Error 500 while accessing /admin/application_settings/general after upgrading to 13.12.8

Hi,

I hope someone had encountered such issues before. I got 500 while I have HTTP GET on the self-managed Gitlab at /admin/application_settings/general once I upgrade it to 13.12.8 from 13.7. I think this is probably something wrong in Gitlab config rather than a Gitlab issue as I don’t have issues on the other Gitlab instance that has the same version.

I have tried gitlab-ctl reconfigure or gitlab-rake cache:clear as someone suggested, but it didn’t fix the issue.

The error message I can find in the production_json.log is like below.

{
   "method":"GET",
   "path":"/admin/application_settings/general",
   "format":"html",
   "controller":"Admin::ApplicationSettingsController",
   "action":"general",
   "status":500,
   "time":"2021-07-20T23:45:50.606Z",
   "params":[
      
   ],
   "remote_ip":"150.111.211.111",
   "user_id":1111,
   "username":"test",
   "ua":"Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/91.0.4472.77 Safari/537.36",
   "correlation_id":"01FBG0Z06HQ5J353ZWDPH35DS3",
   "meta.user":"test",
   "meta.caller_id":"Admin::ApplicationSettingsController#general",
   "meta.remote_ip":"150.111.211.111",
   "meta.feature_category":"not_owned",
   "meta.client_id":"user/1111",
   "redis_calls":2,
   "redis_duration_s":0.0013319999999999999,
   "redis_read_bytes":529,
   "redis_write_bytes":810,
   "redis_cache_calls":1,
   "redis_cache_duration_s":0.000611,
   "redis_cache_read_bytes":198,
   "redis_cache_write_bytes":35,
   "redis_shared_state_calls":1,
   "redis_shared_state_duration_s":0.000721,
   "redis_shared_state_read_bytes":331,
   "redis_shared_state_write_bytes":775,
   "db_count":10,
   "db_write_count":0,
   "db_cached_count":4,
   "cpu_s":0.255624,
   "mem_objects":245130,
   "mem_bytes":21629539,
   "mem_mallocs":103268,
   "mem_total_bytes":31434739,
   "exception.class":"ActionView::Template::Error",
   "exception.message":"undefined method `accessor' for #<ActiveModel::Type::Value:0x00007ff30f36b0a0>",
   "exception.backtrace":[
      "app/views/admin/application_settings/_kroki.html.haml:30",
      "app/views/admin/application_settings/_kroki.html.haml:28:in `each'",
      "app/views/admin/application_settings/_kroki.html.haml:28",
      "app/views/admin/application_settings/_kroki.html.haml:11",
      "app/views/admin/application_settings/general.html.haml:108",
      "app/controllers/application_controller.rb:128:in `render'",
      "app/controllers/application_controller.rb:490:in `set_current_admin'",
      "lib/gitlab/session.rb:11:in `with_session'",
      "app/controllers/application_controller.rb:481:in `set_session_storage'",
      "lib/gitlab/i18n.rb:99:in `with_locale'",
      "lib/gitlab/i18n.rb:105:in `with_user_locale'",
      "app/controllers/application_controller.rb:475:in `set_locale'",
      "app/controllers/application_controller.rb:468:in `block in set_current_context'",
      "lib/gitlab/application_context.rb:70:in `block in use'",
      "lib/gitlab/application_context.rb:70:in `use'",
      "lib/gitlab/application_context.rb:27:in `with_context'",
      "app/controllers/application_controller.rb:459:in `set_current_context'",
      "lib/gitlab/middleware/speedscope.rb:13:in `call'",
      "lib/gitlab/request_profiler/middleware.rb:17:in `call'",
      "lib/gitlab/jira/middleware.rb:19:in `call'",
      "lib/gitlab/middleware/go.rb:20:in `call'",
      "lib/gitlab/etag_caching/middleware.rb:21:in `call'",
      "lib/gitlab/middleware/multipart.rb:172:in `call'",
      "lib/gitlab/middleware/read_only/controller.rb:50:in `call'",
      "lib/gitlab/middleware/read_only.rb:18:in `call'",
      "lib/gitlab/middleware/same_site_cookies.rb:27:in `call'",
      "lib/gitlab/middleware/handle_malformed_strings.rb:21:in `call'",
      "lib/gitlab/middleware/basic_health_check.rb:25:in `call'",
      "lib/gitlab/middleware/handle_ip_spoof_attack_error.rb:25:in `call'",
      "lib/gitlab/middleware/request_context.rb:21:in `call'",
      "config/initializers/fix_local_cache_middleware.rb:11:in `call'",
      "lib/gitlab/middleware/rack_multipart_tempfile_factory.rb:19:in `call'",
      "lib/gitlab/metrics/requests_rack_middleware.rb:76:in `call'",
      "lib/gitlab/middleware/release_env.rb:12:in `call'"
   ],
   "db_duration_s":0.01678,
   "view_duration_s":0.0,
   "duration_s":0.29621
}

okay, I fixed this by reinstall gitlab-ce package. All good.