Cancel all running CI jobs when user is blocked

This prevents a MITM attack where attacker could
still access Git repository if any jobs were
running long enough.

2 files changed, 23 insertions, 0 deletions

diff --git a/app/models/user.rb b/app/models/user.rb
index 909f5f3873d..9aad9b5f51e 100644
--- a/app/models/user.rb
+++ b/app/models/user.rb
@@ -265,6 +265,16 @@ class User < ApplicationRecord
         BLOCKED_MESSAGE
       end
     end
+
+    # rubocop: disable CodeReuse/ServiceClass
+    # Ideally we should not call a service object here but user.block
+    # is also bcalled by Users::MigrateToGhostUserService which references
+    # this state transition object in order to do a rollback.
+    # For this reason the tradeoff is to disable this cop.
+    after_transition any => :blocked do |user|
+      Ci::CancelUserPipelinesService.new.execute(user)
+    end
+    # rubocop: enable CodeReuse/ServiceClass
   end
 
   # Scopes
diff --git a/app/services/ci/cancel_user_pipelines_service.rb b/app/services/ci/cancel_user_pipelines_service.rb
new file mode 100644
index 00000000000..bcafb6b4a35
--- /dev/null
+++ b/app/services/ci/cancel_user_pipelines_service.rb
@@ -0,0 +1,13 @@
+# frozen_string_literal: true
+
+module Ci
+  class CancelUserPipelinesService
+    # rubocop: disable CodeReuse/ActiveRecord
+    # This is a bug with CodeReuse/ActiveRecord cop
+    # https://gitlab.com/gitlab-org/gitlab/issues/32332
+    def execute(user)
+      user.pipelines.cancelable.find_each(&:cancel_running)
+    end
+    # rubocop: enable CodeReuse/ActiveRecord
+  end
+end