Merge branch 'security-todos-redact-guests' into 'master'

Security: Redact confidential todos when membership changed to guest

See merge request gitlab-org/security/gitlab!900

app/services/members/base_service.rb

@@ -7,6 +7,11 @@ module Members
     def initialize(current_user = nil, params = {})
       @current_user = current_user
       @params = params
+
+      # could be a string, force to an integer, part of fix
+      # https://gitlab.com/gitlab-org/gitlab/-/issues/219496
+      # Allow the ArgumentError to be raised if it can't be converted to an integer.
+      @params[:access_level] = Integer(@params[:access_level]) if @params[:access_level]
     end
 
     def after_execute(args)

app/services/todos/destroy/entity_leave_service.rb

@@ -52,7 +52,14 @@ module Todos
 
       # rubocop: disable CodeReuse/ActiveRecord
       def remove_project_todos
-        Todo.where(project_id: non_authorized_projects, user_id: user.id).delete_all
+        # Issues are viewable by guests (even in private projects), so remove those todos
+        # from projects without guest access
+        Todo.where(project_id: non_authorized_guest_projects, user_id: user.id)
+          .delete_all
+
+        # MRs require reporter access, so remove those todos that are not authorized
+        Todo.where(project_id: non_authorized_reporter_projects, target_type: MergeRequest.name, user_id: user.id)
+          .delete_all
       end
       # rubocop: enable CodeReuse/ActiveRecord
 
@@ -68,7 +75,7 @@ module Todos
                     when Project
                       { id: entity.id }
                     when Namespace
-                      { namespace_id: non_member_groups }
+                      { namespace_id: non_authorized_reporter_groups }
                     end
 
         Project.where(condition)
@@ -76,8 +83,32 @@ module Todos
       # rubocop: enable CodeReuse/ActiveRecord
 
       # rubocop: disable CodeReuse/ActiveRecord
-      def non_authorized_projects
-        projects.where('id NOT IN (?)', user.authorized_projects.select(:id))
+      def authorized_reporter_projects
+        user.authorized_projects(Gitlab::Access::REPORTER).select(:id)
+      end
+      # rubocop: enable CodeReuse/ActiveRecord
+
+      # rubocop: disable CodeReuse/ActiveRecord
+      def authorized_guest_projects
+        user.authorized_projects(Gitlab::Access::GUEST).select(:id)
+      end
+      # rubocop: enable CodeReuse/ActiveRecord
+
+      # rubocop: disable CodeReuse/ActiveRecord
+      def non_authorized_reporter_projects
+        projects.where('id NOT IN (?)', authorized_reporter_projects)
+      end
+      # rubocop: enable CodeReuse/ActiveRecord
+
+      # rubocop: disable CodeReuse/ActiveRecord
+      def non_authorized_guest_projects
+        projects.where('id NOT IN (?)', authorized_guest_projects)
+      end
+      # rubocop: enable CodeReuse/ActiveRecord
+
+      # rubocop: disable CodeReuse/ActiveRecord
+      def authorized_reporter_groups
+        GroupsFinder.new(user, min_access_level: Gitlab::Access::REPORTER).execute.select(:id)
       end
       # rubocop: enable CodeReuse/ActiveRecord
 
@@ -91,9 +122,9 @@ module Todos
       # rubocop: enable CodeReuse/ActiveRecord
 
       # rubocop: disable CodeReuse/ActiveRecord
-      def non_member_groups
+      def non_authorized_reporter_groups
         entity.self_and_descendants.select(:id)
-          .where('id NOT IN (?)', user.membership_groups.select(:id))
+          .where('id NOT IN (?)', authorized_reporter_groups)
       end
       # rubocop: enable CodeReuse/ActiveRecord
 
@@ -106,8 +137,6 @@ module Todos
       # rubocop: disable CodeReuse/ActiveRecord
       def confidential_issues
         assigned_ids = IssueAssignee.select(:issue_id).where(user_id: user.id)
-        authorized_reporter_projects = user
-          .authorized_projects(Gitlab::Access::REPORTER).select(:id)
 
         Issue.where(project_id: projects, confidential: true)
           .where('project_id NOT IN(?)', authorized_reporter_projects)

changelogs/unreleased/security-todos-redact-guests.yml

+---
+title: Fix redaction of confidential Todos
+merge_request:
+author:
+type: security

spec/services/members/update_service_spec.rb

@@ -31,17 +31,35 @@ RSpec.describe Members::UpdateService do
     end
 
     context 'when member is downgraded to guest' do
-      let(:params) do
-        { access_level: Gitlab::Access::GUEST }
+      shared_examples 'schedules to delete confidential todos' do
+        it do
+          expect(TodosDestroyer::EntityLeaveWorker).to receive(:perform_in).with(Todo::WAIT_FOR_DELETE, member.user_id, member.source_id, source.class.name).once
+
+          updated_member = described_class.new(current_user, params).execute(member, permission: permission)
+
+          expect(updated_member).to be_valid
+          expect(updated_member.access_level).to eq(Gitlab::Access::GUEST)
+        end
+      end
+
+      context 'with Gitlab::Access::GUEST level as a string' do
+        let(:params) { { access_level: Gitlab::Access::GUEST.to_s } }
+
+        it_behaves_like 'schedules to delete confidential todos'
       end
 
-      it 'schedules to delete confidential todos' do
-        expect(TodosDestroyer::EntityLeaveWorker).to receive(:perform_in).with(Todo::WAIT_FOR_DELETE, member.user_id, member.source_id, source.class.name).once
+      context 'with Gitlab::Access::GUEST level as an integer' do
+        let(:params) { { access_level: Gitlab::Access::GUEST } }
+
+        it_behaves_like 'schedules to delete confidential todos'
+      end
+    end
 
-        updated_member = described_class.new(current_user, params).execute(member, permission: permission)
+    context 'when access_level is invalid' do
+      let(:params) { { access_level: 'invalid' } }
 
-        expect(updated_member).to be_valid
-        expect(updated_member.access_level).to eq(Gitlab::Access::GUEST)
+      it 'raises an error' do
+        expect { described_class.new(current_user, params) }.to raise_error(ArgumentError, 'invalid value for Integer(): "invalid"')
       end
     end
   end