Merge branch 'security-12630-private-system-note-disclosed-in-graphql-12-3-ce' into '12-3-stable'

Add policy check if cross reference system notes are accessible

See merge request gitlab/gitlabhq!3426

2 files changed, 10 insertions, 0 deletions

diff --git a/app/models/discussion.rb b/app/models/discussion.rb
index dd896f77084..0d066d0d99f 100644
--- a/app/models/discussion.rb
+++ b/app/models/discussion.rb
@@ -18,6 +18,7 @@ class Discussion
             :for_merge_request?,
             :to_ability_name,
             :editable?,
+            :visible_for?,
 
             to: :first_note
 
diff --git a/app/policies/note_policy.rb b/app/policies/note_policy.rb
index 8d23e3abed3..b2af6c874c7 100644
--- a/app/policies/note_policy.rb
+++ b/app/policies/note_policy.rb
@@ -11,6 +11,8 @@ class NotePolicy < BasePolicy
 
   condition(:can_read_noteable) { can?(:"read_#{@subject.to_ability_name}") }
 
+  condition(:is_visible) { @subject.visible_for?(@user) }
+
   rule { ~editable }.prevent :admin_note
 
   # If user can't read the issue/MR/etc then they should not be allowed to do anything to their own notes
@@ -27,6 +29,13 @@ class NotePolicy < BasePolicy
     enable :resolve_note
   end
 
+  rule { ~is_visible }.policy do
+    prevent :read_note
+    prevent :admin_note
+    prevent :resolve_note
+    prevent :award_emoji
+  end
+
   rule { is_noteable_author }.policy do
     enable :resolve_note
   end