Add missing lock to rb_gc_impl_copy_finalizer

Author: byroot

gc/default/default.c

@@ -2803,6 +2803,7 @@ rb_gc_impl_copy_finalizer(void *objspace_ptr, VALUE dest, VALUE obj)
 
     if (!FL_TEST(obj, FL_FINALIZE)) return;
 
+    int lev = rb_gc_vm_lock();
     if (RB_LIKELY(st_lookup(finalizer_table, obj, &data))) {
         table = (VALUE)data;
         st_insert(finalizer_table, dest, table);
@@ -2811,6 +2812,7 @@ rb_gc_impl_copy_finalizer(void *objspace_ptr, VALUE dest, VALUE obj)
     else {
         rb_bug("rb_gc_copy_finalizer: FL_FINALIZE set but not found in finalizer_table: %s", rb_obj_info(obj));
     }
+    rb_gc_vm_unlock(lev);
 }
 
 static VALUE

gc/mmtk/mmtk.c

@@ -983,6 +983,7 @@ rb_gc_impl_copy_finalizer(void *objspace_ptr, VALUE dest, VALUE obj)
 
     if (!FL_TEST(obj, FL_FINALIZE)) return;
 
+    int lev = rb_gc_vm_lock();
     if (RB_LIKELY(st_lookup(objspace->finalizer_table, obj, &data))) {
         table = (VALUE)data;
         st_insert(objspace->finalizer_table, dest, table);
@@ -991,6 +992,7 @@ rb_gc_impl_copy_finalizer(void *objspace_ptr, VALUE dest, VALUE obj)
     else {
         rb_bug("rb_gc_copy_finalizer: FL_FINALIZE set but not found in finalizer_table: %s", rb_obj_info(obj));
     }
+    rb_gc_vm_unlock(lev);
 }
 
 static int

test/objspace/test_ractor.rb

@@ -33,4 +33,25 @@ def fin
       ractors.each(&:take)
     RUBY
   end
+
+  def test_copy_finalizer
+    assert_ractor(<<~'RUBY', require: 'objspace')
+      def fin
+        ->(id) { }
+      end
+      OBJ = Object.new
+      ObjectSpace.define_finalizer(OBJ, fin)
+      OBJ.freeze
+
+      ractors = 5.times.map do
+        Ractor.new do
+          10_000.times do
+            OBJ.clone
+          end
+        end
+      end
+
+      ractors.each(&:take)
+    RUBY
+  end
 end