src: fix memory leak for v8.serialize

When Buffer::New passes in existing data,
it cannot be garbage collected in js synchronous execution.

Fixes: https://github.com/nodejs/node/issues/40828
Refs: https://github.com/nodejs/node/issues/38300

PR-URL: https://github.com/nodejs/node/pull/42695
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: James M Snell <jasnell@gmail.com>
Reviewed-By: Minwoo Jung <nodecorelab@gmail.com>

1 files changed, 14 insertions, 2 deletions

diff --git a/src/node_buffer.cc b/src/node_buffer.cc
index 215bd8003aa..dcf5d84ca34 100644
--- a/src/node_buffer.cc
+++ b/src/node_buffer.cc
@@ -502,8 +502,20 @@ MaybeLocal<Object> New(Environment* env,
     }
   }
 
-  auto free_callback = [](char* data, void* hint) { free(data); };
-  return New(env, data, length, free_callback, nullptr);
+  EscapableHandleScope handle_scope(env->isolate());
+
+  auto free_callback = [](void* data, size_t length, void* deleter_data) {
+    free(data);
+  };
+  std::unique_ptr<BackingStore> bs =
+      v8::ArrayBuffer::NewBackingStore(data, length, free_callback, nullptr);
+
+  Local<ArrayBuffer> ab = v8::ArrayBuffer::New(env->isolate(), std::move(bs));
+
+  Local<Object> obj;
+  if (Buffer::New(env, ab, 0, length).ToLocal(&obj))
+    return handle_scope.Escape(obj);
+  return Local<Object>();
 }
 
 namespace {