sqlite: fix segfault SQLTagStore when db handle is garbage collected

src/node_sqlite.cc

@@ -2718,6 +2718,7 @@ BaseObjectPtr<SQLTagStore> SQLTagStore::Create(
            .ToLocal(&obj)) {
     return nullptr;
   }
+  obj->SetInternalField(kDatabaseObject, database->object());
   return MakeBaseObject<SQLTagStore>(env, obj, std::move(database), capacity);
 }
 
@@ -2728,9 +2729,8 @@ void SQLTagStore::CapacityGetter(const FunctionCallbackInfo<Value>& args) {
 }
 
 void SQLTagStore::DatabaseGetter(const FunctionCallbackInfo<Value>& args) {
-  SQLTagStore* store;
-  ASSIGN_OR_RETURN_UNWRAP(&store, args.This());
-  args.GetReturnValue().Set(store->database_->object());
+  args.GetReturnValue().Set(
+      args.This()->GetInternalField(kDatabaseObject).As<Value>());
 }
 
 void SQLTagStore::SizeGetter(const FunctionCallbackInfo<Value>& args) {

src/node_sqlite.h

@@ -304,6 +304,11 @@ class Session : public BaseObject {
 
 class SQLTagStore : public BaseObject {
  public:
+  enum InternalFields {
+    kDatabaseObject = BaseObject::kInternalFieldCount,
+    kInternalFieldCount
+  };
+
   SQLTagStore(Environment* env,
               v8::Local<v8::Object> object,
               BaseObjectWeakPtr<DatabaseSync> database,

test/parallel/test-sqlite-template-tag.js

@@ -1,4 +1,6 @@
 'use strict';
+// Flags: --expose-gc
+
 const { skipIfSQLiteMissing } = require('../common');
 skipIfSQLiteMissing();
 
@@ -124,3 +126,35 @@ test('sql error messages are descriptive', () => {
     message: /no such table/i,
   });
 });
+
+test('a tag store keeps the database alive by itself', () => {
+  const sql = new DatabaseSync(':memory:').createTagStore();
+
+  sql.db.exec('CREATE TABLE test (data INTEGER)');
+
+  global.gc();
+
+  // eslint-disable-next-line no-unused-expressions
+  sql.run`INSERT INTO test (data) VALUES (1)`;
+});
+
+test('tag store prevents circular reference leaks', async () => {
+  const { gcUntil } = require('../common/gc');
+
+  const before = process.memoryUsage().heapUsed;
+
+  // Create many SQLTagStore + DatabaseSync pairs with circular references
+  for (let i = 0; i < 1000; i++) {
+    const sql = new DatabaseSync(':memory:').createTagStore();
+    sql.db.exec('CREATE TABLE test (data INTEGER)');
+    // eslint-disable-next-line no-void
+    sql.db.setAuthorizer(() => void sql.db);
+  }
+
+  // GC until memory stabilizes or give up after 20 attempts
+  await gcUntil('tag store leak check', () => {
+    const after = process.memoryUsage().heapUsed;
+    // Memory should not grow significantly (allow 50% margin for noise)
+    return after < before * 1.5;
+  }, 20);
+});