[BackgroundSync] Only allow SyncManager.register to occur from main frame

third_party/WebKit/Source/modules/background_sync/SyncManager.cpp

 // Copyright 2015 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "config.h"
 #include "modules/background_sync/SyncManager.h"
 
 #include "bindings/core/v8/CallbackPromiseAdapter.h"
 #include "bindings/core/v8/ScriptPromise.h"
 #include "bindings/core/v8/ScriptPromiseResolver.h"
@@ skipping 28 matching lines @@
 {
     ASSERT(registration);
 }
 
 ScriptPromise SyncManager::registerFunction(ScriptState* scriptState, ExecutionContext* context, const String& tag)
 {
     // TODO(jkarlin): Wait for the registration to become active instead of rejecting. See crbug.com/542437.
     if (!m_registration->active())
         return ScriptPromise::rejectWithDOMException(scriptState, DOMException::create(AbortError, "Registration failed - no active Service Worker"));
 
+    if (scriptState->executionContext()->isDocument()) {
+        Document* document = toDocument(scriptState->executionContext());
+        if (!document->domWindow() || !document->frame())
+            return ScriptPromise::rejectWithDOMException(scriptState, DOMException::create(InvalidStateError, "Document is detached from window."));
+        if (!document->frame()->isMainFrame())
+            return ScriptPromise::rejectWithDOMException(scriptState, DOMException::create(AbortError, "Registration failed - not called from a main frame."));
+    }
+
     ScriptPromiseResolver* resolver = ScriptPromiseResolver::create(scriptState);
     ScriptPromise promise = resolver->promise();
 
     WebSyncRegistration* webSyncRegistration = new WebSyncRegistration(
         WebSyncRegistration::UNREGISTERED_SYNC_ID /* id */,
         WebSyncRegistration::PeriodicityOneShot,
         tag,
         0 /* minPeriod */,
         WebSyncRegistration::NetworkStateOnline /* networkState */,
         WebSyncRegistration::PowerStateAuto /* powerState */
@@ skipping 12 matching lines @@
 
     return promise;
 }
 
 DEFINE_TRACE(SyncManager)
 {
     visitor->trace(m_registration);
 }
 
 } // namespace blink