Bypass Service Worker for favicon loads

content/browser/loader/resource_dispatcher_host_impl.cc

 // Copyright (c) 2012 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.
 
 // See http://dev.chromium.org/developers/design-documents/multi-process-resource-loading
 
 #include "content/browser/loader/resource_dispatcher_host_impl.h"
 
 #include <algorithm>
 #include <set>
@@ skipping 1208 matching lines @@
   if (new_request->url().SchemeIs(url::kBlobScheme)) {
     // Hang on to a reference to ensure the blob is not released prior
     // to the job being started.
     storage::BlobProtocolHandler::SetRequestedBlobDataHandle(
         new_request.get(),
         filter_->blob_storage_context()->context()->GetBlobDataFromPublicURL(
             new_request->url()));
   }
 
   // Initialize the service worker handler for the request. We don't use
-  // ServiceWorker for synchronous loads to avoid renderer deadlocks.
+  // ServiceWorker for synchronous loads to avoid renderer deadlocks. We
+  // don't use ServiceWorker for favicons to avoid cache tainting.
+  bool is_favicon_load = request_data.resource_type == RESOURCE_TYPE_FAVICON;
   ServiceWorkerRequestHandler::InitializeHandler(
       new_request.get(),
       filter_->service_worker_context(),
       blob_context,
       child_id,
       request_data.service_worker_provider_id,
-      request_data.skip_service_worker || is_sync_load,
+      request_data.skip_service_worker || is_sync_load || is_favicon_load,
       request_data.fetch_request_mode,
       request_data.fetch_credentials_mode,
       request_data.resource_type,
       request_data.fetch_request_context_type,
       request_data.fetch_frame_type,
       request_data.request_body);
 
   // Have the appcache associate its extra info with the request.
   AppCacheInterceptor::SetExtraRequestInfo(
       new_request.get(), filter_->appcache_service(), child_id,
@@ skipping 902 matching lines @@
 
   // Add a flag to selectively bypass the data reduction proxy if the resource
   // type is not an image.
   if (request_data.resource_type != RESOURCE_TYPE_IMAGE)
     load_flags |= net::LOAD_BYPASS_DATA_REDUCTION_PROXY;
 
   return load_flags;
 }
 
 }  // namespace content