Add check for mismatching item and document sequence numbers.

content/browser/web_contents/web_contents_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.
 
 #include "content/browser/web_contents/web_contents_impl.h"
 
 #include <stddef.h>
 
 #include <cmath>
 #include <utility>
@@ skipping 63 matching lines @@
 #include "content/browser/web_contents/web_contents_view_guest.h"
 #include "content/browser/webui/generic_handler.h"
 #include "content/browser/webui/web_ui_controller_factory_registry.h"
 #include "content/browser/webui/web_ui_impl.h"
 #include "content/common/browser_plugin/browser_plugin_constants.h"
 #include "content/common/browser_plugin/browser_plugin_messages.h"
 #include "content/common/frame_messages.h"
 #include "content/common/input/web_input_event_traits.h"
 #include "content/common/input_messages.h"
 #include "content/common/page_messages.h"
+#include "content/common/page_state_serialization.h"
 #include "content/common/site_isolation_policy.h"
 #include "content/common/ssl_status_serialization.h"
 #include "content/common/view_messages.h"
 #include "content/public/browser/ax_event_notification_details.h"
 #include "content/public/browser/browser_context.h"
 #include "content/public/browser/browser_plugin_guest_manager.h"
 #include "content/public/browser/content_browser_client.h"
 #include "content/public/browser/devtools_agent_host.h"
 #include "content/public/browser/download_manager.h"
 #include "content/public/browser/download_url_parameters.h"
@@ skipping 4433 matching lines @@
     return;
 
   if (page_state == frame_entry->page_state())
     return;  // Nothing to update.
 
   if (!page_state.IsValid()) {
     // Temporarily generate a minidump to diagnose https://crbug.com/568703.
     base::debug::DumpWithoutCrashing();
     NOTREACHED() << "Shouldn't set an empty PageState.";
   }
+
+  // The document_sequence_number and item_sequence_number recorded in the
+  // FrameNavigationEntry should not differ from the one coming with the update,
+  // since it must come from the same document. Do not update it if a difference
+  // is detected, as this indicates that |frame_entry| is not the correct one.
+  ExplodedPageState exploded_state;
+  if (!DecodePageState(page_state.ToEncodedData(), &exploded_state))
+    return;
+
+  if (exploded_state.top.document_sequence_number !=
+          frame_entry->document_sequence_number() ||
+      exploded_state.top.item_sequence_number !=
+          frame_entry->item_sequence_number()) {
+    return;
+  }
+
   frame_entry->set_page_state(page_state);
   controller_.NotifyEntryChanged(entry);
 }
 
 void WebContentsImpl::UpdateTitle(RenderFrameHost* render_frame_host,
                                   int32_t page_id,
                                   const base::string16& title,
                                   base::i18n::TextDirection title_direction) {
   // If we have a title, that's a pretty good indication that we've started
   // getting useful data.
@@ skipping 667 matching lines @@
   for (RenderViewHost* render_view_host : render_view_host_set)
     render_view_host->OnWebkitPreferencesChanged();
 }
 
 void WebContentsImpl::SetJavaScriptDialogManagerForTesting(
     JavaScriptDialogManager* dialog_manager) {
   dialog_manager_ = dialog_manager;
 }
 
 }  // namespace content