Merge 114350 - Stack overflow in CSS parser caused by recursive stylesheet import

Source/WebCore/css/CSSImportRule.cpp

 /*
  * (C) 1999-2003 Lars Knoll (knoll@kde.org)
  * (C) 2002-2003 Dirk Mueller (mueller@kde.org)
  * Copyright (C) 2002, 2005, 2006, 2008, 2009, 2010 Apple Inc. All rights reserved.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
@@ skipping 122 matching lines @@
     String absHref = m_strHref;
     if (!parentSheet->finalURL().isNull())
         // use parent styleheet's URL as the base URL
         absHref = KURL(parentSheet->finalURL(), m_strHref).string();
 
     // Check for a cycle in our import chain.  If we encounter a stylesheet
     // in our parent chain with the same URL, then just bail.
     CSSStyleSheet* rootSheet = parentSheet;
     for (CSSStyleSheet* sheet = parentSheet; sheet; sheet = sheet->parentStyleSheet()) {
         // FIXME: This is wrong if the finalURL was updated via document::updateBaseURL.
-        if (absHref == sheet->finalURL().string())
+        if (absHref == sheet->finalURL().string() || absHref == sheet->href())
             return;
         rootSheet = sheet;
     }
 
     ResourceRequest request(document->completeURL(absHref));
     if (parentSheet->isUserStyleSheet())
         m_cachedSheet = cachedResourceLoader->requestUserCSSStyleSheet(request, parentSheet->charset());
     else
         m_cachedSheet = cachedResourceLoader->requestCSSStyleSheet(request, parentSheet->charset());
     if (m_cachedSheet) {
@@ skipping 28 matching lines @@
     return result.toString();
 }
 
 void CSSImportRule::addSubresourceStyleURLs(ListHashSet<KURL>& urls)
 {
     if (m_styleSheet)
         addSubresourceURL(urls, m_styleSheet->baseURL());
 }
 
 } // namespace WebCore