ofz#4539 depth protect mathtype parser

Change-Id: I46e12f52d56e7802b676309207904b4d1894d236
Reviewed-on: https://gerrit.libreoffice.org/45928Tested-by: Jenkins <ci@libreoffice.org>
Reviewed-by: Caolán McNamara <caolanm@redhat.com>
Tested-by: Caolán McNamara <caolanm@redhat.com>

starmath/inc/parse.hxx

@@ -41,6 +41,24 @@ class SmParser
                     m_nColOff; // 0-based
     bool            m_bImportSymNames,
                     m_bExportSymNames;
+    sal_Int32       m_nParseDepth;
+
+    class DepthProtect
+    {
+    private:
+        sal_Int32& m_rParseDepth;
+    public:
+        DepthProtect(sal_Int32& rParseDepth)
+            : m_rParseDepth(rParseDepth)
+        {
+            ++m_rParseDepth;
+        }
+        bool TooDeep() const { return m_rParseDepth > 2048; }
+        ~DepthProtect()
+        {
+            --m_rParseDepth;
+        }
+    };
 
     // map of used symbols (used to reduce file size by exporting only actually used symbols)
     std::set< OUString >   m_aUsedSymbols;

starmath/source/mathmlimport.cxx

@@ -297,11 +297,11 @@ ErrCode SmXMLImportWrapper::ReadThroughComponent(
         if ( pFilter && pFilter->GetSuccess() )
             nError = ERRCODE_NONE;
     }
-    catch( xml::sax::SAXParseException& r )
+    catch (const xml::sax::SAXParseException& r)
     {
         // sax parser sends wrapped exceptions,
         // try to find the original one
-        xml::sax::SAXException aSaxEx = *static_cast<xml::sax::SAXException*>(&r);
+        xml::sax::SAXException aSaxEx = *static_cast<const xml::sax::SAXException*>(&r);
         bool bTryChild = true;
 
         while( bTryChild )
@@ -320,7 +320,7 @@ ErrCode SmXMLImportWrapper::ReadThroughComponent(
         if ( bEncrypted )
             nError = ERRCODE_SFX_WRONGPASSWORD;
     }
-    catch( const xml::sax::SAXException& r )
+    catch (const xml::sax::SAXException& r)
     {
         packages::zip::ZipIOException aBrokenPackage;
         if ( r.WrappedException >>= aBrokenPackage )
@@ -329,11 +329,14 @@ ErrCode SmXMLImportWrapper::ReadThroughComponent(
         if ( bEncrypted )
             nError = ERRCODE_SFX_WRONGPASSWORD;
     }
-    catch( packages::zip::ZipIOException& )
+    catch (const packages::zip::ZipIOException&)
     {
         nError = ERRCODE_IO_BROKENPACKAGE;
     }
-    catch( io::IOException& )
+    catch (const io::IOException&)
+    {
+    }
+    catch (const std::range_error&)
     {
     }
 
@@ -3131,7 +3134,9 @@ extern "C" SAL_DLLPUBLIC_EXPORT bool SAL_CALL TestImportMML(SvStream &rStream)
     //to update the properties, which throws cause the properties are uninitialized
     xDocSh->SetLoading(SfxLoadedFlags::NONE);
 
-    auto nRet = SmXMLImportWrapper::ReadThroughComponent(xStream, xModel, xContext, xInfoSet, "com.sun.star.comp.Math.XMLImporter", false);
+    ErrCode nRet = ERRCODE_SFX_DOLOADFAILED;
+
+    nRet = SmXMLImportWrapper::ReadThroughComponent(xStream, xModel, xContext, xInfoSet, "com.sun.star.comp.Math.XMLImporter", false);
 
     xDocSh->SetLoading(SfxLoadedFlags::ALL);