[GitHub] [xerces-c] rouault opened a new pull request, #51: [XERCESC-2241] Fix integer overflows in DFAContentModel class

[GitBox]

rouault opened a new pull request, #51:
URL: https://github.com/apache/xerces-c/pull/51

   On .xsd files like the following ones (generated by ossfuzz, so broken), 
integer overflows can happen in DFAContentModel::countLeafNodes() and 
DFAContentModel::buildDFA() which can later cause out-of-bounds access.
   
   Found in https://bugs.chromium.org/p/oss-fuzz/issues/detail?id=52025
   
   ```
   <xs:schema xmlns:xs="http://www.w3.org/2001/XMLSchema";
              xmlns:myns="http://myns";
              targetNamespace="http://myns";
              elementFormDefault="qualified" attributeFormDefault="unqualified">
   
   <xs:element name="main_elt">
     <xs:complexType>
        <xs:sequence>
           <xs:group ref="myns:mygroup" minOccurs="32767" maxOccurs="1"/>
         </xs:sequence>
     </xs:complexType>
   </xs:element>
   
   <xs:group name="mygroup">
     <xs:sequence>
         <!-- related to https://issues.apache.org/jira/browse/XERCESC-1051 -->
         <xs:element name="elt" maxOccurs="33333">
           <xs:complexType>
               <xs:sequence>
    ame="x" type="xs:int" maxOccurs="1"/>
               </xs:sequence>
           </xs:complexType>
         </xs:element>
     </xs:sequence>
   </xs:group>
   
   </xs:schema>
   ```


-- 
This is an automated message from the Apache Git Service.
To respond to the message, please log on to GitHub and use the
URL above to go to the specific comment.

To unsubscribe, e-mail: c-dev-unsubscr...@xerces.apache.org

For queries about this service, please contact Infrastructure at:
us...@infra.apache.org


---------------------------------------------------------------------
To unsubscribe, e-mail: c-dev-unsubscr...@xerces.apache.org
For additional commands, e-mail: c-dev-h...@xerces.apache.org