Fix a bug that occurs when an object has the same object number with the root object

core/src/fpdfapi/fpdf_parser/fpdf_parser_parser.cpp

 // Copyright 2014 PDFium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
  
 // Original code copyright 2014 Foxit Software Inc. http://www.foxitsoftware.com
 
 #include "../../../include/fpdfapi/fpdf_parser.h"
 #include "../../../include/fpdfapi/fpdf_module.h"
 #include "../../../include/fpdfapi/fpdf_page.h"
 #include "../../../../third_party/numerics/safe_math.h"
@@ skipping 985 matching lines @@
     }
     return result;
 }
 FX_BOOL CPDF_Parser::LoadCrossRefV5(FX_FILESIZE pos, FX_FILESIZE& prev, FX_BOOL bMainXRef)
 {
     CPDF_Stream* pStream = (CPDF_Stream*)ParseIndirectObjectAt(m_pDocument, pos, 0, NULL);
     if (!pStream) {
         return FALSE;
     }
     if (m_pDocument) {
-        m_pDocument->InsertIndirectObject(pStream->m_ObjNum, pStream);
+        CPDF_Dictionary * pDict = m_pDocument->GetRoot();
+        if (!pDict || pDict->GetObjNum() != pStream->m_ObjNum) {
+            m_pDocument->InsertIndirectObject(pStream->m_ObjNum, pStream);
+        } else {
+            if (pStream->GetType() == PDFOBJ_STREAM) {
+                pStream->Release();
+            }
+            return FALSE;
+        }
     }
     if (pStream->GetType() != PDFOBJ_STREAM) {
         return FALSE;
     }
     prev = pStream->GetDict()->GetInteger(FX_BSTRC("Prev"));
     FX_INT32 size = pStream->GetDict()->GetInteger(FX_BSTRC("Size"));
     if (size < 0) {
         pStream->Release();
         return FALSE;
     }
@@ skipping 3401 matching lines @@
 {
     FX_INT32 iSize = m_childNode.GetSize();
     for (FX_INT32 i = 0; i < iSize; ++i) {
         CPDF_PageNode *pNode = (CPDF_PageNode*)m_childNode[i];
         if (pNode) {
             delete pNode;
         }
     }
     m_childNode.RemoveAll();
 }