Set m_pLinearized to NULL after release

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 1479 matching lines @@
     }
     m_pLinearized = m_Syntax.GetObject(NULL, objnum, gennum, 0);
     if (!m_pLinearized) {
         return FALSE;
     }
     if (m_pLinearized->GetDict() && m_pLinearized->GetDict()->GetElement(FX_BSTRC("Linearized"))) {
         m_Syntax.GetNextWord(bIsNumber);
         CPDF_Object *pLen = m_pLinearized->GetDict()->GetElement(FX_BSTRC("L"));
         if (!pLen) {
             m_pLinearized->Release();
+            m_pLinearized = NULL;
             return FALSE;
         }
         if (pLen->GetInteger() != (int)pFileAccess->GetSize()) {
             return FALSE;
         }
         CPDF_Object *pNo = m_pLinearized->GetDict()->GetElement(FX_BSTRC("P"));
         if (pNo && pNo->GetType() == PDFOBJ_NUMBER) {
             m_dwFirstPageNo = pNo->GetInteger();
         }
         CPDF_Object *pTable = m_pLinearized->GetDict()->GetElement(FX_BSTRC("T"));
@@ skipping 2902 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();
 }