Make CJBig2_Object::operator delete accept nullptr

core/src/fxcodec/jbig2/JBig2_Object.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 "JBig2_Object.h"
 #include "JBig2_Module.h"
 void *CJBig2_Object::operator new(size_t size, CJBig2_Module *pModule, const FX_CHAR* filename, int line)
 {
     CJBig2_Object *p;
     p = (CJBig2_Object *)pModule->JBig2_Malloc((FX_DWORD)size);
     p->m_pModule = pModule;
     return p;
 }
 void CJBig2_Object::operator delete(void *p, CJBig2_Module *pModule, const FX_CHAR* filename, int line)
 {
     pModule->JBig2_Free(p);
 }
 void *CJBig2_Object::operator new(size_t size, CJBig2_Module *pModule)
 {
     CJBig2_Object *p;
     p = (CJBig2_Object *)pModule->JBig2_Malloc((FX_DWORD)size);
     p->m_pModule = pModule;
     return p;
 }
 void CJBig2_Object::operator delete(void *p)
 {
-    ((CJBig2_Object *)p)->m_pModule->JBig2_Free(p);
+    if (p) {
+        ((CJBig2_Object *)p)->m_pModule->JBig2_Free(p);
+    }
 }
 void CJBig2_Object::operator delete(void *p, CJBig2_Module *pModule)
 {
     pModule->JBig2_Free(p);
 }
 void *CJBig2_Object::operator new[](size_t size, CJBig2_Module *pModule, size_t unit_size,
                                     const FX_CHAR* filename, int line)
 {
     void *p;
     uint8_t *pCur, *pEnd;
@@ skipping 17 matching lines @@
     p = (uint8_t *)pModule->JBig2_Malloc((FX_DWORD)size);
     pCur = (uint8_t *)p;
     pEnd = pCur + size;
     for(; pCur < pEnd; pCur += unit_size) {
         ((CJBig2_Object *)pCur)->m_pModule = pModule;
     }
     return p;
 }
 void CJBig2_Object::operator delete[](void* p)
 {
-    ((CJBig2_Object *)p)->m_pModule->JBig2_Free(p);
+    if (p) {
+        ((CJBig2_Object *)p)->m_pModule->JBig2_Free(p);
+    }
 }
 void CJBig2_Object::operator delete[](void *p, CJBig2_Module *pModule, size_t unit_size)
 {
     pModule->JBig2_Free(p);
 }