Add pointer check for NULL before dereference it.

Signed-off-by: sfu5
Reviewed-by: xdu2
Reviewed-by: ydong10


git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@12514 6f19259b-4bc3-4df7-8a09-765794883524

NetworkPkg/IpSecDxe/IpSecConfigImpl.c

@@ -1,7 +1,7 @@
 /** @file
   The implementation of IPSEC_CONFIG_PROTOCOL.
 
-  Copyright (c) 2009 - 2010, Intel Corporation. All rights reserved.<BR>
+  Copyright (c) 2009 - 2011, Intel Corporation. All rights reserved.<BR>
 
   This program and the accompanying materials
   are licensed and made available under the terms and conditions of the BSD License
@@ -2196,6 +2196,10 @@ IpSecGetVariable (
                         VariableNameISizeNew,
                         VariableNameI
                         );
+      if (VariableNameI == NULL) {
+        Status = EFI_OUT_OF_RESOURCES;
+        break;
+      }
       VariableNameISize = VariableNameISizeNew;
 
       Status = gRT->GetNextVariableName (
@@ -2272,7 +2276,9 @@ IpSecGetVariable (
   }
 
 ON_EXIT:
-  FreePool (VariableNameI);
+  if (VariableNameI != NULL) {
+    FreePool (VariableNameI);
+  }
   return Status;
 }
 
@@ -2700,7 +2706,7 @@ IpSecCopyPolicyEntry (
     Buffer->Capacity += EntrySize;
     TempPoint         = AllocatePool (Buffer->Capacity);
     
-    if (Buffer->Ptr == NULL) {
+    if (TempPoint == NULL) {
       return EFI_OUT_OF_RESOURCES;
     }
     //