From 02c3f0fa12720e3962587014c8d825a20dd7106e Mon Sep 17 00:00:00 2001
From: Michael Martin <michael.martin@reactos.org>
Date: Tue, 27 Apr 2010 13:41:37 +0000
Subject: [PATCH] [ntoskrnl/io] - Check for null pointers before attempting to
 copy or free memory.

svn path=/trunk/; revision=47049
---
 reactos/ntoskrnl/io/iomgr/deviface.c | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/reactos/ntoskrnl/io/iomgr/deviface.c b/reactos/ntoskrnl/io/iomgr/deviface.c
index 8a8db7a843f..7d97336cc16 100644
--- a/reactos/ntoskrnl/io/iomgr/deviface.c
+++ b/reactos/ntoskrnl/io/iomgr/deviface.c
@@ -884,7 +884,8 @@ IoGetDeviceInterfaces(IN CONST GUID *InterfaceClassGuid,
 NextReferenceString:
             ExFreePool(ReferenceBi);
             ReferenceBi = NULL;
-            ExFreePool(bip);
+            if (bip)
+                ExFreePool(bip);
             bip = NULL;
             if (ReferenceKey != INVALID_HANDLE_VALUE)
             {
@@ -921,8 +922,11 @@ NextReferenceString:
             Status = STATUS_INSUFFICIENT_RESOURCES;
             goto cleanup;
         }
-        RtlCopyMemory(NewBuffer, ReturnBuffer.Buffer, ReturnBuffer.Length);
-        ExFreePool(ReturnBuffer.Buffer);
+        if (ReturnBuffer.Buffer)
+        {
+            RtlCopyMemory(NewBuffer, ReturnBuffer.Buffer, ReturnBuffer.Length);
+            ExFreePool(ReturnBuffer.Buffer);
+        }
         ReturnBuffer.Buffer = NewBuffer;
     }
     ReturnBuffer.Buffer[ReturnBuffer.Length / sizeof(WCHAR)] = UNICODE_NULL;