From f7a609c7fcbcc13f57e6b992e70f20149d582e6f Mon Sep 17 00:00:00 2001
From: Pierre Schweitzer <pierre@reactos.org>
Date: Sun, 27 Jan 2013 09:50:20 +0000
Subject: [PATCH] [NTOSKRNL] In ObpCheckTraverseAccess() first try to perform a
 fast traverse check before doing the entire access check.

svn path=/trunk/; revision=58239
---
 reactos/ntoskrnl/ob/obsecure.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/reactos/ntoskrnl/ob/obsecure.c b/reactos/ntoskrnl/ob/obsecure.c
index 3982258fcd6..fbc3c8e2ebb 100644
--- a/reactos/ntoskrnl/ob/obsecure.c
+++ b/reactos/ntoskrnl/ob/obsecure.c
@@ -301,6 +301,20 @@ ObpCheckTraverseAccess(IN PVOID Object,
         return FALSE;
     }
 
+    /* First try to perform a fast traverse check
+     * If it fails, then the entire access check will
+     * have to be done.
+     */
+    Result = SeFastTraverseCheck(SecurityDescriptor,
+                                 AccessState,
+                                 FILE_WRITE_DATA,
+                                 AccessMode);
+    if (Result)
+    {
+        ObReleaseObjectSecurity(SecurityDescriptor, SdAllocated);
+        return TRUE;
+    }
+
     /* Lock the security context */
     SeLockSubjectContext(&AccessState->SubjectSecurityContext);