From fc6bf61e4c90caa3db244d137efdb873d4876e48 Mon Sep 17 00:00:00 2001
From: Gleb Surikov <glebs.surikovs@gmail.com>
Date: Sat, 30 Mar 2024 21:10:17 +0200
Subject: [PATCH] [NTOS:CM] Avoid unnecessary ObDereferenceObject when handling
 an ObInsertObject failure (#6673)

In case of failure, ObInsertObject itself dereferences the object, so calling ObDereferenceObject one more time in the failure handler is redundant.

- Remove ObDereferenceObject call from CmpCreateRegistryRoot in case ObInsertObject fails.
- Add missing RootKey dereference if CmpCreateRegistryRoot failed to get the key cell (KeyCell).

CORE-17904
---
 ntoskrnl/config/cmsysini.c | 7 +++++--
 1 file changed, 5 insertions(+), 2 deletions(-)

diff --git a/ntoskrnl/config/cmsysini.c b/ntoskrnl/config/cmsysini.c
index d401c726e1b..a8ddc104073 100644
--- a/ntoskrnl/config/cmsysini.c
+++ b/ntoskrnl/config/cmsysini.c
@@ -1109,7 +1109,11 @@ CmpCreateRegistryRoot(VOID)
     /* Sanity check, and get the key cell */
     ASSERT((&CmiVolatileHive->Hive)->ReleaseCellRoutine == NULL);
     KeyCell = (PCM_KEY_NODE)HvGetCell(&CmiVolatileHive->Hive, RootIndex);
-    if (!KeyCell) return FALSE;
+    if (!KeyCell)
+    {
+        ObDereferenceObject(RootKey);
+        return FALSE;
+    }
 
     /* Create the KCB */
     RtlInitUnicodeString(&KeyName, L"\\REGISTRY");
@@ -1144,7 +1148,6 @@ CmpCreateRegistryRoot(VOID)
                             &CmpRegistryRootHandle);
     if (!NT_SUCCESS(Status))
     {
-        ObDereferenceObject(RootKey);
         return FALSE;
     }