MdeModulePkg/VariableSmm: Add func for Primary Buffer valid check

Add a new function (VariableSmmIsPrimaryBufferValid) to check
Primary Buffer valid or not.

original function (VariableSmmIsBufferOutsideSmmValid) is used to
check the buffer outside MMRAM.

Signed-off-by: Jiaxin Wu <jiaxin.wu@intel.com>
Cc: Liming Gao <gaoliming@byosoft.com.cn>
Cc: Ray Ni <ray.ni@intel.com>
Cc: Star Zeng <star.zeng@intel.com>
Cc: Hongbin1 Zhang <hongbin1.zhang@intel.com>
Cc: Wei6 Xu <wei6.xu@intel.com>
Cc: Dun Tan <dun.tan@intel.com>
Cc: Yuanhao Xie <yuanhao.xie@intel.com>

MdeModulePkg/Universal/Variable/RuntimeDxe/PrivilegePolymorphic.h

@@ -7,7 +7,7 @@
   vs. non-privileged driver code.
 
   Copyright (c) 2017, Red Hat, Inc.<BR>
-  Copyright (c) 2010 - 2018, Intel Corporation. All rights reserved.<BR>
+  Copyright (c) 2010 - 2024, Intel Corporation. All rights reserved.<BR>
 
   SPDX-License-Identifier: BSD-2-Clause-Patent
 **/
@@ -122,6 +122,21 @@ MmVariableServiceInitialize (
   VOID
   );
 
+/**
+  This function checks if the communication buffer is valid.
+
+  @param Buffer The buffer start address to be checked.
+  @param Length The buffer length to be checked.
+
+  @retval TRUE  This buffer is valid.
+  @retval FALSE This buffer is not valid.
+**/
+BOOLEAN
+VariableSmmIsPrimaryBufferValid (
+  IN EFI_PHYSICAL_ADDRESS  Buffer,
+  IN UINT64                Length
+  );
+
 /**
   This function checks if the buffer is valid per processor architecture and
   does not overlap with SMRAM.

MdeModulePkg/Universal/Variable/RuntimeDxe/VariableSmm.c

@@ -14,7 +14,7 @@
   VariableServiceSetVariable(), VariableServiceQueryVariableInfo(), ReclaimForOS(),
   SmmVariableGetStatistics() should also do validation based on its own knowledge.
 
-Copyright (c) 2010 - 2019, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2010 - 2024, Intel Corporation. All rights reserved.<BR>
 Copyright (c) 2018, Linaro, Ltd. All rights reserved.<BR>
 SPDX-License-Identifier: BSD-2-Clause-Patent
 
@@ -497,8 +497,8 @@ SmmVariableHandler (
     return EFI_SUCCESS;
   }
 
-  if (!VariableSmmIsBufferOutsideSmmValid ((UINTN)CommBuffer, TempCommBufferSize)) {
+  if (!VariableSmmIsPrimaryBufferValid ((UINTN)CommBuffer, TempCommBufferSize)) {
-    DEBUG ((DEBUG_ERROR, "SmmVariableHandler: SMM communication buffer in SMRAM or overflow!\n"));
+    DEBUG ((DEBUG_ERROR, "SmmVariableHandler: SMM Primary Buffer (CommBuffer) is not valid!\n"));
     return EFI_SUCCESS;
   }
 

MdeModulePkg/Universal/Variable/RuntimeDxe/VariableStandaloneMm.c

@@ -2,7 +2,7 @@
 
   Parts of the SMM/MM implementation that are specific to standalone MM
 
-Copyright (c) 2011 - 2018, Intel Corporation. All rights reserved. <BR>
+Copyright (c) 2011 - 2024, Intel Corporation. All rights reserved. <BR>
 Copyright (c) 2018, Linaro, Ltd. All rights reserved. <BR>
 SPDX-License-Identifier: BSD-2-Clause-Patent
 
@@ -10,6 +10,24 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
 
 #include "Variable.h"
 
+/**
+  This function checks if the Primary Buffer (CommBuffer) is valid.
+
+  @param Buffer The buffer start address to be checked.
+  @param Length The buffer length to be checked.
+
+  @retval TRUE  This buffer is valid.
+  @retval FALSE This buffer is not valid.
+**/
+BOOLEAN
+VariableSmmIsPrimaryBufferValid (
+  IN EFI_PHYSICAL_ADDRESS  Buffer,
+  IN UINT64                Length
+  )
+{
+  return TRUE;
+}
+
 /**
   This function checks if the buffer is valid per processor architecture and
   does not overlap with SMRAM.

MdeModulePkg/Universal/Variable/RuntimeDxe/VariableTraditionalMm.c

@@ -2,7 +2,7 @@
 
   Parts of the SMM/MM implementation that are specific to traditional MM
 
-Copyright (c) 2011 - 2018, Intel Corporation. All rights reserved. <BR>
+Copyright (c) 2011 - 2024, Intel Corporation. All rights reserved. <BR>
 Copyright (c) 2018, Linaro, Ltd. All rights reserved. <BR>
 SPDX-License-Identifier: BSD-2-Clause-Patent
 
@@ -12,6 +12,24 @@ SPDX-License-Identifier: BSD-2-Clause-Patent
 #include <Library/SmmMemLib.h>
 #include "Variable.h"
 
+/**
+  This function checks if the Primary Buffer (CommBuffer) is valid.
+
+  @param Buffer The buffer start address to be checked.
+  @param Length The buffer length to be checked.
+
+  @retval TRUE  This buffer is valid.
+  @retval FALSE This buffer is not valid.
+**/
+BOOLEAN
+VariableSmmIsPrimaryBufferValid (
+  IN EFI_PHYSICAL_ADDRESS  Buffer,
+  IN UINT64                Length
+  )
+{
+  return SmmIsBufferOutsideSmmValid (Buffer, Length);
+}
+
 /**
   This function checks if the buffer is valid per processor architecture and
   does not overlap with SMRAM.