SecurityPkg Variable: Support the new introduced PcdMaxAuthVariableSize.

1. If PcdMaxAuthVariableSize is set to 0, keep current behavior as is and
PcdMaxVariableSize used.
2. If PcdMaxAuthVariableSize is set to non 0, it will work on
authenticated variables.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Jiewen Yao <jiewen.yao@intel.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@17610 6f19259b-4bc3-4df7-8a09-765794883524

SecurityPkg/VariableAuthenticated/RuntimeDxe/VariableSmmRuntimeDxe.c

@@ -59,6 +59,10 @@ EFI_LOCK                         mVariableServicesLock;
 EDKII_VARIABLE_LOCK_PROTOCOL     mVariableLock;
 EDKII_VAR_CHECK_PROTOCOL         mVarCheck;
 
+#define MAX_NV_VARIABLE_SIZE (MAX (MAX (PcdGet32 (PcdMaxVariableSize), \
+                                        PcdGet32 (PcdMaxAuthVariableSize)), \
+                                   PcdGet32 (PcdMaxHardwareErrorVariableSize)))
+
 /**
   SecureBoot Hook for SetVariable.
 
@@ -931,7 +935,7 @@ SmmVariableReady (
   //
   // Allocate memory for variable communicate buffer.
   //
-  mVariableBufferPayloadSize = MAX (PcdGet32 (PcdMaxVariableSize), PcdGet32 (PcdMaxHardwareErrorVariableSize)) +
+  mVariableBufferPayloadSize = MAX_NV_VARIABLE_SIZE +
                                OFFSET_OF (SMM_VARIABLE_COMMUNICATE_VAR_CHECK_VARIABLE_PROPERTY, Name) - sizeof (VARIABLE_HEADER);
   mVariableBufferSize  = SMM_COMMUNICATE_HEADER_SIZE + SMM_VARIABLE_COMMUNICATE_HEADER_SIZE + mVariableBufferPayloadSize;
   mVariableBuffer      = AllocateRuntimePool (mVariableBufferSize);