Enhance SmbiosDxe driver:

1. If string length exceeds 65535 bytes, return error. So infinite loop will not happen because of UINTN overflow.
2. When a SMBIOS entry is added or updated, check if the total length of SMBIOS table exceeds 65535 bytes, if it happens, return error.

Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Elvin Li <elvin.li@intel.com>

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@13290 6f19259b-4bc3-4df7-8a09-765794883524

MdeModulePkg/Universal/SmbiosDxe/SmbiosDxe.h

@@ -1,7 +1,7 @@
 /** @file
   This code supports the implementation of the Smbios protocol
   
-Copyright (c) 2009 - 2011, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2009 - 2012, Intel Corporation. All rights reserved.<BR>
 This program and the accompanying materials                          
 are licensed and made available under the terms and conditions of the BSD License         
 which accompanies this distribution.  The full text of the license may be found at        
@@ -31,6 +31,13 @@ WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
 #include <Library/UefiBootServicesTableLib.h>
 #include <Library/PcdLib.h>
 
+//
+// The length of the entire structure table (including all strings) must be reported
+// in the Structure Table Length field of the SMBIOS Structure Table Entry Point,
+// which is a WORD field limited to 65,535 bytes.
+//
+#define SMBIOS_TABLE_MAX_LENGTH 0xFFFF
+
 #define SMBIOS_INSTANCE_SIGNATURE SIGNATURE_32 ('S', 'B', 'i', 's')
 typedef struct {
   UINT32                Signature;