MdePkg BaseLib: Fix a corner case of Source and Destination overlap.

The overlap may happen when the address of Destination in
UnicodeStrToAsciiStr() or Source in AsciiStrToUnicodeStr()
is not two bytes aligned.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>

git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@15665 6f19259b-4bc3-4df7-8a09-765794883524

1 files changed, 4 insertions, 4 deletions

diff --git a/MdePkg/Library/BaseLib/String.c b/MdePkg/Library/BaseLib/String.c
index 227a0dc846..9505c5b21e 100644
--- a/MdePkg/Library/BaseLib/String.c
+++ b/MdePkg/Library/BaseLib/String.c
@@ -1,7 +1,7 @@
 /** @file

   Unicode and ASCII string primatives.

 

-  Copyright (c) 2006 - 2011, Intel Corporation. All rights reserved.<BR>

+  Copyright (c) 2006 - 2014, 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

@@ -1040,7 +1040,7 @@ UnicodeStrToAsciiStr (
   //

   // Source and Destination should not overlap

   //

-  ASSERT ((UINTN) ((CHAR16 *) Destination -  Source) > StrLen (Source));

+  ASSERT ((UINTN) (Destination - (CHAR8 *) Source) >= StrSize (Source));

   ASSERT ((UINTN) ((CHAR8 *) Source - Destination) > StrLen (Source));

 

 

@@ -2008,9 +2008,9 @@ AsciiStrToUnicodeStr (
   // Source and Destination should not overlap

   //

   ASSERT ((UINTN) ((CHAR8 *) Destination - Source) > AsciiStrLen (Source));

-  ASSERT ((UINTN) (Source - (CHAR8 *) Destination) > (AsciiStrLen (Source) * sizeof (CHAR16)));

+  ASSERT ((UINTN) (Source - (CHAR8 *) Destination) >= (AsciiStrSize (Source) * sizeof (CHAR16)));

+

 

- 

   ReturnValue = Destination;

   while (*Source != '\0') {

     *(Destination++) = (CHAR16) *(Source++);