Refine code to make it more safely.

Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Eric Dong <eric.dong@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>
git-svn-id: https://svn.code.sf.net/p/edk2/code/trunk/edk2@15720 6f19259b-4bc3-4df7-8a09-765794883524

diff --git a/MdeModulePkg/Universal/SetupBrowserDxe/Expression.c b/MdeModulePkg/Universal/SetupBrowserDxe/Expression.c
index 3b0172d1245ddfffa225b640d2d5e0b348a17ba8..e8829c1855fcbe50ca683893452345f6204e21b2 100644 (file)
--- a/MdeModulePkg/Universal/SetupBrowserDxe/Expression.c
+++ b/MdeModulePkg/Universal/SetupBrowserDxe/Expression.c
@@ -1323,6 +1323,7 @@ IfrCatenate (
   UINTN          Size;\r
   UINT16         Length0;\r
   UINT16         Length1;\r
+  UINT8          *TmpBuf;\r
 \r
   //\r
   // String[0] - The second string\r
@@ -1378,8 +1379,12 @@ IfrCatenate (
     Result->Buffer = AllocateZeroPool (Result->BufferLen);\r
     ASSERT (Result->Buffer != NULL);\r
 \r
-    CopyMem (Result->Buffer, GetBufferForValue(&Value[0]), Length0);\r
-    CopyMem (&Result->Buffer[Length0], GetBufferForValue(&Value[1]), Length1);\r
+    TmpBuf = GetBufferForValue(&Value[0]);\r
+    ASSERT (TmpBuf != NULL);\r
+    CopyMem (Result->Buffer, TmpBuf, Length0);\r
+    TmpBuf = GetBufferForValue(&Value[1]);\r
+    ASSERT (TmpBuf != NULL);\r
+    CopyMem (&Result->Buffer[Length0], TmpBuf, Length1);\r
   }\r
 Done:\r
   if (Value[0].Buffer != NULL) {\r