Refine code to make it more safely.

Signed-off-by: Eric Dong <eric.dong@intel.com>
git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@13712 6f19259b-4bc3-4df7-8a09-765794883524

diff --git a/ShellPkg/Library/UefiShellDebug1CommandsLib/DmpStore.c b/ShellPkg/Library/UefiShellDebug1CommandsLib/DmpStore.c
index c85091d0a45092eadf93d7c6bac3a5ddb7032d33..8aafcced2401229c67a3c2476c81e0fa48f1dc24 100644 (file)
--- a/ShellPkg/Library/UefiShellDebug1CommandsLib/DmpStore.c
+++ b/ShellPkg/Library/UefiShellDebug1CommandsLib/DmpStore.c
@@ -59,7 +59,7 @@ GetAttrType (
     RetString = StrnCatGrow(&RetString, &BufLen, L"Invalid", 0);\r
   }\r
 \r
-  if (RetString[0] == L'+') {\r
+  if ((RetString != NULL) && (RetString[0] == L'+')) {\r
     CopyMem(RetString, RetString + 1, StrSize(RetString + 1));\r
   }\r
 \r