ShellPkg/for: Fix potential null pointer deference

When "FOR %a %a IN A B C" is executed,
CurrentScriptFile->CurrentCommand->Data is NULL.
But the code assumes it's not NULL and tries to
deference it.

The patch fixes this issue.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Ruiyu Ni <ruiyu.ni@intel.com>
Reviewed-by: Jaben Carsey <jaben.carsey@intel.com>

1 files changed, 4 insertions, 2 deletions

diff --git a/ShellPkg/Library/UefiShellLevel1CommandsLib/For.c b/ShellPkg/Library/UefiShellLevel1CommandsLib/For.c
index 3db4bb5..9824977 100644
--- a/ShellPkg/Library/UefiShellLevel1CommandsLib/For.c
+++ b/ShellPkg/Library/UefiShellLevel1CommandsLib/For.c
@@ -2,7 +2,7 @@
   Main file for endfor and for shell level 1 functions.

 

   (C) Copyright 2015 Hewlett-Packard Development Company, L.P.<BR>

-  Copyright (c) 2009 - 2016, Intel Corporation. All rights reserved.<BR>

+  Copyright (c) 2009 - 2018, 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

@@ -624,7 +624,9 @@ ShellCommandRunFor (
   if (CurrentScriptFile != NULL && CurrentScriptFile->CurrentCommand != NULL) {

     Info = (SHELL_FOR_INFO*)CurrentScriptFile->CurrentCommand->Data;

     if (CurrentScriptFile->CurrentCommand->Reset) {

-      Info->CurrentValue  = (CHAR16*)Info->Set;

+      if (Info != NULL) {

+        Info->CurrentValue = (CHAR16*)Info->Set;

+      }

       FirstPass = TRUE;

       CurrentScriptFile->CurrentCommand->Reset = FALSE;

     }