ShellPkg: add array index check for shell delay option

BZ: https://bugzilla.tianocore.org/show_bug.cgi?id=1528

Shell delay option without parameters do not check the
index of shell parameter argv. Add index check to avoid
invalid pointer references.

Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Zhichao Gao <zhichao.gao@intel.com>
Cc: Liming Gao <liming.gao@intel.com>
Cc: Ray Ni <ray.ni@intel.com>
Reviewed-by: Jaben Carsey <jaben.carsey@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>

diff --git a/ShellPkg/Application/Shell/Shell.c b/ShellPkg/Application/Shell/Shell.c
index 104f4c896130e3e9c4c14863df3c07e7ecb4ca54..ec344137d355e2dad689bc54f71c3839a896d7f5 100644 (file)
--- a/ShellPkg/Application/Shell/Shell.c
+++ b/ShellPkg/Application/Shell/Shell.c
@@ -1,7 +1,7 @@
 /** @file\r
   This is THE shell (application)\r
 \r
-  Copyright (c) 2009 - 2018, Intel Corporation. All rights reserved.<BR>\r
+  Copyright (c) 2009 - 2019, Intel Corporation. All rights reserved.<BR>\r
   (C) Copyright 2013-2014 Hewlett-Packard Development Company, L.P.<BR>\r
   Copyright 2015-2018 Dell Technologies.<BR>\r
   This program and the accompanying materials\r
@@ -1002,7 +1002,11 @@ ProcessCommandLine(
                                  ) == 0) {\r
       ShellInfoObject.ShellInitSettings.BitUnion.Bits.Delay        = TRUE;\r
       // Check for optional delay value following "-delay"\r
-      DelayValueStr = gEfiShellParametersProtocol->Argv[LoopVar + 1];\r
+      if ((LoopVar + 1) >= gEfiShellParametersProtocol->Argc) {\r
+        DelayValueStr = NULL;\r
+      } else {\r
+        DelayValueStr = gEfiShellParametersProtocol->Argv[LoopVar + 1];\r
+      }\r
       if (DelayValueStr != NULL){\r
         if (*DelayValueStr == L':') {\r
           DelayValueStr++;\r