[PATCH 10/17] BaseTools/GenBootSector: Add/refine boundary checks for strcpy/strcat

[Hao Wu <hao.a.wu@intel.com>]

Add checks to ensure when the destination string buffer is of fixed
size, the strcpy/strcat functions calls will not access beyond the
boundary.

Cc: Liming Gao <liming.gao@intel.com>
Cc: Yonghong Zhu <yonghong.zhu@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Hao Wu <hao.a.wu@intel.com>
---
 BaseTools/Source/C/GenBootSector/GenBootSector.c | 17 +++++++++++++++--
 1 file changed, 15 insertions(+), 2 deletions(-)

diff --git a/BaseTools/Source/C/GenBootSector/GenBootSector.c b/BaseTools/Source/C/GenBootSector/GenBootSector.c
index 3908c589af..c02de49ba2 100644
--- a/BaseTools/Source/C/GenBootSector/GenBootSector.c
+++ b/BaseTools/Source/C/GenBootSector/GenBootSector.c
@@ -4,7 +4,7 @@ Reading/writing MBR/DBR.
     If we write MBR to disk, we just update the MBR code and the partition table wouldn't be over written.
     If we process DBR, we will patch MBR to set first partition active if no active partition exists.
     
-Copyright (c) 2006 - 2016, Intel Corporation. All rights reserved.<BR>
+Copyright (c) 2006 - 2017, 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        
@@ -631,6 +631,14 @@ GetPathInfo (
 	return ErrorSuccess;
   } 
 
+  //
+  // Check the path length
+  //
+  if (strlen (PathInfo->Path) >= (sizeof (PathInfo->PhysicalPath) / sizeof (PathInfo->PhysicalPath[0]))) {
+    fprintf (stderr, "ERROR, Path is too long for - %s", PathInfo->Path);
+    return ErrorPath;
+  }
+
   PathInfo->Type = PathFile;
   if (PathInfo->Input) {
     //
@@ -644,7 +652,12 @@ GetPathInfo (
     fclose (f);
   }
   PathInfo->Type = PathFile;
-  strcpy(PathInfo->PhysicalPath, PathInfo->Path);
+  strncpy(
+    PathInfo->PhysicalPath,
+    PathInfo->Path,
+    sizeof (PathInfo->PhysicalPath) / sizeof (PathInfo->PhysicalPath[0]) - 1
+    );
+  PathInfo->PhysicalPath[sizeof (PathInfo->PhysicalPath) / sizeof (PathInfo->PhysicalPath[0]) - 1] = 0;
 
   return ErrorSuccess;
 }    
-- 
2.12.0.windows.1