BaseTools/C/Common: Add/refine boundary checks for strcpy/strcat calls

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: Yonghong Zhu <yonghong.zhu@intel.com>
Contributed-under: TianoCore Contribution Agreement 1.1
Signed-off-by: Hao Wu <hao.a.wu@intel.com>
Reviewed-by: Liming Gao <liming.gao@intel.com>

2 files changed, 20 insertions, 13 deletions

diff --git a/BaseTools/Source/C/Common/CommonLib.c b/BaseTools/Source/C/Common/CommonLib.c
index 2f0aecf..4a62bec 100644
--- a/BaseTools/Source/C/Common/CommonLib.c
+++ b/BaseTools/Source/C/Common/CommonLib.c
@@ -1,7 +1,7 @@
 /** @file

 Common basic Library Functions

 

-Copyright (c) 2004 - 2016, Intel Corporation. All rights reserved.<BR>

+Copyright (c) 2004 - 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        

@@ -638,12 +638,22 @@ Returns:
       //

       RootPath = getcwd (NULL, 0);

       if (RootPath != NULL) {

-        strcat (mCommonLibFullPath, RootPath);

+        if (strlen (mCommonLibFullPath) + strlen (RootPath) > MAX_LONG_FILE_PATH - 1) {

+          Error (NULL, 0, 2000, "Invalid parameter", "RootPath is too long!");

+          free (RootPath);

+          return NULL;

+        }

+        strncat (mCommonLibFullPath, RootPath, MAX_LONG_FILE_PATH - strlen (mCommonLibFullPath) - 1);

         if (FileName[0] != '\\' && FileName[0] != '/') {

+          if (strlen (mCommonLibFullPath) + 1 > MAX_LONG_FILE_PATH - 1) {

+            Error (NULL, 0, 2000, "Invalid parameter", "RootPath is too long!");

+            free (RootPath);

+            return NULL;

+          }

           //

           // Attach directory separator

           //

-          strcat (mCommonLibFullPath, "\\");

+          strncat (mCommonLibFullPath, "\\", MAX_LONG_FILE_PATH - strlen (mCommonLibFullPath) - 1);

         }

         free (RootPath);

       }

@@ -673,7 +683,7 @@ Returns:
     //

     if ((PathPointer = strstr (mCommonLibFullPath, ":\\\\")) != NULL) {

       *(PathPointer + 2) = '\0';

-      strcat (mCommonLibFullPath, PathPointer + 3);

+      strncat (mCommonLibFullPath, PathPointer + 3, MAX_LONG_FILE_PATH - strlen (mCommonLibFullPath) - 1);

     }

     

     //

@@ -681,7 +691,7 @@ Returns:
     //

     while ((PathPointer = strstr (mCommonLibFullPath, ".\\")) != NULL) {

       *PathPointer = '\0';

-      strcat (mCommonLibFullPath, PathPointer + 2);

+      strncat (mCommonLibFullPath, PathPointer + 2, MAX_LONG_FILE_PATH - strlen (mCommonLibFullPath) - 1);

     }

         

     //

@@ -689,7 +699,7 @@ Returns:
     //

     while ((PathPointer = strstr (mCommonLibFullPath, "\\.\\")) != NULL) {

       *PathPointer = '\0';

-      strcat (mCommonLibFullPath, PathPointer + 2);

+      strncat (mCommonLibFullPath, PathPointer + 2, MAX_LONG_FILE_PATH - strlen (mCommonLibFullPath) - 1);

     }

 

     //

@@ -706,7 +716,7 @@ Returns:
         // Skip one directory

         //

         *PathPointer = '\0';

-        strcat (mCommonLibFullPath, NextPointer);

+        strncat (mCommonLibFullPath, NextPointer, MAX_LONG_FILE_PATH - strlen (mCommonLibFullPath) - 1);

       } else {

         //

         // No directory is found. Just break.

diff --git a/BaseTools/Source/C/Common/EfiUtilityMsgs.c b/BaseTools/Source/C/Common/EfiUtilityMsgs.c
index 7b4c231..5496a43 100644
--- a/BaseTools/Source/C/Common/EfiUtilityMsgs.c
+++ b/BaseTools/Source/C/Common/EfiUtilityMsgs.c
@@ -1,7 +1,7 @@
 /** @file

 EFI tools utility functions to display warning, error, and informational messages

 

-Copyright (c) 2004 - 2016, Intel Corporation. All rights reserved.<BR>

+Copyright (c) 2004 - 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

@@ -608,12 +608,9 @@ Returns:
   if (UtilityName != NULL) {

     if (strlen (UtilityName) >= sizeof (mUtilityName)) {

       Error (UtilityName, 0, 0, "application error", "utility name length exceeds internal buffer size");

-      strncpy (mUtilityName, UtilityName, sizeof (mUtilityName) - 1);

-      mUtilityName[sizeof (mUtilityName) - 1] = 0;

-      return ;

-    } else {

-      strcpy (mUtilityName, UtilityName);

     }

+    strncpy (mUtilityName, UtilityName, sizeof (mUtilityName) - 1);

+    mUtilityName[sizeof (mUtilityName) - 1] = 0;

   } else {

     Error (NULL, 0, 0, "application error", "SetUtilityName() called with NULL utility name");

   }