Use TmpStr as a backup, as StrCpy in BaseLib does not handle copy of two strings

that overlap.


git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@5559 6f19259b-4bc3-4df7-8a09-765794883524

1 files changed, 20 insertions, 2 deletions

diff --git a/MdeModulePkg/Universal/BdsDxe/BootMaint/BootOption.c b/MdeModulePkg/Universal/BdsDxe/BootMaint/BootOption.c
index 903ecfcdd3..020d63a8c6 100644
--- a/MdeModulePkg/Universal/BdsDxe/BootMaint/BootOption.c
+++ b/MdeModulePkg/Universal/BdsDxe/BootMaint/BootOption.c
@@ -1080,6 +1080,7 @@ BOpt_AppendFileName (
   UINTN   Size1;

   UINTN   Size2;

   CHAR16  *Str;

+  CHAR16  *TmpStr;

   CHAR16  *Ptr;

   CHAR16  *LastSlash;

 

@@ -1088,6 +1089,9 @@ BOpt_AppendFileName (
   Str   = AllocateZeroPool (Size1 + Size2 + sizeof (CHAR16));

   ASSERT (Str != NULL);

 

+  TmpStr = AllocateZeroPool (Size1 + Size2 + sizeof (CHAR16)); 

+  ASSERT (TmpStr != NULL);

+

   StrCat (Str, Str1);

   if (!((*Str == '\\') && (*(Str + 1) == 0))) {

     StrCat (Str, L"\\");

@@ -1104,13 +1108,25 @@ BOpt_AppendFileName (
       // DO NOT convert the .. if it is at the end of the string. This will

       // break the .. behavior in changing directories.

       //

-      StrCpy (LastSlash, Ptr + 3);

+

+      //

+      // Use TmpStr as a backup, as StrCpy in BaseLib does not handle copy of two strings 

+      // that overlap.

+      //

+      StrCpy (TmpStr, Ptr + 3);

+      StrCpy (LastSlash, TmpStr);

       Ptr = LastSlash;

     } else if (*Ptr == '\\' && *(Ptr + 1) == '.' && *(Ptr + 2) == '\\') {

       //

       // Convert a "\.\" to a "\"

       //

-      StrCpy (Ptr, Ptr + 2);

+

+      //

+      // Use TmpStr as a backup, as StrCpy in BaseLib does not handle copy of two strings 

+      // that overlap.

+      //

+      StrCpy (TmpStr, Ptr + 2);

+      StrCpy (Ptr, TmpStr);

       Ptr = LastSlash;

     } else if (*Ptr == '\\') {

       LastSlash = Ptr;

@@ -1119,6 +1135,8 @@ BOpt_AppendFileName (
     Ptr++;

   }

 

+  FreePool (TmpStr);

+  

   return Str;

 }