BUG: IFSMGR_ParseOneElement Fails with Certain Character Combinations

• Microsoft Windows 95 Driver Development Kit (DDK)
• Microsoft Windows 98 Driver Development Kit (DDK)
• Microsoft Windows versions 95, 98

SYMPTOMS

In the Installable File System Manager (IFSMGR) VxD for Windows 95 version 4.0.950 and later, the IFSMGR_ParseOneElement function fails under certain conditions. The failure of this function under prescribed conditions is evident in the original version of Windows 95 (version 4.0.950), and all subsequent versions of Windows up to and including the original version of Windows 98.

The problem is manifest by an error message and subsequent termination of the application that is trying to create or rename a file using certain character-string combinations in a file name. This failure can be demonstrated by executing the following commands from an MS-DOS command prompt under Windows:

cd  \ 
md ..a
cd ..a
cd . 

This program has performed an illegal operation and will be terminated. Quit all programs, and then restart your computer.

• A string that is of the form "{2 consecutive decimal points}{1 or more printable ASCII characters}"



• A string that is of the form "{1 or more consecutive space characters}{1 or more decimal points}{1 or more printable ASCII characters}"

RESOLUTION

File system hook developers can intercept calls to IFSMGR_ParseOneElement and filter out strings of the above form. Any workaround should look for either two decimal points at the very beginning, or 1-n space characters followed by a decimal point.

STATUS

Microsoft has confirmed this to be a bug in the Microsoft products listed at the beginning of this article.

Additional query words:

Keywords          : kbDDK kbWinOS95 kbWinOS98 
Version           : WINDOWS:95,98; Win95:; Win98:
Platform          : Win95 WINDOWS Win98 
Issue type        : kbbug 

Last Reviewed: April 30, 1999