FIX: Integrated Security Sprocs Have Race Condition Between Threads That Can Result in an Access Violation (238621)



The information in this article applies to:

  • Microsoft SQL Server 6.5

This article was previously published under Q238621
BUG #: 18739 (SQLBUG_65)

SYMPTOMS

Integrated security extended stored procedures have a race condition that can result in handled access violations (AVs) within the xproc, server handled exceptions, ODS AVs, and unhandled exceptions. Procedures with this problem include:

xp_logininfo
xp_enumgroups
xp_revokelogin
xp_grantlogin

For most situations, the symptoms of the problem appear in the SQL ERRORLOG with the message similar to the following:
Error : 0, Severity: 19, State: 0
Stored function 'xp_logininfo' in the library 'xplog60.dll' generated access violation; SQL Server is terminating process 25
This error message indicates that an access violation was caught by SQL Server when executing the extended stored procedure within the context of the worker thread that executed the function in the xproc DLL.

RESOLUTION

A supported fix is now available from Microsoft, but it is only intended to correct the problem that is described in this article. Apply it only to computers that are experiencing this specific problem. This fix may receive additional testing. Therefore, if you are not severely affected by this problem, Microsoft recommends that you wait for the next SQL Server service pack that contains this hotfix.

To resolve this problem immediately, contact Microsoft Product Support Services to obtain the fix. For a complete list of Microsoft Product Support Services phone numbers and information about support costs, visit the following Microsoft Web site:NOTE: In special cases, charges that are ordinarily incurred for support calls may be canceled if a Microsoft Support Professional determines that a specific update will resolve your problem. The typical support costs will apply to additional support questions and issues that do not qualify for the specific update in question.

The English version of this fix should have the following file attributes or later:
   Version      File name      Platform
   ---------------------------------------------------------
   6.50.480     sql480i.exe    Intel
                sql480a.exe    Alpha
				
NOTE: Due to file dependencies, the most recent hotfix or feature that contains the preceding files may also contain additional files.

STATUS

Microsoft has confirmed this to be a problem in SQL Server 6.5.

MORE INFORMATION

The symptoms of the problem can exceed just the handled preceding AV and be unpredictable. Other symptoms seen during testing include EXCEPTION_ACCESS_VIOLATION and EXCEPTION_PRIV_INSTRUCTION exceptions handled by the server, ODS AVs, and even an unhandled exception that can bring down the server.

Modification Type:MinorLast Reviewed:10/7/2005
Keywords:kbBug kbfix kbQFE KB238621