FIX: SQL Trace May Cause Heap Corruption After Handled Exception

ID: Q238970

The information in this article applies to:

Microsoft SQL Server version 6.5

BUG #: 18753 (SQLBUG_65)

SYMPTOMS

After experiencing a handled exception within SQL Server, if SQL Trace was in use and monitoring disconnect events at the time of the exception, SQL Server may generate further exceptions when allocating or freeing memory. The stack trace might include functions such as ntdll!RtlAllocateHeapSlowly, ntdll!RtlFreeHeap, or ntdll!RtlpCoalesceFreeBlocks. The server hangs after several such exceptions. When running under a debugger, a heap manager message is printed after SQL Server finishes handling the exception. For example, a heap message might be:

HEAP[sqlservr.exe]: Invalid Address specified to RtlFreeHeap( 140000, 14b1e0 )

RESOLUTION

A supported fix that corrects this problem is now available from Microsoft, but it has not been fully regression tested and should be applied only to systems experiencing this specific problem. If you are not severely affected by this specific problem, Microsoft recommends that you wait for the next SQL Server service pack that contains this fix.

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 on support costs, please go to the following address on the World Wide Web:

http://www.microsoft.com/support/supportnet/overview/overview.asp

The English version of this fix should have the following file attributes or later:


   File name     Platform
   ----------------------

   sql453i.exe   x86
   sql453a.exe   Alpha

NOTE: Due to file dependencies, the most recent hotfix or feature that contains the above files may also contain additional files.

STATUS

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

MORE INFORMATION

Additional query words:

Keywords : SSrvAdmin SSrvErr_Log SSrvGPF kbbug6.50 kbSQLServ650bug
Version : winnt:6.5
Platform : winnt
Issue type : kbbug