DOCUMENT:Q169488 13-JUN-2001 [sna] TITLE :Errors When Performance Monitoring SNA Server PRODUCT :Microsoft SNA Server PROD/VER:WINDOWS:3.0,3.0 SP1 OPER/SYS: KEYWORDS:kbnetwork ====================================================================== ------------------------------------------------------------------------------- The information in this article applies to: - Microsoft SNA Server, versions 3.0, 3.0 SP1 ------------------------------------------------------------------------------- SYMPTOMS ======== When you initially activate Windows NT Server Performance Monitor to collect SNA Server performance data, the following errors may occur: - Perfmon.exe may encounter an access violation. - If SNA Server is running on Windows NT Server 3.51, a Winlogon.exe access violation may occur, leading to a STOP 0x0000001E error. - If SNA Server is running on Windows NT Server 4.0, the following event may be logged in the Windows NT application event log: Event ID: 1013 Source: Perflib Description: The collect procedure in Extensible Counter DLL "C:\SNA\system\snaperf.dll" for the "SnaServr" service returned a buffer that was larger than the space allocated and may have corrupted the application's heap. This DLL should be disabled or removed from the system until the problem has been corrected to prevent further corruption. The application accessing this performance data should be restarted. The Performance data returned by counter DLL will be not be returned in Perf Data Block. Overflow size is data DWORD 0. - If SNA Server is running on Windows NT 4.0, a winlogon.exe access violation may occur, which would cause the following log entry in the \drwtsn32.log file: Application exception occurred: App: exe\winlogon.dbg () Exception number: c0000005 (access violation) [...] function: RtlAllocateHeap [...] FAULT ->77f64654 0fb716 movzx edx,word ptr [esi] CAUSE ===== The SNA Server performance monitoring collection routine returns a Buffer Size greater than the Perfmon buffer pointer allocated. The data collection routines AddNodeCounters and AddRTMCounters write data to the buffer, but fail to decrement the remaining byte count, which results in the buffer write operation going past the end of the buffer. STATUS ====== Microsoft has confirmed this to be a problem in SNA Server version 3.0 and 3.0 Service Pack 1. This problem was corrected in the latest SNA Server version 3.0 U.S. Service Pack. For information on obtaining this Service Pack, query on the following word in the Microsoft Knowledge Base (without the spaces): S E R V P A C K MORE INFORMATION ================ With the fix, the code has been modified to decrement the remaining byte count for the Node and RTM counter collections. Additional query words: crash blue ====================================================================== Keywords : kbnetwork Technology : kbAudDeveloper kbSNAServSearch kbSNAServ300 kbSNAServ300SP1 Version : WINDOWS:3.0,3.0 SP1 Issue type : kbbug Solution Type : kbfix ============================================================================= THE INFORMATION PROVIDED IN THE MICROSOFT KNOWLEDGE BASE IS PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND. MICROSOFT DISCLAIMS ALL WARRANTIES, EITHER EXPRESS OR IMPLIED, INCLUDING THE WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE. IN NO EVENT SHALL MICROSOFT CORPORATION OR ITS SUPPLIERS BE LIABLE FOR ANY DAMAGES WHATSOEVER INCLUDING DIRECT, INDIRECT, INCIDENTAL, CONSEQUENTIAL, LOSS OF BUSINESS PROFITS OR SPECIAL DAMAGES, EVEN IF MICROSOFT CORPORATION OR ITS SUPPLIERS HAVE BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES SO THE FOREGOING LIMITATION MAY NOT APPLY. Copyright Microsoft Corporation 2001.