DOCUMENT:Q172606  02-APR-2000  [sna]
TITLE   :SNA Server Access Violation When Receiving Invalid XID Frames
PRODUCT :Microsoft SNA Server
PROD/VER:WINDOWS:3.0,3.0 SP1
OPER/SYS:
KEYWORDS:kbnetwork

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The information in this article applies to:

 - Microsoft SNA Server, versions 3.0, 3.0 SP1 
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SYMPTOMS
========

SNA Server may encounter access violations or hard-coded break points within
Snaservr.exe in an environment where corrupt 802.2 frames are being sent as a
result of a bad network card or network card driver. The failures result in a
Drwtsn32.log that may show the following type of failures:

   Application exception occurred:
   App: snalink.DBG (pid=216)
   When: 7/22/1997 @ 13:53:4.828
   Exception number: 80000003 (hardcoded breakpoint)

In the Windows NT Application log the following event will be logged with the
same timestamp as the hard-coded break point:

   

   Event ID : 686
   Source: DLC Link Service
   Time:14:53:4
   Type: Error
   Category: None
   Description: SNA Server Internal buffer pool error.
      Reason  = Invalid Owner Id
      Module  = D:\sna\system\SNALINK.EXE
      Process = 216
      Pool    = TRUSTED ELTS
      Details = Current Owner Id D8H, Correct ID 1BF801EEH
      EXPLANATION - While processing a buffer pool request, it was noticed
      that the buffer pool had been corrupted.

SNA traces of the failures may show corrupted XID frames or terminate during the
processing of an XID.

CAUSE
=====

If an XID is received with an incorrect length field, the SNA Server XID parsing
code fails to handle the processing of the frame correctly.

Please refer to the IBM SNA Formats Guide (GA27-3136) for more information on XID
formats.

STATUS
======

Microsoft has confirmed this to be a problem in SNA Server versions 3.0 and 3.0
Service Pack 1 (SP1). 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 applied, the XID parsing behavior of SNA Server correctly handles
XIDs with invalid length fields.


Additional query words: EventID 686 Hardcoded

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Keywords          : kbnetwork 
Technology        : kbAudDeveloper kbSNAServSearch kbSNAServ300 kbSNAServ300SP1
Version           : WINDOWS:3.0,3.0 SP1
Issue type        : kbbug
Solution Type     : kbfix

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