Q161774: Snalink.exe (SNADLC/802.2) Access Violation in Sbpa4snd()

Article: Q161774
Product(s): Microsoft SNA Server
Version(s): WINDOWS:2.0,2.1,2.11
Operating System(s): 
Keyword(s): 
Last Modified: 12-JUN-2001

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The information in this article applies to:

- Microsoft SNA Server, versions 2.0, 2.1, 2.11 
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SYMPTOMS
========

In very rare conditions, the SNA Server 802.2 link service (supporting an SNA
connection over Token Ring, Ethernet, or FDDI) may encounter an access violation
(AV) leading to the following errors:

- Users lose their sessions over any SNA Server connection using this link
  service.

- The following Windows NT application event log error occurs:

  Event ID: 624
  Source: SNADLC1
  Creating dump file C:\SNA\traces\snadump.log for SNALINK.EXE

- A Drwtsn32.log entry is created that indicates an application exception error
  occurred in Snalink.dbg:

     Application exception occurred:
           App: snalink.DBG (pid=<process id>)
           Exception number: c0000005 (access violation)

     State Dump for Thread Id <thread>

     eax=0019000a ebx=00620c00 ecx=00000381 edx=00000103 esi=00620d6a
     edi=012202b5
     eip=003d96c7 esp=003cfeac ebp=01025f28 iopl=0         nv up ei pl nz
     na po nc
     cs=001b  ss=0023  ds=0023  es=0023  fs=0038  gs=0000
     efl=00000206

     function: sbpa4snd
     [...]

         003d96c4 8b6d00       mov   ebp,[ebp]
  ss:0170484a=????????
     FAULT ->003d96c7 66894504     mov   [ebp+0x4],ax
  ss:0170484b=????

CAUSE
=====

An access violation may occur if the Snadlc.dll link service formats data to
pass to the SNA Server service while Dlc.sys passes up empty buffers with the
total data length of a certain size. This is a rare condition that has only been
observed at one customer site.

RESOLUTION
==========

A fix is available to correct this problem.


STATUS
======

Microsoft has confirmed this to be a problem in SNA Server versions 2.0, 2.1,
and 2.11.


A supported fix is now available, but has not been fully regression-tested and
should be applied only to systems experiencing this specific problem. Unless you
are severely impacted by this specific problem, Microsoft recommends that you
wait for the next Service Pack that contains this fix. Contact Microsoft
Technical Support for more information.



Additional query words: prodsna 2.00 2.10 2.11

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Keywords          :  
Technology        : kbAudDeveloper kbSNAServSearch kbSNAServ200 kbSNAServ211 kbSNAServ210
Version           : WINDOWS:2.0,2.1,2.11
Issue type        : kbbug
Solution Type     : kbfix

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