IC66174: WMQ V7.0 CLIENT CONVERSATION SHARING MEMORY ACCESS VIOLATION UNDER RESOURCE CONSTRAINT CONDITIONS

WebSphere MQ V7.0.1 for i5/OS Fix Pack 7.0.1.3
WebSphere MQ V7.0 Fix Pack 7.0.1.3

APAR status

• Closed as program error.

Error description

• A client application using conversation sharing failed during
  the MQ connect call due to an error when starting a thread.
  Afterwards, the client application ended abruptly with a memory
  access violation.
  
  A xecP_E_NO_RESOURCE FFST was produced by xcsCreateThread,
  accompanied by the following additional FFST:
  
  Operating System  :- Windows Server 2003, Build 3790: SP2
  LVLS              :- 7.0.1.0
  Product Long Name :- WebSphere MQ for Windows
  Probe Id          :- XC130031
  Application Name  :- MQM
  Component         :- xehExceptionHandler
  Addressing mode   :- 32-bit
  Process           :- 00009264
  Major Errorcode   :- xecF_E_UNEXPECTED_SYSTEM_RC
  Minor Errorcode   :- OK
  Probe Type        :- MSGAMQ6119
  Probe Severity    :- 2
  Probe Description :- AMQ6109: An internal WebSphere MQ error has
  occurred.
  FDCSequenceNumber :- 1
  Comment1          :- Access Violation at address 00000590 when
  reading
  .
  MQM Function Stack
  ImqQueueManager::connect
  MQCONNX
  trmzstMQCONNX
  reqDoConnect
  reqConnectChl
  reqFreeSess
  rriFreeSess
  ccxFreeSocket
  xcsFFST
  
  FDC Trace History Snippet:
  ---} xcsFFST rc=OK
  --} xcsCreateThread rc=xecP_E_NO_RESOURCE
  --{ cccFreeMem
  ---{ xcsFreeMemFn
  ---} xcsFreeMemFn rc=OK
  --} cccFreeMem rc=OK
  --{ rrxError
  --} rrxError rc=rrcE_CREATE_THREAD_ERROR
  -} ccxSetAsyncMode rc=rrcE_CREATE_THREAD_ERROR
  -{ ccxFreeMem
  --{ ccxPoolFree
  ---{ xcsRequestThreadMutexSem
  ---} xcsRequestThreadMutexSem rc=OK
  ---{ xcsReleaseThreadMutexSem
  ---} xcsReleaseThreadMutexSem rc=OK
  --} ccxPoolFree rc=OK
  -} ccxFreeMem rc=OK
  } rriInitSess rc=rrcE_CREATE_THREAD_ERROR
  { rrxError
  } rrxError rc=rrcE_CREATE_THREAD_ERROR
  { rrxReportError
  -{ xcsDisplayMessageForSubpool
  --{ xcsQueryDateTime2
  --} xcsQueryDateTime2 rc=OK
  --{ xcsGetEnvironmentString
  --} xcsGetEnvironmentString rc=xecE_E_ENV_VAR_NOT_FOUND
  --{ xcsGetEnvironmentInteger
  ---{ xcsGetEnvironmentString
  ---} xcsGetEnvironmentString rc=xecE_E_ENV_VAR_NOT_FOUND
  --} xcsGetEnvironmentInteger rc=xecE_E_ENV_VAR_NOT_FOUND
  --{ xcsQueryValueForSubpool
  --} xcsQueryValueForSubpool rc=OK
  --{ xcsDisplayMessage
  ---{ xcsGetMemFn
  ---} xcsGetMemFn rc=OK
  ---{ xcsGetMessage
  ----{ xcsGetMemFn
  ----} xcsGetMemFn rc=OK
  ----{ xeeConvertInserts
  -----{ xcsGetMemFn
  -----} xcsGetMemFn rc=OK
  ----} xeeConvertInserts rc=OK
  ----{ xgmNTGetMessage
  -----{ xgmCheckMsgSource
  -----} xgmCheckMsgSource rc=OK
  -----{ xgmDetermineMsgCatLanguage
  ------{ xcsGetEnvironmentString
  ------} xcsGetEnvironmentString rc=xecE_E_ENV_VAR_NOT_FOUND
  ------{ xgmValidLanguage
  ------} xgmValidLanguage rc=OK
  -----} xgmDetermineMsgCatLanguage rc=OK
  ----} xgmNTGetMessage rc=OK
  ----{ xcsFreeMemFn
  ----} xcsFreeMemFn rc=OK
  ----{ xcsFreeMemFn
  ----} xcsFreeMemFn rc=OK
  ---} xcsGetMessage rc=OK
  ---{ xcsIsEnvironment
  ---} xcsIsEnvironment rc=OK
  ---{ xeeOpenFiles
  ---} xeeOpenFiles rc=OK
  ---{ xeeCloseFiles
  ---} xeeCloseFiles rc=OK
  ---{ xgmWriteNTEventLog
  ----{ xgmCheckMsgRequired
  ----} xgmCheckMsgRequired rc=OK
  ----{ xgmCheckMsgSource
  ----} xgmCheckMsgSource rc=OK
  ----{ xeeConvertInserts
  -----{ xcsGetMemFn
  -----} xcsGetMemFn rc=OK
  ----} xeeConvertInserts rc=OK
  ----{ xcsFreeMemFn
  ----} xcsFreeMemFn rc=OK
  ---} xgmWriteNTEventLog rc=OK
  ---{ xcsFreeMemFn
  ---} xcsFreeMemFn rc=OK
  --} xcsDisplayMessage rc=OK
  -} xcsDisplayMessageForSubpool rc=OK
  } rrxReportError rc=OK
  { reqFreeSess
  -{ rriFreeSess
  --{ ccxAllocMem
  ---{ cciAllocMem
  ----{ cccGetMem
  -----{ xcsGetMemFn
  -----} xcsGetMemFn rc=OK
  ----} cccGetMem rc=OK
  ---} cciAllocMem rc=OK
  --} ccxAllocMem rc=OK
  --{ ccxSend
  ---{ cciTcpSend
  ----{ send
  ----} send rc=OK
  Data: 0x0000001c
  ---} cciTcpSend rc=OK
  --} ccxSend rc=OK
  --{ ccxFreeMem
  --} ccxFreeMem rc=OK
  --{ ccxFreeSocket
  ---{ xcsRequestThreadMutexSem
  ---} xcsRequestThreadMutexSem rc=OK
  ---{ xcsCheckPointer
  ---} xcsCheckPointer rc=OK
  ---{ xcsReleaseThreadMutexSem
  ---} xcsReleaseThreadMutexSem rc=OK
  ---{ cciTcpFreeConv
  ----{ ioctl
  ----} ioctl rc=OK
  ----{ soclose
  ----} soclose rc=OK
  ---} cciTcpFreeConv rc=OK
  ---{ xcsFFST
  .
  --->------------------------------<DUMP
  END>------------------------------<---
  As a result of a Severe Abend Error, a MiniDump has been written
  to: AMQ9264.6468.0.dmp
  An Unhandled Exception detected in process 9264, on thread
  0x1944.
  Type: EXCEPTION_ACCESS_VIOLATION (C0000005).
  Address: 001B:4E373B76.
  The thread could not read from memory address 0x00000590
  
  This will be accompanied by error message AMQ9233 (error
  creating receive thread) in the machine-wide WebSphere MQ error
  logs.
  
  The same failure can also occur on UNIX systems, where it will
  cause a SIGSEGV FFST with probe XC130003.
  

Local fix

Problem summary

• ****************************************************************
  USERS AFFECTED:
  Users of WebSphere MQ 7 clients who use conversation sharing.
  The failure will occur when a resource constraint prevents the
  creation of new threads.
  
  Platforms affected:
  All Distributed (iSeries, all Unix and Windows)
  ****************************************************************
  PROBLEM SUMMARY:
  When starting a new client connection when conversation sharing
  is enabled, WebSphere MQ starts a new thread to handle socket
  receives for all conversations sharing the socket.
  
  If the receive thread could not be started, the WebSphere MQ
  code did not correctly free the connection state data. Whilst
  attempting to close the failed connection, MQ attempted to wait
  for the receive thread which had never started. This
  dereferenced an invalid pointer, which caused a memory access
  violation.
  

Problem conclusion

• The WebSphere MQ code has been modified to correctly handle
  cleanup of failed connections after a failure to start the
  receive thread.
  
  ---------------------------------------------------------------
  The fix is targeted for delivery in the following PTFs:
  
                     v7.0
  Platform           Fix Pack 7.0.1.3
  --------           --------------------
  Windows            tbc_p700_0_1_3
  AIX                tbc_p700_0_1_3
  HP-UX (PA-RISC)    tbc_p700_0_1_3
  HP-UX (Itanium)    tbc_p700_0_1_3
  Solaris (SPARC)    tbc_p700_0_1_3
  Solaris (x86-64)   tbc_p700_0_1_3
  iSeries            tbc_p700_0_1_3
  Linux (x86)        tbc_p700_0_1_3
  Linux (x86-64)     tbc_p700_0_1_3
  Linux (zSeries)    tbc_p700_0_1_3
  Linux (Power)      tbc_p700_0_1_3
  
  The latest available maintenance can be obtained from
  'WebSphere MQ Recommended Fixes'
  http://www-1.ibm.com/support/docview.wss?rs=171&uid=swg27006037
  
  If the maintenance level is not yet available, information on
  its planned availability can be found in 'WebSphere MQ
  Planned Maintenance Release Dates'
  http://www-1.ibm.com/support/docview.wss?rs=171&uid=swg27006309
  ---------------------------------------------------------------
  

Temporary fix

Comments

APAR Information

• APAR is sysrouted FROM one or more of the following:

• APAR is sysrouted TO one or more of the following:

Fix information

• Fixed component name

  WMQ WINDOWS V7

• Fixed component ID

  5724H7220

Applicable component levels

• R700 PSY

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