IT24015: MQCONN from application returns MQRC_ALREADY_CONNECTED when hConn is invalid

APAR status

• Closed as program error.

Error description

• If MQCONN or MQCONNX is called with an invalid connection handle
  (hConn) then
  MQCONN might incorrectly return MQRC_ALREADY_CONNECTED
  (rc=2002) and the following FDC might be generated.
  
  An FDC might be generated with the following symptoms.
  Probe Id          :- ZS051010
  Major Errorcode   :- MQRC_HCONN_ERROR
  Probe Description :- AMQ6125: An internal IBM MQ error has
  occurred.
  MQM Function Stack
  MQCONNX
  zswGetEntryPointsByName
  MQCONNX
  xcsFFST
  

Local fix

• n/a
  

Problem summary

• ****************************************************************
  USERS AFFECTED:
  Users of IBM MQ who supply an invalid hConn on an MQCONN or
  MQCONNX call.
  
  
  Platforms affected:
  MultiPlatform
  
  ****************************************************************
  PROBLEM DESCRIPTION:
  A logic error in the validation routines when accepting the
  connection caused the MQRC_ALREADY_CONNECTED (2002) return code
  to be returned in a case where MQRC_HCONN_ERROR (2018) was the
  correct response.
  
  A code path also existed whereby MQRC_ALREADY_CONNECTED (2002)
  could be returned in response to a damaged in-memory data
  structure representing the connection. In this case, the
  expected return code is MQRC_UNEXPECTED_ERROR (2195), as such
  damage should not occur under normal operation.
  

Problem conclusion

• The MQ queue manager logic has been updated to correctly return
   MQRC_HCONN_ERROR (2018) or MQRC_UNEXPECTED_ERROR (2195) as
  appropriate in these scenarios.
  
  ---------------------------------------------------------------
  The fix is targeted for delivery in the following PTFs:
  
  Version    Maintenance Level
  v9.1 CD    9.1.2
  v9.1 LTS   9.1.0.2
  
  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

  IBM MQ BASE M/P

• Fixed component ID

  5724H7261

Applicable component levels

• R903 PSY

     UP