PI52397: WMQ 7.1: CSQX053E FOR CCXALLOCMEM MAY OCCUR WHEN A LARGE MESSAGE IS GOTTEN BY A CLIENT CHANNEL THAT IS USING SSL/TLS

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• Ø
  A client channel getting large messages with an SSL/TLS client
  sometimes receives reason code 2009 MQRC_CONNECTION_BROKEN. The
  problem occurs when the channel is communicating with a V7.1
  queue manager but not a V8.0 one.
  
  The CHIN joblog has messages
  
   CSQX053E Error information recorded in CSQSNAP data set
   CSQX501I Channel <channel name> no longer active
  
  The eyecatcher of the snap dump looks like
  
  *        X...XFFSccxAllocMem.....*
  *................MOVR......p.....*
  *X...XINS...:....................*
  *................Length..........*
  *................................*
  
  In the reported case, the client was running on a DataPower
  (DP) appliance, but the problem is not limited to DP.
  
  Additional Symptom(s) Search Keyword(s):
  XFFSccxAllocMem 7.1.0 SVRCONN SSL TLS FFST
  CSQX620E System SSL error function 'gsk_secure_socket_read'
           RC=437
  

Local fix

• None unless the channel can temporarily run without SSL/TLS.
  

Problem summary

• ****************************************************************
  * USERS AFFECTED: All users of WebSphere MQ Version 7          *
  *                 Release 1 Modification 0.                    *
  ****************************************************************
  * PROBLEM DESCRIPTION: MQ V7 client application using SSL      *
  *                      SVRCONN channels can receive MQRC 2009  *
  *                      (MQRC_CONNECTION_BROKEN) after MQGET.   *
  *                                                              *
  *                      The CHIN joblog reports error messages  *
  *                      CSQX053E and CSQX620E.                  *
  *                                                              *
  *                      In CSQSNAP dataset, FFST SNAP dumps are *
  *                      generated by function ccxAllocMem.      *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  Distributed MQ V7 clients do not negotiate with the queue
  manager the correct buffer size for SSL during channel
  initiation. This causes MQ V710 for z/OS channel initiator CHIN
  to try to allocate a SSL transmission buffer that is too large
  resulting in ccxAllocMem generating a FFST SNAP dump. The
  current MQGET call or any other active API call terminates with
  MQRC 2009 (MQRC_CONNECTION_BROKEN).
  

Problem conclusion

• MQ V710 for z/OS channel initiator now enforces a maximum SSL
  buffer size avoiding the FFST SNAP dumps, error messages and
  unexpected reason codes on API calls.
  100Y
  CMQXRMSA
  CMQXRSRV
  CSQXCCMX
  CSQXRMSS
  CSQXRMTR
  

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:

  UI34511

Modules/Macros

• CMQXRMSA CMQXRSRV CSQXCCMX CSQXRMSS CSQXRMTR
  

Fix information

• Fixed component name

  WMQ Z/OS V7

• Fixed component ID

  5655R3600

Applicable component levels

• R100 PSY UI34511

     UP16/02/03 P F602

Fix is available

• Select the PTF appropriate for your component level. You will be required to sign in. Distribution on physical media is not available in all countries.