IT41354: IBM MQ 9.2 client might report a memory segmentation fault when JSON format CCDT file used along with TLS

APAR status

• Closed as program error.

Error description

• When using a JSON-formatted CCDT file to connect to a queue
  manager using TLS, a SIGSEGV might occur on the IBM MQ Client. A
   client trace shows the following:
  
  FDC:
  LVLS              :- 9.2.0.4
  Product Long Name :- IBM MQ for Linux (x86-64 platform)
  Probe Id          :- XC130003
  Application Name  :- MQM
  Component         :- xehExceptionHandler
  Program Name      :- amqsputc
  Major Errorcode   :- STOP
  Minor Errorcode   :- OK
  Probe Type        :- HALT6109
  Probe Severity    :- 1
  Probe Description :- AMQ6109S: An internal IBM MQ error has
  occurred.
  FDCSequenceNumber :- 0
  Arith1            :- 11 (0xb)
  Comment1          :- SIGSEGV: invalid address
  permissions(0x7f28cc2ee000)
  
  Trace:
  12:29:22.767802    5970.1     RSESS:000001     TS009112314
  pChannels[i].Channel.CD.SSLPeerNameLength=53 Line_number=2552
  12:29:22.767803    5970.1     RSESS:000001     TS009112314
  SSLPEER (len=53)
  12:29:22.767804    5970.1     RSESS:000001       0x0000:
  12345678 12345678 12345678 12345678 |CN=MQMGR123TT,O=|
  12:29:22.767804    5970.1     RSESS:000001       0x0010:
  12345678 12345678 12345678 12345678 |IBM MQ SUPPORT o|
  12:29:22.767804    5970.1     RSESS:000001       0x0020:
  12345678 12345678 12345678 12345678 |f the world,C=us|
  12:29:22.767806    5970.1     RSESS:000001     TS009112314
  ChanDefLength=-2971 line_number=2559
  12:29:22.767807    5970.1     RSESS:000001     TS009112314
  *reclength=2636 line_number=2570
  12:29:22.767983    5970.1     RSESS:000001     Synchronous
  Signal[11] generated in MQ code. Nesting[1] UserCode[0]
  12:29:22.767993    5970.1     RSESS:000001 (05)------{ xcsFFST
  12:29:22.767999    5970.1     RSESS:000001     ErrorCode :-
  40406109 Numeric Insert1 :- b (11) Numeric Insert2 :- 0 (0)
  12:29:22.768001    5970.1     RSESS:000001       String Insert
  :- 'SIGSEGV: address not mapped(0x1c5e000)'
  12:29:22.768005    5970.1     RSESS:000001 (06)-------{
  xcsGetEnvironmentString
  
  Memory allocated for this is a negative number:
  ChanDefLength=-2971. This is not allowed.
  

Local fix

• Use a binary-format CCDT file as an alternative to the affected
  JSON format.
  

Problem summary

• ****************************************************************
  USERS AFFECTED:
  All MQ users who use JSON format CCDT file in combination with
  TLS.
  
  
  Platforms affected:
  MultiPlatform
  
  ****************************************************************
  PROBLEM DESCRIPTION:
  A logic error in the JSON-format CCDT parsing code meant that
  in-memory channel records could be accessed via an invalid
  pointer in TLS was in use.
  

Problem conclusion

• The IBM MQ client code for parsing JSON format CCDT files has
  been corrected to prevent the use of the invalid pointer.
  
  ---------------------------------------------------------------
  The fix is targeted for delivery in the following PTFs:
  
  Version    Maintenance Level
  v9.2 LTS   9.2.0.7
  v9.3 LTS   9.3.0.2
  v9.x CD    9.3.1
  
  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

  MQ BASE V9.2

• Fixed component ID

  5724H7281

Applicable component levels