IT42975: Possibility of memory exception in IBM MQ diagnostic routine

APAR status

• Closed as program error.

Error description

• IBM has identified the possibility of a diagnostic routine
  (xfdDumpProcDirCB) making an invalid memory access, which could
  trigger a SIGSEGV.
  
  This issue has not been observed under real-world conditions.
  

Local fix

Problem summary

• ****************************************************************
  USERS AFFECTED:
  Users of IBM MQ on Unix or Linux
  
  
  Platforms affected:
  IBM iSeries, Linux on Power, Linux on x86-64, Linux on zSeries,
  AIX
  
  ****************************************************************
  PROBLEM DESCRIPTION:
  A logic error was identified within an MQ diagnostic function
  (xfdDumpProcDirCB), called when generating a failure data
  capture (FDC) file. If this routine were to receive an
  unexpected error code from an operating system "stat" call, the
  error handling could attempt to dereference an uninitialized
  variable.
  

Problem conclusion

• The xfdDumpProcDirCB function has been corrected to avoid
  accessing the uninitialized variable in the event that "stat"
  returns an unexpected error code.
  
  ---------------------------------------------------------------
  The fix is targeted for delivery in the following PTFs:
  
  Version    Maintenance Level
  v9.3 LTS   9.3.0.20
  v9.4 LTS   9.3.3
  
  The latest available maintenance can be obtained from
  'IBM MQ Recommended Fixes'
  https://www.ibm.com/support/pages/recommended-fixes-ibm-mq
  
  If the maintenance level is not yet available information on
  its planned availability can be found in 'IBM MQ
  Planned Maintenance Release Dates'
  https://ibm.biz/mqplannedmaintenance
  
  ---------------------------------------------------------------
  

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 V9.3

• Fixed component ID

  5724H7291

Applicable component levels