IT37357: IBM MQ ON AIX WRITES KRCE_UNEXPECTED_ERROR AND LRCE_SECURITY_ERROR FDCS WHEN THE USERNAME IS LONGER THAN THE SYSTEM'S ALLOWED MA

APAR status

• Closed as program error.

Error description

• When MQ calls the AIX C library function getuserattr() to find
  the list of groups for a given user, one of the first things
  getuserattr() does is check the username is not longer than the
  maximum allowed by the operating system. If it is too long, AIX
  returns failure with errno=EINVAL.
  
  In this situation, MQ would then write out an FDC record:
  
  Probe Id :- ZF226020
  Component :- zfuGetGroupsUsingGetuserattr
  Major Errorcode   :- krcE_UNEXPECTED_ERROR
  
  There is no need for this FDC in this specific case because
  there is no real defect within MQ code.
  

Local fix

Problem summary

• ****************************************************************
  USERS AFFECTED:
  Users of MQ on AIX, where usernames exist on the OS that have
  names longer than the currently-configured OS limit, and such a
  user runs an MQ application program.  This situation is most
  likely to arise if the user was created when the OS limit was
  higher, then the OS limit was lowered.
  
  
  Platforms affected:
  AIX
  
  ****************************************************************
  PROBLEM DESCRIPTION:
  The ZF226020 FDC was being written because the OS getuserattr()
  function call had failed with errno=EINVAL.  But there was no
  need for an FDC in this specific case.
  

Problem conclusion

• Some code has been added for this case, to check the OS limit on
  the username length.  If the username is too long, MQ avoids
  writing the FDC, because it would not be helpful.  The overall
  operation still correctly fails with appropriate return codes
  and error messages, but without an FDC being written.
  
  Note that if getuserattr() fails with errno=EINVAL, but the
  username is not too long, then the FDC will still correctly be
  written.
  
  ---------------------------------------------------------------
  The fix is targeted for delivery in the following PTFs:
  
  Version    Maintenance Level
  v8.0       8.0.0.17
  v9.0 LTS   9.0.0.12
  v9.1 LTS   9.1.0.10
  v9.2 LTS   9.2.0.4
  v9.x CD    9.2.4
  
  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 MP

• Fixed component ID

  5724H7251

Applicable component levels