PM42667: 0C4 IN DFHXMTA AFTER AN INVALID UOW LENGTH HAS BEEN RECEIVED

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• CICS has received an FMH5 that contains an invalid UOW length.
  The UOW length should have been x'1A' but was x'3A'. Because
  of the incorrect UOW length when CICS analyse the FMH5 it
  also need to save the logical-unit-of-work identifier get
  the wrong displacement and use an incorrect length for the
  LUOW causing the overlay in transaction manager.
  .
  This leads to the INVALID_UOW_IN_ATTACH. This causes a
  FMH5_Error in the INIT_XM_CLIENT function. WHich eventually
  leads to the DFHXM0001 in DFHXMTA which causes the cascade
  of 0C4's to occur.
  .
  KIXREVRJS
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: All CICS Users                               *
  ****************************************************************
  * PROBLEM DESCRIPTION: Message DFHXM0001 An abend (code        *
  *                      0C4/AKEA) has occurred at offset        *
  *                      X'11AE' in module DFHXMTA.              *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  CICS received an FMH5 from TX Series containing a UOW length
  field which was set to a value greater than the maximum
  length of 26.
  During transaction initialisation DFHXMAT uses the UOW passed
  in the FMH5 to create a unique transaction_group_id within
  the xm_txn control block. As part of this processing it stores
  a STCK value in the final 8 bytes of the UOW, however the
  invalid length resulted in corruption of the data following the
  transaction_group_id in the xm_txn block. Later in the
  processing DFHAPXMI is called for RMI_START_OF_TASK. This
  routine loads the TCA address from xm_txm control block but
  this field has been corrupted by the STCK value, resulting in
  an 0C4 when it attempts to use this address.
  Additional keywords: msgDFHXM0001 msgDFHAP0001 DFHAP0001
  DFHZC4935 msgDFHZC4935 INVALID_UOW_IN_ATTACH FMH5_ERROR
  

Problem conclusion

• DFHXMAT has been changed to limit the UOW length to a maximum
  of 26 when using it to create the transaction_group_id.
  

Temporary fix

• FIX AVAILABLE BY PTF ONLY
  

Comments

APAR Information

• APAR is sysrouted FROM one or more of the following:

• APAR is sysrouted TO one or more of the following:

  PM43603 UK70826

Modules/Macros

•    DESXMAT  DFHXMAT  DFHXMTA
  

Fix information

• Fixed component name

  CICS TS Z/OS V4

• Fixed component ID

  5655S9700

Applicable component levels

• R600 PSY UK70826

     UP11/08/17 P F108

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.