PI22642: DFHSM0002 CODE X'0317' FREEMAIN_LENGTH_OVERLAYS_NEXT_SCF REMARK(XMATCTXT)

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• You are receiving DFHSM0002 code X'0317' when a CICS
  Application on one system has made a remote DL/I request.
  This has caused a CSM5 mirror transaction to be attached
  in the remote (DL/I owning) system. Application Context
  Data appears to have flown over to the remote system. We
  GETMAINED some storage to hold that and pass it to CSM5.
  .
  The trace shows the following exception trace entry when
  tran ID CSM5 is doing FREEMAIN,
  QR    SM 0317 SMGF  *EXC* Freemain_length_overlays_next_SCF
                            FUNCTION(FREEMAIN)
                            SUBPOOL_TOKEN(22C8474C , 0000000A)
                            ADDRESS(22D07C10)
                            FREE_LENGTH(DC)
                            REMARK(XMATCTXT)
  .
  Furthermore, found the issue is
  DFHZATT thinks it has found some incoming Application
  Context Data, even though it is beyond the real length of
  the data. It is doing a GETMAIN based on the length included
  with this data, and passing the area to CSM5. Later, CSM5
  attempts to freemain this based on the real length of
  Application Context data. The lengths on the GETMAIN and
  FREEMAIN do not match that leads to this error.
  .
  Additional Symptom(s) Search Keyword(s): KIXREVRJS
  DFHSM0102 Storage violation occurs due to trailing SAA
  altered - value of x'96' changed to x'97'
  SM 0D05 SMMF  *EXC* - SAA_check_failed_on_TP_freemain
  FUNCTION FREEMAIN TERMINAL STORAGE TIOA Leading
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: All CICS users.                              *
  ****************************************************************
  * PROBLEM DESCRIPTION: Data which is not contained within an   *
  *                      incoming attach request in the TIOA can *
  *                      be interpreted as initial application   *
  *                      context and current application context *
  *                      subfields and passed on transaction     *
  *                      attach.                                 *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  DFHZATT parses an incoming transaction attach request in a TIOA
  owned by an MRO session. Code in DFHZATT looks for an FMH43 and
  starts looking for a X'95' value in field FMHCARGN which
  signifies the presence of ACD application context data in the
  TIOA. However, the code fails to test if it has reached the end
  of the request before checking for a X'95' value.
  It encounters a X'95' which is part of residual data from a
  previous request processed using the same TIOA. DFHZATT
  references this residual data as context data when it issues the
  DFHXMAT ATTACH, but there is no context data in this case and
  the data passed to transaction manager is invalid. A similar
  problem can occur for current application context CAC data,
  identified by an X'96' value in field FMHCARGN.
  
  Additional keywords: INITIAL_APPLICATION_CONTEXT
                       CURRENT_APPLICATION_CONTEXT
                       0C4 S0C4 abendS0C4
  

Problem conclusion

• DFHZATT has been changed to ensure that application context data
  fits within the request held in the TIOA before passing this as
  context data to transaction manager.
  A similar change has been made for current application context
  data.
  

Temporary fix

• FIX AVAILABLE BY PTF ONLY
  

Comments

APAR Information

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

  PI20943

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

  UI25834

Modules/Macros

• DFHZATT
  

Fix information

• Fixed component name

  CICS TS Z/OS V5

• Fixed component ID

  5655Y0400

Applicable component levels

• R900 PSY UI25834

     UP15/03/20 P F503

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.