PI45592: IMS CONNECT ADDRESS SPACE FILLS WITH SVT CONTROL BLOCKS.

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• The customer IMS Connect User message exit returned OTMA State
  Data headers with a length of x'004C'.  IMS Connect stored this
  in the socket control block (SVT).  However the SVT only allows
  for a maximum of x'48' bytes.  Then after that there are 256
  bytes for the OTMA User Data.  When IMS Connect moved x'4C'
  bytes of State Data and then x'100' bytes of OTMA user data it
  overlayed the first four bytes of the CBT buffer holding the
  SVT.  These 4 bytes have an eyecatcher that BPE uses to verify
  that it is deleting a valid block.  This eyecatcher is now
  x'00000000' and BPE thinks the block is invalid and does not
  delete the control block when requested.  The OTMA State data
  should not be modified by the customer, but it also should not
  cause IMS Connect to fill up storage.
  

Local fix

• The customer should not modify the OTMA State Data.  The
  customer should add their data in the OTMA User Data Prefix
  starting at offset x'100'.
  

Problem summary

• ****************************************************************
  * USERS AFFECTED:                                              *
  * All IMS V14 users of IMS Connect that                        *
  * increase the size of the State Data section                  *
  * of the OTMA headers, HWSOMHDR, defined in                    *
  * the HWSOMPFX macro.                                          *
  ****************************************************************
  * PROBLEM DESCRIPTION:                                         *
  * IMS Connect?s address space fills up                         *
  * with SVT control blocks.                                     *
  *                                                              *
  * Forward-fit of APAR PI36433.                                 *
  ****************************************************************
  * RECOMMENDATION:                                              *
  * INSTALL CORRECTIVE SERVICE FOR APAR/PTF                      *
  ****************************************************************
  IMS Connect?s SVT blocks have a fixed amount of storage to save
  portions of the OTMA headers defined in macro HWSOMPFX. The
  information saved in the SVT control block is used to build a
  response message in case of an error such as a timeout.
  The amount of storage reserved for the State Data portion of
  the OTMA header is 72 bytes. The current logic in IMS Connect
  does not honor that fixed size when saving the State Data
  portion of the OTMA headers in the SVT. Increasing the size of
  the State Data to a value larger than 72 bytes could cause an
  overlay of an internal identifier of the SVT control block and
  IMS Connect is not able to release the SVT block when it is no
  longer needed. Thus, the IMS Connect address space starts to
  fill up with SVT control blocks.
  

Problem conclusion

• IMS Connect will only save up to the first 72 bytes of the
  State Data portion of the OTMA headers. This behavior is
  similar to what IMS Connect does when saving the User Data
  portion of the OTMA headers, which is limited to the first
  256 bytes.
  
  HWSSREC0 has been enhanced to only save up to 72 bytes of
           State Data.
  

Temporary fix

Comments

APAR Information

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

  PI36433

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

  UI30141

Modules/Macros

• HWSSREC0
  

Fix information

• Fixed component name

  IMS V14

• Fixed component ID

  5635A0500

Applicable component levels

• R400 PSY UI30141

     UP15/08/18 P F508

Fix is available

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