IT30342: MEMORY BLOCK HEADER CORRUPTION MAY OCCUR WHEN A SELECT CURSOR ISRE-OPENED

APAR status

• Closed as program error.

Error description

• An assert failure may occur when the cursor for a select
  statement using one or more sub-queries is re-opened a number of
  times. An example of the type of AF that may occur:
  
  Bad block header 0x700000021ae7ea8
  Assert Warning: Memory block header corruption detected in
  mt_shm_free 1
  IBM Informix Dynamic Server Version 12.10.FC13
   Who: Session(9, informix@idsserver.com, -1,
  700000020513048)
        Thread(57, sqlexec, 7000000204d1368, 1)
        File: mtshpool.c Line: 2767
   Results: Pool repaired
   Action: Please notify IBM Informix Technical Support.
  
  (oninit)afhandler
  (oninit)afwarn_interface
  (oninit)mt_free
  (oninit)fm_vti_freefrag
  (oninit)fm_closefrags@AF25_13
  (oninit)fm_closefrags
  (oninit)fmclose
  (oninit)sqisclose
  (oninit)closerel
  (oninit)scan_free
  (oninit)join_free
  (oninit)join_free
  (oninit)sort_free
  (oninit)closecb
  (oninit)close_cb_subtree_r
  (oninit)close_cb_subtree
  (oninit)closesdb
  (oninit)close_cursor
  (oninit)sql_close
  (oninit)sq_close
  (oninit)sqmain
  
  This example is from the server running on AIX. The stack for
  other OS platforms may be slightly different. Depending on how
  the memory is corrupted other types of AF are also possible,
  such as a crash caused by attempting to access invalid memory.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED:                                              *
  * Users of Informix Server prior to 12.10.xC14 and 14.10.xC3.  *
  ****************************************************************
  * PROBLEM DESCRIPTION:                                         *
  * See Error Description                                        *
  ****************************************************************
  * RECOMMENDATION:                                              *
  * Update to Informix Server 12.10.xC14 or 14.10.xC3.           *
  ****************************************************************
  

Problem conclusion

• Fixed in Informix Server 12.10.xC14 and 14.10.xC3.
  

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

  INFORMIX SERVER

• Fixed component ID

  5725A3900

Applicable component levels