PM79220: B+TREE ERRONEOUSLY AVAILABLE ADDRESSES

APAR status

• Closed as program error.

Error description

• See Problem Summary.
  

Local fix

• na
  

Problem summary

• APAR NUMBER:  PM79220
  PRODUCT:  z/TPFDF
  FUNCTIONAL AREA:  TPFDF CENTRAL DATABASE ROUTINES
  SHIPPED IN PUT:  10
  
  ABSTRACT:
  With APAR PM38645 applied, issuing a DBDEL or dfdel() API on a
  file that uses 8-byte file address headers and a B+Tree index
  can leave references to released file addresses, resulting in
  erroneously available file addresses.
  
  PACKAGE CONTENTS:
  Source Segments:
  (C) tpfdf/rt/uft6.cpp
  (C) tpfdf/rt/uftb.cpp
  
  Object Only Binaries:
  None.
  
  Configuration Independent Binaries:
  None.
  
  Support Files:
  None.
  
  OTHER BINARIES TO BUILD: YES
  (C) <sys>/load/UFTH.so
  (C) <sys>/obj/uft6.o
  (C) <sys>/obj/uftb.o
  
  COMMENTS:
  A DBDEL macro or dfdel() function call can leave references to
  released file addresses if all of the following are true:
  
   * The file is defined with an 8-byte file address header, and
   * The file has a B+Tree index associated with it, and
   * A DBDEL is issued with the ALL option, or dfdel() is issued
  with the DFDEL_ALL option, and
   * Keys are active, and
   * The result of the API is that all LRECs are deleted from the
  subfile.
  
  In this case, the z/TPFDF B+Tree routines attempt to clear the
  root node reference from the prime data block. However, the
  variable that points to the header is a 4-byte file address
  header pointer, so only 4 bytes are cleared at the wrong
  displacement. As a result, the reference to the root node is
  not cleared, and it will reference released pool addresses.
  This can lead to erroneously available addresses being reported
  when recoup is run.
  

Problem conclusion

• SOLUTION:
  Segments uft6.cpp and uftb.cpp have been updated to properly
  clear the B+Tree node reference from the STD8SBA field of the
  prime data block.
  
  COREQS: NO
  None.
  
  MIGRATION CONSIDERATIONS: NO
  None.
  
  BUILD COMMANDS AND INSTRUCTIONS: YES
  #maketpf commands for linux
  maketpf -f UFTH uft6.o uftb.o
  maketpf UFTH link
  
  UPDATED INFORMATION UNITS: NO
  None.
  
  See your IBM representative if you need additional information.
  
  DOWNLOAD INSTRUCTIONS:
  http://www.ibm.com/software/htp/tpf/maint/maintztpf.html
  
  APAR URL:
  http://www.ibm.com/software/htp/tpf/ztpfmaint/put10/PM79220.htm
  

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

  ZTPFDF

• Fixed component ID

  5748F1501

Applicable component levels

• R110 PSY

     UP