PM75165: STORAGE OVERLAY WITH THE STRING '3FDA4'X 0C4 DSNXODMH +243E and LOOP in DSNXADMH due to overlay in DMHE

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• Storage overlaid with the string '3FDA4'x.
  Also seen
  0C4 DSNXODMH +243E and LOOP in DSNXADMH due to overlay in DMHE
  

Local fix

• N/A
  

Problem summary

• ****************************************************************
  * USERS AFFECTED: All DB2 9 and 10 users.                      *
  ****************************************************************
  * PROBLEM DESCRIPTION: Storage overlaid with the string        *
  *                      '3FDA4'x.  This can result in ABENDs    *
  *                      such as                                 *
  *                                                              *
  *                      ABEND0C4 RC38 AT DSNSCON2 OFFSET 1608   *
  *                                                              *
  *                      Other ABEND symptoms possible           *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  When a remote statement encounters an SQL condition, the SQL
  connection information (of the condition) is appended to the
  diagnostics block at the requester. Normally, only the
  connection from the previous statement is saved, but in the
  error case, the connections accumulated in the diagnostics
  block across statements.
  
  This eventually caused an internal field to wrap and become
  negative, which in turn lead to a storage overlay that resulted
  in an ABEND.
  
  
  Example:
  
  <statements executed at LOCATION1>
  
  CONNECT TO LOCATION2;
  
  SELECT * FROM LOCATION1.USER01.TABLE01;   SELECT1
  
  SELECT * FROM LOCATION1.USER01.TABLE01;   SELECT2
  
  In the example above,  SELECT1  encounters SQLCODE -204,
  and the connection (LOCATION2) is appended to LOCATION1's
  diagnostics block.
  
  However, the LOCATION1 connection from  SELECT1  is preserved
  when  SELECT2  again encounters SQLCODE -204, and the internal
  field recording the number of connections recorded thus far is
  incremented to 2.
  
  When a large number of such statements are executed in
  succession, the internal counter continues to be incremented and
  eventually wraps to become negative, leading to a storage
  overlay.
  

Problem conclusion

• DB2 code has been corrected to no longer preserve the
  SQL connections in the diagnostics block across SQL statements
  at the requester site.  The internal field in question will
  therefore not become negative due to wrapping.
  
  ADDITIONAL KEYWORDS: SMCOVERLAY DB2OVRLAY/K
  

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:

  UK90699 UK90700

Modules/Macros

• DSNLZRCD DSNXEADW
  

Fix information

• Fixed component name

  DB2 OS/390 & Z/

• Fixed component ID

  5740XYR00

Applicable component levels

• RA10 PSY UK90699

     UP13/01/17 P F301

• R910 PSY UK90700

     UP13/01/17 P F301

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.