IBM Support

IT27842: A STALE SQLCA POINTER FROM SQLZESQLCODE() CORRUPTS THE STACK FRAME LEADING TO AN ENDLESS LOOP

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APAR status

  • Closed as program error.

Error description

  • A stale SQLCA pointer from sqlzeSqlCode() corrupts the return
    pointer in the stack frame leading to an endless loop
    
    Setting up a connection idle threshold with a connect procedure
    is enough to reproduce this scenario.
    Repro steps:
    
    -- Connection IDLE threshold
    CREATE THRESHOLD CONIDLE FOR DATABASE ACTIVITIES ENFORCEMENT
    DATABASE WHEN CONNECTIONIDLETIME > 1 MINUTES STOP EXECUTION
    ALTER THRESHOLD CONIDLE ENABLE
    
    -- Stored procedure
    CREATE PROCEDURE DB2INST1.CNPROC
    language sql
    begin
    IF ( CLIENT_HOST <> 'hostname' )
       THEN
          SIGNAL SQLSTATE '42502' SET MESSAGE_TEXT='Connection
    refused !';--
       END IF;--
    end;
    
    -- DB config for connect_proc
    db2 update db cfg using connect_proc DB2INST1.CNPROC
    
    -- Terminate and reconnect
    

Local fix

Problem summary

  • ****************************************************************
    * USERS AFFECTED:                                              *
    * ALL                                                          *
    ****************************************************************
    * PROBLEM DESCRIPTION:                                         *
    * See Error Description                                        *
    ****************************************************************
    * RECOMMENDATION:                                              *
    * Upgrade to Db2 11.1 Mod 4 Fixpack 5 or higher                *
    ****************************************************************
    

Problem conclusion

  • First fixed in Db2 11.1 Mod 4 Fixpack 5
    

Temporary fix

Comments

APAR Information

  • APAR number

    IT27842

  • Reported component name

    DB2 FOR LUW

  • Reported component ID

    DB2FORLUW

  • Reported release

    B10

  • Status

    CLOSED PER

  • PE

    NoPE

  • HIPER

    NoHIPER

  • Special Attention

    NoSpecatt / Xsystem

  • Submitted date

    2019-01-22

  • Closed date

    2020-01-16

  • Last modified date

    2020-01-16

  • 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

    DB2 FOR LUW

  • Fixed component ID

    DB2FORLUW

Applicable component levels

  • RB10 PSN

       UP

[{"Business Unit":{"code":"BU048","label":"IBM Software"},"Product":{"code":"SSEPGG","label":"DB2 for Linux, UNIX and Windows"},"Component":"","ARM Category":[],"Platform":[{"code":"PF025","label":"Platform Independent"}],"Version":"11.1","Edition":"","Line of Business":{"code":"LOB10","label":"Data and AI"}}]

Document Information

Modified date:
16 January 2020