PM06356: EZASMI GETHOSTBYXXXX RESOLVER CONTROL BLOCKS ALLOCATED BELOW THE LINE

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• EZASMI socket applications using resolver functions such as
  GETHOSTBYxxx can experience below the line storage shortages.
  If the the socket application is AMODE31, the 12k resolver
  storage work area should be allocated above the line.
  .
  KEYWORDS:  SUBPOOL 251 Key 8 SP251 k8 AMODE addressing
  mode hostdata hostent 12k 3000 x'3000' GETHOSTBYNAME
  GETHOSTBYADDR RSRV RHST ABEND878 ABEND80A ABEND40D AB878
  AB80A AB40D 878 80A 40D
  

Local fix

• .
  VERIFICATION STEPS:
  -- EZASMI AMODE31 socket application is issuing Resolver
     GETHOSBYNAME calls that are resulting in the allocation
     of 12k of below the line storage.
  -- Output from the IPCS VERBX VSMDATA 'SUMMARY NOG'
     command shows that subpool 251 key 8 storage
     contains allocations of x'3000' that are located
     in below the line storage.
  -- A review of the x'3000' storage area show that they
     contain the following:
  D9E2D9E5   3000FB88   00000000   00000000   | RSRV...
  155EF. LENGTH(X'05E0')--All bytes contain X'00'
  D9C8E2E3   3000FB88   00116E8C   00000000   | RHST...
  1579F. LENGTH(X'01A0')--All bytes contain X'00'
  .....
  

Problem summary

• ****************************************************************
  * USERS AFFECTED: All users of the IBM Communications Server   *
  *                 for z/OS Version 1 Release 11 IP:            *
  *                 Sockets Extended GETHOSTBYNAME/ADDR users    *
  ****************************************************************
  * PROBLEM DESCRIPTION: If a Sockets Extended GETHOSTBYADDR or  *
  *                      GETHOSTBYNAME API call was issued in    *
  *                      AMODE31 the resulting HOSTENT structure *
  *                      was incorrectly located in below the    *
  *                      line storage.                           *
  *                      This could lead to a below the line     *
  *                      storage shortage.                       *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  The Sockets Extended API (EZASMI and EZASOKET) for non-CICS
  applications always allocated the GETHOSTBYADDR/GETHOSTBYNAME
  returned HOSTENT structure to be in below the line storage.
  This could cause the application to experience storage
  shortage errors.
  +-------------------------------------------------------------+
  + Please check our Communications Server for OS/390 homepages +
  + for common networking tips and fixes.  The URL for these    +
  + homepages can be found in Informational APAR II11334.       +
  +-------------------------------------------------------------+
  

Problem conclusion

• The Sockets Extended API is amended to obtain the HOSTENT
  storage based on the AMODE (24 or 31) of the API user.
  
  * Cross Reference between External and Internal Names
  

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:

  UK54396

Modules/Macros

• EZACICA  EZACIC01 EZBSOH03 EZBZMACP
  

Fix information

• Fixed component name

  TCP/IP V3 MVS

• Fixed component ID

  5655HAL00

Applicable component levels

• R1B0 PSY UK54396

     UP10/03/20 P F003

Fix is available

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