PQ91666: ABEND0C4 IN EZBIFOUT WITH CLAW DEVICE DEFINED PACKED 04/07/20 PTF PECHANGE

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• When running a CLAW device PACKED an ABEND0C4 occurred in
  EZBIFOUT when a message overran the end of the packing buffer.
  ABEND INFO:  EZBIFOUT(UQ88341 04.132)+002A78 S0C4/00000004
  
  
  VERIFICATION STEPS:
  
  1) Verify CLAW packing is turned on and PQ88146 is installed
  2) ABEND IN EZBIFOUT occurs when packing data into the
     staging buffer on MVC instruction when the "TO" address
     is invalid (may be due to wrong key or storage not available)
  3) Possible for the MVC to complete successfully causing
     an overlay of the storage below the staging buffer.
  
  ADDITIONAL SYMPTOMS:
     ABEND: EZBITSCS(UQ68550 02.212)+000854 S0C4/00000010
         EZBITSCS(UQ68550 02.212)+00043C S0C4/00000010
         ABEND0C4 IUTLLCXC +2C0 on MVC(PTRTIPAC and XBFL_IUIPL)
             due to overlay of ULP_XBFL
    Overlays in ECSA storage
  CISCO Log Messages like the following:
  %CIP2-3-MSG: slot8 %PACK-3-BADLEN: Invalid length in CLAW packed
  control message - act 3700, exp 32. Path/Dev=8310/00
  %CIP2-6-MSG: slot8 %PACK-6-RANGE2: Out of range sublink(64)
  received in packed claw message. Path/Dev=8310/00
  %CIP2-6-MSG: slot8 %PACK-6-NOCONN: Channel wrote data on sublink
  3 without a valid connection.  Path=8310 device=00 link=01
  %CIP2-3-MSG: slot8 %PACK-3-ILLEN: Not enough data left in buffer
  for packed message - remaining 56, length 25480. Path/Dev=831
  

Local fix

• Turn off packing on the CISCO device (and in the TCPIP
    profile if desired)
  KEYWORDS: CLAW PACKING ABEND0C4 ABEND 0C4 OVERLAY
  

Problem summary

• ****************************************************************
  * USERS AFFECTED: All users of the Communications Server for   *
  *                 z/OS Version 1 Release 2, 4, 5 & 6 IP:       *
  *                 CLAW Packing                                 *
  ****************************************************************
  * PROBLEM DESCRIPTION: Abend0C4 in EZBIFOUT when using packed  *
  *                      buffers over a CLAW device.  Possible   *
  *                      overlay of storage resulting in an      *
  *                      abend0C4 in EZBITSCS.                   *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  The packing code in EZBIFOUT allocates a mini CLAW packing
  buffer when the reusable packing buffers are exhausted and the
  outbound request contains a single packet.  Mini CLAW packing
  buffers are allocated to exactly fit the single outbound packet.
  The blocking algorithm for the device may attempt to insert
  additional packets in the packing buffer, causing an overrun of
  the buffer.  The overrun may cause an Abend0C4 accessing storage
  beyond the buffer or an overlay if the storage is accessible.
  +-------------------------------------------------------------+
  + 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

• EZBIFOUT has been amended to only use mini CLAW packing buffers
  when the blocking factor for the device is zero.
  
  * 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:

  UQ90965 UQ90966 UQ90967

Modules/Macros

• EZBIFOUT
  

Fix information

• Fixed component name

  TCP/IP V3 MVS

• Fixed component ID

  5655HAL00

Applicable component levels

• R120 PSY UQ90965

     UP04/08/19 P F408 Ø

• R140 PSY UQ90582

     UP04/08/19 P F408 Ø

• R150 PSY UQ90966

     UP04/08/19 P F408 Ø

• R160 PSY UQ90967

     UP04/08/19 P F408 Ø

Fix is available

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