PM52626: EZBIFINB(UK61123 10.302)+009620 S0C4/00000004 SRB

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• TCPIP is processing a complex packing mode buffer from a QDIO
  device.  The packets in the buffer are allocated in multiple
  dataspaces.  EZBIFINB is not switching the ALET value when
  processing the packets, causing incorrect data to be processed
  as the IP header.  This will cause the IUDI to be built with an
  incorrect header offset(dliuhdro) and packet length(dliudatl).
  When EZBIFINB tries to find the start of the header in the data,
  the abend occurs because the offset is greater than the length
  of data in the message triple chain.  This causes an abend0C4
  when the next pointer in the chain is zero.
  
  
  VERIFICATION STEPS:
  1) TCPIP abends in EZBIFINB trying to store into low core.  Reg
  7 is 0.  Reg 4 will point to a SKMB for an IUDI.  The pointer at
  +C will point to a SKMB which has been freed already.
  2) The IUDI will have odd values at offset 104 and 108.  These
  should be the header offset and data length values.
  .
  ADDTIONAL SYMPTOMS:
  Increase in inbound error counts on QDIO devices.
  

Local fix

Problem summary

• ****************************************************************
  * USERS AFFECTED: All users of the IBM Communications Server   *
  *                 for z/OS Version 1 Release(s) 11, 12, and    *
  *                 13 IP                                        *
  ****************************************************************
  * PROBLEM DESCRIPTION: Abend0C4 in EZBIFINB performing complex *
  *                      mode unpacking.                         *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  Abend0C4 in EZBIFINB performing complex mode unpacking.
  
  QDIO and IQDIO devices use read buffers backed by CSM dataspace
  storage.  The read buffers are presented to EZBIFINB which is
  responsible for creating an IUDI representing each packet.  In
  complex mode unpacking the packet headers are moved into the
  IUDI and the payload remains in CSM dataspace storage.  Complex
  mode unpacking is dynamically activated when the device is
  historically receiving large packets.
  The typical environment will have a single CSM dataspace however
  under heavy storage requirements additional dataspaces will be
  used.  The abend occurs when EZBIFINB is presented with multiple
  read buffers that are backed by different CSM dataspaces.  The
  move of the packet headers are all performed using the ALET from
  the last read buffer that is ready.
  The complex mode unpacking logic should be using the ALET that
  is associated with the read buffer being processed.
  +-------------------------------------------------------------+
  + 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

• EZBIFINB has been amended to use the ALET associated with the
  read buffer when performing complex mode unpacking.
  
  * 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:

  UK75325 UK75326 UK75327

Modules/Macros

• EZBIFINB
  

Fix information

• Fixed component name

  TCP/IP V3 MVS

• Fixed component ID

  5655HAL00

Applicable component levels

• R1B0 PSY UK75325

     UP12/02/14 P F202

• R1C0 PSY UK75326

     UP12/02/14 P F202

• R1D0 PSY UK75327

     UP12/02/14 P F202

Fix is available

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