SOCKET CONNECTION ATTEMPT RECEIVES EAFNOSUPPORT ERROR

 
 APAR Identifier ...... PK52404      Last Changed ........ 08/12/01
 SOCKET CONNECTION ATTEMPT RECEIVES EAFNOSUPPORT ERROR
 
 Symptom ...... IN INCORROUT         Status ........... CLOSED  PER
 Severity ................... 2      Date Closed ......... 08/07/22
 Component .......... 5735FAL00      Duplicate of ........
 Reported Release ......... 520      Fixed Release ............ 999
 Component Name TCP/IP V2 FOR V      Special Notice
 Current Target Date ..              Flags
 SCP ...................
 Platform ............
 
 Status Detail: SHIPMENT - Packaged solution is available for
                           shipment.
 
 PE PTF List:
 
 PTF List:
 Release 520   : UK38330 available 08/07/22 (0802 )
 Release 530   : UK38331 available 08/07/22 (0802 )
 
 Parent APAR:
 Child APAR list:
 
 ERROR DESCRIPTION:
 An attempt to establish a connection with the SSL server is
 rejected with errno 97 (EAFNOSUPPORT).  Initial diagnosis of
 this problem shows this error may be related to a TCP/IP stack
 control block field that has not been correctly initialized
 upon reuse of that control block.  Thus, this problem might
 also arise for non-SSL connection attempts.
 
 LOCAL FIX:
 None.
 
 PROBLEM SUMMARY:
 ****************************************************************
 * USERS AFFECTED: All z/VM TCP/IP users with IPv6 socket       *
 *                 connections.                                 *
 ****************************************************************
 * PROBLEM DESCRIPTION:                                         *
 ****************************************************************
 * RECOMMENDATION: APPLY PTF                                    *
 ****************************************************************
 When a client control block (CCB) is freed, all fields in the
 block should be reset to their null value.  The block is then
 placed on the CCB free chain.
 
 In this scenario, the CCB was previously used for a client
 with IPv6 socket connections.  When the block was freed, the
 ClientApiIpv6 flag did not get reset.  When the CCB was then
 used for a different client, the TCP/IP stack assumed that
 all sockets would be IPv6 sockets.  A bind was then issued
 for an IPv4 socket which confused the stack and forced the
 EAFNOSUPPORT code to be returned.
 
 PROBLEM CONCLUSION:
 The FreeCcb routine in TCQUEUE Pascal has been updated to turn
 off the ClientApiIpv6 flag.
 
 TEMPORARY FIX:
 
 COMMENTS:
 
 MODULES/MACROS:   TCPIP    TCQUEUE
 
 SRLS:      NONE
 
 RTN CODES:
 
 CIRCUMVENTION:
 
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