PI56009: EDGE LB FOR IPV4 LLB V8.5 CRASH ON AIX 7.1 PPC WHEN IFORWARDPACKET MBUF IS NULL

8.5.5.9: WebSphere Application Server V8.5.5 Fix Pack 9
8.5.5.10: WebSphere Application Server V8.5.5 Fix Pack 10
8.5.5.11: WebSphere Application Server V8.5.5 Fix Pack 11
8.0.0.13: WebSphere Application Server V8.0 Fix Pack 13
8.5.5.12: WebSphere Application Server V8.5.5 Fix Pack 12
8.0.0.14: WebSphere Application Server V8.0 Fix Pack 14
8.5.5.13: WebSphere Application Server V8.5.5 Fix Pack 13
8.0.0.15: WebSphere Application Server V8.0 Fix Pack 15
8.5.5.14: WebSphere Application Server V8.5.5 Fix Pack 14
8.5.5.15: WebSphere Application Server V8.5.5 Fix Pack 15
8.5.5.17: WebSphere Application Server V8.5.5 Fix Pack 17
8.5.5.20: WebSphere Application Server V8.5.5.20
8.5.5.18: WebSphere Application Server V8.5.5 Fix Pack 18
8.5.5.19: WebSphere Application Server V8.5.5 Fix Pack 19
8.5.5.16: WebSphere Application Server V8.5.5 Fix Pack 16
8.5.5.21: WebSphere Application Server V8.5.5.21

APAR status

• Closed as program error.

Error description

• Edge LB for IPV4 LLB v8.5.0.1 crashes on AIX 7.1 ppc when
  iForwardPacket mbuf is null. Suspected to be caused by
  duplicate ip of backend server condition due to migration or
  config of backend servers.
  

Local fix

• Eliminate the duplicate ip condition on subnet.
  

Problem summary

• ****************************************************************
  * USERS AFFECTED:  IBM WebSphere Application Server Load       *
  *                  Balancer for ipv4 users                     *
  ****************************************************************
  * PROBLEM DESCRIPTION: A crash can occur in iForwardPacket     *
  *                      when the adapter is removed from the    *
  *                      network.                                *
  ****************************************************************
  * RECOMMENDATION:                                              *
  ****************************************************************
  A crash can occur from referencing a null pointer in the
  iForwardPacket function when the adapter is removed from the
  network.
  

Problem conclusion

• Corrected the code to exit if the mbuf pointer is null which
  prevents the crash.
  
  Fix levels :
     7.0.0.37
     8.0.0.11
     8.5.5.9
  Does not affect the Load Balancer for ipv4 and ipv6
  

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:

Fix information

• Fixed component name

  WEBS LOAD BALAN

• Fixed component ID

  5724H8811

Applicable component levels

• R700 PSY

     UP

• R800 PSY

     UP

• R850 PSY

     UP