LI77290: CRASH IN SNA_V5ROUTER64

Communications Server for Linux, Version 6.2.3 -- Last Fixpack

APAR status

• Closed as program error.

Error description

• Crash occurs during VRN link activation rejection caused by
  misconfigured DNS.
  

Local fix

• Correct DNS configuration.
  

Problem summary

• USERS AFFECTED: All using Enterprise Extender (EE).
  
  PROBLEM DESCRIPTION:
  CRASH INFORMATION:CPU 0 CSA F00000003005F780 at time of
  crash, error code for LEDs:70000000
  pvthread+001700 STACK:
  [047C1E94]sna_v5router64:ncs_check_for_retry+000208
  (F1000100653CA5D8,0100000000000001,F10001002F44E048)
  [047B5218]sna_v5router64:ncs_fsm_ls_ext+0005B0
  (F10001003271AC20,F10001002F44E048)
  [047B2EA8]sna_v5router64:ncs_dlc_to_cs_signals+0001BC
  (F10001003271AC20,F10001002F44E048)
  [047B3B64]sna_v5router64:ncs_queue_handler+0000FC
  (F10001003271AC20,0001000000000001,F10001002F44E048)
  [046A6E70]sna_v5router64:nba_dispatch_input+000290
  (F1000100321A8258,F10001002F44E048)
  [046A755C]sna_v5router64:nba_dispatch_process+0000C8
  (F1000100321A8258,F10001002F44E048)
  [046A7D68]sna_v5router64:nba_scheduler+000210 ()
  [04699F34]sna_v5router64:vpr_stream_lr_svc+0001A8
  (F100020000522000)
  [0411207C]pse:sq_wrapper+00015C (??)
  [040FD358]pse:csq_run+000528 (??)
  [040FC008]pse:csq_lateral+0000BC (??, ??, ??)
  [041129F8]pse:scheduled_run+0000D0 ()
  [001F6070]Netintr+0001A0 ()
  [001F5E8C]netisr_thread+000014 ()
  [0016BD2C]threadentry+000014 (??, ??, ??, ??)
  
  PROBLEM SUMMARY:
  The problem occurs when the following all occur:
  - DNS misconfiguration causes a VRN link activation to
    be rejected (CNCT_OUT RSP ERROR for @Dxxxxxx link in
    the DLC trace)
  - CS then frees internal memory used for this VRN link
  - CS frees memory back to the O/S from its memory cache
    (this does not happen every time)
  - the O/S memory manager clears this memory immediately.
  - CS then tries to access the memory just after it has
    been released.
  

Problem conclusion

• Code has been corrected to prevent checking the retry logic for
  the dynamic link after it had failed to actviate.
  

Temporary fix

Comments

APAR Information

• APAR is sysrouted FROM one or more of the following:

  IV09118

• APAR is sysrouted TO one or more of the following:

Fix information

• Fixed component name

  CS LINUX ON ZSE

• Fixed component ID

  5724I3400

Applicable component levels

• R623 PSY