IV24025: RPC.MOUNTD MAY CRASH IN READ_FOR_GROUP APPLIES TO AIX 7100-00

Obtain the fix for this APAR.

APAR status

• Closed as program error.

Error description

• If the /etc/netgroup has a network group with
  continuation lines, ending in a newline, e.g.:
  netgroup1 \
  ...
  (host9,-,)    (host9.hal.com,-,) \
  
  #preceding line left BLANK to terminate
  #the previous continuation line
  
  then the rpc.mountd daemon (or any process
  calling the getnetgrent function) may crash
  in the read_for_group function while parsing
  that netgroup entry.  The crashes may happen
  only occasionally.  The rpc.mountd stack trace
  is:
  dbx) where
  .() at 0xf0e8
  read_for_group(??, ??) at 0xd0254370
  parse_netgrp(??, ??) at 0xd02548cc
  lcl_ng.ng_rewind(??, ??) at 0xd0254d9c
  gen_ng.ng_next(??, ??, ??, ??) at 0xd0283e44
  getnetgrent(??, ??, ??) at 0xd021fc90
  calleripis(??, ??) at 0x10000888
  callerisinlist(??, ??, ??) at 0x1000100c
  checkaccess(??, ??, ??) at 0x10002ea4
  chk_access(??, ??, ??, ??, ??) at 0x100033c0
  mountd.mount(??) at 0x10005518
  mnt(??, ??) at 0x10005f98
  _svc_prog_dispatch(??, ??, ??) at 0xd066a7e0
  _svc_run_mt() at 0xd066d4dc
  

Local fix

• Do not use a terminating empty line in the
  /etc/netgroup file netgroup definitions.
  

Problem summary

• #preceding line left BLANK to terminateetnetgrent() to read the
  #the previous continuation line/netgroup, may crash in
  read_for_group() if /etc/netgroup has a network
  group with continuation lines, ending in a newline. e.g.:
  netgroup1
  
  The crashes may happen only occasionally. The rpc.mountd stack
  trace is:
  dbx) where
  .() at 0xf0e8
  read_for_group(??, ??) at 0xd0254370
  parse_netgrp(??, ??) at 0xd02548cc
  lcl_ng.ng_rewind(??, ??) at 0xd0254d9c
  gen_ng.ng_next(??, ??, ??, ??) at 0xd0283e44
  getnetgrent(??, ??, ??) at 0xd021fc90
  calleripis(??, ??) at 0x10000888
  callerisinlist(??, ??, ??) at 0x1000100c
  checkaccess(??, ??, ??) at 0x10002ea4
  chk_access(??, ??, ??, ??, ??) at 0x100033c0
  mountd.mount(??) at 0x10005518
  mnt(??, ??) at 0x10005f98
  _svc_prog_dispatch(??, ??, ??) at 0xd066a7e0
  _svc_run_mt() at 0xd066d4dc
  

Problem conclusion

• Added a check in the code to parse the blank lines in
  /etc/netgroup correctly.
  

Temporary fix

Comments

APAR Information

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

  IV19596

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

  U853583

Fix information

• Fixed component name

  AIX V7.1

• Fixed component ID

  5765H4000

Applicable component levels

• R710 PSY U853583

     UP12/08/09 I 1000