misc/85810: nslookup/dig Hang and processes cannot be killed

[Jason Gardiner]

>Number:         85810
>Category:       misc
>Synopsis:       nslookup/dig Hang and processes cannot be killed
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Tue Sep 06 20:30:10 GMT 2005
>Closed-Date:
>Last-Modified:
>Originator:     Jason Gardiner
>Release:        5.4
>Organization:
Sprint
>Environment:
FreeBSD config-east.sprintlink.net 5.4-RELEASE FreeBSD 5.4-RELEASE #0: Sat Sep  3 01:02:55 EDT 2005     root at config-east.sprintlink.net:/usr/src/sys/i386/compile/GENERIC-SMP  i386

>Description:
Running either a dig or nslookup frequently causes the shell window to hand after returning the query response but before returning a prompt.  ^C or ^D do not stop the process.

Non-authoritative answer:
Name:   www.usair.com
Address: 151.193.204.72
> exit

^C^C^C^D
^D
^C^C^C
               

Later, I noticed that the processes are still running.  I attempted to perform a kill -9, a killall -9 and a kill -17, but the processes remain:

config-east# ps -aux | grep nslookup
root      6418  0.0  0.1  4196  2560  p0- R     1:57PM   0:00.01 nslookup
twit     86489  0.0  0.1  4060  2352  p0- R    10:02AM   0:00.01 nslookup elle
gardiner 86512  0.0  0.1  4060  2452  p0- R    10:04AM   0:00.01 nslookup jay
gardiner 90668  0.0  0.1  4060  2452  p0- R    10:34AM   0:00.01 nslookup www.
twit     12643  0.0  0.1  4060  2420  p1  T+    3:47PM   0:00.01 nslookup sl-b
gardiner  6407  0.0  0.1  3976  2364  p3- R     1:57PM   0:00.01 nslookup
gardiner 90680  0.0  0.1  4124  2516  p3- R    10:35AM   0:00.01 nslookup


I tried dig, with the same results.  I built BIND9 from the ports and used the newly built resolver with the same results.  Environment settings appear to have no effect.

This is an almost generic kernel rebuild.  The only settings changed were 
options SMP
options         SCHED_ULE


>How-To-Repeat:
Perform nslookup either from a command line or interactive.
>Fix:
      
>Release-Note:
>Audit-Trail:
>Unformatted: