misc/120332: Kernel Panic/Crash when adding a certain IP address

[Jurgen Weber]

>Number:         120332
>Category:       misc
>Synopsis:       Kernel Panic/Crash when adding a certain IP address
>Confidential:   no
>Severity:       serious
>Priority:       medium
>Responsible:    freebsd-bugs
>State:          open
>Quarter:        
>Keywords:       
>Date-Required:
>Class:          sw-bug
>Submitter-Id:   current-users
>Arrival-Date:   Wed Feb 06 23:20:01 UTC 2008
>Closed-Date:
>Last-Modified:
>Originator:     Jurgen Weber
>Release:        FreeBSD 7.0-RC1
>Organization:
>Environment:
FreeBSD <servername> 7.0-RC1 FreeBSD 7.0-RC1 #0: Mon Dec 24 12:18:24 UTC 2007     root at logan.cse.buffalo.edu:/usr/obj/usr/src/sys/GENERIC  i386

>Description:
When adding a certain IP address to any of the NIC's in the system it would crash reboot within 2 minuts of booting up. After some investigation and mucking about wiht NIC's I worked out it was a particular IP address. 10.10.10.9.

oot at clashserver /usr/src/sys/i386]# kgdb /boot/kernel/kernel.symbols /var/crash/vmcore.0
[GDB will not be able to debug user-mode threads: /usr/lib/libthread_db.so: Undefined symbol "ps_pglobal_lookup"]
GNU gdb 6.1.1 [FreeBSD]
Copyright 2004 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you are
welcome to change it and/or distribute copies of it under certain conditions.
Type "show copying" to see the conditions.
There is absolutely no warranty for GDB.  Type "show warranty" for details.
This GDB was configured as "i386-marcel-freebsd".


Unread portion of the kernel message buffer:
kernel trap 12 with interrupts disabled


Fatal trap 12: page fault while in kernel mode
cpuid = 1; apic id = 01
fault virtual address	= 0x18
fault code		= supervisor read, page not present
instruction pointer	= 0x20:0xc07851c5
stack pointer	        = 0x28:0xe6883a48
frame pointer	        = 0x28:0xe6883a64
code segment		= base 0x0, limit 0xfffff, type 0x1b
			= DPL 0, pres 1, def32 1, gran 1
processor eflags	= resume, IOPL = 0
current process		= 476 (nfsd)
trap number		= 12
panic: page fault
cpuid = 1
Uptime: 25s
Physical memory: 1011 MB
Dumping 157 MB: 142 126 110 94 78 62 46 30 14

#0  doadump () at pcpu.h:195
195	pcpu.h: No such file or directory.

## note:
I have a debian system also, which had an fstab entry to mount a directory which was not in exports, this system was untouched thou (eg. I didn't try and mount it).

>How-To-Repeat:
I could repeat the problem by just going

ifconfig em0 add 10.10.10.9 netmask 255.255.0.0
>Fix:
IP address in question 10.10.10.9/16 network. I used 10.10.10.11 with no problems.

After getting that dump I noticed nfsd was the problem. 
NFSD server was active
/etc/exports
      /raid (rw)

I hashed out that line in exports and disabled the nfsd.

System is now stable.



>Release-Note:
>Audit-Trail:
>Unformatted: