Bug 31147

The problem is in frequent kernel panic (fatal double fault). It occurs once a day in average. Since August 2001, there were no more than 3 days of server's uptime.
Last week it happend in the following functions:
1) eip = 0xc01e829e
   c01e8298 T ip_output
2) eip = 0xc01f395e
   c01f3958 T fr_makefrip
3) eip = 0xc01f4424
   c01f4424 T fr_check
4) eip = 0xc01ef94f
   c01ef94c T tcp_rtlookup

How-To-Repeat: 1) Kernel configuration is derived from GENERIC but:
options 	IPFIREWALL
options 	IPFIREWALL_FORWARD
options 	IPFIREWALL_VERBOSE_LIMIT=100
options 	IPFIREWALL_DEFAULT_TO_ACCEPT
options 	IPDIVERT
options 	IPFILTER
options 	IPFILTER_LOG
options 	IPSTEALTH

2) /etc/firewall.rules
add deny icmp from any to any frag
add pass icmp from any to any
add pass udp from any to any 53,161,514
add pass udp from any 53,161,514 to any
add fwd 216.55.6.182,8080 tcp from any to 216.55.15.17 80
add fwd 216.55.6.182,25 tcp from any to any 2525
add pass tcp from any to any smtp,http,ftp,ftp\-data,pop3,https,telnet,ssh
add pass tcp from any smtp,http,ftp,ftp\-data,pop3,https,telnet,ssh to any
add pass tcp from any to any 2525,3128,3514,8080,40202
add pass tcp from any 2525,3128,3514,8080,40202 to any
add pass all from any to any via lo0
add deny all from any to 127.0.0.0/8
add deny tcp from any to any 3306 via fxp0
add 65000 deny all from any to any

3) Hardware is:
Celeron 733,
128Mb ECC SDRAM,
i810E chipset,
Intel Pro 10/100B/100+ Ethernet
a couple of 30Gb IDE HDDs: IBM-DTLA-307030

4) The server was OK for about 6 months. Now it reboots almost everyday. Probably, it's a kind of specific traffic that nukes this server.