Ability to live lock 5.3 via routing...

[Sean Chittenden]

Pretty easy for me to reproduce.  The machine live locks so I can't get 
anything out of it, serial console or otherwise.  :(  Imagine a machine 
with two NICs, fxp0 and fxp1 (though it could be any two NICs).  The 
following commands should lead to a lock:

# Add the primary address on the external NIC
ifconfig fxp0 192.168.1.2 netmask 255.255.255.0 media 100baseTX 
mediaopt full-duplex

# Add the default gateway
route add default 192.168.1.1

# Add a network to the internal interface
ifconfig fxp1 10.10.10.1 netmask 255.255.255.0 media 100baseTX mediaopt 
full-duplex

# On the external interface, on the same VLAN, there are two other 
networks.
# Add aliases that way the machine can participate on those networks.
ifconfig fxp0 alias 192.168.2.250 netmask 255.255.255.255
ifconfig fxp0 alias 192.168.3.250 netmask 255.255.255.255

# Add a route so that machines on the internal network can get
# to the 192.168.2.0/24 network.  This command succeeds.
route add -net 192.168.2.250/24 192.168.2.250

# Add a route so that machines on the internal network can also
# get to the 192.168.3.0/24 network.  This command results in a hard
# lock of the system.
route add -net 192.168.3.250/24 192.168.3.250


I'm unable to debug this problem further.  Can someone shed some light 
onto this and/or help me debug it further?  As I've said, I can't even 
break to a debugger or get at the machine via a serial connection.  :(  
Help?  -sc

-- 
Sean Chittenden