ISIS Crash on shutting down protocol

[sachinites]

Topology : build_linear_topo( )

Make H1 ---eth1 ---------------------eth1----H2. LAN

Enable protocol on all nodes and all interfaces.
config node H1 protocol isis interface all
config node H2 protocol isis interface all
config node H3 protocol isis interface all
config node H4 protocol isis interface all

config node H1 protocol isis interface eth1 broadcast
config node H2 protocol isis interface eth1 broadcast

config node H2 protocol isis interface eth1 priority 100 config node H1 no protocol isis

Crash is observed.

Difficult to reproduce.