isisd: fix crash on "no router isis" (BZ#536)

The crash is due to threads accessing data that gets destroyed
during the removal of the configuration.

* isis_circuit.c: Destroy adjacencies to stop adjacency expiry thread.
  Stop PSNP threads.
* isisd.c: Change state of circuit back to INIT and reassign the
  circuit structure to isis->init_circ_list rather than destroying
  the circuit data structure. Stop SPF threads. Stop LSP generation
  threads.
* isisd.h: Add pointers to LSP threads into area structure in order to
  stop them in isisd.c
* isis_lsp.c: Store pointer to LSP thread in area structure.
* isis_pdu.c: Stop PDU generation for a circuit with a removed area.
* isis_pfpacket.c: Stop processing received PDUs for a circuit with a
  removed area.

1 files changed, 12 insertions, 0 deletions

diff --git a/isisd/isis_circuit.c b/isisd/isis_circuit.c
index d2923b57..e34d491a 100644
--- a/isisd/isis_circuit.c
+++ b/isisd/isis_circuit.c
@@ -142,6 +142,11 @@ isis_circuit_deconfigure (struct isis_circuit *circuit,
 			  struct isis_area *area)
 {
 
+  /* destroy adjacencies */
+  if (circuit->u.bc.adjdb[0])
+    isis_adjdb_iterate (circuit->u.bc.adjdb[0], (void(*) (struct isis_adjacency *, void *)) isis_delete_adj, circuit->u.bc.adjdb[0]);
+  if (circuit->u.bc.adjdb[1])
+    isis_adjdb_iterate (circuit->u.bc.adjdb[1], (void(*) (struct isis_adjacency *, void *)) isis_delete_adj, circuit->u.bc.adjdb[1]);
   /* Remove circuit from area */
   listnode_delete (area->circuit_list, circuit);
   /* Free the index of SRM and SSN flags */
@@ -602,6 +607,13 @@ isis_circuit_down (struct isis_circuit *circuit)
     {
       THREAD_TIMER_OFF (circuit->u.p2p.t_send_p2p_hello);
     }
+
+  if (circuit->t_send_psnp[0]) {
+    THREAD_TIMER_OFF (circuit->t_send_psnp[0]);
+  }
+  if (circuit->t_send_psnp[1]) {
+    THREAD_TIMER_OFF (circuit->t_send_psnp[1]);
+  }
   /* close the socket */
   close (circuit->fd);