prevent use-after-free in local printing if dumping immediately after flushing interface.

updating comment.

flushing neighbours associated with flushed interface.

flushing neighbours associated with flushed interface.

Author: tinselcity

interface.c

@@ -101,6 +101,7 @@ int
 flush_interface(char *ifname)
 {
     struct interface *ifp, *prev;
+    struct neighbour *neigh;
 
     prev = NULL;
     ifp = interfaces;
@@ -114,6 +115,18 @@ flush_interface(char *ifname)
     if(ifp == NULL)
         return 0;
 
+    /* flush any neighbours associated with interface */
+    neigh = neighs;
+    while(neigh) {
+        if(neigh->ifp == ifp) {
+            struct neighbour *old = neigh;
+            neigh = neigh->next;
+            flush_neighbour(old);
+            continue;
+        }
+        neigh = neigh->next;
+    }
+
     interface_updown(ifp, 0);
     if(prev)
         prev->next = ifp->next;

neighbour.c

@@ -54,7 +54,7 @@ find_neighbour_nocreate(const unsigned char *address, struct interface *ifp)
     return NULL;
 }
 
-static void
+void
 flush_neighbour(struct neighbour *neigh)
 {
     flush_neighbour_routes(neigh);

neighbour.h

@@ -68,6 +68,7 @@ struct neighbour *find_neighbour(const unsigned char *address,
 int update_neighbour(struct neighbour *neigh, struct hello_history *hist,
                      int unicast, int hello, int hello_interval);
 unsigned check_neighbours(void);
+void flush_neighbour(struct neighbour *neigh);
 unsigned neighbour_txcost(struct neighbour *neigh);
 unsigned neighbour_rxcost(struct neighbour *neigh);
 unsigned neighbour_rttcost(struct neighbour *neigh);