ipv4: Properly purge netdev references on uncached routes.

When a device is unregistered, we have to purge all of the
references to it that may exist in the entire system.

If a route is uncached, we currently have no way of accomplishing
this.

So create a global list that is scanned when a network device goes
down.  This mirrors the logic in net/core/dst.c's dst_ifdown().

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 3 insertions, 0 deletions

diff --git a/include/net/route.h b/include/net/route.h
index 8c52bc6f1c90..776a27f1ab78 100644
--- a/include/net/route.h
+++ b/include/net/route.h
@@ -57,6 +57,8 @@ struct rtable {
 
         /* Miscellaneous cached information */
         u32                     rt_pmtu;
+
+        struct list_head        rt_uncached;
 };
 
 static inline bool rt_is_input_route(const struct rtable *rt)
@@ -107,6 +109,7 @@ extern struct ip_rt_acct __percpu *ip_rt_acct;
 struct in_device;
 extern int              ip_rt_init(void);
 extern void             rt_cache_flush(struct net *net, int how);
+extern void             rt_flush_dev(struct net_device *dev);
 extern struct rtable *__ip_route_output_key(struct net *, struct flowi4 *flp);
 extern struct rtable *ip_route_output_flow(struct net *, struct flowi4 *flp,
                                            struct sock *sk);