ipv6: prepare rt6_clean_tohost() for exception table
If we move all cached dst into the exception table under the main route,
current rt6_clean_tohost() will no longer be able to access them.
This commit makes fib6_clean_tohost() to also go through all cached
routes in exception table and removes cached gateway routes to the
passed in gateway.
This is a preparation in order to move all cached routes into the
exception table.
Signed-off-by: Wei Wang <weiwan@google.com>
Signed-off-by: Martin KaFai Lau <kafai@fb.com>
Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/route.c b/net/ipv6/route.c
index d9805a8..e8e9015 100644
--- a/net/ipv6/route.c
+++ b/net/ipv6/route.c
@@ -1491,6 +1491,43 @@ static void rt6_exceptions_update_pmtu(struct rt6_info *rt, int mtu)
}
}
+#define RTF_CACHE_GATEWAY (RTF_GATEWAY | RTF_CACHE)
+
+static void rt6_exceptions_clean_tohost(struct rt6_info *rt,
+ struct in6_addr *gateway)
+{
+ struct rt6_exception_bucket *bucket;
+ struct rt6_exception *rt6_ex;
+ struct hlist_node *tmp;
+ int i;
+
+ if (!rcu_access_pointer(rt->rt6i_exception_bucket))
+ return;
+
+ spin_lock_bh(&rt6_exception_lock);
+ bucket = rcu_dereference_protected(rt->rt6i_exception_bucket,
+ lockdep_is_held(&rt6_exception_lock));
+
+ if (bucket) {
+ for (i = 0; i < FIB6_EXCEPTION_BUCKET_SIZE; i++) {
+ hlist_for_each_entry_safe(rt6_ex, tmp,
+ &bucket->chain, hlist) {
+ struct rt6_info *entry = rt6_ex->rt6i;
+
+ if ((entry->rt6i_flags & RTF_CACHE_GATEWAY) ==
+ RTF_CACHE_GATEWAY &&
+ ipv6_addr_equal(gateway,
+ &entry->rt6i_gateway)) {
+ rt6_remove_exception(bucket, rt6_ex);
+ }
+ }
+ bucket++;
+ }
+ }
+
+ spin_unlock_bh(&rt6_exception_lock);
+}
+
struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table,
int oif, struct flowi6 *fl6, int flags)
{
@@ -3240,18 +3277,27 @@ void rt6_remove_prefsrc(struct inet6_ifaddr *ifp)
}
#define RTF_RA_ROUTER (RTF_ADDRCONF | RTF_DEFAULT | RTF_GATEWAY)
-#define RTF_CACHE_GATEWAY (RTF_GATEWAY | RTF_CACHE)
/* Remove routers and update dst entries when gateway turn into host. */
static int fib6_clean_tohost(struct rt6_info *rt, void *arg)
{
struct in6_addr *gateway = (struct in6_addr *)arg;
+ /* RTF_CACHE_GATEWAY case will be removed once the exception
+ * table is hooked up to store all cached routes.
+ */
if ((((rt->rt6i_flags & RTF_RA_ROUTER) == RTF_RA_ROUTER) ||
((rt->rt6i_flags & RTF_CACHE_GATEWAY) == RTF_CACHE_GATEWAY)) &&
ipv6_addr_equal(gateway, &rt->rt6i_gateway)) {
return -1;
}
+
+ /* Further clean up cached routes in exception table.
+ * This is needed because cached route may have a different
+ * gateway than its 'parent' in the case of an ip redirect.
+ */
+ rt6_exceptions_clean_tohost(rt, gateway);
+
return 0;
}
