net/ipv6: Move call_fib6_entry_notifiers up for route adds

Move call to call_fib6_entry_notifiers for new IPv6 routes to right
before the insertion into the FIB. At this point notifier handlers can
decide the fate of the new route with a clean path to delete the
potential new entry if the notifier returns non-0.

Signed-off-by: David Ahern <dsa@cumulusnetworks.com>
Reviewed-by: Ido Schimmel <idosch@mellanox.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --git a/net/ipv6/ip6_fib.c b/net/ipv6/ip6_fib.c
index 908b8e5b615a928c6ebdb0475cde62a5558e9c6c..deab2db6692eb526e88c85c5e9e20e52020c9e94 100644 (file)
--- a/net/ipv6/ip6_fib.c
+++ b/net/ipv6/ip6_fib.c
@@ -1007,12 +1007,16 @@ add:
                if (err)
                        return err;
 
+               err = call_fib6_entry_notifiers(info->nl_net,
+                                               FIB_EVENT_ENTRY_ADD,
+                                               rt, extack);
+               if (err)
+                       return err;
+
                rcu_assign_pointer(rt->rt6_next, iter);
                atomic_inc(&rt->rt6i_ref);
                rcu_assign_pointer(rt->rt6i_node, fn);
                rcu_assign_pointer(*ins, rt);
-               call_fib6_entry_notifiers(info->nl_net, FIB_EVENT_ENTRY_ADD,
-                                         rt, extack);
                if (!info->skip_notify)
                        inet6_rt_notify(RTM_NEWROUTE, rt, info, nlflags);
                info->nl_net->ipv6.rt6_stats->fib_rt_entries++;
@@ -1036,12 +1040,16 @@ add:
                if (err)
                        return err;
 
+               err = call_fib6_entry_notifiers(info->nl_net,
+                                               FIB_EVENT_ENTRY_REPLACE,
+                                               rt, extack);
+               if (err)
+                       return err;
+
                atomic_inc(&rt->rt6i_ref);
                rcu_assign_pointer(rt->rt6i_node, fn);
                rt->rt6_next = iter->rt6_next;
                rcu_assign_pointer(*ins, rt);
-               call_fib6_entry_notifiers(info->nl_net, FIB_EVENT_ENTRY_REPLACE,
-                                         rt, extack);
                if (!info->skip_notify)
                        inet6_rt_notify(RTM_NEWROUTE, rt, info, NLM_F_REPLACE);
                if (!(fn->fn_flags & RTN_RTINFO)) {