ipv6: initialize route null entry in addrconf_init()

[ Upstream commit 2f460933f58eee3393aba64f0f6d14acb08d1724 ]

Andrey reported a crash on init_net.ipv6.ip6_null_entry->rt6i_idev
since it is always NULL.

This is clearly wrong, we have code to initialize it to loopback_dev,
unfortunately the order is still not correct.

loopback_dev is registered very early during boot, we lose a chance
to re-initialize it in notifier. addrconf_init() is called after
ip6_route_init(), which means we have no chance to correct it.

Fix it by moving this initialization explicitly after
ipv6_add_dev(init_net.loopback_dev) in addrconf_init().

Reported-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: Cong Wang <xiyou.wangcong@gmail.com>
Tested-by: Andrey Konovalov <andreyknvl@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

1 files changed, 1 insertions, 0 deletions

diff --git a/include/net/ip6_route.h b/include/net/ip6_route.h
index f83e78d071a3..2e347d4545cf 100644
--- a/include/net/ip6_route.h
+++ b/include/net/ip6_route.h
@@ -84,6 +84,7 @@ struct dst_entry *ip6_route_lookup(struct net *net, struct flowi6 *fl6,
 struct rt6_info *ip6_pol_route(struct net *net, struct fib6_table *table,
                                int ifindex, struct flowi6 *fl6, int flags);
 
+void ip6_route_init_special_entries(void);
 int ip6_route_init(void);
 void ip6_route_cleanup(void);