ipv6: don't call fib6_run_gc() until routing is ready

When loading the ipv6 module, ndisc_init() is called before
ip6_route_init(). As the former registers a handler calling
fib6_run_gc(), this opens a window to run the garbage collector
before necessary data structures are initialized. If a network
device is initialized in this window, adding MAC address to it
triggers a NETDEV_CHANGEADDR event, leading to a crash in
fib6_clean_all().

Take the event handler registration out of ndisc_init() into a
separate function ndisc_late_init() and move it after
ip6_route_init().

Signed-off-by: Michal Kubecek <mkubecek@suse.cz>
Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 2 insertions, 0 deletions

diff --git a/include/net/ndisc.h b/include/net/ndisc.h
index 3c4211f0bed6..ea0cc26ab70e 100644
--- a/include/net/ndisc.h
+++ b/include/net/ndisc.h
@@ -190,7 +190,9 @@ static inline struct neighbour *__ipv6_neigh_lookup(struct net_device *dev, cons
 }
 
 extern int                      ndisc_init(void);
+extern int                      ndisc_late_init(void);
 
+extern void                     ndisc_late_cleanup(void);
 extern void                     ndisc_cleanup(void);
 
 extern int                      ndisc_rcv(struct sk_buff *skb);