packet: call fanout_release, while UNREGISTERING a netdev

commit 6664498280cf17a59c3e7cf1a931444c02633ed1 upstream.

If a socket has FANOUT sockopt set, a new proto_hook is registered
as part of fanout_add(). When processing a NETDEV_UNREGISTER event in
af_packet, __fanout_unlink is called for all sockets, but prot_hook which was
registered as part of fanout_add is not removed. Call fanout_release, on a
NETDEV_UNREGISTER, which removes prot_hook and removes fanout from the
fanout_list.

This fixes BUG_ON(!list_empty(&dev->ptype_specific)) in netdev_run_todo()

Signed-off-by: Anoob Soman <anoob.soman@citrix.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
Signed-off-by: Willy Tarreau <w@1wt.eu>

diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
index 2d454a235e84f3624585b0e67cad8060808cf937..24f006623f7c4f434d38228e11127be7eb36a3f9 100644 (file)
--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -3384,6 +3384,7 @@ static int packet_notifier(struct notifier_block *this, unsigned long msg, void
                                }
                                if (msg == NETDEV_UNREGISTER) {
                                        packet_cached_dev_reset(po);
+                                       fanout_release(sk);
                                        po->ifindex = -1;
                                        if (po->prot_hook.dev)
                                                dev_put(po->prot_hook.dev);