diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index 279467b74eb70499586e21528842bc99efa1676e..85bb38cb56fd28acd8b18e95b345da085b2cd7ad 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -2567,9 +2567,12 @@ static int packet_release(struct socket *sock) * Attach a packet hook. */ -static int packet_do_bind(struct sock *sk, struct net_device *dev, __be16 protocol) +static int packet_do_bind(struct sock *sk, struct net_device *dev, __be16 proto) { struct packet_sock *po = pkt_sk(sk); + const struct net_device *dev_curr; + __be16 proto_curr; + bool need_rehook; if (po->fanout) { if (dev) @@ -2579,21 +2582,29 @@ static int packet_do_bind(struct sock *sk, struct net_device *dev, __be16 protoc } lock_sock(sk); - spin_lock(&po->bind_lock); - unregister_prot_hook(sk, true); - po->num = protocol; - po->prot_hook.type = protocol; - if (po->prot_hook.dev) - dev_put(po->prot_hook.dev); + proto_curr = po->prot_hook.type; + dev_curr = po->prot_hook.dev; + + need_rehook = proto_curr != proto || dev_curr != dev; + + if (need_rehook) { + unregister_prot_hook(sk, true); - po->prot_hook.dev = dev; - po->ifindex = dev ? dev->ifindex : 0; + po->num = proto; + po->prot_hook.type = proto; + + if (po->prot_hook.dev) + dev_put(po->prot_hook.dev); - packet_cached_dev_assign(po, dev); + po->prot_hook.dev = dev; + + po->ifindex = dev ? dev->ifindex : 0; + packet_cached_dev_assign(po, dev); + } - if (protocol == 0) + if (proto == 0 || !need_rehook) goto out_unlock; if (!dev || (dev->flags & IFF_UP)) {