diff options
| -rw-r--r-- | net/packet/af_packet.c | 31 |
1 files changed, 22 insertions, 9 deletions
diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index 0f03f6a53b4d..70f5b6a4683c 100644 --- a/net/packet/af_packet.c +++ b/net/packet/af_packet.c @@ -1497,6 +1497,8 @@ static void __fanout_link(struct sock *sk, struct packet_sock *po) f->arr[f->num_members] = sk; smp_wmb(); f->num_members++; + if (f->num_members == 1) + dev_add_pack(&f->prot_hook); spin_unlock(&f->lock); } @@ -1513,6 +1515,8 @@ static void __fanout_unlink(struct sock *sk, struct packet_sock *po) BUG_ON(i >= f->num_members); f->arr[i] = f->arr[f->num_members - 1]; f->num_members--; + if (f->num_members == 0) + __dev_remove_pack(&f->prot_hook); spin_unlock(&f->lock); } @@ -1693,7 +1697,6 @@ static int fanout_add(struct sock *sk, u16 id, u16 type_flags) match->prot_hook.func = packet_rcv_fanout; match->prot_hook.af_packet_priv = match; match->prot_hook.id_match = match_fanout_group; - dev_add_pack(&match->prot_hook); list_add(&match->list, &fanout_list); } err = -EINVAL; @@ -1718,7 +1721,12 @@ out: return err; } -static void fanout_release(struct sock *sk) +/* If pkt_sk(sk)->fanout->sk_ref is zero, this function removes + * pkt_sk(sk)->fanout from fanout_list and returns pkt_sk(sk)->fanout. + * It is the responsibility of the caller to call fanout_release_data() and + * free the returned packet_fanout (after synchronize_net()) + */ +static struct packet_fanout *fanout_release(struct sock *sk) { struct packet_sock *po = pkt_sk(sk); struct packet_fanout *f; @@ -1728,17 +1736,17 @@ static void fanout_release(struct sock *sk) if (f) { po->fanout = NULL; - if (atomic_dec_and_test(&f->sk_ref)) { + if (atomic_dec_and_test(&f->sk_ref)) list_del(&f->list); - dev_remove_pack(&f->prot_hook); - fanout_release_data(f); - kfree(f); - } + else + f = NULL; if (po->rollover) kfree_rcu(po->rollover, rcu); } mutex_unlock(&fanout_mutex); + + return f; } static bool packet_extra_vlan_len_allowed(const struct net_device *dev, @@ -2912,6 +2920,7 @@ static int packet_release(struct socket *sock) { struct sock *sk = sock->sk; struct packet_sock *po; + struct packet_fanout *f; struct net *net; union tpacket_req_u req_u; @@ -2951,9 +2960,14 @@ static int packet_release(struct socket *sock) packet_set_ring(sk, &req_u, 1, 1); } - fanout_release(sk); + f = fanout_release(sk); synchronize_net(); + + if (f) { + fanout_release_data(f); + kfree(f); + } /* * Now the socket is dead. No more input will appear. */ @@ -3905,7 +3919,6 @@ static int packet_notifier(struct notifier_block *this, } 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); |