diff options
Diffstat (limited to 'net/packet/af_packet.c')
-rw-r--r-- | net/packet/af_packet.c | 83 |
1 files changed, 51 insertions, 32 deletions
diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c index b9e1a13b4ba3..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); } @@ -1619,6 +1623,7 @@ static void fanout_release_data(struct packet_fanout *f) static int fanout_add(struct sock *sk, u16 id, u16 type_flags) { + struct packet_rollover *rollover = NULL; struct packet_sock *po = pkt_sk(sk); struct packet_fanout *f, *match; u8 type = type_flags & 0xff; @@ -1641,23 +1646,28 @@ static int fanout_add(struct sock *sk, u16 id, u16 type_flags) return -EINVAL; } + mutex_lock(&fanout_mutex); + + err = -EINVAL; if (!po->running) - return -EINVAL; + goto out; + err = -EALREADY; if (po->fanout) - return -EALREADY; + goto out; if (type == PACKET_FANOUT_ROLLOVER || (type_flags & PACKET_FANOUT_FLAG_ROLLOVER)) { - po->rollover = kzalloc(sizeof(*po->rollover), GFP_KERNEL); - if (!po->rollover) - return -ENOMEM; - atomic_long_set(&po->rollover->num, 0); - atomic_long_set(&po->rollover->num_huge, 0); - atomic_long_set(&po->rollover->num_failed, 0); + err = -ENOMEM; + rollover = kzalloc(sizeof(*rollover), GFP_KERNEL); + if (!rollover) + goto out; + atomic_long_set(&rollover->num, 0); + atomic_long_set(&rollover->num_huge, 0); + atomic_long_set(&rollover->num_failed, 0); + po->rollover = rollover; } - mutex_lock(&fanout_mutex); match = NULL; list_for_each_entry(f, &fanout_list, list) { if (f->id == id && @@ -1687,7 +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; @@ -1704,36 +1713,40 @@ static int fanout_add(struct sock *sk, u16 id, u16 type_flags) } } out: - mutex_unlock(&fanout_mutex); - if (err) { - kfree(po->rollover); + if (err && rollover) { + kfree(rollover); po->rollover = NULL; } + mutex_unlock(&fanout_mutex); 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; + mutex_lock(&fanout_mutex); f = po->fanout; - if (!f) - return; + if (f) { + po->fanout = NULL; - mutex_lock(&fanout_mutex); - po->fanout = NULL; + if (atomic_dec_and_test(&f->sk_ref)) + list_del(&f->list); + else + f = NULL; - if (atomic_dec_and_test(&f->sk_ref)) { - list_del(&f->list); - dev_remove_pack(&f->prot_hook); - fanout_release_data(f); - kfree(f); + if (po->rollover) + kfree_rcu(po->rollover, rcu); } mutex_unlock(&fanout_mutex); - if (po->rollover) - kfree_rcu(po->rollover, rcu); + return f; } static bool packet_extra_vlan_len_allowed(const struct net_device *dev, @@ -1976,7 +1989,7 @@ static int packet_rcv_vnet(struct msghdr *msg, const struct sk_buff *skb, return -EINVAL; *len -= sizeof(vnet_hdr); - if (virtio_net_hdr_from_skb(skb, &vnet_hdr, vio_le())) + if (virtio_net_hdr_from_skb(skb, &vnet_hdr, vio_le(), true)) return -EINVAL; return memcpy_to_msg(msg, (void *)&vnet_hdr, sizeof(vnet_hdr)); @@ -2237,7 +2250,7 @@ static int tpacket_rcv(struct sk_buff *skb, struct net_device *dev, if (po->has_vnet_hdr) { if (virtio_net_hdr_from_skb(skb, h.raw + macoff - sizeof(struct virtio_net_hdr), - vio_le())) { + vio_le(), true)) { spin_lock(&sk->sk_receive_queue.lock); goto drop_n_account; } @@ -2755,7 +2768,7 @@ static int packet_snd(struct socket *sock, struct msghdr *msg, size_t len) struct virtio_net_hdr vnet_hdr = { 0 }; int offset = 0; struct packet_sock *po = pkt_sk(sk); - int hlen, tlen; + int hlen, tlen, linear; int extra_len = 0; /* @@ -2816,8 +2829,9 @@ static int packet_snd(struct socket *sock, struct msghdr *msg, size_t len) err = -ENOBUFS; hlen = LL_RESERVED_SPACE(dev); tlen = dev->needed_tailroom; - skb = packet_alloc_skb(sk, hlen + tlen, hlen, len, - __virtio16_to_cpu(vio_le(), vnet_hdr.hdr_len), + linear = __virtio16_to_cpu(vio_le(), vnet_hdr.hdr_len); + linear = max(linear, min_t(int, len, dev->hard_header_len)); + skb = packet_alloc_skb(sk, hlen + tlen, hlen, len, linear, msg->msg_flags & MSG_DONTWAIT, &err); if (skb == NULL) goto out_unlock; @@ -2906,6 +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; @@ -2945,9 +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. */ @@ -3899,7 +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); |