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path: root/net/packet/af_packet.c
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Diffstat (limited to 'net/packet/af_packet.c')
-rw-r--r--net/packet/af_packet.c83
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);