1 files changed, 19 insertions, 26 deletions

diff --git a/net/packet/af_packet.c b/net/packet/af_packet.c
index 737092ca9b4e..1d1483007e46 100644
--- a/net/packet/af_packet.c
+++ b/net/packet/af_packet.c
@@ -247,12 +247,13 @@ static int packet_direct_xmit(struct sk_buff *skb)
 	struct sk_buff *orig_skb = skb;
 	struct netdev_queue *txq;
 	int ret = NETDEV_TX_BUSY;
+	bool again = false;
 
 	if (unlikely(!netif_running(dev) ||
 		     !netif_carrier_ok(dev)))
 		goto drop;
 
-	skb = validate_xmit_skb_list(skb, dev);
+	skb = validate_xmit_skb_list(skb, dev, &again);
 	if (skb != orig_skb)
 		goto drop;
 
@@ -1687,7 +1688,6 @@ static int fanout_add(struct sock *sk, u16 id, u16 type_flags)
 		atomic_long_set(&rollover->num, 0);
 		atomic_long_set(&rollover->num_huge, 0);
 		atomic_long_set(&rollover->num_failed, 0);
-		po->rollover = rollover;
 	}
 
 	if (type_flags & PACKET_FANOUT_FLAG_UNIQUEID) {
@@ -1745,6 +1745,8 @@ static int fanout_add(struct sock *sk, u16 id, u16 type_flags)
 		if (refcount_read(&match->sk_ref) < PACKET_FANOUT_MAX) {
 			__dev_remove_pack(&po->prot_hook);
 			po->fanout = match;
+			po->rollover = rollover;
+			rollover = NULL;
 			refcount_set(&match->sk_ref, refcount_read(&match->sk_ref) + 1);
 			__fanout_link(sk, po);
 			err = 0;
@@ -1758,10 +1760,7 @@ static int fanout_add(struct sock *sk, u16 id, u16 type_flags)
 	}
 
 out:
-	if (err && rollover) {
-		kfree_rcu(rollover, rcu);
-		po->rollover = NULL;
-	}
+	kfree(rollover);
 	mutex_unlock(&fanout_mutex);
 	return err;
 }
@@ -1785,11 +1784,6 @@ static struct packet_fanout *fanout_release(struct sock *sk)
 			list_del(&f->list);
 		else
 			f = NULL;
-
-		if (po->rollover) {
-			kfree_rcu(po->rollover, rcu);
-			po->rollover = NULL;
-		}
 	}
 	mutex_unlock(&fanout_mutex);
 
@@ -3029,6 +3023,7 @@ static int packet_release(struct socket *sock)
 	synchronize_net();
 
 	if (f) {
+		kfree(po->rollover);
 		fanout_release_data(f);
 		kfree(f);
 	}
@@ -3097,6 +3092,10 @@ static int packet_do_bind(struct sock *sk, const char *name, int ifindex,
 	if (need_rehook) {
 		if (po->running) {
 			rcu_read_unlock();
+			/* prevents packet_notifier() from calling
+			 * register_prot_hook()
+			 */
+			po->num = 0;
 			__unregister_prot_hook(sk, true);
 			rcu_read_lock();
 			dev_curr = po->prot_hook.dev;
@@ -3105,6 +3104,7 @@ static int packet_do_bind(struct sock *sk, const char *name, int ifindex,
 								 dev->ifindex);
 		}
 
+		BUG_ON(po->running);
 		po->num = proto;
 		po->prot_hook.type = proto;
 
@@ -3843,7 +3843,6 @@ static int packet_getsockopt(struct socket *sock, int level, int optname,
 	void *data = &val;
 	union tpacket_stats_u st;
 	struct tpacket_rollover_stats rstats;
-	struct packet_rollover *rollover;
 
 	if (level != SOL_PACKET)
 		return -ENOPROTOOPT;
@@ -3922,18 +3921,13 @@ static int packet_getsockopt(struct socket *sock, int level, int optname,
 		       0);
 		break;
 	case PACKET_ROLLOVER_STATS:
-		rcu_read_lock();
-		rollover = rcu_dereference(po->rollover);
-		if (rollover) {
-			rstats.tp_all = atomic_long_read(&rollover->num);
-			rstats.tp_huge = atomic_long_read(&rollover->num_huge);
-			rstats.tp_failed = atomic_long_read(&rollover->num_failed);
-			data = &rstats;
-			lv = sizeof(rstats);
-		}
-		rcu_read_unlock();
-		if (!rollover)
+		if (!po->rollover)
 			return -EINVAL;
+		rstats.tp_all = atomic_long_read(&po->rollover->num);
+		rstats.tp_huge = atomic_long_read(&po->rollover->num_huge);
+		rstats.tp_failed = atomic_long_read(&po->rollover->num_failed);
+		data = &rstats;
+		lv = sizeof(rstats);
 		break;
 	case PACKET_TX_HAS_OFF:
 		val = po->tp_tx_has_off;
@@ -4080,12 +4074,12 @@ static int packet_ioctl(struct socket *sock, unsigned int cmd,
 	return 0;
 }
 
-static unsigned int packet_poll(struct file *file, struct socket *sock,
+static __poll_t packet_poll(struct file *file, struct socket *sock,
 				poll_table *wait)
 {
 	struct sock *sk = sock->sk;
 	struct packet_sock *po = pkt_sk(sk);
-	unsigned int mask = datagram_poll(file, sock, wait);
+	__poll_t mask = datagram_poll(file, sock, wait);
 
 	spin_lock_bh(&sk->sk_receive_queue.lock);
 	if (po->rx_ring.pg_vec) {
@@ -4537,7 +4531,6 @@ static int packet_seq_open(struct inode *inode, struct file *file)
 }
 
 static const struct file_operations packet_seq_fops = {
-	.owner		= THIS_MODULE,
 	.open		= packet_seq_open,
 	.read		= seq_read,
 	.llseek		= seq_lseek,