1 files changed, 45 insertions, 16 deletions

diff --git a/net/ax25/af_ax25.c b/net/ax25/af_ax25.c
index 363d47f94532..4c7030ed8d33 100644
--- a/net/ax25/af_ax25.c
+++ b/net/ax25/af_ax25.c
@@ -62,12 +62,12 @@ static void ax25_free_sock(struct sock *sk)
  */
 static void ax25_cb_del(ax25_cb *ax25)
 {
+	spin_lock_bh(&ax25_list_lock);
 	if (!hlist_unhashed(&ax25->ax25_node)) {
-		spin_lock_bh(&ax25_list_lock);
 		hlist_del_init(&ax25->ax25_node);
-		spin_unlock_bh(&ax25_list_lock);
 		ax25_cb_put(ax25);
 	}
+	spin_unlock_bh(&ax25_list_lock);
 }
 
 /*
@@ -81,6 +81,7 @@ static void ax25_kill_by_device(struct net_device *dev)
 
 	if ((ax25_dev = ax25_dev_ax25dev(dev)) == NULL)
 		return;
+	ax25_dev->device_up = false;
 
 	spin_lock_bh(&ax25_list_lock);
 again:
@@ -91,6 +92,7 @@ again:
 				spin_unlock_bh(&ax25_list_lock);
 				ax25_disconnect(s, ENETUNREACH);
 				s->ax25_dev = NULL;
+				ax25_cb_del(s);
 				spin_lock_bh(&ax25_list_lock);
 				goto again;
 			}
@@ -103,6 +105,7 @@ again:
 				dev_put_track(ax25_dev->dev, &ax25_dev->dev_tracker);
 				ax25_dev_put(ax25_dev);
 			}
+			ax25_cb_del(s);
 			release_sock(sk);
 			spin_lock_bh(&ax25_list_lock);
 			sock_put(sk);
@@ -995,9 +998,11 @@ static int ax25_release(struct socket *sock)
 	if (sk->sk_type == SOCK_SEQPACKET) {
 		switch (ax25->state) {
 		case AX25_STATE_0:
-			release_sock(sk);
-			ax25_disconnect(ax25, 0);
-			lock_sock(sk);
+			if (!sock_flag(ax25->sk, SOCK_DEAD)) {
+				release_sock(sk);
+				ax25_disconnect(ax25, 0);
+				lock_sock(sk);
+			}
 			ax25_destroy_socket(ax25);
 			break;
 
@@ -1053,11 +1058,13 @@ static int ax25_release(struct socket *sock)
 		ax25_destroy_socket(ax25);
 	}
 	if (ax25_dev) {
-		del_timer_sync(&ax25->timer);
-		del_timer_sync(&ax25->t1timer);
-		del_timer_sync(&ax25->t2timer);
-		del_timer_sync(&ax25->t3timer);
-		del_timer_sync(&ax25->idletimer);
+		if (!ax25_dev->device_up) {
+			del_timer_sync(&ax25->timer);
+			del_timer_sync(&ax25->t1timer);
+			del_timer_sync(&ax25->t2timer);
+			del_timer_sync(&ax25->t3timer);
+			del_timer_sync(&ax25->idletimer);
+		}
 		dev_put_track(ax25_dev->dev, &ax25_dev->dev_tracker);
 		ax25_dev_put(ax25_dev);
 	}
@@ -1654,9 +1661,12 @@ static int ax25_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
 			int flags)
 {
 	struct sock *sk = sock->sk;
-	struct sk_buff *skb;
+	struct sk_buff *skb, *last;
+	struct sk_buff_head *sk_queue;
 	int copied;
 	int err = 0;
+	int off = 0;
+	long timeo;
 
 	lock_sock(sk);
 	/*
@@ -1668,11 +1678,29 @@ static int ax25_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
 		goto out;
 	}
 
-	/* Now we can treat all alike */
-	skb = skb_recv_datagram(sk, flags & ~MSG_DONTWAIT,
-				flags & MSG_DONTWAIT, &err);
-	if (skb == NULL)
-		goto out;
+	/*  We need support for non-blocking reads. */
+	sk_queue = &sk->sk_receive_queue;
+	skb = __skb_try_recv_datagram(sk, sk_queue, flags, &off, &err, &last);
+	/* If no packet is available, release_sock(sk) and try again. */
+	if (!skb) {
+		if (err != -EAGAIN)
+			goto out;
+		release_sock(sk);
+		timeo = sock_rcvtimeo(sk, flags & MSG_DONTWAIT);
+		while (timeo && !__skb_wait_for_more_packets(sk, sk_queue, &err,
+							     &timeo, last)) {
+			skb = __skb_try_recv_datagram(sk, sk_queue, flags, &off,
+						      &err, &last);
+			if (skb)
+				break;
+
+			if (err != -EAGAIN)
+				goto done;
+		}
+		if (!skb)
+			goto done;
+		lock_sock(sk);
+	}
 
 	if (!sk_to_ax25(sk)->pidincl)
 		skb_pull(skb, 1);		/* Remove PID */
@@ -1719,6 +1747,7 @@ static int ax25_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
 out:
 	release_sock(sk);
 
+done:
 	return err;
 }