Merge v7.1.5linux-rolling-stable

Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

12 files changed, 222 insertions, 156 deletions

diff --git a/net/bluetooth/6lowpan.c b/net/bluetooth/6lowpan.c
index 4dbbc44a950d..d504a363a30f 100644
--- a/net/bluetooth/6lowpan.c
+++ b/net/bluetooth/6lowpan.c
@@ -632,7 +632,7 @@ static struct l2cap_chan *chan_create(void)
 	if (!chan)
 		return NULL;
 
-	l2cap_chan_set_defaults(chan);
+	l2cap_chan_set_defaults(chan, NULL);
 
 	chan->chan_type = L2CAP_CHAN_CONN_ORIENTED;
 	chan->mode = L2CAP_MODE_LE_FLOWCTL;
@@ -745,19 +745,24 @@ static inline void chan_ready_cb(struct l2cap_chan *chan)
 	ifup(dev->netdev);
 }
 
-static inline struct l2cap_chan *chan_new_conn_cb(struct l2cap_chan *pchan)
+static void unregister_dev(struct lowpan_btle_dev *dev)
 {
-	struct l2cap_chan *chan;
-
-	chan = chan_create();
-	if (!chan)
-		return NULL;
-
-	chan->ops = pchan->ops;
-
-	BT_DBG("chan %p pchan %p", chan, pchan);
-
-	return chan;
+	struct hci_dev *hdev = READ_ONCE(dev->hdev);
+
+	/* If netdev holds last reference to hci_dev (its parent device), this
+	 * leads to theoretical cyclic locking on lowpan_unregister_netdev:
+	 *
+	 * rtnl_lock -> put_device(parent) -> hci_release_dev ->
+	 * destroy_workqueue -> hci_rx_work -> l2cap_recv_acldata ->
+	 * chan_ready_cb -> ifup -> rtnl_lock
+	 *
+	 * However, hci_rx_work is disabled in hci_unregister_dev, so this
+	 * should not occur. Make lockdep happy by postponing hdev release after
+	 * netdev put.
+	 */
+	hci_dev_hold(hdev);
+	lowpan_unregister_netdev(dev->netdev);
+	hci_dev_put(hdev);
 }
 
 static void delete_netdev(struct work_struct *work)
@@ -766,7 +771,7 @@ static void delete_netdev(struct work_struct *work)
 						     struct lowpan_btle_dev,
 						     delete_netdev);
 
-	lowpan_unregister_netdev(entry->netdev);
+	unregister_dev(entry);
 
 	/* The entry pointer is deleted by the netdev destructor. */
 }
@@ -869,7 +874,6 @@ static long chan_get_sndtimeo_cb(struct l2cap_chan *chan)
 
 static const struct l2cap_ops bt_6lowpan_chan_ops = {
 	.name			= "L2CAP 6LoWPAN channel",
-	.new_connection		= chan_new_conn_cb,
 	.recv			= chan_recv_cb,
 	.close			= chan_close_cb,
 	.state_change		= chan_state_change_cb,
@@ -997,16 +1001,19 @@ static int get_l2cap_conn(char *buf, bdaddr_t *addr, u8 *addr_type,
 
 	hci_dev_lock(hdev);
 	hcon = hci_conn_hash_lookup_le(hdev, addr, le_addr_type);
-	hci_dev_unlock(hdev);
-	hci_dev_put(hdev);
-
-	if (!hcon)
+	if (!hcon) {
+		hci_dev_unlock(hdev);
+		hci_dev_put(hdev);
 		return -ENOENT;
+	}
 
-	*conn = (struct l2cap_conn *)hcon->l2cap_data;
+	*conn = l2cap_conn_hold_unless_zero(hcon->l2cap_data);
 
 	BT_DBG("conn %p dst %pMR type %u", *conn, &hcon->dst, hcon->dst_type);
 
+	hci_dev_unlock(hdev);
+	hci_dev_put(hdev);
+
 	return 0;
 }
 
@@ -1061,23 +1068,15 @@ done:
 	} while (nchans);
 }
 
-struct set_enable {
-	struct work_struct work;
-	bool flag;
-};
-
-static void do_enable_set(struct work_struct *work)
+static void do_enable_set(bool flag)
 {
-	struct set_enable *set_enable = container_of(work,
-						     struct set_enable, work);
-
-	if (!set_enable->flag || enable_6lowpan != set_enable->flag)
+	if (!flag || enable_6lowpan != flag)
 		/* Disconnect existing connections if 6lowpan is
 		 * disabled
 		 */
 		disconnect_all_peers();
 
-	enable_6lowpan = set_enable->flag;
+	enable_6lowpan = flag;
 
 	mutex_lock(&set_lock);
 	if (listen_chan) {
@@ -1089,22 +1088,11 @@ static void do_enable_set(struct work_struct *work)
 
 	listen_chan = bt_6lowpan_listen();
 	mutex_unlock(&set_lock);
-
-	kfree(set_enable);
 }
 
 static int lowpan_enable_set(void *data, u64 val)
 {
-	struct set_enable *set_enable;
-
-	set_enable = kzalloc_obj(*set_enable);
-	if (!set_enable)
-		return -ENOMEM;
-
-	set_enable->flag = !!val;
-	INIT_WORK(&set_enable->work, do_enable_set);
-
-	schedule_work(&set_enable->work);
+	do_enable_set(!!val);
 
 	return 0;
 }
@@ -1153,18 +1141,22 @@ static ssize_t lowpan_control_write(struct file *fp,
 		if (conn) {
 			struct lowpan_peer *peer;
 
-			if (!is_bt_6lowpan(conn->hcon))
+			if (!is_bt_6lowpan(conn->hcon)) {
+				l2cap_conn_put(conn);
 				return -EINVAL;
+			}
 
 			peer = lookup_peer(conn);
 			if (peer) {
 				BT_DBG("6LoWPAN connection already exists");
+				l2cap_conn_put(conn);
 				return -EALREADY;
 			}
 
 			BT_DBG("conn %p dst %pMR type %d user %u", conn,
 			       &conn->hcon->dst, conn->hcon->dst_type,
 			       addr_type);
+			l2cap_conn_put(conn);
 		}
 
 		ret = bt_6lowpan_connect(&addr, addr_type);
@@ -1180,6 +1172,8 @@ static ssize_t lowpan_control_write(struct file *fp,
 			return ret;
 
 		ret = bt_6lowpan_disconnect(conn, addr_type);
+		if (conn)
+			l2cap_conn_put(conn);
 		if (ret < 0)
 			return ret;
 
@@ -1240,6 +1234,7 @@ static void disconnect_devices(void)
 			break;
 
 		new_dev->netdev = entry->netdev;
+		new_dev->hdev = entry->hdev;
 		INIT_LIST_HEAD(&new_dev->list);
 
 		list_add_rcu(&new_dev->list, &devices);
@@ -1251,7 +1246,7 @@ static void disconnect_devices(void)
 		ifdown(entry->netdev);
 		BT_DBG("Unregistering netdev %s %p",
 		       entry->netdev->name, entry->netdev);
-		lowpan_unregister_netdev(entry->netdev);
+		unregister_dev(entry);
 		kfree(entry);
 	}
 }
diff --git a/net/bluetooth/eir.c b/net/bluetooth/eir.c
index 3f72111ba651..1de5f9df6eec 100644
--- a/net/bluetooth/eir.c
+++ b/net/bluetooth/eir.c
@@ -283,10 +283,12 @@ u8 eir_create_adv_data(struct hci_dev *hdev, u8 instance, u8 *ptr, u8 size)
 		if (!flags)
 			flags |= mgmt_get_adv_discov_flags(hdev);
 
-		/* If flags would still be empty, then there is no need to
-		 * include the "Flags" AD field".
+		/* Only add the "Flags" if it fits together with the instance
+		 * advertising data; drop it rather than overflow the buffer.
 		 */
-		if (flags && (ad_len + eir_precalc_len(1) <= size)) {
+		if (flags &&
+		    (ad_len + eir_precalc_len(1) +
+		     (adv ? adv->adv_data_len : 0) <= size)) {
 			ptr[0] = 0x02;
 			ptr[1] = EIR_FLAGS;
 			ptr[2] = flags;
diff --git a/net/bluetooth/hci_codec.c b/net/bluetooth/hci_codec.c
index 3cc135bb1d30..5bc5003c387c 100644
--- a/net/bluetooth/hci_codec.c
+++ b/net/bluetooth/hci_codec.c
@@ -100,7 +100,7 @@ static void hci_read_codec_capabilities(struct hci_dev *hdev, __u8 transport,
 				caps = (void *)skb->data;
 				if (skb->len < sizeof(*caps))
 					goto error;
-				if (skb->len < caps->len)
+				if (skb->len < sizeof(caps->len) + caps->len)
 					goto error;
 				len += sizeof(caps->len) + caps->len;
 				skb_pull(skb,  sizeof(caps->len) + caps->len);
diff --git a/net/bluetooth/hci_core.c b/net/bluetooth/hci_core.c
index 28d7929dc593..1cbc666527c5 100644
--- a/net/bluetooth/hci_core.c
+++ b/net/bluetooth/hci_core.c
@@ -2671,6 +2671,8 @@ void hci_unregister_dev(struct hci_dev *hdev)
 	disable_work_sync(&hdev->tx_work);
 	disable_work_sync(&hdev->power_on);
 	disable_work_sync(&hdev->error_reset);
+	disable_delayed_work_sync(&hdev->cmd_timer);
+	disable_delayed_work_sync(&hdev->ncmd_timer);
 
 	hci_cmd_sync_clear(hdev);
 
diff --git a/net/bluetooth/hci_event.c b/net/bluetooth/hci_event.c
index eea2f810aafa..1cd5f97daafe 100644
--- a/net/bluetooth/hci_event.c
+++ b/net/bluetooth/hci_event.c
@@ -1769,6 +1769,13 @@ static void le_set_scan_enable_complete(struct hci_dev *hdev, u8 enable)
 
 		hci_dev_clear_flag(hdev, HCI_LE_SCAN);
 
+		if (hdev->discovery.type == DISCOV_TYPE_INTERLEAVED &&
+		    hci_test_quirk(hdev, HCI_QUIRK_SIMULTANEOUS_DISCOVERY) &&
+		    !test_bit(HCI_INQUIRY, &hdev->flags) &&
+		    hdev->discovery.state == DISCOVERY_FINDING) {
+			hci_discovery_set_state(hdev, DISCOVERY_STOPPED);
+		}
+
 		/* The HCI_LE_SCAN_INTERRUPTED flag indicates that we
 		 * interrupted scanning due to a connect request. Mark
 		 * therefore discovery as stopped.
diff --git a/net/bluetooth/iso.c b/net/bluetooth/iso.c
index 7186e8d88c75..1d5ce87e6496 100644
--- a/net/bluetooth/iso.c
+++ b/net/bluetooth/iso.c
@@ -2539,7 +2539,7 @@ int iso_recv(struct hci_dev *hdev, u16 handle, struct sk_buff *skb, u16 flags)
 	switch (pb) {
 	case ISO_START:
 	case ISO_SINGLE:
-		if (conn->rx_len) {
+		if (conn->rx_skb || conn->rx_len) {
 			BT_ERR("Unexpected start frame (len %d)", skb->len);
 			kfree_skb(conn->rx_skb);
 			conn->rx_skb = NULL;
@@ -2620,12 +2620,14 @@ int iso_recv(struct hci_dev *hdev, u16 handle, struct sk_buff *skb, u16 flags)
 		break;
 
 	case ISO_CONT:
-		BT_DBG("Cont: frag len %d (expecting %d)", skb->len,
+	case ISO_END:
+		BT_DBG("%s: frag len %d (expecting %d)",
+		       (pb == ISO_END) ? "End" : "Cont", skb->len,
 		       conn->rx_len);
 
-		if (!conn->rx_len) {
-			BT_ERR("Unexpected continuation frame (len %d)",
-			       skb->len);
+		if (!conn->rx_skb) {
+			BT_ERR("Unexpected ISO %s frame (len %d)",
+			       (pb == ISO_END) ? "End" : "Cont", skb->len);
 			goto drop;
 		}
 
@@ -2641,17 +2643,9 @@ int iso_recv(struct hci_dev *hdev, u16 handle, struct sk_buff *skb, u16 flags)
 		skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, skb->len),
 					  skb->len);
 		conn->rx_len -= skb->len;
-		break;
 
-	case ISO_END:
-		if (!conn->rx_len) {
-			BT_ERR("Unexpected end frame (len %d)", skb->len);
-			goto drop;
-		}
-
-		skb_copy_from_linear_data(skb, skb_put(conn->rx_skb, skb->len),
-					  skb->len);
-		conn->rx_len -= skb->len;
+		if (pb == ISO_CONT)
+			break;
 
 		if (!conn->rx_len) {
 			struct sk_buff *rx_skb = conn->rx_skb;
@@ -2662,6 +2656,13 @@ int iso_recv(struct hci_dev *hdev, u16 handle, struct sk_buff *skb, u16 flags)
 			 */
 			conn->rx_skb = NULL;
 			iso_recv_frame(conn, rx_skb);
+		} else {
+			BT_ERR("ISO fragment incomplete (len %d, expected %d)",
+			       skb->len, conn->rx_len);
+			kfree_skb(conn->rx_skb);
+			conn->rx_skb = NULL;
+			conn->rx_len = 0;
+			goto drop;
 		}
 		break;
 	}
diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c
index 32f0c8b73b17..189085000c73 100644
--- a/net/bluetooth/l2cap_core.c
+++ b/net/bluetooth/l2cap_core.c
@@ -525,7 +525,10 @@ void l2cap_chan_put(struct l2cap_chan *c)
 }
 EXPORT_SYMBOL_GPL(l2cap_chan_put);
 
-void l2cap_chan_set_defaults(struct l2cap_chan *chan)
+/* Initialise @chan with default values, inheriting from the parent channel
+ * @pchan when it is given.
+ */
+void l2cap_chan_set_defaults(struct l2cap_chan *chan, struct l2cap_chan *pchan)
 {
 	chan->fcs  = L2CAP_FCS_CRC16;
 	chan->max_tx = L2CAP_DEFAULT_MAX_TX;
@@ -539,6 +542,31 @@ void l2cap_chan_set_defaults(struct l2cap_chan *chan)
 	chan->retrans_timeout = L2CAP_DEFAULT_RETRANS_TO;
 	chan->monitor_timeout = L2CAP_DEFAULT_MONITOR_TO;
 
+	if (pchan) {
+		BT_DBG("chan %p pchan %p", chan, pchan);
+
+		chan->chan_type = pchan->chan_type;
+		chan->imtu = pchan->imtu;
+		chan->omtu = pchan->omtu;
+		chan->mode = pchan->mode;
+		chan->fcs = pchan->fcs;
+		chan->max_tx = pchan->max_tx;
+		chan->tx_win = pchan->tx_win;
+		chan->tx_win_max = pchan->tx_win_max;
+		chan->sec_level = pchan->sec_level;
+		chan->conf_state = pchan->conf_state;
+		chan->flags = pchan->flags;
+		chan->tx_credits = pchan->tx_credits;
+		chan->rx_credits = pchan->rx_credits;
+
+		if (chan->chan_type == L2CAP_CHAN_FIXED) {
+			chan->scid = pchan->scid;
+			chan->dcid = pchan->scid;
+		}
+
+		return;
+	}
+
 	chan->conf_state = 0;
 	set_bit(CONF_NOT_COMPLETE, &chan->conf_state);
 
@@ -4027,6 +4055,38 @@ static inline int l2cap_command_rej(struct l2cap_conn *conn,
 	return 0;
 }
 
+/* Allocate and initialise a channel for an incoming connection.
+ *
+ * The channel inherits its configuration from @pchan and is linked into @conn
+ * before ->new_connection() runs, so the conn list reference keeps it alive if
+ * the callback exposes it (e.g. via the socket accept queue) before this
+ * returns. The l2cap_chan_create() reference is taken over by the subsystem on
+ * success and dropped here on failure.
+ */
+static struct l2cap_chan *l2cap_new_connection(struct l2cap_conn *conn,
+					       struct l2cap_chan *pchan)
+{
+	struct l2cap_chan *chan;
+
+	chan = l2cap_chan_create();
+	if (!chan)
+		return NULL;
+
+	l2cap_chan_set_defaults(chan, pchan);
+	chan->ops = pchan->ops;
+
+	__l2cap_chan_add(conn, chan);
+
+	if (pchan->ops->new_connection &&
+	    pchan->ops->new_connection(pchan, chan) < 0) {
+		l2cap_chan_del(chan, 0);
+		l2cap_chan_put(chan);
+		return NULL;
+	}
+
+	return chan;
+}
+
 static void l2cap_connect(struct l2cap_conn *conn, struct l2cap_cmd_hdr *cmd,
 			  u8 *data, u8 rsp_code)
 {
@@ -4073,7 +4133,7 @@ static void l2cap_connect(struct l2cap_conn *conn, struct l2cap_cmd_hdr *cmd,
 		goto response;
 	}
 
-	chan = pchan->ops->new_connection(pchan);
+	chan = l2cap_new_connection(conn, pchan);
 	if (!chan)
 		goto response;
 
@@ -4091,8 +4151,6 @@ static void l2cap_connect(struct l2cap_conn *conn, struct l2cap_cmd_hdr *cmd,
 	chan->psm  = psm;
 	chan->dcid = scid;
 
-	__l2cap_chan_add(conn, chan);
-
 	dcid = chan->scid;
 
 	__set_chan_timer(chan, chan->ops->get_sndtimeo(chan));
@@ -4824,6 +4882,7 @@ static void l2cap_put_ident(struct l2cap_conn *conn, u8 code, u8 id)
 	case L2CAP_ECHO_RSP:
 	case L2CAP_INFO_RSP:
 	case L2CAP_CONN_PARAM_UPDATE_RSP:
+	case L2CAP_LE_CONN_RSP:
 	case L2CAP_ECRED_CONN_RSP:
 	case L2CAP_ECRED_RECONF_RSP:
 		/* First do a lookup since the remote may send bogus ids that
@@ -4975,7 +5034,7 @@ static int l2cap_le_connect_req(struct l2cap_conn *conn,
 		goto response_unlock;
 	}
 
-	chan = pchan->ops->new_connection(pchan);
+	chan = l2cap_new_connection(conn, pchan);
 	if (!chan) {
 		result = L2CAP_CR_LE_NO_MEM;
 		goto response_unlock;
@@ -4990,8 +5049,6 @@ static int l2cap_le_connect_req(struct l2cap_conn *conn,
 	chan->omtu = mtu;
 	chan->remote_mps = mps;
 
-	__l2cap_chan_add(conn, chan);
-
 	l2cap_le_flowctl_init(chan, __le16_to_cpu(req->credits));
 
 	dcid = chan->scid;
@@ -5199,7 +5256,7 @@ static inline int l2cap_ecred_conn_req(struct l2cap_conn *conn,
 			continue;
 		}
 
-		chan = pchan->ops->new_connection(pchan);
+		chan = l2cap_new_connection(conn, pchan);
 		if (!chan) {
 			result = L2CAP_CR_LE_NO_MEM;
 			continue;
@@ -5214,8 +5271,6 @@ static inline int l2cap_ecred_conn_req(struct l2cap_conn *conn,
 		chan->omtu = mtu;
 		chan->remote_mps = mps;
 
-		__l2cap_chan_add(conn, chan);
-
 		l2cap_ecred_init(chan, __le16_to_cpu(req->credits));
 
 		/* Init response */
@@ -6721,6 +6776,7 @@ static void l2cap_chan_le_send_credits(struct l2cap_chan *chan)
 	struct l2cap_conn *conn = chan->conn;
 	struct l2cap_le_credits pkt;
 	u16 return_credits = l2cap_le_rx_credits(chan);
+	int ident;
 
 	if (chan->mode != L2CAP_MODE_LE_FLOWCTL &&
 	    chan->mode != L2CAP_MODE_EXT_FLOWCTL)
@@ -6738,9 +6794,18 @@ static void l2cap_chan_le_send_credits(struct l2cap_chan *chan)
 	pkt.cid     = cpu_to_le16(chan->scid);
 	pkt.credits = cpu_to_le16(return_credits);
 
-	chan->ident = l2cap_get_ident(conn);
+	ident = l2cap_get_ident(conn);
+
+	l2cap_send_cmd(conn, ident, L2CAP_LE_CREDITS, sizeof(pkt), &pkt);
 
-	l2cap_send_cmd(conn, chan->ident, L2CAP_LE_CREDITS, sizeof(pkt), &pkt);
+	/* L2CAP_LE_CREDITS has no response so the ident is never released by
+	 * l2cap_put_ident() - release it right away, otherwise the tx_ida
+	 * range is exhausted after 254 packets and from then on credits are
+	 * sent with the invalid ident 0, which some remote stacks ignore,
+	 * stalling the channel.
+	 */
+	if (ident > 0)
+		ida_free(&conn->tx_ida, ident);
 }
 
 void l2cap_chan_rx_avail(struct l2cap_chan *chan, ssize_t rx_avail)
@@ -7490,14 +7555,12 @@ static void l2cap_connect_cfm(struct hci_conn *hcon, u8 status)
 			goto next;
 
 		l2cap_chan_lock(pchan);
-		chan = pchan->ops->new_connection(pchan);
+		chan = l2cap_new_connection(conn, pchan);
 		if (chan) {
 			bacpy(&chan->src, &hcon->src);
 			bacpy(&chan->dst, &hcon->dst);
 			chan->src_type = bdaddr_src_type(hcon);
 			chan->dst_type = dst_type;
-
-			__l2cap_chan_add(conn, chan);
 		}
 
 		l2cap_chan_unlock(pchan);
@@ -7714,6 +7777,7 @@ struct l2cap_conn *l2cap_conn_hold_unless_zero(struct l2cap_conn *c)
 
 	return c;
 }
+EXPORT_SYMBOL(l2cap_conn_hold_unless_zero);
 
 int l2cap_recv_acldata(struct hci_dev *hdev, u16 handle,
 		       struct sk_buff *skb, u16 flags)
diff --git a/net/bluetooth/l2cap_sock.c b/net/bluetooth/l2cap_sock.c
index 1e93de155987..d8cbe2784437 100644
--- a/net/bluetooth/l2cap_sock.c
+++ b/net/bluetooth/l2cap_sock.c
@@ -45,7 +45,8 @@ static struct bt_sock_list l2cap_sk_list = {
 static const struct proto_ops l2cap_sock_ops;
 static void l2cap_sock_init(struct sock *sk, struct sock *parent);
 static struct sock *l2cap_sock_alloc(struct net *net, struct socket *sock,
-				     int proto, gfp_t prio, int kern);
+				     int proto, gfp_t prio, int kern,
+				     struct l2cap_chan *chan);
 static void l2cap_sock_cleanup_listen(struct sock *parent);
 
 bool l2cap_is_socket(struct socket *sock)
@@ -1274,6 +1275,23 @@ done:
 	return err;
 }
 
+/* Release the sock's ref on chan and clear the pointer so that the ref is
+ * dropped exactly once even if both l2cap_sock_kill() and
+ * l2cap_sock_destruct() run. Setting chan->data to NULL first stops any other
+ * task from dereferencing the now-dead sock pointer.
+ */
+static void l2cap_sock_put_chan(struct sock *sk)
+{
+	struct l2cap_chan *chan = l2cap_pi(sk)->chan;
+
+	if (!chan)
+		return;
+
+	chan->data = NULL;
+	l2cap_pi(sk)->chan = NULL;
+	l2cap_chan_put(chan);
+}
+
 /* Kill socket (only if zapped and orphan)
  * Must be called on unlocked socket, with l2cap channel lock.
  */
@@ -1284,13 +1302,9 @@ static void l2cap_sock_kill(struct sock *sk)
 
 	BT_DBG("sk %p state %s", sk, state_to_string(sk->sk_state));
 
-	/* Sock is dead, so set chan data to NULL, avoid other task use invalid
-	 * sock pointer.
-	 */
-	l2cap_pi(sk)->chan->data = NULL;
-	/* Kill poor orphan */
+	l2cap_sock_put_chan(sk);
 
-	l2cap_chan_put(l2cap_pi(sk)->chan);
+	/* Kill poor orphan */
 	sock_set_flag(sk, SOCK_DEAD);
 	sock_put(sk);
 }
@@ -1533,12 +1547,13 @@ static void l2cap_sock_cleanup_listen(struct sock *parent)
 	}
 }
 
-static struct l2cap_chan *l2cap_sock_new_connection_cb(struct l2cap_chan *chan)
+static int l2cap_sock_new_connection_cb(struct l2cap_chan *chan,
+					struct l2cap_chan *new_chan)
 {
 	struct sock *sk, *parent = chan->data;
 
 	if (!parent)
-		return NULL;
+		return -EINVAL;
 
 	lock_sock(parent);
 
@@ -1546,25 +1561,28 @@ static struct l2cap_chan *l2cap_sock_new_connection_cb(struct l2cap_chan *chan)
 	if (sk_acceptq_is_full(parent)) {
 		BT_DBG("backlog full %d", parent->sk_ack_backlog);
 		release_sock(parent);
-		return NULL;
+		return -ENOBUFS;
 	}
 
 	sk = l2cap_sock_alloc(sock_net(parent), NULL, BTPROTO_L2CAP,
-			      GFP_ATOMIC, 0);
+			      GFP_ATOMIC, 0, new_chan);
 	if (!sk) {
 		release_sock(parent);
-		return NULL;
-        }
+		return -ENOMEM;
+	}
 
 	bt_sock_reclassify_lock(sk, BTPROTO_L2CAP);
 
 	l2cap_sock_init(sk, parent);
 
+	/* The conn list reference taken by l2cap_new_connection() keeps new_chan
+	 * alive once release_sock() lets another task free this socket.
+	 */
 	bt_accept_enqueue(parent, sk, false);
 
 	release_sock(parent);
 
-	return l2cap_pi(sk)->chan;
+	return 0;
 }
 
 static int l2cap_sock_recv_cb(struct l2cap_chan *chan, struct sk_buff *skb)
@@ -1861,10 +1879,7 @@ static void l2cap_sock_destruct(struct sock *sk)
 
 	BT_DBG("sk %p", sk);
 
-	if (l2cap_pi(sk)->chan) {
-		l2cap_pi(sk)->chan->data = NULL;
-		l2cap_chan_put(l2cap_pi(sk)->chan);
-	}
+	l2cap_sock_put_chan(sk);
 
 	list_for_each_entry_safe(rx_busy, next, &l2cap_pi(sk)->rx_busy, list) {
 		kfree_skb(rx_busy->skb);
@@ -1897,30 +1912,12 @@ static void l2cap_sock_init(struct sock *sk, struct sock *parent)
 	BT_DBG("sk %p", sk);
 
 	if (parent) {
-		struct l2cap_chan *pchan = l2cap_pi(parent)->chan;
-
 		sk->sk_type = parent->sk_type;
 		bt_sk(sk)->flags = bt_sk(parent)->flags;
 
-		chan->chan_type = pchan->chan_type;
-		chan->imtu = pchan->imtu;
-		chan->omtu = pchan->omtu;
-		chan->conf_state = pchan->conf_state;
-		chan->mode = pchan->mode;
-		chan->fcs  = pchan->fcs;
-		chan->max_tx = pchan->max_tx;
-		chan->tx_win = pchan->tx_win;
-		chan->tx_win_max = pchan->tx_win_max;
-		chan->sec_level = pchan->sec_level;
-		chan->flags = pchan->flags;
-		chan->tx_credits = pchan->tx_credits;
-		chan->rx_credits = pchan->rx_credits;
-
-		if (chan->chan_type == L2CAP_CHAN_FIXED) {
-			chan->scid = pchan->scid;
-			chan->dcid = pchan->scid;
-		}
-
+		/* Channel configuration is inherited from the parent by
+		 * l2cap_new_connection().
+		 */
 		security_sk_clone(parent, sk);
 	} else {
 		switch (sk->sk_type) {
@@ -1946,7 +1943,7 @@ static void l2cap_sock_init(struct sock *sk, struct sock *parent)
 			chan->mode = L2CAP_MODE_BASIC;
 		}
 
-		l2cap_chan_set_defaults(chan);
+		l2cap_chan_set_defaults(chan, NULL);
 	}
 
 	/* Default config options */
@@ -1965,10 +1962,10 @@ static struct proto l2cap_proto = {
 };
 
 static struct sock *l2cap_sock_alloc(struct net *net, struct socket *sock,
-				     int proto, gfp_t prio, int kern)
+				     int proto, gfp_t prio, int kern,
+				     struct l2cap_chan *chan)
 {
 	struct sock *sk;
-	struct l2cap_chan *chan;
 
 	sk = bt_sock_alloc(net, sock, &l2cap_proto, proto, prio, kern);
 	if (!sk)
@@ -1979,16 +1976,7 @@ static struct sock *l2cap_sock_alloc(struct net *net, struct socket *sock,
 
 	INIT_LIST_HEAD(&l2cap_pi(sk)->rx_busy);
 
-	chan = l2cap_chan_create();
-	if (!chan) {
-		sk_free(sk);
-		if (sock)
-			sock->sk = NULL;
-		return NULL;
-	}
-
-	l2cap_chan_hold(chan);
-
+	/* The sock takes ownership of the caller's reference on chan. */
 	l2cap_pi(sk)->chan = chan;
 
 	return sk;
@@ -1998,6 +1986,7 @@ static int l2cap_sock_create(struct net *net, struct socket *sock, int protocol,
 			     int kern)
 {
 	struct sock *sk;
+	struct l2cap_chan *chan;
 
 	BT_DBG("sock %p", sock);
 
@@ -2012,10 +2001,16 @@ static int l2cap_sock_create(struct net *net, struct socket *sock, int protocol,
 
 	sock->ops = &l2cap_sock_ops;
 
-	sk = l2cap_sock_alloc(net, sock, protocol, GFP_ATOMIC, kern);
-	if (!sk)
+	chan = l2cap_chan_create();
+	if (!chan)
 		return -ENOMEM;
 
+	sk = l2cap_sock_alloc(net, sock, protocol, GFP_ATOMIC, kern, chan);
+	if (!sk) {
+		l2cap_chan_put(chan);
+		return -ENOMEM;
+	}
+
 	l2cap_sock_init(sk, NULL);
 	bt_sock_link(&l2cap_sk_list, sk);
 	return 0;
diff --git a/net/bluetooth/mgmt.c b/net/bluetooth/mgmt.c
index 7c164a17ef59..e8544194a524 100644
--- a/net/bluetooth/mgmt.c
+++ b/net/bluetooth/mgmt.c
@@ -5378,6 +5378,8 @@ static void mgmt_add_adv_patterns_monitor_complete(struct hci_dev *hdev,
 		if (monitor->state == ADV_MONITOR_STATE_NOT_REGISTERED)
 			monitor->state = ADV_MONITOR_STATE_REGISTERED;
 		hci_update_passive_scan(hdev);
+	} else {
+		hci_free_adv_monitor(hdev, monitor);
 	}
 
 	mgmt_cmd_complete(cmd->sk, cmd->hdev->id, cmd->opcode,
diff --git a/net/bluetooth/msft.c b/net/bluetooth/msft.c
index 2f008167cbaa..d7badce8746c 100644
--- a/net/bluetooth/msft.c
+++ b/net/bluetooth/msft.c
@@ -291,7 +291,7 @@ static int msft_le_monitor_advertisement_cb(struct hci_dev *hdev, u16 opcode,
 	monitor->state = ADV_MONITOR_STATE_OFFLOADED;
 
 unlock:
-	if (status)
+	if (status && msft->resuming)
 		hci_free_adv_monitor(hdev, monitor);
 
 	hci_dev_unlock(hdev);
diff --git a/net/bluetooth/sco.c b/net/bluetooth/sco.c
index 140869e5b2df..b2c51f3ebc40 100644
--- a/net/bluetooth/sco.c
+++ b/net/bluetooth/sco.c
@@ -572,10 +572,23 @@ static void __sco_sock_close(struct sock *sk)
 /* Must be called on unlocked socket. */
 static void sco_sock_close(struct sock *sk)
 {
+	struct sco_conn *conn;
+
+	lock_sock(sk);
+	conn = sco_pi(sk)->conn;
+	if (conn)
+		sco_conn_hold(conn);
+	release_sock(sk);
+
+	if (conn)
+		disable_delayed_work_sync(&conn->timeout_work);
+
 	lock_sock(sk);
-	sco_sock_clear_timer(sk);
 	__sco_sock_close(sk);
 	release_sock(sk);
+
+	if (conn)
+		sco_conn_put(conn);
 }
 
 static void sco_sock_init(struct sock *sk, struct sock *parent)
diff --git a/net/bluetooth/smp.c b/net/bluetooth/smp.c
index 98f1da4f5f55..4787f8cd29e4 100644
--- a/net/bluetooth/smp.c
+++ b/net/bluetooth/smp.c
@@ -3234,34 +3234,19 @@ static const struct l2cap_ops smp_chan_ops = {
 	.get_sndtimeo		= l2cap_chan_no_get_sndtimeo,
 };
 
-static inline struct l2cap_chan *smp_new_conn_cb(struct l2cap_chan *pchan)
+static inline int smp_new_conn_cb(struct l2cap_chan *chan,
+				  struct l2cap_chan *new_chan)
 {
-	struct l2cap_chan *chan;
-
-	BT_DBG("pchan %p", pchan);
-
-	chan = l2cap_chan_create();
-	if (!chan)
-		return NULL;
-
-	chan->chan_type	= pchan->chan_type;
-	chan->ops	= &smp_chan_ops;
-	chan->scid	= pchan->scid;
-	chan->dcid	= chan->scid;
-	chan->imtu	= pchan->imtu;
-	chan->omtu	= pchan->omtu;
-	chan->mode	= pchan->mode;
+	new_chan->ops = &smp_chan_ops;
 
 	/* Other L2CAP channels may request SMP routines in order to
 	 * change the security level. This means that the SMP channel
 	 * lock must be considered in its own category to avoid lockdep
 	 * warnings.
 	 */
-	atomic_set(&chan->nesting, L2CAP_NESTING_SMP);
-
-	BT_DBG("created chan %p", chan);
+	atomic_set(&new_chan->nesting, L2CAP_NESTING_SMP);
 
-	return chan;
+	return 0;
 }
 
 static const struct l2cap_ops smp_root_chan_ops = {
@@ -3332,7 +3317,7 @@ create_chan:
 
 	l2cap_add_scid(chan, cid);
 
-	l2cap_chan_set_defaults(chan);
+	l2cap_chan_set_defaults(chan, NULL);
 
 	if (cid == L2CAP_CID_SMP) {
 		u8 bdaddr_type;