Commit f3d82d0c authored by Johan Hedberg's avatar Johan Hedberg Committed by Marcel Holtmann
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Bluetooth: Move identity address update behind a workqueue 



The identity address update of all channels for an l2cap_conn needs to
take the lock for each channel, i.e. it's safest to do this by a
separate workqueue callback.

Previously this was partially solved by moving the entire SMP key
distribution behind a workqueue. However, if we want SMP context locking
to be correct and safe we should always use the l2cap_chan lock when
accessing it, meaning even smp_distribute_keys needs to take that lock
which would once again create a dead lock when updating the identity
address.

The simplest way to solve this is to have l2cap_conn manage the deferred
work which is what this patch does. A subsequent patch will remove the
now unnecessary SMP key distribution work struct.

Signed-off-by: default avatarJohan Hedberg <johan.hedberg@intel.com>
Signed-off-by: default avatarMarcel Holtmann <marcel@holtmann.org>
parent 84bc0db5

include/net/bluetooth/l2cap.h

+2 −1
Original line number Diff line number Diff line
@@ -633,6 +633,8 @@ struct l2cap_conn { 
	struct sk_buff_head	pending_rx;

	struct work_struct	pending_rx_work;



	struct work_struct	id_addr_update_work;



	__u8			disc_reason;



	struct l2cap_chan	*smp;
@@ -937,7 +939,6 @@ int l2cap_ertm_init(struct l2cap_chan *chan); 
void l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan);

void __l2cap_chan_add(struct l2cap_conn *conn, struct l2cap_chan *chan);

void l2cap_chan_del(struct l2cap_chan *chan, int err);

void l2cap_conn_update_id_addr(struct hci_conn *hcon);

void l2cap_send_conn_req(struct l2cap_chan *chan);

void l2cap_move_start(struct l2cap_chan *chan);

void l2cap_logical_cfm(struct l2cap_chan *chan, struct hci_chan *hchan,

net/bluetooth/l2cap_core.c

+8 −2
Original line number Diff line number Diff line
@@ -631,9 +631,11 @@ void l2cap_chan_del(struct l2cap_chan *chan, int err) 
}

EXPORT_SYMBOL_GPL(l2cap_chan_del);



void l2cap_conn_update_id_addr(struct hci_conn *hcon)

static void l2cap_conn_update_id_addr(struct work_struct *work)

{

	struct l2cap_conn *conn = hcon->l2cap_data;

	struct l2cap_conn *conn = container_of(work, struct l2cap_conn,

					       id_addr_update_work);

	struct hci_conn *hcon = conn->hcon;

	struct l2cap_chan *chan;



	mutex_lock(&conn->chan_lock);
@@ -1635,6 +1637,9 @@ static void l2cap_conn_del(struct hci_conn *hcon, int err) 
	if (work_pending(&conn->pending_rx_work))

		cancel_work_sync(&conn->pending_rx_work);



	if (work_pending(&conn->id_addr_update_work))

		cancel_work_sync(&conn->id_addr_update_work);



	l2cap_unregister_all_users(conn);



	/* Force the connection to be immediately dropped */
@@ -6927,6 +6932,7 @@ static struct l2cap_conn *l2cap_conn_add(struct hci_conn *hcon) 


	skb_queue_head_init(&conn->pending_rx);

	INIT_WORK(&conn->pending_rx_work, process_pending_rx);

	INIT_WORK(&conn->id_addr_update_work, l2cap_conn_update_id_addr);



	conn->disc_reason = HCI_ERROR_REMOTE_USER_TERM;

net/bluetooth/smp.c

+1 −1
Original line number Diff line number Diff line
@@ -654,7 +654,7 @@ static void smp_notify_keys(struct l2cap_conn *conn) 
		 */

		bacpy(&hcon->dst, &smp->remote_irk->bdaddr);

		hcon->dst_type = smp->remote_irk->addr_type;

		l2cap_conn_update_id_addr(hcon);

		queue_work(hdev->workqueue, &conn->id_addr_update_work);



		/* When receiving an indentity resolving key for

		 * a remote device that does not use a resolvable

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