Bluetooth: Always call smp_distribute_keys() from a workqueue

The smp_distribute_keys() function calls smp_notify_keys() which in turn
calls l2cap_conn_update_id_addr(). The l2cap_conn_update_id_addr()
function will iterate through all L2CAP channels for the respective
connection: lock the channel, update the address information and unlock
the channel.

Since SMP is now using l2cap_chan callbacks each callback is called with
the channel lock held. Therefore, calling l2cap_conn_update_id_addr()
would cause a deadlock calling l2cap_chan_lock() on the SMP channel.
This patch moves calling smp_distribute_keys() through a workqueue so
that it is never called from an L2CAP channel callback.

Signed-off-by: Johan Hedberg <johan.hedberg@intel.com>
Signed-off-by: Marcel Holtmann <marcel@holtmann.org>
This commit is contained in:
Johan Hedberg 2014-08-11 22:06:43 +03:00 committed by Marcel Holtmann
parent 109ec2309e
commit 86d1407cb9

View File

@ -46,6 +46,7 @@ enum {
struct smp_chan {
struct l2cap_conn *conn;
struct delayed_work security_timer;
struct work_struct distribute_work;
u8 preq[7]; /* SMP Pairing Request */
u8 prsp[7]; /* SMP Pairing Response */
@ -656,11 +657,12 @@ static void smp_notify_keys(struct l2cap_conn *conn)
}
}
static int smp_distribute_keys(struct l2cap_conn *conn)
static void smp_distribute_keys(struct work_struct *work)
{
struct smp_chan *smp = container_of(work, struct smp_chan,
distribute_work);
struct smp_cmd_pairing *req, *rsp;
struct l2cap_chan *chan = conn->smp;
struct smp_chan *smp = chan->data;
struct l2cap_conn *conn = smp->conn;
struct hci_conn *hcon = conn->hcon;
struct hci_dev *hdev = hcon->hdev;
__u8 *keydist;
@ -668,13 +670,13 @@ static int smp_distribute_keys(struct l2cap_conn *conn)
BT_DBG("conn %p", conn);
if (!test_bit(HCI_CONN_LE_SMP_PEND, &hcon->flags))
return 0;
return;
rsp = (void *) &smp->prsp[1];
/* The responder sends its keys first */
if (hcon->out && (smp->remote_key_dist & 0x07))
return 0;
return;
req = (void *) &smp->preq[1];
@ -760,15 +762,13 @@ static int smp_distribute_keys(struct l2cap_conn *conn)
/* If there are still keys to be received wait for them */
if ((smp->remote_key_dist & 0x07))
return 0;
return;
clear_bit(HCI_CONN_LE_SMP_PEND, &hcon->flags);
set_bit(SMP_FLAG_COMPLETE, &smp->flags);
smp_notify_keys(conn);
smp_chan_destroy(conn);
return 0;
}
static void smp_timeout(struct work_struct *work)
@ -804,6 +804,7 @@ static struct smp_chan *smp_chan_create(struct l2cap_conn *conn)
smp->conn = conn;
chan->data = smp;
INIT_WORK(&smp->distribute_work, smp_distribute_keys);
INIT_DELAYED_WORK(&smp->security_timer, smp_timeout);
hci_conn_hold(conn->hcon);
@ -824,6 +825,12 @@ void smp_chan_destroy(struct l2cap_conn *conn)
if (!chan->data)
return;
if (work_pending(&smp->distribute_work)) {
cancel_work_sync(&smp->distribute_work);
if (!chan->data)
return;
}
complete = test_bit(SMP_FLAG_COMPLETE, &smp->flags);
mgmt_smp_complete(conn->hcon, complete);
@ -1287,7 +1294,7 @@ static int smp_cmd_master_ident(struct l2cap_conn *conn, struct sk_buff *skb)
rp->ediv, rp->rand);
smp->ltk = ltk;
if (!(smp->remote_key_dist & SMP_DIST_ID_KEY))
smp_distribute_keys(conn);
queue_work(hdev->workqueue, &smp->distribute_work);
hci_dev_unlock(hdev);
return 0;
@ -1322,6 +1329,7 @@ static int smp_cmd_ident_addr_info(struct l2cap_conn *conn,
struct l2cap_chan *chan = conn->smp;
struct smp_chan *smp = chan->data;
struct hci_conn *hcon = conn->hcon;
struct hci_dev *hdev = hcon->hdev;
bdaddr_t rpa;
BT_DBG("");
@ -1364,7 +1372,7 @@ static int smp_cmd_ident_addr_info(struct l2cap_conn *conn,
smp->id_addr_type, smp->irk, &rpa);
distribute:
smp_distribute_keys(conn);
queue_work(hdev->workqueue, &smp->distribute_work);
hci_dev_unlock(hcon->hdev);
@ -1400,7 +1408,7 @@ static int smp_cmd_sign_info(struct l2cap_conn *conn, struct sk_buff *skb)
memcpy(csrk->val, rp->csrk, sizeof(csrk->val));
}
smp->csrk = csrk;
smp_distribute_keys(conn);
queue_work(hdev->workqueue, &smp->distribute_work);
hci_dev_unlock(hdev);
return 0;
@ -1510,7 +1518,6 @@ static int smp_sig_channel(struct l2cap_chan *chan, struct sk_buff *skb)
static void smp_teardown_cb(struct l2cap_chan *chan, int err)
{
struct l2cap_conn *conn = chan->conn;
struct smp_chan *smp = chan->data;
BT_DBG("chan %p", chan);
@ -1526,14 +1533,17 @@ static void smp_resume_cb(struct l2cap_chan *chan)
struct smp_chan *smp = chan->data;
struct l2cap_conn *conn = chan->conn;
struct hci_conn *hcon = conn->hcon;
struct hci_dev *hdev = hcon->hdev;
BT_DBG("chan %p", chan);
if (test_bit(HCI_CONN_ENCRYPT, &hcon->flags))
smp_distribute_keys(conn);
if (!smp)
return;
if (smp)
cancel_delayed_work(&smp->security_timer);
cancel_delayed_work(&smp->security_timer);
if (test_bit(HCI_CONN_ENCRYPT, &hcon->flags))
queue_work(hdev->workqueue, &smp->distribute_work);
}
static void smp_ready_cb(struct l2cap_chan *chan)