summaryrefslogtreecommitdiffstats
path: root/net/bluetooth/l2cap_core.c
diff options
context:
space:
mode:
Diffstat (limited to 'net/bluetooth/l2cap_core.c')
-rw-r--r--net/bluetooth/l2cap_core.c84
1 files changed, 71 insertions, 13 deletions
diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c
index 65d20bdff..fd6cd47a6 100644
--- a/net/bluetooth/l2cap_core.c
+++ b/net/bluetooth/l2cap_core.c
@@ -63,6 +63,9 @@ static void l2cap_send_disconn_req(struct l2cap_chan *chan, int err);
static void l2cap_tx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
struct sk_buff_head *skbs, u8 event);
+static void l2cap_retrans_timeout(struct work_struct *work);
+static void l2cap_monitor_timeout(struct work_struct *work);
+static void l2cap_ack_timeout(struct work_struct *work);
static inline u8 bdaddr_type(u8 link_type, u8 bdaddr_type)
{
@@ -470,6 +473,9 @@ struct l2cap_chan *l2cap_chan_create(void)
write_unlock(&chan_list_lock);
INIT_DELAYED_WORK(&chan->chan_timer, l2cap_chan_timeout);
+ INIT_DELAYED_WORK(&chan->retrans_timer, l2cap_retrans_timeout);
+ INIT_DELAYED_WORK(&chan->monitor_timer, l2cap_monitor_timeout);
+ INIT_DELAYED_WORK(&chan->ack_timer, l2cap_ack_timeout);
chan->state = BT_OPEN;
@@ -1818,7 +1824,7 @@ static struct l2cap_chan *l2cap_global_chan_by_psm(int state, __le16 psm,
if (link_type == LE_LINK && c->src_type == BDADDR_BREDR)
continue;
- if (c->psm == psm) {
+ if (c->chan_type != L2CAP_CHAN_FIXED && c->psm == psm) {
int src_match, dst_match;
int src_any, dst_any;
@@ -3154,10 +3160,6 @@ int l2cap_ertm_init(struct l2cap_chan *chan)
chan->rx_state = L2CAP_RX_STATE_RECV;
chan->tx_state = L2CAP_TX_STATE_XMIT;
- INIT_DELAYED_WORK(&chan->retrans_timer, l2cap_retrans_timeout);
- INIT_DELAYED_WORK(&chan->monitor_timer, l2cap_monitor_timeout);
- INIT_DELAYED_WORK(&chan->ack_timer, l2cap_ack_timeout);
-
skb_queue_head_init(&chan->srej_q);
err = l2cap_seq_list_init(&chan->srej_list, chan->tx_win);
@@ -3549,7 +3551,8 @@ done:
l2cap_add_conf_opt(&ptr, L2CAP_CONF_RFC,
sizeof(rfc), (unsigned long) &rfc, endptr - ptr);
- if (test_bit(FLAG_EFS_ENABLE, &chan->flags)) {
+ if (remote_efs &&
+ test_bit(FLAG_EFS_ENABLE, &chan->flags)) {
chan->remote_id = efs.id;
chan->remote_stype = efs.stype;
chan->remote_msdu = le16_to_cpu(efs.msdu);
@@ -4047,6 +4050,12 @@ static int l2cap_connect_create_rsp(struct l2cap_conn *conn,
}
}
+ chan = l2cap_chan_hold_unless_zero(chan);
+ if (!chan) {
+ err = -EBADSLT;
+ goto unlock;
+ }
+
err = 0;
l2cap_chan_lock(chan);
@@ -4076,6 +4085,7 @@ static int l2cap_connect_create_rsp(struct l2cap_conn *conn,
}
l2cap_chan_unlock(chan);
+ l2cap_chan_put(chan);
unlock:
mutex_unlock(&conn->chan_lock);
@@ -5543,6 +5553,19 @@ static int l2cap_le_connect_req(struct l2cap_conn *conn,
BT_DBG("psm 0x%2.2x scid 0x%4.4x mtu %u mps %u", __le16_to_cpu(psm),
scid, mtu, mps);
+ /* BLUETOOTH CORE SPECIFICATION Version 5.3 | Vol 3, Part A
+ * page 1059:
+ *
+ * Valid range: 0x0001-0x00ff
+ *
+ * Table 4.15: L2CAP_LE_CREDIT_BASED_CONNECTION_REQ SPSM ranges
+ */
+ if (!psm || __le16_to_cpu(psm) > L2CAP_PSM_LE_DYN_END) {
+ result = L2CAP_CR_BAD_PSM;
+ chan = NULL;
+ goto response;
+ }
+
/* Check if we have socket listening on psm */
pchan = l2cap_global_chan_by_psm(BT_LISTEN, psm, &conn->hcon->src,
&conn->hcon->dst, LE_LINK);
@@ -6246,6 +6269,7 @@ static int l2cap_rx_state_recv(struct l2cap_chan *chan,
struct l2cap_ctrl *control,
struct sk_buff *skb, u8 event)
{
+ struct l2cap_ctrl local_control;
int err = 0;
bool skb_in_use = false;
@@ -6270,15 +6294,32 @@ static int l2cap_rx_state_recv(struct l2cap_chan *chan,
chan->buffer_seq = chan->expected_tx_seq;
skb_in_use = true;
+ /* l2cap_reassemble_sdu may free skb, hence invalidate
+ * control, so make a copy in advance to use it after
+ * l2cap_reassemble_sdu returns and to avoid the race
+ * condition, for example:
+ *
+ * The current thread calls:
+ * l2cap_reassemble_sdu
+ * chan->ops->recv == l2cap_sock_recv_cb
+ * __sock_queue_rcv_skb
+ * Another thread calls:
+ * bt_sock_recvmsg
+ * skb_recv_datagram
+ * skb_free_datagram
+ * Then the current thread tries to access control, but
+ * it was freed by skb_free_datagram.
+ */
+ local_control = *control;
err = l2cap_reassemble_sdu(chan, skb, control);
if (err)
break;
- if (control->final) {
+ if (local_control.final) {
if (!test_and_clear_bit(CONN_REJ_ACT,
&chan->conn_state)) {
- control->final = 0;
- l2cap_retransmit_all(chan, control);
+ local_control.final = 0;
+ l2cap_retransmit_all(chan, &local_control);
l2cap_ertm_send(chan);
}
}
@@ -6658,11 +6699,27 @@ static int l2cap_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
static int l2cap_stream_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
struct sk_buff *skb)
{
+ /* l2cap_reassemble_sdu may free skb, hence invalidate control, so store
+ * the txseq field in advance to use it after l2cap_reassemble_sdu
+ * returns and to avoid the race condition, for example:
+ *
+ * The current thread calls:
+ * l2cap_reassemble_sdu
+ * chan->ops->recv == l2cap_sock_recv_cb
+ * __sock_queue_rcv_skb
+ * Another thread calls:
+ * bt_sock_recvmsg
+ * skb_recv_datagram
+ * skb_free_datagram
+ * Then the current thread tries to access control, but it was freed by
+ * skb_free_datagram.
+ */
+ u16 txseq = control->txseq;
+
BT_DBG("chan %p, control %p, skb %p, state %d", chan, control, skb,
chan->rx_state);
- if (l2cap_classify_txseq(chan, control->txseq) ==
- L2CAP_TXSEQ_EXPECTED) {
+ if (l2cap_classify_txseq(chan, txseq) == L2CAP_TXSEQ_EXPECTED) {
l2cap_pass_to_tx(chan, control);
BT_DBG("buffer_seq %d->%d", chan->buffer_seq,
@@ -6685,8 +6742,8 @@ static int l2cap_stream_rx(struct l2cap_chan *chan, struct l2cap_ctrl *control,
}
}
- chan->last_acked_seq = control->txseq;
- chan->expected_tx_seq = __next_seq(chan, control->txseq);
+ chan->last_acked_seq = txseq;
+ chan->expected_tx_seq = __next_seq(chan, txseq);
return 0;
}
@@ -6924,6 +6981,7 @@ static void l2cap_data_channel(struct l2cap_conn *conn, u16 cid,
return;
}
+ l2cap_chan_hold(chan);
l2cap_chan_lock(chan);
} else {
BT_DBG("unknown cid 0x%4.4x", cid);
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-21 12:19:09 +0000