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Diffstat (limited to 'net/bluetooth/l2cap_core.c')
-rw-r--r--net/bluetooth/l2cap_core.c86
1 files changed, 73 insertions, 13 deletions
diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c
index 1f34b82ca0ec..9c24947aa41e 100644
--- a/net/bluetooth/l2cap_core.c
+++ b/net/bluetooth/l2cap_core.c
@@ -1990,7 +1990,7 @@ 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;
@@ -3764,7 +3764,8 @@ 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);
@@ -5813,6 +5814,19 @@ 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_LE_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);
@@ -6001,6 +6015,18 @@ static inline int l2cap_ecred_conn_req(struct l2cap_conn *conn,
psm = req->psm;
+ /* 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_LE_BAD_PSM;
+ goto response;
+ }
+
BT_DBG("psm 0x%2.2x mtu %u mps %u", __le16_to_cpu(psm), mtu, mps);
memset(&pdu, 0, sizeof(pdu));
@@ -6885,6 +6911,7 @@ 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;
@@ -6909,15 +6936,32 @@ 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);
}
}
@@ -7297,11 +7341,27 @@ 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 %u->%u", chan->buffer_seq,
@@ -7324,8 +7384,8 @@ 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;
}
@@ -7581,6 +7641,7 @@ 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);
@@ -8426,9 +8487,8 @@ void l2cap_recv_acldata(struct hci_conn *hcon, struct sk_buff *skb, u16 flags)
* expected length.
*/
if (skb->len < L2CAP_LEN_SIZE) {
- if (l2cap_recv_frag(conn, skb, conn->mtu) < 0)
- goto drop;
- return;
+ l2cap_recv_frag(conn, skb, conn->mtu);
+ break;
}
len = get_unaligned_le16(skb->data) + L2CAP_HDR_SIZE;
@@ -8472,7 +8532,7 @@ void l2cap_recv_acldata(struct hci_conn *hcon, struct sk_buff *skb, u16 flags)
/* Header still could not be read just continue */
if (conn->rx_skb->len < L2CAP_LEN_SIZE)
- return;
+ break;
}
if (skb->len > conn->rx_len) {