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[1/2] Bluetooth: L2CAP: Use DEFER_SETUP to group ECRED connections

Message ID 20200312222454.5079-2-luiz.dentz@gmail.com
State New
Headers show
Series [1/2] Bluetooth: L2CAP: Use DEFER_SETUP to group ECRED connections | expand

Commit Message

Luiz Augusto von Dentz March 12, 2020, 10:24 p.m. UTC
From: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>

This uses the DEFER_SETUP flag to group channels with
L2CAP_CREDIT_BASED_CONNECTION_REQ.

Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@intel.com>
---
 include/net/bluetooth/l2cap.h |   5 ++
 net/bluetooth/l2cap_core.c    | 130 +++++++++++++++++++++++++++++++---
 net/bluetooth/l2cap_sock.c    |  13 ++--
 3 files changed, 133 insertions(+), 15 deletions(-)
diff mbox series

Patch

diff --git a/include/net/bluetooth/l2cap.h b/include/net/bluetooth/l2cap.h
index 537aaead259f..dada14d0622c 100644
--- a/include/net/bluetooth/l2cap.h
+++ b/include/net/bluetooth/l2cap.h
@@ -47,6 +47,7 @@ 
 #define L2CAP_DEFAULT_ACC_LAT		0xFFFFFFFF
 #define L2CAP_BREDR_MAX_PAYLOAD		1019    /* 3-DH5 packet */
 #define L2CAP_LE_MIN_MTU		23
+#define L2CAP_ECRED_CONN_SCID_MAX	5
 
 #define L2CAP_DISC_TIMEOUT		msecs_to_jiffies(100)
 #define L2CAP_DISC_REJ_TIMEOUT		msecs_to_jiffies(5000)
@@ -660,6 +661,7 @@  struct l2cap_ops {
 	void			(*suspend) (struct l2cap_chan *chan);
 	void			(*set_shutdown) (struct l2cap_chan *chan);
 	long			(*get_sndtimeo) (struct l2cap_chan *chan);
+	struct pid		*(*get_peer_pid) (struct l2cap_chan *chan);
 	struct sk_buff		*(*alloc_skb) (struct l2cap_chan *chan,
 					       unsigned long hdr_len,
 					       unsigned long len, int nb);
@@ -983,6 +985,9 @@  void l2cap_chan_set_defaults(struct l2cap_chan *chan);
 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);
+typedef void (*l2cap_chan_func_t)(struct l2cap_chan *chan, void *data);
+void l2cap_chan_list(struct l2cap_conn *conn, l2cap_chan_func_t func,
+		     void *data);
 void l2cap_chan_del(struct l2cap_chan *chan, int err);
 void l2cap_send_conn_req(struct l2cap_chan *chan);
 void l2cap_move_start(struct l2cap_chan *chan);
diff --git a/net/bluetooth/l2cap_core.c b/net/bluetooth/l2cap_core.c
index 5e6e35ab44dd..20c1d5f9c238 100644
--- a/net/bluetooth/l2cap_core.c
+++ b/net/bluetooth/l2cap_core.c
@@ -678,6 +678,29 @@  void l2cap_chan_del(struct l2cap_chan *chan, int err)
 }
 EXPORT_SYMBOL_GPL(l2cap_chan_del);
 
+static void __l2cap_chan_list(struct l2cap_conn *conn, l2cap_chan_func_t func,
+			      void *data)
+{
+	struct l2cap_chan *chan;
+
+	list_for_each_entry(chan, &conn->chan_l, list) {
+		func(chan, data);
+	}
+}
+
+void l2cap_chan_list(struct l2cap_conn *conn, l2cap_chan_func_t func,
+		     void *data)
+{
+	if (!conn)
+		return;
+
+	mutex_lock(&conn->chan_lock);
+	__l2cap_chan_list(conn, func, data);
+	mutex_unlock(&conn->chan_lock);
+}
+
+EXPORT_SYMBOL_GPL(l2cap_chan_list);
+
 static void l2cap_conn_update_id_addr(struct work_struct *work)
 {
 	struct l2cap_conn *conn = container_of(work, struct l2cap_conn,
@@ -1356,29 +1379,77 @@  static void l2cap_le_connect(struct l2cap_chan *chan)
 		       sizeof(req), &req);
 }
 
-static void l2cap_ecred_connect(struct l2cap_chan *chan)
-{
-	struct l2cap_conn *conn = chan->conn;
+struct l2cap_ecred_conn_data {
 	struct {
 		struct l2cap_ecred_conn_req req;
-		__le16 scid;
+		__le16 scid[5];
 	} __packed pdu;
+	struct l2cap_chan *chan;
+	struct pid *pid;
+	int count;
+};
+
+static void l2cap_ecred_defer_connect(struct l2cap_chan *chan, void *data)
+{
+	struct l2cap_ecred_conn_data *conn = data;
+	struct pid *pid;
+
+	if (chan == conn->chan)
+		return;
+
+	if (!test_and_clear_bit(FLAG_DEFER_SETUP, &chan->flags))
+		return;
+
+	pid = chan->ops->get_peer_pid(chan);
+
+	/* Only add deferred channels with the same PID/PSM */
+	if (conn->pid != pid || chan->psm != conn->chan->psm || chan->ident ||
+	    chan->mode != L2CAP_MODE_EXT_FLOWCTL || chan->state != BT_CONNECT)
+		return;
+
+	if (test_and_set_bit(FLAG_ECRED_CONN_REQ_SENT, &chan->flags))
+		return;
+
+	/* Set the same ident so we can match on the rsp */
+	chan->ident = conn->chan->ident;
+
+	/* Include all channels deferred */
+	conn->pdu.scid[conn->count] = cpu_to_le16(chan->scid);
+
+	conn->count++;
+}
+
+static void l2cap_ecred_connect(struct l2cap_chan *chan)
+{
+	struct l2cap_conn *conn = chan->conn;
+	struct l2cap_ecred_conn_data data;
+
+	if (test_bit(FLAG_DEFER_SETUP, &chan->flags))
+		return;
 
 	if (test_and_set_bit(FLAG_ECRED_CONN_REQ_SENT, &chan->flags))
 		return;
 
 	l2cap_ecred_init(chan, 0);
 
-	pdu.req.psm     = chan->psm;
-	pdu.req.mtu     = cpu_to_le16(chan->imtu);
-	pdu.req.mps     = cpu_to_le16(chan->mps);
-	pdu.req.credits = cpu_to_le16(chan->rx_credits);
-	pdu.scid        = cpu_to_le16(chan->scid);
+	data.pdu.req.psm     = chan->psm;
+	data.pdu.req.mtu     = cpu_to_le16(chan->imtu);
+	data.pdu.req.mps     = cpu_to_le16(chan->mps);
+	data.pdu.req.credits = cpu_to_le16(chan->rx_credits);
+	data.pdu.scid[0]     = cpu_to_le16(chan->scid);
 
 	chan->ident = l2cap_get_ident(conn);
+	data.pid = chan->ops->get_peer_pid(chan);
+
+	data.count = 1;
+	data.chan = chan;
+	data.pid = chan->ops->get_peer_pid(chan);
+
+	__l2cap_chan_list(conn, l2cap_ecred_defer_connect, &data);
 
 	l2cap_send_cmd(conn, chan->ident, L2CAP_ECRED_CONN_REQ,
-		       sizeof(pdu), &pdu);
+		       sizeof(data.pdu.req) + data.count * sizeof(__le16),
+		       &data.pdu);
 }
 
 static void l2cap_le_start(struct l2cap_chan *chan)
@@ -7694,6 +7765,29 @@  static bool is_valid_psm(u16 psm, u8 dst_type) {
 	return ((psm & 0x0101) == 0x0001);
 }
 
+struct l2cap_chan_data {
+	struct l2cap_chan *chan;
+	struct pid *pid;
+	int count;
+};
+
+static void l2cap_chan_by_pid(struct l2cap_chan *chan, void *data)
+{
+	struct l2cap_chan_data *d = data;
+
+	if (chan == d->chan)
+		return;
+
+	/* Only count deferred channels with the same PID/PSM */
+	if (d->pid != chan->ops->get_peer_pid(chan) ||
+	    !test_bit(FLAG_DEFER_SETUP, &chan->flags) ||
+	    chan->psm != d->chan->psm || chan->ident ||
+	    chan->state != BT_CONNECT)
+		return;
+
+	d->count++;
+}
+
 int l2cap_chan_connect(struct l2cap_chan *chan, __le16 psm, u16 cid,
 		       bdaddr_t *dst, u8 dst_type)
 {
@@ -7813,6 +7907,22 @@  int l2cap_chan_connect(struct l2cap_chan *chan, __le16 psm, u16 cid,
 		goto done;
 	}
 
+	if (chan->mode == L2CAP_MODE_EXT_FLOWCTL) {
+		struct l2cap_chan_data data;
+
+		data.chan = chan;
+		data.pid = chan->ops->get_peer_pid(chan);
+		data.count = 0;
+
+		l2cap_chan_list(conn, l2cap_chan_by_pid, &data);
+		/* Check if there isn't too many channels being connected */
+		if (!(data.count < L2CAP_ECRED_CONN_SCID_MAX - 1)) {
+			hci_conn_drop(hcon);
+			err = -EPROTO;
+			goto done;
+		}
+	}
+
 	mutex_lock(&conn->chan_lock);
 	l2cap_chan_lock(chan);
 
diff --git a/net/bluetooth/l2cap_sock.c b/net/bluetooth/l2cap_sock.c
index 40fb10b591bd..e43a90e05972 100644
--- a/net/bluetooth/l2cap_sock.c
+++ b/net/bluetooth/l2cap_sock.c
@@ -549,11 +549,6 @@  static int l2cap_sock_getsockopt(struct socket *sock, int level, int optname,
 		break;
 
 	case BT_DEFER_SETUP:
-		if (sk->sk_state != BT_BOUND && sk->sk_state != BT_LISTEN) {
-			err = -EINVAL;
-			break;
-		}
-
 		if (put_user(test_bit(BT_SK_DEFER_SETUP, &bt_sk(sk)->flags),
 			     (u32 __user *) optval))
 			err = -EFAULT;
@@ -1504,6 +1499,13 @@  static long l2cap_sock_get_sndtimeo_cb(struct l2cap_chan *chan)
 	return sk->sk_sndtimeo;
 }
 
+static struct pid *l2cap_sock_get_peer_pid_cb(struct l2cap_chan *chan)
+{
+	struct sock *sk = chan->data;
+
+	return sk->sk_peer_pid;
+}
+
 static void l2cap_sock_suspend_cb(struct l2cap_chan *chan)
 {
 	struct sock *sk = chan->data;
@@ -1525,6 +1527,7 @@  static const struct l2cap_ops l2cap_chan_ops = {
 	.suspend		= l2cap_sock_suspend_cb,
 	.set_shutdown		= l2cap_sock_set_shutdown_cb,
 	.get_sndtimeo		= l2cap_sock_get_sndtimeo_cb,
+	.get_peer_pid		= l2cap_sock_get_peer_pid_cb,
 	.alloc_skb		= l2cap_sock_alloc_skb_cb,
 };