Bluetooth: invert locking order in connect path

This move some checking code that was in l2cap_sock_connect() to
l2cap_chan_connect(). Thus we can invert the lock calls, i.e., call
lock_sock() before hci_dev_lock() to avoid a deadlock scenario.

Acked-by: Marcel Holtmann <marcel@holtmann.org>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>

1 files changed, 3 insertions, 58 deletions

diff --git a/net/bluetooth/l2cap_sock.c b/net/bluetooth/l2cap_sock.c
index fbdc8b38d9e..6c7d4323e79 100644
--- a/net/bluetooth/l2cap_sock.c
+++ b/net/bluetooth/l2cap_sock.c
@@ -121,70 +121,15 @@ static int l2cap_sock_connect(struct socket *sock, struct sockaddr *addr, int al
 	if (la.l2_cid && la.l2_psm)
 		return -EINVAL;
 
-	lock_sock(sk);
-
-	if (chan->chan_type == L2CAP_CHAN_CONN_ORIENTED
-			&& !(la.l2_psm || la.l2_cid)) {
-		err = -EINVAL;
-		goto done;
-	}
-
-	switch (chan->mode) {
-	case L2CAP_MODE_BASIC:
-		break;
-	case L2CAP_MODE_ERTM:
-	case L2CAP_MODE_STREAMING:
-		if (!disable_ertm)
-			break;
-		/* fall through */
-	default:
-		err = -ENOTSUPP;
-		goto done;
-	}
-
-	switch (sk->sk_state) {
-	case BT_CONNECT:
-	case BT_CONNECT2:
-	case BT_CONFIG:
-		/* Already connecting */
-		goto wait;
-
-	case BT_CONNECTED:
-		/* Already connected */
-		err = -EISCONN;
-		goto done;
-
-	case BT_OPEN:
-	case BT_BOUND:
-		/* Can connect */
-		break;
-
-	default:
-		err = -EBADFD;
-		goto done;
-	}
-
-	/* PSM must be odd and lsb of upper byte must be 0 */
-	if ((__le16_to_cpu(la.l2_psm) & 0x0101) != 0x0001 && !la.l2_cid &&
-					chan->chan_type != L2CAP_CHAN_RAW) {
-		err = -EINVAL;
-		goto done;
-	}
-
-	/* Set destination address and psm */
-	bacpy(&bt_sk(sk)->dst, &la.l2_bdaddr);
-	chan->psm = la.l2_psm;
-	chan->dcid = la.l2_cid;
-
-	err = l2cap_chan_connect(chan);
+	err = l2cap_chan_connect(chan, la.l2_psm, la.l2_cid, &la.l2_bdaddr);
 	if (err)
 		goto done;
 
-wait:
 	err = bt_sock_wait_state(sk, BT_CONNECTED,
 			sock_sndtimeo(sk, flags & O_NONBLOCK));
 done:
-	release_sock(sk);
+	if (sock_owned_by_user(sk))
+		release_sock(sk);
 	return err;
 }