Commit f9a3c20a authored by Peter Hurley's avatar Peter Hurley Committed by Gustavo Padovan
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Bluetooth: l2cap: Fix lost wakeups waiting to accept socket 



Fix race conditions which can cause lost wakeups (or misssed signals)
while waiting to accept an l2cap socket connection.

Signed-off-by: default avatarPeter Hurley <peter@hurleysoftware.com>
Signed-off-by: default avatarGustavo F. Padovan <padovan@profusion.mobi>
parent 9be4e3fb

net/bluetooth/l2cap_sock.c

+14 −14
Original line number Diff line number Diff line
@@ -235,30 +235,26 @@ static int l2cap_sock_accept(struct socket *sock, struct socket *newsock, int fl 


	lock_sock_nested(sk, SINGLE_DEPTH_NESTING);



	if (sk->sk_state != BT_LISTEN) {

		err = -EBADFD;

		goto done;

	}



	timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK);



	BT_DBG("sk %p timeo %ld", sk, timeo);



	/* Wait for an incoming connection. (wake-one). */

	add_wait_queue_exclusive(sk_sleep(sk), &wait);

	while (!(nsk = bt_accept_dequeue(sk, newsock))) {

	while (1) {

		set_current_state(TASK_INTERRUPTIBLE);

		if (!timeo) {

			err = -EAGAIN;



		if (sk->sk_state != BT_LISTEN) {

			err = -EBADFD;

			break;

		}



		release_sock(sk);

		timeo = schedule_timeout(timeo);

		lock_sock_nested(sk, SINGLE_DEPTH_NESTING);

		nsk = bt_accept_dequeue(sk, newsock);

		if (nsk)

			break;



		if (sk->sk_state != BT_LISTEN) {

			err = -EBADFD;

		if (!timeo) {

			err = -EAGAIN;

			break;

		}
@@ -266,8 +262,12 @@ static int l2cap_sock_accept(struct socket *sock, struct socket *newsock, int fl 
			err = sock_intr_errno(timeo);

			break;

		}



		release_sock(sk);

		timeo = schedule_timeout(timeo);

		lock_sock_nested(sk, SINGLE_DEPTH_NESTING);

	}

	set_current_state(TASK_RUNNING);

	__set_current_state(TASK_RUNNING);

	remove_wait_queue(sk_sleep(sk), &wait);



	if (err)