[PATCH 4/7] Bluetooth: l2cap: Fix lost wakeups waiting to accept socket
From: Peter Hurley <hidden>
Date: 2011-07-24 04:10:52
Subsystem:
bluetooth subsystem, the rest · Maintainers:
Marcel Holtmann, Luiz Augusto von Dentz, Linus Torvalds
Fix race conditions which can cause lost wakeups (or misssed signals) while waiting to accept an l2cap socket connection. Signed-off-by: Peter Hurley <redacted> --- net/bluetooth/l2cap_sock.c | 28 ++++++++++++++-------------- 1 files changed, 14 insertions(+), 14 deletions(-)
diff --git a/net/bluetooth/l2cap_sock.c b/net/bluetooth/l2cap_sock.c
index 8248303..e13a5cc 100644
--- a/net/bluetooth/l2cap_sock.c
+++ b/net/bluetooth/l2cap_sock.c@@ -274,30 +274,26 @@ 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; }
@@ -305,8 +301,12 @@ 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)
--
1.7.4.1