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: Peter Hurley <peter@hurleysoftware.com>
Signed-off-by: Gustavo F. Padovan <padovan@profusion.mobi>

1 files changed, 14 insertions, 14 deletions

diff --git a/net/bluetooth/l2cap_sock.c b/net/bluetooth/l2cap_sock.c
index 5c36b3e8739c..7d713b1c4cbd 100644
--- a/net/bluetooth/l2cap_sock.c
+++ b/net/bluetooth/l2cap_sock.c
@@ -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)