| From 25717382c1dd0ddced2059053e3ca5088665f7a5 Mon Sep 17 00:00:00 2001 |
| From: Jeffy Chen <jeffy.chen@rock-chips.com> |
| Date: Tue, 27 Jun 2017 17:34:42 +0800 |
| Subject: Bluetooth: bnep: fix possible might sleep error in bnep_session |
| |
| From: Jeffy Chen <jeffy.chen@rock-chips.com> |
| |
| commit 25717382c1dd0ddced2059053e3ca5088665f7a5 upstream. |
| |
| It looks like bnep_session has same pattern as the issue reported in |
| old rfcomm: |
| |
| while (1) { |
| set_current_state(TASK_INTERRUPTIBLE); |
| if (condition) |
| break; |
| // may call might_sleep here |
| schedule(); |
| } |
| __set_current_state(TASK_RUNNING); |
| |
| Which fixed at: |
| dfb2fae Bluetooth: Fix nested sleeps |
| |
| So let's fix it at the same way, also follow the suggestion of: |
| https://lwn.net/Articles/628628/ |
| |
| Signed-off-by: Jeffy Chen <jeffy.chen@rock-chips.com> |
| Reviewed-by: Brian Norris <briannorris@chromium.org> |
| Reviewed-by: AL Yu-Chen Cho <acho@suse.com> |
| Signed-off-by: Marcel Holtmann <marcel@holtmann.org> |
| Cc: Jiri Slaby <jslaby@suse.cz> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| |
| --- |
| net/bluetooth/bnep/core.c | 11 +++++------ |
| 1 file changed, 5 insertions(+), 6 deletions(-) |
| |
| --- a/net/bluetooth/bnep/core.c |
| +++ b/net/bluetooth/bnep/core.c |
| @@ -451,16 +451,16 @@ static int bnep_session(void *arg) |
| struct net_device *dev = s->dev; |
| struct sock *sk = s->sock->sk; |
| struct sk_buff *skb; |
| - wait_queue_t wait; |
| + DEFINE_WAIT_FUNC(wait, woken_wake_function); |
| |
| BT_DBG(""); |
| |
| set_user_nice(current, -15); |
| |
| - init_waitqueue_entry(&wait, current); |
| add_wait_queue(sk_sleep(sk), &wait); |
| while (1) { |
| - set_current_state(TASK_INTERRUPTIBLE); |
| + /* Ensure session->terminate is updated */ |
| + smp_mb__before_atomic(); |
| |
| if (atomic_read(&s->terminate)) |
| break; |
| @@ -482,9 +482,8 @@ static int bnep_session(void *arg) |
| break; |
| netif_wake_queue(dev); |
| |
| - schedule(); |
| + wait_woken(&wait, TASK_INTERRUPTIBLE, MAX_SCHEDULE_TIMEOUT); |
| } |
| - __set_current_state(TASK_RUNNING); |
| remove_wait_queue(sk_sleep(sk), &wait); |
| |
| /* Cleanup session */ |
| @@ -621,7 +620,7 @@ int bnep_del_connection(struct bnep_conn |
| s = __bnep_get_session(req->dst); |
| if (s) { |
| atomic_inc(&s->terminate); |
| - wake_up_process(s->task); |
| + wake_up_interruptible(sk_sleep(s->sock->sk)); |
| } else |
| err = -ENOENT; |
| |