Re: [syzbot] Re: [PATCH v3] Bluetooth: SCO: Use disable_delayed_work_sync

From: syzbot
Date: Wed Oct 02 2024 - 15:47:13 EST


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Subject: Re: [PATCH v3] Bluetooth: SCO: Use disable_delayed_work_sync
Author: luiz.dentz@xxxxxxxxx

#syz test

On Wed, Oct 2, 2024 at 3:19 PM Luiz Augusto von Dentz
<luiz.dentz@xxxxxxxxx> wrote:
>
> #syz test
>
> On Wed, Oct 2, 2024 at 3:04 PM Luiz Augusto von Dentz
> <luiz.dentz@xxxxxxxxx> wrote:
> >
> > From: Luiz Augusto von Dentz <luiz.von.dentz@xxxxxxxxx>
> >
> > This makes use of disable_delayed_work_sync instead
> > cancel_delayed_work_sync as it not only cancel the ongoing work but also
> > disables new submit which is disarable since the object holding the work
> > is about to be freed.
> >
> > In addition to it remove call to sco_sock_set_timer on __sco_sock_close
> > since at that point it is useless to set a timer as the sk will be freed
> > there is nothing to be done in sco_sock_timeout.
> >
> > Reported-by: syzbot+4c0d0c4cde787116d465@xxxxxxxxxxxxxxxxxxxxxxxxx
> > Closes: https://syzkaller.appspot.com/bug?extid=4c0d0c4cde787116d465
> > Fixes: ba316be1b6a0 ("Bluetooth: schedule SCO timeouts with delayed_work")
> > Signed-off-by: Luiz Augusto von Dentz <luiz.von.dentz@xxxxxxxxx>
> > ---
> > net/bluetooth/sco.c | 13 +------------
> > 1 file changed, 1 insertion(+), 12 deletions(-)
> >
> > diff --git a/net/bluetooth/sco.c b/net/bluetooth/sco.c
> > index a5ac160c592e..2b1e66976068 100644
> > --- a/net/bluetooth/sco.c
> > +++ b/net/bluetooth/sco.c
> > @@ -208,7 +208,7 @@ static void sco_conn_del(struct hci_conn *hcon, int err)
> > }
> >
> > /* Ensure no more work items will run before freeing conn. */
> > - cancel_delayed_work_sync(&conn->timeout_work);
> > + disable_delayed_work_sync(&conn->timeout_work);
> >
> > hcon->sco_data = NULL;
> > kfree(conn);
> > @@ -442,17 +442,6 @@ static void __sco_sock_close(struct sock *sk)
> >
> > case BT_CONNECTED:
> > case BT_CONFIG:
> > - if (sco_pi(sk)->conn->hcon) {
> > - sk->sk_state = BT_DISCONN;
> > - sco_sock_set_timer(sk, SCO_DISCONN_TIMEOUT);
> > - sco_conn_lock(sco_pi(sk)->conn);
> > - hci_conn_drop(sco_pi(sk)->conn->hcon);
> > - sco_pi(sk)->conn->hcon = NULL;
> > - sco_conn_unlock(sco_pi(sk)->conn);
> > - } else
> > - sco_chan_del(sk, ECONNRESET);
> > - break;
> > -
> > case BT_CONNECT2:
> > case BT_CONNECT:
> > case BT_DISCONN:
> > --
> > 2.46.1
> >
>
>
> --
> Luiz Augusto von Dentz



--
Luiz Augusto von Dentz