Re: [PATCH BlueZ] device: Fix race condition between device connection and disconnection

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



Hi Luiz,

Thanks for the feedback. I have sent a v2 fixing the comment style.

On Fri, Aug 21, 2020 at 10:36 AM Luiz Augusto von Dentz
<luiz.dentz@xxxxxxxxx> wrote:
>
> Hi Sonny,
>
> On Fri, Aug 21, 2020 at 12:47 AM Sonny Sasaka <sonnysasaka@xxxxxxxxxxxx> wrote:
> >
> > When Connect() is called and waiting for return, dev_disconnected may be
> > called due to MGMT_EV_DEVICE_DISCONNECTED event from kernel. In that
> > case reply to client that the connection failed otherwise the dbus
> > method will timeout because bluetoothd never replies.
> >
> > Tested with simulation of a lot of Connect() to bluetooth devices and
> > check that error is returned from bluetoothd rather than dbus timeout
> > when this race condition happens.
> >
> > Reviewed-by: Miao-chen Chou <mcchou@xxxxxxxxxxxx>
> >
> > ---
> >  src/device.c | 12 ++++++++++++
> >  1 file changed, 12 insertions(+)
> >
> > diff --git a/src/device.c b/src/device.c
> > index 7b7808405..55e7b4042 100644
> > --- a/src/device.c
> > +++ b/src/device.c
> > @@ -3006,6 +3006,7 @@ void device_add_connection(struct btd_device *dev, uint8_t bdaddr_type)
> >  void device_remove_connection(struct btd_device *device, uint8_t bdaddr_type)
> >  {
> >         struct bearer_state *state = get_state(device, bdaddr_type);
> > +       DBusMessage *reply;
> >
> >         if (!state->connected)
> >                 return;
> > @@ -3020,6 +3021,17 @@ void device_remove_connection(struct btd_device *device, uint8_t bdaddr_type)
> >                 device->disconn_timer = 0;
> >         }
> >
> > +       // This could be executed while the client is waiting for Connect() but
> > +       // att_connect_cb has not been invoked.
> > +       // In that case reply the client that the connection failed.
>
> Please use C style comment /* */
>
> > +       if (device->connect) {
> > +               DBG("connection removed while Connect() is waiting reply");
> > +               reply = btd_error_failed(device->connect, "Disconnected early");
> > +               g_dbus_send_message(dbus_conn, reply);
> > +               dbus_message_unref(device->connect);
> > +               device->connect = NULL;
> > +       }
> > +
> >         while (device->disconnects) {
> >                 DBusMessage *msg = device->disconnects->data;
> >
> > --
> > 2.26.2
> >
>
> Otherwise it looks good.
>
> --
> Luiz Augusto von Dentz



[Index of Archives]     [Bluez Devel]     [Linux Wireless Networking]     [Linux Wireless Personal Area Networking]     [Linux ATH6KL]     [Linux USB Devel]     [Linux Media Drivers]     [Linux Audio Users]     [Linux Kernel]     [Linux SCSI]     [Big List of Linux Books]

  Powered by Linux