Re: [PATCH] bluetooth: bfusb: Check the endpoint type at probe

[Zheyu Ma]

On Fri, May 13, 2022 at 8:53 PM Marcel Holtmann <marcel@xxxxxxxxxxxx> wrote:
>
> Hi Zheyu,
>
> > The driver reported an warning in usb_submit_urb() which is caused by
> > wrong endpoint type.
> >
> > [    3.295630] usb 1-1: BOGUS urb xfer, pipe 3 != type 1
> > [    3.295916] WARNING: CPU: 0 PID: 33 at drivers/usb/core/urb.c:503 usb_submit_urb+0xcd9/0x18b0
> > [    3.298155] RIP: 0010:usb_submit_urb+0xcd9/0x18b0
> > [    3.302451] Call Trace:
> > [    3.302580]  <TASK>
> > [    3.302698]  bfusb_rx_submit+0x24e/0x390 [bfusb]
> > [    3.302938]  bfusb_open+0x50/0x90 [bfusb]
> >
> > Fix this by checking the endpoint type at first.
> >
> > Signed-off-by: Zheyu Ma <zheyuma97@xxxxxxxxx>
> > ---
> > drivers/bluetooth/bfusb.c | 4 +++-
> > 1 file changed, 3 insertions(+), 1 deletion(-)
> >
> > diff --git a/drivers/bluetooth/bfusb.c b/drivers/bluetooth/bfusb.c
> > index cab93935cc7f..447b6876c552 100644
> > --- a/drivers/bluetooth/bfusb.c
> > +++ b/drivers/bluetooth/bfusb.c
> > @@ -613,7 +613,9 @@ static int bfusb_probe(struct usb_interface *intf, const struct usb_device_id *i
> >       bulk_out_ep = &intf->cur_altsetting->endpoint[0];
> >       bulk_in_ep  = &intf->cur_altsetting->endpoint[1];
> >
> > -     if (!bulk_out_ep || !bulk_in_ep) {
> > +     if (!bulk_out_ep || !bulk_in_ep ||
> > +             !usb_endpoint_is_bulk_out(&bulk_out_ep->desc) ||
> > +             !usb_endpoint_is_bulk_in(&bulk_in_ep->desc)) {
> >               BT_ERR("Bulk endpoints not found");
> >               goto done;
> >       }
>
> how are you getting this. This driver only works on one specific piece of hardware.

Actually, I used a virtual device to test the driver, and got the above warning.
The USB device may be programmable and malicious, so the driver should
carefully treat the input that the device provided.

Regards,
Zheyu Ma