On Fri, 23 Sep 2011, Matthias Dellweg wrote:
> Am Thu, 22 Sep 2011 23:56:56 +0200
> schrieb Matthias Dellweg <2500@xxxxxx>:
>
> > + if ((requesttype == 0xa1) && (request == 0x00)
> > + && (usb_find_alt_setting(ps->dev->actconfig, index >> 8,
> > index & 0xff)
> > + ->desc.bInterfaceClass == USB_CLASS_PRINTER))
> > + index >>= 8;
>
> I just woke up and realised this is a very bad idea if there is no such
> setting...
> So here's the next version I'd like to propose for comments:
This is basically okay. But your mailer has mangled the whitespace.
> diff --git a/drivers/usb/core/devio.c b/drivers/usb/core/devio.c
> index 37518df..d2efc97 100644
> --- a/drivers/usb/core/devio.c
> +++ b/drivers/usb/core/devio.c
> @@ -607,9 +607,10 @@ static int findintfep(struct usb_device *dev, unsigned int ep)
> }
>
> static int check_ctrlrecip(struct dev_state *ps, unsigned int requesttype,
> - unsigned int index)
> + unsigned int request, unsigned int index)
> {
> int ret = 0;
> + struct usb_host_interface *alt_setting;
>
> if (ps->dev->state != USB_STATE_UNAUTHENTICATED
> && ps->dev->state != USB_STATE_ADDRESS
> @@ -618,6 +619,15 @@ static int check_ctrlrecip(struct dev_state *ps, unsigned int requesttype,
> if (USB_TYPE_VENDOR == (USB_TYPE_MASK & requesttype))
> return 0;
>
> + /* check for the special corner case 'get_device_id' in the printer class specification,
> + * where wIndex is (configuration << 8 | altsetting) */
Here and below, you should fit lines into 80 columns. And the closing
*/ should be on a separate line (many people like to put the opening /*
on a separate line too).
Also, the high byte of wIndex is interface, not configuration.
> + if ((requesttype == 0xa1) && (request == 0x00))
Nested parens not needed. And the request value should be given in
decimal, like it is in the spec.
> + {
The open paren should be at the end of the "if" line, not on a line of
its own.
> + alt_setting = usb_find_alt_setting(ps->dev->actconfig, index >> 8, index & 0xff);
> + if (alt_setting && (alt_setting->desc.bInterfaceClass == USB_CLASS_PRINTER))
> + index >>= 8;
> + }
> +
> index &= 0xff;
> switch (requesttype & USB_RECIP_MASK) {
> case USB_RECIP_ENDPOINT:
> @@ -770,7 +780,7 @@ static int proc_control(struct dev_state *ps, void __user *arg)
>
> if (copy_from_user(&ctrl, arg, sizeof(ctrl)))
> return -EFAULT;
> - ret = check_ctrlrecip(ps, ctrl.bRequestType, ctrl.wIndex);
> + ret = check_ctrlrecip(ps, ctrl.bRequestType, ctrl.bRequest, ctrl.wIndex);
> if (ret)
> return ret;
> wLength = ctrl.wLength; /* To suppress 64k PAGE_SIZE warning */
> @@ -1100,7 +1110,7 @@ static int proc_do_submiturb(struct dev_state *ps, struct usbdevfs_urb *uurb,
> kfree(dr);
> return -EINVAL;
> }
> - ret = check_ctrlrecip(ps, dr->bRequestType,
> + ret = check_ctrlrecip(ps, dr->bRequestType, dr->bRequest,
> le16_to_cpup(&dr->wIndex));
> if (ret) {
> kfree(dr);
Alan Stern
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