[v2] usb: raw-gadget: return -EINVAL if no proper ep address available

[PATCH v2] usb: raw-gadget: return -EINVAL if no proper ep address available

Posted by Wei Ming Chen 4 years, 3 months ago

If we try to use raw_ioctl_ep_enable() for ep5in on a hardware that
only support from ep1-ep4 for both in and out direction, it will return
-EBUSY originally.

I think it will be more intuitive if we return -EINVAL, because -EBUSY
sounds like ep5in is not available now, but might be available in the
future.

Signed-off-by: Wei Ming Chen <jj251510319013@gmail.com>
---

Changes in v2:
- Rename variable from ep_num_matched to ep_props_matched
- Incorporate the patch from Andrey Konovalov that cover
  the foloowing cases:
    1. If there are no endpoints that match the provided descriptor, return
       EINVAL.
    2. If there are matching endpoints, but they are all already enabled,
       return EBUSY.

 drivers/usb/gadget/legacy/raw_gadget.c | 15 +++++++++++----
 1 file changed, 11 insertions(+), 4 deletions(-)

diff --git a/drivers/usb/gadget/legacy/raw_gadget.c b/drivers/usb/gadget/legacy/raw_gadget.c
index d86c3a36441e..e5707626c4d4 100644
--- a/drivers/usb/gadget/legacy/raw_gadget.c
+++ b/drivers/usb/gadget/legacy/raw_gadget.c
@@ -758,6 +758,7 @@ static int raw_ioctl_ep_enable(struct raw_dev *dev, unsigned long value)
 	unsigned long flags;
 	struct usb_endpoint_descriptor *desc;
 	struct raw_ep *ep;
+	bool ep_props_matched = false;
 
 	desc = memdup_user((void __user *)value, sizeof(*desc));
 	if (IS_ERR(desc))
@@ -787,13 +788,14 @@ static int raw_ioctl_ep_enable(struct raw_dev *dev, unsigned long value)
 
 	for (i = 0; i < dev->eps_num; i++) {
 		ep = &dev->eps[i];
-		if (ep->state != STATE_EP_DISABLED)
-			continue;
 		if (ep->addr != usb_endpoint_num(desc) &&
 				ep->addr != USB_RAW_EP_ADDR_ANY)
 			continue;
 		if (!usb_gadget_ep_match_desc(dev->gadget, ep->ep, desc, NULL))
 			continue;
+		ep_props_matched = true;
+		if (ep->state != STATE_EP_DISABLED)
+			continue;
 		ep->ep->desc = desc;
 		ret = usb_ep_enable(ep->ep);
 		if (ret < 0) {
@@ -815,8 +817,13 @@ static int raw_ioctl_ep_enable(struct raw_dev *dev, unsigned long value)
 		goto out_unlock;
 	}
 
-	dev_dbg(&dev->gadget->dev, "fail, no gadget endpoints available\n");
-	ret = -EBUSY;
+	if (!ep_props_matched) {
+		dev_dbg(&dev->gadget->dev, "fail, bad endpoint descriptor\n");
+		ret = -EINVAL;
+	} else {
+		dev_dbg(&dev->gadget->dev, "fail, no endpoints available\n");
+		ret = -EBUSY;
+	}
 
 out_free:
 	kfree(desc);
-- 
2.25.1

Re: [PATCH v2] usb: raw-gadget: return -EINVAL if no proper ep address available

Posted by Andrey Konovalov 4 years, 3 months ago

On Fri, Mar 11, 2022 at 9:30 AM Wei Ming Chen <jj251510319013@gmail.com> wrote:
>
> If we try to use raw_ioctl_ep_enable() for ep5in on a hardware that
> only support from ep1-ep4 for both in and out direction, it will return
> -EBUSY originally.
>
> I think it will be more intuitive if we return -EINVAL, because -EBUSY
> sounds like ep5in is not available now, but might be available in the
> future.
>
> Signed-off-by: Wei Ming Chen <jj251510319013@gmail.com>
> ---
>
> Changes in v2:
> - Rename variable from ep_num_matched to ep_props_matched
> - Incorporate the patch from Andrey Konovalov that cover
>   the foloowing cases:
>     1. If there are no endpoints that match the provided descriptor, return
>        EINVAL.
>     2. If there are matching endpoints, but they are all already enabled,
>        return EBUSY.
>
>  drivers/usb/gadget/legacy/raw_gadget.c | 15 +++++++++++----
>  1 file changed, 11 insertions(+), 4 deletions(-)
>
> diff --git a/drivers/usb/gadget/legacy/raw_gadget.c b/drivers/usb/gadget/legacy/raw_gadget.c
> index d86c3a36441e..e5707626c4d4 100644
> --- a/drivers/usb/gadget/legacy/raw_gadget.c
> +++ b/drivers/usb/gadget/legacy/raw_gadget.c
> @@ -758,6 +758,7 @@ static int raw_ioctl_ep_enable(struct raw_dev *dev, unsigned long value)
>         unsigned long flags;
>         struct usb_endpoint_descriptor *desc;
>         struct raw_ep *ep;
> +       bool ep_props_matched = false;
>
>         desc = memdup_user((void __user *)value, sizeof(*desc));
>         if (IS_ERR(desc))
> @@ -787,13 +788,14 @@ static int raw_ioctl_ep_enable(struct raw_dev *dev, unsigned long value)
>
>         for (i = 0; i < dev->eps_num; i++) {
>                 ep = &dev->eps[i];
> -               if (ep->state != STATE_EP_DISABLED)
> -                       continue;
>                 if (ep->addr != usb_endpoint_num(desc) &&
>                                 ep->addr != USB_RAW_EP_ADDR_ANY)
>                         continue;
>                 if (!usb_gadget_ep_match_desc(dev->gadget, ep->ep, desc, NULL))
>                         continue;
> +               ep_props_matched = true;
> +               if (ep->state != STATE_EP_DISABLED)
> +                       continue;
>                 ep->ep->desc = desc;
>                 ret = usb_ep_enable(ep->ep);
>                 if (ret < 0) {
> @@ -815,8 +817,13 @@ static int raw_ioctl_ep_enable(struct raw_dev *dev, unsigned long value)
>                 goto out_unlock;
>         }
>
> -       dev_dbg(&dev->gadget->dev, "fail, no gadget endpoints available\n");
> -       ret = -EBUSY;
> +       if (!ep_props_matched) {
> +               dev_dbg(&dev->gadget->dev, "fail, bad endpoint descriptor\n");
> +               ret = -EINVAL;
> +       } else {
> +               dev_dbg(&dev->gadget->dev, "fail, no endpoints available\n");
> +               ret = -EBUSY;
> +       }
>
>  out_free:
>         kfree(desc);
> --
> 2.25.1
>

Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>

Greg, could you consider picking this up?

Thanks!

Re: [PATCH v2] usb: raw-gadget: return -EINVAL if no proper ep address available

Posted by Greg Kroah-Hartman 4 years, 3 months ago

On Sun, Mar 13, 2022 at 03:52:35PM +0100, Andrey Konovalov wrote:
> On Fri, Mar 11, 2022 at 9:30 AM Wei Ming Chen <jj251510319013@gmail.com> wrote:
> >
> > If we try to use raw_ioctl_ep_enable() for ep5in on a hardware that
> > only support from ep1-ep4 for both in and out direction, it will return
> > -EBUSY originally.
> >
> > I think it will be more intuitive if we return -EINVAL, because -EBUSY
> > sounds like ep5in is not available now, but might be available in the
> > future.
> >
> > Signed-off-by: Wei Ming Chen <jj251510319013@gmail.com>
> > ---
> >
> > Changes in v2:
> > - Rename variable from ep_num_matched to ep_props_matched
> > - Incorporate the patch from Andrey Konovalov that cover
> >   the foloowing cases:
> >     1. If there are no endpoints that match the provided descriptor, return
> >        EINVAL.
> >     2. If there are matching endpoints, but they are all already enabled,
> >        return EBUSY.
> >
> >  drivers/usb/gadget/legacy/raw_gadget.c | 15 +++++++++++----
> >  1 file changed, 11 insertions(+), 4 deletions(-)
> >
> > diff --git a/drivers/usb/gadget/legacy/raw_gadget.c b/drivers/usb/gadget/legacy/raw_gadget.c
> > index d86c3a36441e..e5707626c4d4 100644
> > --- a/drivers/usb/gadget/legacy/raw_gadget.c
> > +++ b/drivers/usb/gadget/legacy/raw_gadget.c
> > @@ -758,6 +758,7 @@ static int raw_ioctl_ep_enable(struct raw_dev *dev, unsigned long value)
> >         unsigned long flags;
> >         struct usb_endpoint_descriptor *desc;
> >         struct raw_ep *ep;
> > +       bool ep_props_matched = false;
> >
> >         desc = memdup_user((void __user *)value, sizeof(*desc));
> >         if (IS_ERR(desc))
> > @@ -787,13 +788,14 @@ static int raw_ioctl_ep_enable(struct raw_dev *dev, unsigned long value)
> >
> >         for (i = 0; i < dev->eps_num; i++) {
> >                 ep = &dev->eps[i];
> > -               if (ep->state != STATE_EP_DISABLED)
> > -                       continue;
> >                 if (ep->addr != usb_endpoint_num(desc) &&
> >                                 ep->addr != USB_RAW_EP_ADDR_ANY)
> >                         continue;
> >                 if (!usb_gadget_ep_match_desc(dev->gadget, ep->ep, desc, NULL))
> >                         continue;
> > +               ep_props_matched = true;
> > +               if (ep->state != STATE_EP_DISABLED)
> > +                       continue;
> >                 ep->ep->desc = desc;
> >                 ret = usb_ep_enable(ep->ep);
> >                 if (ret < 0) {
> > @@ -815,8 +817,13 @@ static int raw_ioctl_ep_enable(struct raw_dev *dev, unsigned long value)
> >                 goto out_unlock;
> >         }
> >
> > -       dev_dbg(&dev->gadget->dev, "fail, no gadget endpoints available\n");
> > -       ret = -EBUSY;
> > +       if (!ep_props_matched) {
> > +               dev_dbg(&dev->gadget->dev, "fail, bad endpoint descriptor\n");
> > +               ret = -EINVAL;
> > +       } else {
> > +               dev_dbg(&dev->gadget->dev, "fail, no endpoints available\n");
> > +               ret = -EBUSY;
> > +       }
> >
> >  out_free:
> >         kfree(desc);
> > --
> > 2.25.1
> >
> 
> Reviewed-by: Andrey Konovalov <andreyknvl@gmail.com>
> 
> Greg, could you consider picking this up?

Now picked up, thanks.

greg k-h