Hi,

On 10/04/2013 05:44 PM, Alan Stern wrote:
On Fri, 4 Oct 2013, Hans de Goede wrote:

+static int parse_usbdevfs_streams(struct usb_device *dev,
+                                 struct usbdevfs_streams __user *streams,
+                                 unsigned int *num_streams_ret,
+                                 unsigned int *num_eps_ret,
+                                 struct usb_host_endpoint ***eps_ret,
+                                 struct usb_interface **intf_ret)
+{
+       unsigned int i, num_streams, num_eps;
+       struct usb_host_endpoint **eps;
+       struct usb_interface *intf = NULL;
+       unsigned char ep;
+       int ret;
+
+       if (get_user(num_streams, &streams->num_streams) ||
+           get_user(num_eps, &streams->num_eps))
+               return -EFAULT;
+
+       if (num_eps < 1 || num_eps > USB_MAXENDPOINTS)
+               return -EINVAL;
+
+       /* The XHCI controller allows max 1024 streams */
+       if (num_streams_ret && (num_streams < 2 || num_streams > 1024))
+               return -EINVAL;
+
+       eps = kmalloc(num_eps * sizeof(*eps), GFP_KERNEL);
+       if (!eps)
+               return -ENOMEM;
+
+       for (i = 0; i < num_eps; i++) {
+               if (get_user(ep, &streams->eps[i])) {
+                       ret = -EFAULT;
+                       goto error;
+               }
+               eps[i] = ep_to_host_endpoint(dev, ep);
+               if (!eps[i]) {
+                       ret = -EINVAL;
+                       goto error;
+               }
+
+               /* usb_alloc/free_streams operate on an usb_interface */
+               ret = findintfep(dev, ep);
+               if (ret < 0)
+                       goto error;
+
+               if (i == 0) {
+                       intf = usb_ifnum_to_if(dev, ret);
+               } else {
+                       /* Verify all eps belong to the same interface */
+                       if (ret != intf->altsetting->desc.bInterfaceNumber) {
+                               ret = -EINVAL;
+                               goto error;
+                       }
+               }
+       }
+
+       if (num_streams_ret)
+               *num_streams_ret = num_streams;
+       *num_eps_ret = num_eps;
+       *eps_ret = eps;
+       *intf_ret = intf;
+
+       return 0;
+
+error:
+       kfree(eps);
+       return ret;
+}

Somewhere in here you should check that the caller has claimed the
interface containing these endpoints.

Yes, good point. Will fix in next revision.

Regards,

Hans
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