usb: gadget: uvc: verify descriptors presence

If the caller of uvc_alloc() does not provide enough
descriptors, binding the function should fail, so appropriate
code is returned from uvc_copy_descriptors().

uvc_function_bind() is modified accordingly to account for possible
errors from uvc_copy_descriptors().

Signed-off-by: Andrzej Pietrasiewicz <andrzej.p@samsung.com>
Acked-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Felipe Balbi <balbi@ti.com>

diff --git a/drivers/usb/gadget/function/f_uvc.c b/drivers/usb/gadget/function/f_uvc.c
index 5b4ab39cce44c8701bad9c8ac02116dedb5d25c1..62ca0c5c7f6e14742380630c9d23a08ddbef5830 100644 (file)
--- a/drivers/usb/gadget/function/f_uvc.c
+++ b/drivers/usb/gadget/function/f_uvc.c
@@ -509,6 +509,9 @@ uvc_copy_descriptors(struct uvc_device *uvc, enum usb_device_speed speed)
                break;
        }
 
+       if (!uvc_control_desc || !uvc_streaming_cls)
+               return ERR_PTR(-ENODEV);
+
        /* Descriptors layout
         *
         * uvc_iad
@@ -700,10 +703,27 @@ uvc_function_bind(struct usb_configuration *c, struct usb_function *f)
 
        /* Copy descriptors */
        f->fs_descriptors = uvc_copy_descriptors(uvc, USB_SPEED_FULL);
-       if (gadget_is_dualspeed(cdev->gadget))
+       if (IS_ERR(f->fs_descriptors)) {
+               ret = PTR_ERR(f->fs_descriptors);
+               f->fs_descriptors = NULL;
+               goto error;
+       }
+       if (gadget_is_dualspeed(cdev->gadget)) {
                f->hs_descriptors = uvc_copy_descriptors(uvc, USB_SPEED_HIGH);
-       if (gadget_is_superspeed(c->cdev->gadget))
+               if (IS_ERR(f->hs_descriptors)) {
+                       ret = PTR_ERR(f->hs_descriptors);
+                       f->hs_descriptors = NULL;
+                       goto error;
+               }
+       }
+       if (gadget_is_superspeed(c->cdev->gadget)) {
                f->ss_descriptors = uvc_copy_descriptors(uvc, USB_SPEED_SUPER);
+               if (IS_ERR(f->ss_descriptors)) {
+                       ret = PTR_ERR(f->ss_descriptors);
+                       f->ss_descriptors = NULL;
+                       goto error;
+               }
+       }
 
        /* Preallocate control endpoint request. */
        uvc->control_req = usb_ep_alloc_request(cdev->gadget->ep0, GFP_KERNEL);