usb gadget: uvc: uvc_request_data::length field must be signed

commit 6f6543f53f9ce136e01d7114bf6f0818ca54fb41 upstream.

The field is used to pass the UVC request data length, but can also be
used to signal an error when setting it to a negative value. Switch from
unsigned int to __s32.

Reported-by: Fernandez Gonzalo <gfernandez@copreci.es>
Signed-off-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>

diff --git a/drivers/usb/gadget/uvc.h b/drivers/usb/gadget/uvc.h
index bc78c60..ca4e03a 100644 (file)
--- a/drivers/usb/gadget/uvc.h
+++ b/drivers/usb/gadget/uvc.h
@@ -28,7 +28,7 @@
 
 struct uvc_request_data
 {
-       unsigned int length;
+       __s32 length;
        __u8 data[60];
 };
 

diff --git a/drivers/usb/gadget/uvc_v4l2.c b/drivers/usb/gadget/uvc_v4l2.c
index f6e083b..54d7ca5 100644 (file)
--- a/drivers/usb/gadget/uvc_v4l2.c
+++ b/drivers/usb/gadget/uvc_v4l2.c
@@ -39,7 +39,7 @@ uvc_send_response(struct uvc_device *uvc, struct uvc_request_data *data)
        if (data->length < 0)
                return usb_ep_set_halt(cdev->gadget->ep0);
 
-       req->length = min(uvc->event_length, data->length);
+       req->length = min_t(unsigned int, uvc->event_length, data->length);
        req->zero = data->length < uvc->event_length;
        req->dma = DMA_ADDR_INVALID;