USB: fix memleak in usbfs

This patch fixes a memory leak in devio.c::processcompl

If writing to user space fails the packet must be discarded, as it
already has been removed from the queue of completed packets.

Signed-off-by: Oliver Neukum <oliver@neukum.org>
Cc: stable <stable@kernel.org>
Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

drivers/usb/core/devio.c

@@ -1231,22 +1231,22 @@ static int processcompl(struct async *as, void __user * __user *arg)
 	if (as->userbuffer)
 		if (copy_to_user(as->userbuffer, urb->transfer_buffer,
 				 urb->transfer_buffer_length))
-			return -EFAULT;
+			goto err_out;
 	if (put_user(as->status, &userurb->status))
-		return -EFAULT;
+		goto err_out;
 	if (put_user(urb->actual_length, &userurb->actual_length))
-		return -EFAULT;
+		goto err_out;
 	if (put_user(urb->error_count, &userurb->error_count))
-		return -EFAULT;
+		goto err_out;
 
 	if (usb_endpoint_xfer_isoc(&urb->ep->desc)) {
 		for (i = 0; i < urb->number_of_packets; i++) {
 			if (put_user(urb->iso_frame_desc[i].actual_length,
 				     &userurb->iso_frame_desc[i].actual_length))
-				return -EFAULT;
+				goto err_out;
 			if (put_user(urb->iso_frame_desc[i].status,
 				     &userurb->iso_frame_desc[i].status))
-				return -EFAULT;
+				goto err_out;
 		}
 	}
 
@@ -1255,6 +1255,10 @@ static int processcompl(struct async *as, void __user * __user *arg)
 	if (put_user(addr, (void __user * __user *)arg))
 		return -EFAULT;
 	return 0;
+
+err_out:
+	free_async(as);
+	return -EFAULT;
 }
 
 static struct async *reap_as(struct dev_state *ps)