USB: serial: io_edgeport: fix memory leak in edge_startup

sysbot found memory leak in edge_startup().
The problem was that when an error was received from the usb_submit_urb(),
nothing was cleaned up.

Reported-by: syzbot+59f777bdcbdd7eea5305@syzkaller.appspotmail.com
Signed-off-by: Pavel Skripkin <paskripkin@gmail.com>
Fixes: 6e8cf77 ("USB: add EPIC support to the io_edgeport driver")
Cc: stable@vger.kernel.org	# 2.6.21: c5c0c55
Signed-off-by: Johan Hovold <johan@kernel.org>

Author: pskrgag

drivers/usb/serial/io_edgeport.c

@@ -3003,26 +3003,32 @@ static int edge_startup(struct usb_serial *serial)
 				response = -ENODEV;
 			}
 
-			usb_free_urb(edge_serial->interrupt_read_urb);
-			kfree(edge_serial->interrupt_in_buffer);
-
-			usb_free_urb(edge_serial->read_urb);
-			kfree(edge_serial->bulk_in_buffer);
-
-			kfree(edge_serial);
-
-			return response;
+			goto error;
 		}
 
 		/* start interrupt read for this edgeport this interrupt will
 		 * continue as long as the edgeport is connected */
 		response = usb_submit_urb(edge_serial->interrupt_read_urb,
 								GFP_KERNEL);
-		if (response)
+		if (response) {
 			dev_err(ddev, "%s - Error %d submitting control urb\n",
 				__func__, response);
+
+			goto error;
+		}
 	}
 	return response;
+
+error:
+	usb_free_urb(edge_serial->interrupt_read_urb);
+	kfree(edge_serial->interrupt_in_buffer);
+
+	usb_free_urb(edge_serial->read_urb);
+	kfree(edge_serial->bulk_in_buffer);
+
+	kfree(edge_serial);
+
+	return response;
 }