From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751473AbcGPJjG (ORCPT ); Sat, 16 Jul 2016 05:39:06 -0400 Received: from mail.avalus.com ([89.16.176.221]:39173 "EHLO mail.avalus.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751384AbcGPJjE convert rfc822-to-8bit (ORCPT ); Sat, 16 Jul 2016 05:39:04 -0400 X-Greylist: delayed 408 seconds by postgrey-1.27 at vger.kernel.org; Sat, 16 Jul 2016 05:39:03 EDT Content-Type: text/plain; charset=us-ascii Mime-Version: 1.0 (Mac OS X Mail 7.3 \(1878.6\)) Subject: Re: [Nbd] [PATCH 2/2] nbd: Disallow ioctls on disconnected block device From: Alex Bligh In-Reply-To: Date: Sat, 16 Jul 2016 10:32:11 +0100 Cc: Alex Bligh , Markus Pargmann , "nbd-general@lists.sourceforge.net" , Wouter Verhelst , "linux-kernel@vger.kernel.org" Content-Transfer-Encoding: 8BIT Message-Id: References: <1466760574-1916-1-git-send-email-mpa@pengutronix.de> <1466760574-1916-2-git-send-email-mpa@pengutronix.de> To: Pranay Srivastava X-Mailer: Apple Mail (2.1878.6) Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 16 Jul 2016, at 08:42, Pranay Srivastava wrote: > So instead can't we put a mechanism in place for network address + mac > to be same > for allowing clients to reconnect? Do let me know if this is not of concern. MAC address?! nbd clients connect over IP, and if a router reboots between them, you could easily see two packets from the same client come from different MAC addresses. Similarly all clients not on the same L2 network will carry the same MAC address. So MAC address is a very poor indicator of 'same client'. IP address is also a poor indicator (think NAT) but is substantially less bad. -- Alex Bligh