From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932211Ab2BVEUQ (ORCPT ); Tue, 21 Feb 2012 23:20:16 -0500 Received: from out5-smtp.messagingengine.com ([66.111.4.29]:58001 "EHLO out5-smtp.messagingengine.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932177Ab2BVEUP (ORCPT ); Tue, 21 Feb 2012 23:20:15 -0500 X-Sasl-enc: cUMNeD4DthQyf9U6T+P3LhLNgOlAmIa8MdkoI6yoqcGA2U4Lq8FHL4jBjg 1329884413 Message-ID: <1329884410.2193.29.camel@perseus.themaw.net> Subject: Re: compat: autofs v5 packet size ambiguity - update From: Ian Kent To: Linus Torvalds Cc: David Miller , linux-kernel@vger.kernel.org, hpa@zytor.com, autofs@linux.kernel.org, thomas@m3y3r.de, viro@zeniv.linux.org.uk Date: Wed, 22 Feb 2012 12:20:10 +0800 In-Reply-To: References: <20120221.221609.218135609185671883.davem@davemloft.net> Content-Type: text/plain; charset="UTF-8" X-Mailer: Evolution 3.2.3 (3.2.3-1.fc16) Content-Transfer-Encoding: 7bit Mime-Version: 1.0 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Tue, 2012-02-21 at 19:47 -0800, Linus Torvalds wrote: > On Tue, Feb 21, 2012 at 7:33 PM, Linus Torvalds > wrote: > > > > But I'm sure that the autofs daemon does something simple that we can > > depend on in practice. > > I didn't find the most recent source code, but the first thing that > automount.c does after calling "mount" (which is a for+exec, so we > cannot take the mounting is_compat_task() into account is to open the > new root for the ioctlfd, and then it does a stat. > > And then it does a AUTOFS_IOC_PROTOVER ioctl to see what the protocol > version is. > > So we could just decide that > > (a) we add a mount option for the packet size (or just "v6" - which > would be "v5 with a fixed packet size") > > (b) in the absence of an explicit mount option, we look at > is_compat_task() for the first AUTOFS_IOC_PROTOVER ioctl we get. > > That looks fairly straightforward and safe. Hmm? > > Where are the automount sources supposed to be, anyway? kernel.org has > a v5 directory, but it's empty. I'm repopulating the autofs directory with content right now. I had some difficulty with getting appropriate signatures for my PGP key, consequently my account wasn't activated for quite. The upshot of that is I wasn't aware of announcements about kup either. Anyway, I've sorted that out and I'm trying to upload the content right now. The git repo has been available for a while now though @ /pub/scm/linux/kernel/git/raven/autofs at least that is the place I thought it should go? Ian