Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754187AbZG2VgW (ORCPT ); Wed, 29 Jul 2009 17:36:22 -0400 Received: (majordomo@vger.kernel.org) by vger.kernel.org id S1753798AbZG2VgW (ORCPT ); Wed, 29 Jul 2009 17:36:22 -0400 Received: from mail.lang.hm ([64.81.33.126]:46834 "EHLO bifrost.lang.hm" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752555AbZG2VgV (ORCPT ); Wed, 29 Jul 2009 17:36:21 -0400 Date: Wed, 29 Jul 2009 14:35:57 -0700 (PDT) From: david@lang.hm X-X-Sender: dlang@asgard.lang.hm To: "H. Peter Anvin" cc: Greg KH , Alan Stern , Kernel development list , Andrew Morton , alan@lxorguk.ukuu.org.uk Subject: Re: [Security] Should open TTY device files pin minor numbers? In-Reply-To: <4A70BD33.808@zytor.com> Message-ID: References: <20090725051434.GD19432@kroah.com> <4A70BD33.808@zytor.com> User-Agent: Alpine 1.10 (DEB 962 2008-03-14) MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII; format=flowed Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1316 Lines: 31 On Wed, 29 Jul 2009, H. Peter Anvin wrote: > On 07/24/2009 10:14 PM, Greg KH wrote: >> On Thu, Jul 23, 2009 at 02:38:01PM -0400, Alan Stern wrote: >>> Recent work in the TTY core and in usb-serial has caused a change >>> in behavior between 2.6.30 and 2.6.31-rc. Namely, if a USB serial >>> device is unplugged while a process holds the device file open, the >>> minor number won't get reused until the process closes the file. >> >> That's how the usb-serial code always worked, this is nothing new at >> all. >> >>> For example, if you run minicom over /dev/ttyUSB0, unplug the USB >>> device while minicom is running, and then plug it in again before >>> exiting minicom, it will reappear as /dev/ttyUSB1 instead of >>> /dev/ttyUSB0 (which will be gone). >> >> Exactly. People are used to this by now, it shouldn't be a supprise :) >> > > It is, however, a *very* nasty surprise when the USB bus glitches. however since the serial adapters will be re-detected in a random order it's less nasty than cross-connecting devices and applications silently. David Lang -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/