From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1754177AbbCIKBU (ORCPT ); Mon, 9 Mar 2015 06:01:20 -0400 Received: from mail-wi0-f175.google.com ([209.85.212.175]:43483 "EHLO mail-wi0-f175.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753619AbbCIKBQ (ORCPT ); Mon, 9 Mar 2015 06:01:16 -0400 Message-ID: <54FD6F68.2010708@suse.cz> Date: Mon, 09 Mar 2015 11:01:12 +0100 From: Jiri Slaby User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:31.0) Gecko/20100101 Thunderbird/31.5.0 MIME-Version: 1.0 To: Raymond Jennings CC: gregkh@linuxfoundation.org, linux-kernel@vger.kernel.org, john_paul.perry@alcatel-lucent.com, stable@vger.kernel.org, Linus Torvalds Subject: Re: [PATCH 1/1] tty: fix up atime/mtime mess, take four References: <1425058831-13923-1-git-send-email-jslaby@suse.cz> <1425647774.14441.1.camel@avalar.dragonrealms> In-Reply-To: <1425647774.14441.1.camel@avalar.dragonrealms> Content-Type: text/plain; charset=utf-8 Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 03/06/2015, 02:16 PM, Raymond Jennings wrote: > On Fri, 2015-02-27 at 18:40 +0100, Jiri Slaby wrote: >> So check the absolute difference of times and if it large than "8 >> seconds or so", always update the time. That means we will update >> immediatelly when changing time. Ergo, CAP_SYS_TIME can foul the >> check, but it was always that way. > > If I may ask, what is supposed to happen normally when you write to a > tty device? I always thought the tty device was treated just like a > normal file wrt. timestamps. > > Now I see a patch for 8 seconds something. Yes, because you do not want to be given any clue when users are typing passwords. You could intercept the length of the password from the pauses between key strokes (tty timestamps). thanks, -- js suse labs