Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753655AbaBSNsY (ORCPT ); Wed, 19 Feb 2014 08:48:24 -0500 Received: from mail-oa0-f43.google.com ([209.85.219.43]:37721 "EHLO mail-oa0-f43.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752883AbaBSNsW (ORCPT ); Wed, 19 Feb 2014 08:48:22 -0500 MIME-Version: 1.0 In-Reply-To: <20140218232702.GA26051@redhat.com> References: <20140218220606.GA9712@redhat.com> <20140218232702.GA26051@redhat.com> Date: Wed, 19 Feb 2014 22:48:21 +0900 Message-ID: Subject: Re: [PATCH] Set bounds on what /proc/self/make-it-fail accepts. From: Akinobu Mita To: Dave Jones , David Rientjes , Akinobu Mita , Linux Kernel , Al Viro Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2014-02-19 8:27 GMT+09:00 Dave Jones : > On Tue, Feb 18, 2014 at 02:32:02PM -0800, David Rientjes wrote: > > On Tue, 18 Feb 2014, Dave Jones wrote: > > > > > /proc/self/make-it-fail is a boolean, but accepts any number, including > > > negative ones. Change variable to unsigned, and cap upper bound at 1. > > > > Hmm, this would break anything that uses anything other than one to enable > > it, but it looks like Documentation/fault-injection/fault-injection.txt > > only provides an example for when it does equal one, so it's probably an > > ok change. I'm just wondering why non-zero is wrong? Is this an > > interface that will be extended to support other modes? > > "Wrong" is perhaps too strong a word, but we only ever check it for non-zero state, > so it seems at best suboptimal to allow strange configurations. > > When I saw I could set it to nonsense values like -1, I figured it could > use some idiot proofing. The lack of any checking at all surprised me. > > Future extension of this interface seems unlikely given the boolean sounding name. > (Though we've done that in the past with things like the overcommit_memory sysctl, > with pretty awful end-user results). I don't have any plans to extend /proc/self/make-it-fail to support other than 0 or 1. So I have no objection against this change. Reviewed-by: Akinobu Mita -- 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/