From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-2.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,FREEMAIL_FORGED_FROMDOMAIN,FREEMAIL_FROM, HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS autolearn=no autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id A9334C83013 for ; Sun, 22 Nov 2020 20:36:37 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 6DD4D20782 for ; Sun, 22 Nov 2020 20:36:37 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (2048-bit key) header.d=gmail.com header.i=@gmail.com header.b="tX7AFJY3" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727719AbgKVUgL (ORCPT ); Sun, 22 Nov 2020 15:36:11 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50712 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727637AbgKVUgK (ORCPT ); Sun, 22 Nov 2020 15:36:10 -0500 Received: from mail-yb1-xb34.google.com (mail-yb1-xb34.google.com [IPv6:2607:f8b0:4864:20::b34]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 65ADFC0613CF; Sun, 22 Nov 2020 12:36:10 -0800 (PST) Received: by mail-yb1-xb34.google.com with SMTP id g15so14049320ybq.6; Sun, 22 Nov 2020 12:36:10 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20161025; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=GG13N+h9bYKW0tA8PzZdEh0PqD5/qSPuWfMm4/MLZZE=; b=tX7AFJY3IoP+sTWjLWjwUeA0EiMqyjgmEMGUK52Uheybmur4GieXYHjq/4452d4+Q2 I9IJc2W+KgP7eM5cLMrffBSaL1fq5VPLYq7a7Nqy7aqiJs+SWc7hYJy9lsWlIs20dLH2 W28Iwaw2K1E1/9bR59jMmk/7Gq8vv14a82SqbrX8Cr26/AWqo5ergIUL6PfX6EI1DxrF H3tDAymEGdy6lnWgT39rAP3JOfP6UnfKa9FSSCeE7ggKiNT9+2hZ/9zdGiTOU+6HH+d5 TmFQQAuEaRP9Z2Bh9bU0txdUhaZCbT+Ezs+qExtvq1zOJlrZzRYF6kJpZnKXIPWyTN/2 bJqw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:mime-version:references:in-reply-to:from:date :message-id:subject:to:cc; bh=GG13N+h9bYKW0tA8PzZdEh0PqD5/qSPuWfMm4/MLZZE=; b=ObaZf8pj5VtvDEogGRFMCRClpQMF1vhpF/ASZBGDR2ZMFPBkdlpobUU8gm+iGheaSZ ns2+N8dnF+TmQRtMPogwSxF7N8SLrKtcxLjXbvPj4DcS553z4OJ61Ogch9coMHmZ4Rsq 6CPbzxPdfeqRAoDAKy50+BfvqZjsz5eqh3aVSuR2gC7PDJvdZtJxQ2muEGXDCJ40rypk jILpBRDgbW4Z/koTgoC7BhoWSJQOvC8dDrHiWqNZs5sB/BgDPEpDMyacvXBXAGQTzIfY +1aSB0mfzr4Uq1cEv54VG0oDqFZLJAlVLXkYd/LevMeie0/HMexwI8sl1+WQ41CzXpGS 4iCA== X-Gm-Message-State: AOAM533NuDa+35dARUwFwORCkHM2dODSzVByVhRP4hgefPlm7KOc6ZFl h4MWXQj7WPd+iOpmo5r9qeTUFHedV1cn1RmnU3A= X-Google-Smtp-Source: ABdhPJzCLkP7XKvI+ogPcqXNjFlbBz0ulixnxLa8L+LTJiC1sb757UHHSouM0vJ9LX/4+Ocy8hzM6Anb9s4lPpy7cZY= X-Received: by 2002:a25:6986:: with SMTP id e128mr4956056ybc.93.1606077369721; Sun, 22 Nov 2020 12:36:09 -0800 (PST) MIME-Version: 1.0 References: <20201120105344.4345c14e@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com> <202011201129.B13FDB3C@keescook> <20201120115142.292999b2@kicinski-fedora-pc1c0hjn.dhcp.thefacebook.com> <202011220816.8B6591A@keescook> <9b57fd4914b46f38d54087d75e072d6e947cb56d.camel@HansenPartnership.com> In-Reply-To: <9b57fd4914b46f38d54087d75e072d6e947cb56d.camel@HansenPartnership.com> From: Miguel Ojeda Date: Sun, 22 Nov 2020 21:35:58 +0100 Message-ID: Subject: Re: [PATCH 000/141] Fix fall-through warnings for Clang To: James Bottomley Cc: Kees Cook , Jakub Kicinski , "Gustavo A. R. Silva" , linux-kernel , alsa-devel@alsa-project.org, amd-gfx@lists.freedesktop.org, bridge@lists.linux-foundation.org, ceph-devel@vger.kernel.org, cluster-devel@redhat.com, coreteam@netfilter.org, devel@driverdev.osuosl.org, dm-devel@redhat.com, drbd-dev@lists.linbit.com, dri-devel@lists.freedesktop.org, GR-everest-linux-l2@marvell.com, GR-Linux-NIC-Dev@marvell.com, intel-gfx@lists.freedesktop.org, intel-wired-lan@lists.osuosl.org, keyrings@vger.kernel.org, linux1394-devel@lists.sourceforge.net, linux-acpi@vger.kernel.org, linux-afs@lists.infradead.org, Linux ARM , linux-arm-msm@vger.kernel.org, linux-atm-general@lists.sourceforge.net, linux-block@vger.kernel.org, linux-can@vger.kernel.org, linux-cifs@vger.kernel.org, Linux Crypto Mailing List , linux-decnet-user@lists.sourceforge.net, Ext4 Developers List , linux-fbdev@vger.kernel.org, linux-geode@lists.infradead.org, linux-gpio@vger.kernel.org, linux-hams@vger.kernel.org, linux-hwmon@vger.kernel.org, linux-i3c@lists.infradead.org, linux-ide@vger.kernel.org, linux-iio@vger.kernel.org, linux-input , linux-integrity@vger.kernel.org, linux-mediatek@lists.infradead.org, Linux Media Mailing List , linux-mmc@vger.kernel.org, Linux-MM , linux-mtd@lists.infradead.org, linux-nfs@vger.kernel.org, linux-rdma@vger.kernel.org, linux-renesas-soc@vger.kernel.org, linux-scsi@vger.kernel.org, linux-sctp@vger.kernel.org, linux-security-module@vger.kernel.org, linux-stm32@st-md-mailman.stormreply.com, linux-usb@vger.kernel.org, linux-watchdog@vger.kernel.org, linux-wireless , Network Development , netfilter-devel@vger.kernel.org, nouveau@lists.freedesktop.org, op-tee@lists.trustedfirmware.org, oss-drivers@netronome.com, patches@opensource.cirrus.com, rds-devel@oss.oracle.com, reiserfs-devel@vger.kernel.org, samba-technical@lists.samba.org, selinux@vger.kernel.org, target-devel@vger.kernel.org, tipc-discussion@lists.sourceforge.net, usb-storage@lists.one-eyed-alien.net, virtualization@lists.linux-foundation.org, wcn36xx@lists.infradead.org, "maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)" , xen-devel@lists.xenproject.org, linux-hardening@vger.kernel.org, Nick Desaulniers , Nathan Chancellor , Miguel Ojeda , Joe Perches Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-hardening@vger.kernel.org On Sun, Nov 22, 2020 at 7:22 PM James Bottomley wrote: > > Well, it's a problem in an error leg, sure, but it's not a really > compelling reason for a 141 patch series, is it? All that fixing this > error will do is get the driver to print "oh dear there's a problem" > under four more conditions than it previously did. > > We've been at this for three years now with nearly a thousand patches, > firstly marking all the fall throughs with /* fall through */ and later > changing it to fallthrough. At some point we do have to ask if the > effort is commensurate with the protection afforded. Please tell me > our reward for all this effort isn't a single missing error print. It isn't that much effort, isn't it? Plus we need to take into account the future mistakes that it might prevent, too. So even if there were zero problems found so far, it is still a positive change. I would agree if these changes were high risk, though; but they are almost trivial. Cheers, Miguel