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=-6.1 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,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 4E3CAC433F5 for ; Mon, 6 Sep 2021 17:19:17 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 2573861004 for ; Mon, 6 Sep 2021 17:19:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S234305AbhIFRUU (ORCPT ); Mon, 6 Sep 2021 13:20:20 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:43314 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S243797AbhIFRUS (ORCPT ); Mon, 6 Sep 2021 13:20:18 -0400 Received: from mail-pf1-x431.google.com (mail-pf1-x431.google.com [IPv6:2607:f8b0:4864:20::431]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 8604AC061757 for ; Mon, 6 Sep 2021 10:19:13 -0700 (PDT) Received: by mail-pf1-x431.google.com with SMTP id f65so2496984pfb.10 for ; Mon, 06 Sep 2021 10:19:13 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=0w5VvMqvVfXA2u97tXNbjwUCVgURBwlqEz+ps2g78yU=; b=i+gmhVx9C6mf17aSAk5OQCGeo7nx9y7t1WQxvx78PMr2GOEUBoRG792pvZdPHPxGfR Y5C8ydKE4AiyPQ3fw9PHfdijisiHdLJxIVab71COe6/2o3opCzeObHVfIchUMoyz4X1T ml0Fs874tXkPBMzuWApZHVS69gYQArVNQr2vQ= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=0w5VvMqvVfXA2u97tXNbjwUCVgURBwlqEz+ps2g78yU=; b=fGk4MAyqy/0Z0V34JHDb08UTal4uZEJXy/ADsc4HYV/jmDo9UdphDsgi/DWgN0pjX4 oMqk8SgtG1nrWR2ZxLUN0KHqEsezz63xhU08Ohyr8tjBzKoNBqnDUPkrsJC0SGZ/xSV7 +x62UNoutFDBaTMqaoCAB01xM7LZyisKDBM3NSjLLzulywrhlo1yPQT5D2vENNCm0PWx IL+xgf2xFWMpkJVsbkSL8h/NuhPCJbiuLOf2fJ7UqMvlfT72e/23SqfQHcQCY9DiJ04z j+Sqwxm8TrSkOO4w7WtBY9PLwHLVhUoucR5k1oOSW6CPJcjQLdgNCKGUPEGOTS7uXbUg /8Lw== X-Gm-Message-State: AOAM533cfG2tf7dR2aYqlS6DiwcyhpJVZM8tjfZ4Z/0Fp9q3iCr6OzI7 7YsTty+zMwvxkk+UBkWsHHRXQw== X-Google-Smtp-Source: ABdhPJyFnrCQ63UYWsWdIVntYuP7YvJFdaF08GSZvaAN1C8w70OlxJOprKmL15JsdS3e07d3SHvEFg== X-Received: by 2002:a05:6a00:2352:b0:40b:2031:4827 with SMTP id j18-20020a056a00235200b0040b20314827mr17280299pfj.6.1630948752993; Mon, 06 Sep 2021 10:19:12 -0700 (PDT) Received: from www.outflux.net (smtp.outflux.net. [198.145.64.163]) by smtp.gmail.com with ESMTPSA id d200sm8208350pfd.127.2021.09.06.10.19.12 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Mon, 06 Sep 2021 10:19:12 -0700 (PDT) Date: Mon, 6 Sep 2021 10:19:11 -0700 From: Kees Cook To: Mark Brown Cc: Linus Torvalds , Linux Kernel Mailing List , Arnd Bergmann , Daniel Vetter , Dan Williams , Rasmus Villemoes , Greg Kroah-Hartman , "Gustavo A. R. Silva" , Keith Packard , Nathan Chancellor , Nick Desaulniers , linux-hardening@vger.kernel.org Subject: Re: [GIT PULL] overflow updates for v5.15-rc1 Message-ID: <202109061013.E4730B3B42@keescook> References: <202109022012.756B6B5B79@keescook> <45312958-B844-4B4C-9808-8205866675A1@chromium.org> <202109051123.11E4E31@keescook> <20210906114350.GB4309@sirena.org.uk> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210906114350.GB4309@sirena.org.uk> Precedence: bulk List-ID: X-Mailing-List: linux-hardening@vger.kernel.org On Mon, Sep 06, 2021 at 12:43:50PM +0100, Mark Brown wrote: > If you're looking for coverage on this stuff it's also good to check > with clang as well, it's sufficiently different that it often triggers > extra stuff [...] Yup, I tested across multiple GCC and Clang versions, which is why the failures came as such a surprise. And specifically, these overflow changes have been designed with Clang in mind (as well as GCC obviously). (i.e. see the patch[0] in this series, and the last patch[1] in the coming series.) -Kees [0] https://lore.kernel.org/lkml/20210822075122.864511-17-keescook@chromium.org/ [1] https://lore.kernel.org/lkml/20210818060533.3569517-64-keescook@chromium.org/ -- Kees Cook