Received: by 2002:a05:6358:9144:b0:117:f937:c515 with SMTP id r4csp2158344rwr; Fri, 28 Apr 2023 06:59:16 -0700 (PDT) X-Google-Smtp-Source: ACHHUZ4YX12l9n9KL69YgSsSsGkxf2LQjZe1A58loh75gG9h4eh3w6yZjVH9J3gmrRfGNFmwUKHg X-Received: by 2002:a05:6a21:918c:b0:c6:c0c1:b1fe with SMTP id tp12-20020a056a21918c00b000c6c0c1b1femr5308117pzb.57.1682690356141; Fri, 28 Apr 2023 06:59:16 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1682690356; cv=none; d=google.com; s=arc-20160816; b=wRzlkK84vd1YbPHkT21v52WhbmlDfg59XEXHujcjf5dkDXAaG142aHhUkgfSO6QpGg fUbkyVD59h6Yp0beErwnHLRHKkQcrSUqcwgQRysJGltymqODvKpEmlLbnn5PHrDmuTaG zUdwv+AdiNia7ZlKjq3mz46l3EeAdDZHjVpHN7gm1axknJSTg908t4Xd4WMqcfMCDTq1 TiT5X5dWkszHKTDcJayFRGvU61Pgmrxp34zuDgDehvOV7l+xY4W8nQ+e+qFUXkSIUCCS ZJgfmnk5NY373/yzzPbWaAOjMjSdNYBqD+214zrUFH/SEEmeFixdEGjsippI9z4LMB6x HWww== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:cc:to:subject:message-id:date:from:in-reply-to :references:mime-version:dkim-signature; bh=K1hIAJ3PDs1STD5Nf5EOLfCuqukCGdV5NWCw8Nh61NE=; b=NuGwrq4ahIkFmZ1ShYiuvXIUdAJYaXrQNO2W+HEFysKndzNYvBCjvLMNcZP83TDtrU R3WZZB5x07SNoSsFZnGlcChhl+0Vw0P9xHeQb3s/l4eTUcPBsYiKlRANQy1yRBESunfT kd3zOc7QfRdZm15OwmUwVtAznIk0g3oo5YU/AAM06m0GmCODvixNHZRWvStqD02SG6zJ 8Sl+rTemXWX+Ul8ci+Q5Z1oo7hJXm2mF0KFWIdk8UnYK1ASIFZnLXkMbfrGLKsE7HPe4 EjSXy/UuU2plUbfYPDyLpt2l0Ikp3KHYXZPTHUktsnCE+ffpwD2Z8rTybgsX0VCuuhdC hsgg== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@google.com header.s=20221208 header.b=f3+M7QDL; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=google.com Return-Path: Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id r17-20020aa79891000000b0063b5875dd22si18834984pfl.308.2023.04.28.06.59.02; Fri, 28 Apr 2023 06:59:16 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@google.com header.s=20221208 header.b=f3+M7QDL; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=REJECT sp=REJECT dis=NONE) header.from=google.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1346353AbjD1NtM (ORCPT + 99 others); Fri, 28 Apr 2023 09:49:12 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50828 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1346205AbjD1NtL (ORCPT ); Fri, 28 Apr 2023 09:49:11 -0400 Received: from mail-yb1-xb2d.google.com (mail-yb1-xb2d.google.com [IPv6:2607:f8b0:4864:20::b2d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 13EA11FEB for ; Fri, 28 Apr 2023 06:49:09 -0700 (PDT) Received: by mail-yb1-xb2d.google.com with SMTP id 3f1490d57ef6-b97ec4bbc5aso7942497276.3 for ; Fri, 28 Apr 2023 06:49:09 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=20221208; t=1682689748; x=1685281748; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:from:to:cc:subject:date:message-id:reply-to; bh=K1hIAJ3PDs1STD5Nf5EOLfCuqukCGdV5NWCw8Nh61NE=; b=f3+M7QDLI2K3jtQKfqNELdarX3fK2oxPoOnWILM3KM+kk/9ndNXsaH8G0Tq2fIon1k lscXXpxJfHhxZVJ756aRWAUl2uKFfaBBccBkxMukat/IgzIMi49CwVd9kyPf39VnX6z5 8soeywYZ6HvEirTn/Qu0bQ9bt2NCVZYCMsDGhwbzv5bdUUTng5abmcUZOgGi6XUgwW4F nvjF4onfIXm7+rK+HgvEICQocWjQaAfZVl/hN3wAil7RUq2cMDnLIUFu/45OPvPbeR+R fZ+dEFnacgszupM2mF/H4X6nBsNg4cG1pIs0PprvKCNf1WhHB50fou5fy2LP0IDO3970 MS5A== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1682689748; x=1685281748; h=cc:to:subject:message-id:date:from:in-reply-to:references :mime-version:x-gm-message-state:from:to:cc:subject:date:message-id :reply-to; bh=K1hIAJ3PDs1STD5Nf5EOLfCuqukCGdV5NWCw8Nh61NE=; b=M4q9r5YuY9zqXzB25za+JCzrfxAeP4ym8X/ygA/7FsiZI05MDB6im/Srdyn843QH0Y Xe7cEsgJZLeCWa4zU1yEckWznDAkIJteDoMSTN3o7y3kfxpFEqXzJ8Ht2Q1MVBZv6MWz TWo/mM/CiOgMptQGFfFZ/UBEdtEMRouze5t4rsaBAByPOAE21AYYVDaS5/Ysv++rBoPA zWSXdkcMSVBqbQPaWHXnTAf4I9RXisHH7fmx4DQQs1hoWMqmNlYv0iDMOlC76FKDpTsi Rl3Yvz73bwHHn4MdFJ2O0kA6GkNBGSABQQPt6rx2OG5N4Y7uea1MI4AXelMuvQkDUeN/ NcLQ== X-Gm-Message-State: AC+VfDwOI4Hc91vu7suoU+VeQQDekwoJk39WIQySHuwh4VwNHLokoJEo 37mGfuE3MgA3+DIq8twogBI8BtHszvlx41+tz2wcTA== X-Received: by 2002:a25:2843:0:b0:b9a:38b2:8067 with SMTP id o64-20020a252843000000b00b9a38b28067mr3442325ybo.12.1682689748091; Fri, 28 Apr 2023 06:49:08 -0700 (PDT) MIME-Version: 1.0 References: <20230424112313.3408363-1-glider@google.com> <6446ad55.170a0220.c82cd.cedc@mx.google.com> In-Reply-To: <6446ad55.170a0220.c82cd.cedc@mx.google.com> From: Alexander Potapenko Date: Fri, 28 Apr 2023 15:48:28 +0200 Message-ID: Subject: Re: [PATCH] string: use __builtin_memcpy() in strlcpy/strlcat To: Kees Cook Cc: linux-kernel@vger.kernel.org, linux-mm@kvack.org, akpm@linux-foundation.org, elver@google.com, dvyukov@google.com, kasan-dev@googlegroups.com, andy@kernel.org, ndesaulniers@google.com, nathan@kernel.org Content-Type: text/plain; charset="UTF-8" X-Spam-Status: No, score=-17.6 required=5.0 tests=BAYES_00,DKIMWL_WL_MED, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF, ENV_AND_HDR_SPF_MATCH,RCVD_IN_DNSWL_NONE,SPF_HELO_NONE,SPF_PASS, T_SCC_BODY_TEXT_LINE,USER_IN_DEF_DKIM_WL,USER_IN_DEF_SPF_WL autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org > > I *think* this isn't a problem for CONFIG_FORTIFY, since these will be > replaced and checked separately -- but it still seems strange that you > need to explicitly use __builtin_memcpy. > > Does this end up changing fortify coverage? Is fortify relevant here? Note that the whole file is compiled with __NO_FORTIFY.