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 Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id 15A1BC433FE for ; Fri, 18 Nov 2022 08:58:28 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S241609AbiKRI6Z (ORCPT ); Fri, 18 Nov 2022 03:58:25 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:48476 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230523AbiKRI6W (ORCPT ); Fri, 18 Nov 2022 03:58:22 -0500 Received: from us-smtp-delivery-124.mimecast.com (us-smtp-delivery-124.mimecast.com [170.10.133.124]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id A41316EB7F for ; Fri, 18 Nov 2022 00:57:23 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=redhat.com; s=mimecast20190719; t=1668761842; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:content-transfer-encoding: in-reply-to:in-reply-to:references:references; bh=p0ERrz7JCn9BnDY0Ayxan7lnfD5vEWFwGFrA85kPodc=; b=OgUb7Rrvd0S/1tG9DsbgoEtyLBNYbCxqqbYFJDbu35hqQZr+wJtAgx+w6bHE4eJ5qICerB PrUVi5E4XJ3R+fwhh48R+uyH9MRTyR0deqnoNeQqWHjDMXZH/jSahOOlZYNILqGReO7bUD +MDfdnfgesbPwedipXYp9OSr/kKJZUc= Received: from mail-wr1-f69.google.com (mail-wr1-f69.google.com [209.85.221.69]) by relay.mimecast.com with ESMTP with STARTTLS (version=TLSv1.3, cipher=TLS_AES_128_GCM_SHA256) id us-mta-622-3H1xl5MJP7K-GWCrG3znDA-1; Fri, 18 Nov 2022 03:57:21 -0500 X-MC-Unique: 3H1xl5MJP7K-GWCrG3znDA-1 Received: by mail-wr1-f69.google.com with SMTP id w23-20020adf8bd7000000b002358f733307so1332931wra.17 for ; Fri, 18 Nov 2022 00:57:21 -0800 (PST) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=content-transfer-encoding:in-reply-to:organization:from :content-language:references:cc:to:subject:user-agent:mime-version :date:message-id:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=p0ERrz7JCn9BnDY0Ayxan7lnfD5vEWFwGFrA85kPodc=; b=n++0kjTpajodD7o80T6LiMc+I9gT76pOU4fETF/alGYCHzFR9oQJY71g52JzbURPuc zgxpPMpGIswEl44LzSNHcvxCngNEkOmwKdDPvgZ4ShDB7rjnoKAxSI4FUoEkpLCQ3Xwv 3VeqQ7BCCmg5OTO7l4EVBJWqlSPQgLLsouv5mvtQu56G2kb3GcK6vFP3+88nsRk/n6nT kt67cRD8bDhuJtUIenlMUpGSfFM+kVTRXIlendi7mPrsnOistMqRkOZG1YDOBBsTDzsg hWSew5PhZHIZhh//jj3loKvZ8r0Y0GmIMAsuZUELEcztFA2bE4raLObwpWpqEJuHDfzA t+Sw== X-Gm-Message-State: ANoB5plPObf9kIRDnPmcU6zqMNZaTJi1ojHbmGxFG9BzwlCsMsUJpf/k B910dcbysiS9X0nKeKwtyBayL5a4+rYWzUAKRQYnVSwD8wip5Yup7gULCkTtC/dfMZDsma1zZ92 e1Kzo8v+ESPctcTjIvr0v3vER X-Received: by 2002:adf:facd:0:b0:231:482f:ed6b with SMTP id a13-20020adffacd000000b00231482fed6bmr3694257wrs.253.1668761840126; Fri, 18 Nov 2022 00:57:20 -0800 (PST) X-Google-Smtp-Source: AA0mqf50oZR0yD/v8/9UR7ki7wIw/KZLKr9m6FVoEPYMGY5P+v3sgErCbw58kQiRgWrcKNl7n+7VHQ== X-Received: by 2002:adf:facd:0:b0:231:482f:ed6b with SMTP id a13-20020adffacd000000b00231482fed6bmr3694247wrs.253.1668761839750; Fri, 18 Nov 2022 00:57:19 -0800 (PST) Received: from ?IPV6:2003:cb:c704:f500:6512:fac3:2687:15ff? (p200300cbc704f5006512fac3268715ff.dip0.t-ipconnect.de. [2003:cb:c704:f500:6512:fac3:2687:15ff]) by smtp.gmail.com with ESMTPSA id 6-20020a05600c024600b003b50428cf66sm3709552wmj.33.2022.11.18.00.57.18 (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Fri, 18 Nov 2022 00:57:19 -0800 (PST) Message-ID: <16759fd4-3a8c-b52c-20c3-9a9129f26799@redhat.com> Date: Fri, 18 Nov 2022 09:57:18 +0100 MIME-Version: 1.0 User-Agent: Mozilla/5.0 (X11; Linux x86_64; rv:102.0) Gecko/20100101 Thunderbird/102.4.1 Subject: Re: [PATCH] exec: Remove FOLL_FORCE for stack setup To: Kees Cook , Eric Biederman Cc: Linus Torvalds , Alexander Viro , linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org References: <20221118003410.never.653-kees@kernel.org> Content-Language: en-US From: David Hildenbrand Organization: Red Hat In-Reply-To: <20221118003410.never.653-kees@kernel.org> Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 7bit Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On 18.11.22 01:34, Kees Cook wrote: > It does not appear that FOLL_FORCE should be needed for setting up the > stack pages. They are allocated using the nascent brpm->vma, which was > newly created with VM_STACK_FLAGS, which an arch can override, but they > all appear to include VM_WRITE | VM_MAYWRITE. Remove FOLL_FORCE. > > Cc: Eric Biederman > Cc: David Hildenbrand > Cc: Linus Torvalds > Cc: Alexander Viro > Cc: linux-fsdevel@vger.kernel.org > Cc: linux-mm@kvack.org > Link: https://lore.kernel.org/lkml/202211171439.CDE720EAD@keescook/ > Signed-off-by: Kees Cook Thanks for looking into this! Reviewed-by: David Hildenbrand -- Thanks, David / dhildenb