Received: by 2002:a05:6a10:5bc5:0:0:0:0 with SMTP id os5csp764891pxb; Thu, 21 Oct 2021 09:04:17 -0700 (PDT) X-Google-Smtp-Source: ABdhPJyBMJO0L7mIUaconHWYwywBy5G3JjYcHhEfJDYAJEPfp7W6vagQvdOuAahOK/UVZff1hGP2 X-Received: by 2002:a17:902:8ec5:b0:13a:2789:cbb0 with SMTP id x5-20020a1709028ec500b0013a2789cbb0mr6062775plo.60.1634832257260; Thu, 21 Oct 2021 09:04:17 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1634832257; cv=none; d=google.com; s=arc-20160816; b=wPEh4F75coZRJvH+nzFSb0oY0qQgphgGhHO3ZmY8do13AE840oT/1oZhg1Tpl/GWYu DU7V6J6vfH5tOebGsUnSYUTyTfUzb6sKZE4pFX7EtbGijotgvqqv607zGRi3fuvz6aV6 WnlCxh187Qsp9CDlJQ+SO8Fro5pT5qmOVvoLVp1kvc4853bVkeLTCVkeuw/E6fiEu3F2 vKyJFwQxD3HWEy82GV4+2mE0YCOevGFy1Z7qUhRy3A7LJ6nFQV8xjh/iUnvGJuL9IpIk 0CDpiaRKm9G67gceLnFQncj1v5Gd40auwFyD/CeR/UkgtoGUuFOrqgS3pAXYiP2nJgOq OsTQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:in-reply-to:content-disposition:mime-version :references:message-id:subject:cc:to:from:date:dkim-signature; bh=/CORXWW/B4Qwj9AW68aZ4KNhoZHxannWXjlHOATBFC4=; b=rY4J79ow1tOdU2sN2nH0B1++wM1pYJ1dIMGidj10uDJkIfWaxXRv6kMsbPdFi4vC2u e7DsLB4ueUunoPlfjt1ICCbpjpQ2LII3TRQa03HpuliEr+zti4tl2dPmRwSzQ+XS6hIN 9YIVsuv2kNpZLL/ejX9QnbctUAPLYgOPZX/FXFKx6I86KlwZPTkqh7n9GKB9X/VmaKgu kunMKblD6mCiNPkBcQD3pa5pP/YT9zQhNjjSDacx7PoyFWpWtPD/8r5arQZHVLISm3HD xIJsHYD58a/G74Tw5hZ1gdqV5XvA577HOxL7VF+w37hyPn3gBTmiXr2ZLByh4jR9G51u 9LLQ== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@chromium.org header.s=google header.b=eGCVh7iu; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=chromium.org Return-Path: Received: from vger.kernel.org (vger.kernel.org. [23.128.96.18]) by mx.google.com with ESMTP id z10si9657688plg.42.2021.10.21.09.04.03; Thu, 21 Oct 2021 09:04:17 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18; Authentication-Results: mx.google.com; dkim=pass header.i=@chromium.org header.s=google header.b=eGCVh7iu; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=NONE dis=NONE) header.from=chromium.org Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S231773AbhJUQE6 (ORCPT + 99 others); Thu, 21 Oct 2021 12:04:58 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:33632 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230280AbhJUQE4 (ORCPT ); Thu, 21 Oct 2021 12:04:56 -0400 Received: from mail-pg1-x531.google.com (mail-pg1-x531.google.com [IPv6:2607:f8b0:4864:20::531]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5AE49C061764 for ; Thu, 21 Oct 2021 09:02:40 -0700 (PDT) Received: by mail-pg1-x531.google.com with SMTP id s136so736721pgs.4 for ; Thu, 21 Oct 2021 09:02:40 -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=/CORXWW/B4Qwj9AW68aZ4KNhoZHxannWXjlHOATBFC4=; b=eGCVh7iu96H0jRAA2kNpooj8KoN8V+qF5k/tMPYh9T8dj2P3h4M7h2OwVOz9gRAYd3 GQLgCcRbEv3HZ17b/U3sjewF7mffVFwlm6KExyl4WkMr7aoai3qMajnrEcAbSH+lS6O0 tyzGk2y/9jXCk6Sc9R45O3mFm+kM0OBVNLbIs= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=/CORXWW/B4Qwj9AW68aZ4KNhoZHxannWXjlHOATBFC4=; b=JstS1SbPmmHXBL+xtwO/MT3RMDVuYdqEWbjAFP2QplewL8H/jBFVIczrjjrG0+mIxP E3q7T6IajsFn271nLqFIXMEXzTa2Jj2BQlCXBTymY4i9b6/knx1ZbKhktPfocAn0Xng3 4bXFSH59rjlM+lXBIJNZvpoP415kh7l+G7Yrzwk4AGoeAdDppIhi5zDlX7yJhUBt/T9+ 5VitI0ZKXr6afbByeGquueAZGrq1u250O/s3WcuEkj0o8+Mh/+NZL14oxyfh436ulq4S TfAHhvbxVWlDfP1DjGkV2OPJyF4l5xwkVorFMXrITch/jQLRDGzOIL53CbuoY1242LFM ZJag== X-Gm-Message-State: AOAM531MrNAa/WUgxzpzlnEXwhLwYVObXL2RwlBufSWasocGI1OeC0LR 35goVd3iYz6hS5rsGBl/6iDsVkvOiS2NKw== X-Received: by 2002:a63:950f:: with SMTP id p15mr5103786pgd.265.1634832159821; Thu, 21 Oct 2021 09:02:39 -0700 (PDT) Received: from www.outflux.net (smtp.outflux.net. [198.145.64.163]) by smtp.gmail.com with ESMTPSA id a20sm6419924pfn.136.2021.10.21.09.02.39 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 21 Oct 2021 09:02:39 -0700 (PDT) Date: Thu, 21 Oct 2021 09:02:38 -0700 From: Kees Cook To: "Eric W. Biederman" Cc: linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, Linus Torvalds , Oleg Nesterov , Al Viro , Andy Lutomirski Subject: Re: [PATCH 01/20] exit/doublefault: Remove apparently bogus comment about rewind_stack_do_exit Message-ID: <202110210902.40730E333@keescook> References: <87y26nmwkb.fsf@disp2133> <20211020174406.17889-1-ebiederm@xmission.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20211020174406.17889-1-ebiederm@xmission.com> Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Wed, Oct 20, 2021 at 12:43:47PM -0500, Eric W. Biederman wrote: > I do not see panic calling rewind_stack_do_exit anywhere, nor can I > find anywhere in the history where doublefault_shim has called > rewind_stack_do_exit. So I don't think this comment was ever actually > correct. > > Cc: Andy Lutomirski > Fixes: 7d8d8cfdee9a ("x86/doublefault/32: Rewrite the x86_32 #DF handler and unify with 64-bit") > Signed-off-by: "Eric W. Biederman" Reviewed-by: Kees Cook -- Kees Cook