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=-5.8 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE 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 897DBC49361 for ; Mon, 21 Jun 2021 02:18:29 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 713986117A for ; Mon, 21 Jun 2021 02:18:29 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230151AbhFUCUk (ORCPT ); Sun, 20 Jun 2021 22:20:40 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:35778 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230040AbhFUCUc (ORCPT ); Sun, 20 Jun 2021 22:20:32 -0400 Received: from mail-lj1-x236.google.com (mail-lj1-x236.google.com [IPv6:2a00:1450:4864:20::236]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 3E151C061760 for ; Sun, 20 Jun 2021 19:18:17 -0700 (PDT) Received: by mail-lj1-x236.google.com with SMTP id d13so22807013ljg.12 for ; Sun, 20 Jun 2021 19:18:17 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=linux-foundation.org; s=google; h=mime-version:references:in-reply-to:from:date:message-id:subject:to :cc; bh=dZejXSKJots0a5Xk5qseqeRM6JTbTp59SHNg6hTQH+o=; b=MAhMZqudZsSxZ/7jbtmYhk1RV1H9tJShm//WrMFiOV2ya/PC4lyBw53NovX2z0W3UQ lVW5QcVk8O7fSzPpRXICb0URT/gxy4ajlbBr3HqIyZlMxRX6b08rhnK5f1HRSHzKKYIK QB0Eqv+7FA7Oe20guNcwkG9wa52yJ/I7XOJfE= 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=dZejXSKJots0a5Xk5qseqeRM6JTbTp59SHNg6hTQH+o=; b=fyv+n83zmXlTbqWplp03H31TAMmgNAxFFotuc7gSgHDtrbRCX8T8E01f97+ZqhOZUc waJbtuqwe2Y/QKPLm6CxFyf+68U9lxnFhkFElTeiHeV5zUmIGmgvVb0g+ro49GSaktiM iAq6KE209z+i1czMJ76YouXDO/6K7+0Ogd9VDoAkGRz9FLNqvPuH+WlzWOB4oiBf9N/9 jg4WFGa5bq54gI2xYWZRWBem8PBSHB1DXBRxnSCz/7zWMBXdJIeSx2oHTok9rl+G/+12 OkshrMpRb9/TbbN7Ejt63rGbx9uPdVyi1n1bd4mr4i8G5QdXZm++VClKGTJc3rhYesiK BXXA== X-Gm-Message-State: AOAM5331KRKDWIUToN5zw2xVVTxY/MbmADnlATI56OLnI/m2RyjJ+sEB 7rtVkoKQQAYtpws9fg9l9so2Nunb/MWcuBYL X-Google-Smtp-Source: ABdhPJxFghOstZJRTq10oBlxUV4M5WssnWLOZZmRuWYTEmpa8WVEH1kvDjttJPnUWlblkwIh29CZdg== X-Received: by 2002:a2e:b24f:: with SMTP id n15mr19475029ljm.261.1624241895437; Sun, 20 Jun 2021 19:18:15 -0700 (PDT) Received: from mail-lf1-f48.google.com (mail-lf1-f48.google.com. [209.85.167.48]) by smtp.gmail.com with ESMTPSA id z2sm610575ljm.10.2021.06.20.19.18.13 for (version=TLS1_3 cipher=TLS_AES_128_GCM_SHA256 bits=128/128); Sun, 20 Jun 2021 19:18:14 -0700 (PDT) Received: by mail-lf1-f48.google.com with SMTP id f30so27540880lfj.1 for ; Sun, 20 Jun 2021 19:18:13 -0700 (PDT) X-Received: by 2002:a05:6512:557:: with SMTP id h23mr7348506lfl.253.1624241893502; Sun, 20 Jun 2021 19:18:13 -0700 (PDT) MIME-Version: 1.0 References: <87sg1p30a1.fsf@disp2133> <87pmwsytb3.fsf@disp2133> <87sg1lwhvm.fsf@disp2133> <6e47eff8-d0a4-8390-1222-e975bfbf3a65@gmail.com> <924ec53c-2fd9-2e1c-bbb1-3fda49809be4@gmail.com> <87eed4v2dc.fsf@disp2133> <5929e116-fa61-b211-342a-c706dcb834ca@gmail.com> <87fsxjorgs.fsf@disp2133> <87zgvqor7d.fsf_-_@disp2133> <87mtrpg47k.fsf@disp2133> <87pmwlek8d.fsf_-_@disp2133> <87k0mtek4n.fsf_-_@disp2133> <393c37de-5edf-effc-3d06-d7e63f34a317@gmail.com> In-Reply-To: <393c37de-5edf-effc-3d06-d7e63f34a317@gmail.com> From: Linus Torvalds Date: Sun, 20 Jun 2021 19:17:57 -0700 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH 1/2] alpha/ptrace: Record and handle the absence of switch_stack To: Michael Schmitz Cc: "Eric W. Biederman" , linux-arch , Jens Axboe , Oleg Nesterov , Al Viro , Linux Kernel Mailing List , Richard Henderson , Ivan Kokshaysky , Matt Turner , alpha , Geert Uytterhoeven , linux-m68k , Arnd Bergmann , Ley Foon Tan , Tejun Heo , Kees Cook Content-Type: text/plain; charset="UTF-8" Precedence: bulk List-ID: X-Mailing-List: linux-kernel@vger.kernel.org On Sun, Jun 20, 2021 at 7:01 PM Michael Schmitz wrote: > > instrumenting get_reg on m68k and using a similar patch to yours to warn > when unsaved registers are accessed on the switch stack, I get a hit > from getegid and getegid32, just by running a simple ptrace on ls. > > Going to wack those two moles now ... I don't see what's going on. Those system calls don't use the register state, afaik. What's the call chain, exactly? Linus