From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kees Cook Subject: Re: [PATCH mm-unstable v1 20/20] mm: rename FOLL_FORCE to FOLL_PTRACE Date: Thu, 17 Nov 2022 14:58:19 -0800 Message-ID: <202211171439.CDE720EAD@keescook> References: <20221116102659.70287-1-david@redhat.com> <20221116102659.70287-21-david@redhat.com> Mime-Version: 1.0 Return-path: DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=gB4fu8WxG++brcac1xEx09Jo8IsSv6jaRuNq5hahL+I=; b=Fy4BdUGW9a1WNEtqYFLG188KBaVxCW7dlYHJCJYByhqbYzWtrREex26XefPtc0cld6 YCRtECSkUML5k6sMmax4MrQy/8YHDQGVY6nBvl6IgyA0kq1FCwf8z9yqhcxsos46Zhwv H1rDgpoCNHoreRPMRNhXYMHZ9u7/T1h/SC+nQ= Content-Disposition: inline In-Reply-To: List-ID: Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Linus Torvalds Cc: David Hildenbrand , linux-kernel@vger.kernel.org, x86@kernel.org, linux-alpha@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-ia64@vger.kernel.org, linux-mips@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, sparclinux@vger.kernel.org, linux-um@lists.infradead.org, etnaviv@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-samsung-soc@vger.kernel.org, linux-rdma@vger.kernel.org, linux-media@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-perf-users@vger.kernel.org, linux-security-module@vger.kernel.org, linux-kselftest@vger.kernel.org, Andrew Morton , Jason Gunthorpe , John Hubbard , Peter Xu , Greg Kroah-Hartman On Wed, Nov 16, 2022 at 10:16:34AM -0800, Linus Torvalds wrote: > There _are_ also small random cases too, like get_cmdline(). Maybe > that counts as ptrace, but the execve() case most definitely does not. Oh, er, why does get_arg_page() even need FOLL_FORCE? This is writing the new stack contents to the nascent brpm->vma, which was newly allocated with VM_STACK_FLAGS, which an arch can override, but they all appear to include VM_WRITE | VM_MAYWRITE. -- Kees Cook From mboxrd@z Thu Jan 1 00:00:00 1970 From: Kees Cook Date: Thu, 17 Nov 2022 22:58:19 +0000 Subject: Re: [PATCH mm-unstable v1 20/20] mm: rename FOLL_FORCE to FOLL_PTRACE Message-Id: <202211171439.CDE720EAD@keescook> List-Id: References: <20221116102659.70287-1-david@redhat.com> <20221116102659.70287-21-david@redhat.com> In-Reply-To: MIME-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Content-Transfer-Encoding: 7bit To: Linus Torvalds Cc: David Hildenbrand , linux-kernel@vger.kernel.org, x86@kernel.org, linux-alpha@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-ia64@vger.kernel.org, linux-mips@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, sparclinux@vger.kernel.org, linux-um@lists.infradead.org, etnaviv@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-samsung-soc@vger.kernel.org, linux-rdma@vger.kernel.org, linux-media@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-perf-users@vger.kernel.org, linux-security-module@vger.kernel.org, linux-kselftest@vger.kernel.org, Andrew Morton , Jason Gunthorpe , John Hubbard , Peter Xu , Greg Kroah-Hartman , Andrea Arcangeli , Hugh Dickins , Nadav Amit , Vlastimil Babka , Matthew Wilcox , Mike Kravetz , Muchun Song , Shuah Khan , Lucas Stach , David Airlie , Oded Gabbay , Arnd Bergmann , Christoph Hellwig , Alex Williamson , Oleg Nesterov , Richard Henderson , Ivan Kokshaysky , Matt Turner , Catalin Marinas , Will Deacon , Thomas Bogendoerfer , Michael Ellerman , Nicholas Piggin , Christophe Leroy , "David S. Miller" , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , "H. Peter Anvin" , Richard Weinberger , Anton Ivanov , Johannes Berg , Eric Biederman , Alexander Viro , Peter Zijlstra , Arnaldo Carvalho de Melo , Mark Rutland , Alexander Shishkin , Jiri Olsa , Namhyung Kim , Kentaro Takeda , Tetsuo Handa , Paul Moore , James Morris , "Serge E. Hallyn" On Wed, Nov 16, 2022 at 10:16:34AM -0800, Linus Torvalds wrote: > There _are_ also small random cases too, like get_cmdline(). Maybe > that counts as ptrace, but the execve() case most definitely does not. Oh, er, why does get_arg_page() even need FOLL_FORCE? This is writing the new stack contents to the nascent brpm->vma, which was newly allocated with VM_STACK_FLAGS, which an arch can override, but they all appear to include VM_WRITE | VM_MAYWRITE. -- Kees Cook 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 A9D62C43219 for ; Thu, 17 Nov 2022 22:58:27 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S235006AbiKQW6Z (ORCPT ); Thu, 17 Nov 2022 17:58:25 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54580 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S235197AbiKQW6X (ORCPT ); Thu, 17 Nov 2022 17:58:23 -0500 Received: from mail-pl1-x62d.google.com (mail-pl1-x62d.google.com [IPv6:2607:f8b0:4864:20::62d]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id B68D115829 for ; Thu, 17 Nov 2022 14:58:21 -0800 (PST) Received: by mail-pl1-x62d.google.com with SMTP id b21so2983770plc.9 for ; Thu, 17 Nov 2022 14:58:21 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=gB4fu8WxG++brcac1xEx09Jo8IsSv6jaRuNq5hahL+I=; b=Fy4BdUGW9a1WNEtqYFLG188KBaVxCW7dlYHJCJYByhqbYzWtrREex26XefPtc0cld6 YCRtECSkUML5k6sMmax4MrQy/8YHDQGVY6nBvl6IgyA0kq1FCwf8z9yqhcxsos46Zhwv H1rDgpoCNHoreRPMRNhXYMHZ9u7/T1h/SC+nQ= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=gB4fu8WxG++brcac1xEx09Jo8IsSv6jaRuNq5hahL+I=; b=kbfiClImaChoN1j/xrVu9gVsrQt1hH6ngQxJ2ysK4iQoiFuWCEnxp9eL1ZWfTcX25O AX6kyxIqWICakvjcqKlWg2xJQ8uvicy+ZyOD25Qf6ji2NgvxCyUZhJLJxs/FwcqUsKvp 8qdSgIURa1yR9+NGR68xQQ2x7GmXxEtN+qiN1vo8rDE08ztj9c+C/Af6Se7V68Ci9OsR GwkOZVktdYaf1OCmh8hl2o/Tyo6e0iduGMy1P/vzSuoDLt9pPGgnmbJsv7O6SrklpMM3 L17tuvAytBoQ95omcEXjjhb4sbGZT0r9GbMnHpxp+I2fpeaczXNlVBIDLDeB6hexndY9 rmrg== X-Gm-Message-State: ANoB5pn93+ivVT16W3WJlK7A0sMa6VJwhUQgEdwINtd7eFyt73Hct+Zf R6OxPYltkUBrMDYLcj65G+T6hA== X-Google-Smtp-Source: AA0mqf5a5ur58uPnDpwIjYXEwn4PnQ44wkjJwk4UbGX/PChCoGId0YIreHCZd3TM/oH8mIHpTiFUgA== X-Received: by 2002:a17:90a:2b46:b0:213:aa5f:a026 with SMTP id y6-20020a17090a2b4600b00213aa5fa026mr4652677pjc.243.1668725901245; Thu, 17 Nov 2022 14:58:21 -0800 (PST) Received: from www.outflux.net (198-0-35-241-static.hfc.comcastbusiness.net. [198.0.35.241]) by smtp.gmail.com with ESMTPSA id a11-20020a170902710b00b00186bc66d2cbsm1970473pll.73.2022.11.17.14.58.20 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 17 Nov 2022 14:58:20 -0800 (PST) Date: Thu, 17 Nov 2022 14:58:19 -0800 From: Kees Cook To: Linus Torvalds Cc: David Hildenbrand , linux-kernel@vger.kernel.org, x86@kernel.org, linux-alpha@vger.kernel.org, linux-arm-kernel@lists.infradead.org, linux-ia64@vger.kernel.org, linux-mips@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, sparclinux@vger.kernel.org, linux-um@lists.infradead.org, etnaviv@lists.freedesktop.org, dri-devel@lists.freedesktop.org, linux-samsung-soc@vger.kernel.org, linux-rdma@vger.kernel.org, linux-media@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-mm@kvack.org, linux-perf-users@vger.kernel.org, linux-security-module@vger.kernel.org, linux-kselftest@vger.kernel.org, Andrew Morton , Jason Gunthorpe , John Hubbard , Peter Xu , Greg Kroah-Hartman , Andrea Arcangeli , Hugh Dickins , Nadav Amit , Vlastimil Babka , Matthew Wilcox , Mike Kravetz , Muchun Song , Shuah Khan , Lucas Stach , David Airlie , Oded Gabbay , Arnd Bergmann , Christoph Hellwig , Alex Williamson , Oleg Nesterov , Richard Henderson , Ivan Kokshaysky , Matt Turner , Catalin Marinas , Will Deacon , Thomas Bogendoerfer , Michael Ellerman , Nicholas Piggin , Christophe Leroy , "David S. Miller" , Thomas Gleixner , Ingo Molnar , Borislav Petkov , Dave Hansen , "H. Peter Anvin" , Richard Weinberger , Anton Ivanov , Johannes Berg , Eric Biederman , Alexander Viro , Peter Zijlstra , Arnaldo Carvalho de Melo , Mark Rutland , Alexander Shishkin , Jiri Olsa , Namhyung Kim , Kentaro Takeda , Tetsuo Handa , Paul Moore , James Morris , "Serge E. Hallyn" Subject: Re: [PATCH mm-unstable v1 20/20] mm: rename FOLL_FORCE to FOLL_PTRACE Message-ID: <202211171439.CDE720EAD@keescook> References: <20221116102659.70287-1-david@redhat.com> <20221116102659.70287-21-david@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: Precedence: bulk List-ID: X-Mailing-List: linux-kselftest@vger.kernel.org On Wed, Nov 16, 2022 at 10:16:34AM -0800, Linus Torvalds wrote: > There _are_ also small random cases too, like get_cmdline(). Maybe > that counts as ptrace, but the execve() case most definitely does not. Oh, er, why does get_arg_page() even need FOLL_FORCE? This is writing the new stack contents to the nascent brpm->vma, which was newly allocated with VM_STACK_FLAGS, which an arch can override, but they all appear to include VM_WRITE | VM_MAYWRITE. -- Kees Cook 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 lists.ozlabs.org (lists.ozlabs.org [112.213.38.117]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 922E7C433FE for ; Fri, 18 Nov 2022 03:26:29 +0000 (UTC) Received: from boromir.ozlabs.org (localhost [IPv6:::1]) by lists.ozlabs.org (Postfix) with ESMTP id 4ND2J352JVz3cZp for ; Fri, 18 Nov 2022 14:26:27 +1100 (AEDT) Authentication-Results: lists.ozlabs.org; dkim=fail reason="signature verification failed" (1024-bit key; unprotected) header.d=chromium.org header.i=@chromium.org header.a=rsa-sha256 header.s=google header.b=Fy4BdUGW; dkim-atps=neutral Authentication-Results: lists.ozlabs.org; spf=pass (sender SPF authorized) smtp.mailfrom=chromium.org (client-ip=2607:f8b0:4864:20::434; helo=mail-pf1-x434.google.com; envelope-from=keescook@chromium.org; receiver=) Authentication-Results: lists.ozlabs.org; dkim=pass (1024-bit key; unprotected) header.d=chromium.org header.i=@chromium.org header.a=rsa-sha256 header.s=google header.b=Fy4BdUGW; dkim-atps=neutral Received: from mail-pf1-x434.google.com (mail-pf1-x434.google.com [IPv6:2607:f8b0:4864:20::434]) (using TLSv1.3 with cipher TLS_AES_256_GCM_SHA384 (256/256 bits) key-exchange X25519 server-signature RSA-PSS (2048 bits) server-digest SHA256) (No client certificate requested) by lists.ozlabs.org (Postfix) with ESMTPS id 4NCwLp3Q6vz3bbb for ; Fri, 18 Nov 2022 09:58:24 +1100 (AEDT) Received: by mail-pf1-x434.google.com with SMTP id g62so3189263pfb.10 for ; Thu, 17 Nov 2022 14:58:24 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=gB4fu8WxG++brcac1xEx09Jo8IsSv6jaRuNq5hahL+I=; b=Fy4BdUGW9a1WNEtqYFLG188KBaVxCW7dlYHJCJYByhqbYzWtrREex26XefPtc0cld6 YCRtECSkUML5k6sMmax4MrQy/8YHDQGVY6nBvl6IgyA0kq1FCwf8z9yqhcxsos46Zhwv H1rDgpoCNHoreRPMRNhXYMHZ9u7/T1h/SC+nQ= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=gB4fu8WxG++brcac1xEx09Jo8IsSv6jaRuNq5hahL+I=; b=27VTN2DJKVTIEzyxe/JkFUksgz8cit9LDQFuXnt42xqYyGxgpEVJH8NNMGUhXi3ORx Z9O1ZL2xRGsite+4beqaNM7/Azj5RoK3Yt6j5NfxMD9GF+AamrEFqPXJktm7XuJBwWoe 5RQiOjFBYoYGySDXHx+NjyZiKgOfWWzgW68MFVaABTZpvO8oamNg6izo9J5fOIGSI/y0 jrl6ptnt/mSGuE7LzXrkKBU5yqW3wEUlqITwFk7FRCOzfXAU6PBBgtTxEmTrZ0kZspM0 HvOGdX4srP65LYX0+d2EWN/62H4YSkC76z41MWFTxOvyLjs0kXRk0rpE5zFM3BrvMTQZ 4XGA== X-Gm-Message-State: ANoB5pkzHb37360WKDw5ZdgklnbGw4tW2czMAypBm50afZFKXh1qJDJu fiFsHsEYAgf0Lka6699NtAwhgA== X-Google-Smtp-Source: AA0mqf6WctuXnFpA5+6mUDbrkWFd9cOPvCXdH+vpFiVVPZ82O749B2W9Fe6xlTKz0BNICgCat8tmyw== X-Received: by 2002:aa7:80d0:0:b0:565:c4e2:2634 with SMTP id a16-20020aa780d0000000b00565c4e22634mr5143922pfn.0.1668725901160; Thu, 17 Nov 2022 14:58:21 -0800 (PST) Received: from www.outflux.net (198-0-35-241-static.hfc.comcastbusiness.net. [198.0.35.241]) by smtp.gmail.com with ESMTPSA id u139-20020a627991000000b00561cf757749sm1677934pfc.183.2022.11.17.14.58.20 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 17 Nov 2022 14:58:20 -0800 (PST) Date: Thu, 17 Nov 2022 14:58:19 -0800 From: Kees Cook To: Linus Torvalds Subject: Re: [PATCH mm-unstable v1 20/20] mm: rename FOLL_FORCE to FOLL_PTRACE Message-ID: <202211171439.CDE720EAD@keescook> References: <20221116102659.70287-1-david@redhat.com> <20221116102659.70287-21-david@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-Mailman-Approved-At: Fri, 18 Nov 2022 14:25:36 +1100 X-BeenThere: linuxppc-dev@lists.ozlabs.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Linux on PowerPC Developers Mail List List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , linux-ia64@vger.kernel.org, David Hildenbrand , Peter Zijlstra , Catalin Marinas , Tetsuo Handa , Dave Hansen , dri-devel@lists.freedesktop.org, linux-mips@vger.kernel.org, linux-mm@kvack.org, Will Deacon , Nadav Amit , linux-kselftest@vger.kernel.org, "H. Peter Anvin" , sparclinux@vger.kernel.org, Shuah Khan , Anton Ivanov , Andrea Arcangeli , linux-samsung-soc@vger.kernel.org, Paul Moore , linux-rdma@vger.kernel.org, David Airlie , x86@kernel.org, Hugh Dickins , James Morris , Matthew Wilcox , Christoph Hellwig , Jason Gunthorpe , Ingo Molnar , Vla stimil Babka , Matt Turner , Kentaro Takeda , linux-media@vger.kernel.org, Arnd Bergmann , John Hubbard , linux-um@lists.infradead.org, etnaviv@lists.freedesktop.org, Nicholas Piggin , Richard Weinberger , Alex Williamson , Ivan Kokshaysky , Peter Xu , Muchun Song , Namhyung Kim , Thomas Gleixner , Richard Henderson , Arnaldo Carvalho de Melo , Oleg Nesterov , linux-arm-kernel@lists.infradead.org, "Serge E. Hallyn" , Thomas Bogendoerfer , Greg Kroah-Hartman , Oded Gabbay , linux-kernel@vger.kernel.org, Alexander Shishkin , Alex ander Viro , linux-perf-users@vger.kernel.org, Johannes Berg , linux-security-module@vger.kernel.org, Eric Biederman , Jiri Olsa , linux-alpha@vger.kernel.org, linux-fsdevel@vger.kernel.org, Borislav Petkov , Andrew Morton , Lucas Stach , linuxppc-dev@lists.ozlabs.org, "David S. Miller" , Mike Kravetz Errors-To: linuxppc-dev-bounces+linuxppc-dev=archiver.kernel.org@lists.ozlabs.org Sender: "Linuxppc-dev" On Wed, Nov 16, 2022 at 10:16:34AM -0800, Linus Torvalds wrote: > There _are_ also small random cases too, like get_cmdline(). Maybe > that counts as ptrace, but the execve() case most definitely does not. Oh, er, why does get_arg_page() even need FOLL_FORCE? This is writing the new stack contents to the nascent brpm->vma, which was newly allocated with VM_STACK_FLAGS, which an arch can override, but they all appear to include VM_WRITE | VM_MAYWRITE. -- Kees Cook 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 gabe.freedesktop.org (gabe.freedesktop.org [131.252.210.177]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by smtp.lore.kernel.org (Postfix) with ESMTPS id 948EBC433FE for ; Thu, 17 Nov 2022 22:58:28 +0000 (UTC) Received: from gabe.freedesktop.org (localhost [127.0.0.1]) by gabe.freedesktop.org (Postfix) with ESMTP id 3083010E6BE; Thu, 17 Nov 2022 22:58:26 +0000 (UTC) Received: from mail-pg1-x52b.google.com (mail-pg1-x52b.google.com [IPv6:2607:f8b0:4864:20::52b]) by gabe.freedesktop.org (Postfix) with ESMTPS id 9394210E6BC for ; Thu, 17 Nov 2022 22:58:21 +0000 (UTC) Received: by mail-pg1-x52b.google.com with SMTP id 130so3443443pgc.5 for ; Thu, 17 Nov 2022 14:58:21 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:from:to:cc:subject:date:message-id:reply-to; bh=gB4fu8WxG++brcac1xEx09Jo8IsSv6jaRuNq5hahL+I=; b=Fy4BdUGW9a1WNEtqYFLG188KBaVxCW7dlYHJCJYByhqbYzWtrREex26XefPtc0cld6 YCRtECSkUML5k6sMmax4MrQy/8YHDQGVY6nBvl6IgyA0kq1FCwf8z9yqhcxsos46Zhwv H1rDgpoCNHoreRPMRNhXYMHZ9u7/T1h/SC+nQ= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20210112; h=in-reply-to:content-disposition:mime-version:references:message-id :subject:cc:to:from:date:x-gm-message-state:from:to:cc:subject:date :message-id:reply-to; bh=gB4fu8WxG++brcac1xEx09Jo8IsSv6jaRuNq5hahL+I=; b=G9tlcwVK4Vuq5+D7ExCGYT+jZ5hvynHTsB4L8J3Q5AmtmDMFnPjXGUJcgxVOuSUj1A Kel2U2JzN1OdNitfct+47j1aLMGf96ZLkj9CYsbkJhnVsK5dovCasDdJWEybuiC3iPPx P73hhJyrBXpHAAl/N7vEt45uj5wXt537ygh2VCTnbQZGtuIkPF+AeuU+9VD1XDCbhQ8k rrik8bj3/xZxDFDYidV+mJGsHd2pDaa1zxlRFCnnfgbFh94p8vHj7Vm37cHKNuZLB5Ua OuCZIFeDUG31nvzswtvbp9QXUryNIrxHYK7fipXPltYMnqkEe+U66gu3E2AtcHiJhPXI A9YA== X-Gm-Message-State: ANoB5plig4/kvdScyKsynYEvpoGP2yWj3PS6/MnYfdTRS7A/a5P4FCLJ DJCWG7qJeQxSnOCJ1tOa4ZEc8Q== X-Google-Smtp-Source: AA0mqf6WctuXnFpA5+6mUDbrkWFd9cOPvCXdH+vpFiVVPZ82O749B2W9Fe6xlTKz0BNICgCat8tmyw== X-Received: by 2002:aa7:80d0:0:b0:565:c4e2:2634 with SMTP id a16-20020aa780d0000000b00565c4e22634mr5143922pfn.0.1668725901160; Thu, 17 Nov 2022 14:58:21 -0800 (PST) Received: from www.outflux.net (198-0-35-241-static.hfc.comcastbusiness.net. [198.0.35.241]) by smtp.gmail.com with ESMTPSA id u139-20020a627991000000b00561cf757749sm1677934pfc.183.2022.11.17.14.58.20 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Thu, 17 Nov 2022 14:58:20 -0800 (PST) Date: Thu, 17 Nov 2022 14:58:19 -0800 From: Kees Cook To: Linus Torvalds Subject: Re: [PATCH mm-unstable v1 20/20] mm: rename FOLL_FORCE to FOLL_PTRACE Message-ID: <202211171439.CDE720EAD@keescook> References: <20221116102659.70287-1-david@redhat.com> <20221116102659.70287-21-david@redhat.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: X-BeenThere: dri-devel@lists.freedesktop.org X-Mailman-Version: 2.1.29 Precedence: list List-Id: Direct Rendering Infrastructure - Development List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , Cc: Mark Rutland , linux-ia64@vger.kernel.org, David Hildenbrand , Peter Zijlstra , Catalin Marinas , Tetsuo Handa , Dave Hansen , dri-devel@lists.freedesktop.org, linux-mips@vger.kernel.org, linux-mm@kvack.org, Will Deacon , Nadav Amit , Michael Ellerman , linux-kselftest@vger.kernel.org, "H. Peter Anvin" , sparclinux@vger.kernel.org, Shuah Khan , Anton Ivanov , Andrea Arcangeli , linux-samsung-soc@vger.kernel.org, Paul Moore , linux-rdma@vger.kernel.org, x86@kernel.org, Hugh Dickins , James Morris , Matthew Wilcox , Christoph Hellwig , Jason Gunthorpe , Ingo Molnar , Vlastimil Babka , Matt Turner , Kentaro Takeda , linux-media@vger.kernel.org, Arnd Bergmann , John Hubbard , linux-um@lists.infradead.org, etnaviv@lists.freedesktop.org, Nicholas Piggin , Richard Weinberger , Alex Williamson , Ivan Kokshaysky , Peter Xu , Muchun Song , Namhyung Kim , Thomas Gleixner , Richard Henderson , Arnaldo Carvalho de Melo , Oleg Nesterov , linux-arm-kernel@lists.infradead.org, "Serge E. Hallyn" , Thomas Bogendoerfer , Christophe Leroy , Greg Kroah-Hartman , Oded Gabbay , linux-kernel@vger.kernel.org, Alexander Shishkin , Alexander Viro , linux-perf-users@vger.kernel.org, Johannes Berg , linux-security-module@vger.kernel.org, Eric Biederman , Jiri Olsa , linux-alpha@vger.kernel.org, linux-fsdevel@vger.kernel.org, Borislav Petkov , Andrew Morton , linuxppc-dev@lists.ozlabs.org, "David S. Miller" , Mike Kravetz Errors-To: dri-devel-bounces@lists.freedesktop.org Sender: "dri-devel" On Wed, Nov 16, 2022 at 10:16:34AM -0800, Linus Torvalds wrote: > There _are_ also small random cases too, like get_cmdline(). Maybe > that counts as ptrace, but the execve() case most definitely does not. Oh, er, why does get_arg_page() even need FOLL_FORCE? This is writing the new stack contents to the nascent brpm->vma, which was newly allocated with VM_STACK_FLAGS, which an arch can override, but they all appear to include VM_WRITE | VM_MAYWRITE. -- Kees Cook