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 kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by smtp.lore.kernel.org (Postfix) with ESMTP id 03342C433F5 for ; Thu, 17 Feb 2022 07:52:48 +0000 (UTC) Received: by kanga.kvack.org (Postfix) id 65FE96B0074; Thu, 17 Feb 2022 02:52:48 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id 5E4C56B0075; Thu, 17 Feb 2022 02:52:48 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 45FF16B0078; Thu, 17 Feb 2022 02:52:48 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0046.hostedemail.com [216.40.44.46]) by kanga.kvack.org (Postfix) with ESMTP id 3852F6B0074 for ; Thu, 17 Feb 2022 02:52:48 -0500 (EST) Received: from smtpin23.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id DE63795188 for ; Thu, 17 Feb 2022 07:52:47 +0000 (UTC) X-FDA: 79151505174.23.7621BB8 Received: from mout.kundenserver.de (mout.kundenserver.de [212.227.126.130]) by imf10.hostedemail.com (Postfix) with ESMTP id 3E4E9C0002 for ; Thu, 17 Feb 2022 07:52:47 +0000 (UTC) Received: from mail-wr1-f54.google.com ([209.85.221.54]) by mrelayeu.kundenserver.de (mreue009 [213.165.67.97]) with ESMTPSA (Nemesis) id 1MhlCa-1ny3133FQW-00djcb for ; Thu, 17 Feb 2022 08:52:45 +0100 Received: by mail-wr1-f54.google.com with SMTP id d27so7441554wrc.6 for ; Wed, 16 Feb 2022 23:52:45 -0800 (PST) X-Gm-Message-State: AOAM533wt9ROvRNr7myGLnU9P/MGn0kxcLC5yQfEzpWSlklubc9h0zLa kdfURyGI7wBIii5t+oaoR4ovtG1W5JIW65sASiA= X-Google-Smtp-Source: ABdhPJwQLFNR2EKsG8wmZOAHPh9E9pyoICR3LxZT862dIjr2W4W3Sw6yF+ayzR5i5e/QGR8IN4+3KhdYVHoGFF4fNyc= X-Received: by 2002:adf:ea01:0:b0:1e4:b3e6:1f52 with SMTP id q1-20020adfea01000000b001e4b3e61f52mr1268592wrm.317.1645084364936; Wed, 16 Feb 2022 23:52:44 -0800 (PST) MIME-Version: 1.0 References: <20220216131332.1489939-1-arnd@kernel.org> <20220216131332.1489939-14-arnd@kernel.org> In-Reply-To: <20220216131332.1489939-14-arnd@kernel.org> From: Arnd Bergmann Date: Thu, 17 Feb 2022 08:52:29 +0100 X-Gmail-Original-Message-ID: Message-ID: Subject: Re: [PATCH v2 13/18] uaccess: generalize access_ok() To: Linus Torvalds , Christoph Hellwig , linux-arch , Linux-MM , Linux API , Arnd Bergmann , Linux Kernel Mailing List , Al Viro Cc: Russell King - ARM Linux , Will Deacon , Guo Ren , Brian Cain , Geert Uytterhoeven , Michal Simek , Thomas Bogendoerfer , Nick Hu , Greentime Hu , Dinh Nguyen , Stafford Horne , Helge Deller , Michael Ellerman , Peter Zijlstra , Ingo Molnar , Mark Rutland , Heiko Carstens , Rich Felker , David Miller , Richard Weinberger , "the arch/x86 maintainers" , Max Filippov , "Eric W . Biederman" , Andrew Morton , Ard Biesheuvel , alpha , "open list:SYNOPSYS ARC ARCHITECTURE" , linux-csky@vger.kernel.org, "open list:QUALCOMM HEXAGON..." , linux-ia64@vger.kernel.org, linux-m68k , "open list:BROADCOM NVRAM DRIVER" , Openrisc , Parisc List , linuxppc-dev , linux-riscv , linux-s390 , Linux-sh list , sparclinux , linux-um , "open list:TENSILICA XTENSA PORT (xtensa)" Content-Type: text/plain; charset="UTF-8" X-Provags-ID: V03:K1:gkmPcsakBf2WbPRgT2ZT1vheQS4Vsz9EkX/ifdUN1icyBYQZjpE ZkJu3+2y3vIX/2HDFmKhGj4amzyVKK6JwqjOkQheLsIIn+KFEyjo+jMdX4+VLaghwSAIw/U 4LdGwMILi9mcufNBLgKOB6ePX1a+HoMp4MRMooCvM3Kh5HrvFVpZ+pp/KBug7gDtiWQCAaD 6JZGfuaLBWJehjslUd2pQ== X-UI-Out-Filterresults: notjunk:1;V03:K0:kgGBiHliVMQ=:uOirjKEEobwYtZ3aOeFeg+ 1kYhcrQ20Xr360MlyWa1FHXt27ENZJqLBiRF0eis9YMdvWsigUMFWGkbaa1/nyfUf1tIUXLSP fXFVBkYZuQrFAp4qckzovct/fQf8NbgToGeqr9nXKDQvsaKNmlHe33AdyBsINP5cKxEh+vdWF FNOifa93uRrSDa1b3msYB7hBQAe00LBa6Nnd2tlrXxklnn5FzDj0zkXTyaVz0Vu87pM1stQwX CFe6GGy3nC30kXfYdQcpU48XUkp1GDiPINzklDRAqaebZxZGJSe0Tysrl3szpqL5o/yyjVTb1 12FrATwn29Cw0LOsbhENThZ8o+IHX1c09v1mI9gPIgssQ4EpTkE9p+j/lVwmuyIhWJJlQp42G hdwC+3AP2P4ZXoJqVE/IzAbmvQHf2htNIa0Fcaw7JxwtD/9AMD+rZayu78BGQZnmGMcxo4VKD Nq3Adg7eb6eKyKMcN6DlLuSiptA47myQEqUvzM5FRV9Zy9muWsMq7/2a05J7Z6WBjfTzZspB4 CQXQk9fefaAPRkk0IvxL3FZhvnHzm80s7SzQhwvbj5TCqs/FHjU2dMKiX1+GupUVDOZw6KHJU VZ4IRAIjE8BTx+V94izBqjoLjBhnI16m3LLnR5+sV3xni7Nsi8SBAj1i0yuGx5h0EJPt+0Ye+ ZWTTQ4DQoUL81cqk1cQqeCLgVET6tpGeomi23Itk4Cv8o5Kfw4Y1J0RcQITpdvMV0KnyvHyr8 U+gotOnHO9uGUu/A5Nkr8FFdbQFKk9g90SDVaSpW68Q+PeiVUeqbB+ViMEjT1hT91FnaG2n+E +9m/xaALwZLxM1nstCcOIecYWxRlnrAfhaHny5qaCkIeHLZTes= X-Rspam-User: X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 3E4E9C0002 X-Stat-Signature: qp6xaupff1s3ndns1bzetkuyphex6jfx Authentication-Results: imf10.hostedemail.com; dkim=none; dmarc=none; spf=none (imf10.hostedemail.com: domain of arnd@arndb.de has no SPF policy when checking 212.227.126.130) smtp.mailfrom=arnd@arndb.de X-HE-Tag: 1645084367-991129 X-Bogosity: Ham, tests=bogofilter, spamicity=0.000000, version=1.2.4 Sender: owner-linux-mm@kvack.org Precedence: bulk X-Loop: owner-majordomo@kvack.org List-ID: On Wed, Feb 16, 2022 at 2:13 PM Arnd Bergmann wrote: > + * limit and catch all possible overflows. > + * On architectures with separate user address space (m68k, s390, parisc, > + * sparc64) or those without an MMU, this should always return true. ... > +static inline int __access_ok(const void __user *ptr, unsigned long size) > +{ > + unsigned long limit = user_addr_max(); > + unsigned long addr = (unsigned long)ptr; > + > + if (IS_ENABLED(CONFIG_ALTERNATE_USER_ADDRESS_SPACE)) > + return true; I noticed that I'm missing the check for !CONFIG_MMU here, despite mentioning that in the comment above it. I've added it now. Arnd