From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wm0-f71.google.com (mail-wm0-f71.google.com [74.125.82.71]) by kanga.kvack.org (Postfix) with ESMTP id F2E816B0003 for ; Fri, 9 Mar 2018 09:02:12 -0500 (EST) Received: by mail-wm0-f71.google.com with SMTP id u83so1097379wmb.3 for ; Fri, 09 Mar 2018 06:02:12 -0800 (PST) Received: from mail-sor-f65.google.com (mail-sor-f65.google.com. [209.85.220.65]) by mx.google.com with SMTPS id n43sor544253wrb.85.2018.03.09.06.02.11 for (Google Transport Security); Fri, 09 Mar 2018 06:02:11 -0800 (PST) From: Andrey Konovalov Subject: [RFC PATCH 0/6] arm64: untag user pointers passed to the kernel Date: Fri, 9 Mar 2018 15:01:58 +0100 Message-Id: Sender: owner-linux-mm@kvack.org List-ID: To: Catalin Marinas , Will Deacon , Mark Rutland , Robin Murphy , Al Viro , Philippe Ombredanne , Greg Kroah-Hartman , Thomas Gleixner , Kate Stewart , Andrew Morton , "Kirill A . Shutemov" , Ingo Molnar , "Aneesh Kumar K . V" , Minchan Kim , Michal Hocko , Shaohua Li , Andrea Arcangeli , Anshuman Khandual , Mike Rapoport , Vlastimil Babka , Naoya Horiguchi , Shakeel Butt , Joonsoo Kim , Hugh Dickins , Mel Gorman , =?UTF-8?q?J=C3=A9r=C3=B4me=20Glisse?= , Mike Kravetz , Zi Yan , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-mm@kvack.org, Richard Henderson , Ivan Kokshaysky , Matt Turner , Vineet Gupta , Russell King , Mark Salter , Aurelien Jacquiot , Mikael Starvik , Jesper Nilsson , Tony Luck , Fenghua Yu , Geert Uytterhoeven , James Hogan , Michal Simek , Ralf Baechle , David Howells , Ley Foon Tan , Jonas Bonn , Stefan Kristiansson , Stafford Horne , "James E . J . Bottomley" , Helge Deller , Benjamin Herrenschmidt , Paul Mackerras , Michael Ellerman , Palmer Dabbelt , Albert Ou , Chen Liqin , Lennox Wu , Yoshinori Sato , Rich Felker , "David S . Miller" , Ingo Molnar , x86@kernel.org, Chris Zankel , Max Filippov , Arnd Bergmann , linux-alpha@vger.kernel.org, linux-snps-arc@lists.infradead.org, adi-buildroot-devel@lists.sourceforge.net, linux-c6x-dev@linux-c6x.org, linux-cris-kernel@axis.com, linux-ia64@vger.kernel.org, linux-m68k@lists.linux-m68k.org, linux-metag@vger.kernel.org, linux-mips@linux-mips.org, linux-am33-list@redhat.com, nios2-dev@lists.rocketboards.org, openrisc@lists.librecores.org, linux-parisc@vger.kernel.org, linuxppc-dev@lists.ozlabs.org, linux-riscv@lists.infradead.org, linux-sh@vger.kernel.org, sparclinux@vger.kernel.org, linux-xtensa@linux-xtensa.org, linux-arch@vger.kernel.org Cc: Dmitry Vyukov , Kostya Serebryany , Evgeniy Stepanov , Lee Smith , Ramana Radhakrishnan , Jacob Bramley , Ruben Ayrapetyan , Andrey Konovalov arm64 has a feature called Top Byte Ignore, which allows to embed pointer tags into the top byte of each pointer. Userspace programs (such as HWASan, a memory debugging tool [1]) might use this feature and pass tagged user pointers to the kernel through syscalls or other interfaces. This patch makes a few of the kernel interfaces accept tagged user pointers. The kernel is already able to handle user faults with tagged pointers and has the untagged_addr macro, which this patchset reuses. We're not trying to cover all possible ways the kernel accepts user pointers in one patchset, so this one should be considered as a start. It would be nice to learn about the interfaces that I missed though. Sending this as an RFC, as I'm not sure if this should be committed as is, and would like to receive some feedback. Thanks! [1] http://clang.llvm.org/docs/HardwareAssistedAddressSanitizerDesign.html Andrey Konovalov (6): arm64: add type casts to untagged_addr macro arm64: untag user addresses in copy_from_user and others mm, arm64: untag user addresses in memory syscalls mm, arm64: untag user addresses in mm/gup.c lib, arm64: untag addrs passed to strncpy_from_user and strnlen_user arch: add untagged_addr definition for other arches arch/alpha/include/asm/uaccess.h | 2 ++ arch/arc/include/asm/uaccess.h | 1 + arch/arm/include/asm/uaccess.h | 2 ++ arch/arm64/include/asm/uaccess.h | 9 +++++++-- arch/blackfin/include/asm/uaccess.h | 2 ++ arch/c6x/include/asm/uaccess.h | 2 ++ arch/cris/include/asm/uaccess.h | 2 ++ arch/frv/include/asm/uaccess.h | 2 ++ arch/ia64/include/asm/uaccess.h | 2 ++ arch/m32r/include/asm/uaccess.h | 2 ++ arch/m68k/include/asm/uaccess.h | 2 ++ arch/metag/include/asm/uaccess.h | 2 ++ arch/microblaze/include/asm/uaccess.h | 2 ++ arch/mips/include/asm/uaccess.h | 2 ++ arch/mn10300/include/asm/uaccess.h | 2 ++ arch/nios2/include/asm/uaccess.h | 2 ++ arch/openrisc/include/asm/uaccess.h | 2 ++ arch/parisc/include/asm/uaccess.h | 2 ++ arch/powerpc/include/asm/uaccess.h | 2 ++ arch/riscv/include/asm/uaccess.h | 2 ++ arch/score/include/asm/uaccess.h | 2 ++ arch/sh/include/asm/uaccess.h | 2 ++ arch/sparc/include/asm/uaccess.h | 2 ++ arch/tile/include/asm/uaccess.h | 2 ++ arch/x86/include/asm/uaccess.h | 2 ++ arch/xtensa/include/asm/uaccess.h | 2 ++ include/asm-generic/uaccess.h | 2 ++ lib/strncpy_from_user.c | 2 ++ lib/strnlen_user.c | 2 ++ mm/gup.c | 12 ++++++++++++ mm/madvise.c | 2 ++ mm/mempolicy.c | 6 ++++++ mm/mincore.c | 2 ++ mm/mlock.c | 5 +++++ mm/mmap.c | 9 +++++++++ mm/mprotect.c | 2 ++ mm/mremap.c | 2 ++ mm/msync.c | 3 +++ 38 files changed, 105 insertions(+), 2 deletions(-) -- 2.16.2.395.g2e18187dfd-goog