From mboxrd@z Thu Jan 1 00:00:00 1970 From: Andrey Konovalov Subject: [PATCH v5 00/10] arm64: untag user pointers passed to the kernel Date: Mon, 6 Aug 2018 18:40:35 +0200 Message-ID: Mime-Version: 1.0 Content-Transfer-Encoding: 8bit Return-path: Sender: linux-kernel-owner@vger.kernel.org To: Catalin Marinas , Will Deacon , Mark Rutland , Robin Murphy , Al Viro , Andrey Konovalov , Kees Cook , Kate Stewart , Greg Kroah-Hartman , Andrew Morton , Ingo Molnar , "Kirill A . Shutemov" , Shuah Khan , linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org, linux-mm@kvack.org, linux-arch@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Dmitry Vyukov , Kostya Serebryany , Evgeniy Stepanov , Lee Smith , Ramana Radhakrishnan , Jacob Bramley , Ruben Ayrapetyan , Chintan Pandya List-Id: linux-arch.vger.kernel.org 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. Thanks! [1] http://clang.llvm.org/docs/HardwareAssistedAddressSanitizerDesign.html Changes in v5: - Added 3 new patches that add untagging to places found with static analysis. - Rebased onto 44c929e1 (4.18-rc8). Changes in v4: - Added a selftest for checking that passing tagged pointers to the kernel succeeds. - Rebased onto 81e97f013 (4.18-rc1+). Changes in v3: - Rebased onto e5c51f30 (4.17-rc6+). - Added linux-arch@ to the list of recipients. Changes in v2: - Rebased onto 2d618bdf (4.17-rc3+). - Removed excessive untagging in gup.c. - Removed untagging pointers returned from __uaccess_mask_ptr. Changes in v1: - Rebased onto 4.17-rc1. Changes in RFC v2: - Added "#ifndef untagged_addr..." fallback in linux/uaccess.h instead of defining it for each arch individually. - Updated Documentation/arm64/tagged-pointers.txt. - Dropped "mm, arm64: untag user addresses in memory syscalls". - Rebased onto 3eb2ce82 (4.16-rc7). Andrey Konovalov (10): arm64: add type casts to untagged_addr macro uaccess: add untagged_addr definition for other arches arm64: untag user addresses in access_ok and __uaccess_mask_ptr mm, arm64: untag user addresses in mm/gup.c lib, arm64: untag addrs passed to strncpy_from_user and strnlen_user arm64: untag user address in __do_user_fault fs, arm64: untag user address in copy_mount_options usb, arm64: untag user addresses in devio arm64: update Documentation/arm64/tagged-pointers.txt selftests, arm64: add a selftest for passing tagged pointers to kernel Documentation/arm64/tagged-pointers.txt | 5 +++-- arch/arm64/include/asm/uaccess.h | 14 +++++++++----- arch/arm64/mm/fault.c | 2 +- drivers/usb/core/devio.c | 8 +++++--- fs/namespace.c | 2 +- include/linux/uaccess.h | 4 ++++ lib/strncpy_from_user.c | 2 ++ lib/strnlen_user.c | 2 ++ mm/gup.c | 4 ++++ tools/testing/selftests/arm64/.gitignore | 1 + tools/testing/selftests/arm64/Makefile | 11 +++++++++++ .../testing/selftests/arm64/run_tags_test.sh | 12 ++++++++++++ tools/testing/selftests/arm64/tags_test.c | 19 +++++++++++++++++++ 13 files changed, 74 insertions(+), 12 deletions(-) create mode 100644 tools/testing/selftests/arm64/.gitignore create mode 100644 tools/testing/selftests/arm64/Makefile create mode 100755 tools/testing/selftests/arm64/run_tags_test.sh create mode 100644 tools/testing/selftests/arm64/tags_test.c -- 2.18.0.597.ga71716f1ad-goog From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-wr1-f68.google.com ([209.85.221.68]:37328 "EHLO mail-wr1-f68.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S2387521AbeHFSus (ORCPT ); Mon, 6 Aug 2018 14:50:48 -0400 Received: by mail-wr1-f68.google.com with SMTP id u12-v6so12994493wrr.4 for ; Mon, 06 Aug 2018 09:40:53 -0700 (PDT) From: Andrey Konovalov Subject: [PATCH v5 00/10] arm64: untag user pointers passed to the kernel Date: Mon, 6 Aug 2018 18:40:35 +0200 Message-ID: MIME-Version: 1.0 Content-Transfer-Encoding: 8bit Sender: linux-arch-owner@vger.kernel.org List-ID: To: Catalin Marinas , Will Deacon , Mark Rutland , Robin Murphy , Al Viro , Andrey Konovalov , Kees Cook , Kate Stewart , Greg Kroah-Hartman , Andrew Morton , Ingo Molnar , "Kirill A . Shutemov" , Shuah Khan , linux-arm-kernel@lists.infradead.org, linux-doc@vger.kernel.org, linux-mm@kvack.org, linux-arch@vger.kernel.org, linux-kselftest@vger.kernel.org, linux-kernel@vger.kernel.org Cc: Dmitry Vyukov , Kostya Serebryany , Evgeniy Stepanov , Lee Smith , Ramana Radhakrishnan , Jacob Bramley , Ruben Ayrapetyan , Chintan Pandya Message-ID: <20180806164035.L80l_U9GCPheGkrPQQmROoJojZ2dtflaZ6MP3pGO0Ag@z> 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. Thanks! [1] http://clang.llvm.org/docs/HardwareAssistedAddressSanitizerDesign.html Changes in v5: - Added 3 new patches that add untagging to places found with static analysis. - Rebased onto 44c929e1 (4.18-rc8). Changes in v4: - Added a selftest for checking that passing tagged pointers to the kernel succeeds. - Rebased onto 81e97f013 (4.18-rc1+). Changes in v3: - Rebased onto e5c51f30 (4.17-rc6+). - Added linux-arch@ to the list of recipients. Changes in v2: - Rebased onto 2d618bdf (4.17-rc3+). - Removed excessive untagging in gup.c. - Removed untagging pointers returned from __uaccess_mask_ptr. Changes in v1: - Rebased onto 4.17-rc1. Changes in RFC v2: - Added "#ifndef untagged_addr..." fallback in linux/uaccess.h instead of defining it for each arch individually. - Updated Documentation/arm64/tagged-pointers.txt. - Dropped "mm, arm64: untag user addresses in memory syscalls". - Rebased onto 3eb2ce82 (4.16-rc7). Andrey Konovalov (10): arm64: add type casts to untagged_addr macro uaccess: add untagged_addr definition for other arches arm64: untag user addresses in access_ok and __uaccess_mask_ptr mm, arm64: untag user addresses in mm/gup.c lib, arm64: untag addrs passed to strncpy_from_user and strnlen_user arm64: untag user address in __do_user_fault fs, arm64: untag user address in copy_mount_options usb, arm64: untag user addresses in devio arm64: update Documentation/arm64/tagged-pointers.txt selftests, arm64: add a selftest for passing tagged pointers to kernel Documentation/arm64/tagged-pointers.txt | 5 +++-- arch/arm64/include/asm/uaccess.h | 14 +++++++++----- arch/arm64/mm/fault.c | 2 +- drivers/usb/core/devio.c | 8 +++++--- fs/namespace.c | 2 +- include/linux/uaccess.h | 4 ++++ lib/strncpy_from_user.c | 2 ++ lib/strnlen_user.c | 2 ++ mm/gup.c | 4 ++++ tools/testing/selftests/arm64/.gitignore | 1 + tools/testing/selftests/arm64/Makefile | 11 +++++++++++ .../testing/selftests/arm64/run_tags_test.sh | 12 ++++++++++++ tools/testing/selftests/arm64/tags_test.c | 19 +++++++++++++++++++ 13 files changed, 74 insertions(+), 12 deletions(-) create mode 100644 tools/testing/selftests/arm64/.gitignore create mode 100644 tools/testing/selftests/arm64/Makefile create mode 100755 tools/testing/selftests/arm64/run_tags_test.sh create mode 100644 tools/testing/selftests/arm64/tags_test.c -- 2.18.0.597.ga71716f1ad-goog