From patchwork Thu Feb 27 17:44:06 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Mark Brown X-Patchwork-Id: 11409057 Return-Path: Received: from mail.kernel.org (pdx-korg-mail-1.web.codeaurora.org [172.30.200.123]) by pdx-korg-patchwork-2.web.codeaurora.org (Postfix) with ESMTP id 9E9BF924 for ; Thu, 27 Feb 2020 17:44:24 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.kernel.org (Postfix) with ESMTP id 7EDD02469F for ; Thu, 27 Feb 2020 17:44:24 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=default; t=1582825464; bh=V5Q9am4GlYTcwRXiyWBdBVfK+aT5jUem9tE0iIoQq9I=; h=From:To:Cc:Subject:Date:List-ID:From; b=JDfoBoAZvvl3gKgrlJjKKyN2em32g8XWX/6br57Cv/HFG3Mg65ODU6RuqZxb0uxSa Pu93oPqKGR1ya4otPnmp4/Alvs4BYndwV2wf1PmmEW54h239JftdI+mM8f4Be/7+us gDEivBnl7pBeVnXlVCBsw6h5zwG6uHC9SMKbMSe4= Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1729903AbgB0RoV (ORCPT ); Thu, 27 Feb 2020 12:44:21 -0500 Received: from foss.arm.com ([217.140.110.172]:55414 "EHLO foss.arm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727053AbgB0RoV (ORCPT ); Thu, 27 Feb 2020 12:44:21 -0500 Received: from usa-sjc-imap-foss1.foss.arm.com (unknown [10.121.207.14]) by usa-sjc-mx-foss1.foss.arm.com (Postfix) with ESMTP id 819B91FB; Thu, 27 Feb 2020 09:44:20 -0800 (PST) Received: from localhost (unknown [10.37.6.21]) by usa-sjc-imap-foss1.foss.arm.com (Postfix) with ESMTPSA id EAF9C3F73B; Thu, 27 Feb 2020 09:44:19 -0800 (PST) From: Mark Brown To: Catalin Marinas , Will Deacon Cc: Alexander Viro , Paul Elliott , Peter Zijlstra , Yu-cheng Yu , Amit Kachhap , Vincenzo Frascino , Marc Zyngier , Eugene Syromiatnikov , Szabolcs Nagy , "H . J . Lu " , Andrew Jones , Kees Cook , Arnd Bergmann , Jann Horn , Richard Henderson , =?utf-8?q?Kristina_Mart?= =?utf-8?q?=C5=A1enko?= , Thomas Gleixner , Florian Weimer , Sudakshina Das , linux-arm-kernel@lists.infradead.org, linux-kernel@vger.kernel.org, linux-arch@vger.kernel.org, linux-fsdevel@vger.kernel.org, Mark Brown Subject: [PATCH v8 00/11] arm64: Branch Target Identification support Date: Thu, 27 Feb 2020 17:44:06 +0000 Message-Id: <20200227174417.23722-1-broonie@kernel.org> X-Mailer: git-send-email 2.20.1 MIME-Version: 1.0 Sender: linux-fsdevel-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-fsdevel@vger.kernel.org This patch series implements support for ARMv8.5-A Branch Target Identification (BTI), which is a control flow integrity protection feature introduced as part of the ARMv8.5-A extensions. Changes: v8: - Remove a redundant IS_ENABLED(CONFIG_ARM64_BTI) check. v7: - Rebase onto v5.6-rc3. - Move comment about keeping NT_GNU_PROPERTY_TYPE_0 internal into first patch. - Add an explicit check for system_supports_bti() when parsing BTI ELF property for improved robustness. v6: - Rebase onto v5.6-rc1. - Fix typos s/BYTPE/BTYPE/ in commit log for "arm64: BTI: Decode BYTPE bits when printing PSTATE". v5: - Changed a bunch of -EIO to -ENOEXEC in the ELF parsing code. - Move PSR_BTYPE defines to UAPI. - Use compat_user_mode() rather than open coding. - Fix a typo s/BYTPE/BTYPE/ in syscall.c v4: - Dropped patch fixing existing documentation as it has already been merged. - Convert WARN_ON() to WARN_ON_ONCE() in "ELF: Add ELF program property parsing support". - Added display of guarded pages to ptdump. - Updated for conversion of exception handling from assembler to C. Notes: * GCC 9 can compile backwards-compatible BTI-enabled code with -mbranch-protection=bti or -mbranch-protection=standard. * Binutils trunk supports the new ELF note, but this wasn't in a release the last time I posted this series. (The situation _might_ have changed in the meantime...) Creation of a BTI-enabled binary requires _everything_ linked in to be BTI-enabled. For now ld --force-bti can be used to override this, but some things may break until the required C library support is in place. There is no straightforward way to mark a .s file as BTI-enabled: scraping the output from gcc -S works as a quick hack for now. readelf -n can be used to examing the program properties in an ELF file. * Runtime mmap() and mprotect() can be used to enable BTI on a page-by-page basis using the new PROT_BTI, but the code in the affected pages still needs to be written or compiled to contain the appopriate BTI landing pads. Dave Martin (10): ELF: UAPI and Kconfig additions for ELF program properties ELF: Add ELF program property parsing support arm64: Basic Branch Target Identification support elf: Allow arch to tweak initial mmap prot flags arm64: elf: Enable BTI at exec based on ELF program properties arm64: BTI: Decode BYTPE bits when printing PSTATE arm64: unify native/compat instruction skipping arm64: traps: Shuffle code to eliminate forward declarations arm64: BTI: Reset BTYPE when skipping emulated instructions KVM: arm64: BTI: Reset BTYPE when skipping emulated instructions Mark Brown (1): arm64: mm: Display guarded pages in ptdump Documentation/arm64/cpu-feature-registers.rst | 2 + Documentation/arm64/elf_hwcaps.rst | 5 + arch/arm64/Kconfig | 25 +++ arch/arm64/include/asm/cpucaps.h | 3 +- arch/arm64/include/asm/cpufeature.h | 6 + arch/arm64/include/asm/elf.h | 50 ++++++ arch/arm64/include/asm/esr.h | 2 +- arch/arm64/include/asm/exception.h | 1 + arch/arm64/include/asm/hwcap.h | 1 + arch/arm64/include/asm/kvm_emulate.h | 6 +- arch/arm64/include/asm/mman.h | 37 +++++ arch/arm64/include/asm/pgtable-hwdef.h | 1 + arch/arm64/include/asm/pgtable.h | 2 +- arch/arm64/include/asm/ptrace.h | 1 + arch/arm64/include/asm/sysreg.h | 4 + arch/arm64/include/uapi/asm/hwcap.h | 1 + arch/arm64/include/uapi/asm/mman.h | 9 ++ arch/arm64/include/uapi/asm/ptrace.h | 9 ++ arch/arm64/kernel/cpufeature.c | 33 ++++ arch/arm64/kernel/cpuinfo.c | 1 + arch/arm64/kernel/entry-common.c | 11 ++ arch/arm64/kernel/process.c | 36 ++++- arch/arm64/kernel/ptrace.c | 2 +- arch/arm64/kernel/signal.c | 16 ++ arch/arm64/kernel/syscall.c | 18 +++ arch/arm64/kernel/traps.c | 127 +++++++-------- arch/arm64/mm/dump.c | 5 + fs/Kconfig.binfmt | 6 + fs/binfmt_elf.c | 145 +++++++++++++++++- fs/compat_binfmt_elf.c | 4 + include/linux/elf.h | 43 ++++++ include/linux/mm.h | 3 + include/uapi/linux/elf.h | 11 ++ 33 files changed, 551 insertions(+), 75 deletions(-) create mode 100644 arch/arm64/include/asm/mman.h create mode 100644 arch/arm64/include/uapi/asm/mman.h