From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: from mail-pf1-f197.google.com (mail-pf1-f197.google.com [209.85.210.197]) by kanga.kvack.org (Postfix) with ESMTP id A822C6B1CB0 for ; Mon, 19 Nov 2018 16:54:55 -0500 (EST) Received: by mail-pf1-f197.google.com with SMTP id i22-v6so26684750pfj.1 for ; Mon, 19 Nov 2018 13:54:55 -0800 (PST) Received: from mga11.intel.com (mga11.intel.com. [192.55.52.93]) by mx.google.com with ESMTPS id s8si4586261plq.345.2018.11.19.13.54.54 for (version=TLS1_2 cipher=ECDHE-RSA-AES128-GCM-SHA256 bits=128/128); Mon, 19 Nov 2018 13:54:54 -0800 (PST) From: Yu-cheng Yu Subject: [RFC PATCH v6 01/11] x86/cet/ibt: Add Kconfig option for user-mode Indirect Branch Tracking Date: Mon, 19 Nov 2018 13:49:24 -0800 Message-Id: <20181119214934.6174-2-yu-cheng.yu@intel.com> In-Reply-To: <20181119214934.6174-1-yu-cheng.yu@intel.com> References: <20181119214934.6174-1-yu-cheng.yu@intel.com> Sender: owner-linux-mm@kvack.org List-ID: To: x86@kernel.org, "H. Peter Anvin" , Thomas Gleixner , Ingo Molnar , linux-kernel@vger.kernel.org, linux-doc@vger.kernel.org, linux-mm@kvack.org, linux-arch@vger.kernel.org, linux-api@vger.kernel.org, Arnd Bergmann , Andy Lutomirski , Balbir Singh , Cyrill Gorcunov , Dave Hansen , Eugene Syromiatnikov , Florian Weimer , "H.J. Lu" , Jann Horn , Jonathan Corbet , Kees Cook , Mike Kravetz , Nadav Amit , Oleg Nesterov , Pavel Machek , Peter Zijlstra , Randy Dunlap , "Ravi V. Shankar" , Vedvyas Shanbhogue Cc: Yu-cheng Yu The user-mode indirect branch tracking support is done mostly by GCC to insert ENDBR64/ENDBR32 instructions at branch targets. The kernel provides CPUID enumeration and feature setup. Signed-off-by: Yu-cheng Yu --- arch/x86/Kconfig | 16 ++++++++++++++++ arch/x86/Makefile | 7 +++++++ 2 files changed, 23 insertions(+) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 73dfb94cde71..b7f30ac89e27 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -1925,6 +1925,9 @@ config X86_INTEL_CET config ARCH_HAS_SHSTK def_bool n +config ARCH_HAS_AS_LIMIT + def_bool n + config ARCH_HAS_PROGRAM_PROPERTIES def_bool n @@ -1948,6 +1951,19 @@ config X86_INTEL_SHADOW_STACK_USER If unsure, say y. +config X86_INTEL_BRANCH_TRACKING_USER + prompt "Intel Indirect Branch Tracking for user-mode" + def_bool n + depends on CPU_SUP_INTEL && X86_64 + select X86_INTEL_CET + select ARCH_HAS_AS_LIMIT + select ARCH_HAS_PROGRAM_PROPERTIES + ---help--- + Indirect Branch Tracking provides hardware protection against return-/jmp- + oriented programming attacks. + + If unsure, say y + config EFI bool "EFI runtime service support" depends on ACPI diff --git a/arch/x86/Makefile b/arch/x86/Makefile index 0e4746814452..7e6c4aeb0d92 100644 --- a/arch/x86/Makefile +++ b/arch/x86/Makefile @@ -159,6 +159,13 @@ ifdef CONFIG_X86_INTEL_SHADOW_STACK_USER endif endif +# Check compiler ibt support +ifdef CONFIG_X86_INTEL_BRANCH_TRACKING_USER + ifeq ($(call cc-option-yn, -fcf-protection=branch), n) + $(error CONFIG_X86_INTEL_BRANCH_TRACKING_USER not supported by compiler) + endif +endif + # # If the function graph tracer is used with mcount instead of fentry, # '-maccumulate-outgoing-args' is needed to prevent a GCC bug -- 2.17.1