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 X-Spam-Level: X-Spam-Status: No, score=-16.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT autolearn=ham autolearn_force=no version=3.4.0 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by smtp.lore.kernel.org (Postfix) with ESMTP id 114EAC433E6 for ; Wed, 27 Jan 2021 21:25:58 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 70A9864DA1 for ; Wed, 27 Jan 2021 21:25:57 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 70A9864DA1 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id D435E6B0006; Wed, 27 Jan 2021 16:25:56 -0500 (EST) Received: by kanga.kvack.org (Postfix, from userid 40) id D1C216B006E; Wed, 27 Jan 2021 16:25:56 -0500 (EST) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id BA60E6B0070; Wed, 27 Jan 2021 16:25:56 -0500 (EST) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0054.hostedemail.com [216.40.44.54]) by kanga.kvack.org (Postfix) with ESMTP id 9A1FF6B0006 for ; Wed, 27 Jan 2021 16:25:56 -0500 (EST) Received: from smtpin29.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 5BB1A180AD822 for ; Wed, 27 Jan 2021 21:25:56 +0000 (UTC) X-FDA: 77752837512.29.quiet48_1e088852759a Received: from filter.hostedemail.com (10.5.16.251.rfc1918.com [10.5.16.251]) by smtpin29.hostedemail.com (Postfix) with ESMTP id 2E04A180868F8 for ; Wed, 27 Jan 2021 21:25:56 +0000 (UTC) X-HE-Tag: quiet48_1e088852759a X-Filterd-Recvd-Size: 4693 Received: from mga09.intel.com (mga09.intel.com [134.134.136.24]) by imf27.hostedemail.com (Postfix) with ESMTP for ; Wed, 27 Jan 2021 21:25:54 +0000 (UTC) IronPort-SDR: QOeHNfWYnHCnCHpMzS6I517nRJLyXVQh8q0v4lrpMHsrMpEc7J+71hIqa3P5T4wZ0KJi4msG/P mJEzg3XLMEBQ== X-IronPort-AV: E=McAfee;i="6000,8403,9877"; a="180281092" X-IronPort-AV: E=Sophos;i="5.79,380,1602572400"; d="scan'208";a="180281092" Received: from orsmga003.jf.intel.com ([10.7.209.27]) by orsmga102.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 27 Jan 2021 13:25:49 -0800 IronPort-SDR: D4aDZfyvo1J+7UBhOQ49iNv7JhMiCuGG+vToy+qRFwayXLng2xzMnNfgwlbNXvFOqgPMTk+lub v9NRQYJZNB5g== X-IronPort-AV: E=Sophos;i="5.79,380,1602572400"; d="scan'208";a="353948187" Received: from yyu32-desk.sc.intel.com ([143.183.136.146]) by orsmga003-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 27 Jan 2021 13:25:48 -0800 From: Yu-cheng Yu 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 , Borislav Petkov , 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 , Dave Martin , Weijiang Yang , Pengfei Xu Cc: Yu-cheng Yu Subject: [PATCH v18 02/25] x86/cet/shstk: Add Kconfig option for user-mode control-flow protection Date: Wed, 27 Jan 2021 13:25:01 -0800 Message-Id: <20210127212524.10188-3-yu-cheng.yu@intel.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20210127212524.10188-1-yu-cheng.yu@intel.com> References: <20210127212524.10188-1-yu-cheng.yu@intel.com> MIME-Version: 1.0 Content-Transfer-Encoding: quoted-printable 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: Shadow Stack provides protection against function return address corruption. It is active when the processor supports it, the kernel has CONFIG_X86_CET enabled, and the application is built for the feature. This is only implemented for the 64-bit kernel. When it is enabled, lega= cy non-Shadow Stack applications continue to work, but without protection. Signed-off-by: Yu-cheng Yu --- arch/x86/Kconfig | 22 ++++++++++++++++++++++ arch/x86/Kconfig.assembler | 5 +++++ 2 files changed, 27 insertions(+) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 21f851179ff0..2d080a2335df 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -1951,6 +1951,28 @@ config X86_SGX =20 If unsure, say N. =20 +config ARCH_HAS_SHADOW_STACK + def_bool n + +config X86_CET + prompt "Intel Control-flow protection for user-mode" + def_bool n + depends on CPU_SUP_INTEL && X86_64 + depends on AS_WRUSS + select ARCH_USES_HIGH_VMA_FLAGS + select ARCH_HAS_SHADOW_STACK + help + Control-flow protection is a hardware security hardening feature + that detects function-return address or jump target changes by + malicious code. Applications must be enabled to use it, and old + userspace does not get protection "for free". + Support for this feature is present on processors released in + 2020 or later. Enabling this feature increases kernel text size + by 3.7 KB. + See Documentation/x86/intel_cet.rst for more information. + + If unsure, say N. + config EFI bool "EFI runtime service support" depends on ACPI diff --git a/arch/x86/Kconfig.assembler b/arch/x86/Kconfig.assembler index 26b8c08e2fc4..00c79dd93651 100644 --- a/arch/x86/Kconfig.assembler +++ b/arch/x86/Kconfig.assembler @@ -19,3 +19,8 @@ config AS_TPAUSE def_bool $(as-instr,tpause %ecx) help Supported by binutils >=3D 2.31.1 and LLVM integrated assembler >=3D = V7 + +config AS_WRUSS + def_bool $(as-instr,wrussq %rax$(comma)(%rbx)) + help + Supported by binutils >=3D 2.31 and LLVM integrated assembler --=20 2.21.0