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=-16.8 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 24A41C4338F for ; Thu, 22 Jul 2021 20:53:03 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id C4F0F60EB2 for ; Thu, 22 Jul 2021 20:53:02 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org C4F0F60EB2 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=kvack.org Received: by kanga.kvack.org (Postfix) id 6EEA36B005D; Thu, 22 Jul 2021 16:53:01 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 6740E6B006C; Thu, 22 Jul 2021 16:53:01 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 4EF036B0071; Thu, 22 Jul 2021 16:53:01 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0092.hostedemail.com [216.40.44.92]) by kanga.kvack.org (Postfix) with ESMTP id 33E5B6B005D for ; Thu, 22 Jul 2021 16:53:01 -0400 (EDT) Received: from smtpin06.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id D240B211DD for ; Thu, 22 Jul 2021 20:53:00 +0000 (UTC) X-FDA: 78391423320.06.FB123DC Received: from mga04.intel.com (mga04.intel.com [192.55.52.120]) by imf19.hostedemail.com (Postfix) with ESMTP id 4F376B000C08 for ; Thu, 22 Jul 2021 20:53:00 +0000 (UTC) X-IronPort-AV: E=McAfee;i="6200,9189,10053"; a="209845041" X-IronPort-AV: E=Sophos;i="5.84,262,1620716400"; d="scan'208";a="209845041" Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga104.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Jul 2021 13:52:57 -0700 X-IronPort-AV: E=Sophos;i="5.84,262,1620716400"; d="scan'208";a="502035412" Received: from yyu32-desk.sc.intel.com ([143.183.136.146]) by fmsmga003-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Jul 2021 13:52:57 -0700 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 , Haitao Huang , Rick P Edgecombe Cc: Yu-cheng Yu Subject: [PATCH v28 02/32] x86/cet/shstk: Add Kconfig option for Shadow Stack Date: Thu, 22 Jul 2021 13:51:49 -0700 Message-Id: <20210722205219.7934-3-yu-cheng.yu@intel.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20210722205219.7934-1-yu-cheng.yu@intel.com> References: <20210722205219.7934-1-yu-cheng.yu@intel.com> MIME-Version: 1.0 X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: 4F376B000C08 X-Stat-Signature: c35pdad4fp71yprjno6k56h5snxy1y6e Authentication-Results: imf19.hostedemail.com; dkim=none; dmarc=fail reason="No valid SPF, No valid DKIM" header.from=intel.com (policy=none); spf=none (imf19.hostedemail.com: domain of yu-cheng.yu@intel.com has no SPF policy when checking 192.55.52.120) smtp.mailfrom=yu-cheng.yu@intel.com X-HE-Tag: 1626987180-347987 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_SHADOW_STACK enabled, and the application is built for the feature. This is only implemented for the 64-bit kernel. When it is enabled, legacy non-Shadow Stack applications continue to work, but witho= ut protection. Signed-off-by: Yu-cheng Yu Cc: Kees Cook --- v25: - Remove X86_CET and use X86_SHADOW_STACK directly. v24: - Update for the splitting X86_CET to X86_SHADOW_STACK and X86_IBT. 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 49270655e827..de992d3408b2 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -26,6 +26,7 @@ config X86_64 depends on 64BIT # Options that are inherently 64-bit kernel only: select ARCH_HAS_GIGANTIC_PAGE + select ARCH_HAS_SHADOW_STACK select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 select ARCH_USE_CMPXCHG_LOCKREF select HAVE_ARCH_SOFT_DIRTY @@ -1909,6 +1910,27 @@ config X86_SGX =20 If unsure, say N. =20 +config ARCH_HAS_SHADOW_STACK + def_bool n + +config X86_SHADOW_STACK + prompt "Intel Shadow Stack" + def_bool n + depends on AS_WRUSS + depends on ARCH_HAS_SHADOW_STACK + select ARCH_USES_HIGH_VMA_FLAGS + help + Shadow Stack protection is a hardware feature that detects function + return address corruption. This helps mitigate ROP attacks. + Applications must be enabled to use it, and old userspace does not + get protection "for free". + Support for this feature is present on Tiger Lake family of + 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