From patchwork Thu Jul 22 20:57:14 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Yu-cheng Yu X-Patchwork-Id: 12394767 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 597C2C19F2F for ; Thu, 22 Jul 2021 20:58:17 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 0411560EBE for ; Thu, 22 Jul 2021 20:58:17 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 0411560EBE 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 738B28E0001; Thu, 22 Jul 2021 16:58:10 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 6739D8E0003; Thu, 22 Jul 2021 16:58:10 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 400F68E0001; Thu, 22 Jul 2021 16:58:10 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0002.hostedemail.com [216.40.44.2]) by kanga.kvack.org (Postfix) with ESMTP id 129188E0002 for ; Thu, 22 Jul 2021 16:58:10 -0400 (EDT) Received: from smtpin37.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id C9F2523E57 for ; Thu, 22 Jul 2021 20:58:09 +0000 (UTC) X-FDA: 78391436298.37.1B05DBC Received: from mga12.intel.com (mga12.intel.com [192.55.52.136]) by imf19.hostedemail.com (Postfix) with ESMTP id 22C19B000C0F for ; Thu, 22 Jul 2021 20:58:08 +0000 (UTC) X-IronPort-AV: E=McAfee;i="6200,9189,10053"; a="191330058" X-IronPort-AV: E=Sophos;i="5.84,262,1620716400"; d="scan'208";a="191330058" Received: from fmsmga007.fm.intel.com ([10.253.24.52]) by fmsmga106.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Jul 2021 13:58:03 -0700 X-IronPort-AV: E=Sophos;i="5.84,262,1620716400"; d="scan'208";a="433273358" Received: from yyu32-desk.sc.intel.com ([143.183.136.146]) by fmsmga007-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 22 Jul 2021 13:58:03 -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" , Dave Martin , Weijiang Yang , Pengfei Xu , Haitao Huang , Rick P Edgecombe Cc: Yu-cheng Yu Subject: [PATCH v28 01/10] x86/cet/ibt: Add Kconfig option for Indirect Branch Tracking Date: Thu, 22 Jul 2021 13:57:14 -0700 Message-Id: <20210722205723.9476-2-yu-cheng.yu@intel.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20210722205723.9476-1-yu-cheng.yu@intel.com> References: <20210722205723.9476-1-yu-cheng.yu@intel.com> MIME-Version: 1.0 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 192.55.52.136) smtp.mailfrom=yu-cheng.yu@intel.com X-Rspamd-Server: rspam03 X-Rspamd-Queue-Id: 22C19B000C0F X-Stat-Signature: 1r91m1qbb6apsbaomj4uzbhiwirbceby X-HE-Tag: 1626987488-694683 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: Indirect Branch Tracking (IBT) provides protection against CALL-/JMP- oriented programming attacks. It is active when the kernel has this feature enabled, and the processor and the application support it. When this feature is enabled, legacy non-IBT applications continue to work, but without IBT protection. Signed-off-by: Yu-cheng Yu Reviewed-by: Kees Cook --- arch/x86/Kconfig | 19 +++++++++++++++++++ arch/x86/include/asm/disabled-features.h | 8 +++++++- 2 files changed, 26 insertions(+), 1 deletion(-) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 7a2991457497..8f0bba206206 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -1933,6 +1933,25 @@ config X86_SHADOW_STACK If unsure, say N. +config X86_IBT + prompt "Intel Indirect Branch Tracking" + def_bool n + depends on X86_SHADOW_STACK + depends on $(cc-option,-fcf-protection) + help + Indirect Branch Tracking (IBT) provides protection against + CALL-/JMP-oriented programming attacks. It is active when + the kernel has this feature enabled, and the processor and + the application support it. When this feature is enabled, + legacy non-IBT applications continue to work, but without + IBT protection. + 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/include/asm/disabled-features.h b/arch/x86/include/asm/disabled-features.h index b7728f7afb2b..e3a08fcd72f4 100644 --- a/arch/x86/include/asm/disabled-features.h +++ b/arch/x86/include/asm/disabled-features.h @@ -71,6 +71,12 @@ #define DISABLE_SHSTK (1 << (X86_FEATURE_SHSTK & 31)) #endif +#ifdef CONFIG_X86_IBT +#define DISABLE_IBT 0 +#else +#define DISABLE_IBT (1 << (X86_FEATURE_IBT & 31)) +#endif + /* * Make sure to add features to the correct mask */ @@ -93,7 +99,7 @@ #define DISABLED_MASK16 (DISABLE_PKU|DISABLE_OSPKE|DISABLE_LA57|DISABLE_UMIP| \ DISABLE_ENQCMD|DISABLE_SHSTK) #define DISABLED_MASK17 0 -#define DISABLED_MASK18 0 +#define DISABLED_MASK18 (DISABLE_IBT) #define DISABLED_MASK19 0 #define DISABLED_MASK_CHECK BUILD_BUG_ON_ZERO(NCAPINTS != 20)