From patchwork Fri Aug 20 18:22:36 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: 12450207 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 5658EC432BE for ; Fri, 20 Aug 2021 18:23:12 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 0A17861361 for ; Fri, 20 Aug 2021 18:23:12 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 0A17861361 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 94FB66B0072; Fri, 20 Aug 2021 14:23:11 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 8D9A58D0001; Fri, 20 Aug 2021 14:23:11 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 751586B0074; Fri, 20 Aug 2021 14:23:11 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0084.hostedemail.com [216.40.44.84]) by kanga.kvack.org (Postfix) with ESMTP id 3D8196B0072 for ; Fri, 20 Aug 2021 14:23:11 -0400 (EDT) Received: from smtpin01.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id E388728DAA for ; Fri, 20 Aug 2021 18:23:10 +0000 (UTC) X-FDA: 78496280940.01.F013C86 Received: from mga03.intel.com (mga03.intel.com [134.134.136.65]) by imf27.hostedemail.com (Postfix) with ESMTP id 4CB957000091 for ; Fri, 20 Aug 2021 18:23:10 +0000 (UTC) X-IronPort-AV: E=McAfee;i="6200,9189,10082"; a="216854480" X-IronPort-AV: E=Sophos;i="5.84,338,1620716400"; d="scan'208";a="216854480" Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by orsmga103.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 Aug 2021 11:23:07 -0700 X-IronPort-AV: E=Sophos;i="5.84,338,1620716400"; d="scan'208";a="523799153" 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; 20 Aug 2021 11:23:07 -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 v29 01/10] x86/cet/ibt: Add Kconfig option for Indirect Branch Tracking Date: Fri, 20 Aug 2021 11:22:36 -0700 Message-Id: <20210820182245.1188-2-yu-cheng.yu@intel.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20210820182245.1188-1-yu-cheng.yu@intel.com> References: <20210820182245.1188-1-yu-cheng.yu@intel.com> MIME-Version: 1.0 X-Rspamd-Queue-Id: 4CB957000091 Authentication-Results: imf27.hostedemail.com; dkim=none; dmarc=fail reason="No valid SPF, No valid DKIM" header.from=intel.com (policy=none); spf=none (imf27.hostedemail.com: domain of yu-cheng.yu@intel.com has no SPF policy when checking 134.134.136.65) smtp.mailfrom=yu-cheng.yu@intel.com X-Rspamd-Server: rspam04 X-Stat-Signature: nun5woudk8kqwh3o759dyegr75gn9gkj X-HE-Tag: 1629483790-323610 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 34692f02118c..b063d6d2491f 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -1932,6 +1932,25 @@ 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)