From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.2 (2018-09-13) on archive.lwn.net X-Spam-Level: X-Spam-Status: No, score=-5.7 required=5.0 tests=HEADER_FROM_DIFFERENT_DOMAINS, MAILING_LIST_MULTI,RCVD_IN_DNSWL_HI,SPF_HELO_NONE,SPF_NONE autolearn=unavailable autolearn_force=no version=3.4.2 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by archive.lwn.net (Postfix) with ESMTP id A07247D9ED for ; Tue, 13 Aug 2019 21:04:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1727455AbfHMVEf (ORCPT ); Tue, 13 Aug 2019 17:04:35 -0400 Received: from mga09.intel.com ([134.134.136.24]:18658 "EHLO mga09.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1727215AbfHMVDl (ORCPT ); Tue, 13 Aug 2019 17:03:41 -0400 X-Amp-Result: SKIPPED(no attachment in message) X-Amp-File-Uploaded: False Received: from fmsmga001.fm.intel.com ([10.253.24.23]) by orsmga102.jf.intel.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 13 Aug 2019 14:03:40 -0700 X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.64,382,1559545200"; d="scan'208";a="194275975" Received: from yyu32-desk1.sc.intel.com ([10.144.153.205]) by fmsmga001.fm.intel.com with ESMTP; 13 Aug 2019 14:03:40 -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 Cc: Yu-cheng Yu Subject: [PATCH v8 05/14] x86/cet/ibt: ELF header parsing for IBT Date: Tue, 13 Aug 2019 13:53:50 -0700 Message-Id: <20190813205359.12196-6-yu-cheng.yu@intel.com> X-Mailer: git-send-email 2.17.1 In-Reply-To: <20190813205359.12196-1-yu-cheng.yu@intel.com> References: <20190813205359.12196-1-yu-cheng.yu@intel.com> Sender: linux-doc-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-doc@vger.kernel.org Look in .note.gnu.property of an ELF file and check if Indirect Branch Tracking needs to be enabled for the task. Signed-off-by: Yu-cheng Yu --- arch/x86/Kconfig | 1 + arch/x86/kernel/process_64.c | 5 +++++ 2 files changed, 6 insertions(+) diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig index 666dc66a382e..7edb544cef00 100644 --- a/arch/x86/Kconfig +++ b/arch/x86/Kconfig @@ -1971,6 +1971,7 @@ config X86_INTEL_BRANCH_TRACKING_USER select X86_INTEL_CET select ARCH_HAS_AS_LIMIT select ARCH_USE_GNU_PROPERTY + select ARCH_BINFMT_ELF_STATE ---help--- Indirect Branch Tracking provides hardware protection against return-/jmp- oriented programming attacks. diff --git a/arch/x86/kernel/process_64.c b/arch/x86/kernel/process_64.c index 7ec60b14e96d..a051cfc5242f 100644 --- a/arch/x86/kernel/process_64.c +++ b/arch/x86/kernel/process_64.c @@ -856,6 +856,11 @@ int arch_setup_property(struct arch_elf_state *state) return r; } + if (cpu_feature_enabled(X86_FEATURE_IBT)) { + if (state->gnu_property & GNU_PROPERTY_X86_FEATURE_1_IBT) + r = cet_setup_ibt(); + } + return r; } #endif -- 2.17.1