From patchwork Fri Aug 20 18:22:44 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: 12450225 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 566FCC4338F for ; Fri, 20 Aug 2021 18:23:33 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 0744A6127C for ; Fri, 20 Aug 2021 18:23:33 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 0744A6127C 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 A13B48D0008; Fri, 20 Aug 2021 14:23:14 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 9748D8D0009; Fri, 20 Aug 2021 14:23:14 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 7EF468D0008; Fri, 20 Aug 2021 14:23:14 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0215.hostedemail.com [216.40.44.215]) by kanga.kvack.org (Postfix) with ESMTP id 37BE18D0009 for ; Fri, 20 Aug 2021 14:23:14 -0400 (EDT) Received: from smtpin34.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id DCEB918026B1B for ; Fri, 20 Aug 2021 18:23:13 +0000 (UTC) X-FDA: 78496281066.34.7E95DE8 Received: from mga01.intel.com (mga01.intel.com [192.55.52.88]) by imf25.hostedemail.com (Postfix) with ESMTP id 5979EB000180 for ; Fri, 20 Aug 2021 18:23:13 +0000 (UTC) X-IronPort-AV: E=McAfee;i="6200,9189,10082"; a="238949538" X-IronPort-AV: E=Sophos;i="5.84,338,1620716400"; d="scan'208";a="238949538" Received: from fmsmga003.fm.intel.com ([10.253.24.29]) by fmsmga101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 20 Aug 2021 11:23:10 -0700 X-IronPort-AV: E=Sophos;i="5.84,338,1620716400"; d="scan'208";a="523799181" 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 11:23:09 -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 09/10] x86/vdso/32: Add ENDBR to __kernel_vsyscall entry point Date: Fri, 20 Aug 2021 11:22:44 -0700 Message-Id: <20210820182245.1188-10-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 Authentication-Results: imf25.hostedemail.com; dkim=none; spf=none (imf25.hostedemail.com: domain of yu-cheng.yu@intel.com has no SPF policy when checking 192.55.52.88) smtp.mailfrom=yu-cheng.yu@intel.com; dmarc=fail reason="No valid SPF, No valid DKIM" header.from=intel.com (policy=none) X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: 5979EB000180 X-Stat-Signature: hkp3d4ekyqdjskfoq6q4wfzgngndujds X-HE-Tag: 1629483793-85257 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: From: "H.J. Lu" ENDBR is a special new instruction for the Indirect Branch Tracking (IBT) component of CET. IBT prevents attacks by ensuring that (most) indirect branches and function calls may only land at ENDBR instructions. Branches that don't follow the rules will result in control flow (#CF) exceptions. ENDBR is a noop when IBT is unsupported or disabled. Most ENDBR instructions are inserted automatically by the compiler, but branch targets written in assembly must have ENDBR added manually. Add that to __kernel_vsyscall entry point. Signed-off-by: H.J. Lu Signed-off-by: Yu-cheng Yu Reviewed-by: Kees Cook Cc: Andy Lutomirski --- arch/x86/entry/vdso/vdso32/system_call.S | 2 ++ 1 file changed, 2 insertions(+) diff --git a/arch/x86/entry/vdso/vdso32/system_call.S b/arch/x86/entry/vdso/vdso32/system_call.S index 6ddd7a937b3e..d321c2ded33a 100644 --- a/arch/x86/entry/vdso/vdso32/system_call.S +++ b/arch/x86/entry/vdso/vdso32/system_call.S @@ -7,6 +7,7 @@ #include #include #include +#include .text .globl __kernel_vsyscall @@ -14,6 +15,7 @@ ALIGN __kernel_vsyscall: CFI_STARTPROC + ENDBR32 /* * Reshuffle regs so that all of any of the entry instructions * will preserve enough state.