From patchwork Tue Mar 16 15:13:17 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: 12142429 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 6AEA8C2BB53 for ; Tue, 16 Mar 2021 15:13:44 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 1161F64E98 for ; Tue, 16 Mar 2021 15:13:44 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 1161F64E98 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=intel.com Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 1BCD88D000E; Tue, 16 Mar 2021 11:13:40 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 196048D0002; Tue, 16 Mar 2021 11:13:40 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id F02C38D000F; Tue, 16 Mar 2021 11:13:39 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0112.hostedemail.com [216.40.44.112]) by kanga.kvack.org (Postfix) with ESMTP id C49F08D0002 for ; Tue, 16 Mar 2021 11:13:39 -0400 (EDT) Received: from smtpin25.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 3952B75A0 for ; Tue, 16 Mar 2021 15:13:39 +0000 (UTC) X-FDA: 77926081758.25.D323AB1 Received: from mga01.intel.com (mga01.intel.com [192.55.52.88]) by imf19.hostedemail.com (Postfix) with ESMTP id 4949190009F6 for ; Tue, 16 Mar 2021 15:13:36 +0000 (UTC) IronPort-SDR: beUwAP3rcnXMbH5kgmvapf/9vM/q7RT0naWXPxk7EYoFkB7/g8hF2HNmp4RXKZBPbyU1YtOcDt hxHblEtToVaA== X-IronPort-AV: E=McAfee;i="6000,8403,9924"; a="209213143" X-IronPort-AV: E=Sophos;i="5.81,251,1610438400"; d="scan'208";a="209213143" Received: from orsmga001.jf.intel.com ([10.7.209.18]) by fmsmga101.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Mar 2021 08:13:31 -0700 IronPort-SDR: XMUGFtokid+XPAH9VQHcrNL+ZV5UltfjoavGNjyXATpoL0I04trswapBg305eszfrbRqEB0FEF hjkTLoWaawWw== X-IronPort-AV: E=Sophos;i="5.81,251,1610438400"; d="scan'208";a="449749007" Received: from yyu32-desk.sc.intel.com ([143.183.136.146]) by orsmga001-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 16 Mar 2021 08:13:30 -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 Cc: Yu-cheng Yu Subject: [PATCH v23 7/9] x86/vdso/32: Add ENDBR to __kernel_vsyscall entry point Date: Tue, 16 Mar 2021 08:13:17 -0700 Message-Id: <20210316151320.6123-8-yu-cheng.yu@intel.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20210316151320.6123-1-yu-cheng.yu@intel.com> References: <20210316151320.6123-1-yu-cheng.yu@intel.com> MIME-Version: 1.0 X-Stat-Signature: 31nbaxgp6ddcr5u5wcdgnwz54n11cnom X-Rspamd-Server: rspam01 X-Rspamd-Queue-Id: 4949190009F6 Received-SPF: none (intel.com>: No applicable sender policy available) receiver=imf19; identity=mailfrom; envelope-from=""; helo=mga01.intel.com; client-ip=192.55.52.88 X-HE-DKIM-Result: none/none X-HE-Tag: 1615907616-436447 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 Cc: Andy Lutomirski Cc: Kees Cook --- 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 de1fff7188aa..adbe948c1a81 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 "../../calling.h" .text .globl __kernel_vsyscall @@ -14,6 +15,7 @@ ALIGN __kernel_vsyscall: CFI_STARTPROC + ENDBR /* * Reshuffle regs so that all of any of the entry instructions * will preserve enough state.