From patchwork Mon Aug 30 18:22:21 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: 12465783 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 964FBC4320E for ; Mon, 30 Aug 2021 18:23:20 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 4ACE760FA0 for ; Mon, 30 Aug 2021 18:23:20 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.4.1 mail.kernel.org 4ACE760FA0 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 031468D0002; Mon, 30 Aug 2021 14:23:14 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id F22AD6B0082; Mon, 30 Aug 2021 14:23:13 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id DA98A8D0002; Mon, 30 Aug 2021 14:23:13 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0125.hostedemail.com [216.40.44.125]) by kanga.kvack.org (Postfix) with ESMTP id CAF3E6B0080 for ; Mon, 30 Aug 2021 14:23:13 -0400 (EDT) Received: from smtpin36.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay04.hostedemail.com (Postfix) with ESMTP id 8147526DF0 for ; Mon, 30 Aug 2021 18:23:13 +0000 (UTC) X-FDA: 78532569066.36.FAB023F Received: from mga02.intel.com (mga02.intel.com [134.134.136.20]) by imf14.hostedemail.com (Postfix) with ESMTP id A321B6001986 for ; Mon, 30 Aug 2021 18:23:12 +0000 (UTC) X-IronPort-AV: E=McAfee;i="6200,9189,10092"; a="205547535" X-IronPort-AV: E=Sophos;i="5.84,364,1620716400"; d="scan'208";a="205547535" Received: from fmsmga002.fm.intel.com ([10.253.24.26]) by orsmga101.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Aug 2021 11:23:11 -0700 X-IronPort-AV: E=Sophos;i="5.84,364,1620716400"; d="scan'208";a="540650971" Received: from yyu32-desk.sc.intel.com ([143.183.136.146]) by fmsmga002-auth.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 30 Aug 2021 11:23:11 -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 , Jarkko Sakkinen Subject: [PATCH v30 10/10] x86/vdso: Add ENDBR to __vdso_sgx_enter_enclave Date: Mon, 30 Aug 2021 11:22:21 -0700 Message-Id: <20210830182221.3535-11-yu-cheng.yu@intel.com> X-Mailer: git-send-email 2.21.0 In-Reply-To: <20210830182221.3535-1-yu-cheng.yu@intel.com> References: <20210830182221.3535-1-yu-cheng.yu@intel.com> MIME-Version: 1.0 Authentication-Results: imf14.hostedemail.com; dkim=none; dmarc=fail reason="No valid SPF, No valid DKIM" header.from=intel.com (policy=none); spf=none (imf14.hostedemail.com: domain of yu-cheng.yu@intel.com has no SPF policy when checking 134.134.136.20) smtp.mailfrom=yu-cheng.yu@intel.com X-Rspamd-Server: rspam06 X-Rspamd-Queue-Id: A321B6001986 X-Stat-Signature: o5gywf9reamxkytof7o3kfyfuwhshdhp X-HE-Tag: 1630347792-991615 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: 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 ENDBR to __vdso_sgx_enter_enclave() indirect branch targets, including EEXIT, which is considered an indirect branch. Signed-off-by: Yu-cheng Yu Reviewed-by: Kees Cook Acked-by: Jarkko Sakkinen Cc: Andy Lutomirski Cc: Borislav Petkov Cc: Dave Hansen Cc: Peter Zijlstra --- v28: - Move ENDBR64 below EEXIT comment (no functional change). - Update change log, state EEXIT is considered an indirect branch. --- arch/x86/entry/vdso/vsgx.S | 4 ++++ 1 file changed, 4 insertions(+) diff --git a/arch/x86/entry/vdso/vsgx.S b/arch/x86/entry/vdso/vsgx.S index 99dafac992e2..d65a7f9dea8b 100644 --- a/arch/x86/entry/vdso/vsgx.S +++ b/arch/x86/entry/vdso/vsgx.S @@ -4,6 +4,7 @@ #include #include #include +#include #include "extable.h" @@ -27,6 +28,7 @@ SYM_FUNC_START(__vdso_sgx_enter_enclave) /* Prolog */ .cfi_startproc + ENDBR64 push %rbp .cfi_adjust_cfa_offset 8 .cfi_rel_offset %rbp, 0 @@ -64,6 +66,7 @@ SYM_FUNC_START(__vdso_sgx_enter_enclave) enclu /* EEXIT jumps here unless the enclave is doing something fancy. */ + ENDBR64 mov SGX_ENCLAVE_OFFSET_OF_RUN(%rbp), %rbx /* Set exit_reason. */ @@ -91,6 +94,7 @@ SYM_FUNC_START(__vdso_sgx_enter_enclave) jmp .Lout .Lhandle_exception: + ENDBR64 mov SGX_ENCLAVE_OFFSET_OF_RUN(%rbp), %rbx /* Set the exception info. */