From mboxrd@z Thu Jan 1 00:00:00 1970 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=-16.2 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED 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 E3F9CC433E0 for ; Tue, 16 Mar 2021 19:23:14 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 60E8A6507D for ; Tue, 16 Mar 2021 19:23:14 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 60E8A6507D Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=kernel.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id B52CE6B006C; Tue, 16 Mar 2021 15:23:13 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id B2A4C6B006E; Tue, 16 Mar 2021 15:23:13 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 9F37D6B0070; Tue, 16 Mar 2021 15:23:13 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0147.hostedemail.com [216.40.44.147]) by kanga.kvack.org (Postfix) with ESMTP id 83B296B006C for ; Tue, 16 Mar 2021 15:23:13 -0400 (EDT) Received: from smtpin01.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay01.hostedemail.com (Postfix) with ESMTP id 3A16A180AD81F for ; Tue, 16 Mar 2021 19:23:13 +0000 (UTC) X-FDA: 77926710666.01.B9DCCF9 Received: from mail.kernel.org (mail.kernel.org [198.145.29.99]) by imf17.hostedemail.com (Postfix) with ESMTP id A93DD4080F4A for ; Tue, 16 Mar 2021 19:23:12 +0000 (UTC) Received: by mail.kernel.org (Postfix) with ESMTPSA id 4A8146505E; Tue, 16 Mar 2021 19:23:11 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1615922591; bh=sWtZmKfMXGF5SI475qI69+xO3GMtSBC6a8W35/layQ4=; h=Date:From:To:Cc:Subject:References:In-Reply-To:From; b=rFWewSgAfHeRhxbl6tLAZ+SmyfaPJv6fHztLMoMKe/3REKkyu/EzU3gxj7gTQyz4+ zFYssQKI7x1yKN+UQlVF5n2OIAaOVNqkctIoyYLcV2NZpuHcGu0nn11MN/6Loca+8K +omIRhM+uvATCZauV2ta+4+NH9hy7rewWPrud9nuG7TgFqKpIJCyttIGHO1e0ntePD y9FVEWng7pDIw9Vk2Bj1YVJmGEhaJgNrLaTtEcQ0tFS9p3CPOfQ6jnXH/04f2hYVRT yow0OhI6XTkpQ1cpaKVryptk+7DUMwPmqx+e30iNUdCAQ/r8Y6WA5zUSr9L3/uGdpM 3Z8emdSM2pqFg== Date: Tue, 16 Mar 2021 21:22:46 +0200 From: Jarkko Sakkinen To: Yu-cheng Yu Cc: 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 Subject: Re: [PATCH v23 9/9] x86/vdso: Add ENDBR to __vdso_sgx_enter_enclave Message-ID: References: <20210316151320.6123-1-yu-cheng.yu@intel.com> <20210316151320.6123-10-yu-cheng.yu@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210316151320.6123-10-yu-cheng.yu@intel.com> X-Stat-Signature: p6nboyiisykc55jwr7kgt9pzcdqbn1mi X-Rspamd-Server: rspam05 X-Rspamd-Queue-Id: A93DD4080F4A Received-SPF: none (kernel.org>: No applicable sender policy available) receiver=imf17; identity=mailfrom; envelope-from=""; helo=mail.kernel.org; client-ip=198.145.29.99 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1615922592-420717 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: On Tue, Mar 16, 2021 at 08:13:19AM -0700, Yu-cheng Yu wrote: > 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() branch targets. > > Signed-off-by: Yu-cheng Yu > Cc: Andy Lutomirski > Cc: Borislav Petkov > Cc: Dave Hansen > Cc: Jarkko Sakkinen > Cc: Peter Zijlstra > --- > 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 86a0e94f68df..1baa9b49053e 100644 > --- a/arch/x86/entry/vdso/vsgx.S > +++ b/arch/x86/entry/vdso/vsgx.S > @@ -6,6 +6,7 @@ > #include > > #include "extable.h" > +#include "../calling.h" > > /* Relative to %rbp. */ > #define SGX_ENCLAVE_OFFSET_OF_RUN 16 > @@ -27,6 +28,7 @@ > SYM_FUNC_START(__vdso_sgx_enter_enclave) > /* Prolog */ > .cfi_startproc > + ENDBR > push %rbp > .cfi_adjust_cfa_offset 8 > .cfi_rel_offset %rbp, 0 > @@ -62,6 +64,7 @@ SYM_FUNC_START(__vdso_sgx_enter_enclave) > .Lasync_exit_pointer: > .Lenclu_eenter_eresume: > enclu > + ENDBR > > /* EEXIT jumps here unless the enclave is doing something fancy. */ > mov SGX_ENCLAVE_OFFSET_OF_RUN(%rbp), %rbx > @@ -91,6 +94,7 @@ SYM_FUNC_START(__vdso_sgx_enter_enclave) > jmp .Lout > > .Lhandle_exception: > + ENDBR > mov SGX_ENCLAVE_OFFSET_OF_RUN(%rbp), %rbx > > /* Set the exception info. */ > -- > 2.21.0 > > Looks good to me. Reviewed-by: Jarkko Sakkinen /Jarkko