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=-11.0 required=3.0 tests=BAYES_00,DKIMWL_WL_HIGH, DKIM_SIGNED,DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS, INCLUDES_CR_TRAILER,MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS 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 27CA3C43460 for ; Wed, 28 Apr 2021 20:39:47 +0000 (UTC) Received: from kanga.kvack.org (kanga.kvack.org [205.233.56.17]) by mail.kernel.org (Postfix) with ESMTP id 8AD0161444 for ; Wed, 28 Apr 2021 20:39:46 +0000 (UTC) DMARC-Filter: OpenDMARC Filter v1.3.2 mail.kernel.org 8AD0161444 Authentication-Results: mail.kernel.org; dmarc=fail (p=none dis=none) header.from=chromium.org Authentication-Results: mail.kernel.org; spf=pass smtp.mailfrom=owner-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix) id 90C4E6B0070; Wed, 28 Apr 2021 16:39:44 -0400 (EDT) Received: by kanga.kvack.org (Postfix, from userid 40) id 794D86B0073; Wed, 28 Apr 2021 16:39:44 -0400 (EDT) X-Delivered-To: int-list-linux-mm@kvack.org Received: by kanga.kvack.org (Postfix, from userid 63042) id 487356B0071; Wed, 28 Apr 2021 16:39:44 -0400 (EDT) X-Delivered-To: linux-mm@kvack.org Received: from forelay.hostedemail.com (smtprelay0130.hostedemail.com [216.40.44.130]) by kanga.kvack.org (Postfix) with ESMTP id 2752F6B0070 for ; Wed, 28 Apr 2021 16:39:41 -0400 (EDT) Received: from smtpin02.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay03.hostedemail.com (Postfix) with ESMTP id 81033824999B for ; Wed, 28 Apr 2021 20:39:40 +0000 (UTC) X-FDA: 78082941720.02.AB1B114 Received: from smtprelay.test.hostedemail.com (mail.test.hostedemail.com [216.40.41.5]) by imf05.hostedemail.com (Postfix) with ESMTP id B4CA6E000111 for ; Wed, 28 Apr 2021 20:39:37 +0000 (UTC) Received: from forelay.test.hostedemail.com (10.5.29.251.rfc1918.com [10.5.29.251]) by smtprelay01.test.hostedemail.com (Postfix) with ESMTP id C258A11CEC for ; Wed, 28 Apr 2021 20:39:39 +0000 (UTC) Received: from forelay.prod.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by fograve01.test.hostedemail.com (Postfix) with ESMTP id 9EF3623810 for ; Wed, 28 Apr 2021 20:39:39 +0000 (UTC) Received: from smtpin34.hostedemail.com (10.5.19.251.rfc1918.com [10.5.19.251]) by forelay02.hostedemail.com (Postfix) with ESMTP id 833834DCB for ; Wed, 28 Apr 2021 20:39:29 +0000 (UTC) X-FDA: 78082941258.34.D1909A6 Received: from mail-pg1-f177.google.com (mail-pg1-f177.google.com [209.85.215.177]) by imf16.hostedemail.com (Postfix) with ESMTP id A183C80192F6 for ; Wed, 28 Apr 2021 20:39:24 +0000 (UTC) Received: by mail-pg1-f177.google.com with SMTP id d10so7218389pgf.12 for ; Wed, 28 Apr 2021 13:39:28 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=chromium.org; s=google; h=date:from:to:cc:subject:message-id:references:mime-version :content-disposition:in-reply-to; bh=bP0jsyLUeBZMcia9mVsWBqP6zFcasRiNfS5tk4kM0rM=; b=A8+FVi1mPar4WLP24ObFpp1Q218abKlV0OQrmnoXUgmmTraergbRvRIY1olI2H8FM5 Zs2ESIBKBScQGKK1e8f+Sa1YgkVnUJgNUswDh4G4ZG1eWdx+7ssZlBxd43RQhC93UIcT UKYW2k8b4p/NrYoP+17PCBkBmkSnwJZS6FulQ= X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:date:from:to:cc:subject:message-id:references :mime-version:content-disposition:in-reply-to; bh=bP0jsyLUeBZMcia9mVsWBqP6zFcasRiNfS5tk4kM0rM=; b=Dyfwarm4ovaeQGV0KAtFrwWGb/3U5iQMOKcR4uKYp2JbyuJEeIXK0zBezGrXFAfUK1 JXGyjs8BEI07z2I5V2pHaYHHf3d2NPxdJIAu/H+Q6WGX7iGSxTcPcOLhDzIQba69qcKx UudqbwCCFPIE61KYIYIU75QPoFD2g783GnlDJOdMQIh6bTH967d/Ffb4PRZJbocXAp6r ebFf9nODhH16mUHo4o280SEA8v1Nu3SMsySykmMk6PohpWfARy/NorWG6z5Xl0QNK6n1 9NOHm5NfYpJ2Saz2GFnWnbGjCk/u25lpjBHrLUMpDKpgX929AuUMweshevaHZob9XB3H QC8g== X-Gm-Message-State: AOAM5310zttDlaq631rhuzwJVxclL41NW6QZ2goHxm6TMrtqU+gscfOf JOLgGz1ClqQbxryD2JFAV+GjCw== X-Google-Smtp-Source: ABdhPJz7TORt5UPUxQHJtcwUy7DLeU9h16cX0ZufDjJxSEVTidsxEub3MlR7oNmOUCLjsAVtm6Bv+w== X-Received: by 2002:a62:cd83:0:b029:275:d87e:612e with SMTP id o125-20020a62cd830000b0290275d87e612emr18839700pfg.49.1619642368304; Wed, 28 Apr 2021 13:39:28 -0700 (PDT) Received: from www.outflux.net (smtp.outflux.net. [198.145.64.163]) by smtp.gmail.com with ESMTPSA id l18sm5405576pjq.33.2021.04.28.13.39.27 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Wed, 28 Apr 2021 13:39:27 -0700 (PDT) Date: Wed, 28 Apr 2021 13:39:26 -0700 From: Kees Cook 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 , 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 , Jarkko Sakkinen Subject: Re: [PATCH v26 9/9] x86/vdso: Add ENDBR to __vdso_sgx_enter_enclave Message-ID: <202104281339.E21514F9D@keescook> References: <20210427204720.25007-1-yu-cheng.yu@intel.com> <20210427204720.25007-10-yu-cheng.yu@intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20210427204720.25007-10-yu-cheng.yu@intel.com> Received-SPF: none (chromium.org>: No applicable sender policy available) receiver=imf16; identity=mailfrom; envelope-from=""; helo=mail-pg1-f177.google.com; client-ip=209.85.215.177 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1619642364-444371 X-Stat-Signature: 7twu5hhoiyeu7hb8c6ikr8a6p1ubtxco X-Rspamd-Server: rspam04 X-Rspamd-Queue-Id: B4CA6E000111 Received-SPF: none (chromium.org>: No applicable sender policy available) receiver=imf05; identity=mailfrom; envelope-from=""; helo=smtprelay.test.hostedemail.com; client-ip=216.40.41.5 X-HE-DKIM-Result: pass/pass X-HE-Tag: 1619642377-717708 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, Apr 27, 2021 at 01:47:20PM -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 Reviewed-by: Kees Cook -- Kees Cook