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=-3.9 required=3.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,HEADER_FROM_DIFFERENT_DOMAINS,MAILING_LIST_MULTI, SPF_HELO_NONE,SPF_PASS autolearn=no 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 24D3AC43464 for ; Mon, 21 Sep 2020 10:04:10 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id ADAFE221E2 for ; Mon, 21 Sep 2020 10:04:09 +0000 (UTC) Authentication-Results: mail.kernel.org; dkim=pass (1024-bit key) header.d=alien8.de header.i=@alien8.de header.b="C4UNaCAz" Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1726571AbgIUKEJ (ORCPT ); Mon, 21 Sep 2020 06:04:09 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:56466 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1726428AbgIUKEI (ORCPT ); Mon, 21 Sep 2020 06:04:08 -0400 Received: from mail.skyhub.de (mail.skyhub.de [IPv6:2a01:4f8:190:11c2::b:1457]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 6998DC061755 for ; Mon, 21 Sep 2020 03:04:08 -0700 (PDT) Received: from zn.tnic (p200300ec2f07e300a1766583a478f392.dip0.t-ipconnect.de [IPv6:2003:ec:2f07:e300:a176:6583:a478:f392]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by mail.skyhub.de (SuperMail on ZX Spectrum 128k) with ESMTPSA id A330E1EC0323; Mon, 21 Sep 2020 12:04:04 +0200 (CEST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=alien8.de; s=dkim; t=1600682644; h=from:from:reply-to:subject:subject:date:date:message-id:message-id: to:to:cc:cc:mime-version:mime-version:content-type:content-type: content-transfer-encoding:in-reply-to:in-reply-to: references:references; bh=1udGxMkFjeOfV8BEY6v5FP5Ybt85foi64B2PPrPSWuY=; b=C4UNaCAzsbKRZHDs/6SGErP8jpwET5CPKcp2z8WviAVsvwsAmOKv+llVqIWaLPSsIIiyml hl81akJ+0zpRqT4AO7VPJVCCF9/zbVu840ejXPuK502FGaV2LNVIFV4lXQ06SjKKRvc13g 5Kp7LSnXpmobWWEsa5olMKCUNn5YNlk= Date: Mon, 21 Sep 2020 12:03:56 +0200 From: Borislav Petkov To: Jarkko Sakkinen Cc: x86@kernel.org, linux-sgx@vger.kernel.org, linux-kernel@vger.kernel.org, Jethro Beekman , Haitao Huang , Chunyang Hui , Jordan Hand , Nathaniel McCallum , Seth Moore , Darren Kenny , Sean Christopherson , Suresh Siddha , akpm@linux-foundation.org, andriy.shevchenko@linux.intel.com, asapek@google.com, cedric.xing@intel.com, chenalexchen@google.com, conradparker@google.com, cyhanish@google.com, dave.hansen@intel.com, haitao.huang@intel.com, josh@joshtriplett.org, kai.huang@intel.com, kai.svahn@intel.com, kmoy@google.com, ludloff@google.com, luto@kernel.org, nhorman@redhat.com, puiterwijk@redhat.com, rientjes@google.com, tglx@linutronix.de, yaozhangx@google.com Subject: Re: [PATCH v38 12/24] x86/sgx: Add SGX_IOC_ENCLAVE_CREATE Message-ID: <20200921100356.GB5901@zn.tnic> References: <20200915112842.897265-1-jarkko.sakkinen@linux.intel.com> <20200915112842.897265-13-jarkko.sakkinen@linux.intel.com> MIME-Version: 1.0 Content-Type: text/plain; charset=utf-8 Content-Disposition: inline In-Reply-To: <20200915112842.897265-13-jarkko.sakkinen@linux.intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-sgx@vger.kernel.org On Tue, Sep 15, 2020 at 02:28:30PM +0300, Jarkko Sakkinen wrote: > +static int sgx_validate_secs(const struct sgx_secs *secs) > +{ > + u64 max_size = (secs->attributes & SGX_ATTR_MODE64BIT) ? > + sgx_encl_size_max_64 : sgx_encl_size_max_32; > + > + if (secs->size < (2 * PAGE_SIZE) || !is_power_of_2(secs->size)) > + return -EINVAL; > + > + if (secs->base & (secs->size - 1)) > + return -EINVAL; > + > + if (secs->miscselect & sgx_misc_reserved_mask || > + secs->attributes & sgx_attributes_reserved_mask || > + secs->xfrm & sgx_xfrm_reserved_mask) > + return -EINVAL; > + > + if (secs->size > max_size) > + return -EINVAL; > + > + if (!(secs->xfrm & XFEATURE_MASK_FP) || > + !(secs->xfrm & XFEATURE_MASK_SSE) || > + (((secs->xfrm >> XFEATURE_BNDREGS) & 1) != > + ((secs->xfrm >> XFEATURE_BNDCSR) & 1))) Let that last line stick out so that you have each statement on a single line. > + return -EINVAL; > + > + if (!secs->ssa_frame_size) > + return -EINVAL; > + > + if (sgx_calc_ssa_frame_size(secs->miscselect, secs->xfrm) > > + secs->ssa_frame_size) Let that stick out. > + return -EINVAL; > + > + if (memchr_inv(secs->reserved1, 0, sizeof(secs->reserved1)) || > + memchr_inv(secs->reserved2, 0, sizeof(secs->reserved2)) || > + memchr_inv(secs->reserved3, 0, sizeof(secs->reserved3)) || > + memchr_inv(secs->reserved4, 0, sizeof(secs->reserved4))) > + return -EINVAL; > + > + return 0; > +} > + > +static int sgx_encl_create(struct sgx_encl *encl, struct sgx_secs *secs) > +{ > + unsigned long encl_size = secs->size + PAGE_SIZE; You're still using secs->size before validation. I know, we will return early if sgx_validate_secs() fails but pls move that addition after the validation call. ... > +/** > + * sgx_ioc_enclave_create - handler for %SGX_IOC_ENCLAVE_CREATE > + * @filep: open file to /dev/sgx Dammit, how many times do I have to type this comment here?! "That's @encl: enclave pointer or so." There's no filep - there is an encl! > + * @arg: userspace pointer to a struct sgx_enclave_create instance > + * > + * Allocate kernel data structures for a new enclave and execute ECREATE after > + * verifying the correctness of the provided SECS. ... which is done in sgx_validate_secs()." Yes, spell it out, otherwise one has to wonder where that validation is happening in the function *below* because the comment is over it - not over sgx_validate_secs(). And yes, you need to spell stuff like that out because this SGX crap is complex and it better be properly documented! -- Regards/Gruss, Boris. https://people.kernel.org/tglx/notes-about-netiquette