From patchwork Fri Mar 4 09:35:06 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Jarkko Sakkinen X-Patchwork-Id: 12768849 Return-Path: X-Spam-Checker-Version: SpamAssassin 3.4.0 (2014-02-07) on aws-us-west-2-korg-lkml-1.web.codeaurora.org Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by smtp.lore.kernel.org (Postfix) with ESMTP id A7424C433FE for ; Fri, 4 Mar 2022 09:39:17 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S239215AbiCDJjr (ORCPT ); Fri, 4 Mar 2022 04:39:47 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:54752 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S239367AbiCDJiE (ORCPT ); Fri, 4 Mar 2022 04:38:04 -0500 Received: from ams.source.kernel.org (ams.source.kernel.org [145.40.68.75]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 68B991AC284; Fri, 4 Mar 2022 01:36:48 -0800 (PST) Received: from smtp.kernel.org (relay.kernel.org [52.25.139.140]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (No client certificate requested) by ams.source.kernel.org (Postfix) with ESMTPS id 4DD8EB827BE; Fri, 4 Mar 2022 09:36:47 +0000 (UTC) Received: by smtp.kernel.org (Postfix) with ESMTPSA id B8D75C340E9; Fri, 4 Mar 2022 09:36:45 +0000 (UTC) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=kernel.org; s=k20201202; t=1646386606; bh=q8pqqOEI7ayWuSh5x4Y1jlB8BVxBB20xk/YPxulohaY=; h=From:To:Cc:Subject:Date:In-Reply-To:References:From; b=f7n1UFcN/J0zCiEl/D83rTS0ODcmTuUY/1xKn3quJD9iaFrROzg/DQZfvWqHFPyrB T84pqn+NymP2bICBF2JfsD+3H9gQqmkWMYDUXbkL1HoC+Rvy6t1UYuxCgRcA8w8INb wstW9A9jcuwrTYBbDIg1ax/20dYXaieJRTuYMBL8ZGSC9YTpcqAzRMmNAAvvZGcK8N WcDADyAEJmaNF3zoBjexM7bhZI0qq25QdWutll7Oblk/7KUWB75Sn601qZpgzmsrIe SM/1Xuu7c8IFR2KWDzC0kf9ksRzBB4BKTd+LEUP/wCIlClskZoORmye9PRtIxA1rzQ Q4oOwYS5mPDjw== From: Jarkko Sakkinen To: linux-sgx@vger.kernel.org Cc: Nathaniel McCallum , Reinette Chatre , Jarkko Sakkinen , Dave Hansen , Thomas Gleixner , Ingo Molnar , Borislav Petkov , x86@kernel.org (maintainer:X86 ARCHITECTURE (32-BIT AND 64-BIT)), "H. Peter Anvin" , linux-kernel@vger.kernel.org (open list:X86 ARCHITECTURE (32-BIT AND 64-BIT)) Subject: [RFC PATCH v2.1 12/30] x86/sgx: Create utility to validate user provided offset and length Date: Fri, 4 Mar 2022 11:35:06 +0200 Message-Id: <20220304093524.397485-12-jarkko@kernel.org> X-Mailer: git-send-email 2.35.1 In-Reply-To: <20220304093524.397485-1-jarkko@kernel.org> References: <20220304093524.397485-1-jarkko@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-sgx@vger.kernel.org From: Reinette Chatre User provided offset and length is validated when parsing the parameters of the SGX_IOC_ENCLAVE_ADD_PAGES ioctl(). Extract this validation into a utility that can be used by the SGX2 ioctl()s that will also provide these values. Signed-off-by: Reinette Chatre --- arch/x86/kernel/cpu/sgx/ioctl.c | 28 ++++++++++++++++++++++------ 1 file changed, 22 insertions(+), 6 deletions(-) diff --git a/arch/x86/kernel/cpu/sgx/ioctl.c b/arch/x86/kernel/cpu/sgx/ioctl.c index 83df20e3e633..f487549bccba 100644 --- a/arch/x86/kernel/cpu/sgx/ioctl.c +++ b/arch/x86/kernel/cpu/sgx/ioctl.c @@ -372,6 +372,26 @@ static int sgx_encl_add_page(struct sgx_encl *encl, unsigned long src, return ret; } +/* + * Ensure user provided offset and length values are valid for + * an enclave. + */ +static int sgx_validate_offset_length(struct sgx_encl *encl, + unsigned long offset, + unsigned long length) +{ + if (!IS_ALIGNED(offset, PAGE_SIZE)) + return -EINVAL; + + if (!length || length & (PAGE_SIZE - 1)) + return -EINVAL; + + if (offset + length - PAGE_SIZE >= encl->size) + return -EINVAL; + + return 0; +} + /** * sgx_ioc_enclave_add_pages() - The handler for %SGX_IOC_ENCLAVE_ADD_PAGES * @encl: an enclave pointer @@ -425,14 +445,10 @@ static long sgx_ioc_enclave_add_pages(struct sgx_encl *encl, void __user *arg) if (copy_from_user(&add_arg, arg, sizeof(add_arg))) return -EFAULT; - if (!IS_ALIGNED(add_arg.offset, PAGE_SIZE) || - !IS_ALIGNED(add_arg.src, PAGE_SIZE)) - return -EINVAL; - - if (!add_arg.length || add_arg.length & (PAGE_SIZE - 1)) + if (!IS_ALIGNED(add_arg.src, PAGE_SIZE)) return -EINVAL; - if (add_arg.offset + add_arg.length - PAGE_SIZE >= encl->size) + if (sgx_validate_offset_length(encl, add_arg.offset, add_arg.length)) return -EINVAL; if (copy_from_user(&secinfo, (void __user *)add_arg.secinfo,