From patchwork Tue Feb 8 00:45:50 2022 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Reinette Chatre X-Patchwork-Id: 12738006 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 694DEC433F5 for ; Tue, 8 Feb 2022 01:07:14 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S240964AbiBHBHN (ORCPT ); Mon, 7 Feb 2022 20:07:13 -0500 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:59466 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1344220AbiBHAqR (ORCPT ); Mon, 7 Feb 2022 19:46:17 -0500 Received: from mga18.intel.com (mga18.intel.com [134.134.136.126]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 5BA7BC0612A4; Mon, 7 Feb 2022 16:46:16 -0800 (PST) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/simple; d=intel.com; i=@intel.com; q=dns/txt; s=Intel; t=1644281176; x=1675817176; h=from:to:cc:subject:date:message-id:in-reply-to: references:mime-version:content-transfer-encoding; bh=M+2L++RxeQbWVpCBPEiJ91GOEuKMdiIfqq5NEpf476Y=; b=RdggwiEHQwVakfdMA4mcRn5TvnjRhgBJ45i59zXuXENnqDljXVEN1TKk 8CYeI89+eY3smr5RqzWtViqNj2/pwAWuDAA+HxtenzjreeoUPowVvyCUO 41/CtPcYqr8cbvWbTkI4ZBOC2ibOXSustVg5WonQ1uDG0dJ2leBZCB+VY qyWaUFFIWORMRqDNhgk7XyS/sZMKY3gwNtxjgrnNocU5N3nYrsnquVDw8 3uxthjntRde/V7QLFJFYDaipUxC3FCMGLiT+uG/kNbAGNPCUj7YVUXCLB 9/vlLhIrhSntpFYCMesqcQRWD9UwMUFJZP+qtlFkyf3X0YwdXK5Lj2wao Q==; X-IronPort-AV: E=McAfee;i="6200,9189,10251"; a="232407993" X-IronPort-AV: E=Sophos;i="5.88,351,1635231600"; d="scan'208";a="232407993" Received: from orsmga002.jf.intel.com ([10.7.209.21]) by orsmga106.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 07 Feb 2022 16:46:10 -0800 X-IronPort-AV: E=Sophos;i="5.88,351,1635231600"; d="scan'208";a="499389554" Received: from rchatre-ws.ostc.intel.com ([10.54.69.144]) by orsmga002-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 07 Feb 2022 16:46:09 -0800 From: Reinette Chatre To: dave.hansen@linux.intel.com, jarkko@kernel.org, tglx@linutronix.de, bp@alien8.de, luto@kernel.org, mingo@redhat.com, linux-sgx@vger.kernel.org, x86@kernel.org Cc: seanjc@google.com, kai.huang@intel.com, cathy.zhang@intel.com, cedric.xing@intel.com, haitao.huang@intel.com, mark.shanahan@intel.com, hpa@zytor.com, linux-kernel@vger.kernel.org Subject: [PATCH V2 28/32] selftests/sgx: Test faulty enclave behavior Date: Mon, 7 Feb 2022 16:45:50 -0800 Message-Id: <640db753d78eed8146523d386fbf6c95e46ea4f4.1644274683.git.reinette.chatre@intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: References: MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-sgx@vger.kernel.org Removing a page from an initialized enclave involves three steps: first the user requests changing the page type to SGX_PAGE_TYPE_TRIM via an ioctl(), on success the ENCLU[EACCEPT] instruction needs to be run from within the enclave to accept the page removal, finally the user requests page removal to be completed via an ioctl(). Only after acceptance (ENCLU[EACCEPT]) from within the enclave can the kernel remove the page from a running enclave. Test the behavior when the user's request to change the page type succeeds, but the ENCLU[EACCEPT] instruction is not run before the ioctl() requesting page removal is run. This should not be permitted. Signed-off-by: Reinette Chatre --- Changes since V1: - Update to support ioctl() name change (SGX_IOC_PAGE_MODT -> SGX_IOC_ENCLAVE_MODIFY_TYPE) and provide secinfo as parameter instead of just page type (Jarkko). - Update test to reflect page removal ioctl() and struct name change: SGX_IOC_PAGE_REMOVE->SGX_IOC_ENCLAVE_REMOVE_PAGES, struct sgx_page_remove -> struct sgx_enclave_remove_pages (Jarkko). - Use ioctl() instead of ioctl in text (Dave). tools/testing/selftests/sgx/main.c | 116 +++++++++++++++++++++++++++++ 1 file changed, 116 insertions(+) diff --git a/tools/testing/selftests/sgx/main.c b/tools/testing/selftests/sgx/main.c index 53a581bd56c5..e9513ced1853 100644 --- a/tools/testing/selftests/sgx/main.c +++ b/tools/testing/selftests/sgx/main.c @@ -1472,4 +1472,120 @@ TEST_F(enclave, tcs_create) munmap(addr, 3 * PAGE_SIZE); } +/* + * Ensure sane behavior if user requests page removal, does not run + * EACCEPT from within enclave but still attempts to finalize page removal + * with the SGX_IOC_ENCLAVE_REMOVE_PAGES ioctl(). The latter should fail + * because the removal was not EACCEPTed from within the enclave. + */ +TEST_F(enclave, remove_added_page_no_eaccept) +{ + struct sgx_enclave_remove_pages remove_ioc; + struct encl_op_get_from_addr get_addr_op; + struct encl_op_put_to_addr put_addr_op; + struct sgx_enclave_modt modt_ioc; + struct sgx_secinfo secinfo; + unsigned long data_start; + int ret, errno_save; + + ASSERT_TRUE(setup_test_encl(ENCL_HEAP_SIZE_DEFAULT, &self->encl, _metadata)); + + memset(&self->run, 0, sizeof(self->run)); + self->run.tcs = self->encl.encl_base; + + /* + * Hardware (SGX2) and kernel support is needed for this test. Start + * with check that test has a chance of succeeding. + */ + memset(&modt_ioc, 0, sizeof(modt_ioc)); + ret = ioctl(self->encl.fd, SGX_IOC_ENCLAVE_MODIFY_TYPE, &modt_ioc); + + if (ret == -1) { + if (errno == ENOTTY) + SKIP(return, "Kernel does not support SGX_IOC_ENCLAVE_MODIFY_TYPE ioctl()"); + else if (errno == ENODEV) + SKIP(return, "System does not support SGX2"); + } + + /* + * Invalid parameters were provided during sanity check, + * expect command to fail. + */ + EXPECT_EQ(ret, -1); + + /* + * Page that will be removed is the second data page in the .data + * segment. This forms part of the local encl_buffer within the + * enclave. + */ + data_start = self->encl.encl_base + + encl_get_data_offset(&self->encl) + PAGE_SIZE; + + /* + * Sanity check that page at @data_start is writable before + * removing it. + * + * Start by writing MAGIC to test page. + */ + put_addr_op.value = MAGIC; + put_addr_op.addr = data_start; + put_addr_op.header.type = ENCL_OP_PUT_TO_ADDRESS; + + EXPECT_EQ(ENCL_CALL(&put_addr_op, &self->run, true), 0); + + EXPECT_EEXIT(&self->run); + EXPECT_EQ(self->run.exception_vector, 0); + EXPECT_EQ(self->run.exception_error_code, 0); + EXPECT_EQ(self->run.exception_addr, 0); + + /* + * Read memory that was just written to, confirming that data + * previously written (MAGIC) is present. + */ + get_addr_op.value = 0; + get_addr_op.addr = data_start; + get_addr_op.header.type = ENCL_OP_GET_FROM_ADDRESS; + + EXPECT_EQ(ENCL_CALL(&get_addr_op, &self->run, true), 0); + + EXPECT_EQ(get_addr_op.value, MAGIC); + EXPECT_EEXIT(&self->run); + EXPECT_EQ(self->run.exception_vector, 0); + EXPECT_EQ(self->run.exception_error_code, 0); + EXPECT_EQ(self->run.exception_addr, 0); + + /* Start page removal by requesting change of page type to PT_TRIM */ + memset(&modt_ioc, 0, sizeof(modt_ioc)); + memset(&secinfo, 0, sizeof(secinfo)); + + secinfo.flags = SGX_PAGE_TYPE_TRIM << 8; + modt_ioc.offset = encl_get_data_offset(&self->encl) + PAGE_SIZE; + modt_ioc.length = PAGE_SIZE; + modt_ioc.secinfo = (unsigned long)&secinfo; + + ret = ioctl(self->encl.fd, SGX_IOC_ENCLAVE_MODIFY_TYPE, &modt_ioc); + errno_save = ret == -1 ? errno : 0; + + EXPECT_EQ(ret, 0); + EXPECT_EQ(errno_save, 0); + EXPECT_EQ(modt_ioc.result, 0); + EXPECT_EQ(modt_ioc.count, 4096); + + /* Skip EACCEPT */ + + /* Send final ioctl() to complete page removal */ + memset(&remove_ioc, 0, sizeof(remove_ioc)); + + remove_ioc.offset = encl_get_data_offset(&self->encl) + PAGE_SIZE; + remove_ioc.length = PAGE_SIZE; + + ret = ioctl(self->encl.fd, SGX_IOC_ENCLAVE_REMOVE_PAGES, &remove_ioc); + errno_save = ret == -1 ? errno : 0; + + /* Operation not permitted since EACCEPT was omitted. */ + EXPECT_EQ(ret, -1); + EXPECT_EQ(errno_save, EPERM); + EXPECT_EQ(remove_ioc.count, 0); +} + TEST_HARNESS_MAIN