From patchwork Mon Jun 21 19:05:56 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Dave Hansen X-Patchwork-Id: 12335517 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=-8.8 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_PATCH,MAILING_LIST_MULTI,SPF_HELO_NONE, SPF_PASS autolearn=unavailable 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 E9548C4743C for ; Mon, 21 Jun 2021 19:06:41 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id CE76261289 for ; Mon, 21 Jun 2021 19:06:41 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230165AbhFUTIw (ORCPT ); Mon, 21 Jun 2021 15:08:52 -0400 Received: from mga17.intel.com ([192.55.52.151]:60414 "EHLO mga17.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S229897AbhFUTIw (ORCPT ); Mon, 21 Jun 2021 15:08:52 -0400 IronPort-SDR: cXHMRXQz4mGFt8clh0K/+U60tuEvJGnG9o8q3y2PDpQeeAg/J21wpyRflPDzQwN1gIFu7q8Bjq gvhORtvMmfcg== X-IronPort-AV: E=McAfee;i="6200,9189,10022"; a="187293641" X-IronPort-AV: E=Sophos;i="5.83,289,1616482800"; d="scan'208";a="187293641" Received: from orsmga006.jf.intel.com ([10.7.209.51]) by fmsmga107.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 21 Jun 2021 12:06:37 -0700 IronPort-SDR: z75lA64KpVlDa81rKjUVEAaNoYT9JJwKTUEy4mZGDOJKS4BvtY3G4Ps0S59j1/vwGbGelPPs2N 16KUGjrgClIw== X-ExtLoop1: 1 X-IronPort-AV: E=Sophos;i="5.83,289,1616482800"; d="scan'208";a="405721024" Received: from viggo.jf.intel.com (HELO localhost.localdomain) ([10.54.77.144]) by orsmga006.jf.intel.com with ESMTP; 21 Jun 2021 12:06:36 -0700 Subject: [PATCH] selftests/sgx: remove checks for file execute permissions To: linux-mm@kvack.org Cc: linux-kernel@vger.kernel.org, Dave Hansen , tim.gardner@canonical.com, jarkko@kernel.org, reinette.chatre@intel.com, shuah@kernel.org, linux-sgx@vger.kernel.org, linux-kselftest@vger.kernel.org From: Dave Hansen Date: Mon, 21 Jun 2021 12:05:56 -0700 Message-Id: <20210621190556.4B5DCBB1@viggo.jf.intel.com> Precedence: bulk List-ID: X-Mailing-List: linux-sgx@vger.kernel.org The SGX selftests can fail for a bunch of non-obvious reasons like 'noexec' permissions on /dev (which is the default *EVERYWHERE* it seems). A new test mistakenly also looked for +x permission on the /dev/sgx_enclave. File execute permissions really only apply to the ability of execve() to work on a file, *NOT* on the ability for an application to map the file with PROT_EXEC. SGX needs to mmap(PROT_EXEC), but doesn't need to execve() the device file. Remove the check. Fixes: 4284f7acb78b ("selftests/sgx: Improve error detection and messages") Reported-by: Tim Gardner Cc: Jarkko Sakkinen Cc: Reinette Chatre Cc: Dave Hansen Cc: Shuah Khan Cc: linux-sgx@vger.kernel.org Cc: linux-kselftest@vger.kernel.org Cc: linux-kernel@vger.kernel.org Tested-by: Reinette Chatre Signed-off-by: Dave Hansen Reviewed-by: Jarkko Sakkinen --- b/tools/testing/selftests/sgx/load.c | 16 +++------------- 1 file changed, 3 insertions(+), 13 deletions(-) diff -puN tools/testing/selftests/sgx/load.c~sgx-no-file-exec tools/testing/selftests/sgx/load.c --- a/tools/testing/selftests/sgx/load.c~sgx-no-file-exec 2021-06-21 11:48:25.226294281 -0700 +++ b/tools/testing/selftests/sgx/load.c 2021-06-21 12:03:28.023292029 -0700 @@ -150,16 +150,6 @@ bool encl_load(const char *path, struct goto err; } - /* - * This just checks if the /dev file has these permission - * bits set. It does not check that the current user is - * the owner or in the owning group. - */ - if (!(sb.st_mode & (S_IXUSR | S_IXGRP | S_IXOTH))) { - fprintf(stderr, "no execute permissions on device file %s\n", device_path); - goto err; - } - ptr = mmap(NULL, PAGE_SIZE, PROT_READ, MAP_SHARED, fd, 0); if (ptr == (void *)-1) { perror("mmap for read"); @@ -169,13 +159,13 @@ bool encl_load(const char *path, struct #define ERR_MSG \ "mmap() succeeded for PROT_READ, but failed for PROT_EXEC.\n" \ -" Check that current user has execute permissions on %s and \n" \ -" that /dev does not have noexec set: mount | grep \"/dev .*noexec\"\n" \ +" Check that /dev does not have noexec set:\n" \ +" \tmount | grep \"/dev .*noexec\"\n" \ " If so, remount it executable: mount -o remount,exec /dev\n\n" ptr = mmap(NULL, PAGE_SIZE, PROT_EXEC, MAP_SHARED, fd, 0); if (ptr == (void *)-1) { - fprintf(stderr, ERR_MSG, device_path); + fprintf(stderr, ERR_MSG); goto err; } munmap(ptr, PAGE_SIZE);