From patchwork Wed Dec 9 23:44:00 2020 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Russ Weight X-Patchwork-Id: 11962879 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=-16.7 required=3.0 tests=BAYES_00, HEADER_FROM_DIFFERENT_DOMAINS,INCLUDES_CR_TRAILER,INCLUDES_PATCH, MAILING_LIST_MULTI,SPF_HELO_NONE,SPF_PASS,URIBL_BLOCKED,USER_AGENT_GIT 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 BEAB6C4361B for ; Wed, 9 Dec 2020 23:46:18 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id 87F7C23B77 for ; Wed, 9 Dec 2020 23:46:18 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S2388927AbgLIXpf (ORCPT ); Wed, 9 Dec 2020 18:45:35 -0500 Received: from mga05.intel.com ([192.55.52.43]:64561 "EHLO mga05.intel.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1731022AbgLIXp3 (ORCPT ); Wed, 9 Dec 2020 18:45:29 -0500 IronPort-SDR: XXzkuodhqikqsC95E3xTkJyIB2LASh3UiRMshXzwGVAOpEIdGgxK6TuEkEOKu+4qMfd/WVBSiA ph089aKJH6SQ== X-IronPort-AV: E=McAfee;i="6000,8403,9830"; a="258884341" X-IronPort-AV: E=Sophos;i="5.78,407,1599548400"; d="scan'208";a="258884341" Received: from orsmga003.jf.intel.com ([10.7.209.27]) by fmsmga105.fm.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 09 Dec 2020 15:44:08 -0800 IronPort-SDR: B8fAm8XQfL3gEdiMdn3vouJKuIH9GYYmTbFmqa0/3lOcZw44EUCJ1x4UXXhZakmEvWEHS09PvA dR0TTvt4VehQ== X-IronPort-AV: E=Sophos;i="5.78,407,1599548400"; d="scan'208";a="333100040" Received: from rhweight-mobl2.amr.corp.intel.com (HELO rhweight-mobl2.ra.intel.com) ([10.255.229.49]) by orsmga003-auth.jf.intel.com with ESMTP/TLS/ECDHE-RSA-AES256-GCM-SHA384; 09 Dec 2020 15:44:07 -0800 From: Russ Weight To: mdf@kernel.org, linux-fpga@vger.kernel.org, linux-kernel@vger.kernel.org Cc: trix@redhat.com, lgoncalv@redhat.com, yilun.xu@intel.com, hao.wu@intel.com, matthew.gerlach@intel.com, Russ Weight Subject: [PATCH v8 6/7] fpga: sec-mgr: enable cancel of secure update Date: Wed, 9 Dec 2020 15:44:00 -0800 Message-Id: <20201209234401.78668-7-russell.h.weight@intel.com> X-Mailer: git-send-email 2.25.1 In-Reply-To: <20201209234401.78668-1-russell.h.weight@intel.com> References: <20201209234401.78668-1-russell.h.weight@intel.com> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-fpga@vger.kernel.org Extend the FPGA Security Manager class driver to include an update/cancel sysfs file that can be written to request that an update be canceled. The write may return EBUSY if the update has progressed to the point that it cannot be canceled by software or ENODEV if there is no update in progress. Signed-off-by: Russ Weight Reviewed-by: Tom Rix --- v8: - No change v7: - Changed Date in documentation file to December 2020 v6: - No change v5: - No change v4: - Changed from "Intel FPGA Security Manager" to FPGA Security Manager" and removed unnecessary references to "Intel". - Changed: iops -> sops, imgr -> smgr, IFPGA_ -> FPGA_, ifpga_ to fpga_ v3: - No change v2: - Bumped documentation date and version - Minor code cleanup per review comments --- .../ABI/testing/sysfs-class-fpga-sec-mgr | 10 ++++ drivers/fpga/fpga-sec-mgr.c | 59 +++++++++++++++++-- include/linux/fpga/fpga-sec-mgr.h | 1 + 3 files changed, 66 insertions(+), 4 deletions(-) diff --git a/Documentation/ABI/testing/sysfs-class-fpga-sec-mgr b/Documentation/ABI/testing/sysfs-class-fpga-sec-mgr index 62dc04e4335d..96694f229aff 100644 --- a/Documentation/ABI/testing/sysfs-class-fpga-sec-mgr +++ b/Documentation/ABI/testing/sysfs-class-fpga-sec-mgr @@ -17,6 +17,16 @@ Description: Write only. Write the filename of an image and Root Entry Hashes, and to cancel Code Signing Keys (CSK). +What: /sys/class/fpga_sec_mgr/fpga_secX/update/cancel +Date: December 2020 +KernelVersion: 5.11 +Contact: Russ Weight +Description: Write-only. Write a "1" to this file to request + that a current update be canceled. This request + will be rejected (EBUSY) if the programming phase + has already started or (ENODEV) if there is no + update in progress. + What: /sys/class/fpga_sec_mgr/fpga_secX/update/status Date: December 2020 KernelVersion: 5.11 diff --git a/drivers/fpga/fpga-sec-mgr.c b/drivers/fpga/fpga-sec-mgr.c index 951020942991..d354fe2ab582 100644 --- a/drivers/fpga/fpga-sec-mgr.c +++ b/drivers/fpga/fpga-sec-mgr.c @@ -45,6 +45,23 @@ static void fpga_sec_dev_error(struct fpga_sec_mgr *smgr, smgr->sops->cancel(smgr); } +static int progress_transition(struct fpga_sec_mgr *smgr, + enum fpga_sec_prog new_progress) +{ + int ret = 0; + + mutex_lock(&smgr->lock); + if (smgr->request_cancel) { + set_error(smgr, FPGA_SEC_ERR_CANCELED); + smgr->sops->cancel(smgr); + ret = -ECANCELED; + } else { + update_progress(smgr, new_progress); + } + mutex_unlock(&smgr->lock); + return ret; +} + static void progress_complete(struct fpga_sec_mgr *smgr) { mutex_lock(&smgr->lock); @@ -76,16 +93,20 @@ static void fpga_sec_mgr_update(struct work_struct *work) goto release_fw_exit; } - update_progress(smgr, FPGA_SEC_PROG_PREPARING); + if (progress_transition(smgr, FPGA_SEC_PROG_PREPARING)) + goto modput_exit; + ret = smgr->sops->prepare(smgr); if (ret != FPGA_SEC_ERR_NONE) { fpga_sec_dev_error(smgr, ret); goto modput_exit; } - update_progress(smgr, FPGA_SEC_PROG_WRITING); + if (progress_transition(smgr, FPGA_SEC_PROG_WRITING)) + goto done; + size = smgr->remaining_size; - while (size) { + while (size && !smgr->request_cancel) { blk_size = min_t(u32, size, WRITE_BLOCK_SIZE); size -= blk_size; ret = smgr->sops->write_blk(smgr, offset, blk_size); @@ -98,7 +119,9 @@ static void fpga_sec_mgr_update(struct work_struct *work) offset += blk_size; } - update_progress(smgr, FPGA_SEC_PROG_PROGRAMMING); + if (progress_transition(smgr, FPGA_SEC_PROG_PROGRAMMING)) + goto done; + ret = smgr->sops->poll_complete(smgr); if (ret != FPGA_SEC_ERR_NONE) fpga_sec_dev_error(smgr, ret); @@ -235,6 +258,7 @@ static ssize_t filename_store(struct device *dev, struct device_attribute *attr, } smgr->err_code = FPGA_SEC_ERR_NONE; + smgr->request_cancel = false; smgr->progress = FPGA_SEC_PROG_READING; reinit_completion(&smgr->update_done); schedule_work(&smgr->work); @@ -245,8 +269,32 @@ static ssize_t filename_store(struct device *dev, struct device_attribute *attr, } static DEVICE_ATTR_WO(filename); +static ssize_t cancel_store(struct device *dev, struct device_attribute *attr, + const char *buf, size_t count) +{ + struct fpga_sec_mgr *smgr = to_sec_mgr(dev); + bool cancel; + int ret = count; + + if (kstrtobool(buf, &cancel) || !cancel) + return -EINVAL; + + mutex_lock(&smgr->lock); + if (smgr->progress == FPGA_SEC_PROG_PROGRAMMING) + ret = -EBUSY; + else if (smgr->progress == FPGA_SEC_PROG_IDLE) + ret = -ENODEV; + else + smgr->request_cancel = true; + mutex_unlock(&smgr->lock); + + return ret; +} +static DEVICE_ATTR_WO(cancel); + static struct attribute *sec_mgr_update_attrs[] = { &dev_attr_filename.attr, + &dev_attr_cancel.attr, &dev_attr_status.attr, &dev_attr_error.attr, &dev_attr_remaining_size.attr, @@ -468,6 +516,9 @@ void fpga_sec_mgr_unregister(struct fpga_sec_mgr *smgr) goto unregister; } + if (smgr->progress != FPGA_SEC_PROG_PROGRAMMING) + smgr->request_cancel = true; + mutex_unlock(&smgr->lock); wait_for_completion(&smgr->update_done); diff --git a/include/linux/fpga/fpga-sec-mgr.h b/include/linux/fpga/fpga-sec-mgr.h index 78f8dc51a508..e63e6437f394 100644 --- a/include/linux/fpga/fpga-sec-mgr.h +++ b/include/linux/fpga/fpga-sec-mgr.h @@ -73,6 +73,7 @@ struct fpga_sec_mgr { enum fpga_sec_prog progress; enum fpga_sec_prog err_state; /* progress state at time of failure */ enum fpga_sec_err err_code; /* security manager error code */ + bool request_cancel; bool driver_unload; void *priv; };