From patchwork Mon May 17 02:31:54 2021 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Moritz Fischer X-Patchwork-Id: 12260787 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=-17.0 required=3.0 tests=BAYES_00,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 CB2AAC433B4 for ; Mon, 17 May 2021 02:32:57 +0000 (UTC) Received: from vger.kernel.org (vger.kernel.org [23.128.96.18]) by mail.kernel.org (Postfix) with ESMTP id AAE08611CB for ; Mon, 17 May 2021 02:32:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S233096AbhEQCeM (ORCPT ); Sun, 16 May 2021 22:34:12 -0400 Received: from mail-pf1-f174.google.com ([209.85.210.174]:43952 "EHLO mail-pf1-f174.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230104AbhEQCeJ (ORCPT ); Sun, 16 May 2021 22:34:09 -0400 Received: by mail-pf1-f174.google.com with SMTP id d78so3080400pfd.10 for ; Sun, 16 May 2021 19:32:54 -0700 (PDT) X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20161025; h=x-gm-message-state:from:to:cc:subject:date:message-id:in-reply-to :references:mime-version:content-transfer-encoding; bh=mIuyThC8N8Vs45tWKR2XaYfdwdhs1NWGJ6K0ZJ36n20=; b=JP1aAEcAQX842C82FEn6j4Am2SSwbTWVjOVhRDXI11bV26sPJhOLYux6p7QlTJdmta dFNY6+uvYwaeNJMayNdvDkN55TWGUxzQj5uidb5r7izu1oPHqli8OeyOOnUwp8YLF67b /TIEr4j+jqyFhrZ+M87xmtSewl80Pplrq8iq+imYO8fQa+DJv4CVpYWpSpm3PHMAORmy 03QqFJqvw83sDvOTY+/DoUZI43k/mMn+hmp3WHsfKVykG3+SejSPhBhlkPV77VCn9iuo zPB0lTxVSvbPvNhpmZJmQsHQFj8xNfppPXQuGSaKL0pNnvTyVuDiN3UPImk2DcY+CSyp Zb6A== X-Gm-Message-State: AOAM533NuKDASmxBZH+kldlCbcL96JbtBtr6BoZ3Qt8H67PqNg35MO29 YNltJJWAK8FhBmRIZ0i8rL8= X-Google-Smtp-Source: ABdhPJzlcFmRO8+EzxYq2eb6Qfc2AVu7uw9AGVlHZL8BpL9JUdS7WlSQh5DMOQMOwiX4Mfhoh/ox0A== X-Received: by 2002:a63:581c:: with SMTP id m28mr22453421pgb.353.1621218774250; Sun, 16 May 2021 19:32:54 -0700 (PDT) Received: from localhost ([2601:647:5b00:1161:a4cc:eef9:fbc0:2781]) by smtp.gmail.com with ESMTPSA id x27sm9050892pfo.216.2021.05.16.19.32.53 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Sun, 16 May 2021 19:32:53 -0700 (PDT) From: Moritz Fischer To: gregkh@linuxfoundation.org Cc: linux-fpga@vger.kernel.org, moritzf@google.com, Moritz Fischer , Russ Weight , Tom Rix Subject: [PATCH 06/12] fpga: sec-mgr: enable cancel of secure update Date: Sun, 16 May 2021 19:31:54 -0700 Message-Id: <20210517023200.52707-7-mdf@kernel.org> X-Mailer: git-send-email 2.31.1 In-Reply-To: <20210517023200.52707-1-mdf@kernel.org> References: <20210517023200.52707-1-mdf@kernel.org> MIME-Version: 1.0 Precedence: bulk List-ID: X-Mailing-List: linux-fpga@vger.kernel.org From: Russ Weight 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 Signed-off-by: Moritz Fischer --- .../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 c5d0b9d7c7e4..749f2d4c78d3 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: June 2021 +KernelVersion: 5.14 +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: June 2021 KernelVersion: 5.14 diff --git a/drivers/fpga/fpga-sec-mgr.c b/drivers/fpga/fpga-sec-mgr.c index bc6b35cc7237..48950843c2b4 100644 --- a/drivers/fpga/fpga-sec-mgr.c +++ b/drivers/fpga/fpga-sec-mgr.c @@ -43,6 +43,23 @@ 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) { + fpga_sec_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); @@ -74,15 +91,19 @@ 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); - while (smgr->remaining_size) { + if (progress_transition(smgr, FPGA_SEC_PROG_WRITING)) + goto done; + + while (smgr->remaining_size && !smgr->request_cancel) { ret = smgr->sops->write_blk(smgr, offset); if (ret != FPGA_SEC_ERR_NONE) { fpga_sec_dev_error(smgr, ret); @@ -92,7 +113,9 @@ static void fpga_sec_mgr_update(struct work_struct *work) offset = fw->size - smgr->remaining_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); @@ -229,6 +252,7 @@ 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); @@ -239,8 +263,32 @@ 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, @@ -464,6 +512,9 @@ 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 6b7b8a3d6aac..0e1f50434024 100644 --- a/include/linux/fpga/fpga-sec-mgr.h +++ b/include/linux/fpga/fpga-sec-mgr.h @@ -72,6 +72,7 @@ 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; };