Message ID | 20230519201300.12964-6-jorge.lopez2@hp.com |
---|---|
State | New |
Headers |
Return-Path: <linux-kernel-owner@vger.kernel.org> Delivered-To: ouuuleilei@gmail.com Received: by 2002:a59:b0ea:0:b0:3b6:4342:cba0 with SMTP id b10csp1499036vqo; Fri, 19 May 2023 13:24:32 -0700 (PDT) X-Google-Smtp-Source: ACHHUZ7mVFLSp4O3+2CNOcEVlXHM86bigaZmhdTDgdoORt+Jrodi9LfVTc4e5vFRdEr7KSwY3zmb X-Received: by 2002:a05:6a00:1a15:b0:646:5041:9729 with SMTP id g21-20020a056a001a1500b0064650419729mr4678048pfv.0.1684527872342; Fri, 19 May 2023 13:24:32 -0700 (PDT) ARC-Seal: i=1; a=rsa-sha256; t=1684527872; cv=none; d=google.com; s=arc-20160816; b=yJI58KXbTRuf2TigwMEpNutBQhQuQyKPD3TyPf5cFtvGLTHh4pNFzz5BIkn+FP1qAD BuBadW4xja7sIqCJP8/epcPCPGXKlJB1NIS6aDoJhVLbh5ZBhuVEO6zwjSht6+tLmPjw 8Awj8Ht01XCOj4xFvlSIrCT05rGJN9Fu18619QUeJMiDWVQJ6XHlftMFV8L7vF4mOuX8 0rYV4GboOqwQPTBQEJjN65rM3iaVMhKYWdgcTWKpAPp03GqWfMdnsx9cr7+d335v2e/H Onoa7eCPKF1gd91g5rc2q+8YCEevZOI+CGVQeN79G8W09xowg7RRF5OA/BgyTnnWiEh9 ZYEQ== ARC-Message-Signature: i=1; a=rsa-sha256; c=relaxed/relaxed; d=google.com; s=arc-20160816; h=list-id:precedence:content-transfer-encoding:mime-version :references:in-reply-to:message-id:date:subject:to:from :dkim-signature; bh=dkmqTOnqH10zqck+vlU1cotzouf6/Ip6L8zG46cMmoY=; b=Fdm8kB1jdMyl4Y07YsohrbPxLtWq7GkqhDmFKDLMoAE2n9z1mhPhGrSO5HIV2SN4lu MnAVpiVAWSeYqMSccKlk21IeSOgOqQp4kF6K8TAzq8olaLOD2Ip0k6w8VI0kxBf0vCSR G5e6bORM2PNJJDIh2BbNrPSCPK2D2OTfnf7ErkLNuJdHJKCgWwRynuXrtOBGJpe0Q4Ht FOT8HOxVuLAB1SE5b+trfvlhHk7D5ElJKBeWFM10IxFMr+g56o/GoKFOFzP03eHWn920 L52iASUxmIZU6tQXxQj5R076exXnX+MBDW5kWg2MnmAnFobz3jJAQes28nTUZuSsBr1e Qn9Q== ARC-Authentication-Results: i=1; mx.google.com; dkim=pass header.i=@gmail.com header.s=20221208 header.b=mIjWWily; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com Received: from out1.vger.email (out1.vger.email. [2620:137:e000::1:20]) by mx.google.com with ESMTP id p67-20020a625b46000000b0064cce871b49si168097pfb.137.2023.05.19.13.24.20; Fri, 19 May 2023 13:24:32 -0700 (PDT) Received-SPF: pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) client-ip=2620:137:e000::1:20; Authentication-Results: mx.google.com; dkim=pass header.i=@gmail.com header.s=20221208 header.b=mIjWWily; spf=pass (google.com: domain of linux-kernel-owner@vger.kernel.org designates 2620:137:e000::1:20 as permitted sender) smtp.mailfrom=linux-kernel-owner@vger.kernel.org; dmarc=pass (p=NONE sp=QUARANTINE dis=NONE) header.from=gmail.com Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S230409AbjESUN0 (ORCPT <rfc822;wlfightup@gmail.com> + 99 others); Fri, 19 May 2023 16:13:26 -0400 Received: from lindbergh.monkeyblade.net ([23.128.96.19]:50374 "EHLO lindbergh.monkeyblade.net" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S230016AbjESUNT (ORCPT <rfc822;linux-kernel@vger.kernel.org>); Fri, 19 May 2023 16:13:19 -0400 Received: from mail-ot1-x336.google.com (mail-ot1-x336.google.com [IPv6:2607:f8b0:4864:20::336]) by lindbergh.monkeyblade.net (Postfix) with ESMTPS id 85F4CE47; Fri, 19 May 2023 13:13:08 -0700 (PDT) Received: by mail-ot1-x336.google.com with SMTP id 46e09a7af769-6ab087111faso1537135a34.3; Fri, 19 May 2023 13:13:08 -0700 (PDT) DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=gmail.com; s=20221208; t=1684527188; x=1687119188; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:to:from:from:to:cc:subject:date:message-id :reply-to; bh=dkmqTOnqH10zqck+vlU1cotzouf6/Ip6L8zG46cMmoY=; b=mIjWWilyhq1ANl/lQrvXS06gM/4v0pCFy6dE4bD0PfhBpiVgOKk11p1ql209KXeU80 Ak+XkwII6rI0lfNnAvY6y7AI3DimKge7dmD+Ou/OuhhC9GKBHrFPaWOMch4lr2kBXKNQ cIO5w9PKnx6vUoDU/tELsOvItFpngvbs5TEdSwm1H9YqRzXuB5TsRjF607Qlb9Gdk0YS eiVnmh3YkHUUylvTSjXkDqj94B3g/KNRMi20HbZxoNc1mAxzy1ez4n/YWgFjaK1Elime JqBAVT1O/FKLFCRgFU47XdcXZdHPUfGJ1KWB6qrXH/khzDSAPbNyanF370cdE8MuKypN 1TNw== X-Google-DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=1e100.net; s=20221208; t=1684527188; x=1687119188; h=content-transfer-encoding:mime-version:references:in-reply-to :message-id:date:subject:to:from:x-gm-message-state:from:to:cc :subject:date:message-id:reply-to; bh=dkmqTOnqH10zqck+vlU1cotzouf6/Ip6L8zG46cMmoY=; b=AGDqhpgtVurRiNTBDFrnuLMaoqBMkuXnr/S/knUv9jO8vXRObi8ungoEhSau2yQ4wO QnhbZ4PKpnE+n2p7CGh48gv84IYtYnZbSx9RvSC8x56LvraTw0FWqm01OKvEtfpCmI0R L/zFKgUL42R98dIwA9b/bxDIy6Ci9lUBtnWU17Ckcx0ImXzvqshY1YxlyJIF7k4Yq8pp 2Q3Mho+oYHGItQeZg2XX5iROMnhkUhTgBqBntxKJ69/U1NUXoE4VgLUv2ZdlX6LKPqrC HMGGvbG2Lx21zMzRci1fu/Z0fnKSvlj+T+P0sN61t0Jdf8iryuD53CilwA8cjN335FJx 5SJQ== X-Gm-Message-State: AC+VfDzLACQ4C8A3Evlf/DgL6/LlMgy7Y4vkNOUY8oVC/oMtD/b7niby cWr15I1h1r7OU8pxO71o0cU= X-Received: by 2002:a05:6871:6aa6:b0:196:5d33:953c with SMTP id zf38-20020a0568716aa600b001965d33953cmr1238794oab.9.1684527187591; Fri, 19 May 2023 13:13:07 -0700 (PDT) Received: from grumpy-VECTOR.hsd1.tx.comcast.net ([2601:2c3:480:7390:e6dc:4936:31b7:d3d0]) by smtp.gmail.com with ESMTPSA id g4-20020a056870d20400b001964dc3dadesm2325239oac.45.2023.05.19.13.13.06 (version=TLS1_3 cipher=TLS_AES_256_GCM_SHA384 bits=256/256); Fri, 19 May 2023 13:13:07 -0700 (PDT) From: Jorge Lopez <jorgealtxwork@gmail.com> X-Google-Original-From: Jorge Lopez <jorge.lopez2@hp.com> To: hdegoede@redhat.com, platform-driver-x86@vger.kernel.org, linux-kernel@vger.kernel.org, thomas@t-8ch.de, ilpo.jarvinen@linux.intel.com Subject: [PATCH v15 05/13] hp-bioscfg: enum-attributes Date: Fri, 19 May 2023 15:12:52 -0500 Message-Id: <20230519201300.12964-6-jorge.lopez2@hp.com> X-Mailer: git-send-email 2.34.1 In-Reply-To: <20230519201300.12964-1-jorge.lopez2@hp.com> References: <20230519201300.12964-1-jorge.lopez2@hp.com> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit X-Spam-Status: No, score=-2.1 required=5.0 tests=BAYES_00,DKIM_SIGNED, DKIM_VALID,DKIM_VALID_AU,DKIM_VALID_EF,FREEMAIL_FROM, RCVD_IN_DNSWL_NONE,SPF_HELO_NONE,SPF_PASS,T_SCC_BODY_TEXT_LINE autolearn=ham autolearn_force=no version=3.4.6 X-Spam-Checker-Version: SpamAssassin 3.4.6 (2021-04-09) on lindbergh.monkeyblade.net Precedence: bulk List-ID: <linux-kernel.vger.kernel.org> X-Mailing-List: linux-kernel@vger.kernel.org X-getmail-retrieved-from-mailbox: =?utf-8?q?INBOX?= X-GMAIL-THRID: =?utf-8?q?1766355498291938045?= X-GMAIL-MSGID: =?utf-8?q?1766355498291938045?= |
Series |
hp-bioscfg driver
|
|
Commit Message
Jorge Lopez
May 19, 2023, 8:12 p.m. UTC
HP BIOS Configuration driver purpose is to provide a driver supporting
the latest sysfs class firmware attributes framework allowing the user
to change BIOS settings and security solutions on HP Inc.’s commercial
notebooks.
Many features of HP Commercial notebooks can be managed using Windows
Management Instrumentation (WMI). WMI is an implementation of Web-Based
Enterprise Management (WBEM) that provides a standards-based interface
for changing and monitoring system settings. HP BIOSCFG driver provides
a native Linux solution and the exposed features facilitates the
migration to Linux environments.
The Linux security features to be provided in hp-bioscfg driver enables
managing the BIOS settings and security solutions via sysfs, a virtual
filesystem that can be used by user-mode applications. The new
documentation cover HP-specific firmware sysfs attributes such Secure
Platform Management and Sure Start. Each section provides security
feature description and identifies sysfs directories and files exposed
by the driver.
Many HP Commercial notebooks include a feature called Secure Platform
Management (SPM), which replaces older password-based BIOS settings
management with public key cryptography. PC secure product management
begins when a target system is provisioned with cryptographic keys
that are used to ensure the integrity of communications between system
management utilities and the BIOS.
HP Commercial notebooks have several BIOS settings that control its
behaviour and capabilities, many of which are related to security.
To prevent unauthorized changes to these settings, the system can
be configured to use a cryptographic signature-based authorization
string that the BIOS will use to verify authorization to modify the
setting.
Linux Security components are under development and not published yet.
The only linux component is the driver (hp bioscfg) at this time.
Other published security components are under Windows.
Signed-off-by: Jorge Lopez <jorge.lopez2@hp.com>
---
Based on the latest platform-drivers-x86.git/for-next
---
.../x86/hp/hp-bioscfg/enum-attributes.c | 465 ++++++++++++++++++
1 file changed, 465 insertions(+)
create mode 100644 drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c
Comments
On 2023-05-19 15:12:52-0500, Jorge Lopez wrote: <snip> > .../x86/hp/hp-bioscfg/enum-attributes.c | 465 ++++++++++++++++++ > 1 file changed, 465 insertions(+) > create mode 100644 drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c > > diff --git a/drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c b/drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c > new file mode 100644 > index 000000000000..80842835606d > --- /dev/null > +++ b/drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c > @@ -0,0 +1,465 @@ > +// SPDX-License-Identifier: GPL-2.0 > +/* > + * Functions corresponding to enumeration type attributes under > + * BIOS Enumeration GUID for use with hp-bioscfg driver. > + * > + * Copyright (c) 2022 HP Development Company, L.P. > + */ > + > +#include "bioscfg.h" > + > +GET_INSTANCE_ID(enumeration); > + > +static ssize_t current_value_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) > +{ > + int instance_id = get_enumeration_instance_id(kobj); > + > + if (instance_id < 0) > + return -EIO; > + > + return sysfs_emit(buf, "%s\n", > + bioscfg_drv.enumeration_data[instance_id].current_value); > +} > + > +/** > + * validate_enumeration_input() - > + * Validate input of current_value against possible values > + * > + * @instance_id: The instance on which input is validated > + * @buf: Input value > + */ > +static int validate_enumeration_input(int instance_id, const char *buf) > +{ > + int i; > + int found = 0; > + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; > + > + /* Is it a read only attribute */ > + if (enum_data->common.is_readonly) > + return -EIO; > + > + for (i = 0; i < enum_data->possible_values_size && !found; i++) > + if (!strcmp(enum_data->possible_values[i], buf)) > + found = 1; > + > + if (!found) > + return -EINVAL; > + > + return 0; > +} > + > +static void update_enumeration_value(int instance_id, char *attr_value) > +{ > + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; > + > + strscpy(enum_data->current_value, > + attr_value, > + sizeof(enum_data->current_value)); > +} > + > +ATTRIBUTE_S_COMMON_PROPERTY_SHOW(display_name, enumeration); > +static struct kobj_attribute enumeration_display_name = > + __ATTR_RO(display_name); > + > +ATTRIBUTE_PROPERTY_STORE(current_value, enumeration); > +static struct kobj_attribute enumeration_current_val = > + __ATTR_RW(current_value); > + > +ATTRIBUTE_VALUES_PROPERTY_SHOW(possible_values, enumeration, SEMICOLON_SEP); > +static struct kobj_attribute enumeration_poss_val = > + __ATTR_RO(possible_values); > + > +static ssize_t type_show(struct kobject *kobj, struct kobj_attribute *attr, > + char *buf) > +{ > + return sysfs_emit(buf, "enumeration\n"); > +} > + > +static struct kobj_attribute enumeration_type = > + __ATTR_RO(type); > + > +static struct kobj_attribute common_display_langcode = > + __ATTR_RO(display_name_language_code); > + > +static struct attribute *enumeration_attrs[] = { > + &common_display_langcode.attr, > + &enumeration_display_name.attr, > + &enumeration_current_val.attr, > + &enumeration_poss_val.attr, > + &enumeration_type.attr, > + NULL > +}; > + > +static const struct attribute_group enumeration_attr_group = { > + .attrs = enumeration_attrs, > +}; > + > +int hp_alloc_enumeration_data(void) > +{ > + bioscfg_drv.enumeration_instances_count = > + hp_get_instance_count(HP_WMI_BIOS_ENUMERATION_GUID); > + > + bioscfg_drv.enumeration_data = kcalloc(bioscfg_drv.enumeration_instances_count, > + sizeof(*bioscfg_drv.enumeration_data), GFP_KERNEL); > + if (!bioscfg_drv.enumeration_data) { > + bioscfg_drv.enumeration_instances_count = 0; > + return -ENOMEM; > + } > + return 0; > +} > + > +/* Expected Values types associated with each element */ > +static const acpi_object_type expected_enum_types[] = { > + [NAME] = ACPI_TYPE_STRING, > + [VALUE] = ACPI_TYPE_STRING, > + [PATH] = ACPI_TYPE_STRING, > + [IS_READONLY] = ACPI_TYPE_INTEGER, > + [DISPLAY_IN_UI] = ACPI_TYPE_INTEGER, > + [REQUIRES_PHYSICAL_PRESENCE] = ACPI_TYPE_INTEGER, > + [SEQUENCE] = ACPI_TYPE_INTEGER, > + [PREREQUISITES_SIZE] = ACPI_TYPE_INTEGER, > + [PREREQUISITES] = ACPI_TYPE_STRING, > + [SECURITY_LEVEL] = ACPI_TYPE_INTEGER, > + [ENUM_CURRENT_VALUE] = ACPI_TYPE_STRING, > + [ENUM_SIZE] = ACPI_TYPE_INTEGER, > + [ENUM_POSSIBLE_VALUES] = ACPI_TYPE_STRING, > +}; > + > +static int hp_populate_enumeration_elements_from_package(union acpi_object *enum_obj, > + int enum_obj_count, > + int instance_id) > +{ > + char *str_value = NULL; > + int value_len; > + u32 size = 0; > + u32 int_value; > + int elem = 0; > + int reqs; > + int pos_values; > + int ret; > + int eloc; > + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; > + > + for (elem = 1, eloc = 1; elem < enum_obj_count; elem++, eloc++) { > + /* ONLY look at the first ENUM_ELEM_CNT elements */ > + if (eloc == ENUM_ELEM_CNT) > + goto exit_enumeration_package; > + > + switch (enum_obj[elem].type) { > + case ACPI_TYPE_STRING: > + if (PREREQUISITES != elem && ENUM_POSSIBLE_VALUES != elem) { > + ret = hp_convert_hexstr_to_str(enum_obj[elem].string.pointer, > + enum_obj[elem].string.length, > + &str_value, &value_len); > + if (ret) > + return -EINVAL; > + } > + break; > + case ACPI_TYPE_INTEGER: > + int_value = (u32)enum_obj[elem].integer.value; > + break; > + default: > + pr_warn("Unsupported object type [%d]\n", enum_obj[elem].type); > + continue; > + } > + > + /* Check that both expected and read object type match */ > + if (expected_enum_types[eloc] != enum_obj[elem].type) { > + pr_err("Error expected type %d for elem %d, but got type %d instead\n", > + expected_enum_types[eloc], elem, enum_obj[elem].type); > + return -EIO; > + } > + > + /* Assign appropriate element value to corresponding field */ > + switch (eloc) { > + case NAME: > + case VALUE: > + break; > + case PATH: > + strscpy(enum_data->common.path, str_value, > + sizeof(enum_data->common.path)); > + break; > + case IS_READONLY: > + enum_data->common.is_readonly = int_value; > + break; > + case DISPLAY_IN_UI: > + enum_data->common.display_in_ui = int_value; > + break; > + case REQUIRES_PHYSICAL_PRESENCE: > + enum_data->common.requires_physical_presence = int_value; > + break; > + case SEQUENCE: > + enum_data->common.sequence = int_value; > + break; > + case PREREQUISITES_SIZE: > + enum_data->common.prerequisites_size = int_value; > + if (int_value > MAX_PREREQUISITES_SIZE) > + pr_warn("Prerequisites size value exceeded the maximum number of elements supported or data may be malformed\n"); > + > + /* > + * This HACK is needed to keep the expected > + * element list pointing to the right obj[elem].type > + * when the size is zero. PREREQUISITES > + * object is omitted by BIOS when the size is > + * zero. > + */ > + if (int_value == 0) > + eloc++; > + break; > + > + case PREREQUISITES: > + size = min_t(u32, enum_data->common.prerequisites_size, MAX_PREREQUISITES_SIZE); We cannot blindly truncate this to a maximum value. The firmware reported an amount of elements it would return. If this value is to big than we can not just intpret the data as if it was something the firmware did not return. An error needs to be reported to userspace. A default value is not enough as userspace can not interpret this properly. (Affects all attributes) > + for (reqs = 0; reqs < size; reqs++) { > + if (elem >= enum_obj_count) { > + pr_err("Error enum-objects package is too small\n"); > + return -EINVAL; > + } > + > + ret = hp_convert_hexstr_to_str(enum_obj[elem + reqs].string.pointer, > + enum_obj[elem + reqs].string.length, > + &str_value, &value_len); > + > + if (ret) > + return -EINVAL; > + > + strscpy(enum_data->common.prerequisites[reqs], > + str_value, > + sizeof(enum_data->common.prerequisites[reqs])); > + > + kfree(str_value); > + } > + break; > + > + case SECURITY_LEVEL: > + enum_data->common.security_level = int_value; > + break; > + > + case ENUM_CURRENT_VALUE: > + strscpy(enum_data->current_value, > + str_value, sizeof(enum_data->current_value)); > + break; > + case ENUM_SIZE: > + enum_data->possible_values_size = int_value; > + if (int_value > MAX_VALUES_SIZE) > + pr_warn("Possible number values size value exceeded the maximum number of elements supported or data may be malformed\n"); > + > + /* > + * This HACK is needed to keep the expected > + * element list pointing to the right obj[elem].type > + * when the size is zero. POSSIBLE_VALUES > + * object is omitted by BIOS when the size is zero. > + */ > + if (int_value == 0) > + eloc++; > + break; > + > + case ENUM_POSSIBLE_VALUES: > + size = enum_data->possible_values_size; > + > + for (pos_values = 0; pos_values < size && pos_values < MAX_VALUES_SIZE; > + pos_values++) { > + if (elem >= enum_obj_count) { > + pr_err("Error enum-objects package is too small\n"); > + return -EINVAL; > + } > + > + ret = hp_convert_hexstr_to_str(enum_obj[elem + pos_values].string.pointer, > + enum_obj[elem + pos_values].string.length, > + &str_value, &value_len); > + > + if (ret) > + return -EINVAL; > + > + /* > + * ignore strings when possible values size > + * is greater than MAX_VALUES_SIZE > + */ > + if (size < MAX_VALUES_SIZE) > + strscpy(enum_data->possible_values[pos_values], > + str_value, > + sizeof(enum_data->possible_values[pos_values])); > + } > + break; > + default: > + pr_warn("Invalid element: %d found in Enumeration attribute or data may be malformed\n", elem); > + break; > + } > + > + kfree(str_value); > + } > + > +exit_enumeration_package: > + kfree(str_value); > + return 0; > +} > + > +/** > + * hp_populate_enumeration_package_data() - > + * Populate all properties of an instance under enumeration attribute > + * > + * @enum_obj: ACPI object with enumeration data > + * @instance_id: The instance to enumerate > + * @attr_name_kobj: The parent kernel object > + */ > +int hp_populate_enumeration_package_data(union acpi_object *enum_obj, > + int instance_id, > + struct kobject *attr_name_kobj) > +{ > + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; > + > + enum_data->attr_name_kobj = attr_name_kobj; > + > + hp_populate_enumeration_elements_from_package(enum_obj, > + enum_obj->package.count, > + instance_id); > + hp_update_attribute_permissions(enum_data->common.is_readonly, > + &enumeration_current_val); > + /* > + * Several attributes have names such "MONDAY". Friendly > + * user nane is generated to make the name more descriptive > + */ > + hp_friendly_user_name_update(enum_data->common.path, > + attr_name_kobj->name, > + enum_data->common.display_name, > + sizeof(enum_data->common.display_name)); > + return sysfs_create_group(attr_name_kobj, &enumeration_attr_group); > +} > + > +static int hp_populate_enumeration_elements_from_buffer(u8 *buffer_ptr, u32 *buffer_size, > + int instance_id) > +{ > + int reqs; > + int values; > + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; > + > + /* > + * In earlier implementation, reported errors were ignored > + * causing the data to remain uninitialized. It is for this > + * reason functions may return an error and no validation > + * takes place. > + */ Where is this error returned? > + > + // VALUE: > + hp_get_string_from_buffer(&buffer_ptr, buffer_size, enum_data->current_value, > + sizeof(enum_data->current_value)); > + > + // PATH: > + hp_get_string_from_buffer(&buffer_ptr, buffer_size, enum_data->common.path, > + sizeof(enum_data->common.path)); > + > + // IS_READONLY: > + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, > + &enum_data->common.is_readonly); > + > + //DISPLAY_IN_UI: > + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, > + &enum_data->common.display_in_ui); > + > + // REQUIRES_PHYSICAL_PRESENCE: > + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, > + &enum_data->common.requires_physical_presence); > + > + // SEQUENCE: > + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, > + &enum_data->common.sequence); > + > + // PREREQUISITES_SIZE: > + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, > + &enum_data->common.prerequisites_size); > + > + if (enum_data->common.prerequisites_size > MAX_PREREQUISITES_SIZE) { > + /* Report a message and limit prerequisite size to maximum value */ > + pr_warn("Enum Prerequisites size value exceeded the maximum number of elements supported or data may be malformed\n"); > + enum_data->common.prerequisites_size = MAX_PREREQUISITES_SIZE; > + } > + > + // PREREQUISITES: > + for (reqs = 0; reqs < enum_data->common.prerequisites_size; reqs++) > + hp_get_string_from_buffer(&buffer_ptr, buffer_size, > + enum_data->common.prerequisites[reqs], > + sizeof(enum_data->common.prerequisites[reqs])); > + > + // SECURITY_LEVEL: > + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, > + &enum_data->common.security_level); The reading of all the common elemtns can be extracted into a helper and reused from all the attributes. > + > + // ENUM_CURRENT_VALUE: > + hp_get_string_from_buffer(&buffer_ptr, buffer_size, > + enum_data->current_value, > + sizeof(enum_data->current_value)); > + // ENUM_SIZE: > + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, > + &enum_data->possible_values_size); > + > + if (enum_data->possible_values_size > MAX_VALUES_SIZE) { > + /* Report a message and limit possible values size to maximum value */ > + pr_warn("Enum Possible size value exceeded the maximum number of elements supported or data may be malformed\n"); > + enum_data->possible_values_size = MAX_VALUES_SIZE; > + } > + > + // ENUM_POSSIBLE_VALUES: > + > + for (values = 0; values < enum_data->possible_values_size; values++) > + hp_get_string_from_buffer(&buffer_ptr, buffer_size, > + enum_data->possible_values[values], > + sizeof(enum_data->possible_values[values])); > + > + return 0; > +} > + > +/** > + * hp_populate_enumeration_buffer_data() - > + * Populate all properties of an instance under enumeration attribute > + * > + * @buffer_ptr: Buffer pointer > + * @buffer_size: Buffer size > + * @instance_id: The instance to enumerate > + * @attr_name_kobj: The parent kernel object > + */ > +int hp_populate_enumeration_buffer_data(u8 *buffer_ptr, u32 *buffer_size, > + int instance_id, > + struct kobject *attr_name_kobj) > +{ > + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; > + > + enum_data->attr_name_kobj = attr_name_kobj; > + > + /* Populate enumeration elements */ > + hp_populate_enumeration_elements_from_buffer(buffer_ptr, buffer_size, instance_id); > + > + hp_update_attribute_permissions(enum_data->common.is_readonly, > + &enumeration_current_val); > + /* > + * Several attributes have names such "MONDAY". A Friendlier > + * user nane is generated to make the name more descriptive > + */ > + hp_friendly_user_name_update(enum_data->common.path, > + attr_name_kobj->name, > + enum_data->common.display_name, > + sizeof(enum_data->common.display_name)); > + > + return sysfs_create_group(attr_name_kobj, &enumeration_attr_group); > +} > + > +/** > + * hp_exit_enumeration_attributes() - Clear all attribute data > + * > + * Clears all data allocated for this group of attributes > + */ > +void hp_exit_enumeration_attributes(void) > +{ > + int instance_id; > + > + for (instance_id = 0; instance_id < bioscfg_drv.enumeration_instances_count; > + instance_id++) { > + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; > + struct kobject *attr_name_kobj = enum_data->attr_name_kobj; > + > + if (attr_name_kobj) > + sysfs_remove_group(attr_name_kobj, &enumeration_attr_group); > + } > + bioscfg_drv.enumeration_instances_count = 0; > + > + kfree(bioscfg_drv.enumeration_data); > + bioscfg_drv.enumeration_data = NULL; > +} > -- > 2.34.1 >
On Fri, May 26, 2023 at 10:35 AM Thomas Weißschuh <thomas@t-8ch.de> wrote: > > On 2023-05-19 15:12:52-0500, Jorge Lopez wrote: > > <snip> > > > .../x86/hp/hp-bioscfg/enum-attributes.c | 465 ++++++++++++++++++ > > 1 file changed, 465 insertions(+) > > create mode 100644 drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c > > > > diff --git a/drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c b/drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c > > new file mode 100644 > > index 000000000000..80842835606d > > --- /dev/null > > +++ b/drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c > > @@ -0,0 +1,465 @@ > > +// SPDX-License-Identifier: GPL-2.0 > > +/* > > + * Functions corresponding to enumeration type attributes under > > + * BIOS Enumeration GUID for use with hp-bioscfg driver. > > + * > > + * Copyright (c) 2022 HP Development Company, L.P. > > + */ > > + > > +#include "bioscfg.h" > > + > > +GET_INSTANCE_ID(enumeration); > > + > > +static ssize_t current_value_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) > > +{ > > + int instance_id = get_enumeration_instance_id(kobj); > > + > > + if (instance_id < 0) > > + return -EIO; > > + > > + return sysfs_emit(buf, "%s\n", > > + bioscfg_drv.enumeration_data[instance_id].current_value); > > +} > > + > > +/** > > + * validate_enumeration_input() - > > + * Validate input of current_value against possible values > > + * > > + * @instance_id: The instance on which input is validated > > + * @buf: Input value > > + */ <snip> > > +static int hp_populate_enumeration_elements_from_package(union acpi_object *enum_obj, > > + int enum_obj_count, > > + int instance_id) > > +{ > > + char *str_value = NULL; > > + int value_len; > > + u32 size = 0; > > + u32 int_value; > > + int elem = 0; > > + int reqs; > > + int pos_values; > > + int ret; > > + int eloc; > > + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; > > + > > + for (elem = 1, eloc = 1; elem < enum_obj_count; elem++, eloc++) { > > + /* ONLY look at the first ENUM_ELEM_CNT elements */ > > + if (eloc == ENUM_ELEM_CNT) > > + goto exit_enumeration_package; > > + > > + switch (enum_obj[elem].type) { > > + case ACPI_TYPE_STRING: > > + if (PREREQUISITES != elem && ENUM_POSSIBLE_VALUES != elem) { > > + ret = hp_convert_hexstr_to_str(enum_obj[elem].string.pointer, > > + enum_obj[elem].string.length, > > + &str_value, &value_len); > > + if (ret) > > + return -EINVAL; > > + } > > + break; > > + case ACPI_TYPE_INTEGER: > > + int_value = (u32)enum_obj[elem].integer.value; > > + break; > > + default: > > + pr_warn("Unsupported object type [%d]\n", enum_obj[elem].type); > > + continue; > > + } > > + > > + /* Check that both expected and read object type match */ > > + if (expected_enum_types[eloc] != enum_obj[elem].type) { > > + pr_err("Error expected type %d for elem %d, but got type %d instead\n", > > + expected_enum_types[eloc], elem, enum_obj[elem].type); > > + return -EIO; > > + } > > + > > + /* Assign appropriate element value to corresponding field */ > > + switch (eloc) { > > + case NAME: > > + case VALUE: > > + break; > > + case PATH: > > + strscpy(enum_data->common.path, str_value, > > + sizeof(enum_data->common.path)); > > + break; > > + case IS_READONLY: > > + enum_data->common.is_readonly = int_value; > > + break; > > + case DISPLAY_IN_UI: > > + enum_data->common.display_in_ui = int_value; > > + break; > > + case REQUIRES_PHYSICAL_PRESENCE: > > + enum_data->common.requires_physical_presence = int_value; > > + break; > > + case SEQUENCE: > > + enum_data->common.sequence = int_value; > > + break; > > + case PREREQUISITES_SIZE: > > + enum_data->common.prerequisites_size = int_value; > > + if (int_value > MAX_PREREQUISITES_SIZE) > > + pr_warn("Prerequisites size value exceeded the maximum number of elements supported or data may be malformed\n"); > > + > > + /* > > + * This HACK is needed to keep the expected > > + * element list pointing to the right obj[elem].type > > + * when the size is zero. PREREQUISITES > > + * object is omitted by BIOS when the size is > > + * zero. > > + */ > > + if (int_value == 0) > > + eloc++; > > + break; > > + > > + case PREREQUISITES: > > + size = min_t(u32, enum_data->common.prerequisites_size, MAX_PREREQUISITES_SIZE); > > We cannot blindly truncate this to a maximum value. > The firmware reported an amount of elements it would return. > > If this value is to big than we can not just intpret the data as if it > was something the firmware did not return. > > An error needs to be reported to userspace. > A default value is not enough as userspace can not interpret this > properly. > It is ok to truncate prerequisite size to MAX_PREREQUISITES_SIZE. MAX_PREREQUISITES_SIZE is a value predefined by BIOS when the prerequisite values size is invalid ( > MAX_PREREQUISITES_SIZE) and/or the prerequisite data is corrupted. Neither PREREQUISITES nor PREREQUISITES_SIZE are reported to the userspace so there is no need to report a failure on data that is not exposed. One item that needs clarification is the fact that regardless if PREREQUISITES or PREREQUISITES_SIZE are invalid, that does not mean other values are invalid. It is for this reason, we need to continue to read all remaining packages. In earlier reviews, it was agreed to report a warning that reads /* Report a message and limit prerequisite size to maximum value */ pr_warn("Enum Prerequisites size value exceeded the maximum number of elements supported or data may be malformed\n"); See lines 370-374 > (Affects all attributes) > > > + for (reqs = 0; reqs < size; reqs++) { > > + if (elem >= enum_obj_count) { > > + pr_err("Error enum-objects package is too small\n"); > > + return -EINVAL; > > + } > > + > > + ret = hp_convert_hexstr_to_str(enum_obj[elem + reqs].string.pointer, > > + enum_obj[elem + reqs].string.length, > > + &str_value, &value_len); > > + > > + if (ret) > > + return -EINVAL; > > + > > + strscpy(enum_data->common.prerequisites[reqs], > > + str_value, > > + sizeof(enum_data->common.prerequisites[reqs])); > > + > > + kfree(str_value); > > + } > > + break; > > + > > + case SECURITY_LEVEL: > > + enum_data->common.security_level = int_value; > > + break; > > + > > + case ENUM_CURRENT_VALUE: > > + strscpy(enum_data->current_value, > > + str_value, sizeof(enum_data->current_value)); > > + break; > > + case ENUM_SIZE: > > + enum_data->possible_values_size = int_value; > > + if (int_value > MAX_VALUES_SIZE) > > + pr_warn("Possible number values size value exceeded the maximum number of elements supported or data may be malformed\n"); > > + > > + /* > > + * This HACK is needed to keep the expected > > + * element list pointing to the right obj[elem].type > > + * when the size is zero. POSSIBLE_VALUES > > + * object is omitted by BIOS when the size is zero. > > + */ > > + if (int_value == 0) > > + eloc++; > > + break; > > + > > + case ENUM_POSSIBLE_VALUES: > > + size = enum_data->possible_values_size; > > + > > + for (pos_values = 0; pos_values < size && pos_values < MAX_VALUES_SIZE; > > + pos_values++) { > > + if (elem >= enum_obj_count) { > > + pr_err("Error enum-objects package is too small\n"); > > + return -EINVAL; > > + } > > + > > + ret = hp_convert_hexstr_to_str(enum_obj[elem + pos_values].string.pointer, > > + enum_obj[elem + pos_values].string.length, > > + &str_value, &value_len); > > + > > + if (ret) > > + return -EINVAL; > > + > > + /* > > + * ignore strings when possible values size > > + * is greater than MAX_VALUES_SIZE > > + */ > > + if (size < MAX_VALUES_SIZE) > > + strscpy(enum_data->possible_values[pos_values], > > + str_value, > > + sizeof(enum_data->possible_values[pos_values])); > > + } > > + break; > > + default: > > + pr_warn("Invalid element: %d found in Enumeration attribute or data may be malformed\n", elem); > > + break; > > + } > > + > > + kfree(str_value); > > + } > > + > > +exit_enumeration_package: > > + kfree(str_value); > > + return 0; > > +} > > + > > +/** > > + * hp_populate_enumeration_package_data() - > > + * Populate all properties of an instance under enumeration attribute > > + * > > + * @enum_obj: ACPI object with enumeration data > > + * @instance_id: The instance to enumerate > > + * @attr_name_kobj: The parent kernel object > > + */ > > +int hp_populate_enumeration_package_data(union acpi_object *enum_obj, > > + int instance_id, > > + struct kobject *attr_name_kobj) > > +{ > > + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; > > + > > + enum_data->attr_name_kobj = attr_name_kobj; > > + > > + hp_populate_enumeration_elements_from_package(enum_obj, > > + enum_obj->package.count, > > + instance_id); > > + hp_update_attribute_permissions(enum_data->common.is_readonly, > > + &enumeration_current_val); > > + /* > > + * Several attributes have names such "MONDAY". Friendly > > + * user nane is generated to make the name more descriptive > > + */ > > + hp_friendly_user_name_update(enum_data->common.path, > > + attr_name_kobj->name, > > + enum_data->common.display_name, > > + sizeof(enum_data->common.display_name)); > > + return sysfs_create_group(attr_name_kobj, &enumeration_attr_group); > > +} > > + > > +static int hp_populate_enumeration_elements_from_buffer(u8 *buffer_ptr, u32 *buffer_size, > > + int instance_id) > > +{ > > + int reqs; > > + int values; > > + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; > > + > > + /* > > + * In earlier implementation, reported errors were ignored > > + * causing the data to remain uninitialized. It is for this > > + * reason functions may return an error and no validation > > + * takes place. > > + */ > > Where is this error returned? functions such hp_get_string_from_buffer, hp_get_integer_from_buffer > > > + > > + // VALUE: > > + hp_get_string_from_buffer(&buffer_ptr, buffer_size, enum_data->current_value, > > + sizeof(enum_data->current_value)); > > + > > + // PATH: > > + hp_get_string_from_buffer(&buffer_ptr, buffer_size, enum_data->common.path, > > + sizeof(enum_data->common.path)); > > + > > + // IS_READONLY: > > + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, > > + &enum_data->common.is_readonly); > > + > > + //DISPLAY_IN_UI: > > + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, > > + &enum_data->common.display_in_ui); > > + > > + // REQUIRES_PHYSICAL_PRESENCE: > > + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, > > + &enum_data->common.requires_physical_presence); > > + > > + // SEQUENCE: > > + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, > > + &enum_data->common.sequence); > > + > > + // PREREQUISITES_SIZE: > > + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, > > + &enum_data->common.prerequisites_size); > > + > > + if (enum_data->common.prerequisites_size > MAX_PREREQUISITES_SIZE) { > > + /* Report a message and limit prerequisite size to maximum value */ > > + pr_warn("Enum Prerequisites size value exceeded the maximum number of elements supported or data may be malformed\n"); > > + enum_data->common.prerequisites_size = MAX_PREREQUISITES_SIZE; > > + } > > + > > + // PREREQUISITES: > > + for (reqs = 0; reqs < enum_data->common.prerequisites_size; reqs++) > > + hp_get_string_from_buffer(&buffer_ptr, buffer_size, > > + enum_data->common.prerequisites[reqs], > > + sizeof(enum_data->common.prerequisites[reqs])); > > + > > + // SECURITY_LEVEL: > > + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, > > + &enum_data->common.security_level); > > The reading of all the common elemtns can be extracted into a helper > and reused from all the attributes. Is extracting all common elements into a helper routine absolutely necessary now or can it be refactored after driver is accepted? > > > + > > + // ENUM_CURRENT_VALUE: > > + hp_get_string_from_buffer(&buffer_ptr, buffer_size, > > + enum_data->current_value, > > + sizeof(enum_data->current_value)); > > + // ENUM_SIZE: > > + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, > > + &enum_data->possible_values_size); > > + > > + if (enum_data->possible_values_size > MAX_VALUES_SIZE) { > > + /* Report a message and limit possible values size to maximum value */ > > + pr_warn("Enum Possible size value exceeded the maximum number of elements supported or data may be malformed\n"); > > + enum_data->possible_values_size = MAX_VALUES_SIZE; > > + } > > + > > + // ENUM_POSSIBLE_VALUES: > > + > > + for (values = 0; values < enum_data->possible_values_size; values++) > > + hp_get_string_from_buffer(&buffer_ptr, buffer_size, > > + enum_data->possible_values[values], > > + sizeof(enum_data->possible_values[values])); > > + > > + return 0; > > +} > > + > > +/** > > + * hp_populate_enumeration_buffer_data() - > > + * Populate all properties of an instance under enumeration attribute > > + * > > + * @buffer_ptr: Buffer pointer > > + * @buffer_size: Buffer size > > + * @instance_id: The instance to enumerate > > + * @attr_name_kobj: The parent kernel object > > + */ > > +int hp_populate_enumeration_buffer_data(u8 *buffer_ptr, u32 *buffer_size, > > + int instance_id, > > + struct kobject *attr_name_kobj) > > +{ > > + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; > > + > > + enum_data->attr_name_kobj = attr_name_kobj; > > + > > + /* Populate enumeration elements */ > > + hp_populate_enumeration_elements_from_buffer(buffer_ptr, buffer_size, instance_id); > > + > > + hp_update_attribute_permissions(enum_data->common.is_readonly, > > + &enumeration_current_val); > > + /* > > + * Several attributes have names such "MONDAY". A Friendlier > > + * user nane is generated to make the name more descriptive > > + */ > > + hp_friendly_user_name_update(enum_data->common.path, > > + attr_name_kobj->name, > > + enum_data->common.display_name, > > + sizeof(enum_data->common.display_name)); > > + > > + return sysfs_create_group(attr_name_kobj, &enumeration_attr_group); > > +} > > + > > +/** > > + * hp_exit_enumeration_attributes() - Clear all attribute data > > + * > > + * Clears all data allocated for this group of attributes > > + */ > > +void hp_exit_enumeration_attributes(void) > > +{ > > + int instance_id; > > + > > + for (instance_id = 0; instance_id < bioscfg_drv.enumeration_instances_count; > > + instance_id++) { > > + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; > > + struct kobject *attr_name_kobj = enum_data->attr_name_kobj; > > + > > + if (attr_name_kobj) > > + sysfs_remove_group(attr_name_kobj, &enumeration_attr_group); > > + } > > + bioscfg_drv.enumeration_instances_count = 0; > > + > > + kfree(bioscfg_drv.enumeration_data); > > + bioscfg_drv.enumeration_data = NULL; > > +} > > -- > > 2.34.1 > >
On 2023-05-30 12:01:57-0500, Jorge Lopez wrote: > On Fri, May 26, 2023 at 10:35 AM Thomas Weißschuh <thomas@t-8ch.de> wrote: > > > > On 2023-05-19 15:12:52-0500, Jorge Lopez wrote: > > > > <snip> > > > > > .../x86/hp/hp-bioscfg/enum-attributes.c | 465 ++++++++++++++++++ > > > 1 file changed, 465 insertions(+) > > > create mode 100644 drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c > > > > > > diff --git a/drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c b/drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c > > > new file mode 100644 > > > index 000000000000..80842835606d > > > --- /dev/null > > > +++ b/drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c > > > @@ -0,0 +1,465 @@ > > > +// SPDX-License-Identifier: GPL-2.0 > > > +/* > > > + * Functions corresponding to enumeration type attributes under > > > + * BIOS Enumeration GUID for use with hp-bioscfg driver. > > > + * > > > + * Copyright (c) 2022 HP Development Company, L.P. > > > + */ > > > + > > > +#include "bioscfg.h" > > > + > > > +GET_INSTANCE_ID(enumeration); > > > + > > > +static ssize_t current_value_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) > > > +{ > > > + int instance_id = get_enumeration_instance_id(kobj); > > > + > > > + if (instance_id < 0) > > > + return -EIO; > > > + > > > + return sysfs_emit(buf, "%s\n", > > > + bioscfg_drv.enumeration_data[instance_id].current_value); > > > +} > > > + > > > +/** > > > + * validate_enumeration_input() - > > > + * Validate input of current_value against possible values > > > + * > > > + * @instance_id: The instance on which input is validated > > > + * @buf: Input value > > > + */ > > <snip> > > > > +static int hp_populate_enumeration_elements_from_package(union acpi_object *enum_obj, > > > + int enum_obj_count, > > > + int instance_id) > > > +{ > > > + char *str_value = NULL; > > > + int value_len; > > > + u32 size = 0; > > > + u32 int_value; > > > + int elem = 0; > > > + int reqs; > > > + int pos_values; > > > + int ret; > > > + int eloc; > > > + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; > > > + > > > + for (elem = 1, eloc = 1; elem < enum_obj_count; elem++, eloc++) { > > > + /* ONLY look at the first ENUM_ELEM_CNT elements */ > > > + if (eloc == ENUM_ELEM_CNT) > > > + goto exit_enumeration_package; > > > + > > > + switch (enum_obj[elem].type) { > > > + case ACPI_TYPE_STRING: > > > + if (PREREQUISITES != elem && ENUM_POSSIBLE_VALUES != elem) { > > > + ret = hp_convert_hexstr_to_str(enum_obj[elem].string.pointer, > > > + enum_obj[elem].string.length, > > > + &str_value, &value_len); > > > + if (ret) > > > + return -EINVAL; > > > + } > > > + break; > > > + case ACPI_TYPE_INTEGER: > > > + int_value = (u32)enum_obj[elem].integer.value; > > > + break; > > > + default: > > > + pr_warn("Unsupported object type [%d]\n", enum_obj[elem].type); > > > + continue; > > > + } > > > + > > > + /* Check that both expected and read object type match */ > > > + if (expected_enum_types[eloc] != enum_obj[elem].type) { > > > + pr_err("Error expected type %d for elem %d, but got type %d instead\n", > > > + expected_enum_types[eloc], elem, enum_obj[elem].type); > > > + return -EIO; > > > + } > > > + > > > + /* Assign appropriate element value to corresponding field */ > > > + switch (eloc) { > > > + case NAME: > > > + case VALUE: > > > + break; > > > + case PATH: > > > + strscpy(enum_data->common.path, str_value, > > > + sizeof(enum_data->common.path)); > > > + break; > > > + case IS_READONLY: > > > + enum_data->common.is_readonly = int_value; > > > + break; > > > + case DISPLAY_IN_UI: > > > + enum_data->common.display_in_ui = int_value; > > > + break; > > > + case REQUIRES_PHYSICAL_PRESENCE: > > > + enum_data->common.requires_physical_presence = int_value; > > > + break; > > > + case SEQUENCE: > > > + enum_data->common.sequence = int_value; > > > + break; > > > + case PREREQUISITES_SIZE: > > > + enum_data->common.prerequisites_size = int_value; > > > + if (int_value > MAX_PREREQUISITES_SIZE) > > > + pr_warn("Prerequisites size value exceeded the maximum number of elements supported or data may be malformed\n"); > > > + > > > + /* > > > + * This HACK is needed to keep the expected > > > + * element list pointing to the right obj[elem].type > > > + * when the size is zero. PREREQUISITES > > > + * object is omitted by BIOS when the size is > > > + * zero. > > > + */ > > > + if (int_value == 0) > > > + eloc++; > > > + break; > > > + > > > + case PREREQUISITES: > > > + size = min_t(u32, enum_data->common.prerequisites_size, MAX_PREREQUISITES_SIZE); > > > > We cannot blindly truncate this to a maximum value. > > The firmware reported an amount of elements it would return. > > > > If this value is to big than we can not just intpret the data as if it > > was something the firmware did not return. > > > > An error needs to be reported to userspace. > > A default value is not enough as userspace can not interpret this > > properly. > > > > It is ok to truncate prerequisite size to MAX_PREREQUISITES_SIZE. > MAX_PREREQUISITES_SIZE is a value predefined by BIOS when the > prerequisite values size is invalid ( > MAX_PREREQUISITES_SIZE) and/or > the prerequisite data is corrupted. > Neither PREREQUISITES nor PREREQUISITES_SIZE are reported to the > userspace so there is no need to report a failure on data that is not > exposed. One item that needs clarification is the fact that > regardless if PREREQUISITES or PREREQUISITES_SIZE are invalid, that > does not mean other values are invalid. It is for this reason, we > need to continue to read all remaining packages. It may be that prerequisites are not reported to userspace. But the following values are: security level, current value and possible values. And if prerequisites are garbage then those are now also garbage. hp_populate_enumeration_package_data() always returns "0". > In earlier reviews, it was agreed to report a warning that reads > > /* Report a message and limit prerequisite size to maximum value */ > pr_warn("Enum Prerequisites size value exceeded the maximum number of > elements supported or data may be malformed\n"); > > See lines 370-374 > > > (Affects all attributes) > > > > > + for (reqs = 0; reqs < size; reqs++) { > > > + if (elem >= enum_obj_count) { > > > + pr_err("Error enum-objects package is too small\n"); > > > + return -EINVAL; > > > + } > > > + > > > + ret = hp_convert_hexstr_to_str(enum_obj[elem + reqs].string.pointer, > > > + enum_obj[elem + reqs].string.length, > > > + &str_value, &value_len); > > > + > > > + if (ret) > > > + return -EINVAL; > > > + > > > + strscpy(enum_data->common.prerequisites[reqs], > > > + str_value, > > > + sizeof(enum_data->common.prerequisites[reqs])); > > > + > > > + kfree(str_value); > > > + } > > > + break; > > > + > > > + case SECURITY_LEVEL: > > > + enum_data->common.security_level = int_value; > > > + break; > > > + > > > + case ENUM_CURRENT_VALUE: > > > + strscpy(enum_data->current_value, > > > + str_value, sizeof(enum_data->current_value)); > > > + break; > > > + case ENUM_SIZE: > > > + enum_data->possible_values_size = int_value; > > > + if (int_value > MAX_VALUES_SIZE) > > > + pr_warn("Possible number values size value exceeded the maximum number of elements supported or data may be malformed\n"); > > > + > > > + /* > > > + * This HACK is needed to keep the expected > > > + * element list pointing to the right obj[elem].type > > > + * when the size is zero. POSSIBLE_VALUES > > > + * object is omitted by BIOS when the size is zero. > > > + */ > > > + if (int_value == 0) > > > + eloc++; > > > + break; > > > + > > > + case ENUM_POSSIBLE_VALUES: > > > + size = enum_data->possible_values_size; > > > + > > > + for (pos_values = 0; pos_values < size && pos_values < MAX_VALUES_SIZE; > > > + pos_values++) { > > > + if (elem >= enum_obj_count) { > > > + pr_err("Error enum-objects package is too small\n"); > > > + return -EINVAL; > > > + } > > > + > > > + ret = hp_convert_hexstr_to_str(enum_obj[elem + pos_values].string.pointer, > > > + enum_obj[elem + pos_values].string.length, > > > + &str_value, &value_len); > > > + > > > + if (ret) > > > + return -EINVAL; > > > + > > > + /* > > > + * ignore strings when possible values size > > > + * is greater than MAX_VALUES_SIZE > > > + */ > > > + if (size < MAX_VALUES_SIZE) > > > + strscpy(enum_data->possible_values[pos_values], > > > + str_value, > > > + sizeof(enum_data->possible_values[pos_values])); > > > + } > > > + break; > > > + default: > > > + pr_warn("Invalid element: %d found in Enumeration attribute or data may be malformed\n", elem); > > > + break; > > > + } > > > + > > > + kfree(str_value); > > > + } > > > + > > > +exit_enumeration_package: > > > + kfree(str_value); > > > + return 0; > > > +} > > > + > > > +/** > > > + * hp_populate_enumeration_package_data() - > > > + * Populate all properties of an instance under enumeration attribute > > > + * > > > + * @enum_obj: ACPI object with enumeration data > > > + * @instance_id: The instance to enumerate > > > + * @attr_name_kobj: The parent kernel object > > > + */ > > > +int hp_populate_enumeration_package_data(union acpi_object *enum_obj, > > > + int instance_id, > > > + struct kobject *attr_name_kobj) > > > +{ > > > + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; > > > + > > > + enum_data->attr_name_kobj = attr_name_kobj; > > > + > > > + hp_populate_enumeration_elements_from_package(enum_obj, > > > + enum_obj->package.count, > > > + instance_id); > > > + hp_update_attribute_permissions(enum_data->common.is_readonly, > > > + &enumeration_current_val); > > > + /* > > > + * Several attributes have names such "MONDAY". Friendly > > > + * user nane is generated to make the name more descriptive > > > + */ > > > + hp_friendly_user_name_update(enum_data->common.path, > > > + attr_name_kobj->name, > > > + enum_data->common.display_name, > > > + sizeof(enum_data->common.display_name)); > > > + return sysfs_create_group(attr_name_kobj, &enumeration_attr_group); > > > +} > > > + > > > +static int hp_populate_enumeration_elements_from_buffer(u8 *buffer_ptr, u32 *buffer_size, > > > + int instance_id) > > > +{ > > > + int reqs; > > > + int values; > > > + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; > > > + > > > + /* > > > + * In earlier implementation, reported errors were ignored > > > + * causing the data to remain uninitialized. It is for this > > > + * reason functions may return an error and no validation > > > + * takes place. > > > + */ > > > > Where is this error returned? > > functions such hp_get_string_from_buffer, hp_get_integer_from_buffer But the errors returned from those functions are just thrown away, no? > > > > > + > > > + // VALUE: > > > + hp_get_string_from_buffer(&buffer_ptr, buffer_size, enum_data->current_value, > > > + sizeof(enum_data->current_value)); > > > + > > > + // PATH: > > > + hp_get_string_from_buffer(&buffer_ptr, buffer_size, enum_data->common.path, > > > + sizeof(enum_data->common.path)); > > > + > > > + // IS_READONLY: > > > + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, > > > + &enum_data->common.is_readonly); > > > + > > > + //DISPLAY_IN_UI: > > > + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, > > > + &enum_data->common.display_in_ui); > > > + > > > + // REQUIRES_PHYSICAL_PRESENCE: > > > + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, > > > + &enum_data->common.requires_physical_presence); > > > + > > > + // SEQUENCE: > > > + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, > > > + &enum_data->common.sequence); > > > + > > > + // PREREQUISITES_SIZE: > > > + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, > > > + &enum_data->common.prerequisites_size); > > > + > > > + if (enum_data->common.prerequisites_size > MAX_PREREQUISITES_SIZE) { > > > + /* Report a message and limit prerequisite size to maximum value */ > > > + pr_warn("Enum Prerequisites size value exceeded the maximum number of elements supported or data may be malformed\n"); > > > + enum_data->common.prerequisites_size = MAX_PREREQUISITES_SIZE; > > > + } > > > + > > > + // PREREQUISITES: > > > + for (reqs = 0; reqs < enum_data->common.prerequisites_size; reqs++) > > > + hp_get_string_from_buffer(&buffer_ptr, buffer_size, > > > + enum_data->common.prerequisites[reqs], > > > + sizeof(enum_data->common.prerequisites[reqs])); > > > + > > > + // SECURITY_LEVEL: > > > + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, > > > + &enum_data->common.security_level); > > > > The reading of all the common elemtns can be extracted into a helper > > and reused from all the attributes. > > Is extracting all common elements into a helper routine absolutely > necessary now or can it be refactored after driver is accepted? It's not necessary. > > > > > + > > > + // ENUM_CURRENT_VALUE: > > > + hp_get_string_from_buffer(&buffer_ptr, buffer_size, > > > + enum_data->current_value, > > > + sizeof(enum_data->current_value)); > > > + // ENUM_SIZE: > > > + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, > > > + &enum_data->possible_values_size); > > > + > > > + if (enum_data->possible_values_size > MAX_VALUES_SIZE) { > > > + /* Report a message and limit possible values size to maximum value */ > > > + pr_warn("Enum Possible size value exceeded the maximum number of elements supported or data may be malformed\n"); > > > + enum_data->possible_values_size = MAX_VALUES_SIZE; > > > + } > > > + > > > + // ENUM_POSSIBLE_VALUES: > > > + > > > + for (values = 0; values < enum_data->possible_values_size; values++) > > > + hp_get_string_from_buffer(&buffer_ptr, buffer_size, > > > + enum_data->possible_values[values], > > > + sizeof(enum_data->possible_values[values])); > > > + > > > + return 0; > > > +} > > > + > > > +/** > > > + * hp_populate_enumeration_buffer_data() - > > > + * Populate all properties of an instance under enumeration attribute > > > + * > > > + * @buffer_ptr: Buffer pointer > > > + * @buffer_size: Buffer size > > > + * @instance_id: The instance to enumerate > > > + * @attr_name_kobj: The parent kernel object > > > + */ > > > +int hp_populate_enumeration_buffer_data(u8 *buffer_ptr, u32 *buffer_size, > > > + int instance_id, > > > + struct kobject *attr_name_kobj) > > > +{ > > > + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; > > > + > > > + enum_data->attr_name_kobj = attr_name_kobj; > > > + > > > + /* Populate enumeration elements */ > > > + hp_populate_enumeration_elements_from_buffer(buffer_ptr, buffer_size, instance_id); > > > + > > > + hp_update_attribute_permissions(enum_data->common.is_readonly, > > > + &enumeration_current_val); > > > + /* > > > + * Several attributes have names such "MONDAY". A Friendlier > > > + * user nane is generated to make the name more descriptive > > > + */ > > > + hp_friendly_user_name_update(enum_data->common.path, > > > + attr_name_kobj->name, > > > + enum_data->common.display_name, > > > + sizeof(enum_data->common.display_name)); > > > + > > > + return sysfs_create_group(attr_name_kobj, &enumeration_attr_group); > > > +} > > > + > > > +/** > > > + * hp_exit_enumeration_attributes() - Clear all attribute data > > > + * > > > + * Clears all data allocated for this group of attributes > > > + */ > > > +void hp_exit_enumeration_attributes(void) > > > +{ > > > + int instance_id; > > > + > > > + for (instance_id = 0; instance_id < bioscfg_drv.enumeration_instances_count; > > > + instance_id++) { > > > + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; > > > + struct kobject *attr_name_kobj = enum_data->attr_name_kobj; > > > + > > > + if (attr_name_kobj) > > > + sysfs_remove_group(attr_name_kobj, &enumeration_attr_group); > > > + } > > > + bioscfg_drv.enumeration_instances_count = 0; > > > + > > > + kfree(bioscfg_drv.enumeration_data); > > > + bioscfg_drv.enumeration_data = NULL; > > > +} > > > -- > > > 2.34.1 > > >
On Tue, May 30, 2023 at 4:42 PM Thomas Weißschuh <thomas@t-8ch.de> wrote: > > On 2023-05-30 12:01:57-0500, Jorge Lopez wrote: > > On Fri, May 26, 2023 at 10:35 AM Thomas Weißschuh <thomas@t-8ch.de> wrote: > > > > > > On 2023-05-19 15:12:52-0500, Jorge Lopez wrote: > > > > > > <snip> > > > > > > > .../x86/hp/hp-bioscfg/enum-attributes.c | 465 ++++++++++++++++++ > > > > 1 file changed, 465 insertions(+) > > > > create mode 100644 drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c > > > > > > > > diff --git a/drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c b/drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c > > > > new file mode 100644 > > > > index 000000000000..80842835606d > > > > --- /dev/null > > > > +++ b/drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c > > > > @@ -0,0 +1,465 @@ > > > > +// SPDX-License-Identifier: GPL-2.0 > > > > +/* > > > > + * Functions corresponding to enumeration type attributes under > > > > + * BIOS Enumeration GUID for use with hp-bioscfg driver. > > > > + * > > > > + * Copyright (c) 2022 HP Development Company, L.P. > > > > + */ > > > > + > > > > +#include "bioscfg.h" > > > > + > > > > +GET_INSTANCE_ID(enumeration); > > > > + > > > > +static ssize_t current_value_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) > > > > +{ > > > > + int instance_id = get_enumeration_instance_id(kobj); > > > > + > > > > + if (instance_id < 0) > > > > + return -EIO; > > > > + > > > > + return sysfs_emit(buf, "%s\n", > > > > + bioscfg_drv.enumeration_data[instance_id].current_value); > > > > +} > > > > + > > > > +/** > > > > + * validate_enumeration_input() - > > > > + * Validate input of current_value against possible values > > > > + * > > > > + * @instance_id: The instance on which input is validated > > > > + * @buf: Input value > > > > + */ > > > > <snip> > > > > > > +static int hp_populate_enumeration_elements_from_package(union acpi_object *enum_obj, > > > > + int enum_obj_count, > > > > + int instance_id) > > > > +{ > > > > + char *str_value = NULL; > > > > + int value_len; > > > > + u32 size = 0; > > > > + u32 int_value; > > > > + int elem = 0; > > > > + int reqs; > > > > + int pos_values; > > > > + int ret; > > > > + int eloc; > > > > + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; > > > > + > > > > + for (elem = 1, eloc = 1; elem < enum_obj_count; elem++, eloc++) { > > > > + /* ONLY look at the first ENUM_ELEM_CNT elements */ > > > > + if (eloc == ENUM_ELEM_CNT) > > > > + goto exit_enumeration_package; > > > > + > > > > + switch (enum_obj[elem].type) { > > > > + case ACPI_TYPE_STRING: > > > > + if (PREREQUISITES != elem && ENUM_POSSIBLE_VALUES != elem) { > > > > + ret = hp_convert_hexstr_to_str(enum_obj[elem].string.pointer, > > > > + enum_obj[elem].string.length, > > > > + &str_value, &value_len); > > > > + if (ret) > > > > + return -EINVAL; > > > > + } > > > > + break; > > > > + case ACPI_TYPE_INTEGER: > > > > + int_value = (u32)enum_obj[elem].integer.value; > > > > + break; > > > > + default: > > > > + pr_warn("Unsupported object type [%d]\n", enum_obj[elem].type); > > > > + continue; > > > > + } > > > > + > > > > + /* Check that both expected and read object type match */ > > > > + if (expected_enum_types[eloc] != enum_obj[elem].type) { > > > > + pr_err("Error expected type %d for elem %d, but got type %d instead\n", > > > > + expected_enum_types[eloc], elem, enum_obj[elem].type); > > > > + return -EIO; > > > > + } > > > > + > > > > + /* Assign appropriate element value to corresponding field */ > > > > + switch (eloc) { > > > > + case NAME: > > > > + case VALUE: > > > > + break; > > > > + case PATH: > > > > + strscpy(enum_data->common.path, str_value, > > > > + sizeof(enum_data->common.path)); > > > > + break; > > > > + case IS_READONLY: > > > > + enum_data->common.is_readonly = int_value; > > > > + break; > > > > + case DISPLAY_IN_UI: > > > > + enum_data->common.display_in_ui = int_value; > > > > + break; > > > > + case REQUIRES_PHYSICAL_PRESENCE: > > > > + enum_data->common.requires_physical_presence = int_value; > > > > + break; > > > > + case SEQUENCE: > > > > + enum_data->common.sequence = int_value; > > > > + break; > > > > + case PREREQUISITES_SIZE: > > > > + enum_data->common.prerequisites_size = int_value; > > > > + if (int_value > MAX_PREREQUISITES_SIZE) > > > > + pr_warn("Prerequisites size value exceeded the maximum number of elements supported or data may be malformed\n"); > > > > + > > > > + /* > > > > + * This HACK is needed to keep the expected > > > > + * element list pointing to the right obj[elem].type > > > > + * when the size is zero. PREREQUISITES > > > > + * object is omitted by BIOS when the size is > > > > + * zero. > > > > + */ > > > > + if (int_value == 0) > > > > + eloc++; > > > > + break; > > > > + > > > > + case PREREQUISITES: > > > > + size = min_t(u32, enum_data->common.prerequisites_size, MAX_PREREQUISITES_SIZE); > > > > > > We cannot blindly truncate this to a maximum value. > > > The firmware reported an amount of elements it would return. > > > > > > If this value is to big than we can not just intpret the data as if it > > > was something the firmware did not return. > > > > > > An error needs to be reported to userspace. > > > A default value is not enough as userspace can not interpret this > > > properly. > > > > > > > It is ok to truncate prerequisite size to MAX_PREREQUISITES_SIZE. > > MAX_PREREQUISITES_SIZE is a value predefined by BIOS when the > > prerequisite values size is invalid ( > MAX_PREREQUISITES_SIZE) and/or > > the prerequisite data is corrupted. > > Neither PREREQUISITES nor PREREQUISITES_SIZE are reported to the > > userspace so there is no need to report a failure on data that is not > > exposed. One item that needs clarification is the fact that > > regardless if PREREQUISITES or PREREQUISITES_SIZE are invalid, that > > does not mean other values are invalid. It is for this reason, we > > need to continue to read all remaining packages. > > It may be that prerequisites are not reported to userspace. > But the following values are: > > security level, current value and possible values. > > And if prerequisites are garbage then those are now also garbage. This statement is not correct. Each attribute value is isolated from each other hence it only affects a single value and does not impact the following values such security level, current value and possible values Here is a sample where the prerequisite_size is invalid but the prerequisites, security, string min value and string max value are correct. 8003.571287] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite_size 3145848 [ 8003.571287] String Prerequisites size value exceeded the maximum number of elements supported or data may be malformed [ 8003.571288] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[0] /Pci(0x1F,0x6)/MAC(3 [ 8003.571288] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[1] 24D33F453F,0x0)/IPv6(000 [ 8003.571289] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[2] :0000:0000:0000:0000:000 [ 8003.571290] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[3] :0000:0000,0x0,Static,00 [ 8003.571290] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[4] 0:0000:0000:0000:0000:00 [ 8003.571291] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[5] 0:0000:0000,0x40,0000:00 [ 8003.571291] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[6] 0:0000:0000:0000:0000:00 [ 8003.571292] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[7] 0:0000)\r\n\tPciRoot(0x0)/P [ 8003.571292] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[8] i(0x0,0x0)/IPv4(0.0.0.0,0x0,DHCP,0.0.0.0,0.0.0.0, [ 8003.571293] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[9] .0.0.0)\r\n\tPciRoot(0x0)/P [ 8003.571293] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[10] i(0x0,0x0)/IPv6(0000:0000:0000:0000:0000:0000:000 [ 8003.571294] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[11] :0000,0x0,Static,0000:00 [ 8003.571295] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[12] 0:0000:0000:0000:0000:00 [ 8003.571295] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[13] 0:0000,0x0,0000:0000:000 [ 8003.571296] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[14] :0000:0000:0000:0000:000 [ 8003.571296] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[15] ) [ 8003.571297] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[16] [ 8003.571297] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[17] [ 8003.571298] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[18] [ 8003.571298] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[19] [ 8003.571298] Attribute: HP_Disk0MapForUefiBootOrder Security 0 [ 8003.571299] Attribute: HP_Disk0MapForUefiBootOrder String Min Length 0 [ 8003.571299] Attribute: HP_Disk0MapForUefiBootOrder String Max Length 0 > > hp_populate_enumeration_package_data() always returns "0". Earlier in the code, failures reported for a particular attribute value were ignored because each value is independent from each other. It is up to the user space application to analyze the raw data read from BIOS. > > > In earlier reviews, it was agreed to report a warning that reads > > > > /* Report a message and limit prerequisite size to maximum value */ > > pr_warn("Enum Prerequisites size value exceeded the maximum number of > > elements supported or data may be malformed\n"); > > > > See lines 370-374 > > > > > (Affects all attributes) > > > > > > > + for (reqs = 0; reqs < size; reqs++) { > > > > + if (elem >= enum_obj_count) { > > > > + pr_err("Error enum-objects package is too small\n"); > > > > + return -EINVAL; > > > > + } > > > > + > > > > + ret = hp_convert_hexstr_to_str(enum_obj[elem + reqs].string.pointer, > > > > + enum_obj[elem + reqs].string.length, > > > > + &str_value, &value_len); > > > > + > > > > + if (ret) > > > > + return -EINVAL; > > > > + > > > > + strscpy(enum_data->common.prerequisites[reqs], > > > > + str_value, > > > > + sizeof(enum_data->common.prerequisites[reqs])); > > > > + > > > > + kfree(str_value); > > > > + } > > > > + break; > > > > + > > > > + case SECURITY_LEVEL: > > > > + enum_data->common.security_level = int_value; > > > > + break; > > > > + > > > > + case ENUM_CURRENT_VALUE: > > > > + strscpy(enum_data->current_value, > > > > + str_value, sizeof(enum_data->current_value)); > > > > + break; > > > > + case ENUM_SIZE: > > > > + enum_data->possible_values_size = int_value; > > > > + if (int_value > MAX_VALUES_SIZE) > > > > + pr_warn("Possible number values size value exceeded the maximum number of elements supported or data may be malformed\n"); > > > > + > > > > + /* > > > > + * This HACK is needed to keep the expected > > > > + * element list pointing to the right obj[elem].type > > > > + * when the size is zero. POSSIBLE_VALUES > > > > + * object is omitted by BIOS when the size is zero. > > > > + */ > > > > + if (int_value == 0) > > > > + eloc++; > > > > + break; > > > > + > > > > + case ENUM_POSSIBLE_VALUES: > > > > + size = enum_data->possible_values_size; > > > > + > > > > + for (pos_values = 0; pos_values < size && pos_values < MAX_VALUES_SIZE; > > > > + pos_values++) { > > > > + if (elem >= enum_obj_count) { > > > > + pr_err("Error enum-objects package is too small\n"); > > > > + return -EINVAL; > > > > + } > > > > + > > > > + ret = hp_convert_hexstr_to_str(enum_obj[elem + pos_values].string.pointer, > > > > + enum_obj[elem + pos_values].string.length, > > > > + &str_value, &value_len); > > > > + > > > > + if (ret) > > > > + return -EINVAL; > > > > + > > > > + /* > > > > + * ignore strings when possible values size > > > > + * is greater than MAX_VALUES_SIZE > > > > + */ > > > > + if (size < MAX_VALUES_SIZE) > > > > + strscpy(enum_data->possible_values[pos_values], > > > > + str_value, > > > > + sizeof(enum_data->possible_values[pos_values])); > > > > + } > > > > + break; > > > > + default: > > > > + pr_warn("Invalid element: %d found in Enumeration attribute or data may be malformed\n", elem); > > > > + break; > > > > + } > > > > + > > > > + kfree(str_value); > > > > + } > > > > + > > > > +exit_enumeration_package: > > > > + kfree(str_value); > > > > + return 0; > > > > +} > > > > + > > > > +/** > > > > + * hp_populate_enumeration_package_data() - > > > > + * Populate all properties of an instance under enumeration attribute > > > > + * > > > > + * @enum_obj: ACPI object with enumeration data > > > > + * @instance_id: The instance to enumerate > > > > + * @attr_name_kobj: The parent kernel object > > > > + */ > > > > +int hp_populate_enumeration_package_data(union acpi_object *enum_obj, > > > > + int instance_id, > > > > + struct kobject *attr_name_kobj) > > > > +{ > > > > + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; > > > > + > > > > + enum_data->attr_name_kobj = attr_name_kobj; > > > > + > > > > + hp_populate_enumeration_elements_from_package(enum_obj, > > > > + enum_obj->package.count, > > > > + instance_id); > > > > + hp_update_attribute_permissions(enum_data->common.is_readonly, > > > > + &enumeration_current_val); > > > > + /* > > > > + * Several attributes have names such "MONDAY". Friendly > > > > + * user nane is generated to make the name more descriptive > > > > + */ > > > > + hp_friendly_user_name_update(enum_data->common.path, > > > > + attr_name_kobj->name, > > > > + enum_data->common.display_name, > > > > + sizeof(enum_data->common.display_name)); > > > > + return sysfs_create_group(attr_name_kobj, &enumeration_attr_group); > > > > +} > > > > + > > > > +static int hp_populate_enumeration_elements_from_buffer(u8 *buffer_ptr, u32 *buffer_size, > > > > + int instance_id) > > > > +{ > > > > + int reqs; > > > > + int values; > > > > + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; > > > > + > > > > + /* > > > > + * In earlier implementation, reported errors were ignored > > > > + * causing the data to remain uninitialized. It is for this > > > > + * reason functions may return an error and no validation > > > > + * takes place. > > > > + */ > > > > > > Where is this error returned? > > > > functions such hp_get_string_from_buffer, hp_get_integer_from_buffer > > But the errors returned from those functions are just thrown away, no? Earlier in the code, failures reported for a particular attribute value were ignored because each value is independent from each other. It is for this reason, we are throwing away any errors returned from those functions. > > > > > > > + > > > > + // VALUE: > > > > + hp_get_string_from_buffer(&buffer_ptr, buffer_size, enum_data->current_value, > > > > + sizeof(enum_data->current_value)); > > > > + > > > > + // PATH: > > > > + hp_get_string_from_buffer(&buffer_ptr, buffer_size, enum_data->common.path, > > > > + sizeof(enum_data->common.path)); > > > > + > > > > + // IS_READONLY: > > > > + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, > > > > + &enum_data->common.is_readonly); > > > > + > > > > + //DISPLAY_IN_UI: > > > > + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, > > > > + &enum_data->common.display_in_ui); > > > > + > > > > + // REQUIRES_PHYSICAL_PRESENCE: > > > > + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, > > > > + &enum_data->common.requires_physical_presence); > > > > + > > > > + // SEQUENCE: > > > > + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, > > > > + &enum_data->common.sequence); > > > > + > > > > + // PREREQUISITES_SIZE: > > > > + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, > > > > + &enum_data->common.prerequisites_size); > > > > + > > > > + if (enum_data->common.prerequisites_size > MAX_PREREQUISITES_SIZE) { > > > > + /* Report a message and limit prerequisite size to maximum value */ > > > > + pr_warn("Enum Prerequisites size value exceeded the maximum number of elements supported or data may be malformed\n"); > > > > + enum_data->common.prerequisites_size = MAX_PREREQUISITES_SIZE; > > > > + } > > > > + > > > > + // PREREQUISITES: > > > > + for (reqs = 0; reqs < enum_data->common.prerequisites_size; reqs++) > > > > + hp_get_string_from_buffer(&buffer_ptr, buffer_size, > > > > + enum_data->common.prerequisites[reqs], > > > > + sizeof(enum_data->common.prerequisites[reqs])); > > > > + > > > > + // SECURITY_LEVEL: > > > > + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, > > > > + &enum_data->common.security_level); > > > > > > The reading of all the common elemtns can be extracted into a helper > > > and reused from all the attributes. > > > > Is extracting all common elements into a helper routine absolutely > > necessary now or can it be refactored after driver is accepted? > > It's not necessary. Thank you > > > > > > > > + > > > > + // ENUM_CURRENT_VALUE: > > > > + hp_get_string_from_buffer(&buffer_ptr, buffer_size, > > > > + enum_data->current_value, > > > > + sizeof(enum_data->current_value)); > > > > + // ENUM_SIZE: > > > > + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, > > > > + &enum_data->possible_values_size); > > > > + > > > > + if (enum_data->possible_values_size > MAX_VALUES_SIZE) { > > > > + /* Report a message and limit possible values size to maximum value */ > > > > + pr_warn("Enum Possible size value exceeded the maximum number of elements supported or data may be malformed\n"); > > > > + enum_data->possible_values_size = MAX_VALUES_SIZE; > > > > + } > > > > + > > > > + // ENUM_POSSIBLE_VALUES: > > > > + > > > > + for (values = 0; values < enum_data->possible_values_size; values++) > > > > + hp_get_string_from_buffer(&buffer_ptr, buffer_size, > > > > + enum_data->possible_values[values], > > > > + sizeof(enum_data->possible_values[values])); > > > > + > > > > + return 0; > > > > +} > > > > + > > > > +/** > > > > + * hp_populate_enumeration_buffer_data() - > > > > + * Populate all properties of an instance under enumeration attribute > > > > + * > > > > + * @buffer_ptr: Buffer pointer > > > > + * @buffer_size: Buffer size > > > > + * @instance_id: The instance to enumerate > > > > + * @attr_name_kobj: The parent kernel object > > > > + */ > > > > +int hp_populate_enumeration_buffer_data(u8 *buffer_ptr, u32 *buffer_size, > > > > + int instance_id, > > > > + struct kobject *attr_name_kobj) > > > > +{ > > > > + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; > > > > + > > > > + enum_data->attr_name_kobj = attr_name_kobj; > > > > + > > > > + /* Populate enumeration elements */ > > > > + hp_populate_enumeration_elements_from_buffer(buffer_ptr, buffer_size, instance_id); > > > > + > > > > + hp_update_attribute_permissions(enum_data->common.is_readonly, > > > > + &enumeration_current_val); > > > > + /* > > > > + * Several attributes have names such "MONDAY". A Friendlier > > > > + * user nane is generated to make the name more descriptive > > > > + */ > > > > + hp_friendly_user_name_update(enum_data->common.path, > > > > + attr_name_kobj->name, > > > > + enum_data->common.display_name, > > > > + sizeof(enum_data->common.display_name)); > > > > + > > > > + return sysfs_create_group(attr_name_kobj, &enumeration_attr_group); > > > > +} > > > > + > > > > +/** > > > > + * hp_exit_enumeration_attributes() - Clear all attribute data > > > > + * > > > > + * Clears all data allocated for this group of attributes > > > > + */ > > > > +void hp_exit_enumeration_attributes(void) > > > > +{ > > > > + int instance_id; > > > > + > > > > + for (instance_id = 0; instance_id < bioscfg_drv.enumeration_instances_count; > > > > + instance_id++) { > > > > + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; > > > > + struct kobject *attr_name_kobj = enum_data->attr_name_kobj; > > > > + > > > > + if (attr_name_kobj) > > > > + sysfs_remove_group(attr_name_kobj, &enumeration_attr_group); > > > > + } > > > > + bioscfg_drv.enumeration_instances_count = 0; > > > > + > > > > + kfree(bioscfg_drv.enumeration_data); > > > > + bioscfg_drv.enumeration_data = NULL; > > > > +} > > > > -- > > > > 2.34.1 > > > >
On 2023-05-31 10:59:58-0500, Jorge Lopez wrote: > On Tue, May 30, 2023 at 4:42 PM Thomas Weißschuh <thomas@t-8ch.de> wrote: > > > > On 2023-05-30 12:01:57-0500, Jorge Lopez wrote: > > > On Fri, May 26, 2023 at 10:35 AM Thomas Weißschuh <thomas@t-8ch.de> wrote: > > > > > > > > On 2023-05-19 15:12:52-0500, Jorge Lopez wrote: > > > > > > > > <snip> > > > > > > > > > .../x86/hp/hp-bioscfg/enum-attributes.c | 465 ++++++++++++++++++ > > > > > 1 file changed, 465 insertions(+) > > > > > create mode 100644 drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c > > > > > > > > > > diff --git a/drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c b/drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c > > > > > new file mode 100644 > > > > > index 000000000000..80842835606d > > > > > --- /dev/null > > > > > +++ b/drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c > > > > > @@ -0,0 +1,465 @@ > > > > > +// SPDX-License-Identifier: GPL-2.0 > > > > > +/* > > > > > + * Functions corresponding to enumeration type attributes under > > > > > + * BIOS Enumeration GUID for use with hp-bioscfg driver. > > > > > + * > > > > > + * Copyright (c) 2022 HP Development Company, L.P. > > > > > + */ > > > > > + > > > > > +#include "bioscfg.h" > > > > > + > > > > > +GET_INSTANCE_ID(enumeration); > > > > > + > > > > > +static ssize_t current_value_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) > > > > > +{ > > > > > + int instance_id = get_enumeration_instance_id(kobj); > > > > > + > > > > > + if (instance_id < 0) > > > > > + return -EIO; > > > > > + > > > > > + return sysfs_emit(buf, "%s\n", > > > > > + bioscfg_drv.enumeration_data[instance_id].current_value); > > > > > +} > > > > > + > > > > > +/** > > > > > + * validate_enumeration_input() - > > > > > + * Validate input of current_value against possible values > > > > > + * > > > > > + * @instance_id: The instance on which input is validated > > > > > + * @buf: Input value > > > > > + */ > > > > > > <snip> > > > > > > > > +static int hp_populate_enumeration_elements_from_package(union acpi_object *enum_obj, > > > > > + int enum_obj_count, > > > > > + int instance_id) > > > > > +{ > > > > > + char *str_value = NULL; > > > > > + int value_len; > > > > > + u32 size = 0; > > > > > + u32 int_value; > > > > > + int elem = 0; > > > > > + int reqs; > > > > > + int pos_values; > > > > > + int ret; > > > > > + int eloc; > > > > > + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; > > > > > + > > > > > + for (elem = 1, eloc = 1; elem < enum_obj_count; elem++, eloc++) { > > > > > + /* ONLY look at the first ENUM_ELEM_CNT elements */ > > > > > + if (eloc == ENUM_ELEM_CNT) > > > > > + goto exit_enumeration_package; > > > > > + > > > > > + switch (enum_obj[elem].type) { > > > > > + case ACPI_TYPE_STRING: > > > > > + if (PREREQUISITES != elem && ENUM_POSSIBLE_VALUES != elem) { > > > > > + ret = hp_convert_hexstr_to_str(enum_obj[elem].string.pointer, > > > > > + enum_obj[elem].string.length, > > > > > + &str_value, &value_len); > > > > > + if (ret) > > > > > + return -EINVAL; > > > > > + } > > > > > + break; > > > > > + case ACPI_TYPE_INTEGER: > > > > > + int_value = (u32)enum_obj[elem].integer.value; > > > > > + break; > > > > > + default: > > > > > + pr_warn("Unsupported object type [%d]\n", enum_obj[elem].type); > > > > > + continue; > > > > > + } > > > > > + > > > > > + /* Check that both expected and read object type match */ > > > > > + if (expected_enum_types[eloc] != enum_obj[elem].type) { > > > > > + pr_err("Error expected type %d for elem %d, but got type %d instead\n", > > > > > + expected_enum_types[eloc], elem, enum_obj[elem].type); > > > > > + return -EIO; > > > > > + } > > > > > + > > > > > + /* Assign appropriate element value to corresponding field */ > > > > > + switch (eloc) { > > > > > + case NAME: > > > > > + case VALUE: > > > > > + break; > > > > > + case PATH: > > > > > + strscpy(enum_data->common.path, str_value, > > > > > + sizeof(enum_data->common.path)); > > > > > + break; > > > > > + case IS_READONLY: > > > > > + enum_data->common.is_readonly = int_value; > > > > > + break; > > > > > + case DISPLAY_IN_UI: > > > > > + enum_data->common.display_in_ui = int_value; > > > > > + break; > > > > > + case REQUIRES_PHYSICAL_PRESENCE: > > > > > + enum_data->common.requires_physical_presence = int_value; > > > > > + break; > > > > > + case SEQUENCE: > > > > > + enum_data->common.sequence = int_value; > > > > > + break; > > > > > + case PREREQUISITES_SIZE: > > > > > + enum_data->common.prerequisites_size = int_value; > > > > > + if (int_value > MAX_PREREQUISITES_SIZE) > > > > > + pr_warn("Prerequisites size value exceeded the maximum number of elements supported or data may be malformed\n"); > > > > > + > > > > > + /* > > > > > + * This HACK is needed to keep the expected > > > > > + * element list pointing to the right obj[elem].type > > > > > + * when the size is zero. PREREQUISITES > > > > > + * object is omitted by BIOS when the size is > > > > > + * zero. > > > > > + */ > > > > > + if (int_value == 0) > > > > > + eloc++; > > > > > + break; > > > > > + > > > > > + case PREREQUISITES: > > > > > + size = min_t(u32, enum_data->common.prerequisites_size, MAX_PREREQUISITES_SIZE); > > > > > > > > We cannot blindly truncate this to a maximum value. > > > > The firmware reported an amount of elements it would return. > > > > > > > > If this value is to big than we can not just intpret the data as if it > > > > was something the firmware did not return. > > > > > > > > An error needs to be reported to userspace. > > > > A default value is not enough as userspace can not interpret this > > > > properly. > > > > > > > > > > It is ok to truncate prerequisite size to MAX_PREREQUISITES_SIZE. > > > MAX_PREREQUISITES_SIZE is a value predefined by BIOS when the > > > prerequisite values size is invalid ( > MAX_PREREQUISITES_SIZE) and/or > > > the prerequisite data is corrupted. > > > Neither PREREQUISITES nor PREREQUISITES_SIZE are reported to the > > > userspace so there is no need to report a failure on data that is not > > > exposed. One item that needs clarification is the fact that > > > regardless if PREREQUISITES or PREREQUISITES_SIZE are invalid, that > > > does not mean other values are invalid. It is for this reason, we > > > need to continue to read all remaining packages. > > > > It may be that prerequisites are not reported to userspace. > > But the following values are: > > > > security level, current value and possible values. > > > > And if prerequisites are garbage then those are now also garbage. > > This statement is not correct. Each attribute value is isolated from > each other hence it only affects a single value and does not impact > the following values such security level, current value and possible > values Indeed, I stand corrected. I guess the loop-based logic is still confusing me. > Here is a sample where the prerequisite_size is invalid but the > prerequisites, security, string min value and string max value are > correct. > > 8003.571287] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite_size 3145848 > [ 8003.571287] String Prerequisites size value exceeded the maximum > number of elements supported or data may be malformed > > [ 8003.571288] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[0] > /Pci(0x1F,0x6)/MAC(3 > [ 8003.571288] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[1] > 24D33F453F,0x0)/IPv6(000 > [ 8003.571289] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[2] > :0000:0000:0000:0000:000 > [ 8003.571290] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[3] > :0000:0000,0x0,Static,00 > [ 8003.571290] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[4] > 0:0000:0000:0000:0000:00 > [ 8003.571291] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[5] > 0:0000:0000,0x40,0000:00 > [ 8003.571291] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[6] > 0:0000:0000:0000:0000:00 > [ 8003.571292] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[7] > 0:0000)\r\n\tPciRoot(0x0)/P > [ 8003.571292] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[8] > i(0x0,0x0)/IPv4(0.0.0.0,0x0,DHCP,0.0.0.0,0.0.0.0, > [ 8003.571293] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[9] > .0.0.0)\r\n\tPciRoot(0x0)/P > [ 8003.571293] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[10] > i(0x0,0x0)/IPv6(0000:0000:0000:0000:0000:0000:000 > [ 8003.571294] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[11] > :0000,0x0,Static,0000:00 > [ 8003.571295] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[12] > 0:0000:0000:0000:0000:00 > [ 8003.571295] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[13] > 0:0000,0x0,0000:0000:000 > [ 8003.571296] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[14] > :0000:0000:0000:0000:000 > [ 8003.571296] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[15] ) > [ 8003.571297] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[16] > [ 8003.571297] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[17] > [ 8003.571298] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[18] > [ 8003.571298] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[19] > > [ 8003.571298] Attribute: HP_Disk0MapForUefiBootOrder Security 0 > [ 8003.571299] Attribute: HP_Disk0MapForUefiBootOrder String Min Length 0 > [ 8003.571299] Attribute: HP_Disk0MapForUefiBootOrder String Max Length 0 > > > > > > hp_populate_enumeration_package_data() always returns "0". > > Earlier in the code, failures reported for a particular attribute > value were ignored because each value is independent from each other. > It is up to the user space application to analyze the raw data read from BIOS. Please remember that this API will not only be used by HPs own userspace component. Where are the rules for userspace documented to analyze the raw data and recognize an error? Looking at the kernel log is not enough, it is not an API. > > > > > In earlier reviews, it was agreed to report a warning that reads > > > > > > /* Report a message and limit prerequisite size to maximum value */ > > > pr_warn("Enum Prerequisites size value exceeded the maximum number of > > > elements supported or data may be malformed\n"); > > > > > > See lines 370-374 > > > > > > > (Affects all attributes) > > > > > > > > > + for (reqs = 0; reqs < size; reqs++) { > > > > > + if (elem >= enum_obj_count) { > > > > > + pr_err("Error enum-objects package is too small\n"); > > > > > + return -EINVAL; > > > > > + } > > > > > + > > > > > + ret = hp_convert_hexstr_to_str(enum_obj[elem + reqs].string.pointer, > > > > > + enum_obj[elem + reqs].string.length, > > > > > + &str_value, &value_len); > > > > > + > > > > > + if (ret) > > > > > + return -EINVAL; > > > > > + > > > > > + strscpy(enum_data->common.prerequisites[reqs], > > > > > + str_value, > > > > > + sizeof(enum_data->common.prerequisites[reqs])); > > > > > + > > > > > + kfree(str_value); > > > > > + } > > > > > + break; > > > > > + > > > > > + case SECURITY_LEVEL: > > > > > + enum_data->common.security_level = int_value; > > > > > + break; > > > > > + > > > > > + case ENUM_CURRENT_VALUE: > > > > > + strscpy(enum_data->current_value, > > > > > + str_value, sizeof(enum_data->current_value)); > > > > > + break; > > > > > + case ENUM_SIZE: > > > > > + enum_data->possible_values_size = int_value; > > > > > + if (int_value > MAX_VALUES_SIZE) > > > > > + pr_warn("Possible number values size value exceeded the maximum number of elements supported or data may be malformed\n"); > > > > > + > > > > > + /* > > > > > + * This HACK is needed to keep the expected > > > > > + * element list pointing to the right obj[elem].type > > > > > + * when the size is zero. POSSIBLE_VALUES > > > > > + * object is omitted by BIOS when the size is zero. > > > > > + */ > > > > > + if (int_value == 0) > > > > > + eloc++; > > > > > + break; > > > > > + > > > > > + case ENUM_POSSIBLE_VALUES: > > > > > + size = enum_data->possible_values_size; > > > > > + > > > > > + for (pos_values = 0; pos_values < size && pos_values < MAX_VALUES_SIZE; > > > > > + pos_values++) { > > > > > + if (elem >= enum_obj_count) { > > > > > + pr_err("Error enum-objects package is too small\n"); > > > > > + return -EINVAL; > > > > > + } > > > > > + > > > > > + ret = hp_convert_hexstr_to_str(enum_obj[elem + pos_values].string.pointer, > > > > > + enum_obj[elem + pos_values].string.length, > > > > > + &str_value, &value_len); > > > > > + > > > > > + if (ret) > > > > > + return -EINVAL; > > > > > + > > > > > + /* > > > > > + * ignore strings when possible values size > > > > > + * is greater than MAX_VALUES_SIZE > > > > > + */ > > > > > + if (size < MAX_VALUES_SIZE) > > > > > + strscpy(enum_data->possible_values[pos_values], > > > > > + str_value, > > > > > + sizeof(enum_data->possible_values[pos_values])); > > > > > + } > > > > > + break; > > > > > + default: > > > > > + pr_warn("Invalid element: %d found in Enumeration attribute or data may be malformed\n", elem); > > > > > + break; > > > > > + } > > > > > + > > > > > + kfree(str_value); > > > > > + } > > > > > + > > > > > +exit_enumeration_package: > > > > > + kfree(str_value); > > > > > + return 0; > > > > > +} > > > > > + > > > > > +/** > > > > > + * hp_populate_enumeration_package_data() - > > > > > + * Populate all properties of an instance under enumeration attribute > > > > > + * > > > > > + * @enum_obj: ACPI object with enumeration data > > > > > + * @instance_id: The instance to enumerate > > > > > + * @attr_name_kobj: The parent kernel object > > > > > + */ > > > > > +int hp_populate_enumeration_package_data(union acpi_object *enum_obj, > > > > > + int instance_id, > > > > > + struct kobject *attr_name_kobj) > > > > > +{ > > > > > + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; > > > > > + > > > > > + enum_data->attr_name_kobj = attr_name_kobj; > > > > > + > > > > > + hp_populate_enumeration_elements_from_package(enum_obj, > > > > > + enum_obj->package.count, > > > > > + instance_id); > > > > > + hp_update_attribute_permissions(enum_data->common.is_readonly, > > > > > + &enumeration_current_val); > > > > > + /* > > > > > + * Several attributes have names such "MONDAY". Friendly > > > > > + * user nane is generated to make the name more descriptive > > > > > + */ > > > > > + hp_friendly_user_name_update(enum_data->common.path, > > > > > + attr_name_kobj->name, > > > > > + enum_data->common.display_name, > > > > > + sizeof(enum_data->common.display_name)); > > > > > + return sysfs_create_group(attr_name_kobj, &enumeration_attr_group); > > > > > +} > > > > > + > > > > > +static int hp_populate_enumeration_elements_from_buffer(u8 *buffer_ptr, u32 *buffer_size, > > > > > + int instance_id) > > > > > +{ > > > > > + int reqs; > > > > > + int values; > > > > > + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; > > > > > + > > > > > + /* > > > > > + * In earlier implementation, reported errors were ignored > > > > > + * causing the data to remain uninitialized. It is for this > > > > > + * reason functions may return an error and no validation > > > > > + * takes place. > > > > > + */ > > > > > > > > Where is this error returned? > > > > > > functions such hp_get_string_from_buffer, hp_get_integer_from_buffer > > > > But the errors returned from those functions are just thrown away, no? > > Earlier in the code, failures reported for a particular attribute > value were ignored because each value is independent from each other. > It is for this reason, we are throwing away any errors returned from > those functions. > > > > > > > > > > + > > > > > + // VALUE: > > > > > + hp_get_string_from_buffer(&buffer_ptr, buffer_size, enum_data->current_value, > > > > > + sizeof(enum_data->current_value)); > > > > > + > > > > > + // PATH: > > > > > + hp_get_string_from_buffer(&buffer_ptr, buffer_size, enum_data->common.path, > > > > > + sizeof(enum_data->common.path)); > > > > > + > > > > > + // IS_READONLY: > > > > > + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, > > > > > + &enum_data->common.is_readonly); > > > > > + > > > > > + //DISPLAY_IN_UI: > > > > > + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, > > > > > + &enum_data->common.display_in_ui); > > > > > + > > > > > + // REQUIRES_PHYSICAL_PRESENCE: > > > > > + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, > > > > > + &enum_data->common.requires_physical_presence); > > > > > + > > > > > + // SEQUENCE: > > > > > + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, > > > > > + &enum_data->common.sequence); > > > > > + > > > > > + // PREREQUISITES_SIZE: > > > > > + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, > > > > > + &enum_data->common.prerequisites_size); > > > > > + > > > > > + if (enum_data->common.prerequisites_size > MAX_PREREQUISITES_SIZE) { > > > > > + /* Report a message and limit prerequisite size to maximum value */ > > > > > + pr_warn("Enum Prerequisites size value exceeded the maximum number of elements supported or data may be malformed\n"); > > > > > + enum_data->common.prerequisites_size = MAX_PREREQUISITES_SIZE; > > > > > + } > > > > > + > > > > > + // PREREQUISITES: > > > > > + for (reqs = 0; reqs < enum_data->common.prerequisites_size; reqs++) > > > > > + hp_get_string_from_buffer(&buffer_ptr, buffer_size, > > > > > + enum_data->common.prerequisites[reqs], > > > > > + sizeof(enum_data->common.prerequisites[reqs])); > > > > > + > > > > > + // SECURITY_LEVEL: > > > > > + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, > > > > > + &enum_data->common.security_level); > > > > > > > > The reading of all the common elemtns can be extracted into a helper > > > > and reused from all the attributes. > > > > > > Is extracting all common elements into a helper routine absolutely > > > necessary now or can it be refactored after driver is accepted? > > > > It's not necessary. > > Thank you > > > > > > > > > > > + > > > > > + // ENUM_CURRENT_VALUE: > > > > > + hp_get_string_from_buffer(&buffer_ptr, buffer_size, > > > > > + enum_data->current_value, > > > > > + sizeof(enum_data->current_value)); > > > > > + // ENUM_SIZE: > > > > > + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, > > > > > + &enum_data->possible_values_size); > > > > > + > > > > > + if (enum_data->possible_values_size > MAX_VALUES_SIZE) { > > > > > + /* Report a message and limit possible values size to maximum value */ > > > > > + pr_warn("Enum Possible size value exceeded the maximum number of elements supported or data may be malformed\n"); > > > > > + enum_data->possible_values_size = MAX_VALUES_SIZE; > > > > > + } > > > > > + > > > > > + // ENUM_POSSIBLE_VALUES: > > > > > + > > > > > + for (values = 0; values < enum_data->possible_values_size; values++) > > > > > + hp_get_string_from_buffer(&buffer_ptr, buffer_size, > > > > > + enum_data->possible_values[values], > > > > > + sizeof(enum_data->possible_values[values])); > > > > > + > > > > > + return 0; > > > > > +} > > > > > + > > > > > +/** > > > > > + * hp_populate_enumeration_buffer_data() - > > > > > + * Populate all properties of an instance under enumeration attribute > > > > > + * > > > > > + * @buffer_ptr: Buffer pointer > > > > > + * @buffer_size: Buffer size > > > > > + * @instance_id: The instance to enumerate > > > > > + * @attr_name_kobj: The parent kernel object > > > > > + */ > > > > > +int hp_populate_enumeration_buffer_data(u8 *buffer_ptr, u32 *buffer_size, > > > > > + int instance_id, > > > > > + struct kobject *attr_name_kobj) > > > > > +{ > > > > > + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; > > > > > + > > > > > + enum_data->attr_name_kobj = attr_name_kobj; > > > > > + > > > > > + /* Populate enumeration elements */ > > > > > + hp_populate_enumeration_elements_from_buffer(buffer_ptr, buffer_size, instance_id); > > > > > + > > > > > + hp_update_attribute_permissions(enum_data->common.is_readonly, > > > > > + &enumeration_current_val); > > > > > + /* > > > > > + * Several attributes have names such "MONDAY". A Friendlier > > > > > + * user nane is generated to make the name more descriptive > > > > > + */ > > > > > + hp_friendly_user_name_update(enum_data->common.path, > > > > > + attr_name_kobj->name, > > > > > + enum_data->common.display_name, > > > > > + sizeof(enum_data->common.display_name)); > > > > > + > > > > > + return sysfs_create_group(attr_name_kobj, &enumeration_attr_group); > > > > > +} > > > > > + > > > > > +/** > > > > > + * hp_exit_enumeration_attributes() - Clear all attribute data > > > > > + * > > > > > + * Clears all data allocated for this group of attributes > > > > > + */ > > > > > +void hp_exit_enumeration_attributes(void) > > > > > +{ > > > > > + int instance_id; > > > > > + > > > > > + for (instance_id = 0; instance_id < bioscfg_drv.enumeration_instances_count; > > > > > + instance_id++) { > > > > > + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; > > > > > + struct kobject *attr_name_kobj = enum_data->attr_name_kobj; > > > > > + > > > > > + if (attr_name_kobj) > > > > > + sysfs_remove_group(attr_name_kobj, &enumeration_attr_group); > > > > > + } > > > > > + bioscfg_drv.enumeration_instances_count = 0; > > > > > + > > > > > + kfree(bioscfg_drv.enumeration_data); > > > > > + bioscfg_drv.enumeration_data = NULL; > > > > > +} > > > > > -- > > > > > 2.34.1 > > > > >
On Sat, Jun 3, 2023 at 1:35 AM Thomas Weißschuh <thomas@t-8ch.de> wrote: > > On 2023-05-31 10:59:58-0500, Jorge Lopez wrote: > > On Tue, May 30, 2023 at 4:42 PM Thomas Weißschuh <thomas@t-8ch.de> wrote: > > > > > > On 2023-05-30 12:01:57-0500, Jorge Lopez wrote: > > > > On Fri, May 26, 2023 at 10:35 AM Thomas Weißschuh <thomas@t-8ch.de> wrote: > > > > > > > > > > On 2023-05-19 15:12:52-0500, Jorge Lopez wrote: > > > > > > > > > > <snip> > > > > > > > > > > > .../x86/hp/hp-bioscfg/enum-attributes.c | 465 ++++++++++++++++++ > > > > > > 1 file changed, 465 insertions(+) > > > > > > create mode 100644 drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c > > > > > > > > > > > > diff --git a/drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c b/drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c > > > > > > new file mode 100644 > > > > > > index 000000000000..80842835606d > > > > > > --- /dev/null > > > > > > +++ b/drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c > > > > > > @@ -0,0 +1,465 @@ > > > > > > +// SPDX-License-Identifier: GPL-2.0 > > > > > > +/* > > > > > > + * Functions corresponding to enumeration type attributes under > > > > > > + * BIOS Enumeration GUID for use with hp-bioscfg driver. > > > > > > + * > > > > > > + * Copyright (c) 2022 HP Development Company, L.P. > > > > > > + */ > > > > > > + > > > > > > +#include "bioscfg.h" > > > > > > + > > > > > > +GET_INSTANCE_ID(enumeration); > > > > > > + > > > > > > +static ssize_t current_value_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) > > > > > > +{ > > > > > > + int instance_id = get_enumeration_instance_id(kobj); > > > > > > + > > > > > > + if (instance_id < 0) > > > > > > + return -EIO; > > > > > > + > > > > > > + return sysfs_emit(buf, "%s\n", > > > > > > + bioscfg_drv.enumeration_data[instance_id].current_value); > > > > > > +} > > > > > > + > > > > > > +/** > > > > > > + * validate_enumeration_input() - > > > > > > + * Validate input of current_value against possible values > > > > > > + * > > > > > > + * @instance_id: The instance on which input is validated > > > > > > + * @buf: Input value > > > > > > + */ > > > > > > > > <snip> > > > > > > > > > > +static int hp_populate_enumeration_elements_from_package(union acpi_object *enum_obj, > > > > > > + int enum_obj_count, > > > > > > + int instance_id) > > > > > > +{ > > > > > > + char *str_value = NULL; > > > > > > + int value_len; > > > > > > + u32 size = 0; > > > > > > + u32 int_value; > > > > > > + int elem = 0; > > > > > > + int reqs; > > > > > > + int pos_values; > > > > > > + int ret; > > > > > > + int eloc; > > > > > > + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; > > > > > > + > > > > > > + for (elem = 1, eloc = 1; elem < enum_obj_count; elem++, eloc++) { > > > > > > + /* ONLY look at the first ENUM_ELEM_CNT elements */ > > > > > > + if (eloc == ENUM_ELEM_CNT) > > > > > > + goto exit_enumeration_package; > > > > > > + > > > > > > + switch (enum_obj[elem].type) { > > > > > > + case ACPI_TYPE_STRING: > > > > > > + if (PREREQUISITES != elem && ENUM_POSSIBLE_VALUES != elem) { > > > > > > + ret = hp_convert_hexstr_to_str(enum_obj[elem].string.pointer, > > > > > > + enum_obj[elem].string.length, > > > > > > + &str_value, &value_len); > > > > > > + if (ret) > > > > > > + return -EINVAL; > > > > > > + } > > > > > > + break; > > > > > > + case ACPI_TYPE_INTEGER: > > > > > > + int_value = (u32)enum_obj[elem].integer.value; > > > > > > + break; > > > > > > + default: > > > > > > + pr_warn("Unsupported object type [%d]\n", enum_obj[elem].type); > > > > > > + continue; > > > > > > + } > > > > > > + > > > > > > + /* Check that both expected and read object type match */ > > > > > > + if (expected_enum_types[eloc] != enum_obj[elem].type) { > > > > > > + pr_err("Error expected type %d for elem %d, but got type %d instead\n", > > > > > > + expected_enum_types[eloc], elem, enum_obj[elem].type); > > > > > > + return -EIO; > > > > > > + } > > > > > > + > > > > > > + /* Assign appropriate element value to corresponding field */ > > > > > > + switch (eloc) { > > > > > > + case NAME: > > > > > > + case VALUE: > > > > > > + break; > > > > > > + case PATH: > > > > > > + strscpy(enum_data->common.path, str_value, > > > > > > + sizeof(enum_data->common.path)); > > > > > > + break; > > > > > > + case IS_READONLY: > > > > > > + enum_data->common.is_readonly = int_value; > > > > > > + break; > > > > > > + case DISPLAY_IN_UI: > > > > > > + enum_data->common.display_in_ui = int_value; > > > > > > + break; > > > > > > + case REQUIRES_PHYSICAL_PRESENCE: > > > > > > + enum_data->common.requires_physical_presence = int_value; > > > > > > + break; > > > > > > + case SEQUENCE: > > > > > > + enum_data->common.sequence = int_value; > > > > > > + break; > > > > > > + case PREREQUISITES_SIZE: > > > > > > + enum_data->common.prerequisites_size = int_value; > > > > > > + if (int_value > MAX_PREREQUISITES_SIZE) > > > > > > + pr_warn("Prerequisites size value exceeded the maximum number of elements supported or data may be malformed\n"); > > > > > > + > > > > > > + /* > > > > > > + * This HACK is needed to keep the expected > > > > > > + * element list pointing to the right obj[elem].type > > > > > > + * when the size is zero. PREREQUISITES > > > > > > + * object is omitted by BIOS when the size is > > > > > > + * zero. > > > > > > + */ > > > > > > + if (int_value == 0) > > > > > > + eloc++; > > > > > > + break; > > > > > > + > > > > > > + case PREREQUISITES: > > > > > > + size = min_t(u32, enum_data->common.prerequisites_size, MAX_PREREQUISITES_SIZE); > > > > > > > > > > We cannot blindly truncate this to a maximum value. > > > > > The firmware reported an amount of elements it would return. > > > > > > > > > > If this value is to big than we can not just intpret the data as if it > > > > > was something the firmware did not return. > > > > > > > > > > An error needs to be reported to userspace. > > > > > A default value is not enough as userspace can not interpret this > > > > > properly. > > > > > > > > > > > > > It is ok to truncate prerequisite size to MAX_PREREQUISITES_SIZE. > > > > MAX_PREREQUISITES_SIZE is a value predefined by BIOS when the > > > > prerequisite values size is invalid ( > MAX_PREREQUISITES_SIZE) and/or > > > > the prerequisite data is corrupted. > > > > Neither PREREQUISITES nor PREREQUISITES_SIZE are reported to the > > > > userspace so there is no need to report a failure on data that is not > > > > exposed. One item that needs clarification is the fact that > > > > regardless if PREREQUISITES or PREREQUISITES_SIZE are invalid, that > > > > does not mean other values are invalid. It is for this reason, we > > > > need to continue to read all remaining packages. > > > > > > It may be that prerequisites are not reported to userspace. > > > But the following values are: > > > > > > security level, current value and possible values. > > > > > > And if prerequisites are garbage then those are now also garbage. > > > > This statement is not correct. Each attribute value is isolated from > > each other hence it only affects a single value and does not impact > > the following values such security level, current value and possible > > values > > Indeed, I stand corrected. > I guess the loop-based logic is still confusing me. > > > Here is a sample where the prerequisite_size is invalid but the > > prerequisites, security, string min value and string max value are > > correct. > > > > 8003.571287] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite_size 3145848 > > [ 8003.571287] String Prerequisites size value exceeded the maximum > > number of elements supported or data may be malformed > > > > [ 8003.571288] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[0] > > /Pci(0x1F,0x6)/MAC(3 > > [ 8003.571288] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[1] > > 24D33F453F,0x0)/IPv6(000 > > [ 8003.571289] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[2] > > :0000:0000:0000:0000:000 > > [ 8003.571290] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[3] > > :0000:0000,0x0,Static,00 > > [ 8003.571290] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[4] > > 0:0000:0000:0000:0000:00 > > [ 8003.571291] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[5] > > 0:0000:0000,0x40,0000:00 > > [ 8003.571291] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[6] > > 0:0000:0000:0000:0000:00 > > [ 8003.571292] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[7] > > 0:0000)\r\n\tPciRoot(0x0)/P > > [ 8003.571292] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[8] > > i(0x0,0x0)/IPv4(0.0.0.0,0x0,DHCP,0.0.0.0,0.0.0.0, > > [ 8003.571293] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[9] > > .0.0.0)\r\n\tPciRoot(0x0)/P > > [ 8003.571293] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[10] > > i(0x0,0x0)/IPv6(0000:0000:0000:0000:0000:0000:000 > > [ 8003.571294] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[11] > > :0000,0x0,Static,0000:00 > > [ 8003.571295] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[12] > > 0:0000:0000:0000:0000:00 > > [ 8003.571295] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[13] > > 0:0000,0x0,0000:0000:000 > > [ 8003.571296] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[14] > > :0000:0000:0000:0000:000 > > [ 8003.571296] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[15] ) > > [ 8003.571297] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[16] > > [ 8003.571297] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[17] > > [ 8003.571298] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[18] > > [ 8003.571298] Attribute: HP_Disk0MapForUefiBootOrder Prerequisite[19] > > > > [ 8003.571298] Attribute: HP_Disk0MapForUefiBootOrder Security 0 > > [ 8003.571299] Attribute: HP_Disk0MapForUefiBootOrder String Min Length 0 > > [ 8003.571299] Attribute: HP_Disk0MapForUefiBootOrder String Max Length 0 > > > > > > > > > > hp_populate_enumeration_package_data() always returns "0". > > > > Earlier in the code, failures reported for a particular attribute > > value were ignored because each value is independent from each other. > > It is up to the user space application to analyze the raw data read from BIOS. > > Please remember that this API will not only be used by HPs own userspace > component. > > Where are the rules for userspace documented to analyze the raw data and recognize > an error? > Looking at the kernel log is not enough, it is not an API. Completely agree. At this time, Linux Security components are under development and not published yet. The only linux component is the driver (hp bioscfg) at this time. Other published security components are under Windows. Both Linux and Windows drivers return the data from BIOS as is and either one can determine if the data is valid or not. I have an idea how the data available to the user can be saved and reported as an error when read by the userspace component from sysfs. This solution will not change the way data is read or return value is reported by hp_populate_enumeration_package_data(). Let me think about it and will get back to you. > > > > > > > > In earlier reviews, it was agreed to report a warning that reads > > > > > > > > /* Report a message and limit prerequisite size to maximum value */ > > > > pr_warn("Enum Prerequisites size value exceeded the maximum number of > > > > elements supported or data may be malformed\n"); > > > > > > > > See lines 370-374 > > > > > > > > > (Affects all attributes) > > > > > > > > > > > + for (reqs = 0; reqs < size; reqs++) { > > > > > > + if (elem >= enum_obj_count) { > > > > > > + pr_err("Error enum-objects package is too small\n"); > > > > > > + return -EINVAL; > > > > > > + } > > > > > > + > > > > > > + ret = hp_convert_hexstr_to_str(enum_obj[elem + reqs].string.pointer, > > > > > > + enum_obj[elem + reqs].string.length, > > > > > > + &str_value, &value_len); > > > > > > + > > > > > > + if (ret) > > > > > > + return -EINVAL; > > > > > > + > > > > > > + strscpy(enum_data->common.prerequisites[reqs], > > > > > > + str_value, > > > > > > + sizeof(enum_data->common.prerequisites[reqs])); > > > > > > + > > > > > > + kfree(str_value); > > > > > > + } > > > > > > + break; > > > > > > + > > > > > > + case SECURITY_LEVEL: > > > > > > + enum_data->common.security_level = int_value; > > > > > > + break; > > > > > > + > > > > > > + case ENUM_CURRENT_VALUE: > > > > > > + strscpy(enum_data->current_value, > > > > > > + str_value, sizeof(enum_data->current_value)); > > > > > > + break; > > > > > > + case ENUM_SIZE: > > > > > > + enum_data->possible_values_size = int_value; > > > > > > + if (int_value > MAX_VALUES_SIZE) > > > > > > + pr_warn("Possible number values size value exceeded the maximum number of elements supported or data may be malformed\n"); > > > > > > + > > > > > > + /* > > > > > > + * This HACK is needed to keep the expected > > > > > > + * element list pointing to the right obj[elem].type > > > > > > + * when the size is zero. POSSIBLE_VALUES > > > > > > + * object is omitted by BIOS when the size is zero. > > > > > > + */ > > > > > > + if (int_value == 0) > > > > > > + eloc++; > > > > > > + break; > > > > > > + > > > > > > + case ENUM_POSSIBLE_VALUES: > > > > > > + size = enum_data->possible_values_size; > > > > > > + > > > > > > + for (pos_values = 0; pos_values < size && pos_values < MAX_VALUES_SIZE; > > > > > > + pos_values++) { > > > > > > + if (elem >= enum_obj_count) { > > > > > > + pr_err("Error enum-objects package is too small\n"); > > > > > > + return -EINVAL; > > > > > > + } > > > > > > + > > > > > > + ret = hp_convert_hexstr_to_str(enum_obj[elem + pos_values].string.pointer, > > > > > > + enum_obj[elem + pos_values].string.length, > > > > > > + &str_value, &value_len); > > > > > > + > > > > > > + if (ret) > > > > > > + return -EINVAL; > > > > > > + > > > > > > + /* > > > > > > + * ignore strings when possible values size > > > > > > + * is greater than MAX_VALUES_SIZE > > > > > > + */ > > > > > > + if (size < MAX_VALUES_SIZE) > > > > > > + strscpy(enum_data->possible_values[pos_values], > > > > > > + str_value, > > > > > > + sizeof(enum_data->possible_values[pos_values])); > > > > > > + } > > > > > > + break; > > > > > > + default: > > > > > > + pr_warn("Invalid element: %d found in Enumeration attribute or data may be malformed\n", elem); > > > > > > + break; > > > > > > + } > > > > > > + > > > > > > + kfree(str_value); > > > > > > + } > > > > > > + > > > > > > +exit_enumeration_package: > > > > > > + kfree(str_value); > > > > > > + return 0; > > > > > > +} > > > > > > + > > > > > > +/** > > > > > > + * hp_populate_enumeration_package_data() - > > > > > > + * Populate all properties of an instance under enumeration attribute > > > > > > + * > > > > > > + * @enum_obj: ACPI object with enumeration data > > > > > > + * @instance_id: The instance to enumerate > > > > > > + * @attr_name_kobj: The parent kernel object > > > > > > + */ > > > > > > +int hp_populate_enumeration_package_data(union acpi_object *enum_obj, > > > > > > + int instance_id, > > > > > > + struct kobject *attr_name_kobj) > > > > > > +{ > > > > > > + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; > > > > > > + > > > > > > + enum_data->attr_name_kobj = attr_name_kobj; > > > > > > + > > > > > > + hp_populate_enumeration_elements_from_package(enum_obj, > > > > > > + enum_obj->package.count, > > > > > > + instance_id); > > > > > > + hp_update_attribute_permissions(enum_data->common.is_readonly, > > > > > > + &enumeration_current_val); > > > > > > + /* > > > > > > + * Several attributes have names such "MONDAY". Friendly > > > > > > + * user nane is generated to make the name more descriptive > > > > > > + */ > > > > > > + hp_friendly_user_name_update(enum_data->common.path, > > > > > > + attr_name_kobj->name, > > > > > > + enum_data->common.display_name, > > > > > > + sizeof(enum_data->common.display_name)); > > > > > > + return sysfs_create_group(attr_name_kobj, &enumeration_attr_group); > > > > > > +} > > > > > > + > > > > > > +static int hp_populate_enumeration_elements_from_buffer(u8 *buffer_ptr, u32 *buffer_size, > > > > > > + int instance_id) > > > > > > +{ > > > > > > + int reqs; > > > > > > + int values; > > > > > > + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; > > > > > > + > > > > > > + /* > > > > > > + * In earlier implementation, reported errors were ignored > > > > > > + * causing the data to remain uninitialized. It is for this > > > > > > + * reason functions may return an error and no validation > > > > > > + * takes place. > > > > > > + */ > > > > > > > > > > Where is this error returned? > > > > > > > > functions such hp_get_string_from_buffer, hp_get_integer_from_buffer > > > > > > But the errors returned from those functions are just thrown away, no? > > > > Earlier in the code, failures reported for a particular attribute > > value were ignored because each value is independent from each other. > > It is for this reason, we are throwing away any errors returned from > > those functions. > > > > > > > > > > > > > + > > > > > > + // VALUE: > > > > > > + hp_get_string_from_buffer(&buffer_ptr, buffer_size, enum_data->current_value, > > > > > > + sizeof(enum_data->current_value)); > > > > > > + > > > > > > + // PATH: > > > > > > + hp_get_string_from_buffer(&buffer_ptr, buffer_size, enum_data->common.path, > > > > > > + sizeof(enum_data->common.path)); > > > > > > + > > > > > > + // IS_READONLY: > > > > > > + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, > > > > > > + &enum_data->common.is_readonly); > > > > > > + > > > > > > + //DISPLAY_IN_UI: > > > > > > + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, > > > > > > + &enum_data->common.display_in_ui); > > > > > > + > > > > > > + // REQUIRES_PHYSICAL_PRESENCE: > > > > > > + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, > > > > > > + &enum_data->common.requires_physical_presence); > > > > > > + > > > > > > + // SEQUENCE: > > > > > > + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, > > > > > > + &enum_data->common.sequence); > > > > > > + > > > > > > + // PREREQUISITES_SIZE: > > > > > > + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, > > > > > > + &enum_data->common.prerequisites_size); > > > > > > + > > > > > > + if (enum_data->common.prerequisites_size > MAX_PREREQUISITES_SIZE) { > > > > > > + /* Report a message and limit prerequisite size to maximum value */ > > > > > > + pr_warn("Enum Prerequisites size value exceeded the maximum number of elements supported or data may be malformed\n"); > > > > > > + enum_data->common.prerequisites_size = MAX_PREREQUISITES_SIZE; > > > > > > + } > > > > > > + > > > > > > + // PREREQUISITES: > > > > > > + for (reqs = 0; reqs < enum_data->common.prerequisites_size; reqs++) > > > > > > + hp_get_string_from_buffer(&buffer_ptr, buffer_size, > > > > > > + enum_data->common.prerequisites[reqs], > > > > > > + sizeof(enum_data->common.prerequisites[reqs])); > > > > > > + > > > > > > + // SECURITY_LEVEL: > > > > > > + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, > > > > > > + &enum_data->common.security_level); > > > > > > > > > > The reading of all the common elemtns can be extracted into a helper > > > > > and reused from all the attributes. > > > > > > > > Is extracting all common elements into a helper routine absolutely > > > > necessary now or can it be refactored after driver is accepted? > > > > > > It's not necessary. > > > > Thank you > > > > > > > > > > > > > > + > > > > > > + // ENUM_CURRENT_VALUE: > > > > > > + hp_get_string_from_buffer(&buffer_ptr, buffer_size, > > > > > > + enum_data->current_value, > > > > > > + sizeof(enum_data->current_value)); > > > > > > + // ENUM_SIZE: > > > > > > + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, > > > > > > + &enum_data->possible_values_size); > > > > > > + > > > > > > + if (enum_data->possible_values_size > MAX_VALUES_SIZE) { > > > > > > + /* Report a message and limit possible values size to maximum value */ > > > > > > + pr_warn("Enum Possible size value exceeded the maximum number of elements supported or data may be malformed\n"); > > > > > > + enum_data->possible_values_size = MAX_VALUES_SIZE; > > > > > > + } > > > > > > + > > > > > > + // ENUM_POSSIBLE_VALUES: > > > > > > + > > > > > > + for (values = 0; values < enum_data->possible_values_size; values++) > > > > > > + hp_get_string_from_buffer(&buffer_ptr, buffer_size, > > > > > > + enum_data->possible_values[values], > > > > > > + sizeof(enum_data->possible_values[values])); > > > > > > + > > > > > > + return 0; > > > > > > +} > > > > > > + > > > > > > +/** > > > > > > + * hp_populate_enumeration_buffer_data() - > > > > > > + * Populate all properties of an instance under enumeration attribute > > > > > > + * > > > > > > + * @buffer_ptr: Buffer pointer > > > > > > + * @buffer_size: Buffer size > > > > > > + * @instance_id: The instance to enumerate > > > > > > + * @attr_name_kobj: The parent kernel object > > > > > > + */ > > > > > > +int hp_populate_enumeration_buffer_data(u8 *buffer_ptr, u32 *buffer_size, > > > > > > + int instance_id, > > > > > > + struct kobject *attr_name_kobj) > > > > > > +{ > > > > > > + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; > > > > > > + > > > > > > + enum_data->attr_name_kobj = attr_name_kobj; > > > > > > + > > > > > > + /* Populate enumeration elements */ > > > > > > + hp_populate_enumeration_elements_from_buffer(buffer_ptr, buffer_size, instance_id); > > > > > > + > > > > > > + hp_update_attribute_permissions(enum_data->common.is_readonly, > > > > > > + &enumeration_current_val); > > > > > > + /* > > > > > > + * Several attributes have names such "MONDAY". A Friendlier > > > > > > + * user nane is generated to make the name more descriptive > > > > > > + */ > > > > > > + hp_friendly_user_name_update(enum_data->common.path, > > > > > > + attr_name_kobj->name, > > > > > > + enum_data->common.display_name, > > > > > > + sizeof(enum_data->common.display_name)); > > > > > > + > > > > > > + return sysfs_create_group(attr_name_kobj, &enumeration_attr_group); > > > > > > +} > > > > > > + > > > > > > +/** > > > > > > + * hp_exit_enumeration_attributes() - Clear all attribute data > > > > > > + * > > > > > > + * Clears all data allocated for this group of attributes > > > > > > + */ > > > > > > +void hp_exit_enumeration_attributes(void) > > > > > > +{ > > > > > > + int instance_id; > > > > > > + > > > > > > + for (instance_id = 0; instance_id < bioscfg_drv.enumeration_instances_count; > > > > > > + instance_id++) { > > > > > > + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; > > > > > > + struct kobject *attr_name_kobj = enum_data->attr_name_kobj; > > > > > > + > > > > > > + if (attr_name_kobj) > > > > > > + sysfs_remove_group(attr_name_kobj, &enumeration_attr_group); > > > > > > + } > > > > > > + bioscfg_drv.enumeration_instances_count = 0; > > > > > > + > > > > > > + kfree(bioscfg_drv.enumeration_data); > > > > > > + bioscfg_drv.enumeration_data = NULL; > > > > > > +} > > > > > > -- > > > > > > 2.34.1 > > > > > >
diff --git a/drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c b/drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c new file mode 100644 index 000000000000..80842835606d --- /dev/null +++ b/drivers/platform/x86/hp/hp-bioscfg/enum-attributes.c @@ -0,0 +1,465 @@ +// SPDX-License-Identifier: GPL-2.0 +/* + * Functions corresponding to enumeration type attributes under + * BIOS Enumeration GUID for use with hp-bioscfg driver. + * + * Copyright (c) 2022 HP Development Company, L.P. + */ + +#include "bioscfg.h" + +GET_INSTANCE_ID(enumeration); + +static ssize_t current_value_show(struct kobject *kobj, struct kobj_attribute *attr, char *buf) +{ + int instance_id = get_enumeration_instance_id(kobj); + + if (instance_id < 0) + return -EIO; + + return sysfs_emit(buf, "%s\n", + bioscfg_drv.enumeration_data[instance_id].current_value); +} + +/** + * validate_enumeration_input() - + * Validate input of current_value against possible values + * + * @instance_id: The instance on which input is validated + * @buf: Input value + */ +static int validate_enumeration_input(int instance_id, const char *buf) +{ + int i; + int found = 0; + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; + + /* Is it a read only attribute */ + if (enum_data->common.is_readonly) + return -EIO; + + for (i = 0; i < enum_data->possible_values_size && !found; i++) + if (!strcmp(enum_data->possible_values[i], buf)) + found = 1; + + if (!found) + return -EINVAL; + + return 0; +} + +static void update_enumeration_value(int instance_id, char *attr_value) +{ + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; + + strscpy(enum_data->current_value, + attr_value, + sizeof(enum_data->current_value)); +} + +ATTRIBUTE_S_COMMON_PROPERTY_SHOW(display_name, enumeration); +static struct kobj_attribute enumeration_display_name = + __ATTR_RO(display_name); + +ATTRIBUTE_PROPERTY_STORE(current_value, enumeration); +static struct kobj_attribute enumeration_current_val = + __ATTR_RW(current_value); + +ATTRIBUTE_VALUES_PROPERTY_SHOW(possible_values, enumeration, SEMICOLON_SEP); +static struct kobj_attribute enumeration_poss_val = + __ATTR_RO(possible_values); + +static ssize_t type_show(struct kobject *kobj, struct kobj_attribute *attr, + char *buf) +{ + return sysfs_emit(buf, "enumeration\n"); +} + +static struct kobj_attribute enumeration_type = + __ATTR_RO(type); + +static struct kobj_attribute common_display_langcode = + __ATTR_RO(display_name_language_code); + +static struct attribute *enumeration_attrs[] = { + &common_display_langcode.attr, + &enumeration_display_name.attr, + &enumeration_current_val.attr, + &enumeration_poss_val.attr, + &enumeration_type.attr, + NULL +}; + +static const struct attribute_group enumeration_attr_group = { + .attrs = enumeration_attrs, +}; + +int hp_alloc_enumeration_data(void) +{ + bioscfg_drv.enumeration_instances_count = + hp_get_instance_count(HP_WMI_BIOS_ENUMERATION_GUID); + + bioscfg_drv.enumeration_data = kcalloc(bioscfg_drv.enumeration_instances_count, + sizeof(*bioscfg_drv.enumeration_data), GFP_KERNEL); + if (!bioscfg_drv.enumeration_data) { + bioscfg_drv.enumeration_instances_count = 0; + return -ENOMEM; + } + return 0; +} + +/* Expected Values types associated with each element */ +static const acpi_object_type expected_enum_types[] = { + [NAME] = ACPI_TYPE_STRING, + [VALUE] = ACPI_TYPE_STRING, + [PATH] = ACPI_TYPE_STRING, + [IS_READONLY] = ACPI_TYPE_INTEGER, + [DISPLAY_IN_UI] = ACPI_TYPE_INTEGER, + [REQUIRES_PHYSICAL_PRESENCE] = ACPI_TYPE_INTEGER, + [SEQUENCE] = ACPI_TYPE_INTEGER, + [PREREQUISITES_SIZE] = ACPI_TYPE_INTEGER, + [PREREQUISITES] = ACPI_TYPE_STRING, + [SECURITY_LEVEL] = ACPI_TYPE_INTEGER, + [ENUM_CURRENT_VALUE] = ACPI_TYPE_STRING, + [ENUM_SIZE] = ACPI_TYPE_INTEGER, + [ENUM_POSSIBLE_VALUES] = ACPI_TYPE_STRING, +}; + +static int hp_populate_enumeration_elements_from_package(union acpi_object *enum_obj, + int enum_obj_count, + int instance_id) +{ + char *str_value = NULL; + int value_len; + u32 size = 0; + u32 int_value; + int elem = 0; + int reqs; + int pos_values; + int ret; + int eloc; + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; + + for (elem = 1, eloc = 1; elem < enum_obj_count; elem++, eloc++) { + /* ONLY look at the first ENUM_ELEM_CNT elements */ + if (eloc == ENUM_ELEM_CNT) + goto exit_enumeration_package; + + switch (enum_obj[elem].type) { + case ACPI_TYPE_STRING: + if (PREREQUISITES != elem && ENUM_POSSIBLE_VALUES != elem) { + ret = hp_convert_hexstr_to_str(enum_obj[elem].string.pointer, + enum_obj[elem].string.length, + &str_value, &value_len); + if (ret) + return -EINVAL; + } + break; + case ACPI_TYPE_INTEGER: + int_value = (u32)enum_obj[elem].integer.value; + break; + default: + pr_warn("Unsupported object type [%d]\n", enum_obj[elem].type); + continue; + } + + /* Check that both expected and read object type match */ + if (expected_enum_types[eloc] != enum_obj[elem].type) { + pr_err("Error expected type %d for elem %d, but got type %d instead\n", + expected_enum_types[eloc], elem, enum_obj[elem].type); + return -EIO; + } + + /* Assign appropriate element value to corresponding field */ + switch (eloc) { + case NAME: + case VALUE: + break; + case PATH: + strscpy(enum_data->common.path, str_value, + sizeof(enum_data->common.path)); + break; + case IS_READONLY: + enum_data->common.is_readonly = int_value; + break; + case DISPLAY_IN_UI: + enum_data->common.display_in_ui = int_value; + break; + case REQUIRES_PHYSICAL_PRESENCE: + enum_data->common.requires_physical_presence = int_value; + break; + case SEQUENCE: + enum_data->common.sequence = int_value; + break; + case PREREQUISITES_SIZE: + enum_data->common.prerequisites_size = int_value; + if (int_value > MAX_PREREQUISITES_SIZE) + pr_warn("Prerequisites size value exceeded the maximum number of elements supported or data may be malformed\n"); + + /* + * This HACK is needed to keep the expected + * element list pointing to the right obj[elem].type + * when the size is zero. PREREQUISITES + * object is omitted by BIOS when the size is + * zero. + */ + if (int_value == 0) + eloc++; + break; + + case PREREQUISITES: + size = min_t(u32, enum_data->common.prerequisites_size, MAX_PREREQUISITES_SIZE); + for (reqs = 0; reqs < size; reqs++) { + if (elem >= enum_obj_count) { + pr_err("Error enum-objects package is too small\n"); + return -EINVAL; + } + + ret = hp_convert_hexstr_to_str(enum_obj[elem + reqs].string.pointer, + enum_obj[elem + reqs].string.length, + &str_value, &value_len); + + if (ret) + return -EINVAL; + + strscpy(enum_data->common.prerequisites[reqs], + str_value, + sizeof(enum_data->common.prerequisites[reqs])); + + kfree(str_value); + } + break; + + case SECURITY_LEVEL: + enum_data->common.security_level = int_value; + break; + + case ENUM_CURRENT_VALUE: + strscpy(enum_data->current_value, + str_value, sizeof(enum_data->current_value)); + break; + case ENUM_SIZE: + enum_data->possible_values_size = int_value; + if (int_value > MAX_VALUES_SIZE) + pr_warn("Possible number values size value exceeded the maximum number of elements supported or data may be malformed\n"); + + /* + * This HACK is needed to keep the expected + * element list pointing to the right obj[elem].type + * when the size is zero. POSSIBLE_VALUES + * object is omitted by BIOS when the size is zero. + */ + if (int_value == 0) + eloc++; + break; + + case ENUM_POSSIBLE_VALUES: + size = enum_data->possible_values_size; + + for (pos_values = 0; pos_values < size && pos_values < MAX_VALUES_SIZE; + pos_values++) { + if (elem >= enum_obj_count) { + pr_err("Error enum-objects package is too small\n"); + return -EINVAL; + } + + ret = hp_convert_hexstr_to_str(enum_obj[elem + pos_values].string.pointer, + enum_obj[elem + pos_values].string.length, + &str_value, &value_len); + + if (ret) + return -EINVAL; + + /* + * ignore strings when possible values size + * is greater than MAX_VALUES_SIZE + */ + if (size < MAX_VALUES_SIZE) + strscpy(enum_data->possible_values[pos_values], + str_value, + sizeof(enum_data->possible_values[pos_values])); + } + break; + default: + pr_warn("Invalid element: %d found in Enumeration attribute or data may be malformed\n", elem); + break; + } + + kfree(str_value); + } + +exit_enumeration_package: + kfree(str_value); + return 0; +} + +/** + * hp_populate_enumeration_package_data() - + * Populate all properties of an instance under enumeration attribute + * + * @enum_obj: ACPI object with enumeration data + * @instance_id: The instance to enumerate + * @attr_name_kobj: The parent kernel object + */ +int hp_populate_enumeration_package_data(union acpi_object *enum_obj, + int instance_id, + struct kobject *attr_name_kobj) +{ + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; + + enum_data->attr_name_kobj = attr_name_kobj; + + hp_populate_enumeration_elements_from_package(enum_obj, + enum_obj->package.count, + instance_id); + hp_update_attribute_permissions(enum_data->common.is_readonly, + &enumeration_current_val); + /* + * Several attributes have names such "MONDAY". Friendly + * user nane is generated to make the name more descriptive + */ + hp_friendly_user_name_update(enum_data->common.path, + attr_name_kobj->name, + enum_data->common.display_name, + sizeof(enum_data->common.display_name)); + return sysfs_create_group(attr_name_kobj, &enumeration_attr_group); +} + +static int hp_populate_enumeration_elements_from_buffer(u8 *buffer_ptr, u32 *buffer_size, + int instance_id) +{ + int reqs; + int values; + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; + + /* + * In earlier implementation, reported errors were ignored + * causing the data to remain uninitialized. It is for this + * reason functions may return an error and no validation + * takes place. + */ + + // VALUE: + hp_get_string_from_buffer(&buffer_ptr, buffer_size, enum_data->current_value, + sizeof(enum_data->current_value)); + + // PATH: + hp_get_string_from_buffer(&buffer_ptr, buffer_size, enum_data->common.path, + sizeof(enum_data->common.path)); + + // IS_READONLY: + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, + &enum_data->common.is_readonly); + + //DISPLAY_IN_UI: + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, + &enum_data->common.display_in_ui); + + // REQUIRES_PHYSICAL_PRESENCE: + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, + &enum_data->common.requires_physical_presence); + + // SEQUENCE: + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, + &enum_data->common.sequence); + + // PREREQUISITES_SIZE: + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, + &enum_data->common.prerequisites_size); + + if (enum_data->common.prerequisites_size > MAX_PREREQUISITES_SIZE) { + /* Report a message and limit prerequisite size to maximum value */ + pr_warn("Enum Prerequisites size value exceeded the maximum number of elements supported or data may be malformed\n"); + enum_data->common.prerequisites_size = MAX_PREREQUISITES_SIZE; + } + + // PREREQUISITES: + for (reqs = 0; reqs < enum_data->common.prerequisites_size; reqs++) + hp_get_string_from_buffer(&buffer_ptr, buffer_size, + enum_data->common.prerequisites[reqs], + sizeof(enum_data->common.prerequisites[reqs])); + + // SECURITY_LEVEL: + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, + &enum_data->common.security_level); + + // ENUM_CURRENT_VALUE: + hp_get_string_from_buffer(&buffer_ptr, buffer_size, + enum_data->current_value, + sizeof(enum_data->current_value)); + // ENUM_SIZE: + hp_get_integer_from_buffer(&buffer_ptr, buffer_size, + &enum_data->possible_values_size); + + if (enum_data->possible_values_size > MAX_VALUES_SIZE) { + /* Report a message and limit possible values size to maximum value */ + pr_warn("Enum Possible size value exceeded the maximum number of elements supported or data may be malformed\n"); + enum_data->possible_values_size = MAX_VALUES_SIZE; + } + + // ENUM_POSSIBLE_VALUES: + + for (values = 0; values < enum_data->possible_values_size; values++) + hp_get_string_from_buffer(&buffer_ptr, buffer_size, + enum_data->possible_values[values], + sizeof(enum_data->possible_values[values])); + + return 0; +} + +/** + * hp_populate_enumeration_buffer_data() - + * Populate all properties of an instance under enumeration attribute + * + * @buffer_ptr: Buffer pointer + * @buffer_size: Buffer size + * @instance_id: The instance to enumerate + * @attr_name_kobj: The parent kernel object + */ +int hp_populate_enumeration_buffer_data(u8 *buffer_ptr, u32 *buffer_size, + int instance_id, + struct kobject *attr_name_kobj) +{ + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; + + enum_data->attr_name_kobj = attr_name_kobj; + + /* Populate enumeration elements */ + hp_populate_enumeration_elements_from_buffer(buffer_ptr, buffer_size, instance_id); + + hp_update_attribute_permissions(enum_data->common.is_readonly, + &enumeration_current_val); + /* + * Several attributes have names such "MONDAY". A Friendlier + * user nane is generated to make the name more descriptive + */ + hp_friendly_user_name_update(enum_data->common.path, + attr_name_kobj->name, + enum_data->common.display_name, + sizeof(enum_data->common.display_name)); + + return sysfs_create_group(attr_name_kobj, &enumeration_attr_group); +} + +/** + * hp_exit_enumeration_attributes() - Clear all attribute data + * + * Clears all data allocated for this group of attributes + */ +void hp_exit_enumeration_attributes(void) +{ + int instance_id; + + for (instance_id = 0; instance_id < bioscfg_drv.enumeration_instances_count; + instance_id++) { + struct enumeration_data *enum_data = &bioscfg_drv.enumeration_data[instance_id]; + struct kobject *attr_name_kobj = enum_data->attr_name_kobj; + + if (attr_name_kobj) + sysfs_remove_group(attr_name_kobj, &enumeration_attr_group); + } + bioscfg_drv.enumeration_instances_count = 0; + + kfree(bioscfg_drv.enumeration_data); + bioscfg_drv.enumeration_data = NULL; +}