From patchwork Thu Sep 21 13:57:12 2017 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: "Limonciello, Mario" X-Patchwork-Id: 9964011 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id 035366020C for ; Thu, 21 Sep 2017 13:59:32 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id F351F29031 for ; Thu, 21 Sep 2017 13:59:31 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id E83EA29085; Thu, 21 Sep 2017 13:59:31 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.8 required=2.0 tests=BAYES_00,DKIM_SIGNED, RCVD_IN_DNSWL_HI,T_DKIM_INVALID autolearn=unavailable version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 697982906B for ; Thu, 21 Sep 2017 13:59:31 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751906AbdIUN6v (ORCPT ); Thu, 21 Sep 2017 09:58:51 -0400 Received: from esa3.dell-outbound.iphmx.com ([68.232.153.94]:51150 "EHLO esa3.dell-outbound.iphmx.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751881AbdIUN5a (ORCPT ); Thu, 21 Sep 2017 09:57:30 -0400 DKIM-Signature: v=1; a=rsa-sha256; c=simple/simple; d=dell.com; i=@dell.com; q=dns/txt; s=smtpout; t=1506002163; x=1537538163; h=from:to:cc:subject:date:message-id; bh=hOTaQ5Zf11x0FEqybCRs8R5iFuavliE1BAFmH0qBlOg=; b=aJxU1I4Zh9PoJgbB42oZB+wxxFm9i5y3fydWYWc86rUDzHY+B26vKJt7 2+XCyH+zG47RcwEGP0DGVPu+/DfAV/pSxWNASMMpoYmRDvEJOQsGA3ITn 9C69oJntrPwxliaH1G6wZxdiHk5G++RMZ4yKIv0PlpB6VSxN+0TDktaMf 0=; Received: from esa5.dell-outbound2.iphmx.com ([68.232.153.203]) by esa3.dell-outbound.iphmx.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 21 Sep 2017 08:56:03 -0500 Received: from ausxipps310.us.dell.com ([143.166.148.211]) by esa5.dell-outbound2.iphmx.com with ESMTP/TLS/DHE-RSA-AES256-GCM-SHA384; 21 Sep 2017 19:49:29 +0600 X-LoopCount0: from 10.208.86.39 X-IronPort-AV: E=Sophos;i="5.42,425,1500958800"; d="scan'208";a="64188948" X-DLP: DLP_GlobalPCIDSS From: Mario Limonciello To: dvhart@infradead.org Cc: LKML , platform-driver-x86@vger.kernel.org, quasisec@google.com, pali.rohar@gmail.com, Mario Limonciello Subject: [PATCH 07/12] platform/x86: dell-wmi-smbios: Use Dell WMI descriptor check Date: Thu, 21 Sep 2017 08:57:12 -0500 Message-Id: <1001812b63d73bf3ccd5ea6c76604cae0fa1525a.1505999739.git.mario.limonciello@dell.com> X-Mailer: git-send-email 2.7.4 In-Reply-To: References: In-Reply-To: References: Sender: platform-driver-x86-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: platform-driver-x86@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP The Dell WMI descriptor check is used as an indication that WMI calls are safe to run both when used with the notification ASL/GUID pair as well as the SMBIOS calling ASL/GUID pair. As some code in dell-wmi-smbios is already a prerequisite for dell-wmi, move the code for performing the descriptor check into dell-wmi-smbios and let both drivers use it from there. Signed-off-by: Mario Limonciello --- drivers/platform/x86/dell-wmi-smbios.c | 78 ++++++++++++++++++++++++++++++++++ drivers/platform/x86/dell-wmi-smbios.h | 3 ++ drivers/platform/x86/dell-wmi.c | 75 +------------------------------- 3 files changed, 82 insertions(+), 74 deletions(-) diff --git a/drivers/platform/x86/dell-wmi-smbios.c b/drivers/platform/x86/dell-wmi-smbios.c index c3701fdadf7b..9deb851ff517 100644 --- a/drivers/platform/x86/dell-wmi-smbios.c +++ b/drivers/platform/x86/dell-wmi-smbios.c @@ -24,6 +24,7 @@ #include "dell-wmi-smbios.h" #define DELL_WMI_SMBIOS_GUID "A80593CE-A997-11DA-B012-B622A1EF5492" +#define DELL_DESCRIPTOR_GUID "8D9DDCBC-A997-11DA-B012-B622A1EF5492" struct calling_interface_structure { struct dmi_header header; @@ -217,8 +218,81 @@ static const struct attribute_group smbios_attribute_group = { .attrs = smbios_attrs, }; +/* + * Descriptor buffer is 128 byte long and contains: + * + * Name Offset Length Value + * Vendor Signature 0 4 "DELL" + * Object Signature 4 4 " WMI" + * WMI Interface Version 8 4 + * WMI buffer length 12 4 4096 + */ +int dell_wmi_check_descriptor_buffer(struct wmi_device *wdev, u32 *version) +{ + union acpi_object *obj = NULL; + struct wmi_device *desc_dev; + u32 *desc_buffer; + int ret; + + desc_dev = wmidev_get_other_guid(wdev, DELL_DESCRIPTOR_GUID); + if (!desc_dev) { + dev_err(&wdev->dev, "Dell WMI descriptor does not exist\n"); + return -ENODEV; + } + + obj = wmidev_block_query(desc_dev, 0); + if (!obj) { + dev_err(&wdev->dev, "failed to read Dell WMI descriptor\n"); + ret = -EIO; + goto out; + } + + if (obj->type != ACPI_TYPE_BUFFER) { + dev_err(&wdev->dev, "Dell descriptor has wrong type\n"); + ret = -EINVAL; + goto out; + } + + if (obj->buffer.length != 128) { + dev_err(&wdev->dev, + "Dell descriptor buffer has invalid length (%d)\n", + obj->buffer.length); + if (obj->buffer.length < 16) { + ret = -EINVAL; + goto out; + } + } + + desc_buffer = (u32 *)obj->buffer.pointer; + + if (desc_buffer[0] != 0x4C4C4544 && desc_buffer[1] != 0x494D5720) + dev_warn(&wdev->dev, "Dell descriptor buffer has invalid signature (%*ph)\n", + 8, desc_buffer); + + if (desc_buffer[2] != 0 && desc_buffer[2] != 1) + dev_warn(&wdev->dev, "Dell descriptor buffer has unknown version (%d)\n", + desc_buffer[2]); + + if (desc_buffer[3] != 4096) + dev_warn(&wdev->dev, "Dell descriptor buffer has invalid buffer length (%d)\n", + desc_buffer[3]); + + *version = desc_buffer[2]; + ret = 0; + + dev_info(&wdev->dev, "Detected Dell WMI interface version %u\n", + *version); + +out: + kfree(obj); + put_device(&desc_dev->dev); + return ret; +} +EXPORT_SYMBOL_GPL(dell_wmi_check_descriptor_buffer); + static int dell_wmi_smbios_probe(struct wmi_device *wdev) { + u32 interface_version; int ret; dmi_walk(find_tokens, NULL); @@ -228,6 +302,10 @@ static int dell_wmi_smbios_probe(struct wmi_device *wdev) return -ENODEV; } + ret = dell_wmi_check_descriptor_buffer(wdev, &interface_version); + if (ret) + return ret; + buffer = (void *)__get_free_page(GFP_KERNEL); if (!buffer) { ret = -ENOMEM; diff --git a/drivers/platform/x86/dell-wmi-smbios.h b/drivers/platform/x86/dell-wmi-smbios.h index e6e9990bb2b7..0521ec5d437b 100644 --- a/drivers/platform/x86/dell-wmi-smbios.h +++ b/drivers/platform/x86/dell-wmi-smbios.h @@ -17,6 +17,8 @@ #ifndef _DELL_WMI_SMBIOS_H_ #define _DELL_WMI_SMBIOS_H_ +#include + struct notifier_block; struct calling_interface_buffer { @@ -54,5 +56,6 @@ enum dell_laptop_notifier_actions { int dell_laptop_register_notifier(struct notifier_block *nb); int dell_laptop_unregister_notifier(struct notifier_block *nb); void dell_laptop_call_notifier(unsigned long action, void *data); +int dell_wmi_check_descriptor_buffer(struct wmi_device *wdev, u32 *version); #endif diff --git a/drivers/platform/x86/dell-wmi.c b/drivers/platform/x86/dell-wmi.c index e8b4d412eabc..e7011792127f 100644 --- a/drivers/platform/x86/dell-wmi.c +++ b/drivers/platform/x86/dell-wmi.c @@ -46,7 +46,6 @@ MODULE_DESCRIPTION("Dell laptop WMI hotkeys driver"); MODULE_LICENSE("GPL"); #define DELL_EVENT_GUID "9DBB5994-A997-11DA-B012-B622A1EF5492" -#define DELL_DESCRIPTOR_GUID "8D9DDCBC-A997-11DA-B012-B622A1EF5492" static bool wmi_requires_smbios_request; @@ -617,78 +616,6 @@ static void dell_wmi_input_destroy(struct wmi_device *wdev) input_unregister_device(priv->input_dev); } -/* - * Descriptor buffer is 128 byte long and contains: - * - * Name Offset Length Value - * Vendor Signature 0 4 "DELL" - * Object Signature 4 4 " WMI" - * WMI Interface Version 8 4 - * WMI buffer length 12 4 4096 - */ -static int dell_wmi_check_descriptor_buffer(struct wmi_device *wdev) -{ - struct dell_wmi_priv *priv = dev_get_drvdata(&wdev->dev); - union acpi_object *obj = NULL; - struct wmi_device *desc_dev; - u32 *buffer; - int ret; - - desc_dev = wmidev_get_other_guid(wdev, DELL_DESCRIPTOR_GUID); - if (!desc_dev) { - dev_err(&wdev->dev, "Dell WMI descriptor does not exist\n"); - return -ENODEV; - } - - obj = wmidev_block_query(desc_dev, 0); - if (!obj) { - dev_err(&wdev->dev, "failed to read Dell WMI descriptor\n"); - ret = -EIO; - goto out; - } - - if (obj->type != ACPI_TYPE_BUFFER) { - dev_err(&wdev->dev, "Dell descriptor has wrong type\n"); - ret = -EINVAL; - goto out; - } - - if (obj->buffer.length != 128) { - dev_err(&wdev->dev, - "Dell descriptor buffer has invalid length (%d)\n", - obj->buffer.length); - if (obj->buffer.length < 16) { - ret = -EINVAL; - goto out; - } - } - - buffer = (u32 *)obj->buffer.pointer; - - if (buffer[0] != 0x4C4C4544 && buffer[1] != 0x494D5720) - dev_warn(&wdev->dev, "Dell descriptor buffer has invalid signature (%*ph)\n", - 8, buffer); - - if (buffer[2] != 0 && buffer[2] != 1) - dev_warn(&wdev->dev, "Dell descriptor buffer has unknown version (%d)\n", - buffer[2]); - - if (buffer[3] != 4096) - dev_warn(&wdev->dev, "Dell descriptor buffer has invalid buffer length (%d)\n", - buffer[3]); - - priv->interface_version = buffer[2]; - ret = 0; - - dev_info(&wdev->dev, "Detected Dell WMI interface version %u\n", - priv->interface_version); - -out: - kfree(obj); - put_device(&desc_dev->dev); - return ret; -} - /* * According to Dell SMBIOS documentation: * @@ -732,7 +659,7 @@ static int dell_wmi_probe(struct wmi_device *wdev) return -ENOMEM; dev_set_drvdata(&wdev->dev, priv); - err = dell_wmi_check_descriptor_buffer(wdev); + err = dell_wmi_check_descriptor_buffer(wdev, &priv->interface_version); if (err) return err;