2013-02-08 16:37:06 +01:00
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/*
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* Originally from efivars.c,
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*
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* Copyright (C) 2001,2003,2004 Dell <Matt_Domsch@dell.com>
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* Copyright (C) 2004 Intel Corporation <matthew.e.tolentino@intel.com>
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*
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* This code takes all variables accessible from EFI runtime and
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* exports them via sysfs
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*
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* This program is free software; you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation; either version 2 of the License, or
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* (at your option) any later version.
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*
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* This program is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with this program; if not, write to the Free Software
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* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
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*
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* Changelog:
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*
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* 17 May 2004 - Matt Domsch <Matt_Domsch@dell.com>
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* remove check for efi_enabled in exit
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* add MODULE_VERSION
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*
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* 26 Apr 2004 - Matt Domsch <Matt_Domsch@dell.com>
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* minor bug fixes
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*
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* 21 Apr 2004 - Matt Tolentino <matthew.e.tolentino@intel.com)
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* converted driver to export variable information via sysfs
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* and moved to drivers/firmware directory
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* bumped revision number to v0.07 to reflect conversion & move
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*
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* 10 Dec 2002 - Matt Domsch <Matt_Domsch@dell.com>
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* fix locking per Peter Chubb's findings
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*
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* 25 Mar 2002 - Matt Domsch <Matt_Domsch@dell.com>
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2014-12-18 16:02:17 +01:00
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* move uuid_unparse() to include/asm-ia64/efi.h:efi_guid_to_str()
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2013-02-08 16:37:06 +01:00
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*
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* 12 Feb 2002 - Matt Domsch <Matt_Domsch@dell.com>
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* use list_for_each_safe when deleting vars.
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* remove ifdef CONFIG_SMP around include <linux/smp.h>
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* v0.04 release to linux-ia64@linuxia64.org
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*
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* 20 April 2001 - Matt Domsch <Matt_Domsch@dell.com>
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* Moved vars from /proc/efi to /proc/efi/vars, and made
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* efi.c own the /proc/efi directory.
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* v0.03 release to linux-ia64@linuxia64.org
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*
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* 26 March 2001 - Matt Domsch <Matt_Domsch@dell.com>
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* At the request of Stephane, moved ownership of /proc/efi
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* to efi.c, and now efivars lives under /proc/efi/vars.
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*
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* 12 March 2001 - Matt Domsch <Matt_Domsch@dell.com>
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* Feedback received from Stephane Eranian incorporated.
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* efivar_write() checks copy_from_user() return value.
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* efivar_read/write() returns proper errno.
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* v0.02 release to linux-ia64@linuxia64.org
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*
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* 26 February 2001 - Matt Domsch <Matt_Domsch@dell.com>
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* v0.01 release to linux-ia64@linuxia64.org
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*/
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#include <linux/efi.h>
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#include <linux/module.h>
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2013-05-02 02:51:54 +02:00
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#include <linux/slab.h>
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2013-04-30 12:30:24 +02:00
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#include <linux/ucs2_string.h>
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2014-03-17 16:36:37 +01:00
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#include <linux/compat.h>
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2013-02-08 16:37:06 +01:00
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#define EFIVARS_VERSION "0.08"
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#define EFIVARS_DATE "2004-May-17"
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MODULE_AUTHOR("Matt Domsch <Matt_Domsch@Dell.com>");
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MODULE_DESCRIPTION("sysfs interface to EFI Variables");
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MODULE_LICENSE("GPL");
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MODULE_VERSION(EFIVARS_VERSION);
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2014-07-09 12:39:29 +02:00
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MODULE_ALIAS("platform:efivars");
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2013-02-08 16:37:06 +01:00
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LIST_HEAD(efivar_sysfs_list);
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EXPORT_SYMBOL_GPL(efivar_sysfs_list);
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static struct kset *efivars_kset;
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static struct bin_attribute *efivars_new_var;
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static struct bin_attribute *efivars_del_var;
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2014-03-17 16:36:37 +01:00
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struct compat_efi_variable {
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efi_char16_t VariableName[EFI_VAR_NAME_LEN/sizeof(efi_char16_t)];
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efi_guid_t VendorGuid;
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__u32 DataSize;
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__u8 Data[1024];
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__u32 Status;
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__u32 Attributes;
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} __packed;
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2013-02-08 16:37:06 +01:00
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struct efivar_attribute {
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struct attribute attr;
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ssize_t (*show) (struct efivar_entry *entry, char *buf);
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ssize_t (*store)(struct efivar_entry *entry, const char *buf, size_t count);
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};
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#define EFIVAR_ATTR(_name, _mode, _show, _store) \
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struct efivar_attribute efivar_attr_##_name = { \
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.attr = {.name = __stringify(_name), .mode = _mode}, \
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.show = _show, \
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.store = _store, \
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};
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#define to_efivar_attr(_attr) container_of(_attr, struct efivar_attribute, attr)
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#define to_efivar_entry(obj) container_of(obj, struct efivar_entry, kobj)
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/*
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* Prototype for sysfs creation function
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*/
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static int
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efivar_create_sysfs_entry(struct efivar_entry *new_var);
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static ssize_t
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efivar_guid_read(struct efivar_entry *entry, char *buf)
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{
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struct efi_variable *var = &entry->var;
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char *str = buf;
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if (!entry || !buf)
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return 0;
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2014-12-18 16:02:17 +01:00
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efi_guid_to_str(&var->VendorGuid, str);
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2013-02-08 16:37:06 +01:00
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str += strlen(str);
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str += sprintf(str, "\n");
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return str - buf;
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}
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static ssize_t
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efivar_attr_read(struct efivar_entry *entry, char *buf)
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{
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struct efi_variable *var = &entry->var;
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char *str = buf;
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if (!entry || !buf)
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return -EINVAL;
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var->DataSize = 1024;
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if (efivar_entry_get(entry, &var->Attributes, &var->DataSize, var->Data))
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return -EIO;
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if (var->Attributes & EFI_VARIABLE_NON_VOLATILE)
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str += sprintf(str, "EFI_VARIABLE_NON_VOLATILE\n");
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if (var->Attributes & EFI_VARIABLE_BOOTSERVICE_ACCESS)
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str += sprintf(str, "EFI_VARIABLE_BOOTSERVICE_ACCESS\n");
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if (var->Attributes & EFI_VARIABLE_RUNTIME_ACCESS)
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str += sprintf(str, "EFI_VARIABLE_RUNTIME_ACCESS\n");
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if (var->Attributes & EFI_VARIABLE_HARDWARE_ERROR_RECORD)
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str += sprintf(str, "EFI_VARIABLE_HARDWARE_ERROR_RECORD\n");
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if (var->Attributes & EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS)
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str += sprintf(str,
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"EFI_VARIABLE_AUTHENTICATED_WRITE_ACCESS\n");
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if (var->Attributes &
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EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS)
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str += sprintf(str,
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"EFI_VARIABLE_TIME_BASED_AUTHENTICATED_WRITE_ACCESS\n");
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if (var->Attributes & EFI_VARIABLE_APPEND_WRITE)
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str += sprintf(str, "EFI_VARIABLE_APPEND_WRITE\n");
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return str - buf;
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}
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static ssize_t
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efivar_size_read(struct efivar_entry *entry, char *buf)
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{
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struct efi_variable *var = &entry->var;
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char *str = buf;
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if (!entry || !buf)
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return -EINVAL;
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var->DataSize = 1024;
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if (efivar_entry_get(entry, &var->Attributes, &var->DataSize, var->Data))
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return -EIO;
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str += sprintf(str, "0x%lx\n", var->DataSize);
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return str - buf;
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}
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static ssize_t
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efivar_data_read(struct efivar_entry *entry, char *buf)
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{
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struct efi_variable *var = &entry->var;
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if (!entry || !buf)
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return -EINVAL;
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var->DataSize = 1024;
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if (efivar_entry_get(entry, &var->Attributes, &var->DataSize, var->Data))
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return -EIO;
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memcpy(buf, var->Data, var->DataSize);
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return var->DataSize;
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}
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2014-03-17 16:08:34 +01:00
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static inline int
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sanity_check(struct efi_variable *var, efi_char16_t *name, efi_guid_t vendor,
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unsigned long size, u32 attributes, u8 *data)
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{
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/*
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* If only updating the variable data, then the name
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* and guid should remain the same
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*/
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if (memcmp(name, var->VariableName, sizeof(var->VariableName)) ||
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efi_guidcmp(vendor, var->VendorGuid)) {
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printk(KERN_ERR "efivars: Cannot edit the wrong variable!\n");
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return -EINVAL;
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}
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if ((size <= 0) || (attributes == 0)){
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printk(KERN_ERR "efivars: DataSize & Attributes must be valid!\n");
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return -EINVAL;
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}
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if ((attributes & ~EFI_VARIABLE_MASK) != 0 ||
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2016-02-08 20:48:14 +01:00
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efivar_validate(vendor, name, data, size) == false) {
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2014-03-17 16:08:34 +01:00
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printk(KERN_ERR "efivars: Malformed variable content\n");
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return -EINVAL;
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}
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return 0;
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}
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2014-03-17 16:36:37 +01:00
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static inline bool is_compat(void)
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{
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2016-03-22 22:25:16 +01:00
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if (IS_ENABLED(CONFIG_COMPAT) && in_compat_syscall())
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2014-03-17 16:36:37 +01:00
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return true;
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return false;
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}
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static void
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copy_out_compat(struct efi_variable *dst, struct compat_efi_variable *src)
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{
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memcpy(dst->VariableName, src->VariableName, EFI_VAR_NAME_LEN);
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memcpy(dst->Data, src->Data, sizeof(src->Data));
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dst->VendorGuid = src->VendorGuid;
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dst->DataSize = src->DataSize;
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dst->Attributes = src->Attributes;
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}
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2013-02-08 16:37:06 +01:00
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/*
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* We allow each variable to be edited via rewriting the
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* entire efi variable structure.
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*/
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static ssize_t
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efivar_store_raw(struct efivar_entry *entry, const char *buf, size_t count)
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{
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struct efi_variable *new_var, *var = &entry->var;
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2014-03-16 13:14:49 +01:00
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efi_char16_t *name;
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unsigned long size;
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efi_guid_t vendor;
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u32 attributes;
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u8 *data;
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2013-02-08 16:37:06 +01:00
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int err;
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2014-03-17 16:36:37 +01:00
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if (is_compat()) {
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struct compat_efi_variable *compat;
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2013-02-08 16:37:06 +01:00
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2014-03-17 16:36:37 +01:00
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if (count != sizeof(*compat))
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return -EINVAL;
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2014-03-16 13:14:49 +01:00
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2014-03-17 16:36:37 +01:00
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compat = (struct compat_efi_variable *)buf;
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attributes = compat->Attributes;
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vendor = compat->VendorGuid;
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name = compat->VariableName;
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size = compat->DataSize;
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data = compat->Data;
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2014-03-16 13:14:49 +01:00
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2014-03-17 16:36:37 +01:00
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err = sanity_check(var, name, vendor, size, attributes, data);
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if (err)
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return err;
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copy_out_compat(&entry->var, compat);
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} else {
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if (count != sizeof(struct efi_variable))
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return -EINVAL;
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new_var = (struct efi_variable *)buf;
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2013-02-08 16:37:06 +01:00
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2014-03-17 16:36:37 +01:00
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attributes = new_var->Attributes;
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vendor = new_var->VendorGuid;
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name = new_var->VariableName;
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size = new_var->DataSize;
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data = new_var->Data;
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err = sanity_check(var, name, vendor, size, attributes, data);
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if (err)
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return err;
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memcpy(&entry->var, new_var, count);
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}
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2013-02-08 16:37:06 +01:00
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2014-03-16 13:14:49 +01:00
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err = efivar_entry_set(entry, attributes, size, data, NULL);
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2013-02-08 16:37:06 +01:00
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if (err) {
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printk(KERN_WARNING "efivars: set_variable() failed: status=%d\n", err);
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return -EIO;
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}
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return count;
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}
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static ssize_t
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efivar_show_raw(struct efivar_entry *entry, char *buf)
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{
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struct efi_variable *var = &entry->var;
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2014-03-17 16:36:37 +01:00
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struct compat_efi_variable *compat;
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size_t size;
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2013-02-08 16:37:06 +01:00
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if (!entry || !buf)
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return 0;
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var->DataSize = 1024;
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if (efivar_entry_get(entry, &entry->var.Attributes,
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&entry->var.DataSize, entry->var.Data))
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return -EIO;
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2014-03-17 16:36:37 +01:00
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if (is_compat()) {
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compat = (struct compat_efi_variable *)buf;
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size = sizeof(*compat);
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memcpy(compat->VariableName, var->VariableName,
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EFI_VAR_NAME_LEN);
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memcpy(compat->Data, var->Data, sizeof(compat->Data));
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compat->VendorGuid = var->VendorGuid;
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compat->DataSize = var->DataSize;
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compat->Attributes = var->Attributes;
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|
} else {
|
|
|
|
size = sizeof(*var);
|
|
|
|
memcpy(buf, var, size);
|
|
|
|
}
|
2013-02-08 16:37:06 +01:00
|
|
|
|
2014-03-17 16:36:37 +01:00
|
|
|
return size;
|
2013-02-08 16:37:06 +01:00
|
|
|
}
|
|
|
|
|
|
|
|
/*
|
|
|
|
* Generic read/write functions that call the specific functions of
|
|
|
|
* the attributes...
|
|
|
|
*/
|
|
|
|
static ssize_t efivar_attr_show(struct kobject *kobj, struct attribute *attr,
|
|
|
|
char *buf)
|
|
|
|
{
|
|
|
|
struct efivar_entry *var = to_efivar_entry(kobj);
|
|
|
|
struct efivar_attribute *efivar_attr = to_efivar_attr(attr);
|
|
|
|
ssize_t ret = -EIO;
|
|
|
|
|
|
|
|
if (!capable(CAP_SYS_ADMIN))
|
|
|
|
return -EACCES;
|
|
|
|
|
|
|
|
if (efivar_attr->show) {
|
|
|
|
ret = efivar_attr->show(var, buf);
|
|
|
|
}
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
|
|
|
|
static ssize_t efivar_attr_store(struct kobject *kobj, struct attribute *attr,
|
|
|
|
const char *buf, size_t count)
|
|
|
|
{
|
|
|
|
struct efivar_entry *var = to_efivar_entry(kobj);
|
|
|
|
struct efivar_attribute *efivar_attr = to_efivar_attr(attr);
|
|
|
|
ssize_t ret = -EIO;
|
|
|
|
|
|
|
|
if (!capable(CAP_SYS_ADMIN))
|
|
|
|
return -EACCES;
|
|
|
|
|
|
|
|
if (efivar_attr->store)
|
|
|
|
ret = efivar_attr->store(var, buf, count);
|
|
|
|
|
|
|
|
return ret;
|
|
|
|
}
|
|
|
|
|
|
|
|
static const struct sysfs_ops efivar_attr_ops = {
|
|
|
|
.show = efivar_attr_show,
|
|
|
|
.store = efivar_attr_store,
|
|
|
|
};
|
|
|
|
|
|
|
|
static void efivar_release(struct kobject *kobj)
|
|
|
|
{
|
2016-02-01 23:07:02 +01:00
|
|
|
struct efivar_entry *var = to_efivar_entry(kobj);
|
2013-02-08 16:37:06 +01:00
|
|
|
kfree(var);
|
|
|
|
}
|
|
|
|
|
|
|
|
static EFIVAR_ATTR(guid, 0400, efivar_guid_read, NULL);
|
|
|
|
static EFIVAR_ATTR(attributes, 0400, efivar_attr_read, NULL);
|
|
|
|
static EFIVAR_ATTR(size, 0400, efivar_size_read, NULL);
|
|
|
|
static EFIVAR_ATTR(data, 0400, efivar_data_read, NULL);
|
|
|
|
static EFIVAR_ATTR(raw_var, 0600, efivar_show_raw, efivar_store_raw);
|
|
|
|
|
|
|
|
static struct attribute *def_attrs[] = {
|
|
|
|
&efivar_attr_guid.attr,
|
|
|
|
&efivar_attr_size.attr,
|
|
|
|
&efivar_attr_attributes.attr,
|
|
|
|
&efivar_attr_data.attr,
|
|
|
|
&efivar_attr_raw_var.attr,
|
|
|
|
NULL,
|
|
|
|
};
|
|
|
|
|
|
|
|
static struct kobj_type efivar_ktype = {
|
|
|
|
.release = efivar_release,
|
|
|
|
.sysfs_ops = &efivar_attr_ops,
|
|
|
|
.default_attrs = def_attrs,
|
|
|
|
};
|
|
|
|
|
|
|
|
static ssize_t efivar_create(struct file *filp, struct kobject *kobj,
|
|
|
|
struct bin_attribute *bin_attr,
|
|
|
|
char *buf, loff_t pos, size_t count)
|
|
|
|
{
|
2014-03-17 16:36:37 +01:00
|
|
|
struct compat_efi_variable *compat = (struct compat_efi_variable *)buf;
|
2013-02-08 16:37:06 +01:00
|
|
|
struct efi_variable *new_var = (struct efi_variable *)buf;
|
|
|
|
struct efivar_entry *new_entry;
|
2014-03-17 16:36:37 +01:00
|
|
|
bool need_compat = is_compat();
|
2014-03-17 11:57:00 +01:00
|
|
|
efi_char16_t *name;
|
2014-03-16 13:14:49 +01:00
|
|
|
unsigned long size;
|
|
|
|
u32 attributes;
|
|
|
|
u8 *data;
|
2013-02-08 16:37:06 +01:00
|
|
|
int err;
|
|
|
|
|
|
|
|
if (!capable(CAP_SYS_ADMIN))
|
|
|
|
return -EACCES;
|
|
|
|
|
2014-03-17 16:36:37 +01:00
|
|
|
if (need_compat) {
|
|
|
|
if (count != sizeof(*compat))
|
|
|
|
return -EINVAL;
|
|
|
|
|
|
|
|
attributes = compat->Attributes;
|
|
|
|
name = compat->VariableName;
|
|
|
|
size = compat->DataSize;
|
|
|
|
data = compat->Data;
|
|
|
|
} else {
|
|
|
|
if (count != sizeof(*new_var))
|
|
|
|
return -EINVAL;
|
|
|
|
|
|
|
|
attributes = new_var->Attributes;
|
|
|
|
name = new_var->VariableName;
|
|
|
|
size = new_var->DataSize;
|
|
|
|
data = new_var->Data;
|
|
|
|
}
|
2014-03-16 13:14:49 +01:00
|
|
|
|
|
|
|
if ((attributes & ~EFI_VARIABLE_MASK) != 0 ||
|
2016-02-08 20:48:14 +01:00
|
|
|
efivar_validate(new_var->VendorGuid, name, data,
|
|
|
|
size) == false) {
|
2013-02-08 16:37:06 +01:00
|
|
|
printk(KERN_ERR "efivars: Malformed variable content\n");
|
|
|
|
return -EINVAL;
|
|
|
|
}
|
|
|
|
|
|
|
|
new_entry = kzalloc(sizeof(*new_entry), GFP_KERNEL);
|
|
|
|
if (!new_entry)
|
|
|
|
return -ENOMEM;
|
|
|
|
|
2014-03-17 16:36:37 +01:00
|
|
|
if (need_compat)
|
|
|
|
copy_out_compat(&new_entry->var, compat);
|
|
|
|
else
|
|
|
|
memcpy(&new_entry->var, new_var, sizeof(*new_var));
|
2013-02-08 16:37:06 +01:00
|
|
|
|
2014-03-16 13:14:49 +01:00
|
|
|
err = efivar_entry_set(new_entry, attributes, size,
|
|
|
|
data, &efivar_sysfs_list);
|
2013-02-08 16:37:06 +01:00
|
|
|
if (err) {
|
|
|
|
if (err == -EEXIST)
|
|
|
|
err = -EINVAL;
|
|
|
|
goto out;
|
|
|
|
}
|
|
|
|
|
|
|
|
if (efivar_create_sysfs_entry(new_entry)) {
|
|
|
|
printk(KERN_WARNING "efivars: failed to create sysfs entry.\n");
|
|
|
|
kfree(new_entry);
|
|
|
|
}
|
|
|
|
return count;
|
|
|
|
|
|
|
|
out:
|
|
|
|
kfree(new_entry);
|
|
|
|
return err;
|
|
|
|
}
|
|
|
|
|
|
|
|
static ssize_t efivar_delete(struct file *filp, struct kobject *kobj,
|
|
|
|
struct bin_attribute *bin_attr,
|
|
|
|
char *buf, loff_t pos, size_t count)
|
|
|
|
{
|
|
|
|
struct efi_variable *del_var = (struct efi_variable *)buf;
|
2014-03-17 16:36:37 +01:00
|
|
|
struct compat_efi_variable *compat;
|
2013-02-08 16:37:06 +01:00
|
|
|
struct efivar_entry *entry;
|
2014-03-16 13:14:49 +01:00
|
|
|
efi_char16_t *name;
|
|
|
|
efi_guid_t vendor;
|
2013-02-08 16:37:06 +01:00
|
|
|
int err = 0;
|
|
|
|
|
|
|
|
if (!capable(CAP_SYS_ADMIN))
|
|
|
|
return -EACCES;
|
|
|
|
|
2014-03-17 16:36:37 +01:00
|
|
|
if (is_compat()) {
|
|
|
|
if (count != sizeof(*compat))
|
|
|
|
return -EINVAL;
|
|
|
|
|
|
|
|
compat = (struct compat_efi_variable *)buf;
|
|
|
|
name = compat->VariableName;
|
|
|
|
vendor = compat->VendorGuid;
|
|
|
|
} else {
|
|
|
|
if (count != sizeof(*del_var))
|
|
|
|
return -EINVAL;
|
2014-03-17 10:17:28 +01:00
|
|
|
|
2014-03-17 16:36:37 +01:00
|
|
|
name = del_var->VariableName;
|
|
|
|
vendor = del_var->VendorGuid;
|
|
|
|
}
|
2014-03-16 13:14:49 +01:00
|
|
|
|
2013-02-08 16:37:06 +01:00
|
|
|
efivar_entry_iter_begin();
|
2014-03-16 13:14:49 +01:00
|
|
|
entry = efivar_entry_find(name, vendor, &efivar_sysfs_list, true);
|
2013-02-08 16:37:06 +01:00
|
|
|
if (!entry)
|
|
|
|
err = -EINVAL;
|
|
|
|
else if (__efivar_entry_delete(entry))
|
|
|
|
err = -EIO;
|
|
|
|
|
efivars, efi-pstore: Hold off deletion of sysfs entry until the scan is completed
Currently, when mounting pstore file system, a read callback of
efi_pstore driver runs mutiple times as below.
- In the first read callback, scan efivar_sysfs_list from head and pass
a kmsg buffer of a entry to an upper pstore layer.
- In the second read callback, rescan efivar_sysfs_list from the entry
and pass another kmsg buffer to it.
- Repeat the scan and pass until the end of efivar_sysfs_list.
In this process, an entry is read across the multiple read function
calls. To avoid race between the read and erasion, the whole process
above is protected by a spinlock, holding in open() and releasing in
close().
At the same time, kmemdup() is called to pass the buffer to pstore
filesystem during it. And then, it causes a following lockdep warning.
To make the dynamic memory allocation runnable without taking spinlock,
holding off a deletion of sysfs entry if it happens while scanning it
via efi_pstore, and deleting it after the scan is completed.
To implement it, this patch introduces two flags, scanning and deleting,
to efivar_entry.
On the code basis, it seems that all the scanning and deleting logic is
not needed because __efivars->lock are not dropped when reading from the
EFI variable store.
But, the scanning and deleting logic is still needed because an
efi-pstore and a pstore filesystem works as follows.
In case an entry(A) is found, the pointer is saved to psi->data. And
efi_pstore_read() passes the entry(A) to a pstore filesystem by
releasing __efivars->lock.
And then, the pstore filesystem calls efi_pstore_read() again and the
same entry(A), which is saved to psi->data, is used for resuming to scan
a sysfs-list.
So, to protect the entry(A), the logic is needed.
[ 1.143710] ------------[ cut here ]------------
[ 1.144058] WARNING: CPU: 1 PID: 1 at kernel/lockdep.c:2740 lockdep_trace_alloc+0x104/0x110()
[ 1.144058] DEBUG_LOCKS_WARN_ON(irqs_disabled_flags(flags))
[ 1.144058] Modules linked in:
[ 1.144058] CPU: 1 PID: 1 Comm: systemd Not tainted 3.11.0-rc5 #2
[ 1.144058] 0000000000000009 ffff8800797e9ae0 ffffffff816614a5 ffff8800797e9b28
[ 1.144058] ffff8800797e9b18 ffffffff8105510d 0000000000000080 0000000000000046
[ 1.144058] 00000000000000d0 00000000000003af ffffffff81ccd0c0 ffff8800797e9b78
[ 1.144058] Call Trace:
[ 1.144058] [<ffffffff816614a5>] dump_stack+0x54/0x74
[ 1.144058] [<ffffffff8105510d>] warn_slowpath_common+0x7d/0xa0
[ 1.144058] [<ffffffff8105517c>] warn_slowpath_fmt+0x4c/0x50
[ 1.144058] [<ffffffff8131290f>] ? vsscanf+0x57f/0x7b0
[ 1.144058] [<ffffffff810bbd74>] lockdep_trace_alloc+0x104/0x110
[ 1.144058] [<ffffffff81192da0>] __kmalloc_track_caller+0x50/0x280
[ 1.144058] [<ffffffff815147bb>] ? efi_pstore_read_func.part.1+0x12b/0x170
[ 1.144058] [<ffffffff8115b260>] kmemdup+0x20/0x50
[ 1.144058] [<ffffffff815147bb>] efi_pstore_read_func.part.1+0x12b/0x170
[ 1.144058] [<ffffffff81514800>] ? efi_pstore_read_func.part.1+0x170/0x170
[ 1.144058] [<ffffffff815148b4>] efi_pstore_read_func+0xb4/0xe0
[ 1.144058] [<ffffffff81512b7b>] __efivar_entry_iter+0xfb/0x120
[ 1.144058] [<ffffffff8151428f>] efi_pstore_read+0x3f/0x50
[ 1.144058] [<ffffffff8128d7ba>] pstore_get_records+0x9a/0x150
[ 1.158207] [<ffffffff812af25c>] ? selinux_d_instantiate+0x1c/0x20
[ 1.158207] [<ffffffff8128ce30>] ? parse_options+0x80/0x80
[ 1.158207] [<ffffffff8128ced5>] pstore_fill_super+0xa5/0xc0
[ 1.158207] [<ffffffff811ae7d2>] mount_single+0xa2/0xd0
[ 1.158207] [<ffffffff8128ccf8>] pstore_mount+0x18/0x20
[ 1.158207] [<ffffffff811ae8b9>] mount_fs+0x39/0x1b0
[ 1.158207] [<ffffffff81160550>] ? __alloc_percpu+0x10/0x20
[ 1.158207] [<ffffffff811c9493>] vfs_kern_mount+0x63/0xf0
[ 1.158207] [<ffffffff811cbb0e>] do_mount+0x23e/0xa20
[ 1.158207] [<ffffffff8115b51b>] ? strndup_user+0x4b/0xf0
[ 1.158207] [<ffffffff811cc373>] SyS_mount+0x83/0xc0
[ 1.158207] [<ffffffff81673cc2>] system_call_fastpath+0x16/0x1b
[ 1.158207] ---[ end trace 61981bc62de9f6f4 ]---
Signed-off-by: Seiji Aguchi <seiji.aguchi@hds.com>
Tested-by: Madper Xie <cxie@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2013-10-30 20:27:26 +01:00
|
|
|
if (err) {
|
|
|
|
efivar_entry_iter_end();
|
2013-02-08 16:37:06 +01:00
|
|
|
return err;
|
efivars, efi-pstore: Hold off deletion of sysfs entry until the scan is completed
Currently, when mounting pstore file system, a read callback of
efi_pstore driver runs mutiple times as below.
- In the first read callback, scan efivar_sysfs_list from head and pass
a kmsg buffer of a entry to an upper pstore layer.
- In the second read callback, rescan efivar_sysfs_list from the entry
and pass another kmsg buffer to it.
- Repeat the scan and pass until the end of efivar_sysfs_list.
In this process, an entry is read across the multiple read function
calls. To avoid race between the read and erasion, the whole process
above is protected by a spinlock, holding in open() and releasing in
close().
At the same time, kmemdup() is called to pass the buffer to pstore
filesystem during it. And then, it causes a following lockdep warning.
To make the dynamic memory allocation runnable without taking spinlock,
holding off a deletion of sysfs entry if it happens while scanning it
via efi_pstore, and deleting it after the scan is completed.
To implement it, this patch introduces two flags, scanning and deleting,
to efivar_entry.
On the code basis, it seems that all the scanning and deleting logic is
not needed because __efivars->lock are not dropped when reading from the
EFI variable store.
But, the scanning and deleting logic is still needed because an
efi-pstore and a pstore filesystem works as follows.
In case an entry(A) is found, the pointer is saved to psi->data. And
efi_pstore_read() passes the entry(A) to a pstore filesystem by
releasing __efivars->lock.
And then, the pstore filesystem calls efi_pstore_read() again and the
same entry(A), which is saved to psi->data, is used for resuming to scan
a sysfs-list.
So, to protect the entry(A), the logic is needed.
[ 1.143710] ------------[ cut here ]------------
[ 1.144058] WARNING: CPU: 1 PID: 1 at kernel/lockdep.c:2740 lockdep_trace_alloc+0x104/0x110()
[ 1.144058] DEBUG_LOCKS_WARN_ON(irqs_disabled_flags(flags))
[ 1.144058] Modules linked in:
[ 1.144058] CPU: 1 PID: 1 Comm: systemd Not tainted 3.11.0-rc5 #2
[ 1.144058] 0000000000000009 ffff8800797e9ae0 ffffffff816614a5 ffff8800797e9b28
[ 1.144058] ffff8800797e9b18 ffffffff8105510d 0000000000000080 0000000000000046
[ 1.144058] 00000000000000d0 00000000000003af ffffffff81ccd0c0 ffff8800797e9b78
[ 1.144058] Call Trace:
[ 1.144058] [<ffffffff816614a5>] dump_stack+0x54/0x74
[ 1.144058] [<ffffffff8105510d>] warn_slowpath_common+0x7d/0xa0
[ 1.144058] [<ffffffff8105517c>] warn_slowpath_fmt+0x4c/0x50
[ 1.144058] [<ffffffff8131290f>] ? vsscanf+0x57f/0x7b0
[ 1.144058] [<ffffffff810bbd74>] lockdep_trace_alloc+0x104/0x110
[ 1.144058] [<ffffffff81192da0>] __kmalloc_track_caller+0x50/0x280
[ 1.144058] [<ffffffff815147bb>] ? efi_pstore_read_func.part.1+0x12b/0x170
[ 1.144058] [<ffffffff8115b260>] kmemdup+0x20/0x50
[ 1.144058] [<ffffffff815147bb>] efi_pstore_read_func.part.1+0x12b/0x170
[ 1.144058] [<ffffffff81514800>] ? efi_pstore_read_func.part.1+0x170/0x170
[ 1.144058] [<ffffffff815148b4>] efi_pstore_read_func+0xb4/0xe0
[ 1.144058] [<ffffffff81512b7b>] __efivar_entry_iter+0xfb/0x120
[ 1.144058] [<ffffffff8151428f>] efi_pstore_read+0x3f/0x50
[ 1.144058] [<ffffffff8128d7ba>] pstore_get_records+0x9a/0x150
[ 1.158207] [<ffffffff812af25c>] ? selinux_d_instantiate+0x1c/0x20
[ 1.158207] [<ffffffff8128ce30>] ? parse_options+0x80/0x80
[ 1.158207] [<ffffffff8128ced5>] pstore_fill_super+0xa5/0xc0
[ 1.158207] [<ffffffff811ae7d2>] mount_single+0xa2/0xd0
[ 1.158207] [<ffffffff8128ccf8>] pstore_mount+0x18/0x20
[ 1.158207] [<ffffffff811ae8b9>] mount_fs+0x39/0x1b0
[ 1.158207] [<ffffffff81160550>] ? __alloc_percpu+0x10/0x20
[ 1.158207] [<ffffffff811c9493>] vfs_kern_mount+0x63/0xf0
[ 1.158207] [<ffffffff811cbb0e>] do_mount+0x23e/0xa20
[ 1.158207] [<ffffffff8115b51b>] ? strndup_user+0x4b/0xf0
[ 1.158207] [<ffffffff811cc373>] SyS_mount+0x83/0xc0
[ 1.158207] [<ffffffff81673cc2>] system_call_fastpath+0x16/0x1b
[ 1.158207] ---[ end trace 61981bc62de9f6f4 ]---
Signed-off-by: Seiji Aguchi <seiji.aguchi@hds.com>
Tested-by: Madper Xie <cxie@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2013-10-30 20:27:26 +01:00
|
|
|
}
|
2013-02-08 16:37:06 +01:00
|
|
|
|
efivars, efi-pstore: Hold off deletion of sysfs entry until the scan is completed
Currently, when mounting pstore file system, a read callback of
efi_pstore driver runs mutiple times as below.
- In the first read callback, scan efivar_sysfs_list from head and pass
a kmsg buffer of a entry to an upper pstore layer.
- In the second read callback, rescan efivar_sysfs_list from the entry
and pass another kmsg buffer to it.
- Repeat the scan and pass until the end of efivar_sysfs_list.
In this process, an entry is read across the multiple read function
calls. To avoid race between the read and erasion, the whole process
above is protected by a spinlock, holding in open() and releasing in
close().
At the same time, kmemdup() is called to pass the buffer to pstore
filesystem during it. And then, it causes a following lockdep warning.
To make the dynamic memory allocation runnable without taking spinlock,
holding off a deletion of sysfs entry if it happens while scanning it
via efi_pstore, and deleting it after the scan is completed.
To implement it, this patch introduces two flags, scanning and deleting,
to efivar_entry.
On the code basis, it seems that all the scanning and deleting logic is
not needed because __efivars->lock are not dropped when reading from the
EFI variable store.
But, the scanning and deleting logic is still needed because an
efi-pstore and a pstore filesystem works as follows.
In case an entry(A) is found, the pointer is saved to psi->data. And
efi_pstore_read() passes the entry(A) to a pstore filesystem by
releasing __efivars->lock.
And then, the pstore filesystem calls efi_pstore_read() again and the
same entry(A), which is saved to psi->data, is used for resuming to scan
a sysfs-list.
So, to protect the entry(A), the logic is needed.
[ 1.143710] ------------[ cut here ]------------
[ 1.144058] WARNING: CPU: 1 PID: 1 at kernel/lockdep.c:2740 lockdep_trace_alloc+0x104/0x110()
[ 1.144058] DEBUG_LOCKS_WARN_ON(irqs_disabled_flags(flags))
[ 1.144058] Modules linked in:
[ 1.144058] CPU: 1 PID: 1 Comm: systemd Not tainted 3.11.0-rc5 #2
[ 1.144058] 0000000000000009 ffff8800797e9ae0 ffffffff816614a5 ffff8800797e9b28
[ 1.144058] ffff8800797e9b18 ffffffff8105510d 0000000000000080 0000000000000046
[ 1.144058] 00000000000000d0 00000000000003af ffffffff81ccd0c0 ffff8800797e9b78
[ 1.144058] Call Trace:
[ 1.144058] [<ffffffff816614a5>] dump_stack+0x54/0x74
[ 1.144058] [<ffffffff8105510d>] warn_slowpath_common+0x7d/0xa0
[ 1.144058] [<ffffffff8105517c>] warn_slowpath_fmt+0x4c/0x50
[ 1.144058] [<ffffffff8131290f>] ? vsscanf+0x57f/0x7b0
[ 1.144058] [<ffffffff810bbd74>] lockdep_trace_alloc+0x104/0x110
[ 1.144058] [<ffffffff81192da0>] __kmalloc_track_caller+0x50/0x280
[ 1.144058] [<ffffffff815147bb>] ? efi_pstore_read_func.part.1+0x12b/0x170
[ 1.144058] [<ffffffff8115b260>] kmemdup+0x20/0x50
[ 1.144058] [<ffffffff815147bb>] efi_pstore_read_func.part.1+0x12b/0x170
[ 1.144058] [<ffffffff81514800>] ? efi_pstore_read_func.part.1+0x170/0x170
[ 1.144058] [<ffffffff815148b4>] efi_pstore_read_func+0xb4/0xe0
[ 1.144058] [<ffffffff81512b7b>] __efivar_entry_iter+0xfb/0x120
[ 1.144058] [<ffffffff8151428f>] efi_pstore_read+0x3f/0x50
[ 1.144058] [<ffffffff8128d7ba>] pstore_get_records+0x9a/0x150
[ 1.158207] [<ffffffff812af25c>] ? selinux_d_instantiate+0x1c/0x20
[ 1.158207] [<ffffffff8128ce30>] ? parse_options+0x80/0x80
[ 1.158207] [<ffffffff8128ced5>] pstore_fill_super+0xa5/0xc0
[ 1.158207] [<ffffffff811ae7d2>] mount_single+0xa2/0xd0
[ 1.158207] [<ffffffff8128ccf8>] pstore_mount+0x18/0x20
[ 1.158207] [<ffffffff811ae8b9>] mount_fs+0x39/0x1b0
[ 1.158207] [<ffffffff81160550>] ? __alloc_percpu+0x10/0x20
[ 1.158207] [<ffffffff811c9493>] vfs_kern_mount+0x63/0xf0
[ 1.158207] [<ffffffff811cbb0e>] do_mount+0x23e/0xa20
[ 1.158207] [<ffffffff8115b51b>] ? strndup_user+0x4b/0xf0
[ 1.158207] [<ffffffff811cc373>] SyS_mount+0x83/0xc0
[ 1.158207] [<ffffffff81673cc2>] system_call_fastpath+0x16/0x1b
[ 1.158207] ---[ end trace 61981bc62de9f6f4 ]---
Signed-off-by: Seiji Aguchi <seiji.aguchi@hds.com>
Tested-by: Madper Xie <cxie@redhat.com>
Cc: stable@kernel.org
Signed-off-by: Matt Fleming <matt.fleming@intel.com>
2013-10-30 20:27:26 +01:00
|
|
|
if (!entry->scanning) {
|
|
|
|
efivar_entry_iter_end();
|
|
|
|
efivar_unregister(entry);
|
|
|
|
} else
|
|
|
|
efivar_entry_iter_end();
|
2013-02-08 16:37:06 +01:00
|
|
|
|
|
|
|
/* It's dead Jim.... */
|
|
|
|
return count;
|
|
|
|
}
|
|
|
|
|
|
|
|
/**
|
|
|
|
* efivar_create_sysfs_entry - create a new entry in sysfs
|
|
|
|
* @new_var: efivar entry to create
|
|
|
|
*
|
2015-04-21 11:21:53 +02:00
|
|
|
* Returns 0 on success, negative error code on failure
|
2013-02-08 16:37:06 +01:00
|
|
|
*/
|
|
|
|
static int
|
|
|
|
efivar_create_sysfs_entry(struct efivar_entry *new_var)
|
|
|
|
{
|
2016-02-08 20:48:12 +01:00
|
|
|
int short_name_size;
|
2013-02-08 16:37:06 +01:00
|
|
|
char *short_name;
|
2016-02-08 20:48:12 +01:00
|
|
|
unsigned long utf8_name_size;
|
|
|
|
efi_char16_t *variable_name = new_var->var.VariableName;
|
2015-04-21 11:21:53 +02:00
|
|
|
int ret;
|
2013-02-08 16:37:06 +01:00
|
|
|
|
|
|
|
/*
|
2016-02-08 20:48:12 +01:00
|
|
|
* Length of the variable bytes in UTF8, plus the '-' separator,
|
2013-02-08 16:37:06 +01:00
|
|
|
* plus the GUID, plus trailing NUL
|
|
|
|
*/
|
2016-02-08 20:48:12 +01:00
|
|
|
utf8_name_size = ucs2_utf8size(variable_name);
|
|
|
|
short_name_size = utf8_name_size + 1 + EFI_VARIABLE_GUID_LEN + 1;
|
2013-02-08 16:37:06 +01:00
|
|
|
|
2016-02-08 20:48:12 +01:00
|
|
|
short_name = kmalloc(short_name_size, GFP_KERNEL);
|
2013-04-30 09:43:44 +02:00
|
|
|
if (!short_name)
|
2015-04-21 11:21:53 +02:00
|
|
|
return -ENOMEM;
|
2013-02-08 16:37:06 +01:00
|
|
|
|
2016-02-08 20:48:12 +01:00
|
|
|
ucs2_as_utf8(short_name, variable_name, short_name_size);
|
|
|
|
|
2013-02-08 16:37:06 +01:00
|
|
|
/* This is ugly, but necessary to separate one vendor's
|
|
|
|
private variables from another's. */
|
2016-02-08 20:48:12 +01:00
|
|
|
short_name[utf8_name_size] = '-';
|
2014-12-18 16:02:17 +01:00
|
|
|
efi_guid_to_str(&new_var->var.VendorGuid,
|
2016-02-08 20:48:12 +01:00
|
|
|
short_name + utf8_name_size + 1);
|
2013-02-08 16:37:06 +01:00
|
|
|
|
|
|
|
new_var->kobj.kset = efivars_kset;
|
|
|
|
|
2015-04-21 11:21:53 +02:00
|
|
|
ret = kobject_init_and_add(&new_var->kobj, &efivar_ktype,
|
2013-02-08 16:37:06 +01:00
|
|
|
NULL, "%s", short_name);
|
|
|
|
kfree(short_name);
|
2015-04-21 11:21:53 +02:00
|
|
|
if (ret)
|
|
|
|
return ret;
|
2013-02-08 16:37:06 +01:00
|
|
|
|
|
|
|
kobject_uevent(&new_var->kobj, KOBJ_ADD);
|
|
|
|
efivar_entry_add(new_var, &efivar_sysfs_list);
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
static int
|
|
|
|
create_efivars_bin_attributes(void)
|
|
|
|
{
|
|
|
|
struct bin_attribute *attr;
|
|
|
|
int error;
|
|
|
|
|
|
|
|
/* new_var */
|
|
|
|
attr = kzalloc(sizeof(*attr), GFP_KERNEL);
|
|
|
|
if (!attr)
|
|
|
|
return -ENOMEM;
|
|
|
|
|
|
|
|
attr->attr.name = "new_var";
|
|
|
|
attr->attr.mode = 0200;
|
|
|
|
attr->write = efivar_create;
|
|
|
|
efivars_new_var = attr;
|
|
|
|
|
|
|
|
/* del_var */
|
|
|
|
attr = kzalloc(sizeof(*attr), GFP_KERNEL);
|
|
|
|
if (!attr) {
|
|
|
|
error = -ENOMEM;
|
|
|
|
goto out_free;
|
|
|
|
}
|
|
|
|
attr->attr.name = "del_var";
|
|
|
|
attr->attr.mode = 0200;
|
|
|
|
attr->write = efivar_delete;
|
|
|
|
efivars_del_var = attr;
|
|
|
|
|
|
|
|
sysfs_bin_attr_init(efivars_new_var);
|
|
|
|
sysfs_bin_attr_init(efivars_del_var);
|
|
|
|
|
|
|
|
/* Register */
|
|
|
|
error = sysfs_create_bin_file(&efivars_kset->kobj, efivars_new_var);
|
|
|
|
if (error) {
|
|
|
|
printk(KERN_ERR "efivars: unable to create new_var sysfs file"
|
|
|
|
" due to error %d\n", error);
|
|
|
|
goto out_free;
|
|
|
|
}
|
|
|
|
|
|
|
|
error = sysfs_create_bin_file(&efivars_kset->kobj, efivars_del_var);
|
|
|
|
if (error) {
|
|
|
|
printk(KERN_ERR "efivars: unable to create del_var sysfs file"
|
|
|
|
" due to error %d\n", error);
|
|
|
|
sysfs_remove_bin_file(&efivars_kset->kobj, efivars_new_var);
|
|
|
|
goto out_free;
|
|
|
|
}
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
out_free:
|
|
|
|
kfree(efivars_del_var);
|
|
|
|
efivars_del_var = NULL;
|
|
|
|
kfree(efivars_new_var);
|
|
|
|
efivars_new_var = NULL;
|
|
|
|
return error;
|
|
|
|
}
|
|
|
|
|
|
|
|
static int efivar_update_sysfs_entry(efi_char16_t *name, efi_guid_t vendor,
|
|
|
|
unsigned long name_size, void *data)
|
|
|
|
{
|
|
|
|
struct efivar_entry *entry = data;
|
|
|
|
|
|
|
|
if (efivar_entry_find(name, vendor, &efivar_sysfs_list, false))
|
|
|
|
return 0;
|
|
|
|
|
|
|
|
memcpy(entry->var.VariableName, name, name_size);
|
|
|
|
memcpy(&(entry->var.VendorGuid), &vendor, sizeof(efi_guid_t));
|
|
|
|
|
|
|
|
return 1;
|
|
|
|
}
|
|
|
|
|
|
|
|
static void efivar_update_sysfs_entries(struct work_struct *work)
|
|
|
|
{
|
|
|
|
struct efivar_entry *entry;
|
|
|
|
int err;
|
|
|
|
|
|
|
|
/* Add new sysfs entries */
|
|
|
|
while (1) {
|
2013-05-10 22:45:36 +02:00
|
|
|
entry = kzalloc(sizeof(*entry), GFP_KERNEL);
|
|
|
|
if (!entry)
|
|
|
|
return;
|
2013-02-08 16:37:06 +01:00
|
|
|
|
|
|
|
err = efivar_init(efivar_update_sysfs_entry, entry,
|
2016-05-06 23:39:30 +02:00
|
|
|
false, &efivar_sysfs_list);
|
2013-02-08 16:37:06 +01:00
|
|
|
if (!err)
|
|
|
|
break;
|
|
|
|
|
|
|
|
efivar_create_sysfs_entry(entry);
|
|
|
|
}
|
|
|
|
|
|
|
|
kfree(entry);
|
|
|
|
}
|
|
|
|
|
|
|
|
static int efivars_sysfs_callback(efi_char16_t *name, efi_guid_t vendor,
|
|
|
|
unsigned long name_size, void *data)
|
|
|
|
{
|
|
|
|
struct efivar_entry *entry;
|
|
|
|
|
|
|
|
entry = kzalloc(sizeof(*entry), GFP_KERNEL);
|
|
|
|
if (!entry)
|
|
|
|
return -ENOMEM;
|
|
|
|
|
|
|
|
memcpy(entry->var.VariableName, name, name_size);
|
|
|
|
memcpy(&(entry->var.VendorGuid), &vendor, sizeof(efi_guid_t));
|
|
|
|
|
|
|
|
efivar_create_sysfs_entry(entry);
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
|
|
|
static int efivar_sysfs_destroy(struct efivar_entry *entry, void *data)
|
|
|
|
{
|
|
|
|
efivar_entry_remove(entry);
|
|
|
|
efivar_unregister(entry);
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
|
2013-09-03 08:56:20 +02:00
|
|
|
static void efivars_sysfs_exit(void)
|
2013-02-08 16:37:06 +01:00
|
|
|
{
|
|
|
|
/* Remove all entries and destroy */
|
|
|
|
__efivar_entry_iter(efivar_sysfs_destroy, &efivar_sysfs_list, NULL, NULL);
|
|
|
|
|
|
|
|
if (efivars_new_var)
|
|
|
|
sysfs_remove_bin_file(&efivars_kset->kobj, efivars_new_var);
|
|
|
|
if (efivars_del_var)
|
|
|
|
sysfs_remove_bin_file(&efivars_kset->kobj, efivars_del_var);
|
|
|
|
kfree(efivars_new_var);
|
|
|
|
kfree(efivars_del_var);
|
|
|
|
kset_unregister(efivars_kset);
|
|
|
|
}
|
|
|
|
|
|
|
|
int efivars_sysfs_init(void)
|
|
|
|
{
|
|
|
|
struct kobject *parent_kobj = efivars_kobject();
|
|
|
|
int error = 0;
|
|
|
|
|
2013-07-11 08:30:33 +02:00
|
|
|
if (!efi_enabled(EFI_RUNTIME_SERVICES))
|
|
|
|
return -ENODEV;
|
|
|
|
|
2013-02-08 16:37:06 +01:00
|
|
|
/* No efivars has been registered yet */
|
|
|
|
if (!parent_kobj)
|
|
|
|
return 0;
|
|
|
|
|
|
|
|
printk(KERN_INFO "EFI Variables Facility v%s %s\n", EFIVARS_VERSION,
|
|
|
|
EFIVARS_DATE);
|
|
|
|
|
|
|
|
efivars_kset = kset_create_and_add("vars", NULL, parent_kobj);
|
|
|
|
if (!efivars_kset) {
|
|
|
|
printk(KERN_ERR "efivars: Subsystem registration failed.\n");
|
|
|
|
return -ENOMEM;
|
|
|
|
}
|
|
|
|
|
2016-05-06 23:39:30 +02:00
|
|
|
efivar_init(efivars_sysfs_callback, NULL, true, &efivar_sysfs_list);
|
2013-02-08 16:37:06 +01:00
|
|
|
|
|
|
|
error = create_efivars_bin_attributes();
|
|
|
|
if (error) {
|
|
|
|
efivars_sysfs_exit();
|
|
|
|
return error;
|
|
|
|
}
|
|
|
|
|
|
|
|
INIT_WORK(&efivar_work, efivar_update_sysfs_entries);
|
|
|
|
|
|
|
|
return 0;
|
|
|
|
}
|
|
|
|
EXPORT_SYMBOL_GPL(efivars_sysfs_init);
|
|
|
|
|
|
|
|
module_init(efivars_sysfs_init);
|
|
|
|
module_exit(efivars_sysfs_exit);
|