linux/security/tomoyo/gc.c

// SPDX-License-Identifier: GPL-2.0
/*
 * security/tomoyo/gc.c
 *
 * Copyright (C) 2005-2011  NTT DATA CORPORATION
 */

#include "common.h"
#include <linux/kthread.h>
#include <linux/slab.h>

/**
 * tomoyo_memory_free - Free memory for elements.
 *
 * @ptr:  Pointer to allocated memory.
 *
 * Returns nothing.
 *
 * Caller holds tomoyo_policy_lock mutex.
 */
static inline void tomoyo_memory_free(void *ptr)
{ … }

/* The list for "struct tomoyo_io_buffer". */
static LIST_HEAD(tomoyo_io_buffer_list);
/* Lock for protecting tomoyo_io_buffer_list. */
static DEFINE_SPINLOCK(tomoyo_io_buffer_list_lock);

/**
 * tomoyo_struct_used_by_io_buffer - Check whether the list element is used by /sys/kernel/security/tomoyo/ users or not.
 *
 * @element: Pointer to "struct list_head".
 *
 * Returns true if @element is used by /sys/kernel/security/tomoyo/ users,
 * false otherwise.
 */
static bool tomoyo_struct_used_by_io_buffer(const struct list_head *element)
{ … }

/**
 * tomoyo_name_used_by_io_buffer - Check whether the string is used by /sys/kernel/security/tomoyo/ users or not.
 *
 * @string: String to check.
 *
 * Returns true if @string is used by /sys/kernel/security/tomoyo/ users,
 * false otherwise.
 */
static bool tomoyo_name_used_by_io_buffer(const char *string)
{ … }

/**
 * tomoyo_del_transition_control - Delete members in "struct tomoyo_transition_control".
 *
 * @element: Pointer to "struct list_head".
 *
 * Returns nothing.
 */
static inline void tomoyo_del_transition_control(struct list_head *element)
{ … }

/**
 * tomoyo_del_aggregator - Delete members in "struct tomoyo_aggregator".
 *
 * @element: Pointer to "struct list_head".
 *
 * Returns nothing.
 */
static inline void tomoyo_del_aggregator(struct list_head *element)
{ … }

/**
 * tomoyo_del_manager - Delete members in "struct tomoyo_manager".
 *
 * @element: Pointer to "struct list_head".
 *
 * Returns nothing.
 */
static inline void tomoyo_del_manager(struct list_head *element)
{ … }

/**
 * tomoyo_del_acl - Delete members in "struct tomoyo_acl_info".
 *
 * @element: Pointer to "struct list_head".
 *
 * Returns nothing.
 */
static void tomoyo_del_acl(struct list_head *element)
{ … }

/**
 * tomoyo_del_domain - Delete members in "struct tomoyo_domain_info".
 *
 * @element: Pointer to "struct list_head".
 *
 * Returns nothing.
 *
 * Caller holds tomoyo_policy_lock mutex.
 */
static inline void tomoyo_del_domain(struct list_head *element)
{ … }

/**
 * tomoyo_del_condition - Delete members in "struct tomoyo_condition".
 *
 * @element: Pointer to "struct list_head".
 *
 * Returns nothing.
 */
void tomoyo_del_condition(struct list_head *element)
{ … }

/**
 * tomoyo_del_name - Delete members in "struct tomoyo_name".
 *
 * @element: Pointer to "struct list_head".
 *
 * Returns nothing.
 */
static inline void tomoyo_del_name(struct list_head *element)
{ … }

/**
 * tomoyo_del_path_group - Delete members in "struct tomoyo_path_group".
 *
 * @element: Pointer to "struct list_head".
 *
 * Returns nothing.
 */
static inline void tomoyo_del_path_group(struct list_head *element)
{ … }

/**
 * tomoyo_del_group - Delete "struct tomoyo_group".
 *
 * @element: Pointer to "struct list_head".
 *
 * Returns nothing.
 */
static inline void tomoyo_del_group(struct list_head *element)
{ … }

/**
 * tomoyo_del_address_group - Delete members in "struct tomoyo_address_group".
 *
 * @element: Pointer to "struct list_head".
 *
 * Returns nothing.
 */
static inline void tomoyo_del_address_group(struct list_head *element)
{ … }

/**
 * tomoyo_del_number_group - Delete members in "struct tomoyo_number_group".
 *
 * @element: Pointer to "struct list_head".
 *
 * Returns nothing.
 */
static inline void tomoyo_del_number_group(struct list_head *element)
{ … }

/**
 * tomoyo_try_to_gc - Try to kfree() an entry.
 *
 * @type:    One of values in "enum tomoyo_policy_id".
 * @element: Pointer to "struct list_head".
 *
 * Returns nothing.
 *
 * Caller holds tomoyo_policy_lock mutex.
 */
static void tomoyo_try_to_gc(const enum tomoyo_policy_id type,
			     struct list_head *element)
{ … }

/**
 * tomoyo_collect_member - Delete elements with "struct tomoyo_acl_head".
 *
 * @id:          One of values in "enum tomoyo_policy_id".
 * @member_list: Pointer to "struct list_head".
 *
 * Returns nothing.
 */
static void tomoyo_collect_member(const enum tomoyo_policy_id id,
				  struct list_head *member_list)
{ … }

/**
 * tomoyo_collect_acl - Delete elements in "struct tomoyo_domain_info".
 *
 * @list: Pointer to "struct list_head".
 *
 * Returns nothing.
 */
static void tomoyo_collect_acl(struct list_head *list)
{ … }

/**
 * tomoyo_collect_entry - Try to kfree() deleted elements.
 *
 * Returns nothing.
 */
static void tomoyo_collect_entry(void)
{ … }

/**
 * tomoyo_gc_thread - Garbage collector thread function.
 *
 * @unused: Unused.
 *
 * Returns 0.
 */
static int tomoyo_gc_thread(void *unused)
{ … }

/**
 * tomoyo_notify_gc - Register/unregister /sys/kernel/security/tomoyo/ users.
 *
 * @head:        Pointer to "struct tomoyo_io_buffer".
 * @is_register: True if register, false if unregister.
 *
 * Returns nothing.
 */
void tomoyo_notify_gc(struct tomoyo_io_buffer *head, const bool is_register)
{ … }