forked from mirrors/linux
		
	TOMOYO: Add garbage collector.
This patch adds garbage collector support to TOMOYO. Elements are protected by "struct srcu_struct tomoyo_ss". Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Acked-by: Serge Hallyn <serue@us.ibm.com> Signed-off-by: James Morris <jmorris@namei.org>
This commit is contained in:
		
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									ec8e6a4e06
								
							
						
					
					
						commit
						847b173ea3
					
				
					 7 changed files with 436 additions and 54 deletions
				
			
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			@ -1 +1 @@
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obj-y = common.o realpath.o tomoyo.o domain.o file.o
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obj-y = common.o realpath.o tomoyo.o domain.o file.o gc.o
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			@ -1067,7 +1067,7 @@ static int tomoyo_read_profile(struct tomoyo_io_buffer *head)
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 *
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 * # cat /sys/kernel/security/tomoyo/manager
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 */
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static LIST_HEAD(tomoyo_policy_manager_list);
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LIST_HEAD(tomoyo_policy_manager_list);
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/**
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 * tomoyo_update_manager_entry - Add a manager entry.
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			@ -2109,6 +2109,7 @@ static int tomoyo_write_control(struct file *file, const char __user *buffer,
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static int tomoyo_close_control(struct file *file)
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{
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	struct tomoyo_io_buffer *head = file->private_data;
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	const bool is_write = !!head->write_buf;
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	tomoyo_read_unlock(head->reader_idx);
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	/* Release memory used for policy I/O. */
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			@ -2119,6 +2120,8 @@ static int tomoyo_close_control(struct file *file)
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	kfree(head);
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	head = NULL;
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	file->private_data = NULL;
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	if (is_write)
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		tomoyo_run_gc();
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	return 0;
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}
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			@ -638,6 +638,11 @@ int tomoyo_check_rewrite_permission(struct tomoyo_domain_info *domain,
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				    struct file *filp);
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int tomoyo_find_next_domain(struct linux_binprm *bprm);
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/* Run garbage collector. */
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void tomoyo_run_gc(void);
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void tomoyo_memory_free(void *ptr);
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/********** External variable definitions. **********/
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/* Lock for GC. */
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			@ -646,6 +651,16 @@ extern struct srcu_struct tomoyo_ss;
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/* The list for "struct tomoyo_domain_info". */
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extern struct list_head tomoyo_domain_list;
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extern struct list_head tomoyo_domain_initializer_list;
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extern struct list_head tomoyo_domain_keeper_list;
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extern struct list_head tomoyo_alias_list;
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extern struct list_head tomoyo_globally_readable_list;
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extern struct list_head tomoyo_pattern_list;
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extern struct list_head tomoyo_no_rewrite_list;
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extern struct list_head tomoyo_policy_manager_list;
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extern struct list_head tomoyo_name_list[TOMOYO_MAX_HASH];
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extern struct mutex tomoyo_name_list_lock;
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/* Lock for protecting policy. */
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extern struct mutex tomoyo_policy_lock;
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			@ -110,7 +110,7 @@ const char *tomoyo_get_last_name(const struct tomoyo_domain_info *domain)
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 * will cause "/usr/sbin/httpd" to belong to "<kernel> /usr/sbin/httpd" domain
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 * unless executed from "<kernel> /etc/rc.d/init.d/httpd" domain.
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 */
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static LIST_HEAD(tomoyo_domain_initializer_list);
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LIST_HEAD(tomoyo_domain_initializer_list);
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/**
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 * tomoyo_update_domain_initializer_entry - Update "struct tomoyo_domain_initializer_entry" list.
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			@ -330,7 +330,7 @@ static bool tomoyo_is_domain_initializer(const struct tomoyo_path_info *
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 * "<kernel> /usr/sbin/sshd /bin/bash /usr/bin/passwd" domain, unless
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 * explicitly specified by "initialize_domain".
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 */
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static LIST_HEAD(tomoyo_domain_keeper_list);
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LIST_HEAD(tomoyo_domain_keeper_list);
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/**
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 * tomoyo_update_domain_keeper_entry - Update "struct tomoyo_domain_keeper_entry" list.
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			@ -533,7 +533,7 @@ static bool tomoyo_is_domain_keeper(const struct tomoyo_path_info *domainname,
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 * /bin/busybox and domainname which the current process will belong to after
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 * execve() succeeds is calculated using /bin/cat rather than /bin/busybox .
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 */
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static LIST_HEAD(tomoyo_alias_list);
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LIST_HEAD(tomoyo_alias_list);
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/**
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 * tomoyo_update_alias_entry - Update "struct tomoyo_alias_entry" list.
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			@ -148,7 +148,7 @@ static int tomoyo_update_single_path_acl(const u8 type, const char *filename,
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 * given "allow_read /lib/libc-2.5.so" to the domain which current process
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 * belongs to.
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 */
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static LIST_HEAD(tomoyo_globally_readable_list);
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LIST_HEAD(tomoyo_globally_readable_list);
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/**
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 * tomoyo_update_globally_readable_entry - Update "struct tomoyo_globally_readable_file_entry" list.
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			@ -295,7 +295,7 @@ bool tomoyo_read_globally_readable_policy(struct tomoyo_io_buffer *head)
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 * which pretends as if /proc/self/ is not a symlink; so that we can forbid
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 * current process from accessing other process's information.
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 */
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static LIST_HEAD(tomoyo_pattern_list);
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LIST_HEAD(tomoyo_pattern_list);
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/**
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 * tomoyo_update_file_pattern_entry - Update "struct tomoyo_pattern_entry" list.
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			@ -448,7 +448,7 @@ bool tomoyo_read_file_pattern(struct tomoyo_io_buffer *head)
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 * " (deleted)" suffix if the file is already unlink()ed; so that we don't
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 * need to worry whether the file is already unlink()ed or not.
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 */
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static LIST_HEAD(tomoyo_no_rewrite_list);
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LIST_HEAD(tomoyo_no_rewrite_list);
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/**
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 * tomoyo_update_no_rewrite_entry - Update "struct tomoyo_no_rewrite_entry" list.
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		|||
							
								
								
									
										370
									
								
								security/tomoyo/gc.c
									
									
									
									
									
										Normal file
									
								
							
							
						
						
									
										370
									
								
								security/tomoyo/gc.c
									
									
									
									
									
										Normal file
									
								
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			@ -0,0 +1,370 @@
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/*
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 * security/tomoyo/gc.c
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 *
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 * Implementation of the Domain-Based Mandatory Access Control.
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 *
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 * Copyright (C) 2005-2010  NTT DATA CORPORATION
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 *
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 */
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#include "common.h"
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#include <linux/kthread.h>
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enum tomoyo_gc_id {
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	TOMOYO_ID_DOMAIN_INITIALIZER,
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	TOMOYO_ID_DOMAIN_KEEPER,
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	TOMOYO_ID_ALIAS,
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	TOMOYO_ID_GLOBALLY_READABLE,
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	TOMOYO_ID_PATTERN,
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	TOMOYO_ID_NO_REWRITE,
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	TOMOYO_ID_MANAGER,
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	TOMOYO_ID_NAME,
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	TOMOYO_ID_ACL,
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	TOMOYO_ID_DOMAIN
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};
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struct tomoyo_gc_entry {
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	struct list_head list;
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	int type;
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	void *element;
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};
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static LIST_HEAD(tomoyo_gc_queue);
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static DEFINE_MUTEX(tomoyo_gc_mutex);
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/* Caller holds tomoyo_policy_lock mutex. */
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static bool tomoyo_add_to_gc(const int type, void *element)
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{
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	struct tomoyo_gc_entry *entry = kzalloc(sizeof(*entry), GFP_ATOMIC);
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	if (!entry)
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		return false;
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	entry->type = type;
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	entry->element = element;
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	list_add(&entry->list, &tomoyo_gc_queue);
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	return true;
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}
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static void tomoyo_del_allow_read
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(struct tomoyo_globally_readable_file_entry *ptr)
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{
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	tomoyo_put_name(ptr->filename);
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}
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static void tomoyo_del_file_pattern(struct tomoyo_pattern_entry *ptr)
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{
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	tomoyo_put_name(ptr->pattern);
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}
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static void tomoyo_del_no_rewrite(struct tomoyo_no_rewrite_entry *ptr)
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{
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	tomoyo_put_name(ptr->pattern);
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}
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static void tomoyo_del_domain_initializer
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(struct tomoyo_domain_initializer_entry *ptr)
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{
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	tomoyo_put_name(ptr->domainname);
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	tomoyo_put_name(ptr->program);
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}
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static void tomoyo_del_domain_keeper(struct tomoyo_domain_keeper_entry *ptr)
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{
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	tomoyo_put_name(ptr->domainname);
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	tomoyo_put_name(ptr->program);
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}
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static void tomoyo_del_alias(struct tomoyo_alias_entry *ptr)
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{
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	tomoyo_put_name(ptr->original_name);
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	tomoyo_put_name(ptr->aliased_name);
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}
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static void tomoyo_del_manager(struct tomoyo_policy_manager_entry *ptr)
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{
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	tomoyo_put_name(ptr->manager);
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}
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static void tomoyo_del_acl(struct tomoyo_acl_info *acl)
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{
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	switch (acl->type) {
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	case TOMOYO_TYPE_SINGLE_PATH_ACL:
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		{
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			struct tomoyo_single_path_acl_record *entry
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				= container_of(acl, typeof(*entry), head);
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			tomoyo_put_name(entry->filename);
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		}
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		break;
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	case TOMOYO_TYPE_DOUBLE_PATH_ACL:
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		{
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			struct tomoyo_double_path_acl_record *entry
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				= container_of(acl, typeof(*entry), head);
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			tomoyo_put_name(entry->filename1);
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			tomoyo_put_name(entry->filename2);
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		}
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		break;
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	default:
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		printk(KERN_WARNING "Unknown type\n");
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		break;
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	}
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}
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static bool tomoyo_del_domain(struct tomoyo_domain_info *domain)
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{
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	struct tomoyo_acl_info *acl;
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	struct tomoyo_acl_info *tmp;
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	/*
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	 * Since we don't protect whole execve() operation using SRCU,
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	 * we need to recheck domain->users at this point.
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	 *
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	 * (1) Reader starts SRCU section upon execve().
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	 * (2) Reader traverses tomoyo_domain_list and finds this domain.
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	 * (3) Writer marks this domain as deleted.
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	 * (4) Garbage collector removes this domain from tomoyo_domain_list
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	 *     because this domain is marked as deleted and used by nobody.
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	 * (5) Reader saves reference to this domain into
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	 *     "struct linux_binprm"->cred->security .
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	 * (6) Reader finishes SRCU section, although execve() operation has
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	 *     not finished yet.
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	 * (7) Garbage collector waits for SRCU synchronization.
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	 * (8) Garbage collector kfree() this domain because this domain is
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	 *     used by nobody.
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	 * (9) Reader finishes execve() operation and restores this domain from
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	 *     "struct linux_binprm"->cred->security.
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	 *
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	 * By updating domain->users at (5), we can solve this race problem
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	 * by rechecking domain->users at (8).
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	 */
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	if (atomic_read(&domain->users))
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		return false;
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	list_for_each_entry_safe(acl, tmp, &domain->acl_info_list, list) {
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		tomoyo_del_acl(acl);
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		tomoyo_memory_free(acl);
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	}
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	tomoyo_put_name(domain->domainname);
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	return true;
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}
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static void tomoyo_del_name(const struct tomoyo_name_entry *ptr)
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{
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}
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static void tomoyo_collect_entry(void)
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{
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	mutex_lock(&tomoyo_policy_lock);
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	{
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		struct tomoyo_globally_readable_file_entry *ptr;
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		list_for_each_entry_rcu(ptr, &tomoyo_globally_readable_list,
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					list) {
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			if (!ptr->is_deleted)
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				continue;
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			if (tomoyo_add_to_gc(TOMOYO_ID_GLOBALLY_READABLE, ptr))
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				list_del_rcu(&ptr->list);
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			else
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				break;
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		}
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	}
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	{
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		struct tomoyo_pattern_entry *ptr;
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		list_for_each_entry_rcu(ptr, &tomoyo_pattern_list, list) {
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			if (!ptr->is_deleted)
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				continue;
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			if (tomoyo_add_to_gc(TOMOYO_ID_PATTERN, ptr))
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				list_del_rcu(&ptr->list);
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			else
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				break;
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		}
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	}
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	{
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		struct tomoyo_no_rewrite_entry *ptr;
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		list_for_each_entry_rcu(ptr, &tomoyo_no_rewrite_list, list) {
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			if (!ptr->is_deleted)
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				continue;
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			if (tomoyo_add_to_gc(TOMOYO_ID_NO_REWRITE, ptr))
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				list_del_rcu(&ptr->list);
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			else
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				break;
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		}
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	}
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	{
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		struct tomoyo_domain_initializer_entry *ptr;
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		list_for_each_entry_rcu(ptr, &tomoyo_domain_initializer_list,
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					list) {
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			if (!ptr->is_deleted)
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				continue;
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			if (tomoyo_add_to_gc(TOMOYO_ID_DOMAIN_INITIALIZER, ptr))
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				list_del_rcu(&ptr->list);
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			else
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				break;
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		}
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	}
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	{
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		struct tomoyo_domain_keeper_entry *ptr;
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		list_for_each_entry_rcu(ptr, &tomoyo_domain_keeper_list, list) {
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			if (!ptr->is_deleted)
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				continue;
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			if (tomoyo_add_to_gc(TOMOYO_ID_DOMAIN_KEEPER, ptr))
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				list_del_rcu(&ptr->list);
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			else
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				break;
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		}
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	}
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	{
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		struct tomoyo_alias_entry *ptr;
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		list_for_each_entry_rcu(ptr, &tomoyo_alias_list, list) {
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			if (!ptr->is_deleted)
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				continue;
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			if (tomoyo_add_to_gc(TOMOYO_ID_ALIAS, ptr))
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				list_del_rcu(&ptr->list);
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			else
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				break;
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		}
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	}
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	{
 | 
			
		||||
		struct tomoyo_policy_manager_entry *ptr;
 | 
			
		||||
		list_for_each_entry_rcu(ptr, &tomoyo_policy_manager_list,
 | 
			
		||||
					list) {
 | 
			
		||||
			if (!ptr->is_deleted)
 | 
			
		||||
				continue;
 | 
			
		||||
			if (tomoyo_add_to_gc(TOMOYO_ID_MANAGER, ptr))
 | 
			
		||||
				list_del_rcu(&ptr->list);
 | 
			
		||||
			else
 | 
			
		||||
				break;
 | 
			
		||||
		}
 | 
			
		||||
	}
 | 
			
		||||
	{
 | 
			
		||||
		struct tomoyo_domain_info *domain;
 | 
			
		||||
		list_for_each_entry_rcu(domain, &tomoyo_domain_list, list) {
 | 
			
		||||
			struct tomoyo_acl_info *acl;
 | 
			
		||||
			list_for_each_entry_rcu(acl, &domain->acl_info_list,
 | 
			
		||||
						list) {
 | 
			
		||||
				switch (acl->type) {
 | 
			
		||||
				case TOMOYO_TYPE_SINGLE_PATH_ACL:
 | 
			
		||||
					if (container_of(acl,
 | 
			
		||||
					 struct tomoyo_single_path_acl_record,
 | 
			
		||||
							 head)->perm ||
 | 
			
		||||
					    container_of(acl,
 | 
			
		||||
					 struct tomoyo_single_path_acl_record,
 | 
			
		||||
							 head)->perm_high)
 | 
			
		||||
						continue;
 | 
			
		||||
					break;
 | 
			
		||||
				case TOMOYO_TYPE_DOUBLE_PATH_ACL:
 | 
			
		||||
					if (container_of(acl,
 | 
			
		||||
					 struct tomoyo_double_path_acl_record,
 | 
			
		||||
							 head)->perm)
 | 
			
		||||
						continue;
 | 
			
		||||
					break;
 | 
			
		||||
				default:
 | 
			
		||||
					continue;
 | 
			
		||||
				}
 | 
			
		||||
				if (tomoyo_add_to_gc(TOMOYO_ID_ACL, acl))
 | 
			
		||||
					list_del_rcu(&acl->list);
 | 
			
		||||
				else
 | 
			
		||||
					break;
 | 
			
		||||
			}
 | 
			
		||||
			if (!domain->is_deleted || atomic_read(&domain->users))
 | 
			
		||||
				continue;
 | 
			
		||||
			/*
 | 
			
		||||
			 * Nobody is referring this domain. But somebody may
 | 
			
		||||
			 * refer this domain after successful execve().
 | 
			
		||||
			 * We recheck domain->users after SRCU synchronization.
 | 
			
		||||
			 */
 | 
			
		||||
			if (tomoyo_add_to_gc(TOMOYO_ID_DOMAIN, domain))
 | 
			
		||||
				list_del_rcu(&domain->list);
 | 
			
		||||
			else
 | 
			
		||||
				break;
 | 
			
		||||
		}
 | 
			
		||||
	}
 | 
			
		||||
	mutex_unlock(&tomoyo_policy_lock);
 | 
			
		||||
	mutex_lock(&tomoyo_name_list_lock);
 | 
			
		||||
	{
 | 
			
		||||
		int i;
 | 
			
		||||
		for (i = 0; i < TOMOYO_MAX_HASH; i++) {
 | 
			
		||||
			struct tomoyo_name_entry *ptr;
 | 
			
		||||
			list_for_each_entry_rcu(ptr, &tomoyo_name_list[i],
 | 
			
		||||
						list) {
 | 
			
		||||
				if (atomic_read(&ptr->users))
 | 
			
		||||
					continue;
 | 
			
		||||
				if (tomoyo_add_to_gc(TOMOYO_ID_NAME, ptr))
 | 
			
		||||
					list_del_rcu(&ptr->list);
 | 
			
		||||
				else {
 | 
			
		||||
					i = TOMOYO_MAX_HASH;
 | 
			
		||||
					break;
 | 
			
		||||
				}
 | 
			
		||||
			}
 | 
			
		||||
		}
 | 
			
		||||
	}
 | 
			
		||||
	mutex_unlock(&tomoyo_name_list_lock);
 | 
			
		||||
}
 | 
			
		||||
 | 
			
		||||
static void tomoyo_kfree_entry(void)
 | 
			
		||||
{
 | 
			
		||||
	struct tomoyo_gc_entry *p;
 | 
			
		||||
	struct tomoyo_gc_entry *tmp;
 | 
			
		||||
 | 
			
		||||
	list_for_each_entry_safe(p, tmp, &tomoyo_gc_queue, list) {
 | 
			
		||||
		switch (p->type) {
 | 
			
		||||
		case TOMOYO_ID_DOMAIN_INITIALIZER:
 | 
			
		||||
			tomoyo_del_domain_initializer(p->element);
 | 
			
		||||
			break;
 | 
			
		||||
		case TOMOYO_ID_DOMAIN_KEEPER:
 | 
			
		||||
			tomoyo_del_domain_keeper(p->element);
 | 
			
		||||
			break;
 | 
			
		||||
		case TOMOYO_ID_ALIAS:
 | 
			
		||||
			tomoyo_del_alias(p->element);
 | 
			
		||||
			break;
 | 
			
		||||
		case TOMOYO_ID_GLOBALLY_READABLE:
 | 
			
		||||
			tomoyo_del_allow_read(p->element);
 | 
			
		||||
			break;
 | 
			
		||||
		case TOMOYO_ID_PATTERN:
 | 
			
		||||
			tomoyo_del_file_pattern(p->element);
 | 
			
		||||
			break;
 | 
			
		||||
		case TOMOYO_ID_NO_REWRITE:
 | 
			
		||||
			tomoyo_del_no_rewrite(p->element);
 | 
			
		||||
			break;
 | 
			
		||||
		case TOMOYO_ID_MANAGER:
 | 
			
		||||
			tomoyo_del_manager(p->element);
 | 
			
		||||
			break;
 | 
			
		||||
		case TOMOYO_ID_NAME:
 | 
			
		||||
			tomoyo_del_name(p->element);
 | 
			
		||||
			break;
 | 
			
		||||
		case TOMOYO_ID_ACL:
 | 
			
		||||
			tomoyo_del_acl(p->element);
 | 
			
		||||
			break;
 | 
			
		||||
		case TOMOYO_ID_DOMAIN:
 | 
			
		||||
			if (!tomoyo_del_domain(p->element))
 | 
			
		||||
				continue;
 | 
			
		||||
			break;
 | 
			
		||||
		default:
 | 
			
		||||
			printk(KERN_WARNING "Unknown type\n");
 | 
			
		||||
			break;
 | 
			
		||||
		}
 | 
			
		||||
		tomoyo_memory_free(p->element);
 | 
			
		||||
		list_del(&p->list);
 | 
			
		||||
		kfree(p);
 | 
			
		||||
	}
 | 
			
		||||
}
 | 
			
		||||
 | 
			
		||||
static int tomoyo_gc_thread(void *unused)
 | 
			
		||||
{
 | 
			
		||||
	daemonize("GC for TOMOYO");
 | 
			
		||||
	if (mutex_trylock(&tomoyo_gc_mutex)) {
 | 
			
		||||
		int i;
 | 
			
		||||
		for (i = 0; i < 10; i++) {
 | 
			
		||||
			tomoyo_collect_entry();
 | 
			
		||||
			if (list_empty(&tomoyo_gc_queue))
 | 
			
		||||
				break;
 | 
			
		||||
			synchronize_srcu(&tomoyo_ss);
 | 
			
		||||
			tomoyo_kfree_entry();
 | 
			
		||||
		}
 | 
			
		||||
		mutex_unlock(&tomoyo_gc_mutex);
 | 
			
		||||
	}
 | 
			
		||||
	do_exit(0);
 | 
			
		||||
}
 | 
			
		||||
 | 
			
		||||
void tomoyo_run_gc(void)
 | 
			
		||||
{
 | 
			
		||||
	struct task_struct *task = kthread_create(tomoyo_gc_thread, NULL,
 | 
			
		||||
						  "GC for TOMOYO");
 | 
			
		||||
	if (!IS_ERR(task))
 | 
			
		||||
		wake_up_process(task);
 | 
			
		||||
}
 | 
			
		||||
| 
						 | 
				
			
			@ -205,9 +205,9 @@ char *tomoyo_realpath_nofollow(const char *pathname)
 | 
			
		|||
}
 | 
			
		||||
 | 
			
		||||
/* Memory allocated for non-string data. */
 | 
			
		||||
static unsigned int tomoyo_allocated_memory_for_elements;
 | 
			
		||||
/* Quota for holding non-string data. */
 | 
			
		||||
static unsigned int tomoyo_quota_for_elements;
 | 
			
		||||
static atomic_t tomoyo_policy_memory_size;
 | 
			
		||||
/* Quota for holding policy. */
 | 
			
		||||
static unsigned int tomoyo_quota_for_policy;
 | 
			
		||||
 | 
			
		||||
/**
 | 
			
		||||
 * tomoyo_memory_ok - Check memory quota.
 | 
			
		||||
| 
						 | 
				
			
			@ -222,26 +222,30 @@ static unsigned int tomoyo_quota_for_elements;
 | 
			
		|||
bool tomoyo_memory_ok(void *ptr)
 | 
			
		||||
{
 | 
			
		||||
	int allocated_len = ptr ? ksize(ptr) : 0;
 | 
			
		||||
	bool result = false;
 | 
			
		||||
	if (!ptr || (tomoyo_quota_for_elements &&
 | 
			
		||||
		     tomoyo_allocated_memory_for_elements
 | 
			
		||||
		     + allocated_len > tomoyo_quota_for_elements)) {
 | 
			
		||||
	atomic_add(allocated_len, &tomoyo_policy_memory_size);
 | 
			
		||||
	if (ptr && (!tomoyo_quota_for_policy ||
 | 
			
		||||
		    atomic_read(&tomoyo_policy_memory_size)
 | 
			
		||||
		    <= tomoyo_quota_for_policy)) {
 | 
			
		||||
		memset(ptr, 0, allocated_len);
 | 
			
		||||
		return true;
 | 
			
		||||
	}
 | 
			
		||||
	printk(KERN_WARNING "ERROR: Out of memory "
 | 
			
		||||
	       "for tomoyo_alloc_element().\n");
 | 
			
		||||
	if (!tomoyo_policy_loaded)
 | 
			
		||||
		panic("MAC Initialization failed.\n");
 | 
			
		||||
	} else {
 | 
			
		||||
		result = true;
 | 
			
		||||
		tomoyo_allocated_memory_for_elements += allocated_len;
 | 
			
		||||
		memset(ptr, 0, allocated_len);
 | 
			
		||||
	}
 | 
			
		||||
	return result;
 | 
			
		||||
	return false;
 | 
			
		||||
}
 | 
			
		||||
 | 
			
		||||
/* Memory allocated for string data in bytes. */
 | 
			
		||||
static unsigned int tomoyo_allocated_memory_for_savename;
 | 
			
		||||
/* Quota for holding string data in bytes. */
 | 
			
		||||
static unsigned int tomoyo_quota_for_savename;
 | 
			
		||||
/**
 | 
			
		||||
 * tomoyo_memory_free - Free memory for elements.
 | 
			
		||||
 *
 | 
			
		||||
 * @ptr:  Pointer to allocated memory.
 | 
			
		||||
 */
 | 
			
		||||
void tomoyo_memory_free(void *ptr)
 | 
			
		||||
{
 | 
			
		||||
	atomic_sub(ksize(ptr), &tomoyo_policy_memory_size);
 | 
			
		||||
	kfree(ptr);
 | 
			
		||||
}
 | 
			
		||||
 | 
			
		||||
/*
 | 
			
		||||
 * tomoyo_name_list is used for holding string data used by TOMOYO.
 | 
			
		||||
| 
						 | 
				
			
			@ -249,7 +253,9 @@ static unsigned int tomoyo_quota_for_savename;
 | 
			
		|||
 * "/lib/libc-2.5.so"), TOMOYO shares string data in the form of
 | 
			
		||||
 * "const struct tomoyo_path_info *".
 | 
			
		||||
 */
 | 
			
		||||
static struct list_head tomoyo_name_list[TOMOYO_MAX_HASH];
 | 
			
		||||
struct list_head tomoyo_name_list[TOMOYO_MAX_HASH];
 | 
			
		||||
/* Lock for protecting tomoyo_name_list . */
 | 
			
		||||
DEFINE_MUTEX(tomoyo_name_list_lock);
 | 
			
		||||
 | 
			
		||||
/**
 | 
			
		||||
 * tomoyo_get_name - Allocate permanent memory for string data.
 | 
			
		||||
| 
						 | 
				
			
			@ -260,7 +266,6 @@ static struct list_head tomoyo_name_list[TOMOYO_MAX_HASH];
 | 
			
		|||
 */
 | 
			
		||||
const struct tomoyo_path_info *tomoyo_get_name(const char *name)
 | 
			
		||||
{
 | 
			
		||||
	static DEFINE_MUTEX(lock);
 | 
			
		||||
	struct tomoyo_name_entry *ptr;
 | 
			
		||||
	unsigned int hash;
 | 
			
		||||
	int len;
 | 
			
		||||
| 
						 | 
				
			
			@ -272,7 +277,7 @@ const struct tomoyo_path_info *tomoyo_get_name(const char *name)
 | 
			
		|||
	len = strlen(name) + 1;
 | 
			
		||||
	hash = full_name_hash((const unsigned char *) name, len - 1);
 | 
			
		||||
	head = &tomoyo_name_list[hash_long(hash, TOMOYO_HASH_BITS)];
 | 
			
		||||
	mutex_lock(&lock);
 | 
			
		||||
	mutex_lock(&tomoyo_name_list_lock);
 | 
			
		||||
	list_for_each_entry(ptr, head, list) {
 | 
			
		||||
		if (hash != ptr->entry.hash || strcmp(name, ptr->entry.name))
 | 
			
		||||
			continue;
 | 
			
		||||
| 
						 | 
				
			
			@ -281,9 +286,9 @@ const struct tomoyo_path_info *tomoyo_get_name(const char *name)
 | 
			
		|||
	}
 | 
			
		||||
	ptr = kzalloc(sizeof(*ptr) + len, GFP_KERNEL);
 | 
			
		||||
	allocated_len = ptr ? ksize(ptr) : 0;
 | 
			
		||||
	if (!ptr || (tomoyo_quota_for_savename &&
 | 
			
		||||
		     tomoyo_allocated_memory_for_savename + allocated_len
 | 
			
		||||
		     > tomoyo_quota_for_savename)) {
 | 
			
		||||
	if (!ptr || (tomoyo_quota_for_policy &&
 | 
			
		||||
		     atomic_read(&tomoyo_policy_memory_size) + allocated_len
 | 
			
		||||
		     > tomoyo_quota_for_policy)) {
 | 
			
		||||
		kfree(ptr);
 | 
			
		||||
		printk(KERN_WARNING "ERROR: Out of memory "
 | 
			
		||||
		       "for tomoyo_get_name().\n");
 | 
			
		||||
| 
						 | 
				
			
			@ -292,14 +297,14 @@ const struct tomoyo_path_info *tomoyo_get_name(const char *name)
 | 
			
		|||
		ptr = NULL;
 | 
			
		||||
		goto out;
 | 
			
		||||
	}
 | 
			
		||||
	tomoyo_allocated_memory_for_savename += allocated_len;
 | 
			
		||||
	atomic_add(allocated_len, &tomoyo_policy_memory_size);
 | 
			
		||||
	ptr->entry.name = ((char *) ptr) + sizeof(*ptr);
 | 
			
		||||
	memmove((char *) ptr->entry.name, name, len);
 | 
			
		||||
	atomic_set(&ptr->users, 1);
 | 
			
		||||
	tomoyo_fill_path_info(&ptr->entry);
 | 
			
		||||
	list_add_tail(&ptr->list, head);
 | 
			
		||||
 out:
 | 
			
		||||
	mutex_unlock(&lock);
 | 
			
		||||
	mutex_unlock(&tomoyo_name_list_lock);
 | 
			
		||||
	return ptr ? &ptr->entry : NULL;
 | 
			
		||||
}
 | 
			
		||||
 | 
			
		||||
| 
						 | 
				
			
			@ -334,28 +339,19 @@ void __init tomoyo_realpath_init(void)
 | 
			
		|||
int tomoyo_read_memory_counter(struct tomoyo_io_buffer *head)
 | 
			
		||||
{
 | 
			
		||||
	if (!head->read_eof) {
 | 
			
		||||
		const unsigned int shared
 | 
			
		||||
			= tomoyo_allocated_memory_for_savename;
 | 
			
		||||
		const unsigned int private
 | 
			
		||||
			= tomoyo_allocated_memory_for_elements;
 | 
			
		||||
		const unsigned int policy
 | 
			
		||||
			= atomic_read(&tomoyo_policy_memory_size);
 | 
			
		||||
		char buffer[64];
 | 
			
		||||
 | 
			
		||||
		memset(buffer, 0, sizeof(buffer));
 | 
			
		||||
		if (tomoyo_quota_for_savename)
 | 
			
		||||
		if (tomoyo_quota_for_policy)
 | 
			
		||||
			snprintf(buffer, sizeof(buffer) - 1,
 | 
			
		||||
				 "   (Quota: %10u)",
 | 
			
		||||
				 tomoyo_quota_for_savename);
 | 
			
		||||
				 tomoyo_quota_for_policy);
 | 
			
		||||
		else
 | 
			
		||||
			buffer[0] = '\0';
 | 
			
		||||
		tomoyo_io_printf(head, "Shared:  %10u%s\n", shared, buffer);
 | 
			
		||||
		if (tomoyo_quota_for_elements)
 | 
			
		||||
			snprintf(buffer, sizeof(buffer) - 1,
 | 
			
		||||
				 "   (Quota: %10u)",
 | 
			
		||||
				 tomoyo_quota_for_elements);
 | 
			
		||||
		else
 | 
			
		||||
			buffer[0] = '\0';
 | 
			
		||||
		tomoyo_io_printf(head, "Private: %10u%s\n", private, buffer);
 | 
			
		||||
		tomoyo_io_printf(head, "Total:   %10u\n", shared + private);
 | 
			
		||||
		tomoyo_io_printf(head, "Policy:  %10u%s\n", policy, buffer);
 | 
			
		||||
		tomoyo_io_printf(head, "Total:   %10u\n", policy);
 | 
			
		||||
		head->read_eof = true;
 | 
			
		||||
	}
 | 
			
		||||
	return 0;
 | 
			
		||||
| 
						 | 
				
			
			@ -373,9 +369,7 @@ int tomoyo_write_memory_quota(struct tomoyo_io_buffer *head)
 | 
			
		|||
	char *data = head->write_buf;
 | 
			
		||||
	unsigned int size;
 | 
			
		||||
 | 
			
		||||
	if (sscanf(data, "Shared: %u", &size) == 1)
 | 
			
		||||
		tomoyo_quota_for_savename = size;
 | 
			
		||||
	else if (sscanf(data, "Private: %u", &size) == 1)
 | 
			
		||||
		tomoyo_quota_for_elements = size;
 | 
			
		||||
	if (sscanf(data, "Policy: %u", &size) == 1)
 | 
			
		||||
		tomoyo_quota_for_policy = size;
 | 
			
		||||
	return 0;
 | 
			
		||||
}
 | 
			
		||||
| 
						 | 
				
			
			
 | 
			
		|||
		Loading…
	
		Reference in a new issue