// SPDX-License-Identifier: GPL-2.0
|
/*
|
* security/tomoyo/memory.c
|
*
|
* Copyright (C) 2005-2011 NTT DATA CORPORATION
|
*/
|
|
#include <linux/hash.h>
|
#include <linux/slab.h>
|
#include "common.h"
|
|
/**
|
* tomoyo_warn_oom - Print out of memory warning message.
|
*
|
* @function: Function's name.
|
*/
|
void tomoyo_warn_oom(const char *function)
|
{
|
/* Reduce error messages. */
|
static pid_t tomoyo_last_pid;
|
const pid_t pid = current->pid;
|
|
if (tomoyo_last_pid != pid) {
|
pr_warn("ERROR: Out of memory at %s.\n", function);
|
tomoyo_last_pid = pid;
|
}
|
if (!tomoyo_policy_loaded)
|
panic("MAC Initialization failed.\n");
|
}
|
|
/* Memoy currently used by policy/audit log/query. */
|
unsigned int tomoyo_memory_used[TOMOYO_MAX_MEMORY_STAT];
|
/* Memory quota for "policy"/"audit log"/"query". */
|
unsigned int tomoyo_memory_quota[TOMOYO_MAX_MEMORY_STAT];
|
|
/**
|
* tomoyo_memory_ok - Check memory quota.
|
*
|
* @ptr: Pointer to allocated memory.
|
*
|
* Returns true on success, false otherwise.
|
*
|
* Returns true if @ptr is not NULL and quota not exceeded, false otherwise.
|
*
|
* Caller holds tomoyo_policy_lock mutex.
|
*/
|
bool tomoyo_memory_ok(void *ptr)
|
{
|
if (ptr) {
|
const size_t s = ksize(ptr);
|
|
tomoyo_memory_used[TOMOYO_MEMORY_POLICY] += s;
|
if (!tomoyo_memory_quota[TOMOYO_MEMORY_POLICY] ||
|
tomoyo_memory_used[TOMOYO_MEMORY_POLICY] <=
|
tomoyo_memory_quota[TOMOYO_MEMORY_POLICY])
|
return true;
|
tomoyo_memory_used[TOMOYO_MEMORY_POLICY] -= s;
|
}
|
tomoyo_warn_oom(__func__);
|
return false;
|
}
|
|
/**
|
* tomoyo_commit_ok - Check memory quota.
|
*
|
* @data: Data to copy from.
|
* @size: Size in byte.
|
*
|
* Returns pointer to allocated memory on success, NULL otherwise.
|
* @data is zero-cleared on success.
|
*
|
* Caller holds tomoyo_policy_lock mutex.
|
*/
|
void *tomoyo_commit_ok(void *data, const unsigned int size)
|
{
|
void *ptr = kzalloc(size, GFP_NOFS);
|
|
if (tomoyo_memory_ok(ptr)) {
|
memmove(ptr, data, size);
|
memset(data, 0, size);
|
return ptr;
|
}
|
kfree(ptr);
|
return NULL;
|
}
|
|
/**
|
* tomoyo_get_group - Allocate memory for "struct tomoyo_path_group"/"struct tomoyo_number_group".
|
*
|
* @param: Pointer to "struct tomoyo_acl_param".
|
* @idx: Index number.
|
*
|
* Returns pointer to "struct tomoyo_group" on success, NULL otherwise.
|
*/
|
struct tomoyo_group *tomoyo_get_group(struct tomoyo_acl_param *param,
|
const u8 idx)
|
{
|
struct tomoyo_group e = { };
|
struct tomoyo_group *group = NULL;
|
struct list_head *list;
|
const char *group_name = tomoyo_read_token(param);
|
bool found = false;
|
|
if (!tomoyo_correct_word(group_name) || idx >= TOMOYO_MAX_GROUP)
|
return NULL;
|
e.group_name = tomoyo_get_name(group_name);
|
if (!e.group_name)
|
return NULL;
|
if (mutex_lock_interruptible(&tomoyo_policy_lock))
|
goto out;
|
list = ¶m->ns->group_list[idx];
|
list_for_each_entry(group, list, head.list) {
|
if (e.group_name != group->group_name ||
|
atomic_read(&group->head.users) == TOMOYO_GC_IN_PROGRESS)
|
continue;
|
atomic_inc(&group->head.users);
|
found = true;
|
break;
|
}
|
if (!found) {
|
struct tomoyo_group *entry = tomoyo_commit_ok(&e, sizeof(e));
|
|
if (entry) {
|
INIT_LIST_HEAD(&entry->member_list);
|
atomic_set(&entry->head.users, 1);
|
list_add_tail_rcu(&entry->head.list, list);
|
group = entry;
|
found = true;
|
}
|
}
|
mutex_unlock(&tomoyo_policy_lock);
|
out:
|
tomoyo_put_name(e.group_name);
|
return found ? group : NULL;
|
}
|
|
/*
|
* tomoyo_name_list is used for holding string data used by TOMOYO.
|
* Since same string data is likely used for multiple times (e.g.
|
* "/lib/libc-2.5.so"), TOMOYO shares string data in the form of
|
* "const struct tomoyo_path_info *".
|
*/
|
struct list_head tomoyo_name_list[TOMOYO_MAX_HASH];
|
|
/**
|
* tomoyo_get_name - Allocate permanent memory for string data.
|
*
|
* @name: The string to store into the permernent memory.
|
*
|
* Returns pointer to "struct tomoyo_path_info" on success, NULL otherwise.
|
*/
|
const struct tomoyo_path_info *tomoyo_get_name(const char *name)
|
{
|
struct tomoyo_name *ptr;
|
unsigned int hash;
|
int len;
|
struct list_head *head;
|
|
if (!name)
|
return NULL;
|
len = strlen(name) + 1;
|
hash = full_name_hash(NULL, (const unsigned char *) name, len - 1);
|
head = &tomoyo_name_list[hash_long(hash, TOMOYO_HASH_BITS)];
|
if (mutex_lock_interruptible(&tomoyo_policy_lock))
|
return NULL;
|
list_for_each_entry(ptr, head, head.list) {
|
if (hash != ptr->entry.hash || strcmp(name, ptr->entry.name) ||
|
atomic_read(&ptr->head.users) == TOMOYO_GC_IN_PROGRESS)
|
continue;
|
atomic_inc(&ptr->head.users);
|
goto out;
|
}
|
ptr = kzalloc(sizeof(*ptr) + len, GFP_NOFS);
|
if (tomoyo_memory_ok(ptr)) {
|
ptr->entry.name = ((char *) ptr) + sizeof(*ptr);
|
memmove((char *) ptr->entry.name, name, len);
|
atomic_set(&ptr->head.users, 1);
|
tomoyo_fill_path_info(&ptr->entry);
|
list_add_tail(&ptr->head.list, head);
|
} else {
|
kfree(ptr);
|
ptr = NULL;
|
}
|
out:
|
mutex_unlock(&tomoyo_policy_lock);
|
return ptr ? &ptr->entry : NULL;
|
}
|
|
/* Initial namespace.*/
|
struct tomoyo_policy_namespace tomoyo_kernel_namespace;
|
|
/**
|
* tomoyo_mm_init - Initialize mm related code.
|
*/
|
void __init tomoyo_mm_init(void)
|
{
|
int idx;
|
|
for (idx = 0; idx < TOMOYO_MAX_HASH; idx++)
|
INIT_LIST_HEAD(&tomoyo_name_list[idx]);
|
tomoyo_kernel_namespace.name = "<kernel>";
|
tomoyo_init_policy_namespace(&tomoyo_kernel_namespace);
|
tomoyo_kernel_domain.ns = &tomoyo_kernel_namespace;
|
INIT_LIST_HEAD(&tomoyo_kernel_domain.acl_info_list);
|
tomoyo_kernel_domain.domainname = tomoyo_get_name("<kernel>");
|
list_add_tail_rcu(&tomoyo_kernel_domain.list, &tomoyo_domain_list);
|
}
|
