summaryrefslogtreecommitdiffstats
path: root/security/tomoyo/memory.c
diff options
context:
space:
mode:
Diffstat (limited to 'security/tomoyo/memory.c')
-rw-r--r--security/tomoyo/memory.c207
1 files changed, 207 insertions, 0 deletions
diff --git a/security/tomoyo/memory.c b/security/tomoyo/memory.c
new file mode 100644
index 000000000..2e7fcfa92
--- /dev/null
+++ b/security/tomoyo/memory.c
@@ -0,0 +1,207 @@
+// 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 = &param->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);
+}