aboutsummaryrefslogtreecommitdiff
path: root/security/tomoyo/memory.c
diff options
context:
space:
mode:
authorTetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>2010-05-17 10:12:46 +0900
committerJames Morris <jmorris@namei.org>2010-08-02 15:33:39 +1000
commitc3ef1500ec833890275172c7d063333404b64d60 (patch)
tree2453368e521a1f7a00098eef06afbedb8404503d /security/tomoyo/memory.c
parent17fcfbd9d45b57f38d40e31f9d28db53f4af5c88 (diff)
downloadlinux-linaro-stable-c3ef1500ec833890275172c7d063333404b64d60.tar.gz
TOMOYO: Split files into some pieces.
security/tomoyo/common.c became too large to read. Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp> Signed-off-by: James Morris <jmorris@namei.org>
Diffstat (limited to 'security/tomoyo/memory.c')
-rw-r--r--security/tomoyo/memory.c236
1 files changed, 236 insertions, 0 deletions
diff --git a/security/tomoyo/memory.c b/security/tomoyo/memory.c
new file mode 100644
index 000000000000..8fb73ff5cb63
--- /dev/null
+++ b/security/tomoyo/memory.c
@@ -0,0 +1,236 @@
+/*
+ * security/tomoyo/memory.c
+ *
+ * Memory management functions for TOMOYO.
+ *
+ * Copyright (C) 2005-2010 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) {
+ printk(KERN_WARNING "ERROR: Out of memory at %s.\n",
+ function);
+ tomoyo_last_pid = pid;
+ }
+ if (!tomoyo_policy_loaded)
+ panic("MAC Initialization failed.\n");
+}
+
+/* Memory allocated for policy. */
+static atomic_t tomoyo_policy_memory_size;
+/* Quota for holding policy. */
+static unsigned int tomoyo_quota_for_policy;
+
+/**
+ * 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.
+ */
+bool tomoyo_memory_ok(void *ptr)
+{
+ size_t s = ptr ? ksize(ptr) : 0;
+ atomic_add(s, &tomoyo_policy_memory_size);
+ if (ptr && (!tomoyo_quota_for_policy ||
+ atomic_read(&tomoyo_policy_memory_size)
+ <= tomoyo_quota_for_policy)) {
+ memset(ptr, 0, s);
+ return true;
+ }
+ atomic_sub(s, &tomoyo_policy_memory_size);
+ 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.
+ */
+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;
+ }
+ return NULL;
+}
+
+/**
+ * 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.
+ * 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_entry *ptr;
+ unsigned int hash;
+ int len;
+ int allocated_len;
+ struct list_head *head;
+
+ if (!name)
+ return NULL;
+ len = strlen(name) + 1;
+ hash = full_name_hash((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, list) {
+ if (hash != ptr->entry.hash || strcmp(name, ptr->entry.name))
+ continue;
+ atomic_inc(&ptr->users);
+ goto out;
+ }
+ ptr = kzalloc(sizeof(*ptr) + len, GFP_NOFS);
+ allocated_len = ptr ? ksize(ptr) : 0;
+ if (!ptr || (tomoyo_quota_for_policy &&
+ atomic_read(&tomoyo_policy_memory_size) + allocated_len
+ > tomoyo_quota_for_policy)) {
+ kfree(ptr);
+ ptr = NULL;
+ tomoyo_warn_oom(__func__);
+ goto out;
+ }
+ 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(&tomoyo_policy_lock);
+ return ptr ? &ptr->entry : NULL;
+}
+
+/**
+ * tomoyo_mm_init - Initialize mm related code.
+ */
+void __init tomoyo_mm_init(void)
+{
+ int idx;
+
+ BUILD_BUG_ON(TOMOYO_MAX_PATHNAME_LEN > PATH_MAX);
+ for (idx = 0; idx < TOMOYO_MAX_HASH; idx++)
+ INIT_LIST_HEAD(&tomoyo_name_list[idx]);
+ INIT_LIST_HEAD(&tomoyo_kernel_domain.acl_info_list);
+ tomoyo_kernel_domain.domainname = tomoyo_get_name(TOMOYO_ROOT_NAME);
+ list_add_tail_rcu(&tomoyo_kernel_domain.list, &tomoyo_domain_list);
+ idx = tomoyo_read_lock();
+ if (tomoyo_find_domain(TOMOYO_ROOT_NAME) != &tomoyo_kernel_domain)
+ panic("Can't register tomoyo_kernel_domain");
+ {
+ /* Load built-in policy. */
+ tomoyo_write_domain_initializer_policy("/sbin/hotplug",
+ false, false);
+ tomoyo_write_domain_initializer_policy("/sbin/modprobe",
+ false, false);
+ }
+ tomoyo_read_unlock(idx);
+}
+
+
+/* Memory allocated for query lists. */
+unsigned int tomoyo_query_memory_size;
+/* Quota for holding query lists. */
+unsigned int tomoyo_quota_for_query;
+
+/**
+ * tomoyo_read_memory_counter - Check for memory usage in bytes.
+ *
+ * @head: Pointer to "struct tomoyo_io_buffer".
+ *
+ * Returns memory usage.
+ */
+int tomoyo_read_memory_counter(struct tomoyo_io_buffer *head)
+{
+ if (!head->read_eof) {
+ const unsigned int policy
+ = atomic_read(&tomoyo_policy_memory_size);
+ const unsigned int query = tomoyo_query_memory_size;
+ char buffer[64];
+
+ memset(buffer, 0, sizeof(buffer));
+ if (tomoyo_quota_for_policy)
+ snprintf(buffer, sizeof(buffer) - 1,
+ " (Quota: %10u)",
+ tomoyo_quota_for_policy);
+ else
+ buffer[0] = '\0';
+ tomoyo_io_printf(head, "Policy: %10u%s\n", policy,
+ buffer);
+ if (tomoyo_quota_for_query)
+ snprintf(buffer, sizeof(buffer) - 1,
+ " (Quota: %10u)",
+ tomoyo_quota_for_query);
+ else
+ buffer[0] = '\0';
+ tomoyo_io_printf(head, "Query lists: %10u%s\n", query,
+ buffer);
+ tomoyo_io_printf(head, "Total: %10u\n", policy + query);
+ head->read_eof = true;
+ }
+ return 0;
+}
+
+/**
+ * tomoyo_write_memory_quota - Set memory quota.
+ *
+ * @head: Pointer to "struct tomoyo_io_buffer".
+ *
+ * Returns 0.
+ */
+int tomoyo_write_memory_quota(struct tomoyo_io_buffer *head)
+{
+ char *data = head->write_buf;
+ unsigned int size;
+
+ if (sscanf(data, "Policy: %u", &size) == 1)
+ tomoyo_quota_for_policy = size;
+ else if (sscanf(data, "Query lists: %u", &size) == 1)
+ tomoyo_quota_for_query = size;
+ return 0;
+}