]> bbs.cooldavid.org Git - net-next-2.6.git/blobdiff - security/tomoyo/domain.c
TOMOYO: Remove usage counter for temporary memory.
[net-next-2.6.git] / security / tomoyo / domain.c
index fcf52accce2b107798b7be675337eb53f9279a38..34843971cc60b279561ca743fd8ef97043934da0 100644 (file)
@@ -58,7 +58,6 @@ struct tomoyo_domain_info tomoyo_kernel_domain;
  * exceptions.
  */
 LIST_HEAD(tomoyo_domain_list);
-DECLARE_RWSEM(tomoyo_domain_list_lock);
 
 /*
  * tomoyo_domain_initializer_entry is a structure which is used for holding
@@ -206,7 +205,6 @@ const char *tomoyo_get_last_name(const struct tomoyo_domain_info *domain)
  * unless executed from "<kernel> /etc/rc.d/init.d/httpd" domain.
  */
 static LIST_HEAD(tomoyo_domain_initializer_list);
-static DECLARE_RWSEM(tomoyo_domain_initializer_list_lock);
 
 /**
  * tomoyo_update_domain_initializer_entry - Update "struct tomoyo_domain_initializer_entry" list.
@@ -217,6 +215,8 @@ static DECLARE_RWSEM(tomoyo_domain_initializer_list_lock);
  * @is_delete:  True if it is a delete request.
  *
  * Returns 0 on success, negative value otherwise.
+ *
+ * Caller holds tomoyo_read_lock().
  */
 static int tomoyo_update_domain_initializer_entry(const char *domainname,
                                                  const char *program,
@@ -245,8 +245,9 @@ static int tomoyo_update_domain_initializer_entry(const char *domainname,
        saved_program = tomoyo_save_name(program);
        if (!saved_program)
                return -ENOMEM;
-       down_write(&tomoyo_domain_initializer_list_lock);
-       list_for_each_entry(ptr, &tomoyo_domain_initializer_list, list) {
+       new_entry = kmalloc(sizeof(*new_entry), GFP_KERNEL);
+       mutex_lock(&tomoyo_policy_lock);
+       list_for_each_entry_rcu(ptr, &tomoyo_domain_initializer_list, list) {
                if (ptr->is_not != is_not ||
                    ptr->domainname != saved_domainname ||
                    ptr->program != saved_program)
@@ -259,17 +260,18 @@ static int tomoyo_update_domain_initializer_entry(const char *domainname,
                error = -ENOENT;
                goto out;
        }
-       new_entry = tomoyo_alloc_element(sizeof(*new_entry));
-       if (!new_entry)
+       if (!tomoyo_memory_ok(new_entry))
                goto out;
        new_entry->domainname = saved_domainname;
        new_entry->program = saved_program;
        new_entry->is_not = is_not;
        new_entry->is_last_name = is_last_name;
-       list_add_tail(&new_entry->list, &tomoyo_domain_initializer_list);
+       list_add_tail_rcu(&new_entry->list, &tomoyo_domain_initializer_list);
+       new_entry = NULL;
        error = 0;
  out:
-       up_write(&tomoyo_domain_initializer_list_lock);
+       mutex_unlock(&tomoyo_policy_lock);
+       kfree(new_entry);
        return error;
 }
 
@@ -279,13 +281,14 @@ static int tomoyo_update_domain_initializer_entry(const char *domainname,
  * @head: Pointer to "struct tomoyo_io_buffer".
  *
  * Returns true on success, false otherwise.
+ *
+ * Caller holds tomoyo_read_lock().
  */
 bool tomoyo_read_domain_initializer_policy(struct tomoyo_io_buffer *head)
 {
        struct list_head *pos;
        bool done = true;
 
-       down_read(&tomoyo_domain_initializer_list_lock);
        list_for_each_cookie(pos, head->read_var2,
                             &tomoyo_domain_initializer_list) {
                const char *no;
@@ -308,7 +311,6 @@ bool tomoyo_read_domain_initializer_policy(struct tomoyo_io_buffer *head)
                if (!done)
                        break;
        }
-       up_read(&tomoyo_domain_initializer_list_lock);
        return done;
 }
 
@@ -320,6 +322,8 @@ bool tomoyo_read_domain_initializer_policy(struct tomoyo_io_buffer *head)
  * @is_delete: True if it is a delete request.
  *
  * Returns 0 on success, negative value otherwise.
+ *
+ * Caller holds tomoyo_read_lock().
  */
 int tomoyo_write_domain_initializer_policy(char *data, const bool is_not,
                                           const bool is_delete)
@@ -345,6 +349,8 @@ int tomoyo_write_domain_initializer_policy(char *data, const bool is_not,
  *
  * Returns true if executing @program reinitializes domain transition,
  * false otherwise.
+ *
+ * Caller holds tomoyo_read_lock().
  */
 static bool tomoyo_is_domain_initializer(const struct tomoyo_path_info *
                                         domainname,
@@ -355,8 +361,7 @@ static bool tomoyo_is_domain_initializer(const struct tomoyo_path_info *
        struct tomoyo_domain_initializer_entry *ptr;
        bool flag = false;
 
-       down_read(&tomoyo_domain_initializer_list_lock);
-       list_for_each_entry(ptr,  &tomoyo_domain_initializer_list, list) {
+       list_for_each_entry_rcu(ptr, &tomoyo_domain_initializer_list, list) {
                if (ptr->is_deleted)
                        continue;
                if (ptr->domainname) {
@@ -376,7 +381,6 @@ static bool tomoyo_is_domain_initializer(const struct tomoyo_path_info *
                }
                flag = true;
        }
-       up_read(&tomoyo_domain_initializer_list_lock);
        return flag;
 }
 
@@ -419,7 +423,6 @@ static bool tomoyo_is_domain_initializer(const struct tomoyo_path_info *
  * explicitly specified by "initialize_domain".
  */
 static LIST_HEAD(tomoyo_domain_keeper_list);
-static DECLARE_RWSEM(tomoyo_domain_keeper_list_lock);
 
 /**
  * tomoyo_update_domain_keeper_entry - Update "struct tomoyo_domain_keeper_entry" list.
@@ -430,6 +433,8 @@ static DECLARE_RWSEM(tomoyo_domain_keeper_list_lock);
  * @is_delete:  True if it is a delete request.
  *
  * Returns 0 on success, negative value otherwise.
+ *
+ * Caller holds tomoyo_read_lock().
  */
 static int tomoyo_update_domain_keeper_entry(const char *domainname,
                                             const char *program,
@@ -458,8 +463,9 @@ static int tomoyo_update_domain_keeper_entry(const char *domainname,
        saved_domainname = tomoyo_save_name(domainname);
        if (!saved_domainname)
                return -ENOMEM;
-       down_write(&tomoyo_domain_keeper_list_lock);
-       list_for_each_entry(ptr, &tomoyo_domain_keeper_list, list) {
+       new_entry = kmalloc(sizeof(*new_entry), GFP_KERNEL);
+       mutex_lock(&tomoyo_policy_lock);
+       list_for_each_entry_rcu(ptr, &tomoyo_domain_keeper_list, list) {
                if (ptr->is_not != is_not ||
                    ptr->domainname != saved_domainname ||
                    ptr->program != saved_program)
@@ -472,17 +478,18 @@ static int tomoyo_update_domain_keeper_entry(const char *domainname,
                error = -ENOENT;
                goto out;
        }
-       new_entry = tomoyo_alloc_element(sizeof(*new_entry));
-       if (!new_entry)
+       if (!tomoyo_memory_ok(new_entry))
                goto out;
        new_entry->domainname = saved_domainname;
        new_entry->program = saved_program;
        new_entry->is_not = is_not;
        new_entry->is_last_name = is_last_name;
-       list_add_tail(&new_entry->list, &tomoyo_domain_keeper_list);
+       list_add_tail_rcu(&new_entry->list, &tomoyo_domain_keeper_list);
+       new_entry = NULL;
        error = 0;
  out:
-       up_write(&tomoyo_domain_keeper_list_lock);
+       mutex_unlock(&tomoyo_policy_lock);
+       kfree(new_entry);
        return error;
 }
 
@@ -493,6 +500,7 @@ static int tomoyo_update_domain_keeper_entry(const char *domainname,
  * @is_not:    True if it is "no_keep_domain" entry.
  * @is_delete: True if it is a delete request.
  *
+ * Caller holds tomoyo_read_lock().
  */
 int tomoyo_write_domain_keeper_policy(char *data, const bool is_not,
                                      const bool is_delete)
@@ -513,13 +521,14 @@ int tomoyo_write_domain_keeper_policy(char *data, const bool is_not,
  * @head: Pointer to "struct tomoyo_io_buffer".
  *
  * Returns true on success, false otherwise.
+ *
+ * Caller holds tomoyo_read_lock().
  */
 bool tomoyo_read_domain_keeper_policy(struct tomoyo_io_buffer *head)
 {
        struct list_head *pos;
        bool done = true;
 
-       down_read(&tomoyo_domain_keeper_list_lock);
        list_for_each_cookie(pos, head->read_var2,
                             &tomoyo_domain_keeper_list) {
                struct tomoyo_domain_keeper_entry *ptr;
@@ -542,7 +551,6 @@ bool tomoyo_read_domain_keeper_policy(struct tomoyo_io_buffer *head)
                if (!done)
                        break;
        }
-       up_read(&tomoyo_domain_keeper_list_lock);
        return done;
 }
 
@@ -555,6 +563,8 @@ bool tomoyo_read_domain_keeper_policy(struct tomoyo_io_buffer *head)
  *
  * Returns true if executing @program supresses domain transition,
  * false otherwise.
+ *
+ * Caller holds tomoyo_read_lock().
  */
 static bool tomoyo_is_domain_keeper(const struct tomoyo_path_info *domainname,
                                    const struct tomoyo_path_info *program,
@@ -563,8 +573,7 @@ static bool tomoyo_is_domain_keeper(const struct tomoyo_path_info *domainname,
        struct tomoyo_domain_keeper_entry *ptr;
        bool flag = false;
 
-       down_read(&tomoyo_domain_keeper_list_lock);
-       list_for_each_entry(ptr, &tomoyo_domain_keeper_list, list) {
+       list_for_each_entry_rcu(ptr, &tomoyo_domain_keeper_list, list) {
                if (ptr->is_deleted)
                        continue;
                if (!ptr->is_last_name) {
@@ -582,7 +591,6 @@ static bool tomoyo_is_domain_keeper(const struct tomoyo_path_info *domainname,
                }
                flag = true;
        }
-       up_read(&tomoyo_domain_keeper_list_lock);
        return flag;
 }
 
@@ -617,7 +625,6 @@ static bool tomoyo_is_domain_keeper(const struct tomoyo_path_info *domainname,
  * execve() succeeds is calculated using /bin/cat rather than /bin/busybox .
  */
 static LIST_HEAD(tomoyo_alias_list);
-static DECLARE_RWSEM(tomoyo_alias_list_lock);
 
 /**
  * tomoyo_update_alias_entry - Update "struct tomoyo_alias_entry" list.
@@ -627,6 +634,8 @@ static DECLARE_RWSEM(tomoyo_alias_list_lock);
  * @is_delete:     True if it is a delete request.
  *
  * Returns 0 on success, negative value otherwise.
+ *
+ * Caller holds tomoyo_read_lock().
  */
 static int tomoyo_update_alias_entry(const char *original_name,
                                     const char *aliased_name,
@@ -645,8 +654,9 @@ static int tomoyo_update_alias_entry(const char *original_name,
        saved_aliased_name = tomoyo_save_name(aliased_name);
        if (!saved_original_name || !saved_aliased_name)
                return -ENOMEM;
-       down_write(&tomoyo_alias_list_lock);
-       list_for_each_entry(ptr, &tomoyo_alias_list, list) {
+       new_entry = kmalloc(sizeof(*new_entry), GFP_KERNEL);
+       mutex_lock(&tomoyo_policy_lock);
+       list_for_each_entry_rcu(ptr, &tomoyo_alias_list, list) {
                if (ptr->original_name != saved_original_name ||
                    ptr->aliased_name != saved_aliased_name)
                        continue;
@@ -658,15 +668,16 @@ static int tomoyo_update_alias_entry(const char *original_name,
                error = -ENOENT;
                goto out;
        }
-       new_entry = tomoyo_alloc_element(sizeof(*new_entry));
-       if (!new_entry)
+       if (!tomoyo_memory_ok(new_entry))
                goto out;
        new_entry->original_name = saved_original_name;
        new_entry->aliased_name = saved_aliased_name;
-       list_add_tail(&new_entry->list, &tomoyo_alias_list);
+       list_add_tail_rcu(&new_entry->list, &tomoyo_alias_list);
+       new_entry = NULL;
        error = 0;
  out:
-       up_write(&tomoyo_alias_list_lock);
+       mutex_unlock(&tomoyo_policy_lock);
+       kfree(new_entry);
        return error;
 }
 
@@ -676,13 +687,14 @@ static int tomoyo_update_alias_entry(const char *original_name,
  * @head: Pointer to "struct tomoyo_io_buffer".
  *
  * Returns true on success, false otherwise.
+ *
+ * Caller holds tomoyo_read_lock().
  */
 bool tomoyo_read_alias_policy(struct tomoyo_io_buffer *head)
 {
        struct list_head *pos;
        bool done = true;
 
-       down_read(&tomoyo_alias_list_lock);
        list_for_each_cookie(pos, head->read_var2, &tomoyo_alias_list) {
                struct tomoyo_alias_entry *ptr;
 
@@ -695,7 +707,6 @@ bool tomoyo_read_alias_policy(struct tomoyo_io_buffer *head)
                if (!done)
                        break;
        }
-       up_read(&tomoyo_alias_list_lock);
        return done;
 }
 
@@ -706,6 +717,8 @@ bool tomoyo_read_alias_policy(struct tomoyo_io_buffer *head)
  * @is_delete: True if it is a delete request.
  *
  * Returns 0 on success, negative value otherwise.
+ *
+ * Caller holds tomoyo_read_lock().
  */
 int tomoyo_write_alias_policy(char *data, const bool is_delete)
 {
@@ -724,15 +737,17 @@ int tomoyo_write_alias_policy(char *data, const bool is_delete)
  * @profile:    Profile number to assign if the domain was newly created.
  *
  * Returns pointer to "struct tomoyo_domain_info" on success, NULL otherwise.
+ *
+ * Caller holds tomoyo_read_lock().
  */
 struct tomoyo_domain_info *tomoyo_find_or_assign_new_domain(const char *
                                                            domainname,
                                                            const u8 profile)
 {
-       struct tomoyo_domain_info *domain = NULL;
+       struct tomoyo_domain_info *domain;
        const struct tomoyo_path_info *saved_domainname;
 
-       down_write(&tomoyo_domain_list_lock);
+       mutex_lock(&tomoyo_policy_lock);
        domain = tomoyo_find_domain(domainname);
        if (domain)
                goto out;
@@ -741,45 +756,19 @@ struct tomoyo_domain_info *tomoyo_find_or_assign_new_domain(const char *
        saved_domainname = tomoyo_save_name(domainname);
        if (!saved_domainname)
                goto out;
-       /* Can I reuse memory of deleted domain? */
-       list_for_each_entry(domain, &tomoyo_domain_list, list) {
-               struct task_struct *p;
-               struct tomoyo_acl_info *ptr;
-               bool flag;
-               if (!domain->is_deleted ||
-                   domain->domainname != saved_domainname)
-                       continue;
-               flag = false;
-               read_lock(&tasklist_lock);
-               for_each_process(p) {
-                       if (tomoyo_real_domain(p) != domain)
-                               continue;
-                       flag = true;
-                       break;
-               }
-               read_unlock(&tasklist_lock);
-               if (flag)
-                       continue;
-               list_for_each_entry(ptr, &domain->acl_info_list, list) {
-                       ptr->type |= TOMOYO_ACL_DELETED;
-               }
-               tomoyo_set_domain_flag(domain, true, domain->flags);
-               domain->profile = profile;
-               domain->quota_warned = false;
-               mb(); /* Avoid out-of-order execution. */
-               domain->is_deleted = false;
-               goto out;
-       }
-       /* No memory reusable. Create using new memory. */
-       domain = tomoyo_alloc_element(sizeof(*domain));
-       if (domain) {
+       domain = kmalloc(sizeof(*domain), GFP_KERNEL);
+       if (tomoyo_memory_ok(domain)) {
                INIT_LIST_HEAD(&domain->acl_info_list);
                domain->domainname = saved_domainname;
                domain->profile = profile;
-               list_add_tail(&domain->list, &tomoyo_domain_list);
+               list_add_tail_rcu(&domain->list, &tomoyo_domain_list);
+       } else {
+               kfree(domain);
+               domain = NULL;
        }
+
  out:
-       up_write(&tomoyo_domain_list_lock);
+       mutex_unlock(&tomoyo_policy_lock);
        return domain;
 }
 
@@ -789,6 +778,8 @@ struct tomoyo_domain_info *tomoyo_find_or_assign_new_domain(const char *
  * @bprm: Pointer to "struct linux_binprm".
  *
  * Returns 0 on success, negative value otherwise.
+ *
+ * Caller holds tomoyo_read_lock().
  */
 int tomoyo_find_next_domain(struct linux_binprm *bprm)
 {
@@ -796,7 +787,7 @@ int tomoyo_find_next_domain(struct linux_binprm *bprm)
         * This function assumes that the size of buffer returned by
         * tomoyo_realpath() = TOMOYO_MAX_PATHNAME_LEN.
         */
-       struct tomoyo_page_buffer *tmp = tomoyo_alloc(sizeof(*tmp));
+       struct tomoyo_page_buffer *tmp = kzalloc(sizeof(*tmp), GFP_KERNEL);
        struct tomoyo_domain_info *old_domain = tomoyo_domain();
        struct tomoyo_domain_info *domain = NULL;
        const char *old_domain_name = old_domain->domainname->name;
@@ -849,8 +840,7 @@ int tomoyo_find_next_domain(struct linux_binprm *bprm)
        if (tomoyo_pathcmp(&r, &s)) {
                struct tomoyo_alias_entry *ptr;
                /* Is this program allowed to be called via symbolic links? */
-               down_read(&tomoyo_alias_list_lock);
-               list_for_each_entry(ptr, &tomoyo_alias_list, list) {
+               list_for_each_entry_rcu(ptr, &tomoyo_alias_list, list) {
                        if (ptr->is_deleted ||
                            tomoyo_pathcmp(&r, ptr->original_name) ||
                            tomoyo_pathcmp(&s, ptr->aliased_name))
@@ -861,7 +851,6 @@ int tomoyo_find_next_domain(struct linux_binprm *bprm)
                        tomoyo_fill_path_info(&r);
                        break;
                }
-               up_read(&tomoyo_alias_list_lock);
        }
 
        /* Check execute permission. */
@@ -892,9 +881,7 @@ int tomoyo_find_next_domain(struct linux_binprm *bprm)
        }
        if (domain || strlen(new_domain_name) >= TOMOYO_MAX_PATHNAME_LEN)
                goto done;
-       down_read(&tomoyo_domain_list_lock);
        domain = tomoyo_find_domain(new_domain_name);
-       up_read(&tomoyo_domain_list_lock);
        if (domain)
                goto done;
        if (is_enforce)
@@ -915,8 +902,8 @@ int tomoyo_find_next_domain(struct linux_binprm *bprm)
        if (!domain)
                domain = old_domain;
        bprm->cred->security = domain;
-       tomoyo_free(real_program_name);
-       tomoyo_free(symlink_program_name);
-       tomoyo_free(tmp);
+       kfree(real_program_name);
+       kfree(symlink_program_name);
+       kfree(tmp);
        return retval;
 }