TOMOYO: Add policy namespace support.

Mauras Olivier reported that it is difficult to use TOMOYO in LXC environments,
for TOMOYO cannot distinguish between environments outside the container and
environments inside the container since LXC environments are created using
pivot_root(). To address this problem, this patch introduces policy namespace.

Each policy namespace has its own set of domain policy, exception policy and
profiles, which are all independent of other namespaces. This independency
allows users to develop policy without worrying interference among namespaces.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>

1 files changed, 278 insertions, 105 deletions

diff --git a/security/tomoyo/common.c b/security/tomoyo/common.c
index 507ebf01e43b..50481d2cf970 100644
--- a/security/tomoyo/common.c
+++ b/security/tomoyo/common.c
@@ -11,12 +11,6 @@
 #include <linux/security.h>
 #include "common.h"
 
-/* Profile version. Currently only 20090903 is defined. */
-static unsigned int tomoyo_profile_version;
-
-/* Profile table. Memory is allocated as needed. */
-static struct tomoyo_profile *tomoyo_profile_ptr[TOMOYO_MAX_PROFILES];
-
 /* String table for operation mode. */
 const char * const tomoyo_mode[TOMOYO_CONFIG_MAX_MODE] = {
 	[TOMOYO_CONFIG_DISABLED]   = "disabled",
@@ -216,6 +210,50 @@ static void tomoyo_set_slash(struct tomoyo_io_buffer *head)
 	tomoyo_set_string(head, "/");
 }
 
+/* List of namespaces. */
+LIST_HEAD(tomoyo_namespace_list);
+/* True if namespace other than tomoyo_kernel_namespace is defined. */
+static bool tomoyo_namespace_enabled;
+
+/**
+ * tomoyo_init_policy_namespace - Initialize namespace.
+ *
+ * @ns: Pointer to "struct tomoyo_policy_namespace".
+ *
+ * Returns nothing.
+ */
+void tomoyo_init_policy_namespace(struct tomoyo_policy_namespace *ns)
+{
+	unsigned int idx;
+	for (idx = 0; idx < TOMOYO_MAX_ACL_GROUPS; idx++)
+		INIT_LIST_HEAD(&ns->acl_group[idx]);
+	for (idx = 0; idx < TOMOYO_MAX_GROUP; idx++)
+		INIT_LIST_HEAD(&ns->group_list[idx]);
+	for (idx = 0; idx < TOMOYO_MAX_POLICY; idx++)
+		INIT_LIST_HEAD(&ns->policy_list[idx]);
+	ns->profile_version = 20100903;
+	tomoyo_namespace_enabled = !list_empty(&tomoyo_namespace_list);
+	list_add_tail_rcu(&ns->namespace_list, &tomoyo_namespace_list);
+}
+
+/**
+ * tomoyo_print_namespace - Print namespace header.
+ *
+ * @head: Pointer to "struct tomoyo_io_buffer".
+ *
+ * Returns nothing.
+ */
+static void tomoyo_print_namespace(struct tomoyo_io_buffer *head)
+{
+	if (!tomoyo_namespace_enabled)
+		return;
+	tomoyo_set_string(head,
+			  container_of(head->r.ns,
+				       struct tomoyo_policy_namespace,
+				       namespace_list)->name);
+	tomoyo_set_space(head);
+}
+
 /**
  * tomoyo_print_name_union - Print a tomoyo_name_union.
  *
@@ -283,23 +321,25 @@ static void tomoyo_print_number_union(struct tomoyo_io_buffer *head,
 /**
  * tomoyo_assign_profile - Create a new profile.
  *
+ * @ns:      Pointer to "struct tomoyo_policy_namespace".
  * @profile: Profile number to create.
  *
  * Returns pointer to "struct tomoyo_profile" on success, NULL otherwise.
  */
-static struct tomoyo_profile *tomoyo_assign_profile(const unsigned int profile)
+static struct tomoyo_profile *tomoyo_assign_profile
+(struct tomoyo_policy_namespace *ns, const unsigned int profile)
 {
 	struct tomoyo_profile *ptr;
 	struct tomoyo_profile *entry;
 	if (profile >= TOMOYO_MAX_PROFILES)
 		return NULL;
-	ptr = tomoyo_profile_ptr[profile];
+	ptr = ns->profile_ptr[profile];
 	if (ptr)
 		return ptr;
 	entry = kzalloc(sizeof(*entry), GFP_NOFS);
 	if (mutex_lock_interruptible(&tomoyo_policy_lock))
 		goto out;
-	ptr = tomoyo_profile_ptr[profile];
+	ptr = ns->profile_ptr[profile];
 	if (!ptr && tomoyo_memory_ok(entry)) {
 		ptr = entry;
 		ptr->default_config = TOMOYO_CONFIG_DISABLED |
@@ -310,7 +350,7 @@ static struct tomoyo_profile *tomoyo_assign_profile(const unsigned int profile)
 		ptr->pref[TOMOYO_PREF_MAX_AUDIT_LOG] = 1024;
 		ptr->pref[TOMOYO_PREF_MAX_LEARNING_ENTRY] = 2048;
 		mb(); /* Avoid out-of-order execution. */
-		tomoyo_profile_ptr[profile] = ptr;
+		ns->profile_ptr[profile] = ptr;
 		entry = NULL;
 	}
 	mutex_unlock(&tomoyo_policy_lock);
@@ -322,14 +362,16 @@ static struct tomoyo_profile *tomoyo_assign_profile(const unsigned int profile)
 /**
  * tomoyo_profile - Find a profile.
  *
+ * @ns:      Pointer to "struct tomoyo_policy_namespace".
  * @profile: Profile number to find.
  *
  * Returns pointer to "struct tomoyo_profile".
  */
-struct tomoyo_profile *tomoyo_profile(const u8 profile)
+struct tomoyo_profile *tomoyo_profile(const struct tomoyo_policy_namespace *ns,
+				      const u8 profile)
 {
 	static struct tomoyo_profile tomoyo_null_profile;
-	struct tomoyo_profile *ptr = tomoyo_profile_ptr[profile];
+	struct tomoyo_profile *ptr = ns->profile_ptr[profile];
 	if (!ptr)
 		ptr = &tomoyo_null_profile;
 	return ptr;
@@ -454,13 +496,14 @@ static int tomoyo_write_profile(struct tomoyo_io_buffer *head)
 	unsigned int i;
 	char *cp;
 	struct tomoyo_profile *profile;
-	if (sscanf(data, "PROFILE_VERSION=%u", &tomoyo_profile_version) == 1)
+	if (sscanf(data, "PROFILE_VERSION=%u", &head->w.ns->profile_version)
+	    == 1)
 		return 0;
 	i = simple_strtoul(data, &cp, 10);
 	if (*cp != '-')
 		return -EINVAL;
 	data = cp + 1;
-	profile = tomoyo_assign_profile(i);
+	profile = tomoyo_assign_profile(head->w.ns, i);
 	if (!profile)
 		return -EINVAL;
 	cp = strchr(data, '=');
@@ -518,19 +561,25 @@ static void tomoyo_print_config(struct tomoyo_io_buffer *head, const u8 config)
 static void tomoyo_read_profile(struct tomoyo_io_buffer *head)
 {
 	u8 index;
+	struct tomoyo_policy_namespace *ns =
+		container_of(head->r.ns, typeof(*ns), namespace_list);
 	const struct tomoyo_profile *profile;
+	if (head->r.eof)
+		return;
  next:
 	index = head->r.index;
-	profile = tomoyo_profile_ptr[index];
+	profile = ns->profile_ptr[index];
 	switch (head->r.step) {
 	case 0:
-		tomoyo_io_printf(head, "PROFILE_VERSION=%u\n", 20090903);
+		tomoyo_print_namespace(head);
+		tomoyo_io_printf(head, "PROFILE_VERSION=%u\n",
+				 ns->profile_version);
 		head->r.step++;
 		break;
 	case 1:
 		for ( ; head->r.index < TOMOYO_MAX_PROFILES;
 		      head->r.index++)
-			if (tomoyo_profile_ptr[head->r.index])
+			if (ns->profile_ptr[head->r.index])
 				break;
 		if (head->r.index == TOMOYO_MAX_PROFILES)
 			return;
@@ -541,6 +590,7 @@ static void tomoyo_read_profile(struct tomoyo_io_buffer *head)
 			u8 i;
 			const struct tomoyo_path_info *comment =
 				profile->comment;
+			tomoyo_print_namespace(head);
 			tomoyo_io_printf(head, "%u-COMMENT=", index);
 			tomoyo_set_string(head, comment ? comment->name : "");
 			tomoyo_set_lf(head);
@@ -555,6 +605,7 @@ static void tomoyo_read_profile(struct tomoyo_io_buffer *head)
 		break;
 	case 3:
 		{
+			tomoyo_print_namespace(head);
 			tomoyo_io_printf(head, "%u-%s", index, "CONFIG");
 			tomoyo_print_config(head, profile->default_config);
 			head->r.bit = 0;
@@ -568,6 +619,7 @@ static void tomoyo_read_profile(struct tomoyo_io_buffer *head)
 			const u8 config = profile->config[i];
 			if (config == TOMOYO_CONFIG_USE_DEFAULT)
 				continue;
+			tomoyo_print_namespace(head);
 			tomoyo_io_printf(head, "%u-%s%s", index, "CONFIG::",
 					 tomoyo_mac_keywords[i]);
 			tomoyo_print_config(head, config);
@@ -607,8 +659,10 @@ static int tomoyo_update_manager_entry(const char *manager,
 {
 	struct tomoyo_manager e = { };
 	struct tomoyo_acl_param param = {
+		/* .ns = &tomoyo_kernel_namespace, */
 		.is_delete = is_delete,
-		.list = &tomoyo_policy_list[TOMOYO_ID_MANAGER],
+		.list = &tomoyo_kernel_namespace.
+		policy_list[TOMOYO_ID_MANAGER],
 	};
 	int error = is_delete ? -ENOENT : -ENOMEM;
 	if (tomoyo_domain_def(manager)) {
@@ -640,13 +694,12 @@ static int tomoyo_update_manager_entry(const char *manager,
 static int tomoyo_write_manager(struct tomoyo_io_buffer *head)
 {
 	char *data = head->write_buf;
-	bool is_delete = tomoyo_str_starts(&data, "delete ");
 
 	if (!strcmp(data, "manage_by_non_root")) {
-		tomoyo_manage_by_non_root = !is_delete;
+		tomoyo_manage_by_non_root = !head->w.is_delete;
 		return 0;
 	}
-	return tomoyo_update_manager_entry(data, is_delete);
+	return tomoyo_update_manager_entry(data, head->w.is_delete);
 }
 
 /**
@@ -660,8 +713,8 @@ static void tomoyo_read_manager(struct tomoyo_io_buffer *head)
 {
 	if (head->r.eof)
 		return;
-	list_for_each_cookie(head->r.acl,
-			     &tomoyo_policy_list[TOMOYO_ID_MANAGER]) {
+	list_for_each_cookie(head->r.acl, &tomoyo_kernel_namespace.
+			     policy_list[TOMOYO_ID_MANAGER]) {
 		struct tomoyo_manager *ptr =
 			list_entry(head->r.acl, typeof(*ptr), head.list);
 		if (ptr->head.is_deleted)
@@ -694,8 +747,8 @@ static bool tomoyo_manager(void)
 		return true;
 	if (!tomoyo_manage_by_non_root && (task->cred->uid || task->cred->euid))
 		return false;
-	list_for_each_entry_rcu(ptr, &tomoyo_policy_list[TOMOYO_ID_MANAGER],
-				head.list) {
+	list_for_each_entry_rcu(ptr, &tomoyo_kernel_namespace.
+				policy_list[TOMOYO_ID_MANAGER], head.list) {
 		if (!ptr->head.is_deleted && ptr->is_domain
 		    && !tomoyo_pathcmp(domainname, ptr->manager)) {
 			found = true;
@@ -707,8 +760,8 @@ static bool tomoyo_manager(void)
 	exe = tomoyo_get_exe();
 	if (!exe)
 		return false;
-	list_for_each_entry_rcu(ptr, &tomoyo_policy_list[TOMOYO_ID_MANAGER],
-				head.list) {
+	list_for_each_entry_rcu(ptr, &tomoyo_kernel_namespace.
+				policy_list[TOMOYO_ID_MANAGER], head.list) {
 		if (!ptr->head.is_deleted && !ptr->is_domain
 		    && !strcmp(exe, ptr->manager->name)) {
 			found = true;
@@ -729,7 +782,7 @@ static bool tomoyo_manager(void)
 }
 
 /**
- * tomoyo_select_one - Parse select command.
+ * tomoyo_select_domain - Parse select command.
  *
  * @head: Pointer to "struct tomoyo_io_buffer".
  * @data: String to parse.
@@ -738,16 +791,15 @@ static bool tomoyo_manager(void)
  *
  * Caller holds tomoyo_read_lock().
  */
-static bool tomoyo_select_one(struct tomoyo_io_buffer *head, const char *data)
+static bool tomoyo_select_domain(struct tomoyo_io_buffer *head,
+				 const char *data)
 {
 	unsigned int pid;
 	struct tomoyo_domain_info *domain = NULL;
 	bool global_pid = false;
-
-	if (!strcmp(data, "allow_execute")) {
-		head->r.print_execute_only = true;
-		return true;
-	}
+	if (strncmp(data, "select ", 7))
+		return false;
+	data += 7;
 	if (sscanf(data, "pid=%u", &pid) == 1 ||
 	    (global_pid = true, sscanf(data, "global-pid=%u", &pid) == 1)) {
 		struct task_struct *p;
@@ -818,6 +870,7 @@ static int tomoyo_delete_domain(char *domainname)
 /**
  * tomoyo_write_domain2 - Write domain policy.
  *
+ * @ns:        Pointer to "struct tomoyo_policy_namespace".
  * @list:      Pointer to "struct list_head".
  * @data:      Policy to be interpreted.
  * @is_delete: True if it is a delete request.
@@ -826,10 +879,12 @@ static int tomoyo_delete_domain(char *domainname)
  *
  * Caller holds tomoyo_read_lock().
  */
-static int tomoyo_write_domain2(struct list_head *list, char *data,
+static int tomoyo_write_domain2(struct tomoyo_policy_namespace *ns,
+				struct list_head *list, char *data,
 				const bool is_delete)
 {
 	struct tomoyo_acl_param param = {
+		.ns = ns,
 		.list = list,
 		.data = data,
 		.is_delete = is_delete,
@@ -862,37 +917,28 @@ static int tomoyo_write_domain2(struct list_head *list, char *data,
 static int tomoyo_write_domain(struct tomoyo_io_buffer *head)
 {
 	char *data = head->write_buf;
+	struct tomoyo_policy_namespace *ns;
 	struct tomoyo_domain_info *domain = head->w.domain;
-	bool is_delete = false;
-	bool is_select = false;
+	const bool is_delete = head->w.is_delete;
+	bool is_select = !is_delete && tomoyo_str_starts(&data, "select ");
 	unsigned int profile;
-
-	if (tomoyo_str_starts(&data, "delete "))
-		is_delete = true;
-	else if (tomoyo_str_starts(&data, "select "))
-		is_select = true;
-	if (is_select && tomoyo_select_one(head, data))
-		return 0;
-	/* Don't allow updating policies by non manager programs. */
-	if (!tomoyo_manager())
-		return -EPERM;
-	if (tomoyo_domain_def(data)) {
+	if (*data == '<') {
 		domain = NULL;
 		if (is_delete)
 			tomoyo_delete_domain(data);
 		else if (is_select)
 			domain = tomoyo_find_domain(data);
 		else
-			domain = tomoyo_assign_domain(data, 0);
+			domain = tomoyo_assign_domain(data, false);
 		head->w.domain = domain;
 		return 0;
 	}
 	if (!domain)
 		return -EINVAL;
-
+	ns = domain->ns;
 	if (sscanf(data, "use_profile %u", &profile) == 1
 	    && profile < TOMOYO_MAX_PROFILES) {
-		if (tomoyo_profile_ptr[profile] || !tomoyo_policy_loaded)
+		if (!tomoyo_policy_loaded || ns->profile_ptr[profile])
 			domain->profile = (u8) profile;
 		return 0;
 	}
@@ -910,7 +956,8 @@ static int tomoyo_write_domain(struct tomoyo_io_buffer *head)
 		domain->transition_failed = !is_delete;
 		return 0;
 	}
-	return tomoyo_write_domain2(&domain->acl_info_list, data, is_delete);
+	return tomoyo_write_domain2(ns, &domain->acl_info_list, data,
+				    is_delete);
 }
 
 /**
@@ -924,9 +971,11 @@ static int tomoyo_write_domain(struct tomoyo_io_buffer *head)
 static void tomoyo_set_group(struct tomoyo_io_buffer *head,
 			     const char *category)
 {
-	if (head->type == TOMOYO_EXCEPTIONPOLICY)
+	if (head->type == TOMOYO_EXCEPTIONPOLICY) {
+		tomoyo_print_namespace(head);
 		tomoyo_io_printf(head, "acl_group %u ",
 				 head->r.acl_group_index);
+	}
 	tomoyo_set_string(head, category);
 }
 
@@ -956,7 +1005,7 @@ static bool tomoyo_print_entry(struct tomoyo_io_buffer *head,
 		for (bit = 0; bit < TOMOYO_MAX_PATH_OPERATION; bit++) {
 			if (!(perm & (1 << bit)))
 				continue;
-			if (head->r.print_execute_only &&
+			if (head->r.print_transition_related_only &&
 			    bit != TOMOYO_TYPE_EXECUTE)
 				continue;
 			if (first) {
@@ -970,7 +1019,7 @@ static bool tomoyo_print_entry(struct tomoyo_io_buffer *head,
 		if (first)
 			return true;
 		tomoyo_print_name_union(head, &ptr->name);
-	} else if (head->r.print_execute_only) {
+	} else if (head->r.print_transition_related_only) {
 		return true;
 	} else if (acl_type == TOMOYO_TYPE_PATH2_ACL) {
 		struct tomoyo_path2_acl *ptr =
@@ -1147,8 +1196,8 @@ static int tomoyo_write_domain_profile(struct tomoyo_io_buffer *head)
 	domain = tomoyo_find_domain(cp + 1);
 	if (strict_strtoul(data, 10, &profile))
 		return -EINVAL;
-	if (domain && profile < TOMOYO_MAX_PROFILES
-	    && (tomoyo_profile_ptr[profile] || !tomoyo_policy_loaded))
+	if (domain && (!tomoyo_policy_loaded ||
+		       head->w.ns->profile_ptr[(u8) profile]))
 		domain->profile = (u8) profile;
 	return 0;
 }
@@ -1246,10 +1295,12 @@ static void tomoyo_read_pid(struct tomoyo_io_buffer *head)
 }
 
 static const char *tomoyo_transition_type[TOMOYO_MAX_TRANSITION_TYPE] = {
-	[TOMOYO_TRANSITION_CONTROL_NO_INITIALIZE] = "no_initialize_domain",
-	[TOMOYO_TRANSITION_CONTROL_INITIALIZE]    = "initialize_domain",
-	[TOMOYO_TRANSITION_CONTROL_NO_KEEP]       = "no_keep_domain",
-	[TOMOYO_TRANSITION_CONTROL_KEEP]          = "keep_domain",
+	[TOMOYO_TRANSITION_CONTROL_NO_RESET]      = "no_reset_domain ",
+	[TOMOYO_TRANSITION_CONTROL_RESET]         = "reset_domain ",
+	[TOMOYO_TRANSITION_CONTROL_NO_INITIALIZE] = "no_initialize_domain ",
+	[TOMOYO_TRANSITION_CONTROL_INITIALIZE]    = "initialize_domain ",
+	[TOMOYO_TRANSITION_CONTROL_NO_KEEP]       = "no_keep_domain ",
+	[TOMOYO_TRANSITION_CONTROL_KEEP]          = "keep_domain ",
 };
 
 static const char *tomoyo_group_name[TOMOYO_MAX_GROUP] = {
@@ -1268,19 +1319,13 @@ static const char *tomoyo_group_name[TOMOYO_MAX_GROUP] = {
  */
 static int tomoyo_write_exception(struct tomoyo_io_buffer *head)
 {
+	const bool is_delete = head->w.is_delete;
 	struct tomoyo_acl_param param = {
+		.ns = head->w.ns,
+		.is_delete = is_delete,
 		.data = head->write_buf,
 	};
 	u8 i;
-	param.is_delete = tomoyo_str_starts(&param.data, "delete ");
-	if (!param.is_delete && tomoyo_str_starts(&param.data, "select ") &&
-	    !strcmp(param.data, "execute_only")) {
-		head->r.print_execute_only = true;
-		return 0;
-	}
-	/* Don't allow updating policies by non manager programs. */
-	if (!tomoyo_manager())
-		return -EPERM;
 	if (tomoyo_str_starts(&param.data, "aggregator "))
 		return tomoyo_write_aggregator(&param);
 	for (i = 0; i < TOMOYO_MAX_TRANSITION_TYPE; i++)
@@ -1294,8 +1339,9 @@ static int tomoyo_write_exception(struct tomoyo_io_buffer *head)
 		char *data;
 		group = simple_strtoul(param.data, &data, 10);
 		if (group < TOMOYO_MAX_ACL_GROUPS && *data++ == ' ')
-			return tomoyo_write_domain2(&tomoyo_acl_group[group],
-						    data, param.is_delete);
+			return tomoyo_write_domain2
+				(head->w.ns, &head->w.ns->acl_group[group],
+				 data, is_delete);
 	}
 	return -EINVAL;
 }
@@ -1312,7 +1358,10 @@ static int tomoyo_write_exception(struct tomoyo_io_buffer *head)
  */
 static bool tomoyo_read_group(struct tomoyo_io_buffer *head, const int idx)
 {
-	list_for_each_cookie(head->r.group, &tomoyo_group_list[idx]) {
+	struct tomoyo_policy_namespace *ns =
+		container_of(head->r.ns, typeof(*ns), namespace_list);
+	struct list_head *list = &ns->group_list[idx];
+	list_for_each_cookie(head->r.group, list) {
 		struct tomoyo_group *group =
 			list_entry(head->r.group, typeof(*group), head.list);
 		list_for_each_cookie(head->r.acl, &group->member_list) {
@@ -1322,6 +1371,7 @@ static bool tomoyo_read_group(struct tomoyo_io_buffer *head, const int idx)
 				continue;
 			if (!tomoyo_flush(head))
 				return false;
+			tomoyo_print_namespace(head);
 			tomoyo_set_string(head, tomoyo_group_name[idx]);
 			tomoyo_set_string(head, group->group_name->name);
 			if (idx == TOMOYO_PATH_GROUP) {
@@ -1355,7 +1405,10 @@ static bool tomoyo_read_group(struct tomoyo_io_buffer *head, const int idx)
  */
 static bool tomoyo_read_policy(struct tomoyo_io_buffer *head, const int idx)
 {
-	list_for_each_cookie(head->r.acl, &tomoyo_policy_list[idx]) {
+	struct tomoyo_policy_namespace *ns =
+		container_of(head->r.ns, typeof(*ns), namespace_list);
+	struct list_head *list = &ns->policy_list[idx];
+	list_for_each_cookie(head->r.acl, list) {
 		struct tomoyo_acl_head *acl =
 			container_of(head->r.acl, typeof(*acl), list);
 		if (acl->is_deleted)
@@ -1367,6 +1420,7 @@ static bool tomoyo_read_policy(struct tomoyo_io_buffer *head, const int idx)
 			{
 				struct tomoyo_transition_control *ptr =
 					container_of(acl, typeof(*ptr), head);
+				tomoyo_print_namespace(head);
 				tomoyo_set_string(head, tomoyo_transition_type
 						  [ptr->type]);
 				tomoyo_set_string(head, ptr->program ?
@@ -1381,6 +1435,7 @@ static bool tomoyo_read_policy(struct tomoyo_io_buffer *head, const int idx)
 			{
 				struct tomoyo_aggregator *ptr =
 					container_of(acl, typeof(*ptr), head);
+				tomoyo_print_namespace(head);
 				tomoyo_set_string(head, "aggregator ");
 				tomoyo_set_string(head,
 						  ptr->original_name->name);
@@ -1407,6 +1462,8 @@ static bool tomoyo_read_policy(struct tomoyo_io_buffer *head, const int idx)
  */
 static void tomoyo_read_exception(struct tomoyo_io_buffer *head)
 {
+	struct tomoyo_policy_namespace *ns =
+		container_of(head->r.ns, typeof(*ns), namespace_list);
 	if (head->r.eof)
 		return;
 	while (head->r.step < TOMOYO_MAX_POLICY &&
@@ -1423,7 +1480,7 @@ static void tomoyo_read_exception(struct tomoyo_io_buffer *head)
 	       + TOMOYO_MAX_ACL_GROUPS) {
 		head->r.acl_group_index = head->r.step - TOMOYO_MAX_POLICY
 			- TOMOYO_MAX_GROUP;
-		if (!tomoyo_read_domain2(head, &tomoyo_acl_group
+		if (!tomoyo_read_domain2(head, &ns->acl_group
 					 [head->r.acl_group_index]))
 			return;
 		head->r.step++;
@@ -1484,7 +1541,8 @@ static void tomoyo_add_entry(struct tomoyo_domain_info *domain, char *header)
 		return;
 	snprintf(buffer, len - 1, "%s", cp);
 	tomoyo_normalize_line(buffer);
-	tomoyo_write_domain2(&domain->acl_info_list, buffer, false);
+	tomoyo_write_domain2(domain->ns, &domain->acl_info_list, buffer,
+			     false);
 	kfree(buffer);
 }
 
@@ -1896,6 +1954,45 @@ int tomoyo_poll_control(struct file *file, poll_table *wait)
 }
 
 /**
+ * tomoyo_set_namespace_cursor - Set namespace to read.
+ *
+ * @head: Pointer to "struct tomoyo_io_buffer".
+ *
+ * Returns nothing.
+ */
+static inline void tomoyo_set_namespace_cursor(struct tomoyo_io_buffer *head)
+{
+	struct list_head *ns;
+	if (head->type != TOMOYO_EXCEPTIONPOLICY &&
+	    head->type != TOMOYO_PROFILE)
+		return;
+	/*
+	 * If this is the first read, or reading previous namespace finished
+	 * and has more namespaces to read, update the namespace cursor.
+	 */
+	ns = head->r.ns;
+	if (!ns || (head->r.eof && ns->next != &tomoyo_namespace_list)) {
+		/* Clearing is OK because tomoyo_flush() returned true. */
+		memset(&head->r, 0, sizeof(head->r));
+		head->r.ns = ns ? ns->next : tomoyo_namespace_list.next;
+	}
+}
+
+/**
+ * tomoyo_has_more_namespace - Check for unread namespaces.
+ *
+ * @head: Pointer to "struct tomoyo_io_buffer".
+ *
+ * Returns true if we have more entries to print, false otherwise.
+ */
+static inline bool tomoyo_has_more_namespace(struct tomoyo_io_buffer *head)
+{
+	return (head->type == TOMOYO_EXCEPTIONPOLICY ||
+		head->type == TOMOYO_PROFILE) && head->r.eof &&
+		head->r.ns->next != &tomoyo_namespace_list;
+}
+
+/**
  * tomoyo_read_control - read() for /sys/kernel/security/tomoyo/ interface.
  *
  * @head:       Pointer to "struct tomoyo_io_buffer".
@@ -1919,14 +2016,54 @@ int tomoyo_read_control(struct tomoyo_io_buffer *head, char __user *buffer,
 	head->read_user_buf_avail = buffer_len;
 	if (tomoyo_flush(head))
 		/* Call the policy handler. */
-		head->read(head);
-	tomoyo_flush(head);
+		do {
+			tomoyo_set_namespace_cursor(head);
+			head->read(head);
+		} while (tomoyo_flush(head) &&
+			 tomoyo_has_more_namespace(head));
 	len = head->read_user_buf - buffer;
 	mutex_unlock(&head->io_sem);
 	return len;
 }
 
 /**
+ * tomoyo_parse_policy - Parse a policy line.
+ *
+ * @head: Poiter to "struct tomoyo_io_buffer".
+ * @line: Line to parse.
+ *
+ * Returns 0 on success, negative value otherwise.
+ *
+ * Caller holds tomoyo_read_lock().
+ */
+static int tomoyo_parse_policy(struct tomoyo_io_buffer *head, char *line)
+{
+	/* Delete request? */
+	head->w.is_delete = !strncmp(line, "delete ", 7);
+	if (head->w.is_delete)
+		memmove(line, line + 7, strlen(line + 7) + 1);
+	/* Selecting namespace to update. */
+	if (head->type == TOMOYO_EXCEPTIONPOLICY ||
+	    head->type == TOMOYO_PROFILE) {
+		if (*line == '<') {
+			char *cp = strchr(line, ' ');
+			if (cp) {
+				*cp++ = '\0';
+				head->w.ns = tomoyo_assign_namespace(line);
+				memmove(line, cp, strlen(cp) + 1);
+			} else
+				head->w.ns = NULL;
+		} else
+			head->w.ns = &tomoyo_kernel_namespace;
+		/* Don't allow updating if namespace is invalid. */
+		if (!head->w.ns)
+			return -ENOENT;
+	}
+	/* Do the update. */
+	return head->write(head);
+}
+
+/**
  * tomoyo_write_control - write() for /sys/kernel/security/tomoyo/ interface.
  *
  * @head:       Pointer to "struct tomoyo_io_buffer".
@@ -1941,27 +2078,31 @@ int tomoyo_write_control(struct tomoyo_io_buffer *head,
 			 const char __user *buffer, const int buffer_len)
 {
 	int error = buffer_len;
-	int avail_len = buffer_len;
+	size_t avail_len = buffer_len;
 	char *cp0 = head->write_buf;
-
 	if (!head->write)
 		return -ENOSYS;
 	if (!access_ok(VERIFY_READ, buffer, buffer_len))
 		return -EFAULT;
-	/* Don't allow updating policies by non manager programs. */
-	if (head->write != tomoyo_write_pid &&
-	    head->write != tomoyo_write_domain &&
-	    head->write != tomoyo_write_exception && !tomoyo_manager())
-		return -EPERM;
 	if (mutex_lock_interruptible(&head->io_sem))
 		return -EINTR;
 	/* Read a line and dispatch it to the policy handler. */
 	while (avail_len > 0) {
 		char c;
 		if (head->w.avail >= head->writebuf_size - 1) {
-			error = -ENOMEM;
-			break;
-		} else if (get_user(c, buffer)) {
+			const int len = head->writebuf_size * 2;
+			char *cp = kzalloc(len, GFP_NOFS);
+			if (!cp) {
+				error = -ENOMEM;
+				break;
+			}
+			memmove(cp, cp0, head->w.avail);
+			kfree(cp0);
+			head->write_buf = cp;
+			cp0 = cp;
+			head->writebuf_size = len;
+		}
+		if (get_user(c, buffer)) {
 			error = -EFAULT;
 			break;
 		}
@@ -1973,8 +2114,40 @@ int tomoyo_write_control(struct tomoyo_io_buffer *head,
 		cp0[head->w.avail - 1] = '\0';
 		head->w.avail = 0;
 		tomoyo_normalize_line(cp0);
-		head->write(head);
+		if (!strcmp(cp0, "reset")) {
+			head->w.ns = &tomoyo_kernel_namespace;
+			head->w.domain = NULL;
+			memset(&head->r, 0, sizeof(head->r));
+			continue;
+		}
+		/* Don't allow updating policies by non manager programs. */
+		switch (head->type) {
+		case TOMOYO_PROCESS_STATUS:
+			/* This does not write anything. */
+			break;
+		case TOMOYO_DOMAINPOLICY:
+			if (tomoyo_select_domain(head, cp0))
+				continue;
+			/* fall through */
+		case TOMOYO_EXCEPTIONPOLICY:
+			if (!strcmp(cp0, "select transition_only")) {
+				head->r.print_transition_related_only = true;
+				continue;
+			}
+			/* fall through */
+		default:
+			if (!tomoyo_manager()) {
+				error = -EPERM;
+				goto out;
+			}
+		}
+		switch (tomoyo_parse_policy(head, cp0)) {
+		case -EPERM:
+			error = -EPERM;
+			goto out;
+		}
 	}
+out:
 	mutex_unlock(&head->io_sem);
 	return error;
 }
@@ -2019,27 +2192,27 @@ void tomoyo_check_profile(void)
 	struct tomoyo_domain_info *domain;
 	const int idx = tomoyo_read_lock();
 	tomoyo_policy_loaded = true;
-	/* Check all profiles currently assigned to domains are defined. */
+	printk(KERN_INFO "TOMOYO: 2.4.0\n");
 	list_for_each_entry_rcu(domain, &tomoyo_domain_list, list) {
 		const u8 profile = domain->profile;
-		if (tomoyo_profile_ptr[profile])
+		const struct tomoyo_policy_namespace *ns = domain->ns;
+		if (ns->profile_version != 20100903)
+			printk(KERN_ERR
+			       "Profile version %u is not supported.\n",
+			       ns->profile_version);
+		else if (!ns->profile_ptr[profile])
+			printk(KERN_ERR
+			       "Profile %u (used by '%s') is not defined.\n",
+			       profile, domain->domainname->name);
+		else
 			continue;
-		printk(KERN_ERR "You need to define profile %u before using it.\n",
-		       profile);
-		printk(KERN_ERR "Please see http://tomoyo.sourceforge.jp/2.3/ "
+		printk(KERN_ERR
+		       "Userland tools for TOMOYO 2.4 must be installed and "
+		       "policy must be initialized.\n");
+		printk(KERN_ERR "Please see http://tomoyo.sourceforge.jp/2.4/ "
 		       "for more information.\n");
-		panic("Profile %u (used by '%s') not defined.\n",
-		      profile, domain->domainname->name);
+		panic("STOP!");
 	}
 	tomoyo_read_unlock(idx);
-	if (tomoyo_profile_version != 20090903) {
-		printk(KERN_ERR "You need to install userland programs for "
-		       "TOMOYO 2.3 and initialize policy configuration.\n");
-		printk(KERN_ERR "Please see http://tomoyo.sourceforge.jp/2.3/ "
-		       "for more information.\n");
-		panic("Profile version %u is not supported.\n",
-		      tomoyo_profile_version);
-	}
-	printk(KERN_INFO "TOMOYO: 2.3.0\n");
 	printk(KERN_INFO "Mandatory Access Control activated.\n");
 }