Message-Id: <200906020141.n521faqb003256@www262.sakura.ne.jp>
Date:	Tue, 02 Jun 2009 10:41:36 +0900
From:	Tetsuo Handa <penguin-kernel@...ove.sakura.ne.jp>
To:	linux-security-module@...r.kernel.org
Cc:	linux-kernel@...r.kernel.org
Subject: [PATCH 1/5] Move sleeping operations to outside the semaphore.

TOMOYO is using rw_semaphore for protecting list elements.
But TOMOYO is doing operations which might sleep inside down_write().
This patch makes TOMOYO's sleeping operations go outside down_write().

Signed-off-by: Kentaro Takeda <takedakn@...data.co.jp>
Signed-off-by: Tetsuo Handa <penguin-kernel@...ove.SAKURA.ne.jp>
Signed-off-by: Toshiharu Harada <haradats@...data.co.jp>
---
 security/tomoyo/common.c   |   80 ++++++---------------
 security/tomoyo/common.h   |    2 
 security/tomoyo/domain.c   |  107 ++++++++++++++--------------
 security/tomoyo/file.c     |  133 ++++++++++++++++++-----------------
 security/tomoyo/realpath.c |  169 ++++++++++++++-------------------------------
 security/tomoyo/realpath.h |    7 -
 6 files changed, 205 insertions(+), 293 deletions(-)

--- security-testing-2.6.git.orig/security/tomoyo/common.c
+++ security-testing-2.6.git/security/tomoyo/common.c
@@ -861,26 +861,27 @@ static struct tomoyo_profile *tomoyo_fin
 								int profile)
 {
 	static DEFINE_MUTEX(lock);
-	struct tomoyo_profile *ptr = NULL;
-	int i;
+	struct tomoyo_profile *new_ptr = NULL;
+	struct tomoyo_profile *ptr;
 
 	if (profile >= TOMOYO_MAX_PROFILES)
 		return NULL;
+	new_ptr = kmalloc(sizeof(*new_ptr), GFP_KERNEL);
 	/***** EXCLUSIVE SECTION START *****/
 	mutex_lock(&lock);
 	ptr = tomoyo_profile_ptr[profile];
-	if (ptr)
-		goto ok;
-	ptr = tomoyo_alloc_element(sizeof(*ptr));
-	if (!ptr)
-		goto ok;
-	for (i = 0; i < TOMOYO_MAX_CONTROL_INDEX; i++)
-		ptr->value[i] = tomoyo_control_array[i].current_value;
-	mb(); /* Avoid out-of-order execution. */
-	tomoyo_profile_ptr[profile] = ptr;
- ok:
+	if (!ptr && tomoyo_memory_ok(new_ptr)) {
+		int i;
+		ptr = new_ptr;
+		new_ptr = NULL;
+		for (i = 0; i < TOMOYO_MAX_CONTROL_INDEX; i++)
+			ptr->value[i] = tomoyo_control_array[i].current_value;
+		mb(); /* Avoid out-of-order execution. */
+		tomoyo_profile_ptr[profile] = ptr;
+	}
 	mutex_unlock(&lock);
 	/***** EXCLUSIVE SECTION END *****/
+	kfree(new_ptr);
 	return ptr;
 }
 
@@ -1033,10 +1034,10 @@ static DECLARE_RWSEM(tomoyo_policy_manag
 static int tomoyo_update_manager_entry(const char *manager,
 				       const bool is_delete)
 {
-	struct tomoyo_policy_manager_entry *new_entry;
+	struct tomoyo_policy_manager_entry *new_entry = NULL;
 	struct tomoyo_policy_manager_entry *ptr;
 	const struct tomoyo_path_info *saved_manager;
-	int error = -ENOMEM;
+	int error = is_delete ? -ENOENT : -ENOMEM;
 	bool is_domain = false;
 
 	if (tomoyo_is_domain_def(manager)) {
@@ -1050,6 +1051,8 @@ static int tomoyo_update_manager_entry(c
 	saved_manager = tomoyo_save_name(manager);
 	if (!saved_manager)
 		return -ENOMEM;
+	if (!is_delete)
+		new_entry = kmalloc(sizeof(*new_entry), GFP_KERNEL);
 	/***** EXCLUSIVE SECTION START *****/
 	down_write(&tomoyo_policy_manager_list_lock);
 	list_for_each_entry(ptr, &tomoyo_policy_manager_list, list) {
@@ -1057,22 +1060,18 @@ static int tomoyo_update_manager_entry(c
 			continue;
 		ptr->is_deleted = is_delete;
 		error = 0;
-		goto out;
+		break;
 	}
-	if (is_delete) {
-		error = -ENOENT;
-		goto out;
+	if (!is_delete && error && tomoyo_memory_ok(new_entry)) {
+		new_entry->manager = saved_manager;
+		new_entry->is_domain = is_domain;
+		list_add_tail(&new_entry->list, &tomoyo_policy_manager_list);
+		new_entry = NULL;
+		error = 0;
 	}
-	new_entry = tomoyo_alloc_element(sizeof(*new_entry));
-	if (!new_entry)
-		goto out;
-	new_entry->manager = saved_manager;
-	new_entry->is_domain = is_domain;
-	list_add_tail(&new_entry->list, &tomoyo_policy_manager_list);
-	error = 0;
- out:
 	up_write(&tomoyo_policy_manager_list_lock);
 	/***** EXCLUSIVE SECTION END *****/
+	kfree(new_entry);
 	return error;
 }
 
@@ -2050,35 +2049,6 @@ static int tomoyo_close_control(struct f
 }
 
 /**
- * tomoyo_alloc_acl_element - Allocate permanent memory for ACL entry.
- *
- * @acl_type:  Type of ACL entry.
- *
- * Returns pointer to the ACL entry on success, NULL otherwise.
- */
-void *tomoyo_alloc_acl_element(const u8 acl_type)
-{
-	int len;
-	struct tomoyo_acl_info *ptr;
-
-	switch (acl_type) {
-	case TOMOYO_TYPE_SINGLE_PATH_ACL:
-		len = sizeof(struct tomoyo_single_path_acl_record);
-		break;
-	case TOMOYO_TYPE_DOUBLE_PATH_ACL:
-		len = sizeof(struct tomoyo_double_path_acl_record);
-		break;
-	default:
-		return NULL;
-	}
-	ptr = tomoyo_alloc_element(len);
-	if (!ptr)
-		return NULL;
-	ptr->type = acl_type;
-	return ptr;
-}
-
-/**
  * tomoyo_open - open() for /sys/kernel/security/tomoyo/ interface.
  *
  * @inode: Pointer to "struct inode".
--- security-testing-2.6.git.orig/security/tomoyo/common.h
+++ security-testing-2.6.git/security/tomoyo/common.h
@@ -266,8 +266,6 @@ struct tomoyo_domain_info *tomoyo_find_o
 /* Check mode for specified functionality. */
 unsigned int tomoyo_check_flags(const struct tomoyo_domain_info *domain,
 				const u8 index);
-/* Allocate memory for structures. */
-void *tomoyo_alloc_acl_element(const u8 acl_type);
 /* Fill in "struct tomoyo_path_info" members. */
 void tomoyo_fill_path_info(struct tomoyo_path_info *ptr);
 /* Run policy loader when /sbin/init starts. */
--- security-testing-2.6.git.orig/security/tomoyo/domain.c
+++ security-testing-2.6.git/security/tomoyo/domain.c
@@ -113,11 +113,11 @@ static int tomoyo_update_domain_initiali
 						  const bool is_not,
 						  const bool is_delete)
 {
-	struct tomoyo_domain_initializer_entry *new_entry;
+	struct tomoyo_domain_initializer_entry *new_entry = NULL;
 	struct tomoyo_domain_initializer_entry *ptr;
 	const struct tomoyo_path_info *saved_program;
 	const struct tomoyo_path_info *saved_domainname = NULL;
-	int error = -ENOMEM;
+	int error = is_delete ? -ENOENT : -ENOMEM;
 	bool is_last_name = false;
 
 	if (!tomoyo_is_correct_path(program, 1, -1, -1, __func__))
@@ -135,6 +135,8 @@ static int tomoyo_update_domain_initiali
 	saved_program = tomoyo_save_name(program);
 	if (!saved_program)
 		return -ENOMEM;
+	if (!is_delete)
+		new_entry = kmalloc(sizeof(*new_entry), GFP_KERNEL);
 	/***** EXCLUSIVE SECTION START *****/
 	down_write(&tomoyo_domain_initializer_list_lock);
 	list_for_each_entry(ptr, &tomoyo_domain_initializer_list, list) {
@@ -144,24 +146,21 @@ static int tomoyo_update_domain_initiali
 			continue;
 		ptr->is_deleted = is_delete;
 		error = 0;
-		goto out;
+		break;
 	}
-	if (is_delete) {
-		error = -ENOENT;
-		goto out;
+	if (!is_delete && error && tomoyo_memory_ok(new_entry)) {
+		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);
+		new_entry = NULL;
+		error = 0;
 	}
-	new_entry = tomoyo_alloc_element(sizeof(*new_entry));
-	if (!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);
-	error = 0;
- out:
 	up_write(&tomoyo_domain_initializer_list_lock);
 	/***** EXCLUSIVE SECTION END *****/
+	kfree(new_entry);
 	return error;
 }
 
@@ -292,12 +291,12 @@ static int tomoyo_update_domain_keeper_e
 					     const bool is_not,
 					     const bool is_delete)
 {
-	struct tomoyo_domain_keeper_entry *new_entry;
+	struct tomoyo_domain_keeper_entry *new_entry = NULL;
 	struct tomoyo_domain_keeper_entry *ptr;
 	const struct tomoyo_path_info *saved_domainname;
 	const struct tomoyo_path_info *saved_program = NULL;
 	static DEFINE_MUTEX(lock);
-	int error = -ENOMEM;
+	int error = is_delete ? -ENOENT : -ENOMEM;
 	bool is_last_name = false;
 
 	if (!tomoyo_is_domain_def(domainname) &&
@@ -315,6 +314,8 @@ static int tomoyo_update_domain_keeper_e
 	saved_domainname = tomoyo_save_name(domainname);
 	if (!saved_domainname)
 		return -ENOMEM;
+	if (!is_delete)
+		new_entry = kmalloc(sizeof(*new_entry), GFP_KERNEL);
 	/***** EXCLUSIVE SECTION START *****/
 	down_write(&tomoyo_domain_keeper_list_lock);
 	list_for_each_entry(ptr, &tomoyo_domain_keeper_list, list) {
@@ -324,24 +325,20 @@ static int tomoyo_update_domain_keeper_e
 			continue;
 		ptr->is_deleted = is_delete;
 		error = 0;
-		goto out;
+		break;
 	}
-	if (is_delete) {
-		error = -ENOENT;
-		goto out;
+	if (!is_delete && error && tomoyo_memory_ok(new_entry)) {
+		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);
+		new_entry = NULL;
+		error = 0;
 	}
-	new_entry = tomoyo_alloc_element(sizeof(*new_entry));
-	if (!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);
-	error = 0;
- out:
 	up_write(&tomoyo_domain_keeper_list_lock);
 	/***** EXCLUSIVE SECTION END *****/
+	kfree(new_entry);
 	return error;
 }
 
@@ -463,11 +460,11 @@ static int tomoyo_update_alias_entry(con
 				     const char *aliased_name,
 				     const bool is_delete)
 {
-	struct tomoyo_alias_entry *new_entry;
+	struct tomoyo_alias_entry *new_entry = NULL;
 	struct tomoyo_alias_entry *ptr;
 	const struct tomoyo_path_info *saved_original_name;
 	const struct tomoyo_path_info *saved_aliased_name;
-	int error = -ENOMEM;
+	int error = is_delete ? -ENOENT : -ENOMEM;
 
 	if (!tomoyo_is_correct_path(original_name, 1, -1, -1, __func__) ||
 	    !tomoyo_is_correct_path(aliased_name, 1, -1, -1, __func__))
@@ -476,6 +473,8 @@ static int tomoyo_update_alias_entry(con
 	saved_aliased_name = tomoyo_save_name(aliased_name);
 	if (!saved_original_name || !saved_aliased_name)
 		return -ENOMEM;
+	if (!is_delete)
+		new_entry = kmalloc(sizeof(*new_entry), GFP_KERNEL);
 	/***** EXCLUSIVE SECTION START *****/
 	down_write(&tomoyo_alias_list_lock);
 	list_for_each_entry(ptr, &tomoyo_alias_list, list) {
@@ -484,22 +483,18 @@ static int tomoyo_update_alias_entry(con
 			continue;
 		ptr->is_deleted = is_delete;
 		error = 0;
-		goto out;
+		break;
 	}
-	if (is_delete) {
-		error = -ENOENT;
-		goto out;
+	if (!is_delete && error && tomoyo_memory_ok(new_entry)) {
+		new_entry->original_name = saved_original_name;
+		new_entry->aliased_name = saved_aliased_name;
+		list_add_tail(&new_entry->list, &tomoyo_alias_list);
+		new_entry = NULL;
+		error = 0;
 	}
-	new_entry = tomoyo_alloc_element(sizeof(*new_entry));
-	if (!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);
-	error = 0;
- out:
 	up_write(&tomoyo_alias_list_lock);
 	/***** EXCLUSIVE SECTION END *****/
+	kfree(new_entry);
 	return error;
 }
 
@@ -597,19 +592,21 @@ struct tomoyo_domain_info *tomoyo_find_o
 							    domainname,
 							    const u8 profile)
 {
-	struct tomoyo_domain_info *domain = NULL;
+	struct tomoyo_domain_info *new_domain = NULL;
+	struct tomoyo_domain_info *domain;
 	const struct tomoyo_path_info *saved_domainname;
 
+	if (!tomoyo_is_correct_domain(domainname, __func__))
+		return NULL;
+	saved_domainname = tomoyo_save_name(domainname);
+	if (!saved_domainname)
+		return NULL;
+	new_domain = kmalloc(sizeof(*new_domain), GFP_KERNEL);
 	/***** EXCLUSIVE SECTION START *****/
 	down_write(&tomoyo_domain_list_lock);
 	domain = tomoyo_find_domain(domainname);
 	if (domain)
 		goto out;
-	if (!tomoyo_is_correct_domain(domainname, __func__))
-		goto out;
-	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;
@@ -642,8 +639,9 @@ struct tomoyo_domain_info *tomoyo_find_o
 		goto out;
 	}
 	/* No memory reusable. Create using new memory. */
-	domain = tomoyo_alloc_element(sizeof(*domain));
-	if (domain) {
+	if (tomoyo_memory_ok(new_domain)) {
+		domain = new_domain;
+		new_domain = NULL;
 		INIT_LIST_HEAD(&domain->acl_info_list);
 		domain->domainname = saved_domainname;
 		domain->profile = profile;
@@ -652,6 +650,7 @@ struct tomoyo_domain_info *tomoyo_find_o
  out:
 	up_write(&tomoyo_domain_list_lock);
 	/***** EXCLUSIVE SECTION END *****/
+	kfree(new_domain);
 	return domain;
 }
 
--- security-testing-2.6.git.orig/security/tomoyo/file.c
+++ security-testing-2.6.git/security/tomoyo/file.c
@@ -156,16 +156,18 @@ static DECLARE_RWSEM(tomoyo_globally_rea
 static int tomoyo_update_globally_readable_entry(const char *filename,
 						 const bool is_delete)
 {
-	struct tomoyo_globally_readable_file_entry *new_entry;
+	struct tomoyo_globally_readable_file_entry *new_entry = NULL;
 	struct tomoyo_globally_readable_file_entry *ptr;
 	const struct tomoyo_path_info *saved_filename;
-	int error = -ENOMEM;
+	int error = is_delete ? -ENOENT : -ENOMEM;
 
 	if (!tomoyo_is_correct_path(filename, 1, 0, -1, __func__))
 		return -EINVAL;
 	saved_filename = tomoyo_save_name(filename);
 	if (!saved_filename)
 		return -ENOMEM;
+	if (!is_delete)
+		new_entry = kmalloc(sizeof(*new_entry), GFP_KERNEL);
 	/***** EXCLUSIVE SECTION START *****/
 	down_write(&tomoyo_globally_readable_list_lock);
 	list_for_each_entry(ptr, &tomoyo_globally_readable_list, list) {
@@ -173,21 +175,17 @@ static int tomoyo_update_globally_readab
 			continue;
 		ptr->is_deleted = is_delete;
 		error = 0;
-		goto out;
+		break;
 	}
-	if (is_delete) {
-		error = -ENOENT;
-		goto out;
+	if (!is_delete && error && tomoyo_memory_ok(new_entry)) {
+		new_entry->filename = saved_filename;
+		list_add_tail(&new_entry->list, &tomoyo_globally_readable_list);
+		new_entry = NULL;
+		error = 0;
 	}
-	new_entry = tomoyo_alloc_element(sizeof(*new_entry));
-	if (!new_entry)
-		goto out;
-	new_entry->filename = saved_filename;
-	list_add_tail(&new_entry->list, &tomoyo_globally_readable_list);
-	error = 0;
- out:
 	up_write(&tomoyo_globally_readable_list_lock);
 	/***** EXCLUSIVE SECTION END *****/
+	kfree(new_entry);
 	return error;
 }
 
@@ -274,16 +272,18 @@ static DECLARE_RWSEM(tomoyo_pattern_list
 static int tomoyo_update_file_pattern_entry(const char *pattern,
 					    const bool is_delete)
 {
-	struct tomoyo_pattern_entry *new_entry;
+	struct tomoyo_pattern_entry *new_entry = NULL;
 	struct tomoyo_pattern_entry *ptr;
 	const struct tomoyo_path_info *saved_pattern;
-	int error = -ENOMEM;
+	int error = is_delete ? -ENOENT : -ENOMEM;
 
 	if (!tomoyo_is_correct_path(pattern, 0, 1, 0, __func__))
 		return -EINVAL;
 	saved_pattern = tomoyo_save_name(pattern);
 	if (!saved_pattern)
 		return -ENOMEM;
+	if (!is_delete)
+		new_entry = kmalloc(sizeof(*new_entry), GFP_KERNEL);
 	/***** EXCLUSIVE SECTION START *****/
 	down_write(&tomoyo_pattern_list_lock);
 	list_for_each_entry(ptr, &tomoyo_pattern_list, list) {
@@ -291,21 +291,17 @@ static int tomoyo_update_file_pattern_en
 			continue;
 		ptr->is_deleted = is_delete;
 		error = 0;
-		goto out;
+		break;
 	}
-	if (is_delete) {
-		error = -ENOENT;
-		goto out;
+	if (!is_delete && error && tomoyo_memory_ok(new_entry)) {
+		new_entry->pattern = saved_pattern;
+		list_add_tail(&new_entry->list, &tomoyo_pattern_list);
+		new_entry = NULL;
+		error = 0;
 	}
-	new_entry = tomoyo_alloc_element(sizeof(*new_entry));
-	if (!new_entry)
-		goto out;
-	new_entry->pattern = saved_pattern;
-	list_add_tail(&new_entry->list, &tomoyo_pattern_list);
-	error = 0;
- out:
 	up_write(&tomoyo_pattern_list_lock);
 	/***** EXCLUSIVE SECTION END *****/
+	kfree(new_entry);
 	return error;
 }
 
@@ -398,15 +394,18 @@ static DECLARE_RWSEM(tomoyo_no_rewrite_l
 static int tomoyo_update_no_rewrite_entry(const char *pattern,
 					  const bool is_delete)
 {
-	struct tomoyo_no_rewrite_entry *new_entry, *ptr;
+	struct tomoyo_no_rewrite_entry *new_entry = NULL;
+	struct tomoyo_no_rewrite_entry *ptr;
 	const struct tomoyo_path_info *saved_pattern;
-	int error = -ENOMEM;
+	int error = is_delete ? -ENOENT : -ENOMEM;
 
 	if (!tomoyo_is_correct_path(pattern, 0, 0, 0, __func__))
 		return -EINVAL;
 	saved_pattern = tomoyo_save_name(pattern);
 	if (!saved_pattern)
 		return -ENOMEM;
+	if (!is_delete)
+		new_entry = kmalloc(sizeof(*new_entry), GFP_KERNEL);
 	/***** EXCLUSIVE SECTION START *****/
 	down_write(&tomoyo_no_rewrite_list_lock);
 	list_for_each_entry(ptr, &tomoyo_no_rewrite_list, list) {
@@ -414,21 +413,17 @@ static int tomoyo_update_no_rewrite_entr
 			continue;
 		ptr->is_deleted = is_delete;
 		error = 0;
-		goto out;
+		break;
 	}
-	if (is_delete) {
-		error = -ENOENT;
-		goto out;
+	if (!is_delete && error && tomoyo_memory_ok(new_entry)) {
+		new_entry->pattern = saved_pattern;
+		list_add_tail(&new_entry->list, &tomoyo_no_rewrite_list);
+		new_entry = NULL;
+		error = 0;
 	}
-	new_entry = tomoyo_alloc_element(sizeof(*new_entry));
-	if (!new_entry)
-		goto out;
-	new_entry->pattern = saved_pattern;
-	list_add_tail(&new_entry->list, &tomoyo_no_rewrite_list);
-	error = 0;
- out:
 	up_write(&tomoyo_no_rewrite_list_lock);
 	/***** EXCLUSIVE SECTION END *****/
+	kfree(new_entry);
 	return error;
 }
 
@@ -734,8 +729,8 @@ static int tomoyo_update_single_path_acl
 		(1 << TOMOYO_TYPE_READ_ACL) | (1 << TOMOYO_TYPE_WRITE_ACL);
 	const struct tomoyo_path_info *saved_filename;
 	struct tomoyo_acl_info *ptr;
-	struct tomoyo_single_path_acl_record *acl;
-	int error = -ENOMEM;
+	struct tomoyo_single_path_acl_record *new_entry = NULL;
+	int error = is_delete ? -ENOENT : -ENOMEM;
 	const u16 perm = 1 << type;
 
 	if (!domain)
@@ -745,11 +740,14 @@ static int tomoyo_update_single_path_acl
 	saved_filename = tomoyo_save_name(filename);
 	if (!saved_filename)
 		return -ENOMEM;
+	if (!is_delete)
+		new_entry = kmalloc(sizeof(*new_entry), GFP_KERNEL);
 	/***** EXCLUSIVE SECTION START *****/
 	down_write(&tomoyo_domain_acl_info_list_lock);
 	if (is_delete)
 		goto delete;
 	list_for_each_entry(ptr, &domain->acl_info_list, list) {
+		struct tomoyo_single_path_acl_record *acl;
 		if (tomoyo_acl_type1(ptr) != TOMOYO_TYPE_SINGLE_PATH_ACL)
 			continue;
 		acl = container_of(ptr, struct tomoyo_single_path_acl_record,
@@ -766,22 +764,23 @@ static int tomoyo_update_single_path_acl
 			acl->perm |= rw_mask;
 		ptr->type &= ~TOMOYO_ACL_DELETED;
 		error = 0;
-		goto out;
+		break;
 	}
 	/* Not found. Append it to the tail. */
-	acl = tomoyo_alloc_acl_element(TOMOYO_TYPE_SINGLE_PATH_ACL);
-	if (!acl)
-		goto out;
-	acl->perm = perm;
-	if (perm == (1 << TOMOYO_TYPE_READ_WRITE_ACL))
-		acl->perm |= rw_mask;
-	acl->filename = saved_filename;
-	list_add_tail(&acl->head.list, &domain->acl_info_list);
-	error = 0;
+	if (error && tomoyo_memory_ok(new_entry)) {
+		new_entry->head.type = TOMOYO_TYPE_SINGLE_PATH_ACL;
+		new_entry->perm = perm;
+		if (perm == (1 << TOMOYO_TYPE_READ_WRITE_ACL))
+			new_entry->perm |= rw_mask;
+		new_entry->filename = saved_filename;
+		list_add_tail(&new_entry->head.list, &domain->acl_info_list);
+		new_entry = NULL;
+		error = 0;
+	}
 	goto out;
  delete:
-	error = -ENOENT;
 	list_for_each_entry(ptr, &domain->acl_info_list, list) {
+		struct tomoyo_single_path_acl_record *acl;
 		if (tomoyo_acl_type2(ptr) != TOMOYO_TYPE_SINGLE_PATH_ACL)
 			continue;
 		acl = container_of(ptr, struct tomoyo_single_path_acl_record,
@@ -801,6 +800,7 @@ static int tomoyo_update_single_path_acl
  out:
 	up_write(&tomoyo_domain_acl_info_list_lock);
 	/***** EXCLUSIVE SECTION END *****/
+	kfree(new_entry);
 	return error;
 }
 
@@ -823,8 +823,8 @@ static int tomoyo_update_double_path_acl
 	const struct tomoyo_path_info *saved_filename1;
 	const struct tomoyo_path_info *saved_filename2;
 	struct tomoyo_acl_info *ptr;
-	struct tomoyo_double_path_acl_record *acl;
-	int error = -ENOMEM;
+	struct tomoyo_double_path_acl_record *new_entry = NULL;
+	int error = is_delete ? -ENOENT : -ENOMEM;
 	const u8 perm = 1 << type;
 
 	if (!domain)
@@ -836,11 +836,14 @@ static int tomoyo_update_double_path_acl
 	saved_filename2 = tomoyo_save_name(filename2);
 	if (!saved_filename1 || !saved_filename2)
 		return -ENOMEM;
+	if (!is_delete)
+		new_entry = kmalloc(sizeof(*new_entry), GFP_KERNEL);
 	/***** EXCLUSIVE SECTION START *****/
 	down_write(&tomoyo_domain_acl_info_list_lock);
 	if (is_delete)
 		goto delete;
 	list_for_each_entry(ptr, &domain->acl_info_list, list) {
+		struct tomoyo_double_path_acl_record *acl;
 		if (tomoyo_acl_type1(ptr) != TOMOYO_TYPE_DOUBLE_PATH_ACL)
 			continue;
 		acl = container_of(ptr, struct tomoyo_double_path_acl_record,
@@ -854,21 +857,22 @@ static int tomoyo_update_double_path_acl
 		acl->perm |= perm;
 		ptr->type &= ~TOMOYO_ACL_DELETED;
 		error = 0;
-		goto out;
+		break;
 	}
 	/* Not found. Append it to the tail. */
-	acl = tomoyo_alloc_acl_element(TOMOYO_TYPE_DOUBLE_PATH_ACL);
-	if (!acl)
-		goto out;
-	acl->perm = perm;
-	acl->filename1 = saved_filename1;
-	acl->filename2 = saved_filename2;
-	list_add_tail(&acl->head.list, &domain->acl_info_list);
-	error = 0;
+	if (error && tomoyo_memory_ok(new_entry)) {
+		new_entry->head.type = TOMOYO_TYPE_DOUBLE_PATH_ACL;
+		new_entry->perm = perm;
+		new_entry->filename1 = saved_filename1;
+		new_entry->filename2 = saved_filename2;
+		list_add_tail(&new_entry->head.list, &domain->acl_info_list);
+		new_entry = NULL;
+		error = 0;
+	}
 	goto out;
  delete:
-	error = -ENOENT;
 	list_for_each_entry(ptr, &domain->acl_info_list, list) {
+		struct tomoyo_double_path_acl_record *acl;
 		if (tomoyo_acl_type2(ptr) != TOMOYO_TYPE_DOUBLE_PATH_ACL)
 			continue;
 		acl = container_of(ptr, struct tomoyo_double_path_acl_record,
@@ -885,6 +889,7 @@ static int tomoyo_update_double_path_acl
  out:
 	up_write(&tomoyo_domain_acl_info_list_lock);
 	/***** EXCLUSIVE SECTION END *****/
+	kfree(new_entry);
 	return error;
 }
 
--- security-testing-2.6.git.orig/security/tomoyo/realpath.c
+++ security-testing-2.6.git/security/tomoyo/realpath.c
@@ -195,68 +195,36 @@ char *tomoyo_realpath_nofollow(const cha
 }
 
 /* Memory allocated for non-string data. */
-static unsigned int tomoyo_allocated_memory_for_elements;
+static atomic_t tomoyo_allocated_memory_for_elements;
 /* Quota for holding non-string data. */
 static unsigned int tomoyo_quota_for_elements;
 
 /**
- * tomoyo_alloc_element - Allocate permanent memory for structures.
+ * tomoyo_memory_ok - Check memory quota.
  *
- * @size: Size in bytes.
- *
- * Returns pointer to allocated memory on success, NULL otherwise.
+ * @ptr: Pointer to allocated memory.
  *
- * Memory has to be zeroed.
- * The RAM is chunked, so NEVER try to kfree() the returned pointer.
+ * Returns true if @ptr is not NULL and quota not exceeded, false otehrwise.
  */
-void *tomoyo_alloc_element(const unsigned int size)
+bool tomoyo_memory_ok(void *ptr)
 {
-	static char *buf;
-	static DEFINE_MUTEX(lock);
-	static unsigned int buf_used_len = PATH_MAX;
-	char *ptr = NULL;
-	/*Assumes sizeof(void *) >= sizeof(long) is true. */
-	const unsigned int word_aligned_size
-		= roundup(size, max(sizeof(void *), sizeof(long)));
-	if (word_aligned_size > PATH_MAX)
-		return NULL;
-	/***** EXCLUSIVE SECTION START *****/
-	mutex_lock(&lock);
-	if (buf_used_len + word_aligned_size > PATH_MAX) {
-		if (!tomoyo_quota_for_elements ||
-		    tomoyo_allocated_memory_for_elements
-		    + PATH_MAX <= tomoyo_quota_for_elements)
-			ptr = kzalloc(PATH_MAX, GFP_KERNEL);
-		if (!ptr) {
-			printk(KERN_WARNING "ERROR: Out of memory "
-			       "for tomoyo_alloc_element().\n");
-			if (!tomoyo_policy_loaded)
-				panic("MAC Initialization failed.\n");
-		} else {
-			buf = ptr;
-			tomoyo_allocated_memory_for_elements += PATH_MAX;
-			buf_used_len = word_aligned_size;
-			ptr = buf;
-		}
-	} else if (word_aligned_size) {
-		int i;
-		ptr = buf + buf_used_len;
-		buf_used_len += word_aligned_size;
-		for (i = 0; i < word_aligned_size; i++) {
-			if (!ptr[i])
-				continue;
-			printk(KERN_ERR "WARNING: Reserved memory was tainted! "
-			       "The system might go wrong.\n");
-			ptr[i] = '\0';
-		}
-	}
-	mutex_unlock(&lock);
-	/***** EXCLUSIVE SECTION END *****/
-	return ptr;
+	const int len = ptr ? ksize(ptr) : 0;
+	atomic_add(len, &tomoyo_allocated_memory_for_elements);
+	if (len && (!tomoyo_quota_for_elements ||
+		    atomic_read(&tomoyo_allocated_memory_for_elements)
+		    <= tomoyo_quota_for_elements)) {
+		memset(ptr, 0, len);
+		return true;
+	}
+	atomic_sub(len, &tomoyo_allocated_memory_for_elements);
+	printk(KERN_WARNING "ERROR: Out of memory. (%s)\n", __func__);
+	if (!tomoyo_policy_loaded)
+		panic("MAC Initialization failed.\n");
+	return false;
 }
 
 /* Memory allocated for string data in bytes. */
-static unsigned int tomoyo_allocated_memory_for_savename;
+static atomic_t tomoyo_allocated_memory_for_savename;
 /* Quota for holding string data in bytes. */
 static unsigned int tomoyo_quota_for_savename;
 
@@ -273,13 +241,6 @@ struct tomoyo_name_entry {
 	struct tomoyo_path_info entry;
 };
 
-/* Structure for available memory region. */
-struct tomoyo_free_memory_block_list {
-	struct list_head list;
-	char *ptr;             /* Pointer to a free area. */
-	int len;               /* Length of the area.     */
-};
-
 /*
  * The list for "struct tomoyo_name_entry".
  *
@@ -299,75 +260,57 @@ static struct list_head tomoyo_name_list
  */
 const struct tomoyo_path_info *tomoyo_save_name(const char *name)
 {
-	static LIST_HEAD(fmb_list);
 	static DEFINE_MUTEX(lock);
+	struct tomoyo_name_entry *entry;
 	struct tomoyo_name_entry *ptr;
 	unsigned int hash;
-	/* fmb contains available size in bytes.
-	   fmb is removed from the fmb_list when fmb->len becomes 0. */
-	struct tomoyo_free_memory_block_list *fmb;
-	int len;
-	char *cp;
+	const int len = name ? strlen(name) + 1 : 0;
+	int allocated_len;
+	int error = -ENOMEM;
 
-	if (!name)
+	if (!len)
 		return NULL;
-	len = strlen(name) + 1;
 	if (len > TOMOYO_MAX_PATHNAME_LEN) {
-		printk(KERN_WARNING "ERROR: Name too long "
-		       "for tomoyo_save_name().\n");
+		printk(KERN_WARNING "ERROR: Name too long. (%s)\n", __func__);
 		return NULL;
 	}
 	hash = full_name_hash((const unsigned char *) name, len - 1);
+	entry = kmalloc(sizeof(*entry) + len, GFP_KERNEL);
+	allocated_len = entry ? ksize(entry) : 0;
 	/***** EXCLUSIVE SECTION START *****/
 	mutex_lock(&lock);
 	list_for_each_entry(ptr, &tomoyo_name_list[hash % TOMOYO_MAX_HASH],
 			     list) {
-		if (hash == ptr->entry.hash && !strcmp(name, ptr->entry.name))
-			goto out;
-	}
-	list_for_each_entry(fmb, &fmb_list, list) {
-		if (len <= fmb->len)
-			goto ready;
-	}
-	if (!tomoyo_quota_for_savename ||
-	    tomoyo_allocated_memory_for_savename + PATH_MAX
-	    <= tomoyo_quota_for_savename)
-		cp = kzalloc(PATH_MAX, GFP_KERNEL);
-	else
-		cp = NULL;
-	fmb = kzalloc(sizeof(*fmb), GFP_KERNEL);
-	if (!cp || !fmb) {
-		kfree(cp);
-		kfree(fmb);
-		printk(KERN_WARNING "ERROR: Out of memory "
-		       "for tomoyo_save_name().\n");
-		if (!tomoyo_policy_loaded)
-			panic("MAC Initialization failed.\n");
-		ptr = NULL;
-		goto out;
-	}
-	tomoyo_allocated_memory_for_savename += PATH_MAX;
-	list_add(&fmb->list, &fmb_list);
-	fmb->ptr = cp;
-	fmb->len = PATH_MAX;
- ready:
-	ptr = tomoyo_alloc_element(sizeof(*ptr));
-	if (!ptr)
-		goto out;
-	ptr->entry.name = fmb->ptr;
-	memmove(fmb->ptr, name, len);
-	tomoyo_fill_path_info(&ptr->entry);
-	fmb->ptr += len;
-	fmb->len -= len;
-	list_add_tail(&ptr->list, &tomoyo_name_list[hash % TOMOYO_MAX_HASH]);
-	if (fmb->len == 0) {
-		list_del(&fmb->list);
-		kfree(fmb);
+		if (hash != ptr->entry.hash || strcmp(name, ptr->entry.name))
+			continue;
+		error = 0;
+		break;
+	}
+	if (error && entry &&
+	    (!tomoyo_quota_for_savename ||
+	     atomic_read(&tomoyo_allocated_memory_for_savename) + allocated_len
+	     <= tomoyo_quota_for_savename)) {
+		atomic_add(allocated_len,
+			   &tomoyo_allocated_memory_for_savename);
+		ptr = entry;
+		memset(ptr, 0, sizeof(*ptr));
+		ptr->entry.name = ((char *) ptr) + sizeof(*ptr);
+		memmove((char *) ptr->entry.name, name, len);
+		tomoyo_fill_path_info(&ptr->entry);
+		list_add_tail(&ptr->list,
+			      &tomoyo_name_list[hash % TOMOYO_MAX_HASH]);
+		entry = NULL;
+		error = 0;
 	}
- out:
 	mutex_unlock(&lock);
 	/***** EXCLUSIVE SECTION END *****/
-	return ptr ? &ptr->entry : NULL;
+	kfree(entry);
+	if (!error)
+		return &ptr->entry;
+	printk(KERN_WARNING "ERROR: Out of memory. (%s)\n", __func__);
+	if (!tomoyo_policy_loaded)
+		panic("MAC Initialization failed.\n");
+	return NULL;
 }
 
 /**
@@ -433,9 +376,9 @@ int tomoyo_read_memory_counter(struct to
 {
 	if (!head->read_eof) {
 		const unsigned int shared
-			= tomoyo_allocated_memory_for_savename;
+			= atomic_read(&tomoyo_allocated_memory_for_savename);
 		const unsigned int private
-			= tomoyo_allocated_memory_for_elements;
+			= atomic_read(&tomoyo_allocated_memory_for_elements);
 		const unsigned int dynamic
 			= atomic_read(&tomoyo_dynamic_memory_size);
 		char buffer[64];
--- security-testing-2.6.git.orig/security/tomoyo/realpath.h
+++ security-testing-2.6.git/security/tomoyo/realpath.h
@@ -36,11 +36,8 @@ char *tomoyo_realpath_nofollow(const cha
 /* Same with tomoyo_realpath() except that the pathname is already solved. */
 char *tomoyo_realpath_from_path(struct path *path);
 
-/*
- * Allocate memory for ACL entry.
- * The RAM is chunked, so NEVER try to kfree() the returned pointer.
- */
-void *tomoyo_alloc_element(const unsigned int size);
+/* Check memory quota. */
+bool tomoyo_memory_ok(void *ptr);
 
 /*
  * Keep the given name on the RAM.
--
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