[PATCH] TOMOYO: Bring memory allocation to outside semaphore

From: Tetsuo Handa
Date: Tue Oct 13 2009 - 07:42:33 EST


[PATCH] TOMOYO: Bring memory allocation to outside semaphore

This patch brings kmalloc(GFP_KERNEL) to outside rw_semaphores.

Since readers no longer need to call down_read()/up_read() and writers no
longer sleep inside down_write()/up_write(), this patch also replaces various
rw_semaphore with single tomoyo_policy_lock mutex.

Signed-off-by: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx>
---
security/tomoyo/common.c | 87 +++++++++----------------
security/tomoyo/common.h | 11 +--
security/tomoyo/domain.c | 137 ++++++++++++++++-----------------------
security/tomoyo/file.c | 124 ++++++++++++++++++++----------------
security/tomoyo/realpath.c | 155 +++++++++++++++------------------------------
security/tomoyo/realpath.h | 6 -
6 files changed, 216 insertions(+), 304 deletions(-)

--- security-testing-2.6.orig/security/tomoyo/common.c
+++ security-testing-2.6/security/tomoyo/common.c
@@ -908,25 +908,28 @@ bool tomoyo_domain_quota_is_ok(struct to
static struct tomoyo_profile *tomoyo_find_or_assign_new_profile(const unsigned
int profile)
{
- static DEFINE_MUTEX(lock);
- struct tomoyo_profile *ptr = NULL;
- int i;
+ struct tomoyo_profile *ptr;
+ struct tomoyo_profile *entry;

if (profile >= TOMOYO_MAX_PROFILES)
return NULL;
- 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:
- mutex_unlock(&lock);
+ return ptr;
+ entry = kmalloc(sizeof(*ptr), GFP_KERNEL);
+ mutex_lock(&tomoyo_policy_lock);
+ ptr = tomoyo_profile_ptr[profile];
+ if (!ptr && tomoyo_memory_ok(entry)) {
+ int i;
+ ptr = entry;
+ 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;
+ entry = NULL;
+ }
+ mutex_unlock(&tomoyo_policy_lock);
+ kfree(entry);
return ptr;
}

@@ -1107,7 +1110,6 @@ struct tomoyo_policy_manager_entry {
* # cat /sys/kernel/security/tomoyo/manager
*/
static LIST_HEAD(tomoyo_policy_manager_list);
-static DECLARE_RWSEM(tomoyo_policy_manager_list_lock);

/**
* tomoyo_update_manager_entry - Add a manager entry.
@@ -1120,7 +1122,7 @@ 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 *entry;
struct tomoyo_policy_manager_entry *ptr;
const struct tomoyo_path_info *saved_manager;
int error = -ENOMEM;
@@ -1137,7 +1139,8 @@ static int tomoyo_update_manager_entry(c
saved_manager = tomoyo_save_name(manager);
if (!saved_manager)
return -ENOMEM;
- down_write(&tomoyo_policy_manager_list_lock);
+ entry = kmalloc(sizeof(*entry), GFP_KERNEL);
+ mutex_lock(&tomoyo_policy_lock);
list_for_each_entry_rcu(ptr, &tomoyo_policy_manager_list, list) {
if (ptr->manager != saved_manager)
continue;
@@ -1149,15 +1152,16 @@ static int tomoyo_update_manager_entry(c
error = -ENOENT;
goto out;
}
- 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_rcu(&new_entry->list, &tomoyo_policy_manager_list);
- error = 0;
+ if (tomoyo_memory_ok(entry)) {
+ entry->manager = saved_manager;
+ entry->is_domain = is_domain;
+ list_add_tail_rcu(&entry->list, &tomoyo_policy_manager_list);
+ entry = NULL;
+ error = 0;
+ }
out:
- up_write(&tomoyo_policy_manager_list_lock);
+ mutex_unlock(&tomoyo_policy_lock);
+ kfree(entry);
return error;
}

@@ -1324,7 +1328,7 @@ static int tomoyo_delete_domain(char *do

name.name = domainname;
tomoyo_fill_path_info(&name);
- down_write(&tomoyo_domain_list_lock);
+ mutex_lock(&tomoyo_policy_lock);
/* Is there an active domain? */
list_for_each_entry_rcu(domain, &tomoyo_domain_list, list) {
/* Never delete tomoyo_kernel_domain */
@@ -1336,7 +1340,7 @@ static int tomoyo_delete_domain(char *do
domain->is_deleted = true;
break;
}
- up_write(&tomoyo_domain_list_lock);
+ mutex_unlock(&tomoyo_policy_lock);
return 0;
}

@@ -2133,35 +2137,6 @@ 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.orig/security/tomoyo/common.h
+++ security-testing-2.6/security/tomoyo/common.h
@@ -307,6 +307,8 @@ bool tomoyo_is_correct_path(const char *
const char *function);
/* Check whether the token can be a domainname. */
bool tomoyo_is_domain_def(const unsigned char *buffer);
+/* Check memory quota. */
+bool tomoyo_memory_ok(void *ptr);
/* Check whether the given filename matches the given pattern. */
bool tomoyo_path_matches_pattern(const struct tomoyo_path_info *filename,
const struct tomoyo_path_info *pattern);
@@ -370,8 +372,6 @@ 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. */
@@ -423,12 +423,11 @@ static inline bool tomoyo_is_invalid(con
return c && (c <= ' ' || c >= 127);
}

+/* Lock for modifying policy. */
+extern struct mutex tomoyo_policy_lock;
+
/* The list for "struct tomoyo_domain_info". */
extern struct list_head tomoyo_domain_list;
-extern struct rw_semaphore tomoyo_domain_list_lock;
-
-/* Lock for domain->acl_info_list. */
-extern struct rw_semaphore tomoyo_domain_acl_info_list_lock;

/* Has /sbin/init started? */
extern bool tomoyo_policy_loaded;
--- security-testing-2.6.orig/security/tomoyo/domain.c
+++ security-testing-2.6/security/tomoyo/domain.c
@@ -58,7 +58,8 @@ struct tomoyo_domain_info tomoyo_kernel_
* exceptions.
*/
LIST_HEAD(tomoyo_domain_list);
-DECLARE_RWSEM(tomoyo_domain_list_lock);
+/* Lock for modifying policy. */
+DEFINE_MUTEX(tomoyo_policy_lock);

/*
* tomoyo_domain_initializer_entry is a structure which is used for holding
@@ -206,7 +207,6 @@ const char *tomoyo_get_last_name(const s
* 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.
@@ -223,7 +223,7 @@ 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 *entry = NULL;
struct tomoyo_domain_initializer_entry *ptr;
const struct tomoyo_path_info *saved_program;
const struct tomoyo_path_info *saved_domainname = NULL;
@@ -245,7 +245,9 @@ static int tomoyo_update_domain_initiali
saved_program = tomoyo_save_name(program);
if (!saved_program)
return -ENOMEM;
- down_write(&tomoyo_domain_initializer_list_lock);
+ if (!is_delete)
+ entry = kmalloc(sizeof(*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 ||
@@ -259,17 +261,19 @@ static int tomoyo_update_domain_initiali
error = -ENOENT;
goto out;
}
- 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_rcu(&new_entry->list, &tomoyo_domain_initializer_list);
- error = 0;
+ if (tomoyo_memory_ok(entry)) {
+ entry->domainname = saved_domainname;
+ entry->program = saved_program;
+ entry->is_not = is_not;
+ entry->is_last_name = is_last_name;
+ list_add_tail_rcu(&entry->list,
+ &tomoyo_domain_initializer_list);
+ entry = NULL;
+ error = 0;
+ }
out:
- up_write(&tomoyo_domain_initializer_list_lock);
+ mutex_unlock(&tomoyo_policy_lock);
+ kfree(entry);
return error;
}

@@ -415,7 +419,6 @@ static bool tomoyo_is_domain_initializer
* 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.
@@ -432,7 +435,7 @@ 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 *entry = NULL;
struct tomoyo_domain_keeper_entry *ptr;
const struct tomoyo_path_info *saved_domainname;
const struct tomoyo_path_info *saved_program = NULL;
@@ -454,7 +457,9 @@ static int tomoyo_update_domain_keeper_e
saved_domainname = tomoyo_save_name(domainname);
if (!saved_domainname)
return -ENOMEM;
- down_write(&tomoyo_domain_keeper_list_lock);
+ if (!is_delete)
+ entry = kmalloc(sizeof(*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 ||
@@ -468,17 +473,18 @@ static int tomoyo_update_domain_keeper_e
error = -ENOENT;
goto out;
}
- 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_rcu(&new_entry->list, &tomoyo_domain_keeper_list);
- error = 0;
+ if (tomoyo_memory_ok(entry)) {
+ entry->domainname = saved_domainname;
+ entry->program = saved_program;
+ entry->is_not = is_not;
+ entry->is_last_name = is_last_name;
+ list_add_tail_rcu(&entry->list, &tomoyo_domain_keeper_list);
+ entry = NULL;
+ error = 0;
+ }
out:
- up_write(&tomoyo_domain_keeper_list_lock);
+ mutex_unlock(&tomoyo_policy_lock);
+ kfree(entry);
return error;
}

@@ -609,7 +615,6 @@ static bool tomoyo_is_domain_keeper(cons
* 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.
@@ -624,7 +629,7 @@ 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 *entry = NULL;
struct tomoyo_alias_entry *ptr;
const struct tomoyo_path_info *saved_original_name;
const struct tomoyo_path_info *saved_aliased_name;
@@ -637,7 +642,9 @@ static int tomoyo_update_alias_entry(con
saved_aliased_name = tomoyo_save_name(aliased_name);
if (!saved_original_name || !saved_aliased_name)
return -ENOMEM;
- down_write(&tomoyo_alias_list_lock);
+ if (!is_delete)
+ entry = kmalloc(sizeof(*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)
@@ -650,15 +657,16 @@ static int tomoyo_update_alias_entry(con
error = -ENOENT;
goto out;
}
- 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_rcu(&new_entry->list, &tomoyo_alias_list);
- error = 0;
+ if (tomoyo_memory_ok(entry)) {
+ entry->original_name = saved_original_name;
+ entry->aliased_name = saved_aliased_name;
+ list_add_tail_rcu(&entry->list, &tomoyo_alias_list);
+ entry = NULL;
+ error = 0;
+ }
out:
- up_write(&tomoyo_alias_list_lock);
+ mutex_unlock(&tomoyo_policy_lock);
+ kfree(entry);
return error;
}

@@ -719,57 +727,28 @@ struct tomoyo_domain_info *tomoyo_find_o
domainname,
const u8 profile)
{
- struct tomoyo_domain_info *domain = NULL;
+ struct tomoyo_domain_info *entry;
+ struct tomoyo_domain_info *domain;
const struct tomoyo_path_info *saved_domainname;

- down_write(&tomoyo_domain_list_lock);
- domain = tomoyo_find_domain(domainname);
- if (domain)
- goto out;
if (!tomoyo_is_correct_domain(domainname, __func__))
- goto out;
+ return NULL;
saved_domainname = tomoyo_save_name(domainname);
if (!saved_domainname)
- goto out;
- /* Can I reuse memory of deleted domain? */
- list_for_each_entry_rcu(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_rcu(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) {
+ return NULL;
+ entry = kmalloc(sizeof(*entry), GFP_KERNEL);
+ mutex_lock(&tomoyo_policy_lock);
+ domain = tomoyo_find_domain(domainname);
+ if (!domain && tomoyo_memory_ok(entry)) {
+ domain = entry;
INIT_LIST_HEAD(&domain->acl_info_list);
domain->domainname = saved_domainname;
domain->profile = profile;
list_add_tail_rcu(&domain->list, &tomoyo_domain_list);
+ entry = NULL;
}
- out:
- up_write(&tomoyo_domain_list_lock);
+ mutex_unlock(&tomoyo_policy_lock);
+ kfree(entry);
return domain;
}

--- security-testing-2.6.orig/security/tomoyo/file.c
+++ security-testing-2.6/security/tomoyo/file.c
@@ -159,9 +159,6 @@ static struct tomoyo_path_info *tomoyo_g
return NULL;
}

-/* Lock for domain->acl_info_list. */
-DECLARE_RWSEM(tomoyo_domain_acl_info_list_lock);
-
static int tomoyo_update_double_path_acl(const u8 type, const char *filename1,
const char *filename2,
struct tomoyo_domain_info *
@@ -196,7 +193,6 @@ static int tomoyo_update_single_path_acl
* belongs to.
*/
static LIST_HEAD(tomoyo_globally_readable_list);
-static DECLARE_RWSEM(tomoyo_globally_readable_list_lock);

/**
* tomoyo_update_globally_readable_entry - Update "struct tomoyo_globally_readable_file_entry" list.
@@ -209,7 +205,7 @@ 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 *entry = NULL;
struct tomoyo_globally_readable_file_entry *ptr;
const struct tomoyo_path_info *saved_filename;
int error = -ENOMEM;
@@ -219,7 +215,9 @@ static int tomoyo_update_globally_readab
saved_filename = tomoyo_save_name(filename);
if (!saved_filename)
return -ENOMEM;
- down_write(&tomoyo_globally_readable_list_lock);
+ if (!is_delete)
+ entry = kmalloc(sizeof(*entry), GFP_KERNEL);
+ mutex_lock(&tomoyo_policy_lock);
list_for_each_entry_rcu(ptr, &tomoyo_globally_readable_list, list) {
if (ptr->filename != saved_filename)
continue;
@@ -231,14 +229,15 @@ static int tomoyo_update_globally_readab
error = -ENOENT;
goto out;
}
- new_entry = tomoyo_alloc_element(sizeof(*new_entry));
- if (!new_entry)
- goto out;
- new_entry->filename = saved_filename;
- list_add_tail_rcu(&new_entry->list, &tomoyo_globally_readable_list);
- error = 0;
+ if (tomoyo_memory_ok(entry)) {
+ entry->filename = saved_filename;
+ list_add_tail_rcu(&entry->list, &tomoyo_globally_readable_list);
+ entry = NULL;
+ error = 0;
+ }
out:
- up_write(&tomoyo_globally_readable_list_lock);
+ mutex_unlock(&tomoyo_policy_lock);
+ kfree(entry);
return error;
}

@@ -335,7 +334,6 @@ bool tomoyo_read_globally_readable_polic
* current process from accessing other process's information.
*/
static LIST_HEAD(tomoyo_pattern_list);
-static DECLARE_RWSEM(tomoyo_pattern_list_lock);

/**
* tomoyo_update_file_pattern_entry - Update "struct tomoyo_pattern_entry" list.
@@ -348,7 +346,7 @@ 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 *entry = NULL;
struct tomoyo_pattern_entry *ptr;
const struct tomoyo_path_info *saved_pattern;
int error = -ENOMEM;
@@ -358,7 +356,9 @@ static int tomoyo_update_file_pattern_en
saved_pattern = tomoyo_save_name(pattern);
if (!saved_pattern)
return -ENOMEM;
- down_write(&tomoyo_pattern_list_lock);
+ if (!is_delete)
+ entry = kmalloc(sizeof(*entry), GFP_KERNEL);
+ mutex_lock(&tomoyo_policy_lock);
list_for_each_entry_rcu(ptr, &tomoyo_pattern_list, list) {
if (saved_pattern != ptr->pattern)
continue;
@@ -370,14 +370,15 @@ static int tomoyo_update_file_pattern_en
error = -ENOENT;
goto out;
}
- new_entry = tomoyo_alloc_element(sizeof(*new_entry));
- if (!new_entry)
- goto out;
- new_entry->pattern = saved_pattern;
- list_add_tail_rcu(&new_entry->list, &tomoyo_pattern_list);
- error = 0;
+ if (tomoyo_memory_ok(entry)) {
+ entry->pattern = saved_pattern;
+ list_add_tail_rcu(&entry->list, &tomoyo_pattern_list);
+ entry = NULL;
+ error = 0;
+ }
out:
- up_write(&tomoyo_pattern_list_lock);
+ mutex_unlock(&tomoyo_policy_lock);
+ kfree(entry);
return error;
}

@@ -480,7 +481,6 @@ bool tomoyo_read_file_pattern(struct tom
* need to worry whether the file is already unlink()ed or not.
*/
static LIST_HEAD(tomoyo_no_rewrite_list);
-static DECLARE_RWSEM(tomoyo_no_rewrite_list_lock);

/**
* tomoyo_update_no_rewrite_entry - Update "struct tomoyo_no_rewrite_entry" list.
@@ -493,7 +493,8 @@ 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 *entry = NULL;
+ struct tomoyo_no_rewrite_entry *ptr;
const struct tomoyo_path_info *saved_pattern;
int error = -ENOMEM;

@@ -502,7 +503,9 @@ static int tomoyo_update_no_rewrite_entr
saved_pattern = tomoyo_save_name(pattern);
if (!saved_pattern)
return -ENOMEM;
- down_write(&tomoyo_no_rewrite_list_lock);
+ if (!is_delete)
+ entry = kmalloc(sizeof(*entry), GFP_KERNEL);
+ mutex_lock(&tomoyo_policy_lock);
list_for_each_entry_rcu(ptr, &tomoyo_no_rewrite_list, list) {
if (ptr->pattern != saved_pattern)
continue;
@@ -514,14 +517,15 @@ static int tomoyo_update_no_rewrite_entr
error = -ENOENT;
goto out;
}
- new_entry = tomoyo_alloc_element(sizeof(*new_entry));
- if (!new_entry)
- goto out;
- new_entry->pattern = saved_pattern;
- list_add_tail_rcu(&new_entry->list, &tomoyo_no_rewrite_list);
- error = 0;
+ if (tomoyo_memory_ok(entry)) {
+ entry->pattern = saved_pattern;
+ list_add_tail_rcu(&entry->list, &tomoyo_no_rewrite_list);
+ entry = NULL;
+ error = 0;
+ }
out:
- up_write(&tomoyo_no_rewrite_list_lock);
+ mutex_unlock(&tomoyo_policy_lock);
+ kfree(entry);
return error;
}

@@ -821,6 +825,7 @@ static int tomoyo_update_single_path_acl
const struct tomoyo_path_info *saved_filename;
struct tomoyo_acl_info *ptr;
struct tomoyo_single_path_acl_record *acl;
+ struct tomoyo_single_path_acl_record *entry = NULL;
int error = -ENOMEM;
const u16 perm = 1 << type;

@@ -831,7 +836,9 @@ static int tomoyo_update_single_path_acl
saved_filename = tomoyo_save_name(filename);
if (!saved_filename)
return -ENOMEM;
- down_write(&tomoyo_domain_acl_info_list_lock);
+ if (!is_delete)
+ entry = kmalloc(sizeof(*entry), GFP_KERNEL);
+ mutex_lock(&tomoyo_policy_lock);
if (is_delete)
goto delete;
list_for_each_entry_rcu(ptr, &domain->acl_info_list, list) {
@@ -854,15 +861,17 @@ static int tomoyo_update_single_path_acl
goto out;
}
/* 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_rcu(&acl->head.list, &domain->acl_info_list);
- error = 0;
+ if (tomoyo_memory_ok(entry)) {
+ acl = entry;
+ acl->head.type = TOMOYO_TYPE_SINGLE_PATH_ACL;
+ acl->perm = perm;
+ if (perm == (1 << TOMOYO_TYPE_READ_WRITE_ACL))
+ acl->perm |= rw_mask;
+ acl->filename = saved_filename;
+ list_add_tail_rcu(&acl->head.list, &domain->acl_info_list);
+ entry = NULL;
+ error = 0;
+ }
goto out;
delete:
error = -ENOENT;
@@ -884,7 +893,8 @@ static int tomoyo_update_single_path_acl
break;
}
out:
- up_write(&tomoyo_domain_acl_info_list_lock);
+ mutex_unlock(&tomoyo_policy_lock);
+ kfree(entry);
return error;
}

@@ -908,6 +918,7 @@ static int tomoyo_update_double_path_acl
const struct tomoyo_path_info *saved_filename2;
struct tomoyo_acl_info *ptr;
struct tomoyo_double_path_acl_record *acl;
+ struct tomoyo_double_path_acl_record *entry = NULL;
int error = -ENOMEM;
const u8 perm = 1 << type;

@@ -920,7 +931,9 @@ static int tomoyo_update_double_path_acl
saved_filename2 = tomoyo_save_name(filename2);
if (!saved_filename1 || !saved_filename2)
return -ENOMEM;
- down_write(&tomoyo_domain_acl_info_list_lock);
+ if (!is_delete)
+ entry = kmalloc(sizeof(*entry), GFP_KERNEL);
+ mutex_lock(&tomoyo_policy_lock);
if (is_delete)
goto delete;
list_for_each_entry_rcu(ptr, &domain->acl_info_list, list) {
@@ -940,14 +953,16 @@ static int tomoyo_update_double_path_acl
goto out;
}
/* 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_rcu(&acl->head.list, &domain->acl_info_list);
- error = 0;
+ if (tomoyo_memory_ok(entry)) {
+ acl = entry;
+ acl->head.type = TOMOYO_TYPE_DOUBLE_PATH_ACL;
+ acl->perm = perm;
+ acl->filename1 = saved_filename1;
+ acl->filename2 = saved_filename2;
+ list_add_tail_rcu(&acl->head.list, &domain->acl_info_list);
+ entry = NULL;
+ error = 0;
+ }
goto out;
delete:
error = -ENOENT;
@@ -966,7 +981,8 @@ static int tomoyo_update_double_path_acl
break;
}
out:
- up_write(&tomoyo_domain_acl_info_list_lock);
+ mutex_unlock(&tomoyo_policy_lock);
+ kfree(entry);
return error;
}

--- security-testing-2.6.orig/security/tomoyo/realpath.c
+++ security-testing-2.6/security/tomoyo/realpath.c
@@ -17,6 +17,25 @@
#include "realpath.h"

/**
+ * tomoyo_warn_oom - Print wraning message if memory allocation failed.
+ *
+ * @function: Function name.
+ */
+static 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");
+}
+
+/**
* tomoyo_encode: Convert binary string to ascii string.
*
* @buffer: Buffer for ASCII string.
@@ -200,57 +219,26 @@ static unsigned int tomoyo_allocated_mem
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.
+ * @ptr: Pointer to allocated memory.
*
- * Returns pointer to allocated memory on success, NULL otherwise.
+ * Returns true if @ptr is not NULL and quota not exceeded, false otherwise.
*
- * Memory has to be zeroed.
- * The RAM is chunked, so NEVER try to kfree() the returned pointer.
+ * Caller holds to tomoyo_policy_lock mutex.
*/
-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;
- 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';
- }
+ const unsigned int s = ptr ? ksize(ptr) : 0;
+ if (ptr && (!tomoyo_quota_for_elements ||
+ tomoyo_allocated_memory_for_elements + s
+ <= tomoyo_quota_for_elements)) {
+ tomoyo_allocated_memory_for_elements += s;
+ memset(ptr, 0, s);
+ return true;
}
- mutex_unlock(&lock);
- return ptr;
+ tomoyo_warn_oom(__func__);
+ return false;
}

/* Memory allocated for string data in bytes. */
@@ -280,13 +268,6 @@ 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. */
-};
-
/*
* tomoyo_name_list is used for holding string data used by TOMOYO.
* Since same string data is likely used for multiple times (e.g.
@@ -294,6 +275,7 @@ struct tomoyo_free_memory_block_list {
* "const struct tomoyo_path_info *".
*/
static struct list_head tomoyo_name_list[TOMOYO_MAX_HASH];
+static DEFINE_MUTEX(tomoyo_name_list_lock);

/**
* tomoyo_save_name - Allocate permanent memory for string data.
@@ -306,72 +288,39 @@ 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 *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;
+ int allocated_len;

if (!name)
return NULL;
len = strlen(name) + 1;
- if (len > TOMOYO_MAX_PATHNAME_LEN) {
- printk(KERN_WARNING "ERROR: Name too long "
- "for tomoyo_save_name().\n");
- return NULL;
- }
hash = full_name_hash((const unsigned char *) name, len - 1);
- mutex_lock(&lock);
+ mutex_lock(&tomoyo_name_list_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;
+ list) {
+ if (hash != ptr->entry.hash || strcmp(name, ptr->entry.name))
+ continue;
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)
+ ptr = kzalloc(sizeof(*ptr) + len, GFP_KERNEL);
+ allocated_len = ptr ? ksize(ptr) : 0;
+ if (!ptr || (tomoyo_quota_for_savename &&
+ tomoyo_allocated_memory_for_savename + allocated_len
+ > tomoyo_quota_for_savename)) {
+ kfree(ptr);
+ ptr = NULL;
+ tomoyo_warn_oom(__func__);
goto out;
- ptr->entry.name = fmb->ptr;
- memmove(fmb->ptr, name, len);
+ }
+ tomoyo_allocated_memory_for_savename += allocated_len;
+ ptr->entry.name = ((char *) ptr) + sizeof(*ptr);
+ memmove((char *) ptr->entry.name, 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);
- }
out:
- mutex_unlock(&lock);
+ mutex_unlock(&tomoyo_name_list_lock);
return ptr ? &ptr->entry : NULL;
}

--- security-testing-2.6.orig/security/tomoyo/realpath.h
+++ security-testing-2.6/security/tomoyo/realpath.h
@@ -37,12 +37,6 @@ char *tomoyo_realpath_nofollow(const cha
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);
-
-/*
* Keep the given name on the RAM.
* The RAM is shared, so NEVER try to modify or kfree() the returned name.
*/
--
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