TOMOYO: Use mutex_lock_interruptible.

Some of TOMOYO's functions may sleep after mutex_lock(). If OOM-killer selected
a process which is waiting at mutex_lock(), the to-be-killed process can't be
killed. Thus, replace mutex_lock() with mutex_lock_interruptible() so that the
to-be-killed process can immediately return from TOMOYO's functions.

Signed-off-by: Tetsuo Handa <penguin-kernel@I-love.SAKURA.ne.jp>
Signed-off-by: James Morris <jmorris@namei.org>
This commit is contained in:
Tetsuo Handa 2010-05-06 00:18:15 +09:00 committed by James Morris
parent 2b9e4688fa
commit 2928238142
6 changed files with 37 additions and 24 deletions

View File

@ -874,13 +874,13 @@ bool tomoyo_domain_quota_is_ok(struct tomoyo_domain_info * const domain)
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;
if (profile >= TOMOYO_MAX_PROFILES)
return NULL;
mutex_lock(&lock);
if (mutex_lock_interruptible(&tomoyo_policy_lock))
return NULL;
ptr = tomoyo_profile_ptr[profile];
if (ptr)
goto ok;
@ -895,7 +895,7 @@ static struct tomoyo_profile *tomoyo_find_or_assign_new_profile(const unsigned
mb(); /* Avoid out-of-order execution. */
tomoyo_profile_ptr[profile] = ptr;
ok:
mutex_unlock(&lock);
mutex_unlock(&tomoyo_policy_lock);
return ptr;
}
@ -1090,7 +1090,8 @@ static int tomoyo_update_manager_entry(const char *manager,
return -ENOMEM;
if (!is_delete)
entry = kmalloc(sizeof(*entry), GFP_NOFS);
mutex_lock(&tomoyo_policy_lock);
if (mutex_lock_interruptible(&tomoyo_policy_lock))
goto out;
list_for_each_entry_rcu(ptr, &tomoyo_policy_manager_list, list) {
if (ptr->manager != saved_manager)
continue;
@ -1107,6 +1108,7 @@ static int tomoyo_update_manager_entry(const char *manager,
error = 0;
}
mutex_unlock(&tomoyo_policy_lock);
out:
tomoyo_put_name(saved_manager);
kfree(entry);
return error;
@ -1287,7 +1289,8 @@ static int tomoyo_delete_domain(char *domainname)
name.name = domainname;
tomoyo_fill_path_info(&name);
mutex_lock(&tomoyo_policy_lock);
if (mutex_lock_interruptible(&tomoyo_policy_lock))
return 0;
/* Is there an active domain? */
list_for_each_entry_rcu(domain, &tomoyo_domain_list, list) {
/* Never delete tomoyo_kernel_domain */

View File

@ -662,7 +662,6 @@ extern struct list_head tomoyo_pattern_list;
extern struct list_head tomoyo_no_rewrite_list;
extern struct list_head tomoyo_policy_manager_list;
extern struct list_head tomoyo_name_list[TOMOYO_MAX_HASH];
extern struct mutex tomoyo_name_list_lock;
/* Lock for protecting policy. */
extern struct mutex tomoyo_policy_lock;

View File

@ -154,7 +154,8 @@ static int tomoyo_update_domain_initializer_entry(const char *domainname,
goto out;
if (!is_delete)
entry = kmalloc(sizeof(*entry), GFP_NOFS);
mutex_lock(&tomoyo_policy_lock);
if (mutex_lock_interruptible(&tomoyo_policy_lock))
goto out;
list_for_each_entry_rcu(ptr, &tomoyo_domain_initializer_list, list) {
if (ptr->is_not != is_not ||
ptr->domainname != saved_domainname ||
@ -374,7 +375,8 @@ static int tomoyo_update_domain_keeper_entry(const char *domainname,
goto out;
if (!is_delete)
entry = kmalloc(sizeof(*entry), GFP_NOFS);
mutex_lock(&tomoyo_policy_lock);
if (mutex_lock_interruptible(&tomoyo_policy_lock))
goto out;
list_for_each_entry_rcu(ptr, &tomoyo_domain_keeper_list, list) {
if (ptr->is_not != is_not ||
ptr->domainname != saved_domainname ||
@ -566,7 +568,8 @@ static int tomoyo_update_alias_entry(const char *original_name,
goto out;
if (!is_delete)
entry = kmalloc(sizeof(*entry), GFP_NOFS);
mutex_lock(&tomoyo_policy_lock);
if (mutex_lock_interruptible(&tomoyo_policy_lock))
goto out;
list_for_each_entry_rcu(ptr, &tomoyo_alias_list, list) {
if (ptr->original_name != saved_original_name ||
ptr->aliased_name != saved_aliased_name)
@ -656,7 +659,7 @@ struct tomoyo_domain_info *tomoyo_find_or_assign_new_domain(const char *
const u8 profile)
{
struct tomoyo_domain_info *entry;
struct tomoyo_domain_info *domain;
struct tomoyo_domain_info *domain = NULL;
const struct tomoyo_path_info *saved_domainname;
bool found = false;
@ -666,7 +669,8 @@ struct tomoyo_domain_info *tomoyo_find_or_assign_new_domain(const char *
if (!saved_domainname)
return NULL;
entry = kzalloc(sizeof(*entry), GFP_NOFS);
mutex_lock(&tomoyo_policy_lock);
if (mutex_lock_interruptible(&tomoyo_policy_lock))
goto out;
list_for_each_entry_rcu(domain, &tomoyo_domain_list, list) {
if (domain->is_deleted ||
tomoyo_pathcmp(saved_domainname, domain->domainname))
@ -685,6 +689,7 @@ struct tomoyo_domain_info *tomoyo_find_or_assign_new_domain(const char *
found = true;
}
mutex_unlock(&tomoyo_policy_lock);
out:
tomoyo_put_name(saved_domainname);
kfree(entry);
return found ? domain : NULL;

View File

@ -176,7 +176,8 @@ static int tomoyo_update_globally_readable_entry(const char *filename,
return -ENOMEM;
if (!is_delete)
entry = kmalloc(sizeof(*entry), GFP_NOFS);
mutex_lock(&tomoyo_policy_lock);
if (mutex_lock_interruptible(&tomoyo_policy_lock))
goto out;
list_for_each_entry_rcu(ptr, &tomoyo_globally_readable_list, list) {
if (ptr->filename != saved_filename)
continue;
@ -192,6 +193,7 @@ static int tomoyo_update_globally_readable_entry(const char *filename,
error = 0;
}
mutex_unlock(&tomoyo_policy_lock);
out:
tomoyo_put_name(saved_filename);
kfree(entry);
return error;
@ -323,7 +325,8 @@ static int tomoyo_update_file_pattern_entry(const char *pattern,
goto out;
if (!is_delete)
entry = kmalloc(sizeof(*entry), GFP_NOFS);
mutex_lock(&tomoyo_policy_lock);
if (mutex_lock_interruptible(&tomoyo_policy_lock))
goto out;
list_for_each_entry_rcu(ptr, &tomoyo_pattern_list, list) {
if (saved_pattern != ptr->pattern)
continue;
@ -476,7 +479,8 @@ static int tomoyo_update_no_rewrite_entry(const char *pattern,
return error;
if (!is_delete)
entry = kmalloc(sizeof(*entry), GFP_NOFS);
mutex_lock(&tomoyo_policy_lock);
if (mutex_lock_interruptible(&tomoyo_policy_lock))
goto out;
list_for_each_entry_rcu(ptr, &tomoyo_no_rewrite_list, list) {
if (ptr->pattern != saved_pattern)
continue;
@ -492,6 +496,7 @@ static int tomoyo_update_no_rewrite_entry(const char *pattern,
error = 0;
}
mutex_unlock(&tomoyo_policy_lock);
out:
tomoyo_put_name(saved_pattern);
kfree(entry);
return error;
@ -822,7 +827,8 @@ static int tomoyo_update_path_acl(const u8 type, const char *filename,
return -ENOMEM;
if (!is_delete)
entry = kmalloc(sizeof(*entry), GFP_NOFS);
mutex_lock(&tomoyo_policy_lock);
if (mutex_lock_interruptible(&tomoyo_policy_lock))
goto out;
list_for_each_entry_rcu(ptr, &domain->acl_info_list, list) {
struct tomoyo_path_acl *acl =
container_of(ptr, struct tomoyo_path_acl, head);
@ -867,6 +873,7 @@ static int tomoyo_update_path_acl(const u8 type, const char *filename,
error = 0;
}
mutex_unlock(&tomoyo_policy_lock);
out:
kfree(entry);
tomoyo_put_name(saved_filename);
return error;
@ -908,7 +915,8 @@ static int tomoyo_update_path2_acl(const u8 type, const char *filename1,
goto out;
if (!is_delete)
entry = kmalloc(sizeof(*entry), GFP_NOFS);
mutex_lock(&tomoyo_policy_lock);
if (mutex_lock_interruptible(&tomoyo_policy_lock))
goto out;
list_for_each_entry_rcu(ptr, &domain->acl_info_list, list) {
struct tomoyo_path2_acl *acl =
container_of(ptr, struct tomoyo_path2_acl, head);

View File

@ -151,7 +151,8 @@ static void tomoyo_del_name(const struct tomoyo_name_entry *ptr)
static void tomoyo_collect_entry(void)
{
mutex_lock(&tomoyo_policy_lock);
if (mutex_lock_interruptible(&tomoyo_policy_lock))
return;
{
struct tomoyo_globally_readable_file_entry *ptr;
list_for_each_entry_rcu(ptr, &tomoyo_globally_readable_list,
@ -275,8 +276,6 @@ static void tomoyo_collect_entry(void)
break;
}
}
mutex_unlock(&tomoyo_policy_lock);
mutex_lock(&tomoyo_name_list_lock);
{
int i;
for (i = 0; i < TOMOYO_MAX_HASH; i++) {
@ -294,7 +293,7 @@ static void tomoyo_collect_entry(void)
}
}
}
mutex_unlock(&tomoyo_name_list_lock);
mutex_unlock(&tomoyo_policy_lock);
}
static void tomoyo_kfree_entry(void)

View File

@ -240,8 +240,6 @@ void tomoyo_memory_free(void *ptr)
* "const struct tomoyo_path_info *".
*/
struct list_head tomoyo_name_list[TOMOYO_MAX_HASH];
/* Lock for protecting tomoyo_name_list . */
DEFINE_MUTEX(tomoyo_name_list_lock);
/**
* tomoyo_get_name - Allocate permanent memory for string data.
@ -263,7 +261,8 @@ const struct tomoyo_path_info *tomoyo_get_name(const char *name)
len = strlen(name) + 1;
hash = full_name_hash((const unsigned char *) name, len - 1);
head = &tomoyo_name_list[hash_long(hash, TOMOYO_HASH_BITS)];
mutex_lock(&tomoyo_name_list_lock);
if (mutex_lock_interruptible(&tomoyo_policy_lock))
return NULL;
list_for_each_entry(ptr, head, list) {
if (hash != ptr->entry.hash || strcmp(name, ptr->entry.name))
continue;
@ -290,7 +289,7 @@ const struct tomoyo_path_info *tomoyo_get_name(const char *name)
tomoyo_fill_path_info(&ptr->entry);
list_add_tail(&ptr->list, head);
out:
mutex_unlock(&tomoyo_name_list_lock);
mutex_unlock(&tomoyo_policy_lock);
return ptr ? &ptr->entry : NULL;
}