#include <linux/bitops.h>
#include <linux/key.h>
#include <linux/interrupt.h>
-#include <linux/module.h>
+#include <linux/export.h>
#include <linux/user_namespace.h>
-#include "cred-internals.h"
+/*
+ * userns count is 1 for root user, 1 for init_uts_ns,
+ * and 1 for... ?
+ */
struct user_namespace init_user_ns = {
.kref = {
- .refcount = ATOMIC_INIT(2),
+ .refcount = ATOMIC_INIT(3),
},
.creator = &root_user,
};
* when changing user ID's (ie setuid() and friends).
*/
+#define UIDHASH_BITS (CONFIG_BASE_SMALL ? 3 : 7)
+#define UIDHASH_SZ (1 << UIDHASH_BITS)
#define UIDHASH_MASK (UIDHASH_SZ - 1)
#define __uidhashfn(uid) (((uid >> UIDHASH_BITS) + uid) & UIDHASH_MASK)
-#define uidhashentry(ns, uid) ((ns)->uidhash_table + __uidhashfn((uid)))
+#define uidhashentry(uid) (uidhash_table + __uidhashfn((__kuid_val(uid))))
static struct kmem_cache *uid_cachep;
+struct hlist_head uidhash_table[UIDHASH_SZ];
/*
* The uidhash_lock is mostly taken from process context, but it is
*/
static DEFINE_SPINLOCK(uidhash_lock);
-/* root_user.__count is 2, 1 for init task cred, 1 for init_user_ns->creator */
+/* root_user.__count is 2, 1 for init task cred, 1 for init_user_ns->user_ns */
struct user_struct root_user = {
.__count = ATOMIC_INIT(2),
.processes = ATOMIC_INIT(1),
.files = ATOMIC_INIT(0),
.sigpending = ATOMIC_INIT(0),
.locked_shm = 0,
- .user_ns = &init_user_ns,
-#ifdef CONFIG_USER_SCHED
- .tg = &init_task_group,
-#endif
+ .uid = GLOBAL_ROOT_UID,
};
/*
hlist_del_init(&up->uidhash_node);
}
-static struct user_struct *uid_hash_find(uid_t uid, struct hlist_head *hashent)
+static struct user_struct *uid_hash_find(kuid_t uid, struct hlist_head *hashent)
{
struct user_struct *user;
struct hlist_node *h;
hlist_for_each_entry(user, h, hashent, uidhash_node) {
- if (user->uid == uid) {
+ if (uid_eq(user->uid, uid)) {
atomic_inc(&user->__count);
return user;
}
return NULL;
}
-#ifdef CONFIG_USER_SCHED
-
-static void sched_destroy_user(struct user_struct *up)
-{
- sched_destroy_group(up->tg);
-}
-
-static int sched_create_user(struct user_struct *up)
-{
- int rc = 0;
-
- up->tg = sched_create_group(&root_task_group);
- if (IS_ERR(up->tg))
- rc = -ENOMEM;
-
- set_tg_uid(up);
-
- return rc;
-}
-
-#else /* CONFIG_USER_SCHED */
-
-static void sched_destroy_user(struct user_struct *up) { }
-static int sched_create_user(struct user_struct *up) { return 0; }
-
-#endif /* CONFIG_USER_SCHED */
-
-#if defined(CONFIG_USER_SCHED) && defined(CONFIG_SYSFS)
-
-static struct kset *uids_kset; /* represents the /sys/kernel/uids/ directory */
-static DEFINE_MUTEX(uids_mutex);
-
-static inline void uids_mutex_lock(void)
-{
- mutex_lock(&uids_mutex);
-}
-
-static inline void uids_mutex_unlock(void)
-{
- mutex_unlock(&uids_mutex);
-}
-
-/* uid directory attributes */
-#ifdef CONFIG_FAIR_GROUP_SCHED
-static ssize_t cpu_shares_show(struct kobject *kobj,
- struct kobj_attribute *attr,
- char *buf)
-{
- struct user_struct *up = container_of(kobj, struct user_struct, kobj);
-
- return sprintf(buf, "%lu\n", sched_group_shares(up->tg));
-}
-
-static ssize_t cpu_shares_store(struct kobject *kobj,
- struct kobj_attribute *attr,
- const char *buf, size_t size)
-{
- struct user_struct *up = container_of(kobj, struct user_struct, kobj);
- unsigned long shares;
- int rc;
-
- sscanf(buf, "%lu", &shares);
-
- rc = sched_group_set_shares(up->tg, shares);
-
- return (rc ? rc : size);
-}
-
-static struct kobj_attribute cpu_share_attr =
- __ATTR(cpu_share, 0644, cpu_shares_show, cpu_shares_store);
-#endif
-
-#ifdef CONFIG_RT_GROUP_SCHED
-static ssize_t cpu_rt_runtime_show(struct kobject *kobj,
- struct kobj_attribute *attr,
- char *buf)
-{
- struct user_struct *up = container_of(kobj, struct user_struct, kobj);
-
- return sprintf(buf, "%ld\n", sched_group_rt_runtime(up->tg));
-}
-
-static ssize_t cpu_rt_runtime_store(struct kobject *kobj,
- struct kobj_attribute *attr,
- const char *buf, size_t size)
-{
- struct user_struct *up = container_of(kobj, struct user_struct, kobj);
- unsigned long rt_runtime;
- int rc;
-
- sscanf(buf, "%ld", &rt_runtime);
-
- rc = sched_group_set_rt_runtime(up->tg, rt_runtime);
-
- return (rc ? rc : size);
-}
-
-static struct kobj_attribute cpu_rt_runtime_attr =
- __ATTR(cpu_rt_runtime, 0644, cpu_rt_runtime_show, cpu_rt_runtime_store);
-
-static ssize_t cpu_rt_period_show(struct kobject *kobj,
- struct kobj_attribute *attr,
- char *buf)
-{
- struct user_struct *up = container_of(kobj, struct user_struct, kobj);
-
- return sprintf(buf, "%lu\n", sched_group_rt_period(up->tg));
-}
-
-static ssize_t cpu_rt_period_store(struct kobject *kobj,
- struct kobj_attribute *attr,
- const char *buf, size_t size)
-{
- struct user_struct *up = container_of(kobj, struct user_struct, kobj);
- unsigned long rt_period;
- int rc;
-
- sscanf(buf, "%lu", &rt_period);
-
- rc = sched_group_set_rt_period(up->tg, rt_period);
-
- return (rc ? rc : size);
-}
-
-static struct kobj_attribute cpu_rt_period_attr =
- __ATTR(cpu_rt_period, 0644, cpu_rt_period_show, cpu_rt_period_store);
-#endif
-
-/* default attributes per uid directory */
-static struct attribute *uids_attributes[] = {
-#ifdef CONFIG_FAIR_GROUP_SCHED
- &cpu_share_attr.attr,
-#endif
-#ifdef CONFIG_RT_GROUP_SCHED
- &cpu_rt_runtime_attr.attr,
- &cpu_rt_period_attr.attr,
-#endif
- NULL
-};
-
-/* the lifetime of user_struct is not managed by the core (now) */
-static void uids_release(struct kobject *kobj)
-{
- return;
-}
-
-static struct kobj_type uids_ktype = {
- .sysfs_ops = &kobj_sysfs_ops,
- .default_attrs = uids_attributes,
- .release = uids_release,
-};
-
-/*
- * Create /sys/kernel/uids/<uid>/cpu_share file for this user
- * We do not create this file for users in a user namespace (until
- * sysfs tagging is implemented).
- *
- * See Documentation/scheduler/sched-design-CFS.txt for ramifications.
- */
-static int uids_user_create(struct user_struct *up)
-{
- struct kobject *kobj = &up->kobj;
- int error;
-
- memset(kobj, 0, sizeof(struct kobject));
- if (up->user_ns != &init_user_ns)
- return 0;
- kobj->kset = uids_kset;
- error = kobject_init_and_add(kobj, &uids_ktype, NULL, "%d", up->uid);
- if (error) {
- kobject_put(kobj);
- goto done;
- }
-
- kobject_uevent(kobj, KOBJ_ADD);
-done:
- return error;
-}
-
-/* create these entries in sysfs:
- * "/sys/kernel/uids" directory
- * "/sys/kernel/uids/0" directory (for root user)
- * "/sys/kernel/uids/0/cpu_share" file (for root user)
- */
-int __init uids_sysfs_init(void)
-{
- uids_kset = kset_create_and_add("uids", NULL, kernel_kobj);
- if (!uids_kset)
- return -ENOMEM;
-
- return uids_user_create(&root_user);
-}
-
-/* work function to remove sysfs directory for a user and free up
- * corresponding structures.
- */
-static void remove_user_sysfs_dir(struct work_struct *w)
-{
- struct user_struct *up = container_of(w, struct user_struct, work);
- unsigned long flags;
- int remove_user = 0;
-
- if (up->user_ns != &init_user_ns)
- return;
- /* Make uid_hash_remove() + sysfs_remove_file() + kobject_del()
- * atomic.
- */
- uids_mutex_lock();
-
- local_irq_save(flags);
-
- if (atomic_dec_and_lock(&up->__count, &uidhash_lock)) {
- uid_hash_remove(up);
- remove_user = 1;
- spin_unlock_irqrestore(&uidhash_lock, flags);
- } else {
- local_irq_restore(flags);
- }
-
- if (!remove_user)
- goto done;
-
- kobject_uevent(&up->kobj, KOBJ_REMOVE);
- kobject_del(&up->kobj);
- kobject_put(&up->kobj);
-
- sched_destroy_user(up);
- key_put(up->uid_keyring);
- key_put(up->session_keyring);
- kmem_cache_free(uid_cachep, up);
-
-done:
- uids_mutex_unlock();
-}
-
-/* IRQs are disabled and uidhash_lock is held upon function entry.
- * IRQ state (as stored in flags) is restored and uidhash_lock released
- * upon function exit.
- */
-static void free_user(struct user_struct *up, unsigned long flags)
-{
- /* restore back the count */
- atomic_inc(&up->__count);
- spin_unlock_irqrestore(&uidhash_lock, flags);
-
- put_user_ns(up->user_ns);
- INIT_WORK(&up->work, remove_user_sysfs_dir);
- schedule_work(&up->work);
-}
-
-#else /* CONFIG_USER_SCHED && CONFIG_SYSFS */
-
-int uids_sysfs_init(void) { return 0; }
-static inline int uids_user_create(struct user_struct *up) { return 0; }
-static inline void uids_mutex_lock(void) { }
-static inline void uids_mutex_unlock(void) { }
-
/* IRQs are disabled and uidhash_lock is held upon function entry.
* IRQ state (as stored in flags) is restored and uidhash_lock released
* upon function exit.
*/
static void free_user(struct user_struct *up, unsigned long flags)
+ __releases(&uidhash_lock)
{
uid_hash_remove(up);
spin_unlock_irqrestore(&uidhash_lock, flags);
- sched_destroy_user(up);
key_put(up->uid_keyring);
key_put(up->session_keyring);
- put_user_ns(up->user_ns);
kmem_cache_free(uid_cachep, up);
}
-#endif
-
/*
* Locate the user_struct for the passed UID. If found, take a ref on it. The
* caller must undo that ref with free_uid().
*
* If the user_struct could not be found, return NULL.
*/
-struct user_struct *find_user(uid_t uid)
+struct user_struct *find_user(kuid_t uid)
{
struct user_struct *ret;
unsigned long flags;
- struct user_namespace *ns = current_user_ns();
spin_lock_irqsave(&uidhash_lock, flags);
- ret = uid_hash_find(uid, uidhashentry(ns, uid));
+ ret = uid_hash_find(uid, uidhashentry(uid));
spin_unlock_irqrestore(&uidhash_lock, flags);
return ret;
}
local_irq_restore(flags);
}
-struct user_struct *alloc_uid(struct user_namespace *ns, uid_t uid)
+struct user_struct *alloc_uid(kuid_t uid)
{
- struct hlist_head *hashent = uidhashentry(ns, uid);
+ struct hlist_head *hashent = uidhashentry(uid);
struct user_struct *up, *new;
- /* Make uid_hash_find() + uids_user_create() + uid_hash_insert()
- * atomic.
- */
- uids_mutex_lock();
-
spin_lock_irq(&uidhash_lock);
up = uid_hash_find(uid, hashent);
spin_unlock_irq(&uidhash_lock);
new->uid = uid;
atomic_set(&new->__count, 1);
- if (sched_create_user(new) < 0)
- goto out_free_user;
-
- new->user_ns = get_user_ns(ns);
-
- if (uids_user_create(new))
- goto out_destoy_sched;
-
/*
* Before adding this, check whether we raced
* on adding the same user already..
spin_lock_irq(&uidhash_lock);
up = uid_hash_find(uid, hashent);
if (up) {
- /* This case is not possible when CONFIG_USER_SCHED
- * is defined, since we serialize alloc_uid() using
- * uids_mutex. Hence no need to call
- * sched_destroy_user() or remove_user_sysfs_dir().
- */
key_put(new->uid_keyring);
key_put(new->session_keyring);
kmem_cache_free(uid_cachep, new);
spin_unlock_irq(&uidhash_lock);
}
- uids_mutex_unlock();
-
return up;
-out_destoy_sched:
- sched_destroy_user(new);
- put_user_ns(new->user_ns);
-out_free_user:
- kmem_cache_free(uid_cachep, new);
out_unlock:
- uids_mutex_unlock();
return NULL;
}
0, SLAB_HWCACHE_ALIGN|SLAB_PANIC, NULL);
for(n = 0; n < UIDHASH_SZ; ++n)
- INIT_HLIST_HEAD(init_user_ns.uidhash_table + n);
+ INIT_HLIST_HEAD(uidhash_table + n);
/* Insert the root user immediately (init already runs as root) */
spin_lock_irq(&uidhash_lock);
- uid_hash_insert(&root_user, uidhashentry(&init_user_ns, 0));
+ uid_hash_insert(&root_user, uidhashentry(GLOBAL_ROOT_UID));
spin_unlock_irq(&uidhash_lock);
return 0;
Code Review / linux-3.10.git / blobdiff