return container_of(ipcp, struct sem_array, sem_perm);
}
+static inline struct sem_array *sem_obtain_object(struct ipc_namespace *ns, int id)
+{
+ struct kern_ipc_perm *ipcp = ipc_obtain_object(&sem_ids(ns), id);
+
+ if (IS_ERR(ipcp))
+ return ERR_CAST(ipcp);
+
+ return container_of(ipcp, struct sem_array, sem_perm);
+}
+
static inline struct sem_array *sem_lock_check(struct ipc_namespace *ns,
int id)
{
struct kern_ipc_perm *ipcp = ipc_lock_check(&sem_ids(ns), id);
if (IS_ERR(ipcp))
- return (struct sem_array *)ipcp;
+ return ERR_CAST(ipcp);
+
+ return container_of(ipcp, struct sem_array, sem_perm);
+}
+
+static inline struct sem_array *sem_obtain_object_check(struct ipc_namespace *ns,
+ int id)
+{
+ struct kern_ipc_perm *ipcp = ipc_obtain_object_check(&sem_ids(ns), id);
+
+ if (IS_ERR(ipcp))
+ return ERR_CAST(ipcp);
return container_of(ipcp, struct sem_array, sem_perm);
}
ipc_unlock(&(sma)->sem_perm);
}
+/*
+ * Call inside the rcu read section.
+ */
+static inline void sem_getref(struct sem_array *sma)
+{
+ spin_lock(&(sma)->sem_perm.lock);
+ ipc_rcu_getref(sma);
+ ipc_unlock(&(sma)->sem_perm);
+}
+
static inline void sem_rmid(struct ipc_namespace *ns, struct sem_array *s)
{
ipc_rmid(&sem_ids(ns), &s->sem_perm);
}
static int semctl_nolock(struct ipc_namespace *ns, int semid,
- int cmd, int version, union semun arg)
+ int cmd, int version, void __user *p)
{
int err;
struct sem_array *sma;
}
max_id = ipc_get_maxid(&sem_ids(ns));
up_read(&sem_ids(ns).rw_mutex);
- if (copy_to_user (arg.__buf, &seminfo, sizeof(struct seminfo)))
+ if (copy_to_user(p, &seminfo, sizeof(struct seminfo)))
return -EFAULT;
return (max_id < 0) ? 0: max_id;
}
case SEM_STAT:
{
struct semid64_ds tbuf;
- int id;
+ int id = 0;
+
+ memset(&tbuf, 0, sizeof(tbuf));
if (cmd == SEM_STAT) {
- sma = sem_lock(ns, semid);
- if (IS_ERR(sma))
- return PTR_ERR(sma);
+ rcu_read_lock();
+ sma = sem_obtain_object(ns, semid);
+ if (IS_ERR(sma)) {
+ err = PTR_ERR(sma);
+ goto out_unlock;
+ }
id = sma->sem_perm.id;
} else {
- sma = sem_lock_check(ns, semid);
- if (IS_ERR(sma))
- return PTR_ERR(sma);
- id = 0;
+ rcu_read_lock();
+ sma = sem_obtain_object_check(ns, semid);
+ if (IS_ERR(sma)) {
+ err = PTR_ERR(sma);
+ goto out_unlock;
+ }
}
err = -EACCES;
if (err)
goto out_unlock;
- memset(&tbuf, 0, sizeof(tbuf));
-
kernel_to_ipc64_perm(&sma->sem_perm, &tbuf.sem_perm);
tbuf.sem_otime = sma->sem_otime;
tbuf.sem_ctime = sma->sem_ctime;
tbuf.sem_nsems = sma->sem_nsems;
- sem_unlock(sma);
- if (copy_semid_to_user (arg.buf, &tbuf, version))
+ rcu_read_unlock();
+ if (copy_semid_to_user(p, &tbuf, version))
return -EFAULT;
return id;
}
return -EINVAL;
}
out_unlock:
- sem_unlock(sma);
+ rcu_read_unlock();
return err;
}
-static int semctl_main(struct ipc_namespace *ns, int semid, int semnum,
- int cmd, int version, union semun arg)
+static int semctl_setval(struct ipc_namespace *ns, int semid, int semnum,
+ unsigned long arg)
{
+ struct sem_undo *un;
struct sem_array *sma;
struct sem* curr;
int err;
- ushort fast_sem_io[SEMMSL_FAST];
- ushort* sem_io = fast_sem_io;
int nsems;
struct list_head tasks;
+ int val;
+#if defined(CONFIG_64BIT) && defined(__BIG_ENDIAN)
+ /* big-endian 64bit */
+ val = arg >> 32;
+#else
+ /* 32bit or little-endian 64bit */
+ val = arg;
+#endif
sma = sem_lock_check(ns, semid);
if (IS_ERR(sma))
nsems = sma->sem_nsems;
err = -EACCES;
- if (ipcperms(ns, &sma->sem_perm,
- (cmd == SETVAL || cmd == SETALL) ? S_IWUGO : S_IRUGO))
+ if (ipcperms(ns, &sma->sem_perm, S_IWUGO))
goto out_unlock;
- err = security_sem_semctl(sma, cmd);
+ err = security_sem_semctl(sma, SETVAL);
if (err)
goto out_unlock;
+ err = -EINVAL;
+ if(semnum < 0 || semnum >= nsems)
+ goto out_unlock;
+
+ curr = &sma->sem_base[semnum];
+
+ err = -ERANGE;
+ if (val > SEMVMX || val < 0)
+ goto out_unlock;
+
+ assert_spin_locked(&sma->sem_perm.lock);
+ list_for_each_entry(un, &sma->list_id, list_id)
+ un->semadj[semnum] = 0;
+
+ curr->semval = val;
+ curr->sempid = task_tgid_vnr(current);
+ sma->sem_ctime = get_seconds();
+ /* maybe some queued-up processes were waiting for this */
+ do_smart_update(sma, NULL, 0, 0, &tasks);
+ err = 0;
+out_unlock:
+ sem_unlock(sma);
+ wake_up_sem_queue_do(&tasks);
+ return err;
+}
+
+static int semctl_main(struct ipc_namespace *ns, int semid, int semnum,
+ int cmd, void __user *p)
+{
+ struct sem_array *sma;
+ struct sem* curr;
+ int err, nsems;
+ ushort fast_sem_io[SEMMSL_FAST];
+ ushort* sem_io = fast_sem_io;
+ struct list_head tasks;
+
+ INIT_LIST_HEAD(&tasks);
+
+ rcu_read_lock();
+ sma = sem_obtain_object_check(ns, semid);
+ if (IS_ERR(sma)) {
+ rcu_read_unlock();
+ return PTR_ERR(sma);
+ }
+
+ nsems = sma->sem_nsems;
+
+ err = -EACCES;
+ if (ipcperms(ns, &sma->sem_perm,
+ cmd == SETALL ? S_IWUGO : S_IRUGO)) {
+ rcu_read_unlock();
+ goto out_wakeup;
+ }
+
+ err = security_sem_semctl(sma, cmd);
+ if (err) {
+ rcu_read_unlock();
+ goto out_wakeup;
+ }
+
err = -EACCES;
switch (cmd) {
case GETALL:
{
- ushort __user *array = arg.array;
+ ushort __user *array = p;
int i;
if(nsems > SEMMSL_FAST) {
- sem_getref_and_unlock(sma);
+ sem_getref(sma);
sem_io = ipc_alloc(sizeof(ushort)*nsems);
if(sem_io == NULL) {
}
}
+ spin_lock(&sma->sem_perm.lock);
for (i = 0; i < sma->sem_nsems; i++)
sem_io[i] = sma->sem_base[i].semval;
sem_unlock(sma);
int i;
struct sem_undo *un;
- sem_getref_and_unlock(sma);
+ ipc_rcu_getref(sma);
+ rcu_read_unlock();
if(nsems > SEMMSL_FAST) {
sem_io = ipc_alloc(sizeof(ushort)*nsems);
}
}
- if (copy_from_user (sem_io, arg.array, nsems*sizeof(ushort))) {
+ if (copy_from_user (sem_io, p, nsems*sizeof(ushort))) {
sem_putref(sma);
err = -EFAULT;
goto out_free;
err = 0;
goto out_unlock;
}
- /* GETVAL, GETPID, GETNCTN, GETZCNT, SETVAL: fall-through */
+ /* GETVAL, GETPID, GETNCTN, GETZCNT: fall-through */
}
err = -EINVAL;
- if(semnum < 0 || semnum >= nsems)
- goto out_unlock;
+ if (semnum < 0 || semnum >= nsems) {
+ rcu_read_unlock();
+ goto out_wakeup;
+ }
+ spin_lock(&sma->sem_perm.lock);
curr = &sma->sem_base[semnum];
switch (cmd) {
case GETZCNT:
err = count_semzcnt(sma,semnum);
goto out_unlock;
- case SETVAL:
- {
- int val = arg.val;
- struct sem_undo *un;
-
- err = -ERANGE;
- if (val > SEMVMX || val < 0)
- goto out_unlock;
-
- assert_spin_locked(&sma->sem_perm.lock);
- list_for_each_entry(un, &sma->list_id, list_id)
- un->semadj[semnum] = 0;
-
- curr->semval = val;
- curr->sempid = task_tgid_vnr(current);
- sma->sem_ctime = get_seconds();
- /* maybe some queued-up processes were waiting for this */
- do_smart_update(sma, NULL, 0, 0, &tasks);
- err = 0;
- goto out_unlock;
- }
}
+
out_unlock:
sem_unlock(sma);
+out_wakeup:
wake_up_sem_queue_do(&tasks);
-
out_free:
if(sem_io != fast_sem_io)
ipc_free(sem_io, sizeof(ushort)*nsems);
* NOTE: no locks must be held, the rw_mutex is taken inside this function.
*/
static int semctl_down(struct ipc_namespace *ns, int semid,
- int cmd, int version, union semun arg)
+ int cmd, int version, void __user *p)
{
struct sem_array *sma;
int err;
struct kern_ipc_perm *ipcp;
if(cmd == IPC_SET) {
- if (copy_semid_from_user(&semid64, arg.buf, version))
+ if (copy_semid_from_user(&semid64, p, version))
return -EFAULT;
}
- ipcp = ipcctl_pre_down(ns, &sem_ids(ns), semid, cmd,
- &semid64.sem_perm, 0);
+ ipcp = ipcctl_pre_down_nolock(ns, &sem_ids(ns), semid, cmd,
+ &semid64.sem_perm, 0);
if (IS_ERR(ipcp))
return PTR_ERR(ipcp);
sma = container_of(ipcp, struct sem_array, sem_perm);
err = security_sem_semctl(sma, cmd);
- if (err)
+ if (err) {
+ rcu_read_unlock();
goto out_unlock;
+ }
switch(cmd){
case IPC_RMID:
+ ipc_lock_object(&sma->sem_perm);
freeary(ns, ipcp);
goto out_up;
case IPC_SET:
+ ipc_lock_object(&sma->sem_perm);
err = ipc_update_perm(&semid64.sem_perm, ipcp);
if (err)
goto out_unlock;
sma->sem_ctime = get_seconds();
break;
default:
+ rcu_read_unlock();
err = -EINVAL;
+ goto out_up;
}
out_unlock:
return err;
}
-SYSCALL_DEFINE(semctl)(int semid, int semnum, int cmd, union semun arg)
+SYSCALL_DEFINE4(semctl, int, semid, int, semnum, int, cmd, unsigned long, arg)
{
- int err = -EINVAL;
int version;
struct ipc_namespace *ns;
+ void __user *p = (void __user *)arg;
if (semid < 0)
return -EINVAL;
case SEM_INFO:
case IPC_STAT:
case SEM_STAT:
- err = semctl_nolock(ns, semid, cmd, version, arg);
- return err;
+ return semctl_nolock(ns, semid, cmd, version, p);
case GETALL:
case GETVAL:
case GETPID:
case GETNCNT:
case GETZCNT:
- case SETVAL:
case SETALL:
- err = semctl_main(ns,semid,semnum,cmd,version,arg);
- return err;
+ return semctl_main(ns, semid, semnum, cmd, p);
+ case SETVAL:
+ return semctl_setval(ns, semid, semnum, arg);
case IPC_RMID:
case IPC_SET:
- err = semctl_down(ns, semid, cmd, version, arg);
- return err;
+ return semctl_down(ns, semid, cmd, version, p);
default:
return -EINVAL;
}
}
-#ifdef CONFIG_HAVE_SYSCALL_WRAPPERS
-asmlinkage long SyS_semctl(int semid, int semnum, int cmd, union semun arg)
-{
- return SYSC_semctl((int) semid, (int) semnum, (int) cmd, arg);
-}
-SYSCALL_ALIAS(sys_semctl, SyS_semctl);
-#endif
/* If the task doesn't already have a undo_list, then allocate one
* here. We guarantee there is only one thread using this undo list,
spin_unlock(&ulp->lock);
if (likely(un!=NULL))
goto out;
- rcu_read_unlock();
/* no undo structure around - allocate one. */
/* step 1: figure out the size of the semaphore array */
- sma = sem_lock_check(ns, semid);
- if (IS_ERR(sma))
+ sma = sem_obtain_object_check(ns, semid);
+ if (IS_ERR(sma)) {
+ rcu_read_unlock();
return ERR_CAST(sma);
+ }
nsems = sma->sem_nsems;
- sem_getref_and_unlock(sma);
+ ipc_rcu_getref(sma);
+ rcu_read_unlock();
/* step 2: allocate new undo structure */
new = kzalloc(sizeof(struct sem_undo) + sizeof(short)*nsems, GFP_KERNEL);
INIT_LIST_HEAD(&tasks);
- sma = sem_lock_check(ns, semid);
+ rcu_read_lock();
+ sma = sem_obtain_object_check(ns, semid);
if (IS_ERR(sma)) {
if (un)
rcu_read_unlock();
goto out_free;
}
+ error = -EFBIG;
+ if (max >= sma->sem_nsems) {
+ rcu_read_unlock();
+ goto out_wakeup;
+ }
+
+ error = -EACCES;
+ if (ipcperms(ns, &sma->sem_perm, alter ? S_IWUGO : S_IRUGO)) {
+ rcu_read_unlock();
+ goto out_wakeup;
+ }
+
+ error = security_sem_semop(sma, sops, nsops, alter);
+ if (error) {
+ rcu_read_unlock();
+ goto out_wakeup;
+ }
+
/*
* semid identifiers are not unique - find_alloc_undo may have
* allocated an undo structure, it was invalidated by an RMID
* "un" itself is guaranteed by rcu.
*/
error = -EIDRM;
+ ipc_lock_object(&sma->sem_perm);
if (un) {
if (un->semid == -1) {
rcu_read_unlock();
}
}
- error = -EFBIG;
- if (max >= sma->sem_nsems)
- goto out_unlock_free;
-
- error = -EACCES;
- if (ipcperms(ns, &sma->sem_perm, alter ? S_IWUGO : S_IRUGO))
- goto out_unlock_free;
-
- error = security_sem_semop(sma, sops, nsops, alter);
- if (error)
- goto out_unlock_free;
-
error = try_atomic_semop (sma, sops, nsops, un, task_tgid_vnr(current));
if (error <= 0) {
if (alter && error == 0)
out_unlock_free:
sem_unlock(sma);
-
+out_wakeup:
wake_up_sem_queue_do(&tasks);
out_free:
if(sops != fast_sops)