diff options
Diffstat (limited to 'ipc/sem.c')
-rw-r--r-- | ipc/sem.c | 121 |
1 files changed, 76 insertions, 45 deletions
diff --git a/ipc/sem.c b/ipc/sem.c index e7236df7a47..5b167d00efa 100644 --- a/ipc/sem.c +++ b/ipc/sem.c @@ -799,7 +799,7 @@ static unsigned long copy_semid_to_user(void __user *buf, struct semid64_ds *in, } 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; @@ -834,7 +834,7 @@ static int semctl_nolock(struct ipc_namespace *ns, int semid, } 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; } @@ -871,7 +871,7 @@ static int semctl_nolock(struct ipc_namespace *ns, int semid, tbuf.sem_ctime = sma->sem_ctime; tbuf.sem_nsems = sma->sem_nsems; sem_unlock(sma); - if (copy_semid_to_user (arg.buf, &tbuf, version)) + if (copy_semid_to_user(p, &tbuf, version)) return -EFAULT; return id; } @@ -883,8 +883,67 @@ out_unlock: return err; } +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; + 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)) + return PTR_ERR(sma); + + INIT_LIST_HEAD(&tasks); + nsems = sma->sem_nsems; + + err = -EACCES; + if (ipcperms(ns, &sma->sem_perm, S_IWUGO)) + goto out_unlock; + + 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, int version, union semun arg) + int cmd, void __user *p) { struct sem_array *sma; struct sem* curr; @@ -903,7 +962,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, err = -EACCES; if (ipcperms(ns, &sma->sem_perm, - (cmd == SETVAL || cmd == SETALL) ? S_IWUGO : S_IRUGO)) + cmd == SETALL ? S_IWUGO : S_IRUGO)) goto out_unlock; err = security_sem_semctl(sma, cmd); @@ -914,7 +973,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, switch (cmd) { case GETALL: { - ushort __user *array = arg.array; + ushort __user *array = p; int i; if(nsems > SEMMSL_FAST) { @@ -957,7 +1016,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, } } - 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; @@ -991,7 +1050,7 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, 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) @@ -1012,27 +1071,6 @@ static int semctl_main(struct ipc_namespace *ns, int semid, int semnum, 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); @@ -1076,7 +1114,7 @@ copy_semid_from_user(struct semid64_ds *out, void __user *buf, int version) * 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; @@ -1084,7 +1122,7 @@ static int semctl_down(struct ipc_namespace *ns, int semid, 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; } @@ -1120,11 +1158,11 @@ out_up: 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; @@ -1137,30 +1175,23 @@ SYSCALL_DEFINE(semctl)(int semid, int semnum, int cmd, union semun arg) 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; } } -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); /* 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, |