From e1fd1f490fa4213bd3060efa823a39d299538f72 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Tue, 5 Mar 2013 15:04:55 -0500 Subject: get rid of union semop in sys_semctl(2) arguments just have the bugger take unsigned long and deal with SETVAL case (when we use an int member in the union) explicitly. Signed-off-by: Al Viro --- ipc/compat.c | 14 ++++--- ipc/sem.c | 121 ++++++++++++++++++++++++++++++++++++---------------------- ipc/syscall.c | 6 +-- 3 files changed, 88 insertions(+), 53 deletions(-) (limited to 'ipc') diff --git a/ipc/compat.c b/ipc/compat.c index 6cb6a4df86e4..892f6585dd60 100644 --- a/ipc/compat.c +++ b/ipc/compat.c @@ -240,7 +240,7 @@ static inline int put_compat_semid_ds(struct semid64_ds *s, static long do_compat_semctl(int first, int second, int third, u32 pad) { - union semun fourth; + unsigned long fourth; int err, err2; struct semid64_ds s64; struct semid64_ds __user *up64; @@ -249,9 +249,13 @@ static long do_compat_semctl(int first, int second, int third, u32 pad) memset(&s64, 0, sizeof(s64)); if ((third & (~IPC_64)) == SETVAL) - fourth.val = (int) pad; +#ifdef __BIG_ENDIAN + fourth = (unsigned long)pad << 32; +#else + fourth = pad; +#endif else - fourth.__pad = compat_ptr(pad); + fourth = (unsigned long)compat_ptr(pad); switch (third & (~IPC_64)) { case IPC_INFO: case IPC_RMID: @@ -269,7 +273,7 @@ static long do_compat_semctl(int first, int second, int third, u32 pad) case IPC_STAT: case SEM_STAT: up64 = compat_alloc_user_space(sizeof(s64)); - fourth.__pad = up64; + fourth = (unsigned long)up64; err = sys_semctl(first, second, third, fourth); if (err < 0) break; @@ -295,7 +299,7 @@ static long do_compat_semctl(int first, int second, int third, u32 pad) if (err) break; - fourth.__pad = up64; + fourth = (unsigned long)up64; err = sys_semctl(first, second, third, fourth); break; diff --git a/ipc/sem.c b/ipc/sem.c index e7236df7a470..5b167d00efa6 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, diff --git a/ipc/syscall.c b/ipc/syscall.c index 0d1e32ce048e..52429489cde0 100644 --- a/ipc/syscall.c +++ b/ipc/syscall.c @@ -33,12 +33,12 @@ SYSCALL_DEFINE6(ipc, unsigned int, call, int, first, unsigned long, second, case SEMGET: return sys_semget(first, second, third); case SEMCTL: { - union semun fourth; + unsigned long arg; if (!ptr) return -EINVAL; - if (get_user(fourth.__pad, (void __user * __user *) ptr)) + if (get_user(arg, (unsigned long __user *) ptr)) return -EFAULT; - return sys_semctl(first, second, third, fourth); + return sys_semctl(first, second, third, arg); } case MSGSND: -- cgit v1.2.3-59-g8ed1b