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authorAl Viro <viro@zeniv.linux.org.uk>2013-03-05 15:04:55 -0500
committerAl Viro <viro@zeniv.linux.org.uk>2013-03-05 15:14:16 -0500
commite1fd1f490fa4213bd3060efa823a39d299538f72 (patch)
tree8bed18bdf003822ef1a4946e734418cf88546c24 /ipc
parent4b377bab29e6a241db42f27541e7fb63713ee178 (diff)
downloadkernel-e1fd1f490fa4213bd3060efa823a39d299538f72.tar.gz
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 <viro@zeniv.linux.org.uk>
Diffstat (limited to 'ipc')
-rw-r--r--ipc/compat.c14
-rw-r--r--ipc/sem.c121
-rw-r--r--ipc/syscall.c6
3 files changed, 88 insertions, 53 deletions
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: