semctl(): move compat to native

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

1 files changed, 94 insertions, 0 deletions

diff --git a/ipc/sem.c b/ipc/sem.c
index c8029c6bef72..fcf064d6046a 100644
--- a/ipc/sem.c
+++ b/ipc/sem.c
@@ -1617,6 +1617,100 @@ SYSCALL_DEFINE4(semctl, int, semid, int, semnum, int, cmd, unsigned long, arg)
 	}
 }
 
+#ifdef CONFIG_COMPAT
+
+struct compat_semid_ds {
+	struct compat_ipc_perm sem_perm;
+	compat_time_t sem_otime;
+	compat_time_t sem_ctime;
+	compat_uptr_t sem_base;
+	compat_uptr_t sem_pending;
+	compat_uptr_t sem_pending_last;
+	compat_uptr_t undo;
+	unsigned short sem_nsems;
+};
+
+static int copy_compat_semid_from_user(struct semid64_ds *out, void __user *buf,
+					int version)
+{
+	memset(out, 0, sizeof(*out));
+	if (version == IPC_64) {
+		struct compat_semid64_ds *p = buf;
+		return get_compat_ipc64_perm(&out->sem_perm, &p->sem_perm);
+	} else {
+		struct compat_semid_ds *p = buf;
+		return get_compat_ipc_perm(&out->sem_perm, &p->sem_perm);
+	}
+}
+
+static int copy_compat_semid_to_user(void __user *buf, struct semid64_ds *in,
+					int version)
+{
+	if (version == IPC_64) {
+		struct compat_semid64_ds v;
+		memset(&v, 0, sizeof(v));
+		to_compat_ipc64_perm(&v.sem_perm, &in->sem_perm);
+		v.sem_otime = in->sem_otime;
+		v.sem_ctime = in->sem_ctime;
+		v.sem_nsems = in->sem_nsems;
+		return copy_to_user(buf, &v, sizeof(v));
+	} else {
+		struct compat_semid_ds v;
+		memset(&v, 0, sizeof(v));
+		to_compat_ipc_perm(&v.sem_perm, &in->sem_perm);
+		v.sem_otime = in->sem_otime;
+		v.sem_ctime = in->sem_ctime;
+		v.sem_nsems = in->sem_nsems;
+		return copy_to_user(buf, &v, sizeof(v));
+	}
+}
+
+COMPAT_SYSCALL_DEFINE4(semctl, int, semid, int, semnum, int, cmd, int, arg)
+{
+	void __user *p = compat_ptr(arg);
+	struct ipc_namespace *ns;
+	struct semid64_ds semid64;
+	int version = compat_ipc_parse_version(&cmd);
+	int err;
+
+	ns = current->nsproxy->ipc_ns;
+
+	if (semid < 0)
+		return -EINVAL;
+
+	switch (cmd & (~IPC_64)) {
+	case IPC_INFO:
+	case SEM_INFO:
+		return semctl_info(ns, semid, cmd, p);
+	case IPC_STAT:
+	case SEM_STAT:
+		err = semctl_stat(ns, semid, cmd, &semid64);
+		if (err < 0)
+			return err;
+		if (copy_compat_semid_to_user(p, &semid64, version))
+			err = -EFAULT;
+		return err;
+	case GETVAL:
+	case GETPID:
+	case GETNCNT:
+	case GETZCNT:
+	case GETALL:
+	case SETALL:
+		return semctl_main(ns, semid, semnum, cmd, p);
+	case SETVAL:
+		return semctl_setval(ns, semid, semnum, arg);
+	case IPC_SET:
+		if (copy_compat_semid_from_user(&semid64, p, version))
+			return -EFAULT;
+		/* fallthru */
+	case IPC_RMID:
+		return semctl_down(ns, semid, cmd, &semid64);
+	default:
+		return -EINVAL;
+	}
+}
+#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,
  * and current is THE ONE