osf_wait4(): fix infoleak

BugLink: http://bugs.launchpad.net/bugs/1694621

commit a8c39544 upstream.

failing sys_wait4() won't fill struct rusage...
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Signed-off-by: Stefan Bader <stefan.bader@canonical.com>
Signed-off-by: Thadeu Lima de Souza Cascardo <cascardo@canonical.com>

arch/alpha/kernel/osf_sys.c

@@ -1188,8 +1188,10 @@ SYSCALL_DEFINE4(osf_wait4, pid_t, pid, int __user *, ustatus, int, options,
 	if (!access_ok(VERIFY_WRITE, ur, sizeof(*ur)))
 		return -EFAULT;
 
-	err = 0;
-	err |= put_user(status, ustatus);
+	err = put_user(status, ustatus);
+	if (ret < 0)
+		return err ? err : ret;
+
 	err |= __put_user(r.ru_utime.tv_sec, &ur->ru_utime.tv_sec);
 	err |= __put_user(r.ru_utime.tv_usec, &ur->ru_utime.tv_usec);
 	err |= __put_user(r.ru_stime.tv_sec, &ur->ru_stime.tv_sec);