diff --git a/drivers/tty/tty_io.c b/drivers/tty/tty_io.c index 0c41dbcb90b8bc7d8ab430d562206e7c2469411f..bcc8e1e8bb720996cf73438c67a397362173edca 100644 --- a/drivers/tty/tty_io.c +++ b/drivers/tty/tty_io.c @@ -1282,18 +1282,22 @@ int tty_send_xchar(struct tty_struct *tty, char ch) int was_stopped = tty->stopped; if (tty->ops->send_xchar) { + down_read(&tty->termios_rwsem); tty->ops->send_xchar(tty, ch); + up_read(&tty->termios_rwsem); return 0; } if (tty_write_lock(tty, 0) < 0) return -ERESTARTSYS; + down_read(&tty->termios_rwsem); if (was_stopped) start_tty(tty); tty->ops->write(tty, &ch, 1); if (was_stopped) stop_tty(tty); + up_read(&tty->termios_rwsem); tty_write_unlock(tty); return 0; } diff --git a/drivers/tty/tty_ioctl.c b/drivers/tty/tty_ioctl.c index 9c5aebfe7053cbcae1fd65a95f3312509525e8e6..1445dd39aa6227ab641130ef7344eaba9f113b86 100644 --- a/drivers/tty/tty_ioctl.c +++ b/drivers/tty/tty_ioctl.c @@ -1147,16 +1147,12 @@ int n_tty_ioctl_helper(struct tty_struct *tty, struct file *file, spin_unlock_irq(&tty->flow_lock); break; case TCIOFF: - down_read(&tty->termios_rwsem); if (STOP_CHAR(tty) != __DISABLED_CHAR) retval = tty_send_xchar(tty, STOP_CHAR(tty)); - up_read(&tty->termios_rwsem); break; case TCION: - down_read(&tty->termios_rwsem); if (START_CHAR(tty) != __DISABLED_CHAR) retval = tty_send_xchar(tty, START_CHAR(tty)); - up_read(&tty->termios_rwsem); break; default: return -EINVAL;