For serdev framework, tty->dev is a NULL pointer, lpuart_uport_is_active calling device_may_wakeup() may cause kernel NULL pointer crash, so here add the NULL pointer check before using it. Fixes: 4f5cb8c5e915 ("tty: serial: fsl_lpuart: enable wakeup source for lpuart") Signed-off-by: Sherry Sun <sherry.sun@xxxxxxx> --- drivers/tty/serial/fsl_lpuart.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/tty/serial/fsl_lpuart.c b/drivers/tty/serial/fsl_lpuart.c index 3281e81e1723..8daac87d063c 100644 --- a/drivers/tty/serial/fsl_lpuart.c +++ b/drivers/tty/serial/fsl_lpuart.c @@ -3022,7 +3022,7 @@ static bool lpuart_uport_is_active(struct lpuart_port *sport) tty = tty_port_tty_get(port); if (tty) { tty_dev = tty->dev; - may_wake = device_may_wakeup(tty_dev); + may_wake = tty_dev && device_may_wakeup(tty_dev); tty_kref_put(tty); } -- 2.17.1