Coverity reports (as CID 1536978) that uart_poll_init() passes uninitialized pm_state to uart_change_pm(). It is in case the first 'if' takes the true branch (does "goto out;"). Fix this and simplify the function by simple guard(mutex). The code needs no labels after this at all. And it is pretty clear that the code has not fiddled with pm_state at that point. Signed-off-by: Jiri Slaby (SUSE) <jirislaby@xxxxxxxxxx> Fixes: 5e227ef2aa38 (serial: uart_poll_init() should power on the UART) Cc: stable@xxxxxxxxxxxxxxx Cc: Douglas Anderson <dianders@xxxxxxxxxxxx> Cc: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> Reviewed-by: Ilpo Järvinen <ilpo.jarvinen@xxxxxxxxxxxxxxx> Reviewed-by: Douglas Anderson <dianders@xxxxxxxxxxxx> Link: https://lore.kernel.org/r/20240805102046.307511-4-jirislaby@xxxxxxxxxx Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> diff --git a/drivers/tty/serial/serial_core.c b/drivers/tty/serial/serial_core.c index 83c5bccc5086..e0aac155dca2 100644 --- a/drivers/tty/serial/serial_core.c +++ b/drivers/tty/serial/serial_core.c @@ -2690,14 +2690,13 @@ static int uart_poll_init(struct tty_driver *driver, int line, char *options) int ret = 0; tport = &state->port; - mutex_lock(&tport->mutex); + + guard(mutex)(&tport->mutex); port = uart_port_check(state); if (!port || port->type == PORT_UNKNOWN || - !(port->ops->poll_get_char && port->ops->poll_put_char)) { - ret = -1; - goto out; - } + !(port->ops->poll_get_char && port->ops->poll_put_char)) + return -1; pm_state = state->pm_state; uart_change_pm(state, UART_PM_STATE_ON); @@ -2717,10 +2716,10 @@ static int uart_poll_init(struct tty_driver *driver, int line, char *options) ret = uart_set_options(port, NULL, baud, parity, bits, flow); console_list_unlock(); } -out: + if (ret) uart_change_pm(state, pm_state); - mutex_unlock(&tport->mutex); + return ret; }
