[PATCH 6.11 596/695] serial: dont use uninitialized value in uart_poll_init()

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



6.11-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Jiri Slaby (SUSE) <jirislaby@xxxxxxxxxx>

commit d0009a32c9e4e083358092f3c97e3c6e803a8930 upstream.

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>
---
 drivers/tty/serial/serial_core.c |   13 ++++++-------
 1 file changed, 6 insertions(+), 7 deletions(-)

--- a/drivers/tty/serial/serial_core.c
+++ b/drivers/tty/serial/serial_core.c
@@ -2696,14 +2696,13 @@ static int uart_poll_init(struct tty_dri
 	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);
@@ -2723,10 +2722,10 @@ static int uart_poll_init(struct tty_dri
 		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;
 }
 






[Index of Archives]     [Linux Kernel]     [Kernel Development Newbies]     [Linux USB Devel]     [Video for Linux]     [Linux Audio Users]     [Yosemite Hiking]     [Linux Kernel]     [Linux SCSI]

  Powered by Linux