USB: oti6858: fix use-after-free in TIOCMIWAIT
Use the port wait queue and make sure to check the serial disconnected
flag before accessing private port data after waking up.
This is is needed as the private port data (including the wait queue
itself) can be gone when waking up after a disconnect.
Cc: stable <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <jhovold@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/usb/serial/oti6858.c b/drivers/usb/serial/oti6858.c
index a958fd4..87c71cc 100644
--- a/drivers/usb/serial/oti6858.c
+++ b/drivers/usb/serial/oti6858.c
@@ -188,7 +188,6 @@
u8 setup_done;
struct delayed_work delayed_setup_work;
- wait_queue_head_t intr_wait;
struct usb_serial_port *port; /* USB port with which associated */
};
@@ -339,7 +338,6 @@
return -ENOMEM;
spin_lock_init(&priv->lock);
- init_waitqueue_head(&priv->intr_wait);
priv->port = port;
INIT_DELAYED_WORK(&priv->delayed_setup_work, setup_line);
INIT_DELAYED_WORK(&priv->delayed_write_work, send_data);
@@ -664,11 +662,15 @@
spin_unlock_irqrestore(&priv->lock, flags);
while (1) {
- wait_event_interruptible(priv->intr_wait,
+ wait_event_interruptible(port->delta_msr_wait,
+ port->serial->disconnected ||
priv->status.pin_state != prev);
if (signal_pending(current))
return -ERESTARTSYS;
+ if (port->serial->disconnected)
+ return -EIO;
+
spin_lock_irqsave(&priv->lock, flags);
status = priv->status.pin_state & PIN_MASK;
spin_unlock_irqrestore(&priv->lock, flags);
@@ -763,7 +765,7 @@
if (!priv->transient) {
if (xs->pin_state != priv->status.pin_state)
- wake_up_interruptible(&priv->intr_wait);
+ wake_up_interruptible(&port->delta_msr_wait);
memcpy(&priv->status, xs, OTI6858_CTRL_PKT_SIZE);
}
