From 8edfdab37157d2683e51b8be5d3d5697f66a9f7b Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Tue, 19 Mar 2013 09:21:21 +0100 Subject: [PATCH] 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 Signed-off-by: Johan Hovold Signed-off-by: Greg Kroah-Hartman --- drivers/usb/serial/oti6858.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/drivers/usb/serial/oti6858.c b/drivers/usb/serial/oti6858.c index a958fd41b5b..87c71ccfee8 100644 --- a/drivers/usb/serial/oti6858.c +++ b/drivers/usb/serial/oti6858.c @@ -188,7 +188,6 @@ struct oti6858_private { 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 @@ static int oti6858_port_probe(struct usb_serial_port *port) 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 @@ static int wait_modem_info(struct usb_serial_port *port, unsigned int arg) 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 @@ static void oti6858_read_int_callback(struct urb *urb) 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); } -- 2.41.0