From dbcea7615d8d7d58f6ff49d2c5568113f70effe9 Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Tue, 19 Mar 2013 09:21:24 +0100 Subject: [PATCH] USB: spcp8x5: 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/spcp8x5.c | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/drivers/usb/serial/spcp8x5.c b/drivers/usb/serial/spcp8x5.c index 91ff8e3bddb..549ef68ff5f 100644 --- a/drivers/usb/serial/spcp8x5.c +++ b/drivers/usb/serial/spcp8x5.c @@ -149,7 +149,6 @@ enum spcp8x5_type { struct spcp8x5_private { spinlock_t lock; enum spcp8x5_type type; - wait_queue_head_t delta_msr_wait; u8 line_control; u8 line_status; }; @@ -179,7 +178,6 @@ static int spcp8x5_port_probe(struct usb_serial_port *port) return -ENOMEM; spin_lock_init(&priv->lock); - init_waitqueue_head(&priv->delta_msr_wait); priv->type = type; usb_set_serial_port_data(port , priv); @@ -475,7 +473,7 @@ static void spcp8x5_process_read_urb(struct urb *urb) priv->line_status &= ~UART_STATE_TRANSIENT_MASK; spin_unlock_irqrestore(&priv->lock, flags); /* wake up the wait for termios */ - wake_up_interruptible(&priv->delta_msr_wait); + wake_up_interruptible(&port->delta_msr_wait); if (!urb->actual_length) return; @@ -526,12 +524,15 @@ static int spcp8x5_wait_modem_info(struct usb_serial_port *port, while (1) { /* wake up in bulk read */ - interruptible_sleep_on(&priv->delta_msr_wait); + interruptible_sleep_on(&port->delta_msr_wait); /* see if a signal did it */ if (signal_pending(current)) return -ERESTARTSYS; + if (port->serial->disconnected) + return -EIO; + spin_lock_irqsave(&priv->lock, flags); status = priv->line_status; spin_unlock_irqrestore(&priv->lock, flags); -- 2.41.0