From 281e3d62958d6f53cc1b40b8949374ab0030a9af Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Tue, 19 Mar 2013 09:21:22 +0100 Subject: [PATCH] USB: pl2303: fix use-after-free in TIOCMIWAIT commit 40509ca982c00c4b70fc00be887509feca0bff15 upstream. 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. Signed-off-by: Johan Hovold Signed-off-by: Greg Kroah-Hartman --- drivers/usb/serial/pl2303.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) diff --git a/drivers/usb/serial/pl2303.c b/drivers/usb/serial/pl2303.c index 600241901361..bb056a14a90f 100644 --- a/drivers/usb/serial/pl2303.c +++ b/drivers/usb/serial/pl2303.c @@ -139,7 +139,6 @@ struct pl2303_serial_private { struct pl2303_private { spinlock_t lock; - wait_queue_head_t delta_msr_wait; u8 line_control; u8 line_status; }; @@ -233,7 +232,6 @@ static int pl2303_port_probe(struct usb_serial_port *port) return -ENOMEM; spin_lock_init(&priv->lock); - init_waitqueue_head(&priv->delta_msr_wait); usb_set_serial_port_data(port, priv); @@ -607,11 +605,14 @@ static int wait_modem_info(struct usb_serial_port *port, unsigned int arg) spin_unlock_irqrestore(&priv->lock, flags); while (1) { - 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); @@ -719,7 +720,7 @@ static void pl2303_update_line_status(struct usb_serial_port *port, spin_unlock_irqrestore(&priv->lock, flags); if (priv->line_status & UART_BREAK_ERROR) usb_serial_handle_break(port); - wake_up_interruptible(&priv->delta_msr_wait); + wake_up_interruptible(&port->delta_msr_wait); tty = tty_port_tty_get(&port->port); if (!tty) @@ -784,7 +785,7 @@ static void pl2303_process_read_urb(struct urb *urb) line_status = priv->line_status; priv->line_status &= ~UART_STATE_TRANSIENT_MASK; spin_unlock_irqrestore(&priv->lock, flags); - wake_up_interruptible(&priv->delta_msr_wait); + wake_up_interruptible(&port->delta_msr_wait); if (!urb->actual_length) return; -- 2.39.5