From d1baabc8006fd238ad8da4d734dc815a8de02362 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 commit dbcea7615d8d7d58f6ff49d2c5568113f70effe9 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 [bwh: Backported to 3.2: adjust context, indentation] Signed-off-by: Ben Hutchings --- 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 180ea6c7911ce..ba6b43850a5b3 100644 --- a/drivers/usb/serial/spcp8x5.c +++ b/drivers/usb/serial/spcp8x5.c @@ -163,7 +163,6 @@ static struct usb_driver spcp8x5_driver = { struct spcp8x5_private { spinlock_t lock; enum spcp8x5_type type; - wait_queue_head_t delta_msr_wait; u8 line_control; u8 line_status; }; @@ -197,7 +196,6 @@ static int spcp8x5_startup(struct usb_serial *serial) goto cleanup; spin_lock_init(&priv->lock); - init_waitqueue_head(&priv->delta_msr_wait); priv->type = type; usb_set_serial_port_data(serial->port[i] , priv); } @@ -502,7 +500,7 @@ 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; @@ -552,12 +550,15 @@ 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); -- 2.47.3