From 664e1221e7828164acc8431968fb933ed998bbb2 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 Signed-off-by: Ben Hutchings --- 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 5532ea5f8d75..fd86e0e157ca 100644 --- a/drivers/usb/serial/pl2303.c +++ b/drivers/usb/serial/pl2303.c @@ -150,7 +150,6 @@ enum pl2303_type { struct pl2303_private { spinlock_t lock; - wait_queue_head_t delta_msr_wait; u8 line_control; u8 line_status; enum pl2303_type type; @@ -204,7 +203,6 @@ static int pl2303_startup(struct usb_serial *serial) if (!priv) 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); } @@ -599,11 +597,14 @@ 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); @@ -725,7 +726,7 @@ 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) @@ -792,7 +793,7 @@ 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; -- 2.39.2