From 0a9f03287a9290fb61aa74604b4f8fd7fdd3b64e Mon Sep 17 00:00:00 2001 From: Johan Hovold Date: Tue, 19 Mar 2013 09:21:26 +0100 Subject: [PATCH] USB: ti_usb_3410_5052: fix use-after-free in TIOCMIWAIT commit fc98ab873aa3dbe783ce56a2ffdbbe7c7609521a 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/ti_usb_3410_5052.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) diff --git a/drivers/usb/serial/ti_usb_3410_5052.c b/drivers/usb/serial/ti_usb_3410_5052.c index f2530d2ef3c4..4a8b68562651 100644 --- a/drivers/usb/serial/ti_usb_3410_5052.c +++ b/drivers/usb/serial/ti_usb_3410_5052.c @@ -74,7 +74,6 @@ struct ti_port { int tp_flags; int tp_closing_wait;/* in .01 secs */ struct async_icount tp_icount; - wait_queue_head_t tp_msr_wait; /* wait for msr change */ wait_queue_head_t tp_write_wait; struct ti_device *tp_tdev; struct usb_serial_port *tp_port; @@ -432,7 +431,6 @@ static int ti_port_probe(struct usb_serial_port *port) else tport->tp_uart_base_addr = TI_UART2_BASE_ADDR; tport->tp_closing_wait = closing_wait; - init_waitqueue_head(&tport->tp_msr_wait); init_waitqueue_head(&tport->tp_write_wait); if (kfifo_alloc(&tport->write_fifo, TI_WRITE_BUF_SIZE, GFP_KERNEL)) { kfree(tport); @@ -784,9 +782,13 @@ static int ti_ioctl(struct tty_struct *tty, dev_dbg(&port->dev, "%s - TIOCMIWAIT\n", __func__); cprev = tport->tp_icount; while (1) { - interruptible_sleep_on(&tport->tp_msr_wait); + interruptible_sleep_on(&port->delta_msr_wait); if (signal_pending(current)) return -ERESTARTSYS; + + if (port->serial->disconnected) + return -EIO; + cnow = tport->tp_icount; if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr && cnow.dcd == cprev.dcd && cnow.cts == cprev.cts) @@ -1400,7 +1402,7 @@ static void ti_handle_new_msr(struct ti_port *tport, __u8 msr) icount->dcd++; if (msr & TI_MSR_DELTA_RI) icount->rng++; - wake_up_interruptible(&tport->tp_msr_wait); + wake_up_interruptible(&tport->tp_port->delta_msr_wait); spin_unlock_irqrestore(&tport->tp_lock, flags); } -- 2.39.5