This is a note to let you know that I've just added the patch titled

    USB: spcp8x5: fix use-after-free in TIOCMIWAIT

to my usb git tree which can be found at
    git://git.kernel.org/pub/scm/linux/kernel/git/gregkh/usb.git
in the usb-linus branch.

The patch will show up in the next release of the linux-next tree
(usually sometime within the next 24 hours during the week.)

The patch will hopefully also be merged in Linus's tree for the
next -rc kernel release.

If you have any questions about this process, please let me know.


>From dbcea7615d8d7d58f6ff49d2c5568113f70effe9 Mon Sep 17 00:00:00 2001
From: Johan Hovold <jhov...@gmail.com>
Date: Tue, 19 Mar 2013 09:21:24 +0100
Subject: 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 <stable@vger.kernel.org>
Signed-off-by: Johan Hovold <jhov...@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
 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 91ff8e3..549ef68 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);
-- 
1.8.0.rc0.18.gf84667d


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