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

    USB: ark3116: 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 5018860321dc7a9e50a75d5f319bc981298fb5b7 Mon Sep 17 00:00:00 2001
From: Johan Hovold <[email protected]>
Date: Tue, 19 Mar 2013 09:21:11 +0100
Subject: USB: ark3116: 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 <[email protected]>
Signed-off-by: Johan Hovold <[email protected]>
Signed-off-by: Greg Kroah-Hartman <[email protected]>
---
 drivers/usb/serial/ark3116.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/usb/serial/ark3116.c b/drivers/usb/serial/ark3116.c
index cbd904b..4775f82 100644
--- a/drivers/usb/serial/ark3116.c
+++ b/drivers/usb/serial/ark3116.c
@@ -62,7 +62,6 @@ static int is_irda(struct usb_serial *serial)
 }
 
 struct ark3116_private {
-       wait_queue_head_t       delta_msr_wait;
        struct async_icount     icount;
        int                     irda;   /* 1 for irda device */
 
@@ -146,7 +145,6 @@ static int ark3116_port_probe(struct usb_serial_port *port)
        if (!priv)
                return -ENOMEM;
 
-       init_waitqueue_head(&priv->delta_msr_wait);
        mutex_init(&priv->hw_lock);
        spin_lock_init(&priv->status_lock);
 
@@ -456,10 +454,14 @@ static int ark3116_ioctl(struct tty_struct *tty,
        case TIOCMIWAIT:
                for (;;) {
                        struct async_icount prev = priv->icount;
-                       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;
+
                        if ((prev.rng == priv->icount.rng) &&
                            (prev.dsr == priv->icount.dsr) &&
                            (prev.dcd == priv->icount.dcd) &&
@@ -580,7 +582,7 @@ static void ark3116_update_msr(struct usb_serial_port 
*port, __u8 msr)
                        priv->icount.dcd++;
                if (msr & UART_MSR_TERI)
                        priv->icount.rng++;
-               wake_up_interruptible(&priv->delta_msr_wait);
+               wake_up_interruptible(&port->delta_msr_wait);
        }
 }
 
-- 
1.8.0.rc0.18.gf84667d


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