USB: ark3116: fix use-after-free in TIOCMIWAIT
commit 5018860321dc7a9e50a75d5f319bc981298fb5b7 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 <jhovold@gmail.com>
Signed-off-by: Ben Hutchings <ben@decadent.org.uk>
Cc: Yang Yingliang <yangyingliang@huawei.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
diff --git a/drivers/usb/serial/ark3116.c b/drivers/usb/serial/ark3116.c
index 31bfe60..9282703 100644
--- a/drivers/usb/serial/ark3116.c
+++ b/drivers/usb/serial/ark3116.c
@@ -68,7 +68,6 @@
}
struct ark3116_private {
- wait_queue_head_t delta_msr_wait;
struct async_icount icount;
int irda; /* 1 for irda device */
@@ -148,7 +147,6 @@
if (!priv)
return -ENOMEM;
- init_waitqueue_head(&priv->delta_msr_wait);
mutex_init(&priv->hw_lock);
spin_lock_init(&priv->status_lock);
@@ -460,10 +458,14 @@
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) &&
@@ -584,7 +586,7 @@
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);
}
}