Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1759983Ab3DBXIT (ORCPT ); Tue, 2 Apr 2013 19:08:19 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:33030 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933226Ab3DBWMc (ORCPT ); Tue, 2 Apr 2013 18:12:32 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Johan Hovold Subject: [ 061/124] USB: quatech2: fix use-after-free in TIOCMIWAIT Date: Tue, 2 Apr 2013 15:10:43 -0700 Message-Id: <20130402221111.266512673@linuxfoundation.org> X-Mailer: git-send-email 1.8.1.rc1.5.g7e0651a In-Reply-To: <20130402221104.163133110@linuxfoundation.org> References: <20130402221104.163133110@linuxfoundation.org> User-Agent: quilt/0.60-5.1.1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2477 Lines: 77 3.8-stable review patch. If anyone has any objections, please let me know. ------------------ From: Johan Hovold commit 69f87f40d2b98e8b4ab82a121fd2bd584690b887 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/quatech2.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) --- a/drivers/usb/serial/quatech2.c +++ b/drivers/usb/serial/quatech2.c @@ -128,7 +128,6 @@ struct qt2_port_private { u8 shadowLSR; u8 shadowMSR; - wait_queue_head_t delta_msr_wait; /* Used for TIOCMIWAIT */ struct async_icount icount; struct usb_serial_port *port; @@ -506,8 +505,9 @@ static int wait_modem_info(struct usb_se spin_unlock_irqrestore(&priv->lock, flags); while (1) { - wait_event_interruptible(priv->delta_msr_wait, - ((priv->icount.rng != prev.rng) || + wait_event_interruptible(port->delta_msr_wait, + (port->serial->disconnected || + (priv->icount.rng != prev.rng) || (priv->icount.dsr != prev.dsr) || (priv->icount.dcd != prev.dcd) || (priv->icount.cts != prev.cts))); @@ -515,6 +515,9 @@ static int wait_modem_info(struct usb_se if (signal_pending(current)) return -ERESTARTSYS; + if (port->serial->disconnected) + return -EIO; + spin_lock_irqsave(&priv->lock, flags); cur = priv->icount; spin_unlock_irqrestore(&priv->lock, flags); @@ -841,7 +844,6 @@ static int qt2_port_probe(struct usb_ser spin_lock_init(&port_priv->lock); spin_lock_init(&port_priv->urb_lock); - init_waitqueue_head(&port_priv->delta_msr_wait); port_priv->port = port; port_priv->write_urb = usb_alloc_urb(0, GFP_KERNEL); @@ -984,7 +986,7 @@ static void qt2_update_msr(struct usb_se if (newMSR & UART_MSR_TERI) port_priv->icount.rng++; - wake_up_interruptible(&port_priv->delta_msr_wait); + wake_up_interruptible(&port->delta_msr_wait); } } -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/