From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1755835Ab3CYBPd (ORCPT ); Sun, 24 Mar 2013 21:15:33 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:33882 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755693Ab3CYBPZ (ORCPT ); Sun, 24 Mar 2013 21:15:25 -0400 Message-Id: <20130325010532.711405969@decadent.org.uk> User-Agent: quilt/0.60-1 Date: Mon, 25 Mar 2013 01:06:49 +0000 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org Cc: akpm@linux-foundation.org, Johan Hovold , Greg Kroah-Hartman Subject: [ 085/104] USB: ark3116: fix use-after-free in TIOCMIWAIT Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit In-Reply-To: <20130325010524.240972766@decadent.org.uk> X-SA-Exim-Connect-IP: 2001:470:1f08:1539:f137:78a:b654:affb X-SA-Exim-Mail-From: ben@decadent.org.uk X-SA-Exim-Scanned: No (on shadbolt.decadent.org.uk); SAEximRunCond expanded to false Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.2-stable review patch. If anyone has any objections, please let me know. ------------------ From: Johan Hovold 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 Signed-off-by: Greg Kroah-Hartman Signed-off-by: Ben Hutchings --- drivers/usb/serial/ark3116.c | 10 ++++++---- 1 file changed, 6 insertions(+), 4 deletions(-) --- a/drivers/usb/serial/ark3116.c +++ b/drivers/usb/serial/ark3116.c @@ -68,7 +68,6 @@ static int is_irda(struct usb_serial *se } struct ark3116_private { - wait_queue_head_t delta_msr_wait; struct async_icount icount; int irda; /* 1 for irda device */ @@ -148,7 +147,6 @@ static int ark3116_attach(struct usb_ser 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 @@ static int ark3116_ioctl(struct tty_stru 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 @@ static void ark3116_update_msr(struct us 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); } }