From patchwork Mon Apr 8 09:50:03 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Luis Henriques X-Patchwork-Id: 234668 Return-Path: X-Original-To: incoming@patchwork.ozlabs.org Delivered-To: patchwork-incoming@bilbo.ozlabs.org Received: from huckleberry.canonical.com (huckleberry.canonical.com [91.189.94.19]) by ozlabs.org (Postfix) with ESMTP id CBD752C00DC for ; Mon, 8 Apr 2013 19:52:07 +1000 (EST) Received: from localhost ([127.0.0.1] helo=huckleberry.canonical.com) by huckleberry.canonical.com with esmtp (Exim 4.76) (envelope-from ) id 1UP8k5-0005cz-W9; Mon, 08 Apr 2013 09:52:01 +0000 Received: from youngberry.canonical.com ([91.189.89.112]) by huckleberry.canonical.com with esmtp (Exim 4.76) (envelope-from ) id 1UP8k2-0005UN-2g for kernel-team@lists.ubuntu.com; Mon, 08 Apr 2013 09:51:58 +0000 Received: from bl15-144-85.dsl.telepac.pt ([188.80.144.85] helo=localhost) by youngberry.canonical.com with esmtpsa (TLS1.0:DHE_RSA_AES_128_CBC_SHA1:16) (Exim 4.71) (envelope-from ) id 1UP8k1-0005zI-RI; Mon, 08 Apr 2013 09:51:58 +0000 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Subject: [PATCH 048/102] USB: quatech2: fix use-after-free in TIOCMIWAIT Date: Mon, 8 Apr 2013 10:50:03 +0100 Message-Id: <1365414657-29191-49-git-send-email-luis.henriques@canonical.com> X-Mailer: git-send-email 1.8.1.2 In-Reply-To: <1365414657-29191-1-git-send-email-luis.henriques@canonical.com> References: <1365414657-29191-1-git-send-email-luis.henriques@canonical.com> X-Extended-Stable: 3.5 Cc: Greg Kroah-Hartman , Johan Hovold X-BeenThere: kernel-team@lists.ubuntu.com X-Mailman-Version: 2.1.14 Precedence: list List-Id: Kernel team discussions List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , MIME-Version: 1.0 Errors-To: kernel-team-bounces@lists.ubuntu.com Sender: kernel-team-bounces@lists.ubuntu.com 3.5.7.10 -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 [ luis: backported to 3.5; adjust context ] Signed-off-by: Luis Henriques --- drivers/usb/serial/quatech2.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) diff --git a/drivers/usb/serial/quatech2.c b/drivers/usb/serial/quatech2.c index e1065f8..1c2c0ba 100644 --- a/drivers/usb/serial/quatech2.c +++ b/drivers/usb/serial/quatech2.c @@ -132,7 +132,6 @@ 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; @@ -528,8 +527,9 @@ static int wait_modem_info(struct usb_serial_port *port, unsigned int arg) 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))); @@ -537,6 +537,9 @@ static int wait_modem_info(struct usb_serial_port *port, unsigned int arg) 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); @@ -881,7 +884,6 @@ static int qt2_attach(struct usb_serial *serial) spin_lock_init(&port_priv->lock); spin_lock_init(&port_priv->urb_lock); - init_waitqueue_head(&port_priv->delta_msr_wait); port_priv->port = serial->port[pcount]; @@ -1015,7 +1017,7 @@ static void qt2_update_msr(struct usb_serial_port *port, unsigned char *ch) if (newMSR & UART_MSR_TERI) port_priv->icount.rng++; - wake_up_interruptible(&port_priv->delta_msr_wait); + wake_up_interruptible(&port->delta_msr_wait); } }