Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934912AbaDJEMR (ORCPT ); Thu, 10 Apr 2014 00:12:17 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:41084 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934736AbaDJDWQ (ORCPT ); Wed, 9 Apr 2014 23:22:16 -0400 From: Greg Kroah-Hartman To: linux-kernel@vger.kernel.org Cc: Greg Kroah-Hartman , stable@vger.kernel.org, Johan Hovold , Ben Hutchings , Yang Yingliang Subject: [PATCH 3.4 059/134] USB: ch341: fix use-after-free in TIOCMIWAIT Date: Wed, 9 Apr 2014 20:22:55 -0700 Message-Id: <20140410032307.631074605@linuxfoundation.org> X-Mailer: git-send-email 1.9.0 In-Reply-To: <20140410032259.587501440@linuxfoundation.org> References: <20140410032259.587501440@linuxfoundation.org> User-Agent: quilt/0.60-1 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 3.4-stable review patch. If anyone has any objections, please let me know. ------------------ From: Johan Hovold commit fa1e11d5231c001c80a479160b5832933c5d35fb 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: Ben Hutchings Cc: Yang Yingliang Signed-off-by: Greg Kroah-Hartman --- drivers/usb/serial/ch341.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) --- a/drivers/usb/serial/ch341.c +++ b/drivers/usb/serial/ch341.c @@ -82,7 +82,6 @@ MODULE_DEVICE_TABLE(usb, id_table); struct ch341_private { spinlock_t lock; /* access lock */ - wait_queue_head_t delta_msr_wait; /* wait queue for modem status */ unsigned baud_rate; /* set baud rate */ u8 line_control; /* set line control value RTS/DTR */ u8 line_status; /* active status of modem control inputs */ @@ -262,7 +261,6 @@ static int ch341_attach(struct usb_seria return -ENOMEM; spin_lock_init(&priv->lock); - init_waitqueue_head(&priv->delta_msr_wait); priv->baud_rate = DEFAULT_BAUD_RATE; priv->line_control = CH341_BIT_RTS | CH341_BIT_DTR; @@ -299,7 +297,7 @@ static void ch341_dtr_rts(struct usb_ser priv->line_control &= ~(CH341_BIT_RTS | CH341_BIT_DTR); spin_unlock_irqrestore(&priv->lock, flags); ch341_set_handshake(port->serial->dev, priv->line_control); - wake_up_interruptible(&priv->delta_msr_wait); + wake_up_interruptible(&port->delta_msr_wait); } static void ch341_close(struct usb_serial_port *port) @@ -502,7 +500,7 @@ static void ch341_read_int_callback(stru tty_kref_put(tty); } - wake_up_interruptible(&priv->delta_msr_wait); + wake_up_interruptible(&port->delta_msr_wait); } exit: @@ -528,11 +526,14 @@ static int wait_modem_info(struct usb_se spin_unlock_irqrestore(&priv->lock, flags); while (!multi_change) { - 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; + spin_lock_irqsave(&priv->lock, flags); status = priv->line_status; multi_change = priv->multi_status_change; -- 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/