From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757683Ab3CYBgk (ORCPT ); Sun, 24 Mar 2013 21:36:40 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:33852 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1755634Ab3CYBPW (ORCPT ); Sun, 24 Mar 2013 21:15:22 -0400 Message-Id: <20130325010533.732708594@decadent.org.uk> User-Agent: quilt/0.60-1 Date: Mon, 25 Mar 2013 01:06:59 +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: [ 095/104] USB: pl2303: 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 40509ca982c00c4b70fc00be887509feca0bff15 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/pl2303.c | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) --- a/drivers/usb/serial/pl2303.c +++ b/drivers/usb/serial/pl2303.c @@ -150,7 +150,6 @@ enum pl2303_type { struct pl2303_private { spinlock_t lock; - wait_queue_head_t delta_msr_wait; u8 line_control; u8 line_status; enum pl2303_type type; @@ -204,7 +203,6 @@ static int pl2303_startup(struct usb_ser if (!priv) goto cleanup; spin_lock_init(&priv->lock); - init_waitqueue_head(&priv->delta_msr_wait); priv->type = type; usb_set_serial_port_data(serial->port[i], priv); } @@ -599,11 +597,14 @@ static int wait_modem_info(struct usb_se spin_unlock_irqrestore(&priv->lock, flags); while (1) { - 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; spin_unlock_irqrestore(&priv->lock, flags); @@ -725,7 +726,7 @@ static void pl2303_update_line_status(st spin_unlock_irqrestore(&priv->lock, flags); if (priv->line_status & UART_BREAK_ERROR) usb_serial_handle_break(port); - wake_up_interruptible(&priv->delta_msr_wait); + wake_up_interruptible(&port->delta_msr_wait); tty = tty_port_tty_get(&port->port); if (!tty) @@ -792,7 +793,7 @@ static void pl2303_process_read_urb(stru line_status = priv->line_status; priv->line_status &= ~UART_STATE_TRANSIENT_MASK; spin_unlock_irqrestore(&priv->lock, flags); - wake_up_interruptible(&priv->delta_msr_wait); + wake_up_interruptible(&port->delta_msr_wait); if (!urb->actual_length) return;