Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S965056Ab3DHKNG (ORCPT ); Mon, 8 Apr 2013 06:13:06 -0400 Received: from youngberry.canonical.com ([91.189.89.112]:42799 "EHLO youngberry.canonical.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S935673Ab3DHJv4 (ORCPT ); Mon, 8 Apr 2013 05:51:56 -0400 From: Luis Henriques To: linux-kernel@vger.kernel.org, stable@vger.kernel.org, kernel-team@lists.ubuntu.com Cc: Johan Hovold , Greg Kroah-Hartman , Luis Henriques Subject: [PATCH 045/102] USB: mos7840: fix use-after-free in TIOCMIWAIT Date: Mon, 8 Apr 2013 10:50:00 +0100 Message-Id: <1365414657-29191-46-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 Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 2854 Lines: 79 3.5.7.10 -stable review patch. If anyone has any objections, please let me know. ------------------ From: Johan Hovold commit a14430db686b8e459e1cf070a6ecf391515c9ab9 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: Luis Henriques --- drivers/usb/serial/mos7840.c | 13 ++++++++----- 1 file changed, 8 insertions(+), 5 deletions(-) diff --git a/drivers/usb/serial/mos7840.c b/drivers/usb/serial/mos7840.c index be5f09b..2727955 100644 --- a/drivers/usb/serial/mos7840.c +++ b/drivers/usb/serial/mos7840.c @@ -224,7 +224,6 @@ struct moschip_port { char open; char open_ports; wait_queue_head_t wait_chase; /* for handling sleeping while waiting for chase to finish */ - wait_queue_head_t delta_msr_wait; /* for handling sleeping while waiting for msr change to happen */ int delta_msr_cond; struct async_icount icount; struct usb_serial_port *port; /* loop back to the owner of this object */ @@ -444,7 +443,7 @@ static void mos7840_handle_new_msr(struct moschip_port *port, __u8 new_msr) } mos7840_port->delta_msr_cond = 1; - wake_up_interruptible(&mos7840_port->delta_msr_wait); + wake_up_interruptible(&port->port->delta_msr_wait); } } @@ -1166,7 +1165,6 @@ static int mos7840_open(struct tty_struct *tty, struct usb_serial_port *port) /* initialize our wait queues */ init_waitqueue_head(&mos7840_port->wait_chase); - init_waitqueue_head(&mos7840_port->delta_msr_wait); /* initialize our icount structure */ memset(&(mos7840_port->icount), 0x00, sizeof(mos7840_port->icount)); @@ -2307,13 +2305,18 @@ static int mos7840_ioctl(struct tty_struct *tty, while (1) { /* interruptible_sleep_on(&mos7840_port->delta_msr_wait); */ mos7840_port->delta_msr_cond = 0; - wait_event_interruptible(mos7840_port->delta_msr_wait, - (mos7840_port-> + wait_event_interruptible(port->delta_msr_wait, + (port->serial->disconnected || + mos7840_port-> delta_msr_cond == 1)); /* see if a signal did it */ if (signal_pending(current)) return -ERESTARTSYS; + + if (port->serial->disconnected) + return -EIO; + cnow = mos7840_port->icount; smp_rmb(); if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr && -- 1.8.1.2 -- 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/