Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753770Ab3DVO3S (ORCPT ); Mon, 22 Apr 2013 10:29:18 -0400 Received: from shadbolt.e.decadent.org.uk ([88.96.1.126]:51369 "EHLO shadbolt.e.decadent.org.uk" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753064Ab3DVO3N (ORCPT ); Mon, 22 Apr 2013 10:29:13 -0400 Content-Type: text/plain; charset="UTF-8" Content-Disposition: inline Content-Transfer-Encoding: 8bit MIME-Version: 1.0 From: Ben Hutchings To: linux-kernel@vger.kernel.org, stable@vger.kernel.org CC: akpm@linux-foundation.org, "Greg Kroah-Hartman" , "Johan Hovold" Date: Mon, 22 Apr 2013 15:25:59 +0100 Message-ID: X-Mailer: LinuxStableQueue (scripts by bwh) Subject: [07/75] USB: io_edgeport: fix use-after-free in TIOCMIWAIT In-Reply-To: X-SA-Exim-Connect-IP: 2001:470:1f08:1539:6834:ff73:7553:7f84 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 Content-Length: 2912 Lines: 74 3.2.44-rc1 review patch. If anyone has any objections, please let me know. ------------------ From: Johan Hovold commit 333576255d4cfc53efd056aad438568184b36af6 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/io_edgeport.c | 12 +++++++----- 1 file changed, 7 insertions(+), 5 deletions(-) --- a/drivers/usb/serial/io_edgeport.c +++ b/drivers/usb/serial/io_edgeport.c @@ -114,7 +114,6 @@ struct edgeport_port { wait_queue_head_t wait_chase; /* for handling sleeping while waiting for chase to finish */ wait_queue_head_t wait_open; /* for handling sleeping while waiting for open to finish */ wait_queue_head_t wait_command; /* for handling sleeping while waiting for command to finish */ - wait_queue_head_t delta_msr_wait; /* for handling sleeping while waiting for msr change to happen */ struct async_icount icount; struct usb_serial_port *port; /* loop back to the owner of this object */ @@ -885,7 +884,6 @@ static int edge_open(struct tty_struct * /* initialize our wait queues */ init_waitqueue_head(&edge_port->wait_open); init_waitqueue_head(&edge_port->wait_chase); - init_waitqueue_head(&edge_port->delta_msr_wait); init_waitqueue_head(&edge_port->wait_command); /* initialize our icount structure */ @@ -1703,13 +1701,17 @@ static int edge_ioctl(struct tty_struct dbg("%s (%d) TIOCMIWAIT", __func__, port->number); cprev = edge_port->icount; while (1) { - prepare_to_wait(&edge_port->delta_msr_wait, + prepare_to_wait(&port->delta_msr_wait, &wait, TASK_INTERRUPTIBLE); schedule(); - finish_wait(&edge_port->delta_msr_wait, &wait); + finish_wait(&port->delta_msr_wait, &wait); /* see if a signal did it */ if (signal_pending(current)) return -ERESTARTSYS; + + if (port->serial->disconnected) + return -EIO; + cnow = edge_port->icount; if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr && cnow.dcd == cprev.dcd && cnow.cts == cprev.cts) @@ -2090,7 +2092,7 @@ static void handle_new_msr(struct edgepo icount->dcd++; if (newMsr & EDGEPORT_MSR_DELTA_RI) icount->rng++; - wake_up_interruptible(&edge_port->delta_msr_wait); + wake_up_interruptible(&edge_port->port->delta_msr_wait); } /* Save the new modem status */ -- 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/