Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S935324AbaDJDXu (ORCPT ); Wed, 9 Apr 2014 23:23:50 -0400 Received: from mail.linuxfoundation.org ([140.211.169.12]:41096 "EHLO mail.linuxfoundation.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S934755AbaDJDWT (ORCPT ); Wed, 9 Apr 2014 23:22:19 -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 3.4 063/134] USB: io_ti: fix use-after-free in TIOCMIWAIT Date: Wed, 9 Apr 2014 20:22:59 -0700 Message-Id: <20140410032308.183773945@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 7b2459690584f239650a365f3411ba2ec1c6d1e0 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/io_ti.c | 12 ++++++------ 1 file changed, 6 insertions(+), 6 deletions(-) --- a/drivers/usb/serial/io_ti.c +++ b/drivers/usb/serial/io_ti.c @@ -91,9 +91,6 @@ struct edgeport_port { int close_pending; int lsr_event; struct async_icount icount; - wait_queue_head_t delta_msr_wait; /* for handling sleeping while - waiting for msr change to - happen */ struct edgeport_serial *edge_serial; struct usb_serial_port *port; __u8 bUartMode; /* Port type, 0: RS232, etc. */ @@ -1549,7 +1546,7 @@ static void handle_new_msr(struct edgepo icount->dcd++; if (msr & 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 */ @@ -1867,7 +1864,6 @@ static int edge_open(struct tty_struct * dev = port->serial->dev; memset(&(edge_port->icount), 0x00, sizeof(edge_port->icount)); - init_waitqueue_head(&edge_port->delta_msr_wait); /* turn off loopback */ status = ti_do_config(edge_port, UMPC_SET_CLR_LOOPBACK, 0); @@ -2553,10 +2549,14 @@ static int edge_ioctl(struct tty_struct dbg("%s - (%d) TIOCMIWAIT", __func__, port->number); cprev = edge_port->icount; while (1) { - interruptible_sleep_on(&edge_port->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; + cnow = edge_port->icount; if (cnow.rng == cprev.rng && cnow.dsr == cprev.dsr && cnow.dcd == cprev.dcd && cnow.cts == cprev.cts) -- 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/