From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S932902Ab1CZAF7 (ORCPT ); Fri, 25 Mar 2011 20:05:59 -0400 Received: from kroah.org ([198.145.64.141]:41888 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932563Ab1CYXxA (ORCPT ); Fri, 25 Mar 2011 19:53:00 -0400 X-Mailbox-Line: From gregkh@clark.kroah.org Fri Mar 25 16:45:12 2011 Message-Id: <20110325234512.871361953@clark.kroah.org> User-Agent: quilt/0.48-16.4 Date: Fri, 25 Mar 2011 16:44:24 -0700 From: Greg KH To: linux-kernel@vger.kernel.org, stable@kernel.org Cc: stable-review@kernel.org, torvalds@linux-foundation.org, akpm@linux-foundation.org, alan@lxorguk.ukuu.org.uk, Johan Hovold Subject: [48/63] USB: cdc-acm: fix potential null-pointer dereference on disconnect In-Reply-To: <20110325234526.GA18017@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.38-stable review patch. If anyone has any objections, please let us know. ------------------ From: Johan Hovold commit 7e7797e7f6f7bfab73fca02c65e40eaa5bb9000c upstream. Fix potential null-pointer exception on disconnect introduced by commit 11ea859d64b69a747d6b060b9ed1520eab1161fe (USB: additional power savings for cdc-acm devices that support remote wakeup). Only access acm->dev after making sure it is non-null in control urb completion handler. Signed-off-by: Johan Hovold Signed-off-by: Greg Kroah-Hartman --- drivers/usb/class/cdc-acm.c | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) --- a/drivers/usb/class/cdc-acm.c +++ b/drivers/usb/class/cdc-acm.c @@ -297,6 +297,8 @@ static void acm_ctrl_irq(struct urb *urb if (!ACM_READY(acm)) goto exit; + usb_mark_last_busy(acm->dev); + data = (unsigned char *)(dr + 1); switch (dr->bNotificationType) { case USB_CDC_NOTIFY_NETWORK_CONNECTION: @@ -336,7 +338,6 @@ static void acm_ctrl_irq(struct urb *urb break; } exit: - usb_mark_last_busy(acm->dev); retval = usb_submit_urb(urb, GFP_ATOMIC); if (retval) dev_err(&urb->dev->dev, "%s - usb_submit_urb failed with "