Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S934064Ab1FWRvP (ORCPT ); Thu, 23 Jun 2011 13:51:15 -0400 Received: from mail.windriver.com ([147.11.1.11]:35415 "EHLO mail.windriver.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S933649Ab1FWRiQ (ORCPT ); Thu, 23 Jun 2011 13:38:16 -0400 From: Paul Gortmaker To: stable@kernel.org, linux-kernel@vger.kernel.org Cc: stable-review@kernel.org, Johan Hovold , Greg Kroah-Hartman , Paul Gortmaker Subject: [34-longterm 211/247] USB: cdc-acm: fix potential null-pointer dereference on disconnect Date: Thu, 23 Jun 2011 13:34:39 -0400 Message-Id: <1308850515-15242-152-git-send-email-paul.gortmaker@windriver.com> X-Mailer: git-send-email 1.7.4.4 In-Reply-To: <1308850515-15242-1-git-send-email-paul.gortmaker@windriver.com> References: <1308849690-14530-1-git-send-email-paul.gortmaker@windriver.com> <1308850515-15242-1-git-send-email-paul.gortmaker@windriver.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1768 Lines: 52 From: Johan Hovold ------------------- This is a commit scheduled for the next v2.6.34 longterm release. If you see a problem with using this for longterm, please comment. ------------------- 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 Signed-off-by: Paul Gortmaker --- drivers/usb/class/cdc-acm.c | 3 ++- 1 files changed, 2 insertions(+), 1 deletions(-) diff --git a/drivers/usb/class/cdc-acm.c b/drivers/usb/class/cdc-acm.c index a45e6c4..073a9ef 100644 --- 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 " -- 1.7.4.4 -- 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/