Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1760172Ab2FGIbx (ORCPT ); Thu, 7 Jun 2012 04:31:53 -0400 Received: from www84.your-server.de ([213.133.104.84]:40739 "EHLO www84.your-server.de" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1760016Ab2FGIbt (ORCPT ); Thu, 7 Jun 2012 04:31:49 -0400 From: stefani@seibold.net To: linux-kernel@vger.kernel.org, gregkh@linuxfoundation.org, oneukum@suse.de Cc: linux-usb@vger.kernel.org, Stefani Seibold Subject: [PATCH 10/13] fix race in skel_write Date: Thu, 7 Jun 2012 10:20:40 +0200 Message-Id: <1339057243-10029-11-git-send-email-stefani@seibold.net> X-Mailer: git-send-email 1.7.8.6 In-Reply-To: <1339057243-10029-1-git-send-email-stefani@seibold.net> References: <1339057243-10029-1-git-send-email-stefani@seibold.net> X-Authenticated-Sender: stefani@seibold.net Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 1668 Lines: 48 From: Stefani Seibold Access to members of dev->interface without holding the io_mutex lock could result in a NULL pointer access, since disconnect will do this as a marker for disconnect. Signed-off-by: Stefani Seibold --- drivers/usb/usb-skeleton.c | 5 +++-- 1 files changed, 3 insertions(+), 2 deletions(-) diff --git a/drivers/usb/usb-skeleton.c b/drivers/usb/usb-skeleton.c index 6482acb..0a1ab0b 100644 --- a/drivers/usb/usb-skeleton.c +++ b/drivers/usb/usb-skeleton.c @@ -96,7 +96,7 @@ static int skel_open(struct inode *inode, struct file *file) kref_get(&dev->kref); /* - * must be not locked since disconnect waits in usb_deregister_dev() + * must be not locked since a disconnect waits in usb_deregister_dev() * due the already locked minor_rwsem in the usb_open() function */ retval = usb_autopm_get_interface(interface); @@ -441,13 +441,14 @@ static ssize_t skel_write(struct file *file, const char *user_buffer, /* send the data out the bulk port */ retval = usb_submit_urb(urb, GFP_KERNEL); - mutex_unlock(&dev->io_mutex); if (retval) { dev_err(&dev->interface->dev, "%s - failed submitting write urb, error %d\n", __func__, retval); + mutex_unlock(&dev->io_mutex); goto error_unanchor; } + mutex_unlock(&dev->io_mutex); /* * release our reference to this urb, the USB core will eventually free -- 1.7.8.6 -- 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/