From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1756754Ab0CaAWw (ORCPT ); Tue, 30 Mar 2010 20:22:52 -0400 Received: from kroah.org ([198.145.64.141]:49095 "EHLO coco.kroah.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1756570Ab0C3XMm (ORCPT ); Tue, 30 Mar 2010 19:12:42 -0400 X-Mailbox-Line: From linux@linux.site Tue Mar 30 15:58:43 2010 Message-Id: <20100330225842.638011337@linux.site> User-Agent: quilt/0.47-14.9 Date: Tue, 30 Mar 2010 15:57:57 -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, Hans de Goede , Jean Delvare , Jean Delvare , Greg Kroah-Hartman Subject: [55/89] hwmon: (fschmd) Fix a memleak on multiple opens of /dev/watchdog In-Reply-To: <20100330230520.GA28779@kroah.com> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org 2.6.31-stable review patch. If anyone has any objections, please let us know. ------------------ commit c453615f77aa51593c1c9c9031b4278797d3fd19 upstream. When /dev/watchdog gets opened a second time we return -EBUSY, but we already have got a kref then, so we end up leaking our data struct. Signed-off-by: Hans de Goede Signed-off-by: Jean Delvare Acked-by: Jean Delvare Signed-off-by: Greg Kroah-Hartman --- drivers/hwmon/fschmd.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) --- a/drivers/hwmon/fschmd.c +++ b/drivers/hwmon/fschmd.c @@ -767,6 +767,7 @@ leave: static int watchdog_open(struct inode *inode, struct file *filp) { struct fschmd_data *pos, *data = NULL; + int watchdog_is_open; /* We get called from drivers/char/misc.c with misc_mtx hold, and we call misc_register() from fschmd_probe() with watchdog_data_mutex @@ -781,10 +782,12 @@ static int watchdog_open(struct inode *i } } /* Note we can never not have found data, so we don't check for this */ - kref_get(&data->kref); + watchdog_is_open = test_and_set_bit(0, &data->watchdog_is_open); + if (!watchdog_is_open) + kref_get(&data->kref); mutex_unlock(&watchdog_data_mutex); - if (test_and_set_bit(0, &data->watchdog_is_open)) + if (watchdog_is_open) return -EBUSY; /* Start the watchdog */