From c453615f77aa51593c1c9c9031b4278797d3fd19 Mon Sep 17 00:00:00 2001 From: Hans de Goede Date: Mon, 25 Jan 2010 15:00:50 +0100 Subject: [PATCH] hwmon: (fschmd) Fix a memleak on multiple opens of /dev/watchdog 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 Cc: stable@kernel.org --- drivers/hwmon/fschmd.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) diff --git a/drivers/hwmon/fschmd.c b/drivers/hwmon/fschmd.c index bd0fc67e804b..fa0728232e71 100644 --- a/drivers/hwmon/fschmd.c +++ b/drivers/hwmon/fschmd.c @@ -768,6 +768,7 @@ 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 @@ -782,10 +783,12 @@ static int watchdog_open(struct inode *inode, struct file *filp) } } /* 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 */ -- 2.20.1