From 90f7453adee2bcad39c6630b760358eb799f238d Mon Sep 17 00:00:00 2001 From: Andrew de Quincey Date: Tue, 4 Apr 2006 13:41:47 +0100 Subject: Fix mutex in dvb_register_device to work. From: Andrew de Quincey This mutex is meant to stop two devices getting the same ID. dvbdev_get_free_id() scans the list of already allocated devices to find a free id. Unfortunately, since the mutex is unlocked before the card is added to the above list, it is still possible for two of them to get the same id. Solution: move the mutex after the list_add. Its debatable whether this mutex lock is actually needed, but I'm unwilling to just remove it in case something does depend on it. Signed-off-by: Andrew de Quincey --- linux/drivers/media/dvb/dvb-core/dvbdev.c | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) (limited to 'linux/drivers/media/dvb/dvb-core/dvbdev.c') diff --git a/linux/drivers/media/dvb/dvb-core/dvbdev.c b/linux/drivers/media/dvb/dvb-core/dvbdev.c index 9b824c31b..041ed7fd1 100644 --- a/linux/drivers/media/dvb/dvb-core/dvbdev.c +++ b/linux/drivers/media/dvb/dvb-core/dvbdev.c @@ -230,8 +230,6 @@ int dvb_register_device(struct dvb_adapter *adap, struct dvb_device **pdvbdev, return -ENOMEM; } - mutex_unlock(&dvbdev_register_lock); - memcpy(dvbdev, template, sizeof(struct dvb_device)); dvbdev->type = type; dvbdev->id = id; @@ -242,6 +240,8 @@ int dvb_register_device(struct dvb_adapter *adap, struct dvb_device **pdvbdev, list_add_tail (&dvbdev->list_head, &adap->device_list); + mutex_unlock(&dvbdev_register_lock); + devfs_mk_cdev(MKDEV(DVB_MAJOR, nums2minor(adap->num, type, id)), S_IFCHR | S_IRUSR | S_IWUSR, "dvb/adapter%d/%s%d", adap->num, dnames[type], id); -- cgit v1.2.3