From: Jouni Hogander <jouni.hogander@xxxxxxxxxx> commit e0b60903b434a7ee21ba8d8659f207ed84101e89 upstream. Dev_hold has to be called always in netdev_queue_add_kobject. Otherwise usage count drops below 0 in case of failure in kobject_init_and_add. Fixes: b8eb718348b8 ("net-sysfs: Fix reference count leak in rx|netdev_queue_add_kobject") Reported-by: Hulk Robot <hulkci@xxxxxxxxxx> Cc: Tetsuo Handa <penguin-kernel@xxxxxxxxxxxxxxxxxxx> Cc: David Miller <davem@xxxxxxxxxxxxx> Cc: Lukas Bulwahn <lukas.bulwahn@xxxxxxxxx> Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx> Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx> --- net/core/net-sysfs.c | 7 +++++-- 1 file changed, 5 insertions(+), 2 deletions(-) --- a/net/core/net-sysfs.c +++ b/net/core/net-sysfs.c @@ -1469,14 +1469,17 @@ static int netdev_queue_add_kobject(stru struct kobject *kobj = &queue->kobj; int error = 0; + /* Kobject_put later will trigger netdev_queue_release call + * which decreases dev refcount: Take that reference here + */ + dev_hold(queue->dev); + kobj->kset = dev->queues_kset; error = kobject_init_and_add(kobj, &netdev_queue_ktype, NULL, "tx-%u", index); if (error) goto err; - dev_hold(queue->dev); - #ifdef CONFIG_BQL error = sysfs_create_group(kobj, &dql_group); if (error)