From 35d96e631860226d5dc4de0fad0a415362ec2457 Mon Sep 17 00:00:00 2001 From: Johannes Berg Date: Mon, 17 May 2021 16:13:35 +0200 Subject: [PATCH] bonding: init notify_work earlier to avoid uninitialized use If bond_kobj_init() or later kzalloc() in bond_alloc_slave() fail, then we call kobject_put() on the slave->kobj. This in turn calls the release function slave_kobj_release() which will always try to cancel_delayed_work_sync(&slave->notify_work), which shouldn't be done on an uninitialized work struct. Always initialize the work struct earlier to avoid problems here. Syzbot bisected this down to a completely pointless commit, some fault injection may have been at work here that caused the alloc failure in the first place, which may interact badly with bisect. Reported-by: syzbot+bfda097c12a00c8cae67@syzkaller.appspotmail.com Signed-off-by: Johannes Berg Acked-by: Jay Vosburgh Signed-off-by: David S. Miller --- drivers/net/bonding/bond_main.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c index 20bbda1b36e1..c5a646d06102 100644 --- a/drivers/net/bonding/bond_main.c +++ b/drivers/net/bonding/bond_main.c @@ -1526,6 +1526,7 @@ static struct slave *bond_alloc_slave(struct bonding *bond, slave->bond = bond; slave->dev = slave_dev; + INIT_DELAYED_WORK(&slave->notify_work, bond_netdev_notify_work); if (bond_kobj_init(slave)) return NULL; @@ -1538,7 +1539,6 @@ static struct slave *bond_alloc_slave(struct bonding *bond, return NULL; } } - INIT_DELAYED_WORK(&slave->notify_work, bond_netdev_notify_work); return slave; }