This is a note to let you know that I've just added the patch titled
bonding: init notify_work earlier to avoid uninitialized use
to the 4.4-stable tree which can be found at:
http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary
The filename of the patch is:
bonding-init-notify_work-earlier-to-avoid-uninitiali.patch
and it can be found in the queue-4.4 subdirectory.
If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.
commit a7a591a05917cc634d8fc88cf235ab24aa35857a
Author: Johannes Berg <johannes.berg@xxxxxxxxx>
Date: Mon May 17 16:13:35 2021 +0200
bonding: init notify_work earlier to avoid uninitialized use
[ Upstream commit 35d96e631860226d5dc4de0fad0a415362ec2457 ]
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@xxxxxxxxxxxxxxxxxxxxxxxxx
Signed-off-by: Johannes Berg <johannes.berg@xxxxxxxxx>
Acked-by: Jay Vosburgh <jay.vosburgh@xxxxxxxxxxxxx>
Signed-off-by: David S. Miller <davem@xxxxxxxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
diff --git a/drivers/net/bonding/bond_main.c b/drivers/net/bonding/bond_main.c
index a33e8a3b5f0a..d6363ae22052 100644
--- a/drivers/net/bonding/bond_main.c
+++ b/drivers/net/bonding/bond_main.c
@@ -1267,6 +1267,7 @@ 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;
@@ -1279,7 +1280,6 @@ static struct slave *bond_alloc_slave(struct bonding *bond,
return NULL;
}
}
- INIT_DELAYED_WORK(&slave->notify_work, bond_netdev_notify_work);
return slave;
}
