Re: [PATCH net-next v3 0/3] net: ipvlan: fix potential UAF problem for phy_dev

[Paolo Abeni]

Hello,

On Sat, 2022-03-19 at 17:52 +0800, Ziyang Xuan wrote:
> There is a known scenario can trigger UAF problem for lower
> netdevice as following:
> 
> Someone module puts the NETDEV_UNREGISTER event handler to a
> work, and lower netdevice is accessed in the work handler. But
> when the work is excuted, lower netdevice has been destroyed
> because upper netdevice did not get reference to lower netdevice
> correctly.
> 
> Although it can not happen for ipvlan now because there is no
> way to access phy_dev outside ipvlan. But it is necessary to
> add the reference operation to phy_dev to avoid the potential
> UAF problem in the future.
> 
> In addition, add net device refcount tracker to ipvlan and
> fix some error comments for ipvtap module.

This is pure net-next material, and we are now into the merge window -
only fixes allowed. Please repost in 2w, thanks!

Paolo