Re: [PATCH net] net: pse-pd: scope pse_control regulator handle to kref lifetime

[Simon Horman]

On Wed, Jun 24, 2026 at 10:38:38PM +0200, Carlo Szelinsky wrote:
> On Wed, 24 Jun 2026 16:12:51 +0100, Simon Horman wrote:
> > This is an AI-generated review of your patch. The human sending this
> > email has considered the AI review valid, or at least plausible.
> [...]
> > [High]
> > Does this fix the use-after-free completely, or only the regulator-put
> > part of it?
> [...]
> > Would a more complete fix also need pse_controller_unregister() to
> > drain outstanding pse_control references, or have pse_control hold a
> > refcount on pcdev, so that psec cannot outlive pcdev->pi and pcdev?
> 
> Thanks, the review is correct. This patch only fixes the regulator
> handle. In the same unbind-while-held case __pse_control_release()
> also reads psec->pcdev->pi[] and psec->pcdev->owner after
> pse_controller_unregister() has freed pcdev->pi, so those are still
> use-after-free reads on their own.
> 
> That wider problem is exactly what you describe: the controller does
> not drain its outstanding pse_control references on unregister. It is
> fixed by draining them, which is what the PSE notifier series does --
> PSE_UNREGISTERED drops every phydev->psec before pse_release_pis()
> frees pcdev->pi. This patch is patch 1 of that series (by Corey
> Leavitt); the rest targets net-next and is deferred until it reopens:
> 
>   https://lore.kernel.org/netdev/20260620112440.1734404-1-github@xxxxxxxxxxxx/
> 
> Jakub suggested sending this one to net on its own since it is a fix,
> so it is here without the notifier patches. My v1 commit message
> overclaimed by saying it makes __pse_control_release() correct
> regardless of the controller's devres state, which is only true for
> the regulator handle. I have reworded it in v2 to scope it to the
> regulator put and to point at the series for the wider lifetime fix.
> 
> Does you agree? Another option would be to wait for the entire series.

Thanks for the clarification.
Yes, I agree this is a good approach.