[PATCH] wpa_supplicant: Cache PMK for 802.1X 4-way handshake offload

[Chung-Hsien Hsu]

On Tue, Aug 04, 2026 at 10:48:02AM +0200, Jouni Malinen wrote:
> It would be good to state that more clearly in the commit message since
> that part about PMKSA caching not being available was not obvious since
> the focused more on storing the PMK rather than adding a PMKSA cache
> entry.

Agreed. I will update the commit message to make the missing PMKSA cache
entry and its impact on subsequent connections clearer.

> If the main point here is in adding that PMKSA cache entry, why the
> changes allow wpa_sm_set_pmk() to be called with auth_addr == NULL which
> is explicitly documented to not cache the PMK? I can understand the need
> to create a PMKSA cache entry, but what is the need, if any, to set
> sm->pmk?

The original change was intended to mirror the host-driven EAPOL-Key
path by storing the PMK in the WPA state machine as well as creating a
PMKSA cache entry where applicable.

After looking at this more closely, there is no specific need to update
sm->pmk for the driver-offloaded 4-way handshake itself. The actual
issue is the missing PMKSA cache entry.

I'll revise the patch so that wpa_sm_set_pmk() is called only when PMKSA
caching is applicable and a valid authenticator address is available,
and send a v2.

Chung-Hsien