[PATCH 1/2] wpa_supplicant: Handle randomization changes for same ESS

[Jouni Malinen]

On Thu, Dec 01, 2022 at 04:43:43PM +0100, Andrzej Ostruszka wrote:
> When MAC randomization settings change we should use new MAC address
> even if we are associating to the same ESS.  For example consider this
> scenario:
> - hardware MAC is being used,
> - we disconnect from the network,
> - policy/style is changed via D-Bus to turn randomization on,
> - we reconnect to the same network.
> 
> In the last step the randomized address should be used.
> 
> Changes to the randomization settings include both changes to the
> policy/style to be used and changes to the pregenerated MAC address
> value in case of mac_addr==3.

That sounds reasonable, but one of the changes seems problematic:

> diff --git a/wpa_supplicant/wpa_supplicant.c b/wpa_supplicant/wpa_supplicant.c
> @@ -2436,7 +2445,7 @@ void wpa_supplicant_associate(struct wpa_supplicant *wpa_s,
>  	wpa_s_setup_sae_pt(wpa_s->conf, ssid);
>  #endif /* CONFIG_SAE */
>  
> -	if (rand_style > 0 && !wpa_s->reassoc_same_ess) {
> +	if (rand_style > 0) {
>  		if (wpas_update_random_addr(wpa_s, rand_style, ssid) < 0)
>  			return;
>  		wpa_sm_pmksa_cache_flush(wpa_s->wpa, ssid);

Wouldn't this disable PMKSA caching completely for all rand_style > 0
cases? In particular, this flushing of the PMKSA cache entries seems
undesired for rand_style==3 when reassociating within the ESS using the
same MAC address.
 
-- 
Jouni Malinen                                            PGP id EFC895FA