Re: [PATCH] wifi: wfx: repair open network AP mode

["Jérôme Pouiller" <jerome.pouiller@silabs.com>]

On Friday 23 August 2024 15:15:20 CEST A. Sverdlin wrote:
> 
> From: Alexander Sverdlin <alexander.sverdlin@siemens.com>
> 
> RSN IE missing in beacon is normal in open networks.
> Avoid returning -ENODEV in this case.
> 
> Steps to reproduce:
> 
> $ cat /etc/wpa_supplicant.conf
> network={
>         ssid="testNet"
>         mode=2
>         key_mgmt=NONE
> }
> 
> $ wpa_supplicant -iwlan0 -c /etc/wpa_supplicant.conf
> nl80211: Beacon set failed: -22 (Invalid argument)
> Failed to set beacon parameters
> Interface initialization failed
> wlan0: interface state UNINITIALIZED->DISABLED
> wlan0: AP-DISABLED
> wlan0: Unable to setup interface.
> Failed to initialize AP interface
> 
> After the change:
> 
> $ wpa_supplicant -iwlan0 -c /etc/wpa_supplicant.conf
> Successfully initialized wpa_supplicant
> wlan0: interface state UNINITIALIZED->ENABLED
> wlan0: AP-ENABLED

Good catch, thank you.

> 
> Cc: stable@vger.kernel.org
> Fixes: fe0a7776d4d1 ("wifi: wfx: fix possible NULL pointer dereference in wfx_set_mfp_ap()")
> Signed-off-by: Alexander Sverdlin <alexander.sverdlin@siemens.com>
> ---
>  drivers/net/wireless/silabs/wfx/sta.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/drivers/net/wireless/silabs/wfx/sta.c b/drivers/net/wireless/silabs/wfx/sta.c
> index 216d43c8bd6e..7c04810dbf3d 100644
> --- a/drivers/net/wireless/silabs/wfx/sta.c
> +++ b/drivers/net/wireless/silabs/wfx/sta.c
> @@ -352,8 +352,11 @@ static int wfx_set_mfp_ap(struct wfx_vif *wvif)
> 
>         ptr = (u16 *)cfg80211_find_ie(WLAN_EID_RSN, skb->data + ieoffset,
>                                       skb->len - ieoffset);
> -       if (unlikely(!ptr))
> +       if (!ptr) {
> +               /* No RSN IE is fine in open networks */
> +               ret = 0;
>                 goto free_skb;
> +       }
> 
>         ptr += pairwise_cipher_suite_count_offset;
>         if (WARN_ON(ptr > (u16 *)skb_tail_pointer(skb)))

wfx_hif_set_mfp() is no more called when open network is started. Normally,
wfx_hif_reset() is sufficient to avoid any side effect with previous calls
to wfx_hif_set_mfp().

However, if you don't mind, I would prefer to call wfx_hif_set_mfp() in all
cases.

-- 
Jérôme Pouiller