Re: [PATCH RESEND] wifi: mt76: mt7996: fix NULL pointer dereference in mt7996_mcu_sta_bfer_he

[Greg KH <greg@kroah.com>]

On Tue, Sep 03, 2024 at 09:39:13AM +0800, Ma Ke wrote:
> Fix the NULL pointer dereference in mt7996_mcu_sta_bfer_he
> routine adding an sta interface to the mt7996 driver.
> 
> Found by code review.
> 
> Cc: stable@vger.kernel.org
> Fixes: 98686cd21624 ("wifi: mt76: mt7996: add driver for MediaTek Wi-Fi 7 (802.11be) devices")
> Signed-off-by: Ma Ke <make24@iscas.ac.cn>
> ---
>  drivers/net/wireless/mediatek/mt76/mt7996/mcu.c | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/drivers/net/wireless/mediatek/mt76/mt7996/mcu.c b/drivers/net/wireless/mediatek/mt76/mt7996/mcu.c
> index 2e4fa9f48dfb..cba28d8d5562 100644
> --- a/drivers/net/wireless/mediatek/mt76/mt7996/mcu.c
> +++ b/drivers/net/wireless/mediatek/mt76/mt7996/mcu.c
> @@ -1544,6 +1544,9 @@ mt7996_mcu_sta_bfer_he(struct ieee80211_sta *sta, struct ieee80211_vif *vif,
>  	u8 nss_mcs = mt7996_mcu_get_sta_nss(mcs_map);
>  	u8 snd_dim, sts;
>  
> +	if (!vc)
> +		return;

Why is this the only place you are checking the return value of
mt76_connac_get_he_phy_cap()?  Either fix them all in this driver or
none as obviously it can not fail :(

thanks,

greg k-h