[PATCH 03/10] wifi: cfg80211: extend interface combination check for multi-radio

[Johannes Berg]

On Thu, 2024-06-20 at 13:11 +0200, Felix Fietkau wrote:
> 
> +static inline u32
> +rdev_get_radio_mask(struct cfg80211_registered_device *rdev,
> +		    struct net_device *dev)
> +{
> +	struct wiphy *wiphy = &rdev->wiphy;
> +	u32 ret;
> +
> +	if (!rdev->ops->get_radio_mask)
> +		return 0;
> +
> +	trace_rdev_get_radio_mask(wiphy, dev);
> +	ret = rdev->ops->get_radio_mask(wiphy, dev);
> +	trace_rdev_return_int(wiphy, ret);

I'd tend to prefer tracing even if it's not implemented, so we see
what's going on? Though personally I guess in this case I don't even
care much since mac80211 will unconditionally implement it ...

> @@ -2366,14 +2374,19 @@ int cfg80211_iter_combinations(struct wiphy *wiphy,
>  					    void *data),
>  			       void *data)
>  {
> +	const struct wiphy_radio *radio = NULL;
> +	const struct ieee80211_iface_combination *c, *cs;
>  	const struct ieee80211_regdomain *regdom;
>  	enum nl80211_dfs_regions region = 0;
> -	int i, j, iftype;
> +	int i, j, n, iftype;
>  	int num_interfaces = 0;
>  	u32 used_iftypes = 0;
>  	u32 beacon_int_gcd;
>  	bool beacon_int_different;
>  
> +	if (params->radio_idx >= 0)
> +		radio = &wiphy->radio[params->radio_idx];

Maybe we should have a sanity bounds check?

Or even really just __counted_by() annotations in struct wiphy_radio, so
we can run with UBSAN in testing (which would be a comment for patch 2,
but I'm not going to send it there again ;-) ).

johannes