[PATCH] mac80211: fix low throughput due to invalid addba extension

[Johannes Berg]

On Tue, 2021-03-16 at 21:17 +0530, Govindaraj wrote:
> Addba request action frame received with the extension element from
> certain 11ac stations,
> 

Please indicate which so we have a record of who's shipping broken junk.

> but the cmd id and length not matching to addba
> extension and it failing in element parsing.

> Due to this, addba request
> not acknowledged and aggregation not started which is causing low
> throughput. Hence validating the cmd id before processing addba extension.

>  	ies_len = len - offsetof(struct ieee80211_mgmt,
>  				 u.action.u.addba_req.variable);
> -	if (ies_len) {
> +	if (ies_len &&
> +	    mgmt->u.action.u.addba_req.variable[0] == WLAN_EID_ADDBA_EXT) {
>  		ieee802_11_parse_elems(mgmt->u.action.u.addba_req.variable,
>                                  ies_len, true, &elems, mgmt->bssid, NULL);
>  		if (elems.parse_error)

So we get into parse_error without this?

What are they putting there instead?

johannes