Received-SPF: pass (google.com: domain of linux-wireless-owner@vger.kernel.org designates 23.128.96.18 as permitted sender) client-ip=23.128.96.18;
Message-ID: <b02735cc844c9ba2222d23a7e6ad112a82a36891.camel@sipsolutions.net>
Subject: Re: [PATCH v4 5/6] mac80211: use ieee802_11_parse_elems() to find
 ies instead of ieee80211_bss_get_ie()
From:   Johannes Berg <johannes@sipsolutions.net>
To:     Wen Gong <wgong@codeaurora.org>, ath11k@lists.infradead.org
Cc:     linux-wireless@vger.kernel.org
Date:   Fri, 24 Sep 2021 12:13:36 +0200
In-Reply-To: <20210924100052.32029-6-wgong@codeaurora.org>
References: <20210924100052.32029-1-wgong@codeaurora.org>
         <20210924100052.32029-6-wgong@codeaurora.org>
Content-Type: text/plain; charset="UTF-8"
User-Agent: Evolution 3.38.4 (3.38.4-1.fc33) 
MIME-Version: 1.0
Content-Transfer-Encoding: 8bit
Precedence: bulk

Taking a brief look before lunch,

>  	if (!(ifmgd->flags & IEEE80211_STA_DISABLE_HT) && !is_6ghz) {
>  		const u8 *ht_oper_ie, *ht_cap_ie;
>  
> 
> 
> 
> -		ht_oper_ie = ieee80211_bss_get_ie(cbss, WLAN_EID_HT_OPERATION);
> +		ht_oper_ie = elems->ht_operation ?
> +			((const u8 *)elems->ht_operation) - 2 :
> +			NULL;
>  		if (ht_oper_ie && ht_oper_ie[1] >= sizeof(*ht_oper))
>  			ht_oper = (void *)(ht_oper_ie + 2);

Can't we drop these checks, and simply do

ht_oper = elems->ht_operation?

After all, ieee802_11_parse_elems() should already be doing the
necessary length checks? We just didn't have that with
ieee80211_bss_get_ie().

> -		ht_cap_ie = ieee80211_bss_get_ie(cbss, WLAN_EID_HT_CAPABILITY);
> +		ht_cap_ie = elems->ht_cap_elem ?
> +			((const u8 *)elems->ht_cap_elem) - 2 :
> +			NULL;
>  		if (ht_cap_ie && ht_cap_ie[1] >= sizeof(*ht_cap))
>  			ht_cap = (void *)(ht_cap_ie + 2);

Likewise for all the others.

johannes