diff mbox series

mac80211: process S1G Operation element before HT

Message ID 20200929181948.22894-1-thomas@adapt-ip.com (mailing list archive)
State Superseded
Delegated to: Johannes Berg
Headers show
Series mac80211: process S1G Operation element before HT | expand

Commit Message

Thomas Pedersen Sept. 29, 2020, 6:19 p.m. UTC
The sband->ht_cap was being processed before S1G Operation
element.  Since the HT capability element should not be
present on the S1G band, avoid processing potential
garbage by moving the call to
ieee80211_apply_htcap_overrides() to after the S1G block.

Signed-off-by: Thomas Pedersen <thomas@adapt-ip.com>
---
 net/mac80211/mlme.c | 6 +++---
 1 file changed, 3 insertions(+), 3 deletions(-)

Comments

Johannes Berg Sept. 29, 2020, 6:32 p.m. UTC | #1
On Tue, 2020-09-29 at 11:19 -0700, Thomas Pedersen wrote:
> The sband->ht_cap was being processed before S1G Operation
> element.  Since the HT capability element should not be
> present on the S1G band, avoid processing potential
> garbage by moving the call to
> ieee80211_apply_htcap_overrides() to after the S1G block.

Ah, heh. I hadn't even realized that.

What I meant though was something else: we have

        if (s1g_oper && sband->band == NL80211_BAND_S1GHZ) {
		...
		goto out;
	}

	// process ht cap overrides (after this patch)

	// check HT oper

	// check VHT oper

	// ...

So given that first condition, if you actually have an S1G AP *without*
S1G operation element (for some reason), you'd start processing HT, VHT,
and whatever else capabilities, sending us down a misleading and likely
very confusing path, which seems like it should be avoided?

johannes
Thomas Pedersen Sept. 29, 2020, 6:44 p.m. UTC | #2
On 2020-09-29 11:32, Johannes Berg wrote:
> On Tue, 2020-09-29 at 11:19 -0700, Thomas Pedersen wrote:
>> The sband->ht_cap was being processed before S1G Operation
>> element.  Since the HT capability element should not be
>> present on the S1G band, avoid processing potential
>> garbage by moving the call to
>> ieee80211_apply_htcap_overrides() to after the S1G block.
> 
> Ah, heh. I hadn't even realized that.
> 
> What I meant though was something else: we have
> 
>         if (s1g_oper && sband->band == NL80211_BAND_S1GHZ) {
> 		...
> 		goto out;
> 	}
> 
> 	// process ht cap overrides (after this patch)
> 
> 	// check HT oper
> 
> 	// check VHT oper
> 
> 	// ...
> 
> So given that first condition, if you actually have an S1G AP *without*
> S1G operation element (for some reason), you'd start processing HT, 
> VHT,
> and whatever else capabilities, sending us down a misleading and likely
> very confusing path, which seems like it should be avoided?

Ah ok, yes the !s1g_oper case. I'll take a look.
diff mbox series

Patch

diff --git a/net/mac80211/mlme.c b/net/mac80211/mlme.c
index 38e87ac9902e..80b4d46d0b20 100644
--- a/net/mac80211/mlme.c
+++ b/net/mac80211/mlme.c
@@ -174,9 +174,6 @@  ieee80211_determine_chantype(struct ieee80211_sub_if_data *sdata,
 		goto out;
 	}
 
-	memcpy(&sta_ht_cap, &sband->ht_cap, sizeof(sta_ht_cap));
-	ieee80211_apply_htcap_overrides(sdata, &sta_ht_cap);
-
 	if (s1g_oper && sband->band == NL80211_BAND_S1GHZ) {
 		ieee80211_chandef_s1g_oper(s1g_oper, chandef);
 		ret = IEEE80211_STA_DISABLE_HT | IEEE80211_STA_DISABLE_40MHZ |
@@ -186,6 +183,9 @@  ieee80211_determine_chantype(struct ieee80211_sub_if_data *sdata,
 		goto out;
 	}
 
+	memcpy(&sta_ht_cap, &sband->ht_cap, sizeof(sta_ht_cap));
+	ieee80211_apply_htcap_overrides(sdata, &sta_ht_cap);
+
 	if (!ht_oper || !sta_ht_cap.ht_supported) {
 		ret = IEEE80211_STA_DISABLE_HT |
 		      IEEE80211_STA_DISABLE_VHT |