[PATCH 1/2] mac80211: set IEEE80211_TX_CTRL_PORT_CTRL_PROTO for nl80211 TX

[PATCH 1/2] mac80211: set IEEE80211_TX_CTRL_PORT_CTRL_PROTO for nl80211 TX

[Johannes Berg]

From: Johannes Berg <johannes.berg@intel.com>

When a frame is transmitted via the nl80211 TX rather than as a
normal frame, IEEE80211_TX_CTRL_PORT_CTRL_PROTO wasn't set and
this will lead to wrong decisions (rate control etc.) being made
about the frame; fix this.

Fixes: 911806491425 ("mac80211: Add support for tx_control_port")
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
---
 net/mac80211/tx.c | 8 ++++++--
 1 file changed, 6 insertions(+), 2 deletions(-)

diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index 7dbfb9e3cd84..bc1c27dc8dd5 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -5,7 +5,7 @@
  * Copyright 2006-2007	Jiri Benc <jbenc@suse.cz>
  * Copyright 2007	Johannes Berg <johannes@sipsolutions.net>
  * Copyright 2013-2014  Intel Mobile Communications GmbH
- * Copyright (C) 2018 Intel Corporation
+ * Copyright (C) 2018, 2020 Intel Corporation
  *
  * Transmit and frame generation functions.
  */
@@ -5132,6 +5132,7 @@ int ieee80211_tx_control_port(struct wiphy *wiphy, struct net_device *dev,
 	struct ieee80211_local *local = sdata->local;
 	struct sk_buff *skb;
 	struct ethhdr *ehdr;
+	u32 ctrl_flags = 0;
 	u32 flags;
 
 	/* Only accept CONTROL_PORT_PROTOCOL configured in CONNECT/ASSOCIATE
@@ -5141,6 +5142,9 @@ int ieee80211_tx_control_port(struct wiphy *wiphy, struct net_device *dev,
 	    proto != cpu_to_be16(ETH_P_PREAUTH))
 		return -EINVAL;
 
+	if (proto == sdata->control_port_protocol)
+		ctrl_flags |= IEEE80211_TX_CTRL_PORT_CTRL_PROTO;
+
 	if (unencrypted)
 		flags = IEEE80211_TX_INTFL_DONT_ENCRYPT;
 	else
@@ -5166,7 +5170,7 @@ int ieee80211_tx_control_port(struct wiphy *wiphy, struct net_device *dev,
 	skb_reset_mac_header(skb);
 
 	local_bh_disable();
-	__ieee80211_subif_start_xmit(skb, skb->dev, flags, 0);
+	__ieee80211_subif_start_xmit(skb, skb->dev, flags, ctrl_flags);
 	local_bh_enable();
 
 	return 0;
-- 
2.25.1

[PATCH 2/2] mac80211: remove ieee80211_tx_h_check_control_port_protocol()

[Johannes Berg]

From: Johannes Berg <johannes.berg@intel.com>

This code is actually not ever effective, since the skb->protocol
isn't set up correctly (or at all) on outgoing frames. Also, we
already set the flags (except for IEEE80211_TX_CTL_USE_MINRATE)
in other code paths, and rate control already handles the frames
specially. Just remove it entirely.

Signed-off-by: Johannes Berg <johannes.berg@intel.com>
---
 net/mac80211/tx.c | 16 ----------------
 1 file changed, 16 deletions(-)

diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index bc1c27dc8dd5..5a37f7924af4 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -568,21 +568,6 @@ ieee80211_tx_h_ps_buf(struct ieee80211_tx_data *tx)
 		return ieee80211_tx_h_multicast_ps_buf(tx);
 }
 
-static ieee80211_tx_result debug_noinline
-ieee80211_tx_h_check_control_port_protocol(struct ieee80211_tx_data *tx)
-{
-	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(tx->skb);
-
-	if (unlikely(tx->sdata->control_port_protocol == tx->skb->protocol)) {
-		if (tx->sdata->control_port_no_encrypt)
-			info->flags |= IEEE80211_TX_INTFL_DONT_ENCRYPT;
-		info->control.flags |= IEEE80211_TX_CTRL_PORT_CTRL_PROTO;
-		info->flags |= IEEE80211_TX_CTL_USE_MINRATE;
-	}
-
-	return TX_CONTINUE;
-}
-
 static ieee80211_tx_result debug_noinline
 ieee80211_tx_h_select_key(struct ieee80211_tx_data *tx)
 {
@@ -1775,7 +1760,6 @@ static int invoke_tx_handlers_early(struct ieee80211_tx_data *tx)
 	CALL_TXH(ieee80211_tx_h_dynamic_ps);
 	CALL_TXH(ieee80211_tx_h_check_assoc);
 	CALL_TXH(ieee80211_tx_h_ps_buf);
-	CALL_TXH(ieee80211_tx_h_check_control_port_protocol);
 	CALL_TXH(ieee80211_tx_h_select_key);
 	if (!ieee80211_hw_check(&tx->local->hw, HAS_RATE_CONTROL))
 		CALL_TXH(ieee80211_tx_h_rate_ctrl);
-- 
2.25.1

Re: [PATCH 2/2] mac80211: remove ieee80211_tx_h_check_control_port_protocol()

[Johannes Berg]

On Thu, 2020-03-26 at 15:53 +0100, Johannes Berg wrote:
> From: Johannes Berg <johannes.berg@intel.com>
> 
> This code is actually not ever effective, since the skb->protocol
> isn't set up correctly (or at all) on outgoing frames. Also, we
> already set the flags (except for IEEE80211_TX_CTL_USE_MINRATE)
> in other code paths, and rate control already handles the frames
> specially. Just remove it entirely.
> 

Thread necromancy alert ...

But for my own information (and everyone else who cares):

This breaks a couple of hwsim test cases, for example
ap_wpa2_psk_no_control_port.

johannes