[PATCH wireless-next 1/2] wifi: mac80211_hwsim: report the TX link of frames sent via wmediumd

[PATCH wireless-next 1/2] wifi: mac80211_hwsim: report the TX link of frames sent via wmediumd

[Felix Fietkau]

Since commit f15350104130 ("wifi: mac80211_hwsim: report TX status
link_id"), hwsim_tx_info_frame_received_nl() passes txi->control.vif to
mac80211_hwsim_get_link_id(). It does so after
ieee80211_tx_info_clear_status(), which zeroes that field, and
mac80211_hwsim_tx_frame_nl() already stored the frame cookie in the
same memory. The lookup thus never finds a link, and a TX status from
wmediumd or virtio never carries a link ID.

Look up the link when the frame is handed to wmediumd, and keep it with
the cookie in the driver data of the frame.

Fixes: f15350104130 ("wifi: mac80211_hwsim: report TX status link_id")
Signed-off-by: Felix Fietkau <nbd@nbd.name>
---
 .../wireless/virtual/mac80211_hwsim_main.c    | 79 ++++++++++++-------
 1 file changed, 51 insertions(+), 28 deletions(-)

diff --git a/drivers/net/wireless/virtual/mac80211_hwsim_main.c b/drivers/net/wireless/virtual/mac80211_hwsim_main.c
index c98c862678a2..2fb18a3c0667 100644
--- a/drivers/net/wireless/virtual/mac80211_hwsim_main.c
+++ b/drivers/net/wireless/virtual/mac80211_hwsim_main.c
@@ -1643,6 +1643,45 @@ static void mac80211_hwsim_write_tsf(struct mac80211_hwsim_data *data,
 	spin_unlock_bh(&data->tsf_offset_lock);
 }
 
+struct hwsim_tx_cb {
+	int cookie;
+	s8 link_id;
+};
+
+static struct hwsim_tx_cb *hwsim_tx_cb(struct sk_buff *skb)
+{
+	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
+
+	BUILD_BUG_ON(sizeof(struct hwsim_tx_cb) >
+		     sizeof(info->rate_driver_data));
+	return (void *)info->rate_driver_data;
+}
+
+static int mac80211_hwsim_get_link_id(struct ieee80211_vif *vif,
+				      struct ieee80211_hdr *hdr)
+{
+	int i, link_id = -1;
+
+	if (!vif || !ieee80211_vif_is_mld(vif))
+		return -1;
+
+	rcu_read_lock();
+	for (i = 0; i < IEEE80211_MLD_MAX_NUM_LINKS; i++) {
+		struct ieee80211_bss_conf *link_conf;
+
+		link_conf = rcu_dereference(vif->link_conf[i]);
+		if (!link_conf)
+			continue;
+		if (ether_addr_equal(link_conf->addr, hdr->addr2)) {
+			link_id = i;
+			break;
+		}
+	}
+	rcu_read_unlock();
+
+	return link_id;
+}
+
 static void mac80211_hwsim_tx_frame_nl(struct ieee80211_hw *hw,
 				       struct sk_buff *my_skb,
 				       int dst_portid,
@@ -1652,6 +1691,8 @@ static void mac80211_hwsim_tx_frame_nl(struct ieee80211_hw *hw,
 	struct mac80211_hwsim_data *data = hw->priv;
 	struct ieee80211_hdr *hdr = (struct ieee80211_hdr *) my_skb->data;
 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(my_skb);
+	struct hwsim_tx_cb *cb;
+	int link_id;
 	void *msg_head;
 	unsigned int hwsim_flags = 0;
 	int i;
@@ -1729,9 +1770,13 @@ static void mac80211_hwsim_tx_frame_nl(struct ieee80211_hw *hw,
 		    tx_attempts_flags))
 		goto nla_put_failure;
 
+	link_id = mac80211_hwsim_get_link_id(info->control.vif, hdr);
+
 	/* We create a cookie to identify this skb */
 	cookie = atomic_inc_return(&data->pending_cookie);
-	info->rate_driver_data[0] = (void *)cookie;
+	cb = hwsim_tx_cb(my_skb);
+	cb->cookie = cookie;
+	cb->link_id = link_id;
 	if (nla_put_u64_64bit(skb, HWSIM_ATTR_COOKIE, cookie, HWSIM_ATTR_PAD))
 		goto nla_put_failure;
 
@@ -6361,27 +6406,6 @@ static void hwsim_register_wmediumd(struct net *net, u32 portid)
 	spin_unlock_bh(&hwsim_radio_lock);
 }
 
-static int mac80211_hwsim_get_link_id(struct ieee80211_vif *vif,
-				      struct ieee80211_hdr *hdr)
-{
-	int i;
-
-	if (!vif || !ieee80211_vif_is_mld(vif))
-		return -1;
-
-	for (i = 0; i < IEEE80211_MLD_MAX_NUM_LINKS; i++) {
-		struct ieee80211_bss_conf *link_conf;
-
-		link_conf = rcu_dereference(vif->link_conf[i]);
-		if (!link_conf)
-			continue;
-		if (ether_addr_equal(link_conf->addr, hdr->addr2))
-			return i;
-	}
-
-	return -1;
-}
-
 static int hwsim_tx_info_frame_received_nl(struct sk_buff *skb_2,
 					   struct genl_info *info)
 {
@@ -6394,7 +6418,7 @@ static int hwsim_tx_info_frame_received_nl(struct sk_buff *skb_2,
 	struct sk_buff *skb, *tmp;
 	const u8 *src;
 	unsigned int hwsim_flags;
-	int i;
+	int i, link_id;
 	unsigned long flags;
 	bool found = false;
 
@@ -6427,8 +6451,7 @@ static int hwsim_tx_info_frame_received_nl(struct sk_buff *skb_2,
 	skb_queue_walk_safe(&data2->pending, skb, tmp) {
 		uintptr_t skb_cookie;
 
-		txi = IEEE80211_SKB_CB(skb);
-		skb_cookie = (uintptr_t)txi->rate_driver_data[0];
+		skb_cookie = (uintptr_t)hwsim_tx_cb(skb)->cookie;
 
 		if (skb_cookie == ret_skb_cookie) {
 			__skb_unlink(skb, &data2->pending);
@@ -6452,6 +6475,7 @@ static int hwsim_tx_info_frame_received_nl(struct sk_buff *skb_2,
 
 	/* now send back TX status */
 	txi = IEEE80211_SKB_CB(skb);
+	link_id = hwsim_tx_cb(skb)->link_id;
 
 	ieee80211_tx_info_clear_status(txi);
 
@@ -6463,10 +6487,9 @@ static int hwsim_tx_info_frame_received_nl(struct sk_buff *skb_2,
 	txi->status.ack_signal = nla_get_u32(info->attrs[HWSIM_ATTR_SIGNAL]);
 
 	hdr = (struct ieee80211_hdr *)skb->data;
-	i = mac80211_hwsim_get_link_id(txi->control.vif, hdr);
-	if (i >= 0) {
+	if (link_id >= 0) {
 		txi->status.link_valid = 1;
-		txi->status.link_id = i;
+		txi->status.link_id = link_id;
 	}
 
 	if (!(hwsim_flags & HWSIM_TX_CTL_NO_ACK) &&
-- 
2.47.3

[PATCH wireless-next 2/2] wifi: mac80211_hwsim: restore MLD addresses before reporting TX status

[Felix Fietkau]

For a frame to an MLO station, mac80211_hwsim_tx() rewrites A1, A2 and
possibly A3 of the frame to link addresses, and then reports the TX
status on the same skb. ieee80211_tx_status_skb() looks up the station
by A1 and A2, which are now link addresses, and finds none. mac80211
then records no ACK, retry, lost frame or last TX rate for the station.

Put the original addresses back before the TX status is reported. For
frames sent via wmediumd, keep them in the driver data of the frame
until the status arrives. An all-zero A1 marks a frame without rewrite.

Fixes: 2ab60f49eb4d ("wifi: mac80211_hwsim: use MLO link ID for TX")
Signed-off-by: Felix Fietkau <nbd@nbd.name>
---
 .../wireless/virtual/mac80211_hwsim_main.c    | 37 +++++++++++++++----
 1 file changed, 30 insertions(+), 7 deletions(-)

diff --git a/drivers/net/wireless/virtual/mac80211_hwsim_main.c b/drivers/net/wireless/virtual/mac80211_hwsim_main.c
index 2fb18a3c0667..58d7a023392d 100644
--- a/drivers/net/wireless/virtual/mac80211_hwsim_main.c
+++ b/drivers/net/wireless/virtual/mac80211_hwsim_main.c
@@ -1645,6 +1645,7 @@ static void mac80211_hwsim_write_tsf(struct mac80211_hwsim_data *data,
 
 struct hwsim_tx_cb {
 	int cookie;
+	u8 orig_addrs[sizeof_field(struct ieee80211_hdr, addrs)];
 	s8 link_id;
 };
 
@@ -1657,6 +1658,16 @@ static struct hwsim_tx_cb *hwsim_tx_cb(struct sk_buff *skb)
 	return (void *)info->rate_driver_data;
 }
 
+static void hwsim_tx_addrs_restore(struct sk_buff *skb, const u8 *orig_addrs)
+{
+	struct ieee80211_hdr *hdr = (void *)skb->data;
+
+	if (is_zero_ether_addr(orig_addrs))
+		return;
+
+	memcpy(&hdr->addrs, orig_addrs, sizeof(hdr->addrs));
+}
+
 static int mac80211_hwsim_get_link_id(struct ieee80211_vif *vif,
 				      struct ieee80211_hdr *hdr)
 {
@@ -1685,7 +1696,8 @@ static int mac80211_hwsim_get_link_id(struct ieee80211_vif *vif,
 static void mac80211_hwsim_tx_frame_nl(struct ieee80211_hw *hw,
 				       struct sk_buff *my_skb,
 				       int dst_portid,
-				       struct ieee80211_channel *channel)
+				       struct ieee80211_channel *channel,
+				       const u8 *orig_addrs)
 {
 	struct sk_buff *skb;
 	struct mac80211_hwsim_data *data = hw->priv;
@@ -1777,6 +1789,10 @@ static void mac80211_hwsim_tx_frame_nl(struct ieee80211_hw *hw,
 	cb = hwsim_tx_cb(my_skb);
 	cb->cookie = cookie;
 	cb->link_id = link_id;
+	if (orig_addrs)
+		memcpy(cb->orig_addrs, orig_addrs, sizeof(cb->orig_addrs));
+	else
+		memset(cb->orig_addrs, 0, sizeof(cb->orig_addrs));
 	if (nla_put_u64_64bit(skb, HWSIM_ATTR_COOKIE, cookie, HWSIM_ATTR_PAD))
 		goto nla_put_failure;
 
@@ -2152,6 +2168,7 @@ static void mac80211_hwsim_tx(struct ieee80211_hw *hw,
 {
 	struct mac80211_hwsim_data *data = hw->priv;
 	struct ieee80211_tx_info *txi = IEEE80211_SKB_CB(skb);
+	u8 orig_addrs[sizeof_field(struct ieee80211_hdr, addrs)] = {};
 	struct ieee80211_hdr *hdr = (void *)skb->data;
 	struct ieee80211_chanctx_conf *chanctx_conf;
 	struct ieee80211_channel *channel;
@@ -2239,6 +2256,8 @@ static void mac80211_hwsim_tx(struct ieee80211_hw *hw,
 		 * probe response).
 		 */
 		if (sta && sta->mlo && link_sta) {
+			memcpy(orig_addrs, &hdr->addrs, sizeof(orig_addrs));
+
 			/* address translation to link addresses on TX */
 			ether_addr_copy(hdr->addr1, link_sta->addr);
 			ether_addr_copy(hdr->addr2, bss_conf->addr);
@@ -2313,7 +2332,8 @@ static void mac80211_hwsim_tx(struct ieee80211_hw *hw,
 	_portid = READ_ONCE(data->wmediumd);
 
 	if (_portid || hwsim_virtio_enabled)
-		return mac80211_hwsim_tx_frame_nl(hw, skb, _portid, channel);
+		return mac80211_hwsim_tx_frame_nl(hw, skb, _portid, channel,
+						  orig_addrs);
 
 	/* NO wmediumd detected, perfect medium simulation */
 	data->tx_pkts++;
@@ -2323,6 +2343,7 @@ static void mac80211_hwsim_tx(struct ieee80211_hw *hw,
 	if (ack && skb->len >= 16)
 		mac80211_hwsim_monitor_ack(channel, hdr->addr2);
 
+	hwsim_tx_addrs_restore(skb, orig_addrs);
 	ieee80211_tx_info_clear_status(txi);
 
 	/* frame was transmitted at most favorable rate at first attempt */
@@ -2471,7 +2492,7 @@ void mac80211_hwsim_tx_frame(struct ieee80211_hw *hw,
 	}
 
 	if (_portid || hwsim_virtio_enabled)
-		return mac80211_hwsim_tx_frame_nl(hw, skb, _portid, chan);
+		return mac80211_hwsim_tx_frame_nl(hw, skb, _portid, chan, NULL);
 
 	data->tx_pkts++;
 	data->tx_bytes += skb->len;
@@ -6417,8 +6438,9 @@ static int hwsim_tx_info_frame_received_nl(struct sk_buff *skb_2,
 	u64 ret_skb_cookie;
 	struct sk_buff *skb, *tmp;
 	const u8 *src;
+	struct hwsim_tx_cb tx_cb;
 	unsigned int hwsim_flags;
-	int i, link_id;
+	int i;
 	unsigned long flags;
 	bool found = false;
 
@@ -6475,7 +6497,7 @@ static int hwsim_tx_info_frame_received_nl(struct sk_buff *skb_2,
 
 	/* now send back TX status */
 	txi = IEEE80211_SKB_CB(skb);
-	link_id = hwsim_tx_cb(skb)->link_id;
+	tx_cb = *hwsim_tx_cb(skb);
 
 	ieee80211_tx_info_clear_status(txi);
 
@@ -6487,9 +6509,9 @@ static int hwsim_tx_info_frame_received_nl(struct sk_buff *skb_2,
 	txi->status.ack_signal = nla_get_u32(info->attrs[HWSIM_ATTR_SIGNAL]);
 
 	hdr = (struct ieee80211_hdr *)skb->data;
-	if (link_id >= 0) {
+	if (tx_cb.link_id >= 0) {
 		txi->status.link_valid = 1;
-		txi->status.link_id = link_id;
+		txi->status.link_id = tx_cb.link_id;
 	}
 
 	if (!(hwsim_flags & HWSIM_TX_CTL_NO_ACK) &&
@@ -6503,6 +6525,7 @@ static int hwsim_tx_info_frame_received_nl(struct sk_buff *skb_2,
 	if (hwsim_flags & HWSIM_TX_CTL_NO_ACK)
 		txi->flags |= IEEE80211_TX_STAT_NOACK_TRANSMITTED;
 
+	hwsim_tx_addrs_restore(skb, tx_cb.orig_addrs);
 	ieee80211_tx_status_irqsafe(data2->hw, skb);
 	return 0;
 out:
-- 
2.47.3