[PATCH] wifi: mac80211: don't use rate mask for scanning

[Johannes Berg <johannes@sipsolutions.net>]

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

The rate mask is intended for use during operation, and
can be set to only have masks for the currently active
band. As such, it cannot be used for scanning which can
be on other bands as well.

Simply ignore the rate masks during scanning to avoid
warnings from incorrect settings.

Reported-by: syzbot+fdc5123366fb9c3fdc6d@syzkaller.appspotmail.com
Closes: https://syzkaller.appspot.com/bug?extid=fdc5123366fb9c3fdc6d
Co-developed-by: Dmitry Antipov <dmantipov@yandex.ru>
Signed-off-by: Dmitry Antipov <dmantipov@yandex.ru>
Signed-off-by: Johannes Berg <johannes.berg@intel.com>
---
 include/net/mac80211.h |  3 +++
 net/mac80211/rate.c    |  6 +++++-
 net/mac80211/scan.c    |  1 +
 net/mac80211/tx.c      | 13 +++++++++----
 4 files changed, 18 insertions(+), 5 deletions(-)

diff --git a/include/net/mac80211.h b/include/net/mac80211.h
index 353488ab94a2..2d7f87bc5324 100644
--- a/include/net/mac80211.h
+++ b/include/net/mac80211.h
@@ -953,6 +953,8 @@ enum mac80211_tx_info_flags {
  *	of their QoS TID or other priority field values.
  * @IEEE80211_TX_CTRL_MCAST_MLO_FIRST_TX: first MLO TX, used mostly internally
  *	for sequence number assignment
+ * @IEEE80211_TX_CTRL_SCAN_TX: Indicates that this frame is transmitted
+ *	due to scanning, not in normal operation on the interface.
  * @IEEE80211_TX_CTRL_MLO_LINK: If not @IEEE80211_LINK_UNSPECIFIED, this
  *	frame should be transmitted on the specific link. This really is
  *	only relevant for frames that do not have data present, and is
@@ -973,6 +975,7 @@ enum mac80211_tx_control_flags {
 	IEEE80211_TX_CTRL_NO_SEQNO		= BIT(7),
 	IEEE80211_TX_CTRL_DONT_REORDER		= BIT(8),
 	IEEE80211_TX_CTRL_MCAST_MLO_FIRST_TX	= BIT(9),
+	IEEE80211_TX_CTRL_SCAN_TX		= BIT(10),
 	IEEE80211_TX_CTRL_MLO_LINK		= 0xf0000000,
 };
 
diff --git a/net/mac80211/rate.c b/net/mac80211/rate.c
index 23404b275457..4dc1def69548 100644
--- a/net/mac80211/rate.c
+++ b/net/mac80211/rate.c
@@ -877,6 +877,7 @@ void ieee80211_get_tx_rates(struct ieee80211_vif *vif,
 	struct ieee80211_sub_if_data *sdata;
 	struct ieee80211_tx_info *info = IEEE80211_SKB_CB(skb);
 	struct ieee80211_supported_band *sband;
+	u32 mask = ~0;
 
 	rate_control_fill_sta_table(sta, info, dest, max_rates);
 
@@ -889,9 +890,12 @@ void ieee80211_get_tx_rates(struct ieee80211_vif *vif,
 	if (ieee80211_is_tx_data(skb))
 		rate_control_apply_mask(sdata, sta, sband, dest, max_rates);
 
+	if (!(info->control.flags & IEEE80211_TX_CTRL_SCAN_TX))
+		mask = sdata->rc_rateidx_mask[info->band];
+
 	if (dest[0].idx < 0)
 		__rate_control_send_low(&sdata->local->hw, sband, sta, info,
-					sdata->rc_rateidx_mask[info->band]);
+					mask);
 
 	if (sta)
 		rate_fixup_ratelist(vif, sband, info, dest, max_rates);
diff --git a/net/mac80211/scan.c b/net/mac80211/scan.c
index 0429e59ba387..73850312580f 100644
--- a/net/mac80211/scan.c
+++ b/net/mac80211/scan.c
@@ -648,6 +648,7 @@ static void ieee80211_send_scan_probe_req(struct ieee80211_sub_if_data *sdata,
 				cpu_to_le16(IEEE80211_SN_TO_SEQ(sn));
 		}
 		IEEE80211_SKB_CB(skb)->flags |= tx_flags;
+		IEEE80211_SKB_CB(skb)->control.flags |= IEEE80211_TX_CTRL_SCAN_TX;
 		ieee80211_tx_skb_tid_band(sdata, skb, 7, channel->band);
 	}
 }
diff --git a/net/mac80211/tx.c b/net/mac80211/tx.c
index 6bf223e6cd1a..cfd0a62d0152 100644
--- a/net/mac80211/tx.c
+++ b/net/mac80211/tx.c
@@ -698,11 +698,16 @@ ieee80211_tx_h_rate_ctrl(struct ieee80211_tx_data *tx)
 	txrc.bss_conf = &tx->sdata->vif.bss_conf;
 	txrc.skb = tx->skb;
 	txrc.reported_rate.idx = -1;
-	txrc.rate_idx_mask = tx->sdata->rc_rateidx_mask[info->band];
 
-	if (tx->sdata->rc_has_mcs_mask[info->band])
-		txrc.rate_idx_mcs_mask =
-			tx->sdata->rc_rateidx_mcs_mask[info->band];
+	if (unlikely(info->control.flags & IEEE80211_TX_CTRL_SCAN_TX)) {
+		txrc.rate_idx_mask = ~0;
+	} else {
+		txrc.rate_idx_mask = tx->sdata->rc_rateidx_mask[info->band];
+
+		if (tx->sdata->rc_has_mcs_mask[info->band])
+			txrc.rate_idx_mcs_mask =
+				tx->sdata->rc_rateidx_mcs_mask[info->band];
+	}
 
 	txrc.bss = (tx->sdata->vif.type == NL80211_IFTYPE_AP ||
 		    tx->sdata->vif.type == NL80211_IFTYPE_MESH_POINT ||
-- 
2.44.0