[PATCH wireless 1/2] wifi: mt76: mt7915: clear cipher state on key removal for WED offload

[Joshua Klinesmith <joshuaklinesmith@gmail.com>]

When switching from WPA-PSK/SAE to open/no encryption, the
DISABLE_KEY path never resets mvif->mt76.cipher back to zero.
The stale cipher value is sent to the WA firmware via BSS_INFO
updates, causing the firmware to keep the protection bit set on
WED-offloaded packets. The hardware then drops all plaintext
frames, resulting in zero throughput.

Reset mvif->mt76.cipher to zero and notify the firmware via
mt7915_mcu_add_bss_info() when the last group key is removed.

Fixes: 3fd2dbd6a1d3 ("mt76: mt7915: update bss_info with cipher after setting the group key")
Cc: stable@vger.kernel.org
Signed-off-by: Joshua Klinesmith <joshuaklinesmith@gmail.com>
---
 drivers/net/wireless/mediatek/mt76/mt7915/main.c | 14 +++++---------
 1 file changed, 5 insertions(+), 9 deletions(-)

diff --git a/drivers/net/wireless/mediatek/mt76/mt7915/main.c b/drivers/net/wireless/mediatek/mt76/mt7915/main.c
index fe0639c14b..8d32729a58 100644
--- a/drivers/net/wireless/mediatek/mt76/mt7915/main.c
+++ b/drivers/net/wireless/mediatek/mt76/mt7915/main.c
@@ -414,7 +414,11 @@ static int mt7915_set_key(struct ieee80211_hw *hw, enum set_key_cmd cmd,
 	} else {
 		if (idx == *wcid_keyidx)
 			*wcid_keyidx = -1;
-		goto out;
+
+		if (!sta && mvif->mt76.cipher) {
+			mvif->mt76.cipher = 0;
+			mt7915_mcu_add_bss_info(phy, vif, true);
+		}
 	}
 
 	mt76_wcid_key_setup(&dev->mt76, wcid, key);
@@ -486,10 +490,6 @@ static int mt7915_config(struct ieee80211_hw *hw, int radio_idx,
 		if (!enabled) {
 			rxfilter |= MT_WF_RFCR_DROP_OTHER_UC;
 			dev->monitor_mask &= ~BIT(band);
-		} else {
-			rxfilter &= ~MT_WF_RFCR_DROP_OTHER_UC;
-			dev->monitor_mask |= BIT(band);
-		}
 
 		mt76_rmw_field(dev, MT_DMA_DCR0(band), MT_DMA_DCR0_RXD_G5_EN,
 			       enabled);
@@ -1166,10 +1166,6 @@ static void mt7915_sta_statistics(struct ieee80211_hw *hw,
 	if (txrate->legacy || txrate->flags) {
 		if (txrate->legacy) {
 			sinfo->txrate.legacy = txrate->legacy;
-		} else {
-			sinfo->txrate.mcs = txrate->mcs;
-			sinfo->txrate.nss = txrate->nss;
-			sinfo->txrate.bw = txrate->bw;
 			sinfo->txrate.he_gi = txrate->he_gi;
 			sinfo->txrate.he_dcm = txrate->he_dcm;
 			sinfo->txrate.he_ru_alloc = txrate->he_ru_alloc;
-- 
2.43.0