[PATCH v6 2/6] wifi: rtlwifi: rtl8192de: Fix low speed with WPA3-SAE

[Bitterblue Smith <rtl8821cerfe2@xxxxxxxxx>]

Some (all?) management frames are incorrectly reported to mac80211 as
decrypted when actually the hardware did not decrypt them. This results
in speeds 3-5 times lower than expected, 20-30 Mbps instead of 100
Mbps.

Fix this by checking the encryption type field of the RX descriptor.
rtw88 does the same thing.

This fix was tested only with rtl8192du, which will use the same code.

Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Bitterblue Smith <rtl8821cerfe2@xxxxxxxxx>
---
v6:
 - No change.

v5:
 - No change.

v4:
 - Patch is new in v4.
---
 .../net/wireless/realtek/rtlwifi/rtl8192de/trx.c   |  5 ++---
 .../net/wireless/realtek/rtlwifi/rtl8192de/trx.h   | 14 ++++++++++++++
 2 files changed, 16 insertions(+), 3 deletions(-)

diff --git a/drivers/net/wireless/realtek/rtlwifi/rtl8192de/trx.c b/drivers/net/wireless/realtek/rtlwifi/rtl8192de/trx.c
index 192982ec8152..30b262c3f6d0 100644
--- a/drivers/net/wireless/realtek/rtlwifi/rtl8192de/trx.c
+++ b/drivers/net/wireless/realtek/rtlwifi/rtl8192de/trx.c
@@ -413,7 +413,8 @@ bool rtl92de_rx_query_desc(struct ieee80211_hw *hw,	struct rtl_stats *stats,
 	stats->icv = (u16)get_rx_desc_icv(pdesc);
 	stats->crc = (u16)get_rx_desc_crc32(pdesc);
 	stats->hwerror = (stats->crc | stats->icv);
-	stats->decrypted = !get_rx_desc_swdec(pdesc);
+	stats->decrypted = !get_rx_desc_swdec(pdesc) &&
+			   get_rx_desc_enc_type(pdesc) != RX_DESC_ENC_NONE;
 	stats->rate = (u8)get_rx_desc_rxmcs(pdesc);
 	stats->shortpreamble = (u16)get_rx_desc_splcp(pdesc);
 	stats->isampdu = (bool)(get_rx_desc_paggr(pdesc) == 1);
@@ -426,8 +427,6 @@ bool rtl92de_rx_query_desc(struct ieee80211_hw *hw,	struct rtl_stats *stats,
 	rx_status->band = hw->conf.chandef.chan->band;
 	if (get_rx_desc_crc32(pdesc))
 		rx_status->flag |= RX_FLAG_FAILED_FCS_CRC;
-	if (!get_rx_desc_swdec(pdesc))
-		rx_status->flag |= RX_FLAG_DECRYPTED;
 	if (get_rx_desc_bw(pdesc))
 		rx_status->bw = RATE_INFO_BW_40;
 	if (get_rx_desc_rxht(pdesc))
diff --git a/drivers/net/wireless/realtek/rtlwifi/rtl8192de/trx.h b/drivers/net/wireless/realtek/rtlwifi/rtl8192de/trx.h
index 2992668c156c..f189ee2d9be2 100644
--- a/drivers/net/wireless/realtek/rtlwifi/rtl8192de/trx.h
+++ b/drivers/net/wireless/realtek/rtlwifi/rtl8192de/trx.h
@@ -14,6 +14,15 @@
 #define USB_HWDESC_HEADER_LEN			32
 #define CRCLENGTH				4
 
+enum rtl92d_rx_desc_enc {
+	RX_DESC_ENC_NONE	= 0,
+	RX_DESC_ENC_WEP40	= 1,
+	RX_DESC_ENC_TKIP_WO_MIC	= 2,
+	RX_DESC_ENC_TKIP_MIC	= 3,
+	RX_DESC_ENC_AES		= 4,
+	RX_DESC_ENC_WEP104	= 5,
+};
+
 /* macros to read/write various fields in RX or TX descriptors */
 
 static inline void set_tx_desc_pkt_size(__le32 *__pdesc, u32 __val)
@@ -246,6 +255,11 @@ static inline u32 get_rx_desc_drv_info_size(__le32 *__pdesc)
 	return le32_get_bits(*__pdesc, GENMASK(19, 16));
 }
 
+static inline u32 get_rx_desc_enc_type(__le32 *__pdesc)
+{
+	return le32_get_bits(*__pdesc, GENMASK(22, 20));
+}
+
 static inline u32 get_rx_desc_shift(__le32 *__pdesc)
 {
 	return le32_get_bits(*__pdesc, GENMASK(25, 24));
-- 
2.44.0