[PATCH ath-next] wifi: ath12k: Add fallback for invalid channel number in PHY metadata

[Aishwarya R]

From: Sriram R <quic_srirrama at quicinc.com>

Currently, ath12k_dp_rx_h_ppdu() determines the band and frequency
based on the channel number and center frequency from the RX descriptor's
PHY metadata. However, in rare cases, it is observed that frequency
retrieved from the metadata may be invalid or unexpected especially for
6 GHz frames.
This can result in a NULL sband, which prevents proper frequency assignment
in rx_status and potentially leading to incorrect RX packet classification.

To fix this potential issue, add a fallback mechanism that uses
ar->rx_channel to populate the band and frequency when the derived
sband is invalid or missing.

Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.4.1-00199-QCAHKSWPL_SILICONZ-1

Fixes: d889913205cf ("wifi: ath12k: driver for Qualcomm Wi-Fi 7 devices")
Signed-off-by: Sriram R <quic_srirrama at quicinc.com>
Co-developed-by: Vinith Kumar R <quic_vinithku at quicinc.com>
Signed-off-by: Vinith Kumar R <quic_vinithku at quicinc.com>
Signed-off-by: Aishwarya R <aishwarya.r at oss.qualcomm.com>
---
 drivers/net/wireless/ath/ath12k/dp_rx.c | 16 +++++++++++++++-
 1 file changed, 15 insertions(+), 1 deletion(-)

diff --git a/drivers/net/wireless/ath/ath12k/dp_rx.c b/drivers/net/wireless/ath/ath12k/dp_rx.c
index 8ab91273592c..adb0cfe109e6 100644
--- a/drivers/net/wireless/ath/ath12k/dp_rx.c
+++ b/drivers/net/wireless/ath/ath12k/dp_rx.c
@@ -2533,6 +2533,8 @@ void ath12k_dp_rx_h_ppdu(struct ath12k *ar, struct ath12k_dp_rx_info *rx_info)
 	channel_num = meta_data;
 	center_freq = meta_data >> 16;
 
+	rx_status->band = NUM_NL80211_BANDS;
+
 	if (center_freq >= ATH12K_MIN_6GHZ_FREQ &&
 	    center_freq <= ATH12K_MAX_6GHZ_FREQ) {
 		rx_status->band = NL80211_BAND_6GHZ;
@@ -2541,21 +2543,33 @@ void ath12k_dp_rx_h_ppdu(struct ath12k *ar, struct ath12k_dp_rx_info *rx_info)
 		rx_status->band = NL80211_BAND_2GHZ;
 	} else if (channel_num >= 36 && channel_num <= 173) {
 		rx_status->band = NL80211_BAND_5GHZ;
-	} else {
+	}
+
+	if (unlikely(rx_status->band == NUM_NL80211_BANDS ||
+		     !ath12k_ar_to_hw(ar)->wiphy->bands[rx_status->band])) {
+		ath12k_warn(ar->ab, "sband is NULL for status band %d channel_num %d center_freq %d pdev_id %d\n",
+			    rx_status->band, channel_num, center_freq, ar->pdev_idx);
+
 		spin_lock_bh(&ar->data_lock);
 		channel = ar->rx_channel;
 		if (channel) {
 			rx_status->band = channel->band;
 			channel_num =
 				ieee80211_frequency_to_channel(channel->center_freq);
+			rx_status->freq = ieee80211_channel_to_frequency(channel_num,
+									 rx_status->band);
+		} else {
+			ath12k_err(ar->ab, "unable to determine channel, band for rx packet");
 		}
 		spin_unlock_bh(&ar->data_lock);
+		goto h_rate;
 	}
 
 	if (rx_status->band != NL80211_BAND_6GHZ)
 		rx_status->freq = ieee80211_channel_to_frequency(channel_num,
 								 rx_status->band);
 
+h_rate:
 	ath12k_dp_rx_h_rate(ar, rx_info);
 }

base-commit: 708243c62efde8241e2c66e9c3f377658855149d 
-- 
2.34.1