[PATCH v2 2/2] wifi: cfg80211: derive S1G beacon TSF from S1G fields

[Zhao Li <enderaoelyther@gmail.com>]

cfg80211_inform_bss_frame_data() parses S1G beacons with the extension
frame layout, but still reads the TSF from the regular probe response
layout after the S1G branch. For S1G beacons that reads bytes at the
regular management-frame timestamp offset instead of the S1G timestamp.

Use the 32-bit S1G beacon timestamp and the S1G Beacon Compatibility
element's TSF completion field when informing an S1G BSS. Keep the
regular management-frame timestamp read in the non-S1G branch.

Fixes: 9eaffe5078ca ("cfg80211: convert S1G beacon to scan results")
Cc: stable@vger.kernel.org
Signed-off-by: Zhao Li <enderaoelyther@gmail.com>
---
 net/wireless/scan.c | 5 +++--
 1 file changed, 3 insertions(+), 2 deletions(-)

diff --git a/net/wireless/scan.c b/net/wireless/scan.c
index 27a56ee2e8f0b..c90619eeb03b1 100644
--- a/net/wireless/scan.c
+++ b/net/wireless/scan.c
@@ -3309,14 +3309,15 @@ cfg80211_inform_bss_frame_data(struct wiphy *wiphy,
 		bssid = ext->u.s1g_beacon.sa;
 		capability = le16_to_cpu(compat->compat_info);
 		beacon_interval = le16_to_cpu(compat->beacon_int);
+		tsf = le32_to_cpu(ext->u.s1g_beacon.timestamp);
+		tsf |= (u64)le32_to_cpu(compat->tsf_completion) << 32;
 	} else {
 		bssid = mgmt->bssid;
 		beacon_interval = le16_to_cpu(mgmt->u.probe_resp.beacon_int);
 		capability = le16_to_cpu(mgmt->u.probe_resp.capab_info);
+		tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp);
 	}
 
-	tsf = le64_to_cpu(mgmt->u.probe_resp.timestamp);
-
 	if (ieee80211_is_probe_resp(mgmt->frame_control))
 		ftype = CFG80211_BSS_FTYPE_PRESP;
 	else if (ext)
-- 
2.50.1 (Apple Git-155)