From c186dd147a56840427f7623bfe7073496ac115bb Mon Sep 17 00:00:00 2001
From: Ksawlii <ksawery.blaszczak@proton.me>
Date: Sun, 24 Nov 2024 00:23:53 +0100
Subject: [PATCH] Revert "wifi: mac80211: fix BA session teardown race"

This reverts commit a2036d5d3c877e35b3418b28074b49236702d8c3.
---
 net/mac80211/agg-tx.c     |  6 +++++-
 net/mac80211/driver-ops.c |  3 +++
 net/mac80211/sta_info.c   | 14 --------------
 3 files changed, 8 insertions(+), 15 deletions(-)

diff --git a/net/mac80211/agg-tx.c b/net/mac80211/agg-tx.c
index 4b4ab1961..92e5812da 100755
--- a/net/mac80211/agg-tx.c
+++ b/net/mac80211/agg-tx.c
@@ -491,7 +491,7 @@ void ieee80211_tx_ba_session_handle_start(struct sta_info *sta, int tid)
 {
 	struct tid_ampdu_tx *tid_tx;
 	struct ieee80211_local *local = sta->local;
-	struct ieee80211_sub_if_data *sdata = sta->sdata;
+	struct ieee80211_sub_if_data *sdata;
 	struct ieee80211_ampdu_params params = {
 		.sta = &sta->sta,
 		.action = IEEE80211_AMPDU_TX_START,
@@ -521,6 +521,7 @@ void ieee80211_tx_ba_session_handle_start(struct sta_info *sta, int tid)
 	 */
 	synchronize_net();
 
+	sdata = sta->sdata;
 	params.ssn = sta->tid_seq[tid] >> 4;
 	ret = drv_ampdu_action(local, sdata, &params);
 	tid_tx->ssn = params.ssn;
@@ -534,6 +535,9 @@ void ieee80211_tx_ba_session_handle_start(struct sta_info *sta, int tid)
 		 */
 		set_bit(HT_AGG_STATE_DRV_READY, &tid_tx->state);
 	} else if (ret) {
+		if (!sdata)
+			return;
+
 		ht_dbg(sdata,
 		       "BA request denied - HW unavailable for %pM tid %d\n",
 		       sta->sta.addr, tid);
diff --git a/net/mac80211/driver-ops.c b/net/mac80211/driver-ops.c
index 48322e45e..120bd9cdf 100755
--- a/net/mac80211/driver-ops.c
+++ b/net/mac80211/driver-ops.c
@@ -331,6 +331,9 @@ int drv_ampdu_action(struct ieee80211_local *local,
 
 	might_sleep();
 
+	if (!sdata)
+		return -EIO;
+
 	sdata = get_bss_sdata(sdata);
 	if (!check_sdata_in_driver(sdata))
 		return -EIO;
diff --git a/net/mac80211/sta_info.c b/net/mac80211/sta_info.c
index 3bb7a3314..f7637176d 100755
--- a/net/mac80211/sta_info.c
+++ b/net/mac80211/sta_info.c
@@ -1064,20 +1064,6 @@ static void __sta_info_destroy_part2(struct sta_info *sta)
 	 *	 after _part1 and before _part2!
 	 */
 
-	/*
-	 * There's a potential race in _part1 where we set WLAN_STA_BLOCK_BA
-	 * but someone might have just gotten past a check, and not yet into
-	 * queuing the work/creating the data/etc.
-	 *
-	 * Do another round of destruction so that the worker is certainly
-	 * canceled before we later free the station.
-	 *
-	 * Since this is after synchronize_rcu()/synchronize_net() we're now
-	 * certain that nobody can actually hold a reference to the STA and
-	 * be calling e.g. ieee80211_start_tx_ba_session().
-	 */
-	ieee80211_sta_tear_down_BA_sessions(sta, AGG_STOP_DESTROY_STA);
-
 	might_sleep();
 	lockdep_assert_held(&local->sta_mtx);