[PATCH v2 2/5] wifi: ath11k: avoid IDR mutation during pending mgmt TX cleanup

[Jiale Yao]

The pending management TX cleanup walks txmgmt_idr with idr_for_each(),
and its callback removes the current entry. This can invalidate the
radix-tree iterator retained by idr_for_each().

Use idr_for_each_entry() so every iteration starts with a fresh lookup.
Continue to remove each entry under txmgmt_idr_lock before freeing its skb,
preventing concurrent TX completion from finding a stale skb pointer.

Fixes: d5c65159f289 ("ath11k: driver for Qualcomm IEEE 802.11ax devices")
Signed-off-by: Jiale Yao <yaojiale02 at 163.com>
---
 drivers/net/wireless/ath/ath11k/core.c |  3 +--
 drivers/net/wireless/ath/ath11k/mac.c  | 12 ++++++------
 drivers/net/wireless/ath/ath11k/mac.h  |  2 +-
 3 files changed, 8 insertions(+), 9 deletions(-)

diff --git a/drivers/net/wireless/ath/ath11k/core.c b/drivers/net/wireless/ath/ath11k/core.c
index 8039124e7832..31ac17c51036 100644
--- a/drivers/net/wireless/ath/ath11k/core.c
+++ b/drivers/net/wireless/ath/ath11k/core.c
@@ -2449,8 +2449,7 @@ void ath11k_core_pre_reconfigure_recovery(struct ath11k_base *ab)
 		complete(&ar->thermal.wmi_sync);
 
 		wake_up(&ar->dp.tx_empty_waitq);
-		idr_for_each(&ar->txmgmt_idr,
-			     ath11k_mac_tx_mgmt_pending_free, ar);
+		ath11k_mac_tx_mgmt_pending_free(ar);
 		idr_destroy(&ar->txmgmt_idr);
 		wake_up(&ar->txmgmt_empty_waitq);
 
diff --git a/drivers/net/wireless/ath/ath11k/mac.c b/drivers/net/wireless/ath/ath11k/mac.c
index ae91b57c8422..f9af403a2f0d 100644
--- a/drivers/net/wireless/ath/ath11k/mac.c
+++ b/drivers/net/wireless/ath/ath11k/mac.c
@@ -6167,13 +6167,13 @@ static void ath11k_mac_tx_mgmt_free(struct ath11k *ar, int buf_id)
 	ath11k_mgmt_over_wmi_tx_drop(ar, msdu);
 }
 
-int ath11k_mac_tx_mgmt_pending_free(int buf_id, void *skb, void *ctx)
+void ath11k_mac_tx_mgmt_pending_free(struct ath11k *ar)
 {
-	struct ath11k *ar = ctx;
-
-	ath11k_mac_tx_mgmt_free(ar, buf_id);
+	struct sk_buff *msdu;
+	int buf_id;
 
-	return 0;
+	idr_for_each_entry(&ar->txmgmt_idr, msdu, buf_id)
+		ath11k_mac_tx_mgmt_free(ar, buf_id);
 }
 
 static int ath11k_mac_vif_txmgmt_idr_remove(int buf_id, void *skb, void *ctx)
@@ -10417,7 +10417,7 @@ static void __ath11k_mac_unregister(struct ath11k *ar)
 
 	ieee80211_unregister_hw(ar->hw);
 
-	idr_for_each(&ar->txmgmt_idr, ath11k_mac_tx_mgmt_pending_free, ar);
+	ath11k_mac_tx_mgmt_pending_free(ar);
 	idr_destroy(&ar->txmgmt_idr);
 
 	kfree(ar->mac.sbands[NL80211_BAND_2GHZ].channels);
diff --git a/drivers/net/wireless/ath/ath11k/mac.h b/drivers/net/wireless/ath/ath11k/mac.h
index 59f83c7175fd..127cb476b44b 100644
--- a/drivers/net/wireless/ath/ath11k/mac.h
+++ b/drivers/net/wireless/ath/ath11k/mac.h
@@ -162,7 +162,7 @@ struct ath11k *ath11k_mac_get_ar_by_pdev_id(struct ath11k_base *ab, u32 pdev_id)
 
 void ath11k_mac_drain_tx(struct ath11k *ar);
 void ath11k_mac_peer_cleanup_all(struct ath11k *ar);
-int ath11k_mac_tx_mgmt_pending_free(int buf_id, void *skb, void *ctx);
+void ath11k_mac_tx_mgmt_pending_free(struct ath11k *ar);
 u8 ath11k_mac_bw_to_mac80211_bw(u8 bw);
 enum nl80211_he_gi ath11k_mac_he_gi_to_nl80211_he_gi(u8 sgi);
 enum nl80211_he_ru_alloc ath11k_mac_phy_he_ru_to_nl80211_he_ru_alloc(u16 ru_phy);
-- 
2.34.1