[PATCH 5/5] wifi: ath12k: avoid IDR mutation during vif mgmt TX cleanup

[Jiale Yao]

ath12k_mac_vdev_delete() walks txmgmt_idr with idr_for_each(), and its
callback removes each entry belonging to the interface. Removing the
current entry can invalidate the radix-tree iterator retained by
idr_for_each().

Move the walk into a helper that uses idr_for_each_entry(). It performs a
fresh lookup for every iteration, so each matching entry can be removed
through the locked removal helper without retaining iterator state across
the removal.

Fixes: d889913205cf ("wifi: ath12k: driver for Qualcomm Wi-Fi 7 devices")
Signed-off-by: Jiale Yao <yaojiale02 at 163.com>
---
 drivers/net/wireless/ath/ath12k/mac.c | 21 +++++++++++----------
 1 file changed, 11 insertions(+), 10 deletions(-)

diff --git a/drivers/net/wireless/ath/ath12k/mac.c b/drivers/net/wireless/ath/ath12k/mac.c
index 7695b21149d1..ba41b0fa728e 100644
--- a/drivers/net/wireless/ath/ath12k/mac.c
+++ b/drivers/net/wireless/ath/ath12k/mac.c
@@ -9201,16 +9201,18 @@ int ath12k_mac_tx_mgmt_pending_free(int buf_id, void *skb, void *ctx)
 	return 0;
 }
 
-static int ath12k_mac_vif_txmgmt_idr_remove(int buf_id, void *skb, void *ctx)
+static void ath12k_mac_vif_txmgmt_cleanup(struct ath12k *ar,
+					  struct ieee80211_vif *vif)
 {
-	struct ieee80211_vif *vif = ctx;
-	struct ath12k_skb_cb *skb_cb = ATH12K_SKB_CB(skb);
-	struct ath12k *ar = skb_cb->ar;
-
-	if (skb_cb->vif == vif)
-		ath12k_mac_tx_mgmt_free(ar, buf_id);
+	struct ath12k_skb_cb *skb_cb;
+	struct sk_buff *skb;
+	int buf_id;
 
-	return 0;
+	idr_for_each_entry(&ar->txmgmt_idr, skb, buf_id) {
+		skb_cb = ATH12K_SKB_CB(skb);
+		if (skb_cb->vif == vif)
+			ath12k_mac_tx_mgmt_free(ar, buf_id);
+	}
 }
 
 static int ath12k_mac_mgmt_tx_wmi(struct ath12k *ar, struct ath12k_link_vif *arvif,
@@ -10972,8 +10974,7 @@ static int ath12k_mac_vdev_delete(struct ath12k *ar, struct ath12k_link_vif *arv
 	ath12k_peer_cleanup(ar, arvif->vdev_id);
 	ath12k_ahvif_put_link_cache(ahvif, arvif->link_id);
 
-	idr_for_each(&ar->txmgmt_idr,
-		     ath12k_mac_vif_txmgmt_idr_remove, vif);
+	ath12k_mac_vif_txmgmt_cleanup(ar, vif);
 
 	ath12k_mac_vif_unref(ath12k_ab_to_dp(ab), vif);
 
-- 
2.34.1