wifi: ath10k: Fix memory leak in management tx

In the current logic, memory is allocated for storing the MSDU context
during management packet TX but this memory is not being freed during
management TX completion. Similar leaks are seen in the management TX
cleanup logic.

Kmemleak reports this problem as below,

unreferenced object 0xffffff80b64ed250 (size 16):
  comm "kworker/u16:7", pid 148, jiffies 4294687130 (age 714.199s)
  hex dump (first 16 bytes):
    00 2b d8 d8 80 ff ff ff c4 74 e9 fd 07 00 00 00  .+.......t......
  backtrace:
    [<ffffffe6e7b245dc>] __kmem_cache_alloc_node+0x1e4/0x2d8
    [<ffffffe6e7adde88>] kmalloc_trace+0x48/0x110
    [<ffffffe6bbd765fc>] ath10k_wmi_tlv_op_gen_mgmt_tx_send+0xd4/0x1d8 [ath10k_core]
    [<ffffffe6bbd3eed4>] ath10k_mgmt_over_wmi_tx_work+0x134/0x298 [ath10k_core]
    [<ffffffe6e78d5974>] process_scheduled_works+0x1ac/0x400
    [<ffffffe6e78d60b8>] worker_thread+0x208/0x328
    [<ffffffe6e78dc890>] kthread+0x100/0x1c0
    [<ffffffe6e78166c0>] ret_from_fork+0x10/0x20

Free the memory during completion and cleanup to fix the leak.

Protect the mgmt_pending_tx idr_remove() operation in
ath10k_wmi_tlv_op_cleanup_mgmt_tx_send() using ar->data_lock similar to
other instances.

Tested-on: WCN3990 hw1.0 SNOC WLAN.HL.2.0-01387-QCAHLSWMTPLZ-1

Fixes: dc40515 ("ath10k: handle mgmt tx completion event")
Fixes: c730c47 ("ath10k: Remove msdu from idr when management pkt send fails")
Cc: [email protected]
Signed-off-by: Manikanta Pubbisetty <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jeff Johnson <[email protected]>

Author: Manikanta Pubbisetty

drivers/net/wireless/ath/ath10k/wmi-tlv.c

@@ -3043,9 +3043,14 @@ ath10k_wmi_tlv_op_cleanup_mgmt_tx_send(struct ath10k *ar,
 				       struct sk_buff *msdu)
 {
 	struct ath10k_skb_cb *cb = ATH10K_SKB_CB(msdu);
+	struct ath10k_mgmt_tx_pkt_addr *pkt_addr;
 	struct ath10k_wmi *wmi = &ar->wmi;
 
-	idr_remove(&wmi->mgmt_pending_tx, cb->msdu_id);
+	spin_lock_bh(&ar->data_lock);
+	pkt_addr = idr_remove(&wmi->mgmt_pending_tx, cb->msdu_id);
+	spin_unlock_bh(&ar->data_lock);
+
+	kfree(pkt_addr);
 
 	return 0;
 }

drivers/net/wireless/ath/ath10k/wmi.c

@@ -2441,6 +2441,7 @@ wmi_process_mgmt_tx_comp(struct ath10k *ar, struct mgmt_tx_compl_params *param)
 	dma_unmap_single(ar->dev, pkt_addr->paddr,
 			 msdu->len, DMA_TO_DEVICE);
 	info = IEEE80211_SKB_CB(msdu);
+	kfree(pkt_addr);
 
 	if (param->status) {
 		info->flags &= ~IEEE80211_TX_STAT_ACK;
@@ -9612,6 +9613,7 @@ static int ath10k_wmi_mgmt_tx_clean_up_pending(int msdu_id, void *ptr,
 	dma_unmap_single(ar->dev, pkt_addr->paddr,
 			 msdu->len, DMA_TO_DEVICE);
 	ieee80211_free_txskb(ar->hw, msdu);
+	kfree(pkt_addr);
 
 	return 0;
 }