wifi: ath12k: Pass ab pointer directly to ath12k_dp_tx_get_encap_type()

[ Upstream commit 0506283 ]

In ath12k_dp_tx_get_encap_type(), the arvif parameter is only used to
retrieve the ab pointer. In vdev delete sequence the arvif->ar could
become NULL and that would trigger kernel panic.
Since the caller ath12k_dp_tx() already has a valid ab pointer, pass it
directly to avoid panic and unnecessary dereferencing.

PC points to "ath12k_dp_tx+0x228/0x988 [ath12k]"
LR points to "ath12k_dp_tx+0xc8/0x988 [ath12k]".
The Backtrace obtained is as follows:
ath12k_dp_tx+0x228/0x988 [ath12k]
ath12k_mac_tx_check_max_limit+0x608/0x920 [ath12k]
ieee80211_process_measurement_req+0x320/0x348 [mac80211]
ieee80211_tx_dequeue+0x9ac/0x1518 [mac80211]
ieee80211_tx_dequeue+0xb14/0x1518 [mac80211]
ieee80211_tx_prepare_skb+0x224/0x254 [mac80211]
ieee80211_xmit+0xec/0x100 [mac80211]
__ieee80211_subif_start_xmit+0xc50/0xf40 [mac80211]
ieee80211_subif_start_xmit+0x2e8/0x308 [mac80211]
netdev_start_xmit+0x150/0x18c
dev_hard_start_xmit+0x74/0xc0

Tested-on: QCN9274 hw2.0 PCI WLAN.WBE.1.3.1-00173-QCAHKSWPL_SILICONZ-1

Fixes: e93bbd6 ("wifi: ath12k: fix packets are sent in native wifi mode while we set raw mode")
Signed-off-by: Tamizh Chelvam Raja <[email protected]>
Reviewed-by: Vasanthakumar Thiagarajan <[email protected]>
Link: https://patch.msgid.link/[email protected]
Signed-off-by: Jeff Johnson <[email protected]>
Signed-off-by: Sasha Levin <[email protected]>

Author: Tamizh Chelvam Raja

drivers/net/wireless/ath/ath12k/dp_tx.c

@@ -13,10 +13,9 @@
 #include "mac.h"
 
 static enum hal_tcl_encap_type
-ath12k_dp_tx_get_encap_type(struct ath12k_link_vif *arvif, struct sk_buff *skb)
+ath12k_dp_tx_get_encap_type(struct ath12k_base *ab, struct sk_buff *skb)
 {
 	struct ieee80211_tx_info *tx_info = IEEE80211_SKB_CB(skb);
-	struct ath12k_base *ab = arvif->ar->ab;
 
 	if (test_bit(ATH12K_FLAG_RAW_MODE, &ab->dev_flags))
 		return HAL_TCL_ENCAP_TYPE_RAW;
@@ -305,7 +304,7 @@ int ath12k_dp_tx(struct ath12k *ar, struct ath12k_link_vif *arvif,
 			u32_encode_bits(mcbc_gsn, HTT_TCL_META_DATA_GLOBAL_SEQ_NUM);
 	}
 
-	ti.encap_type = ath12k_dp_tx_get_encap_type(arvif, skb);
+	ti.encap_type = ath12k_dp_tx_get_encap_type(ab, skb);
 	ti.addr_search_flags = arvif->hal_addr_search_flags;
 	ti.search_type = arvif->search_type;
 	ti.type = HAL_TCL_DESC_TYPE_BUFFER;