[PATCH v2] wifi: ath10k: fix NULL pointer dereference in ath10k_wmi_tlv_op_pull_mgmt_tx_compl_ev()

[Xingyuan Mo]

We should check whether the WMI_TLV_TAG_STRUCT_MGMT_TX_COMPL_EVENT tlv is
present before accessing it, otherwise a null pointer deference error will
occur.

Fixes: dc405152bb64 ("ath10k: handle mgmt tx completion event")
Signed-off-by: Xingyuan Mo <hdth...@gmail.com>
---
Compared with the previous version, Signed-off-by and Fixes tags are added.

 drivers/net/wireless/ath/ath10k/wmi-tlv.c | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/drivers/net/wireless/ath/ath10k/wmi-tlv.c 
b/drivers/net/wireless/ath/ath10k/wmi-tlv.c
index 6b6aa3c36744..0ce08e9a0a3d 100644
--- a/drivers/net/wireless/ath/ath10k/wmi-tlv.c
+++ b/drivers/net/wireless/ath/ath10k/wmi-tlv.c
@@ -851,6 +851,10 @@ ath10k_wmi_tlv_op_pull_mgmt_tx_compl_ev(struct ath10k *ar, 
struct sk_buff *skb,
        }
 
        ev = tb[WMI_TLV_TAG_STRUCT_MGMT_TX_COMPL_EVENT];
+       if (!ev) {
+               kfree(tb);
+               return -EPROTO;
+       }
 
        arg->desc_id = ev->desc_id;
        arg->status = ev->status;
-- 
2.34.1