[PATCH 4.4 126/190] mwl8k: Fix a double Free in mwl8k_probe_hw

[Greg Kroah-Hartman]

From: Lv Yunlong <lyl2019@xxxxxxxxxxxxxxxx>

[ Upstream commit a8e083ee8e2a6c94c29733835adae8bf5b832748 ]

In mwl8k_probe_hw, hw->priv->txq is freed at the first time by
dma_free_coherent() in the call chain:
if(!priv->ap_fw)->mwl8k_init_txqs(hw)->mwl8k_txq_init(hw, i).

Then in err_free_queues of mwl8k_probe_hw, hw->priv->txq is freed
at the second time by mwl8k_txq_deinit(hw, i)->dma_free_coherent().

My patch set txq->txd to NULL after the first free to avoid the
double free.

Fixes: a66098daacee2 ("mwl8k: Marvell TOPDOG wireless driver")
Signed-off-by: Lv Yunlong <lyl2019@xxxxxxxxxxxxxxxx>
Signed-off-by: Kalle Valo <kvalo@xxxxxxxxxxxxxx>
Link: https://lore.kernel.org/r/20210402182627.4256-1-lyl2019@xxxxxxxxxxxxxxxx
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
 drivers/net/wireless/mwl8k.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/drivers/net/wireless/mwl8k.c b/drivers/net/wireless/mwl8k.c
index 088429d0a634..d448480b8406 100644
--- a/drivers/net/wireless/mwl8k.c
+++ b/drivers/net/wireless/mwl8k.c
@@ -1459,6 +1459,7 @@ static int mwl8k_txq_init(struct ieee80211_hw *hw, int index)
 	txq->skb = kcalloc(MWL8K_TX_DESCS, sizeof(*txq->skb), GFP_KERNEL);
 	if (txq->skb == NULL) {
 		pci_free_consistent(priv->pdev, size, txq->txd, txq->txd_dma);
+		txq->txd = NULL;
 		return -ENOMEM;
 	}
 
-- 
2.30.2