[PATCH] Bluetooth: btmtkuart: fix a memleak in mtk_hci_wmt_sync

From: Dinghao Liu
Date: Wed Sep 22 2021 - 09:51:58 EST


bdev->evt_skb will get freed in the normal path and one error path
of mtk_hci_wmt_sync, while the other error paths do not free it,
which may cause a memleak. This bug is suggested by a static analysis
tool, please advise.

Fixes: e0b67035a90b ("Bluetooth: mediatek: update the common setup between MT7622 and other devices")
Signed-off-by: Dinghao Liu <dinghao.liu@xxxxxxxxxx>
---
drivers/bluetooth/btmtkuart.c | 13 ++++++++-----
1 file changed, 8 insertions(+), 5 deletions(-)

diff --git a/drivers/bluetooth/btmtkuart.c b/drivers/bluetooth/btmtkuart.c
index e9d91d7c0db4..9ba22b13b4fa 100644
--- a/drivers/bluetooth/btmtkuart.c
+++ b/drivers/bluetooth/btmtkuart.c
@@ -158,8 +158,10 @@ static int mtk_hci_wmt_sync(struct hci_dev *hdev,
int err;

hlen = sizeof(*hdr) + wmt_params->dlen;
- if (hlen > 255)
- return -EINVAL;
+ if (hlen > 255) {
+ err = -EINVAL;
+ goto err_free_skb;
+ }

hdr = (struct mtk_wmt_hdr *)&wc;
hdr->dir = 1;
@@ -173,7 +175,7 @@ static int mtk_hci_wmt_sync(struct hci_dev *hdev,
err = __hci_cmd_send(hdev, 0xfc6f, hlen, &wc);
if (err < 0) {
clear_bit(BTMTKUART_TX_WAIT_VND_EVT, &bdev->tx_state);
- return err;
+ goto err_free_skb;
}

/* The vendor specific WMT commands are all answered by a vendor
@@ -190,13 +192,14 @@ static int mtk_hci_wmt_sync(struct hci_dev *hdev,
if (err == -EINTR) {
bt_dev_err(hdev, "Execution of wmt command interrupted");
clear_bit(BTMTKUART_TX_WAIT_VND_EVT, &bdev->tx_state);
- return err;
+ goto err_free_skb;
}

if (err) {
bt_dev_err(hdev, "Execution of wmt command timed out");
clear_bit(BTMTKUART_TX_WAIT_VND_EVT, &bdev->tx_state);
- return -ETIMEDOUT;
+ err = -ETIMEDOUT;
+ goto err_free_skb;
}

/* Parse and handle the return WMT event */
--
2.17.1