On 2021/2/3 11:13, Wenjia Zhao wrote:
> net: hns3: double free 'skb'
>
> The false branch of (tx_ret == NETDEV_TX_OK) free the skb. However, the
> kfree_skb(skb) in the out label will be execute when exits the function.
> So the skb has a double-free bugs.
>
> Remove the kfree_skb(skb) at line 269
The freeing is added by the below patch:
commit: 8f9eed1a8791("net: hns3: fix for skb leak when doing selftest")
which is to fix a skb leak problem.
kfree_skb(skb) in the out label corresponds to alloc_skb(),
and kfree_skb(skb) removed in this patch corresponds to
skb_get(skb) before calling hns3_nic_net_xmit() when
hns3_nic_net_xmit() non-NETDEV_TX_OK.
So I do not think there is double free 'skb' here, unless
I miss something here?
>
> Signed-off-by: Wenjia Zhao <driverfuzz...@gmail.com>
> ---
> drivers/net/ethernet/hisilicon/hns3/hns3_ethtool.c | 1 -
> 1 file changed, 1 deletion(-)
>
> diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3_ethtool.c
> b/drivers/net/ethernet/hisilicon/hns3/hns3_ethtool.c
> index 2622e04..1b926ff 100644
> --- a/drivers/net/ethernet/hisilicon/hns3/hns3_ethtool.c
> +++ b/drivers/net/ethernet/hisilicon/hns3/hns3_ethtool.c
> @@ -266,7 +266,6 @@ static int hns3_lp_run_test(struct net_device *ndev, enum
> hnae3_loop mode)
> if (tx_ret == NETDEV_TX_OK) {
> good_cnt++;
> } else {
> - kfree_skb(skb);
> netdev_err(ndev, "hns3_lb_run_test xmit failed: %d\n",
> tx_ret);
> }
>
