[PATCH net-next 14/23] {topost} net: hns3: fix for use-after-free when setting ring parameter

From: Peng Li
Date: Wed Mar 07 2018 - 21:40:20 EST


From: Yunsheng Lin <linyunsheng@xxxxxxxxxx>

In hns3_set_ringparam, hns3_uninit_all_ring frees the
memory pointed by priv->ring_data[i].ring, and
hns3_change_all_ring_bd_num use that pointer without mallocing,
which will cause a use-after-free problem.

The patch fixes it by not freeing the memory in
hns3_uninit_all_ring, and uses hns3_put_ring_config to free it
when necessary.

Signed-off-by: Yunsheng Lin <linyunsheng@xxxxxxxxxx>
Signed-off-by: Peng Li <lipeng321@xxxxxxxxxx>
---
drivers/net/ethernet/hisilicon/hns3/hns3_enet.c | 10 +++++-----
1 file changed, 5 insertions(+), 5 deletions(-)

diff --git a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c
index f50245d..2bed73e 100644
--- a/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c
+++ b/drivers/net/ethernet/hisilicon/hns3/hns3_enet.c
@@ -2955,13 +2955,8 @@ int hns3_uninit_all_ring(struct hns3_nic_priv *priv)
h->ae_algo->ops->reset_queue(h, i);

hns3_fini_ring(priv->ring_data[i].ring);
- devm_kfree(priv->dev, priv->ring_data[i].ring);
hns3_fini_ring(priv->ring_data[i + h->kinfo.num_tqps].ring);
- devm_kfree(priv->dev,
- priv->ring_data[i + h->kinfo.num_tqps].ring);
}
- devm_kfree(priv->dev, priv->ring_data);
-
return 0;
}

@@ -3099,6 +3094,8 @@ static void hns3_client_uninit(struct hnae3_handle *handle, bool reset)
if (ret)
netdev_err(netdev, "uninit ring error\n");

+ hns3_put_ring_config(priv);
+
priv->ring_data = NULL;

free_netdev(netdev);
@@ -3304,6 +3301,8 @@ static int hns3_reset_notify_uninit_enet(struct hnae3_handle *handle)
if (ret)
netdev_err(netdev, "uninit ring error\n");

+ hns3_put_ring_config(priv);
+
priv->ring_data = NULL;

return ret;
@@ -3421,6 +3420,7 @@ int hns3_set_channels(struct net_device *netdev,
}

hns3_uninit_all_ring(priv);
+ hns3_put_ring_config(priv);

org_tqp_num = h->kinfo.num_tqps;
ret = hns3_modify_tqp_num(netdev, new_tqp_num);
--
2.9.3