In drivers/net/ethernet/hisilicon/hns/hns_enet.c in the Linux kernel before 4.13, local users can cause a denial of service (use-after-free and BUG) or possibly have unspecified other impact by leveraging differences in skb handling between hns_nic_net_xmit_hw and hns_nic_net_xmit.
https://www.debian.org/security/2018/dsa-4188
https://github.com/torvalds/linux/commit/27463ad99f738ed93c7c8b3e2e5bc8c4853a2ff2