A denial of service (DoS) attack was found in the mlx5 driver in the Linux kernel. A KVM guest VM using virtio-net can crash the host by sending a short packet, for example, size < ETH_HLEN. The packet may traverse through vhost-net, macvtap, and vlan without any validation or drop. When this packet is presented to the mlx5 driver on the host side, the kernel panic happens since mlx5_core assumes the frame size is always >= ETH_HLEN.