diff -up dhcp-4.2.5/common/lpf.c.vlan dhcp-4.2.5/common/lpf.c --- dhcp-4.2.5/common/lpf.c.vlan 2015-10-13 18:48:35.180447618 +0200 +++ dhcp-4.2.5/common/lpf.c 2015-10-13 18:51:29.797079032 +0200 @@ -521,6 +521,10 @@ ssize_t receive_packet (interface, buf, if (cmsg->cmsg_level == SOL_PACKET && cmsg->cmsg_type == PACKET_AUXDATA) { struct tpacket_auxdata *aux = (void *)CMSG_DATA(cmsg); + /* Discard packets with stripped vlan id */ + /* VLAN ID is only bottom 12-bits of TCI */ + if (aux->tp_vlan_tci & 0x0fff) + return 0; nocsum = aux->tp_status & TP_STATUS_CSUMNOTREADY; } }