text: // autogenerated by syzkaller (https://github.com/google/syzkaller)
  
  #define _GNU_SOURCE
  
  #include <arpa/inet.h>
  #include <endian.h>
  #include <errno.h>
  #include <fcntl.h>
  #include <net/if.h>
  #include <net/if_arp.h>
  #include <netinet/in.h>
  #include <sched.h>
  #include <stdarg.h>
  #include <stdbool.h>
  #include <stdint.h>
  #include <stdio.h>
  #include <stdlib.h>
  #include <string.h>
  #include <sys/ioctl.h>
  #include <sys/mount.h>
  #include <sys/prctl.h>
  #include <sys/resource.h>
  #include <sys/socket.h>
  #include <sys/stat.h>
  #include <sys/syscall.h>
  #include <sys/time.h>
  #include <sys/types.h>
  #include <sys/uio.h>
  #include <sys/wait.h>
  #include <unistd.h>
  
  #include <linux/capability.h>
  #include <linux/genetlink.h>
  #include <linux/if_addr.h>
  #include <linux/if_ether.h>
  #include <linux/if_link.h>
  #include <linux/if_tun.h>
  #include <linux/in6.h>
  #include <linux/ip.h>
  #include <linux/neighbour.h>
  #include <linux/net.h>
  #include <linux/netlink.h>
  #include <linux/rtnetlink.h>
  #include <linux/tcp.h>
  #include <linux/veth.h>
  
  unsigned long long procid;
  
  static bool write_file(const char* file, const char* what, ...)
  {
    char buf[1024];
    va_list args;
    va_start(args, what);
    vsnprintf(buf, sizeof(buf), what, args);
    va_end(args);
    buf[sizeof(buf) - 1] = 0;
    int len = strlen(buf);
    int fd = open(file, O_WRONLY | O_CLOEXEC);
    if (fd == -1)
      return false;
    if (write(fd, buf, len) != len) {
      int err = errno;
      close(fd);
      errno = err;
      return false;
    }
    close(fd);
    return true;
  }
  
  struct nlmsg {
    char* pos;
    int nesting;
    struct nlattr* nested[8];
    char buf[1024];
  };
  
  static struct nlmsg nlmsg;
  
  static void netlink_init(struct nlmsg* nlmsg, int typ, int flags,
                           const void* data, int size)
  {
    memset(nlmsg, 0, sizeof(*nlmsg));
    struct nlmsghdr* hdr = (struct nlmsghdr*)nlmsg->buf;
    hdr->nlmsg_type = typ;
    hdr->nlmsg_flags = NLM_F_REQUEST | NLM_F_ACK | flags;
    memcpy(hdr + 1, data, size);
    nlmsg->pos = (char*)(hdr + 1) + NLMSG_ALIGN(size);
  }
  
  static void netlink_attr(struct nlmsg* nlmsg, int typ, const void* data,
                           int size)
  {
    struct nlattr* attr = (struct nlattr*)nlmsg->pos;
    attr->nla_len = sizeof(*attr) + size;
    attr->nla_type = typ;
    memcpy(attr + 1, data, size);
    nlmsg->pos += NLMSG_ALIGN(attr->nla_len);
  }
  
  static void netlink_nest(struct nlmsg* nlmsg, int typ)
  {
    struct nlattr* attr = (struct nlattr*)nlmsg->pos;
    attr->nla_type = typ;
    nlmsg->pos += sizeof(*attr);
    nlmsg->nested[nlmsg->nesting++] = attr;
  }
  
  static void netlink_done(struct nlmsg* nlmsg)
  {
    struct nlattr* attr = nlmsg->nested[--nlmsg->nesting];
    attr->nla_len = nlmsg->pos - (char*)attr;
  }
  
  static int netlink_send_ext(struct nlmsg* nlmsg, int sock, uint16_t reply_type,
                              int* reply_len)
  {
    if (nlmsg->pos > nlmsg->buf + sizeof(nlmsg->buf) || nlmsg->nesting)
      exit(1);
    struct nlmsghdr* hdr = (struct nlmsghdr*)nlmsg->buf;
    hdr->nlmsg_len = nlmsg->pos - nlmsg->buf;
    struct sockaddr_nl addr;
    memset(&addr, 0, sizeof(addr));
    addr.nl_family = AF_NETLINK;
    unsigned n = sendto(sock, nlmsg->buf, hdr->nlmsg_len, 0,
                        (struct sockaddr*)&addr, sizeof(addr));
    if (n != hdr->nlmsg_len)
      exit(1);
    n = recv(sock, nlmsg->buf, sizeof(nlmsg->buf), 0);
    if (hdr->nlmsg_type == NLMSG_DONE) {
      *reply_len = 0;
      return 0;
    }
    if (n < sizeof(struct nlmsghdr))
      exit(1);
    if (reply_len && hdr->nlmsg_type == reply_type) {
      *reply_len = n;
      return 0;
    }
    if (n < sizeof(struct nlmsghdr) + sizeof(struct nlmsgerr))
      exit(1);
    if (hdr->nlmsg_type != NLMSG_ERROR)
      exit(1);
    return -((struct nlmsgerr*)(hdr + 1))->error;
  }
  
  static int netlink_send(struct nlmsg* nlmsg, int sock)
  {
    return netlink_send_ext(nlmsg, sock, 0, NULL);
  }
  
  static int netlink_next_msg(struct nlmsg* nlmsg, unsigned int offset,
                              unsigned int total_len)
  {
    struct nlmsghdr* hdr = (struct nlmsghdr*)(nlmsg->buf + offset);
    if (offset == total_len || offset + hdr->nlmsg_len > total_len)
      return -1;
    return hdr->nlmsg_len;
  }
  
  static void netlink_add_device_impl(struct nlmsg* nlmsg, const char* type,
                                      const char* name)
  {
    struct ifinfomsg hdr;
    memset(&hdr, 0, sizeof(hdr));
    netlink_init(nlmsg, RTM_NEWLINK, NLM_F_EXCL | NLM_F_CREATE, &hdr,
                 sizeof(hdr));
    if (name)
      netlink_attr(nlmsg, IFLA_IFNAME, name, strlen(name));
    netlink_nest(nlmsg, IFLA_LINKINFO);
    netlink_attr(nlmsg, IFLA_INFO_KIND, type, strlen(type));
  }
  
  static void netlink_add_device(struct nlmsg* nlmsg, int sock, const char* type,
                                 const char* name)
  {
    netlink_add_device_impl(nlmsg, type, name);
    netlink_done(nlmsg);
    int err = netlink_send(nlmsg, sock);
    (void)err;
  }
  
  static void netlink_add_veth(struct nlmsg* nlmsg, int sock, const char* name,
                               const char* peer)
  {
    netlink_add_device_impl(nlmsg, "veth", name);
    netlink_nest(nlmsg, IFLA_INFO_DATA);
    netlink_nest(nlmsg, VETH_INFO_PEER);
    nlmsg->pos += sizeof(struct ifinfomsg);
    netlink_attr(nlmsg, IFLA_IFNAME, peer, strlen(peer));
    netlink_done(nlmsg);
    netlink_done(nlmsg);
    netlink_done(nlmsg);
    int err = netlink_send(nlmsg, sock);
    (void)err;
  }
  
  static void netlink_add_hsr(struct nlmsg* nlmsg, int sock, const char* name,
                              const char* slave1, const char* slave2)
  {
    netlink_add_device_impl(nlmsg, "hsr", name);
    netlink_nest(nlmsg, IFLA_INFO_DATA);
    int ifindex1 = if_nametoindex(slave1);
    netlink_attr(nlmsg, IFLA_HSR_SLAVE1, &ifindex1, sizeof(ifindex1));
    int ifindex2 = if_nametoindex(slave2);
    netlink_attr(nlmsg, IFLA_HSR_SLAVE2, &ifindex2, sizeof(ifindex2));
    netlink_done(nlmsg);
    netlink_done(nlmsg);
    int err = netlink_send(nlmsg, sock);
    (void)err;
  }
  
  static void netlink_add_virt_wifi(struct nlmsg* nlmsg, int sock,
                                    const char* name, const char* link)
  {
    netlink_add_device_impl(nlmsg, "virt_wifi", name);
    netlink_done(nlmsg);
    int ifindex = if_nametoindex(link);
    netlink_attr(nlmsg, IFLA_LINK, &ifindex, sizeof(ifindex));
    int err = netlink_send(nlmsg, sock);
    (void)err;
  }
  
  static void netlink_add_vlan(struct nlmsg* nlmsg, int sock, const char* name,
                               const char* link, uint16_t id, uint16_t proto)
  {
    netlink_add_device_impl(nlmsg, "vlan", name);
    netlink_nest(nlmsg, IFLA_INFO_DATA);
    netlink_attr(nlmsg, IFLA_VLAN_ID, &id, sizeof(id));
    netlink_attr(nlmsg, IFLA_VLAN_PROTOCOL, &proto, sizeof(proto));
    netlink_done(nlmsg);
    netlink_done(nlmsg);
    int ifindex = if_nametoindex(link);
    netlink_attr(nlmsg, IFLA_LINK, &ifindex, sizeof(ifindex));
    int err = netlink_send(nlmsg, sock);
    (void)err;
  }
  
  static void netlink_add_macvlan(struct nlmsg* nlmsg, int sock, const char* name,
                                  const char* link)
  {
    netlink_add_device_impl(nlmsg, "macvlan", name);
    netlink_nest(nlmsg, IFLA_INFO_DATA);
    uint32_t mode = MACVLAN_MODE_BRIDGE;
    netlink_attr(nlmsg, IFLA_MACVLAN_MODE, &mode, sizeof(mode));
    netlink_done(nlmsg);
    netlink_done(nlmsg);
    int ifindex = if_nametoindex(link);
    netlink_attr(nlmsg, IFLA_LINK, &ifindex, sizeof(ifindex));
    int err = netlink_send(nlmsg, sock);
    (void)err;
  }
  
  #define IFLA_IPVLAN_FLAGS 2
  #define IPVLAN_MODE_L3S 2
  #undef IPVLAN_F_VEPA
  #define IPVLAN_F_VEPA 2
  
  static void netlink_add_ipvlan(struct nlmsg* nlmsg, int sock, const char* name,
                                 const char* link, uint16_t mode, uint16_t flags)
  {
    netlink_add_device_impl(nlmsg, "ipvlan", name);
    netlink_nest(nlmsg, IFLA_INFO_DATA);
    netlink_attr(nlmsg, IFLA_IPVLAN_MODE, &mode, sizeof(mode));
    netlink_attr(nlmsg, IFLA_IPVLAN_FLAGS, &flags, sizeof(flags));
    netlink_done(nlmsg);
    netlink_done(nlmsg);
    int ifindex = if_nametoindex(link);
    netlink_attr(nlmsg, IFLA_LINK, &ifindex, sizeof(ifindex));
    int err = netlink_send(nlmsg, sock);
    (void)err;
  }
  
  static void netlink_device_change(struct nlmsg* nlmsg, int sock,
                                    const char* name, bool up, const char* master,
                                    const void* mac, int macsize,
                                    const char* new_name)
  {
    struct ifinfomsg hdr;
    memset(&hdr, 0, sizeof(hdr));
    if (up)
      hdr.ifi_flags = hdr.ifi_change = IFF_UP;
    hdr.ifi_index = if_nametoindex(name);
    netlink_init(nlmsg, RTM_NEWLINK, 0, &hdr, sizeof(hdr));
    if (new_name)
      netlink_attr(nlmsg, IFLA_IFNAME, new_name, strlen(new_name));
    if (master) {
      int ifindex = if_nametoindex(master);
      netlink_attr(nlmsg, IFLA_MASTER, &ifindex, sizeof(ifindex));
    }
    if (macsize)
      netlink_attr(nlmsg, IFLA_ADDRESS, mac, macsize);
    int err = netlink_send(nlmsg, sock);
    (void)err;
  }
  
  static int netlink_add_addr(struct nlmsg* nlmsg, int sock, const char* dev,
                              const void* addr, int addrsize)
  {
    struct ifaddrmsg hdr;
    memset(&hdr, 0, sizeof(hdr));
    hdr.ifa_family = addrsize == 4 ? AF_INET : AF_INET6;
    hdr.ifa_prefixlen = addrsize == 4 ? 24 : 120;
    hdr.ifa_scope = RT_SCOPE_UNIVERSE;
    hdr.ifa_index = if_nametoindex(dev);
    netlink_init(nlmsg, RTM_NEWADDR, NLM_F_CREATE | NLM_F_REPLACE, &hdr,
                 sizeof(hdr));
    netlink_attr(nlmsg, IFA_LOCAL, addr, addrsize);
    netlink_attr(nlmsg, IFA_ADDRESS, addr, addrsize);
    return netlink_send(nlmsg, sock);
  }
  
  static void netlink_add_addr4(struct nlmsg* nlmsg, int sock, const char* dev,
                                const char* addr)
  {
    struct in_addr in_addr;
    inet_pton(AF_INET, addr, &in_addr);
    int err = netlink_add_addr(nlmsg, sock, dev, &in_addr, sizeof(in_addr));
    (void)err;
  }
  
  static void netlink_add_addr6(struct nlmsg* nlmsg, int sock, const char* dev,
                                const char* addr)
  {
    struct in6_addr in6_addr;
    inet_pton(AF_INET6, addr, &in6_addr);
    int err = netlink_add_addr(nlmsg, sock, dev, &in6_addr, sizeof(in6_addr));
    (void)err;
  }
  
  const int kInitNetNsFd = 239;
  
  #define DEVLINK_FAMILY_NAME "devlink"
  
  #define DEVLINK_CMD_PORT_GET 5
  #define DEVLINK_CMD_RELOAD 37
  #define DEVLINK_ATTR_BUS_NAME 1
  #define DEVLINK_ATTR_DEV_NAME 2
  #define DEVLINK_ATTR_NETDEV_NAME 7
  #define DEVLINK_ATTR_NETNS_FD 138
  
  static int netlink_devlink_id_get(struct nlmsg* nlmsg, int sock)
  {
    struct genlmsghdr genlhdr;
    struct nlattr* attr;
    int err, n;
    uint16_t id = 0;
    memset(&genlhdr, 0, sizeof(genlhdr));
    genlhdr.cmd = CTRL_CMD_GETFAMILY;
    netlink_init(nlmsg, GENL_ID_CTRL, 0, &genlhdr, sizeof(genlhdr));
    netlink_attr(nlmsg, CTRL_ATTR_FAMILY_NAME, DEVLINK_FAMILY_NAME,
                 strlen(DEVLINK_FAMILY_NAME) + 1);
    err = netlink_send_ext(nlmsg, sock, GENL_ID_CTRL, &n);
    if (err) {
      return -1;
    }
    attr = (struct nlattr*)(nlmsg->buf + NLMSG_HDRLEN +
                            NLMSG_ALIGN(sizeof(genlhdr)));
    for (; (char*)attr < nlmsg->buf + n;
         attr = (struct nlattr*)((char*)attr + NLMSG_ALIGN(attr->nla_len))) {
      if (attr->nla_type == CTRL_ATTR_FAMILY_ID) {
        id = *(uint16_t*)(attr + 1);
        break;
      }
    }
    if (!id) {
      return -1;
    }
    recv(sock, nlmsg->buf, sizeof(nlmsg->buf), 0); /* recv ack */
    return id;
  }
  
  static void netlink_devlink_netns_move(const char* bus_name,
                                         const char* dev_name, int netns_fd)
  {
    struct genlmsghdr genlhdr;
    int sock;
    int id, err;
    sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_GENERIC);
    if (sock == -1)
      exit(1);
    id = netlink_devlink_id_get(&nlmsg, sock);
    if (id == -1)
      goto error;
    memset(&genlhdr, 0, sizeof(genlhdr));
    genlhdr.cmd = DEVLINK_CMD_RELOAD;
    netlink_init(&nlmsg, id, 0, &genlhdr, sizeof(genlhdr));
    netlink_attr(&nlmsg, DEVLINK_ATTR_BUS_NAME, bus_name, strlen(bus_name) + 1);
    netlink_attr(&nlmsg, DEVLINK_ATTR_DEV_NAME, dev_name, strlen(dev_name) + 1);
    netlink_attr(&nlmsg, DEVLINK_ATTR_NETNS_FD, &netns_fd, sizeof(netns_fd));
    err = netlink_send(&nlmsg, sock);
    if (err) {
    }
  error:
    close(sock);
  }
  
  static struct nlmsg nlmsg2;
  
  static void initialize_devlink_ports(const char* bus_name, const char* dev_name,
                                       const char* netdev_prefix)
  {
    struct genlmsghdr genlhdr;
    int len, total_len, id, err, offset;
    uint16_t netdev_index;
    int sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_GENERIC);
    if (sock == -1)
      exit(1);
    int rtsock = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
    if (rtsock == -1)
      exit(1);
    id = netlink_devlink_id_get(&nlmsg, sock);
    if (id == -1)
      goto error;
    memset(&genlhdr, 0, sizeof(genlhdr));
    genlhdr.cmd = DEVLINK_CMD_PORT_GET;
    netlink_init(&nlmsg, id, NLM_F_DUMP, &genlhdr, sizeof(genlhdr));
    netlink_attr(&nlmsg, DEVLINK_ATTR_BUS_NAME, bus_name, strlen(bus_name) + 1);
    netlink_attr(&nlmsg, DEVLINK_ATTR_DEV_NAME, dev_name, strlen(dev_name) + 1);
    err = netlink_send_ext(&nlmsg, sock, id, &total_len);
    if (err) {
      goto error;
    }
    offset = 0;
    netdev_index = 0;
    while ((len = netlink_next_msg(&nlmsg, offset, total_len)) != -1) {
      struct nlattr* attr = (struct nlattr*)(nlmsg.buf + offset + NLMSG_HDRLEN +
                                             NLMSG_ALIGN(sizeof(genlhdr)));
      for (; (char*)attr < nlmsg.buf + offset + len;
           attr = (struct nlattr*)((char*)attr + NLMSG_ALIGN(attr->nla_len))) {
        if (attr->nla_type == DEVLINK_ATTR_NETDEV_NAME) {
          char* port_name;
          char netdev_name[IFNAMSIZ];
          port_name = (char*)(attr + 1);
          snprintf(netdev_name, sizeof(netdev_name), "%s%d", netdev_prefix,
                   netdev_index);
          netlink_device_change(&nlmsg2, rtsock, port_name, true, 0, 0, 0,
                                netdev_name);
          break;
        }
      }
      offset += len;
      netdev_index++;
    }
  error:
    close(rtsock);
    close(sock);
  }
  
  static void initialize_devlink_pci(void)
  {
    int netns = open("/proc/self/ns/net", O_RDONLY);
    if (netns == -1)
      exit(1);
    int ret = setns(kInitNetNsFd, 0);
    if (ret == -1)
      exit(1);
    netlink_devlink_netns_move("pci", "0000:00:10.0", netns);
    ret = setns(netns, 0);
    if (ret == -1)
      exit(1);
    close(netns);
    initialize_devlink_ports("pci", "0000:00:10.0", "netpci");
  }
  
  #define DEV_IPV4 "172.20.20.%d"
  #define DEV_IPV6 "fe80::%02x"
  #define DEV_MAC 0x00aaaaaaaaaa
  
  static void netdevsim_add(unsigned int addr, unsigned int port_count)
  {
    char buf[16];
    sprintf(buf, "%u %u", addr, port_count);
    if (write_file("/sys/bus/netdevsim/new_device", buf)) {
      snprintf(buf, sizeof(buf), "netdevsim%d", addr);
      initialize_devlink_ports("netdevsim", buf, "netdevsim");
    }
  }
  static void initialize_netdevices(void)
  {
    char netdevsim[16];
    sprintf(netdevsim, "netdevsim%d", (int)procid);
    struct {
      const char* type;
      const char* dev;
    } devtypes[] = {
        {"ip6gretap", "ip6gretap0"}, {"bridge", "bridge0"},
        {"vcan", "vcan0"},           {"bond", "bond0"},
        {"team", "team0"},           {"dummy", "dummy0"},
        {"nlmon", "nlmon0"},         {"caif", "caif0"},
        {"batadv", "batadv0"},       {"vxcan", "vxcan1"},
        {"netdevsim", netdevsim},    {"veth", 0},
        {"xfrm", "xfrm0"},
    };
    const char* devmasters[] = {"bridge", "bond", "team"};
    struct {
      const char* name;
      int macsize;
      bool noipv6;
    } devices[] = {
        {"lo", ETH_ALEN},
        {"sit0", 0},
        {"bridge0", ETH_ALEN},
        {"vcan0", 0, true},
        {"tunl0", 0},
        {"gre0", 0},
        {"gretap0", ETH_ALEN},
        {"ip_vti0", 0},
        {"ip6_vti0", 0},
        {"ip6tnl0", 0},
        {"ip6gre0", 0},
        {"ip6gretap0", ETH_ALEN},
        {"erspan0", ETH_ALEN},
        {"bond0", ETH_ALEN},
        {"veth0", ETH_ALEN},
        {"veth1", ETH_ALEN},
        {"team0", ETH_ALEN},
        {"veth0_to_bridge", ETH_ALEN},
        {"veth1_to_bridge", ETH_ALEN},
        {"veth0_to_bond", ETH_ALEN},
        {"veth1_to_bond", ETH_ALEN},
        {"veth0_to_team", ETH_ALEN},
        {"veth1_to_team", ETH_ALEN},
        {"veth0_to_hsr", ETH_ALEN},
        {"veth1_to_hsr", ETH_ALEN},
        {"hsr0", 0},
        {"dummy0", ETH_ALEN},
        {"nlmon0", 0},
        {"vxcan0", 0, true},
        {"vxcan1", 0, true},
        {"caif0", ETH_ALEN},
        {"batadv0", ETH_ALEN},
        {netdevsim, ETH_ALEN},
        {"xfrm0", ETH_ALEN},
        {"veth0_virt_wifi", ETH_ALEN},
        {"veth1_virt_wifi", ETH_ALEN},
        {"virt_wifi0", ETH_ALEN},
        {"veth0_vlan", ETH_ALEN},
        {"veth1_vlan", ETH_ALEN},
        {"vlan0", ETH_ALEN},
        {"vlan1", ETH_ALEN},
        {"macvlan0", ETH_ALEN},
        {"macvlan1", ETH_ALEN},
        {"ipvlan0", ETH_ALEN},
        {"ipvlan1", ETH_ALEN},
    };
    int sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
    if (sock == -1)
      exit(1);
    unsigned i;
    for (i = 0; i < sizeof(devtypes) / sizeof(devtypes[0]); i++)
      netlink_add_device(&nlmsg, sock, devtypes[i].type, devtypes[i].dev);
    for (i = 0; i < sizeof(devmasters) / (sizeof(devmasters[0])); i++) {
      char master[32], slave0[32], veth0[32], slave1[32], veth1[32];
      sprintf(slave0, "%s_slave_0", devmasters[i]);
      sprintf(veth0, "veth0_to_%s", devmasters[i]);
      netlink_add_veth(&nlmsg, sock, slave0, veth0);
      sprintf(slave1, "%s_slave_1", devmasters[i]);
      sprintf(veth1, "veth1_to_%s", devmasters[i]);
      netlink_add_veth(&nlmsg, sock, slave1, veth1);
      sprintf(master, "%s0", devmasters[i]);
      netlink_device_change(&nlmsg, sock, slave0, false, master, 0, 0, NULL);
      netlink_device_change(&nlmsg, sock, slave1, false, master, 0, 0, NULL);
    }
    netlink_device_change(&nlmsg, sock, "bridge_slave_0", true, 0, 0, 0, NULL);
    netlink_device_change(&nlmsg, sock, "bridge_slave_1", true, 0, 0, 0, NULL);
    netlink_add_veth(&nlmsg, sock, "hsr_slave_0", "veth0_to_hsr");
    netlink_add_veth(&nlmsg, sock, "hsr_slave_1", "veth1_to_hsr");
    netlink_add_hsr(&nlmsg, sock, "hsr0", "hsr_slave_0", "hsr_slave_1");
    netlink_device_change(&nlmsg, sock, "hsr_slave_0", true, 0, 0, 0, NULL);
    netlink_device_change(&nlmsg, sock, "hsr_slave_1", true, 0, 0, 0, NULL);
    netlink_add_veth(&nlmsg, sock, "veth0_virt_wifi", "veth1_virt_wifi");
    netlink_add_virt_wifi(&nlmsg, sock, "virt_wifi0", "veth1_virt_wifi");
    netlink_add_veth(&nlmsg, sock, "veth0_vlan", "veth1_vlan");
    netlink_add_vlan(&nlmsg, sock, "vlan0", "veth0_vlan", 0, htons(ETH_P_8021Q));
    netlink_add_vlan(&nlmsg, sock, "vlan1", "veth0_vlan", 1, htons(ETH_P_8021AD));
    netlink_add_macvlan(&nlmsg, sock, "macvlan0", "veth1_vlan");
    netlink_add_macvlan(&nlmsg, sock, "macvlan1", "veth1_vlan");
    netlink_add_ipvlan(&nlmsg, sock, "ipvlan0", "veth0_vlan", IPVLAN_MODE_L2, 0);
    netlink_add_ipvlan(&nlmsg, sock, "ipvlan1", "veth0_vlan", IPVLAN_MODE_L3S,
                       IPVLAN_F_VEPA);
    netdevsim_add((int)procid, 4);
    for (i = 0; i < sizeof(devices) / (sizeof(devices[0])); i++) {
      char addr[32];
      sprintf(addr, DEV_IPV4, i + 10);
      netlink_add_addr4(&nlmsg, sock, devices[i].name, addr);
      if (!devices[i].noipv6) {
        sprintf(addr, DEV_IPV6, i + 10);
        netlink_add_addr6(&nlmsg, sock, devices[i].name, addr);
      }
      uint64_t macaddr = DEV_MAC + ((i + 10ull) << 40);
      netlink_device_change(&nlmsg, sock, devices[i].name, true, 0, &macaddr,
                            devices[i].macsize, NULL);
    }
    close(sock);
  }
  static void initialize_netdevices_init(void)
  {
    int sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
    if (sock == -1)
      exit(1);
    struct {
      const char* type;
      int macsize;
      bool noipv6;
      bool noup;
    } devtypes[] = {
        {"nr", 7, true},
        {"rose", 5, true, true},
    };
    unsigned i;
    for (i = 0; i < sizeof(devtypes) / sizeof(devtypes[0]); i++) {
      char dev[32], addr[32];
      sprintf(dev, "%s%d", devtypes[i].type, (int)procid);
      sprintf(addr, "172.30.%d.%d", i, (int)procid + 1);
      netlink_add_addr4(&nlmsg, sock, dev, addr);
      if (!devtypes[i].noipv6) {
        sprintf(addr, "fe88::%02x:%02x", i, (int)procid + 1);
        netlink_add_addr6(&nlmsg, sock, dev, addr);
      }
      int macsize = devtypes[i].macsize;
      uint64_t macaddr = 0xbbbbbb +
                         ((unsigned long long)i << (8 * (macsize - 2))) +
                         (procid << (8 * (macsize - 1)));
      netlink_device_change(&nlmsg, sock, dev, !devtypes[i].noup, 0, &macaddr,
                            macsize, NULL);
    }
    close(sock);
  }
  
  static void setup_common()
  {
    if (mount(0, "/sys/fs/fuse/connections", "fusectl", 0, 0)) {
    }
  }
  
  static void loop();
  
  static void sandbox_common()
  {
    prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0);
    setpgrp();
    setsid();
    int netns = open("/proc/self/ns/net", O_RDONLY);
    if (netns == -1)
      exit(1);
    if (dup2(netns, kInitNetNsFd) < 0)
      exit(1);
    close(netns);
    struct rlimit rlim;
    rlim.rlim_cur = rlim.rlim_max = (200 << 20);
    setrlimit(RLIMIT_AS, &rlim);
    rlim.rlim_cur = rlim.rlim_max = 32 << 20;
    setrlimit(RLIMIT_MEMLOCK, &rlim);
    rlim.rlim_cur = rlim.rlim_max = 136 << 20;
    setrlimit(RLIMIT_FSIZE, &rlim);
    rlim.rlim_cur = rlim.rlim_max = 1 << 20;
    setrlimit(RLIMIT_STACK, &rlim);
    rlim.rlim_cur = rlim.rlim_max = 0;
    setrlimit(RLIMIT_CORE, &rlim);
    rlim.rlim_cur = rlim.rlim_max = 256;
    setrlimit(RLIMIT_NOFILE, &rlim);
    if (unshare(CLONE_NEWNS)) {
    }
    if (unshare(CLONE_NEWIPC)) {
    }
    if (unshare(0x02000000)) {
    }
    if (unshare(CLONE_NEWUTS)) {
    }
    if (unshare(CLONE_SYSVSEM)) {
    }
    typedef struct {
      const char* name;
      const char* value;
    } sysctl_t;
    static const sysctl_t sysctls[] = {
        {"/proc/sys/kernel/shmmax", "16777216"},
        {"/proc/sys/kernel/shmall", "536870912"},
        {"/proc/sys/kernel/shmmni", "1024"},
        {"/proc/sys/kernel/msgmax", "8192"},
        {"/proc/sys/kernel/msgmni", "1024"},
        {"/proc/sys/kernel/msgmnb", "1024"},
        {"/proc/sys/kernel/sem", "1024 1048576 500 1024"},
    };
    unsigned i;
    for (i = 0; i < sizeof(sysctls) / sizeof(sysctls[0]); i++)
      write_file(sysctls[i].name, sysctls[i].value);
  }
  
  int wait_for_loop(int pid)
  {
    if (pid < 0)
      exit(1);
    int status = 0;
    while (waitpid(-1, &status, __WALL) != pid) {
    }
    return WEXITSTATUS(status);
  }
  
  static void drop_caps(void)
  {
    struct __user_cap_header_struct cap_hdr = {};
    struct __user_cap_data_struct cap_data[2] = {};
    cap_hdr.version = _LINUX_CAPABILITY_VERSION_3;
    cap_hdr.pid = getpid();
    if (syscall(SYS_capget, &cap_hdr, &cap_data))
      exit(1);
    const int drop = (1 << CAP_SYS_PTRACE) | (1 << CAP_SYS_NICE);
    cap_data[0].effective &= ~drop;
    cap_data[0].permitted &= ~drop;
    cap_data[0].inheritable &= ~drop;
    if (syscall(SYS_capset, &cap_hdr, &cap_data))
      exit(1);
  }
  
  static int do_sandbox_none(void)
  {
    if (unshare(CLONE_NEWPID)) {
    }
    int pid = fork();
    if (pid != 0)
      return wait_for_loop(pid);
    setup_common();
    sandbox_common();
    drop_caps();
    initialize_netdevices_init();
    if (unshare(CLONE_NEWNET)) {
    }
    initialize_devlink_pci();
    initialize_netdevices();
    loop();
    exit(1);
  }
  
  uint64_t r[3] = {0xffffffffffffffff, 0xffffffffffffffff, 0xffffffffffffffff};
  
  void loop(void)
  {
    intptr_t res = 0;
    res = syscall(__NR_socket, 2ul, 2ul, 0ul);
    if (res != -1)
      r[0] = res;
    memcpy((void*)0x20000600, "bridge_slave_1\000\000", 16);
    *(uint32_t*)0x20000610 = 0;
    res = syscall(__NR_ioctl, r[0], 0x8933ul, 0x20000600ul);
    if (res != -1)
      r[1] = *(uint32_t*)0x20000610;
    *(uint64_t*)0x20000240 = 0;
    *(uint32_t*)0x20000248 = 0;
    *(uint64_t*)0x20000250 = 0x200000c0;
    *(uint64_t*)0x200000c0 = 0x20000280;
    memcpy((void*)0x20000280,
           "\xcc\x00\x00\x00\x24\x00\x07\x8f\x96\xcd\x03\x37\xcc\xc5\x5e\xb2\x98"
           "\x92\xa1\x37",
           20);
    *(uint32_t*)0x20000294 = r[1];
    memcpy(
        (void*)0x20000298,
        "\x00\x00\x00\x00\xff\xff\xff\xff\x00\x00\x00\x00\x09\x00\x01\x00\x6e\x65"
        "\x74\x65\x6d\x00\x00\x00\x4c\x00\x02\x00\x00\x00\x00\x00\x00\x23\x58\x48"
        "\x48\x00\x00\x00\x00\x00\x00\x00\x00\xb2\x00\x00\x00\x00\x00\x00\x0c\x00"
        "\x04\x00\x00\x00\xed\x6f\x65\x00\x00\x00\x0c\x00\x05\x00\x05\x22\x02\x00"
        "\x00\x00\x00\x00\x0c\x00\x0b\x00\x00\x00\x00\x80\x00\x00\x00\x00\x0c\x00"
        "\x03\x00\x00\x00\x00\x01\x00\x68\x74\xe9\xac\x68\x31\xbd\x62\x5d\x65\x05"
        "\x00\x08\x00\x00\x00\x00\x00\x05\x00\x36\xba\x51\xa9\xec\xc5\xdd\x7f\xca"
        "\x93\x66\xa9\xb5\x0c\xe6\x00\x00\x00\x00\x00\x00\x02\x00\x03\x00\x00\x00"
        "\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x04\x00\x00\x00\x00\x00\xf3\xff"
        "\x04\x02\x00\x00\x00\x00\x00\x00\x05\x00\x00\x00\x00\x00\x00\x00\x02\x00"
        "\x03\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
        "\x00\x00\xd5\xc0\x0e\x37\x12\x26\x00\x00\x05\x00\x00\x00\x00\x00\x00\x00"
        "\x02\x00\x03\x00\x00\x00\x00\x00\x00\x00\x00\x04\x01\x00\x00\x00\xcf\xf6"
        "\xae\x85\xf6\x23\xc1\xc7\x41\x0e\x1c\x94\xe0\xa1\x89\x12\xc2\x39\x89\x3b"
        "\xa7\xee\x18\xe6\xb8\x7c\xc7\xeb\x42\x53\x57\xf8\x3f\xee\x96\xc9\xc3\x0b"
        "\x2a\x9b\xde\xb9\x14\x79\xea\xfd\x9d\x18\xe6\x30\xab\xfb\x4a\x80\x9c\x74"
        "\x26\x4f\x1c\xb2\x8e\xf7\xac\x3d\x3c\x34\xaf\x4a\x07\x9b\xd7\x52\x5e\x67"
        "\x2a\x53\xa4\xd2\xd3\xe8\xa6\x05\x37\x06\x00\x00\x00\xcd\xea\xca\xa2\x61"
        "\xe5\x20\x6c\xdd\x3e\xa4\xa8\x90\x5b\xf3\xf5\x9c\x38\x9a\x9f\xba\x15\x18"
        "\xa2\x2b\xa4\x81\x89\xbf\x31\x36\x94\x41\x58\x78\x2e\x76\x64\x20\x65\xa0"
        "\xa8\x46\x21\xeb\x10\x5a\xb7\x92\xa1\x86\xdf\x6d\x5d\x5b\xb7\x98\x00\x00"
        "\x00\x00\x00\x00\x00",
        383);
    *(uint64_t*)0x200000c8 = 0xcc;
    *(uint64_t*)0x20000258 = 1;
    *(uint64_t*)0x20000260 = 0;
    *(uint64_t*)0x20000268 = 0;
    *(uint32_t*)0x20000270 = 0;
    syscall(__NR_sendmsg, -1, 0x20000240ul, 0ul);
    res = syscall(__NR_socket, 0x10ul, 0x80002ul, 0);
    if (res != -1)
      r[2] = res;
    *(uint64_t*)0x20000180 = 2;
    *(uint32_t*)0x20000188 = 0;
    *(uint64_t*)0x20000190 = 0x20000080;
    *(uint64_t*)0x20000198 = 0xe;
    *(uint64_t*)0x200001a0 = 0x20000100;
    *(uint64_t*)0x200001a8 = 0;
    *(uint32_t*)0x200001b0 = 0;
    syscall(__NR_sendmmsg, r[2], 0x20000180ul, 0x492492492492642ul, 0ul);
  }
  int main(void)
  {
    syscall(__NR_mmap, 0x20000000ul, 0x1000000ul, 3ul, 0x32ul, -1, 0);
    do_sandbox_none();
    return 0;
  }
  