text: // WARNING in tcp_send_loss_probe
  // https://syzkaller.appspot.com/bug?id=db93d2646236293ef2335803eff180435afa065e
  // status:open
  // autogenerated by syzkaller (https://github.com/google/syzkaller)
  
  #define _GNU_SOURCE
  
  #include <arpa/inet.h>
  #include <dirent.h>
  #include <endian.h>
  #include <errno.h>
  #include <fcntl.h>
  #include <net/if.h>
  #include <net/if_arp.h>
  #include <netinet/in.h>
  #include <pthread.h>
  #include <sched.h>
  #include <signal.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 <time.h>
  #include <unistd.h>
  
  #include <linux/capability.h>
  #include <linux/futex.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 void sleep_ms(uint64_t ms)
  {
    usleep(ms * 1000);
  }
  
  static uint64_t current_time_ms(void)
  {
    struct timespec ts;
    if (clock_gettime(CLOCK_MONOTONIC, &ts))
      exit(1);
    return (uint64_t)ts.tv_sec * 1000 + (uint64_t)ts.tv_nsec / 1000000;
  }
  
  static void thread_start(void* (*fn)(void*), void* arg)
  {
    pthread_t th;
    pthread_attr_t attr;
    pthread_attr_init(&attr);
    pthread_attr_setstacksize(&attr, 128 << 10);
    int i;
    for (i = 0; i < 100; i++) {
      if (pthread_create(&th, &attr, fn, arg) == 0) {
        pthread_attr_destroy(&attr);
        return;
      }
      if (errno == EAGAIN) {
        usleep(50);
        continue;
      }
      break;
    }
    exit(1);
  }
  
  typedef struct {
    int state;
  } event_t;
  
  static void event_init(event_t* ev)
  {
    ev->state = 0;
  }
  
  static void event_reset(event_t* ev)
  {
    ev->state = 0;
  }
  
  static void event_set(event_t* ev)
  {
    if (ev->state)
      exit(1);
    __atomic_store_n(&ev->state, 1, __ATOMIC_RELEASE);
    syscall(SYS_futex, &ev->state, FUTEX_WAKE | FUTEX_PRIVATE_FLAG);
  }
  
  static void event_wait(event_t* ev)
  {
    while (!__atomic_load_n(&ev->state, __ATOMIC_ACQUIRE))
      syscall(SYS_futex, &ev->state, FUTEX_WAIT | FUTEX_PRIVATE_FLAG, 0, 0);
  }
  
  static int event_isset(event_t* ev)
  {
    return __atomic_load_n(&ev->state, __ATOMIC_ACQUIRE);
  }
  
  static int event_timedwait(event_t* ev, uint64_t timeout)
  {
    uint64_t start = current_time_ms();
    uint64_t now = start;
    for (;;) {
      uint64_t remain = timeout - (now - start);
      struct timespec ts;
      ts.tv_sec = remain / 1000;
      ts.tv_nsec = (remain % 1000) * 1000 * 1000;
      syscall(SYS_futex, &ev->state, FUTEX_WAIT | FUTEX_PRIVATE_FLAG, 0, &ts);
      if (__atomic_load_n(&ev->state, __ATOMIC_RELAXED))
        return 1;
      now = current_time_ms();
      if (now - start > timeout)
        return 0;
    }
  }
  
  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;
  }
  
  static struct {
    char* pos;
    int nesting;
    struct nlattr* nested[8];
    char buf[1024];
  } nlmsg;
  
  static void netlink_init(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(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(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(void)
  {
    struct nlattr* attr = nlmsg.nested[--nlmsg.nesting];
    attr->nla_len = nlmsg.pos - (char*)attr;
  }
  
  static int netlink_send(int sock)
  {
    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 (n < sizeof(struct nlmsghdr) + sizeof(struct nlmsgerr))
      exit(1);
    if (hdr->nlmsg_type != NLMSG_ERROR)
      exit(1);
    return -((struct nlmsgerr*)(hdr + 1))->error;
  }
  
  static void netlink_add_device_impl(const char* type, const char* name)
  {
    struct ifinfomsg hdr;
    memset(&hdr, 0, sizeof(hdr));
    netlink_init(RTM_NEWLINK, NLM_F_EXCL | NLM_F_CREATE, &hdr, sizeof(hdr));
    if (name)
      netlink_attr(IFLA_IFNAME, name, strlen(name));
    netlink_nest(IFLA_LINKINFO);
    netlink_attr(IFLA_INFO_KIND, type, strlen(type));
  }
  
  static void netlink_add_device(int sock, const char* type, const char* name)
  {
    netlink_add_device_impl(type, name);
    netlink_done();
    int err = netlink_send(sock);
    (void)err;
  }
  
  static void netlink_add_veth(int sock, const char* name, const char* peer)
  {
    netlink_add_device_impl("veth", name);
    netlink_nest(IFLA_INFO_DATA);
    netlink_nest(VETH_INFO_PEER);
    nlmsg.pos += sizeof(struct ifinfomsg);
    netlink_attr(IFLA_IFNAME, peer, strlen(peer));
    netlink_done();
    netlink_done();
    netlink_done();
    int err = netlink_send(sock);
    (void)err;
  }
  
  static void netlink_add_hsr(int sock, const char* name, const char* slave1,
                              const char* slave2)
  {
    netlink_add_device_impl("hsr", name);
    netlink_nest(IFLA_INFO_DATA);
    int ifindex1 = if_nametoindex(slave1);
    netlink_attr(IFLA_HSR_SLAVE1, &ifindex1, sizeof(ifindex1));
    int ifindex2 = if_nametoindex(slave2);
    netlink_attr(IFLA_HSR_SLAVE2, &ifindex2, sizeof(ifindex2));
    netlink_done();
    netlink_done();
    int err = netlink_send(sock);
    (void)err;
  }
  
  static void netlink_device_change(int sock, const char* name, bool up,
                                    const char* master, const void* mac,
                                    int macsize)
  {
    struct ifinfomsg hdr;
    memset(&hdr, 0, sizeof(hdr));
    if (up)
      hdr.ifi_flags = hdr.ifi_change = IFF_UP;
    netlink_init(RTM_NEWLINK, 0, &hdr, sizeof(hdr));
    netlink_attr(IFLA_IFNAME, name, strlen(name));
    if (master) {
      int ifindex = if_nametoindex(master);
      netlink_attr(IFLA_MASTER, &ifindex, sizeof(ifindex));
    }
    if (macsize)
      netlink_attr(IFLA_ADDRESS, mac, macsize);
    int err = netlink_send(sock);
    (void)err;
  }
  
  static int netlink_add_addr(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(RTM_NEWADDR, NLM_F_CREATE | NLM_F_REPLACE, &hdr, sizeof(hdr));
    netlink_attr(IFA_LOCAL, addr, addrsize);
    netlink_attr(IFA_ADDRESS, addr, addrsize);
    return netlink_send(sock);
  }
  
  static void netlink_add_addr4(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(sock, dev, &in_addr, sizeof(in_addr));
    (void)err;
  }
  
  static void netlink_add_addr6(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(sock, dev, &in6_addr, sizeof(in6_addr));
    (void)err;
  }
  
  #define DEV_IPV4 "172.20.20.%d"
  #define DEV_IPV6 "fe80::%02x"
  #define DEV_MAC 0x00aaaaaaaaaa
  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},
    };
    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},
        {"vxcan1", 0, true},
        {"caif0", ETH_ALEN},
        {"batadv0", ETH_ALEN},
        {netdevsim, 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(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(sock, slave0, veth0);
      sprintf(slave1, "%s_slave_1", devmasters[i]);
      sprintf(veth1, "veth1_to_%s", devmasters[i]);
      netlink_add_veth(sock, slave1, veth1);
      sprintf(master, "%s0", devmasters[i]);
      netlink_device_change(sock, slave0, false, master, 0, 0);
      netlink_device_change(sock, slave1, false, master, 0, 0);
    }
    netlink_device_change(sock, "bridge_slave_0", true, 0, 0, 0);
    netlink_device_change(sock, "bridge_slave_1", true, 0, 0, 0);
    netlink_add_veth(sock, "hsr_slave_0", "veth0_to_hsr");
    netlink_add_veth(sock, "hsr_slave_1", "veth1_to_hsr");
    netlink_add_hsr(sock, "hsr0", "hsr_slave_0", "hsr_slave_1");
    netlink_device_change(sock, "hsr_slave_0", true, 0, 0, 0);
    netlink_device_change(sock, "hsr_slave_1", true, 0, 0, 0);
    for (i = 0; i < sizeof(devices) / (sizeof(devices[0])); i++) {
      char addr[32];
      sprintf(addr, DEV_IPV4, i + 10);
      netlink_add_addr4(sock, devices[i].name, addr);
      if (!devices[i].noipv6) {
        sprintf(addr, DEV_IPV6, i + 10);
        netlink_add_addr6(sock, devices[i].name, addr);
      }
      uint64_t macaddr = DEV_MAC + ((i + 10ull) << 40);
      netlink_device_change(sock, devices[i].name, true, 0, &macaddr,
                            devices[i].macsize);
    }
    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(sock, dev, addr);
      if (!devtypes[i].noipv6) {
        sprintf(addr, "fe88::%02x:%02x", i, (int)procid + 1);
        netlink_add_addr6(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(sock, dev, !devtypes[i].noup, 0, &macaddr, macsize);
    }
    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();
    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_netdevices();
    loop();
    exit(1);
  }
  
  static void kill_and_wait(int pid, int* status)
  {
    kill(-pid, SIGKILL);
    kill(pid, SIGKILL);
    int i;
    for (i = 0; i < 100; i++) {
      if (waitpid(-1, status, WNOHANG | __WALL) == pid)
        return;
      usleep(1000);
    }
    DIR* dir = opendir("/sys/fs/fuse/connections");
    if (dir) {
      for (;;) {
        struct dirent* ent = readdir(dir);
        if (!ent)
          break;
        if (strcmp(ent->d_name, ".") == 0 || strcmp(ent->d_name, "..") == 0)
          continue;
        char abort[300];
        snprintf(abort, sizeof(abort), "/sys/fs/fuse/connections/%s/abort",
                 ent->d_name);
        int fd = open(abort, O_WRONLY);
        if (fd == -1) {
          continue;
        }
        if (write(fd, abort, 1) < 0) {
        }
        close(fd);
      }
      closedir(dir);
    } else {
    }
    while (waitpid(-1, status, __WALL) != pid) {
    }
  }
  
  static void setup_test()
  {
    prctl(PR_SET_PDEATHSIG, SIGKILL, 0, 0, 0);
    setpgrp();
    write_file("/proc/self/oom_score_adj", "1000");
  }
  
  static void close_fds()
  {
    int fd;
    for (fd = 3; fd < 30; fd++)
      close(fd);
  }
  
  struct thread_t {
    int created, call;
    event_t ready, done;
  };
  
  static struct thread_t threads[16];
  static void execute_call(int call);
  static int running;
  
  static void* thr(void* arg)
  {
    struct thread_t* th = (struct thread_t*)arg;
    for (;;) {
      event_wait(&th->ready);
      event_reset(&th->ready);
      execute_call(th->call);
      __atomic_fetch_sub(&running, 1, __ATOMIC_RELAXED);
      event_set(&th->done);
    }
    return 0;
  }
  
  static void execute_one(void)
  {
    int i, call, thread;
    int collide = 0;
  again:
    for (call = 0; call < 8; call++) {
      for (thread = 0; thread < (int)(sizeof(threads) / sizeof(threads[0]));
           thread++) {
        struct thread_t* th = &threads[thread];
        if (!th->created) {
          th->created = 1;
          event_init(&th->ready);
          event_init(&th->done);
          event_set(&th->done);
          thread_start(thr, th);
        }
        if (!event_isset(&th->done))
          continue;
        event_reset(&th->done);
        th->call = call;
        __atomic_fetch_add(&running, 1, __ATOMIC_RELAXED);
        event_set(&th->ready);
        if (collide && (call % 2) == 0)
          break;
        event_timedwait(&th->done, 45);
        break;
      }
    }
    for (i = 0; i < 100 && __atomic_load_n(&running, __ATOMIC_RELAXED); i++)
      sleep_ms(1);
    close_fds();
    if (!collide) {
      collide = 1;
      goto again;
    }
  }
  
  static void execute_one(void);
  
  #define WAIT_FLAGS __WALL
  
  static void loop(void)
  {
    int iter;
    for (iter = 0;; iter++) {
      int pid = fork();
      if (pid < 0)
        exit(1);
      if (pid == 0) {
        setup_test();
        execute_one();
        exit(0);
      }
      int status = 0;
      uint64_t start = current_time_ms();
      for (;;) {
        if (waitpid(-1, &status, WNOHANG | WAIT_FLAGS) == pid)
          break;
        sleep_ms(1);
        if (current_time_ms() - start < 5 * 1000)
          continue;
        kill_and_wait(pid, &status);
        break;
      }
    }
  }
  
  uint64_t r[1] = {0xffffffffffffffff};
  
  void execute_call(int call)
  {
    intptr_t res;
    switch (call) {
    case 0:
      res = syscall(__NR_socket, 2, 0x4000000000000001, 0);
      if (res != -1)
        r[0] = res;
      break;
    case 1:
      *(uint16_t*)0x20000080 = 2;
      *(uint16_t*)0x20000082 = htobe16(0x4e23);
      *(uint32_t*)0x20000084 = htobe32(0xe0000002);
      syscall(__NR_bind, r[0], 0x20000080, 0x10);
      break;
    case 2:
      syscall(__NR_clone, 0x81000000, 0, 0x9999999999999999, 0, -1);
      break;
    case 3:
      *(uint16_t*)0x20000100 = 2;
      *(uint16_t*)0x20000102 = htobe16(0x4e23);
      *(uint8_t*)0x20000104 = 0xac;
      *(uint8_t*)0x20000105 = 0x14;
      *(uint8_t*)0x20000106 = 0x14;
      *(uint8_t*)0x20000107 = 0xa;
      syscall(__NR_sendto, r[0], 0, 0, 0x20000802, 0x20000100, 0x10);
      break;
    case 4:
      memcpy((void*)0x20000000, "ip6_vti0\000\000\000\000\000\000\000\000", 16);
      syscall(__NR_setsockopt, r[0], 1, 0x19, 0x20000000, 0x10);
      break;
    case 5:
      syscall(__NR_write, r[0], 0, 0);
      break;
    case 6:
      syscall(__NR_sendto, r[0], 0, 0, 0, 0, 0);
      break;
    case 7:
      syscall(__NR_shutdown, r[0], 1);
      break;
    }
  }
  int main(void)
  {
    syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0);
    do_sandbox_none();
    return 0;
  }
  