text: // divide error in tabledist
  // https://syzkaller.appspot.com/bug?id=8a97e22f54c66146e565e3d1832be7b30c9a8d4f
  // status:open
  // 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/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 use_temporary_dir(void)
  {
    char tmpdir_template[] = "./syzkaller.XXXXXX";
    char* tmpdir = mkdtemp(tmpdir_template);
    if (!tmpdir)
      exit(1);
    if (chmod(tmpdir, 0777))
      exit(1);
    if (chdir(tmpdir))
      exit(1);
  }
  
  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 netdevsim_add(unsigned int addr, unsigned int port_count)
  {
    char buf[16];
    sprintf(buf, "%u %u", addr, port_count);
    write_file("/sys/bus/netdevsim/new_device", buf);
  }
  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);
    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(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);
  }
  
  #define MAX_FDS 30
  
  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 close_fds()
  {
    int fd;
    for (fd = 3; fd < MAX_FDS; fd++)
      close(fd);
  }
  
  uint64_t r[3] = {0xffffffffffffffff, 0xffffffffffffffff, 0xffffffffffffffff};
  
  void loop(void)
  {
    intptr_t res = 0;
    res = syscall(__NR_socket, 0x10, 3, 0);
    if (res != -1)
      r[0] = res;
    res = syscall(__NR_socket, 2, 2, 0);
    if (res != -1)
      r[1] = res;
    memcpy((void*)0x20000600, "bridge_slave_1\000\000", 16);
    *(uint32_t*)0x20000610 = 0;
    res = syscall(__NR_ioctl, r[1], 0x8933, 0x20000600);
    if (res != -1)
      r[2] = *(uint32_t*)0x20000610;
    *(uint64_t*)0x20000240 = 0;
    *(uint32_t*)0x20000248 = 0;
    *(uint64_t*)0x20000250 = 0x200000c0;
    *(uint64_t*)0x200000c0 = 0x20000000;
    memcpy((void*)0x20000000, "\x4c\x00\x00\x00\x24\x00\x07\x05\x00\x00\x00\x00"
                              "\x00\x00\x00\x00\x00\x00\x00\x00",
           20);
    *(uint32_t*)0x20000014 = r[2];
    memcpy((void*)0x20000018,
           "\x00\x00\x00\x00\xff\xff\xff\xff\x00\x00\x00\x00\x0a\x00\x01\x00\x6e"
           "\x65\x74\x65\x6d\x00\x00\x00\x1c\x00\x02\x00\x00\x00\x00\x00\x00\x00"
           "\x5b\x2f\x00\xba\xb5\x60\x90\x70\x45\xc4\x45\x87\x00\x00\x00\x00\x00"
           "\x02\x00\x00\x00\xf0\x26\x00\x00\x00\x00",
           61);
    *(uint64_t*)0x200000c8 = 0x4c;
    *(uint64_t*)0x20000258 = 1;
    *(uint64_t*)0x20000260 = 0;
    *(uint64_t*)0x20000268 = 0;
    *(uint32_t*)0x20000270 = 0;
    syscall(__NR_sendmsg, r[0], 0x20000240, 0);
    close_fds();
  }
  int main(void)
  {
    syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0);
    use_temporary_dir();
    do_sandbox_none();
    return 0;
  }
  