// https://syzkaller.appspot.com/bug?id=484ff88f6319975a6b7b9aad7341d0cb2d4411f5
// 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 <netinet/in.h>
#include <pthread.h>
#include <sched.h>
#include <stdarg.h>
#include <stdbool.h>
#include <stddef.h>
#include <stdint.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/epoll.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/in6.h>
#include <linux/loop.h>
#include <linux/neighbour.h>
#include <linux/net.h>
#include <linux/netlink.h>
#include <linux/nl80211.h>
#include <linux/rfkill.h>
#include <linux/rtnetlink.h>
#include <linux/veth.h>

static 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;
}

struct nlmsg {
  char* pos;
  int nesting;
  struct nlattr* nested[8];
  char buf[4096];
};

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;
  if (size > 0)
    memcpy(attr + 1, data, size);
  nlmsg->pos += NLMSG_ALIGN(attr->nla_len);
}

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 (reply_len)
    *reply_len = 0;
  if (hdr->nlmsg_type == NLMSG_DONE)
    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_query_family_id(struct nlmsg* nlmsg, int sock,
                                   const char* family_name)
{
  struct genlmsghdr genlhdr;
  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, family_name,
               strnlen(family_name, GENL_NAMSIZ - 1) + 1);
  int n = 0;
  int err = netlink_send_ext(nlmsg, sock, GENL_ID_CTRL, &n);
  if (err < 0) {
    return -1;
  }
  uint16_t id = 0;
  struct nlattr* 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);
  return id;
}

static struct nlmsg nlmsg;

#define WIFI_INITIAL_DEVICE_COUNT 2
#define WIFI_MAC_BASE                                                          \
  {                                                                            \
    0x08, 0x02, 0x11, 0x00, 0x00, 0x00                                         \
  }
#define WIFI_IBSS_BSSID                                                        \
  {                                                                            \
    0x50, 0x50, 0x50, 0x50, 0x50, 0x50                                         \
  }
#define WIFI_IBSS_SSID                                                         \
  {                                                                            \
    0x10, 0x10, 0x10, 0x10, 0x10, 0x10                                         \
  }
#define WIFI_DEFAULT_FREQUENCY 2412
#define WIFI_DEFAULT_SIGNAL 0
#define WIFI_DEFAULT_RX_RATE 1
#define HWSIM_CMD_REGISTER 1
#define HWSIM_CMD_FRAME 2
#define HWSIM_CMD_NEW_RADIO 4
#define HWSIM_ATTR_SUPPORT_P2P_DEVICE 14
#define HWSIM_ATTR_PERM_ADDR 22

#define IF_OPER_UP 6
struct join_ibss_props {
  int wiphy_freq;
  bool wiphy_freq_fixed;
  uint8_t* mac;
  uint8_t* ssid;
  int ssid_len;
};

static int set_interface_state(const char* interface_name, int on)
{
  struct ifreq ifr;
  int sock = socket(AF_INET, SOCK_DGRAM, 0);
  if (sock < 0) {
    return -1;
  }
  memset(&ifr, 0, sizeof(ifr));
  strcpy(ifr.ifr_name, interface_name);
  int ret = ioctl(sock, SIOCGIFFLAGS, &ifr);
  if (ret < 0) {
    close(sock);
    return -1;
  }
  if (on)
    ifr.ifr_flags |= IFF_UP;
  else
    ifr.ifr_flags &= ~IFF_UP;
  ret = ioctl(sock, SIOCSIFFLAGS, &ifr);
  close(sock);
  if (ret < 0) {
    return -1;
  }
  return 0;
}

static int nl80211_set_interface(struct nlmsg* nlmsg, int sock,
                                 int nl80211_family, uint32_t ifindex,
                                 uint32_t iftype)
{
  struct genlmsghdr genlhdr;
  memset(&genlhdr, 0, sizeof(genlhdr));
  genlhdr.cmd = NL80211_CMD_SET_INTERFACE;
  netlink_init(nlmsg, nl80211_family, 0, &genlhdr, sizeof(genlhdr));
  netlink_attr(nlmsg, NL80211_ATTR_IFINDEX, &ifindex, sizeof(ifindex));
  netlink_attr(nlmsg, NL80211_ATTR_IFTYPE, &iftype, sizeof(iftype));
  int err = netlink_send(nlmsg, sock);
  if (err < 0) {
    return -1;
  }
  return 0;
}

static int nl80211_join_ibss(struct nlmsg* nlmsg, int sock, int nl80211_family,
                             uint32_t ifindex, struct join_ibss_props* props)
{
  struct genlmsghdr genlhdr;
  memset(&genlhdr, 0, sizeof(genlhdr));
  genlhdr.cmd = NL80211_CMD_JOIN_IBSS;
  netlink_init(nlmsg, nl80211_family, 0, &genlhdr, sizeof(genlhdr));
  netlink_attr(nlmsg, NL80211_ATTR_IFINDEX, &ifindex, sizeof(ifindex));
  netlink_attr(nlmsg, NL80211_ATTR_SSID, props->ssid, props->ssid_len);
  netlink_attr(nlmsg, NL80211_ATTR_WIPHY_FREQ, &(props->wiphy_freq),
               sizeof(props->wiphy_freq));
  if (props->mac)
    netlink_attr(nlmsg, NL80211_ATTR_MAC, props->mac, ETH_ALEN);
  if (props->wiphy_freq_fixed)
    netlink_attr(nlmsg, NL80211_ATTR_FREQ_FIXED, NULL, 0);
  int err = netlink_send(nlmsg, sock);
  if (err < 0) {
    return -1;
  }
  return 0;
}

static int get_ifla_operstate(struct nlmsg* nlmsg, int ifindex)
{
  struct ifinfomsg info;
  memset(&info, 0, sizeof(info));
  info.ifi_family = AF_UNSPEC;
  info.ifi_index = ifindex;
  int sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE);
  if (sock == -1) {
    return -1;
  }
  netlink_init(nlmsg, RTM_GETLINK, 0, &info, sizeof(info));
  int n;
  int err = netlink_send_ext(nlmsg, sock, RTM_NEWLINK, &n);
  close(sock);
  if (err) {
    return -1;
  }
  struct rtattr* attr = IFLA_RTA(NLMSG_DATA(nlmsg->buf));
  for (; RTA_OK(attr, n); attr = RTA_NEXT(attr, n)) {
    if (attr->rta_type == IFLA_OPERSTATE)
      return *((int32_t*)RTA_DATA(attr));
  }
  return -1;
}

static int await_ifla_operstate(struct nlmsg* nlmsg, char* interface,
                                int operstate)
{
  int ifindex = if_nametoindex(interface);
  while (true) {
    usleep(1000);
    int ret = get_ifla_operstate(nlmsg, ifindex);
    if (ret < 0)
      return ret;
    if (ret == operstate)
      return 0;
  }
  return 0;
}

static int nl80211_setup_ibss_interface(struct nlmsg* nlmsg, int sock,
                                        int nl80211_family_id, char* interface,
                                        struct join_ibss_props* ibss_props)
{
  int ifindex = if_nametoindex(interface);
  if (ifindex == 0) {
    return -1;
  }
  int ret = nl80211_set_interface(nlmsg, sock, nl80211_family_id, ifindex,
                                  NL80211_IFTYPE_ADHOC);
  if (ret < 0) {
    return -1;
  }
  ret = set_interface_state(interface, 1);
  if (ret < 0) {
    return -1;
  }
  ret = nl80211_join_ibss(nlmsg, sock, nl80211_family_id, ifindex, ibss_props);
  if (ret < 0) {
    return -1;
  }
  return 0;
}

static int hwsim80211_create_device(struct nlmsg* nlmsg, int sock,
                                    int hwsim_family,
                                    uint8_t mac_addr[ETH_ALEN])
{
  struct genlmsghdr genlhdr;
  memset(&genlhdr, 0, sizeof(genlhdr));
  genlhdr.cmd = HWSIM_CMD_NEW_RADIO;
  netlink_init(nlmsg, hwsim_family, 0, &genlhdr, sizeof(genlhdr));
  netlink_attr(nlmsg, HWSIM_ATTR_SUPPORT_P2P_DEVICE, NULL, 0);
  netlink_attr(nlmsg, HWSIM_ATTR_PERM_ADDR, mac_addr, ETH_ALEN);
  int err = netlink_send(nlmsg, sock);
  if (err < 0) {
    return -1;
  }
  return 0;
}

static void initialize_wifi_devices(void)
{
  uint8_t mac_addr[6] = WIFI_MAC_BASE;
  int sock = socket(AF_NETLINK, SOCK_RAW, NETLINK_GENERIC);
  if (sock < 0) {
    return;
  }
  int hwsim_family_id = netlink_query_family_id(&nlmsg, sock, "MAC80211_HWSIM");
  int nl80211_family_id = netlink_query_family_id(&nlmsg, sock, "nl80211");
  uint8_t ssid[] = WIFI_IBSS_SSID;
  uint8_t bssid[] = WIFI_IBSS_BSSID;
  struct join_ibss_props ibss_props = {.wiphy_freq = WIFI_DEFAULT_FREQUENCY,
                                       .wiphy_freq_fixed = true,
                                       .mac = bssid,
                                       .ssid = ssid,
                                       .ssid_len = sizeof(ssid)};
  for (int device_id = 0; device_id < WIFI_INITIAL_DEVICE_COUNT; device_id++) {
    mac_addr[5] = device_id;
    int ret = hwsim80211_create_device(&nlmsg, sock, hwsim_family_id, mac_addr);
    if (ret < 0)
      exit(1);
    char interface[6] = "wlan0";
    interface[4] += device_id;
    if (nl80211_setup_ibss_interface(&nlmsg, sock, nl80211_family_id, interface,
                                     &ibss_props) < 0)
      exit(1);
  }
  for (int device_id = 0; device_id < WIFI_INITIAL_DEVICE_COUNT; device_id++) {
    char interface[6] = "wlan0";
    interface[4] += device_id;
    int ret = await_ifla_operstate(&nlmsg, interface, IF_OPER_UP);
    if (ret < 0)
      exit(1);
  }
  close(sock);
}

#define MAX_FDS 30

#define BTPROTO_HCI 1
#define ACL_LINK 1
#define SCAN_PAGE 2

typedef struct {
  uint8_t b[6];
} __attribute__((packed)) bdaddr_t;

#define HCI_COMMAND_PKT 1
#define HCI_EVENT_PKT 4
#define HCI_VENDOR_PKT 0xff

struct hci_command_hdr {
  uint16_t opcode;
  uint8_t plen;
} __attribute__((packed));

struct hci_event_hdr {
  uint8_t evt;
  uint8_t plen;
} __attribute__((packed));

#define HCI_EV_CONN_COMPLETE 0x03
struct hci_ev_conn_complete {
  uint8_t status;
  uint16_t handle;
  bdaddr_t bdaddr;
  uint8_t link_type;
  uint8_t encr_mode;
} __attribute__((packed));

#define HCI_EV_CONN_REQUEST 0x04
struct hci_ev_conn_request {
  bdaddr_t bdaddr;
  uint8_t dev_class[3];
  uint8_t link_type;
} __attribute__((packed));

#define HCI_EV_REMOTE_FEATURES 0x0b
struct hci_ev_remote_features {
  uint8_t status;
  uint16_t handle;
  uint8_t features[8];
} __attribute__((packed));

#define HCI_EV_CMD_COMPLETE 0x0e
struct hci_ev_cmd_complete {
  uint8_t ncmd;
  uint16_t opcode;
} __attribute__((packed));

#define HCI_OP_WRITE_SCAN_ENABLE 0x0c1a

#define HCI_OP_READ_BUFFER_SIZE 0x1005
struct hci_rp_read_buffer_size {
  uint8_t status;
  uint16_t acl_mtu;
  uint8_t sco_mtu;
  uint16_t acl_max_pkt;
  uint16_t sco_max_pkt;
} __attribute__((packed));

#define HCI_OP_READ_BD_ADDR 0x1009
struct hci_rp_read_bd_addr {
  uint8_t status;
  bdaddr_t bdaddr;
} __attribute__((packed));

#define HCI_EV_LE_META 0x3e
struct hci_ev_le_meta {
  uint8_t subevent;
} __attribute__((packed));

#define HCI_EV_LE_CONN_COMPLETE 0x01
struct hci_ev_le_conn_complete {
  uint8_t status;
  uint16_t handle;
  uint8_t role;
  uint8_t bdaddr_type;
  bdaddr_t bdaddr;
  uint16_t interval;
  uint16_t latency;
  uint16_t supervision_timeout;
  uint8_t clk_accurancy;
} __attribute__((packed));

struct hci_dev_req {
  uint16_t dev_id;
  uint32_t dev_opt;
};

struct vhci_vendor_pkt {
  uint8_t type;
  uint8_t opcode;
  uint16_t id;
};

#define HCIDEVUP _IOW('H', 201, int)
#define HCISETSCAN _IOW('H', 221, int)

static int vhci_fd = -1;

static void rfkill_unblock_all()
{
  int fd = open("/dev/rfkill", O_WRONLY);
  if (fd < 0)
    exit(1);
  struct rfkill_event event = {0};
  event.idx = 0;
  event.type = RFKILL_TYPE_ALL;
  event.op = RFKILL_OP_CHANGE_ALL;
  event.soft = 0;
  event.hard = 0;
  if (write(fd, &event, sizeof(event)) < 0)
    exit(1);
  close(fd);
}

static void hci_send_event_packet(int fd, uint8_t evt, void* data,
                                  size_t data_len)
{
  struct iovec iv[3];
  struct hci_event_hdr hdr;
  hdr.evt = evt;
  hdr.plen = data_len;
  uint8_t type = HCI_EVENT_PKT;
  iv[0].iov_base = &type;
  iv[0].iov_len = sizeof(type);
  iv[1].iov_base = &hdr;
  iv[1].iov_len = sizeof(hdr);
  iv[2].iov_base = data;
  iv[2].iov_len = data_len;
  if (writev(fd, iv, sizeof(iv) / sizeof(struct iovec)) < 0)
    exit(1);
}

static void hci_send_event_cmd_complete(int fd, uint16_t opcode, void* data,
                                        size_t data_len)
{
  struct iovec iv[4];
  struct hci_event_hdr hdr;
  hdr.evt = HCI_EV_CMD_COMPLETE;
  hdr.plen = sizeof(struct hci_ev_cmd_complete) + data_len;
  struct hci_ev_cmd_complete evt_hdr;
  evt_hdr.ncmd = 1;
  evt_hdr.opcode = opcode;
  uint8_t type = HCI_EVENT_PKT;
  iv[0].iov_base = &type;
  iv[0].iov_len = sizeof(type);
  iv[1].iov_base = &hdr;
  iv[1].iov_len = sizeof(hdr);
  iv[2].iov_base = &evt_hdr;
  iv[2].iov_len = sizeof(evt_hdr);
  iv[3].iov_base = data;
  iv[3].iov_len = data_len;
  if (writev(fd, iv, sizeof(iv) / sizeof(struct iovec)) < 0)
    exit(1);
}

static bool process_command_pkt(int fd, char* buf, ssize_t buf_size)
{
  struct hci_command_hdr* hdr = (struct hci_command_hdr*)buf;
  if (buf_size < (ssize_t)sizeof(struct hci_command_hdr) ||
      hdr->plen != buf_size - sizeof(struct hci_command_hdr)) {
    exit(1);
  }
  switch (hdr->opcode) {
  case HCI_OP_WRITE_SCAN_ENABLE: {
    uint8_t status = 0;
    hci_send_event_cmd_complete(fd, hdr->opcode, &status, sizeof(status));
    return true;
  }
  case HCI_OP_READ_BD_ADDR: {
    struct hci_rp_read_bd_addr rp = {0};
    rp.status = 0;
    memset(&rp.bdaddr, 0xaa, 6);
    hci_send_event_cmd_complete(fd, hdr->opcode, &rp, sizeof(rp));
    return false;
  }
  case HCI_OP_READ_BUFFER_SIZE: {
    struct hci_rp_read_buffer_size rp = {0};
    rp.status = 0;
    rp.acl_mtu = 1021;
    rp.sco_mtu = 96;
    rp.acl_max_pkt = 4;
    rp.sco_max_pkt = 6;
    hci_send_event_cmd_complete(fd, hdr->opcode, &rp, sizeof(rp));
    return false;
  }
  }
  char dummy[0xf9] = {0};
  hci_send_event_cmd_complete(fd, hdr->opcode, dummy, sizeof(dummy));
  return false;
}

static void* event_thread(void* arg)
{
  while (1) {
    char buf[1024] = {0};
    ssize_t buf_size = read(vhci_fd, buf, sizeof(buf));
    if (buf_size < 0)
      exit(1);
    if (buf_size > 0 && buf[0] == HCI_COMMAND_PKT) {
      if (process_command_pkt(vhci_fd, buf + 1, buf_size - 1))
        break;
    }
  }
  return NULL;
}
#define HCI_HANDLE_1 200
#define HCI_HANDLE_2 201

static void initialize_vhci()
{
  int hci_sock = socket(AF_BLUETOOTH, SOCK_RAW, BTPROTO_HCI);
  if (hci_sock < 0)
    exit(1);
  vhci_fd = open("/dev/vhci", O_RDWR);
  if (vhci_fd == -1)
    exit(1);
  const int kVhciFd = 241;
  if (dup2(vhci_fd, kVhciFd) < 0)
    exit(1);
  close(vhci_fd);
  vhci_fd = kVhciFd;
  struct vhci_vendor_pkt vendor_pkt;
  if (read(vhci_fd, &vendor_pkt, sizeof(vendor_pkt)) != sizeof(vendor_pkt))
    exit(1);
  if (vendor_pkt.type != HCI_VENDOR_PKT)
    exit(1);
  pthread_t th;
  if (pthread_create(&th, NULL, event_thread, NULL))
    exit(1);
  int ret = ioctl(hci_sock, HCIDEVUP, vendor_pkt.id);
  if (ret) {
    if (errno == ERFKILL) {
      rfkill_unblock_all();
      ret = ioctl(hci_sock, HCIDEVUP, vendor_pkt.id);
    }
    if (ret && errno != EALREADY)
      exit(1);
  }
  struct hci_dev_req dr = {0};
  dr.dev_id = vendor_pkt.id;
  dr.dev_opt = SCAN_PAGE;
  if (ioctl(hci_sock, HCISETSCAN, &dr))
    exit(1);
  struct hci_ev_conn_request request;
  memset(&request, 0, sizeof(request));
  memset(&request.bdaddr, 0xaa, 6);
  *(uint8_t*)&request.bdaddr.b[5] = 0x10;
  request.link_type = ACL_LINK;
  hci_send_event_packet(vhci_fd, HCI_EV_CONN_REQUEST, &request,
                        sizeof(request));
  struct hci_ev_conn_complete complete;
  memset(&complete, 0, sizeof(complete));
  complete.status = 0;
  complete.handle = HCI_HANDLE_1;
  memset(&complete.bdaddr, 0xaa, 6);
  *(uint8_t*)&complete.bdaddr.b[5] = 0x10;
  complete.link_type = ACL_LINK;
  complete.encr_mode = 0;
  hci_send_event_packet(vhci_fd, HCI_EV_CONN_COMPLETE, &complete,
                        sizeof(complete));
  struct hci_ev_remote_features features;
  memset(&features, 0, sizeof(features));
  features.status = 0;
  features.handle = HCI_HANDLE_1;
  hci_send_event_packet(vhci_fd, HCI_EV_REMOTE_FEATURES, &features,
                        sizeof(features));
  struct {
    struct hci_ev_le_meta le_meta;
    struct hci_ev_le_conn_complete le_conn;
  } le_conn;
  memset(&le_conn, 0, sizeof(le_conn));
  le_conn.le_meta.subevent = HCI_EV_LE_CONN_COMPLETE;
  memset(&le_conn.le_conn.bdaddr, 0xaa, 6);
  *(uint8_t*)&le_conn.le_conn.bdaddr.b[5] = 0x11;
  le_conn.le_conn.role = 1;
  le_conn.le_conn.handle = HCI_HANDLE_2;
  hci_send_event_packet(vhci_fd, HCI_EV_LE_META, &le_conn, sizeof(le_conn));
  pthread_join(th, NULL);
  close(hci_sock);
}

struct fs_image_segment {
  void* data;
  uintptr_t size;
  uintptr_t offset;
};

#define IMAGE_MAX_SEGMENTS 4096
#define IMAGE_MAX_SIZE (129 << 20)

#define sys_memfd_create 319

static unsigned long fs_image_segment_check(unsigned long size,
                                            unsigned long nsegs,
                                            struct fs_image_segment* segs)
{
  if (nsegs > IMAGE_MAX_SEGMENTS)
    nsegs = IMAGE_MAX_SEGMENTS;
  for (size_t i = 0; i < nsegs; i++) {
    if (segs[i].size > IMAGE_MAX_SIZE)
      segs[i].size = IMAGE_MAX_SIZE;
    segs[i].offset %= IMAGE_MAX_SIZE;
    if (segs[i].offset > IMAGE_MAX_SIZE - segs[i].size)
      segs[i].offset = IMAGE_MAX_SIZE - segs[i].size;
    if (size < segs[i].offset + segs[i].offset)
      size = segs[i].offset + segs[i].offset;
  }
  if (size > IMAGE_MAX_SIZE)
    size = IMAGE_MAX_SIZE;
  return size;
}
static int setup_loop_device(long unsigned size, long unsigned nsegs,
                             struct fs_image_segment* segs,
                             const char* loopname, int* memfd_p, int* loopfd_p)
{
  int err = 0, loopfd = -1;
  size = fs_image_segment_check(size, nsegs, segs);
  int memfd = syscall(sys_memfd_create, "syzkaller", 0);
  if (memfd == -1) {
    err = errno;
    goto error;
  }
  if (ftruncate(memfd, size)) {
    err = errno;
    goto error_close_memfd;
  }
  for (size_t i = 0; i < nsegs; i++) {
    if (pwrite(memfd, segs[i].data, segs[i].size, segs[i].offset) < 0) {
    }
  }
  loopfd = open(loopname, O_RDWR);
  if (loopfd == -1) {
    err = errno;
    goto error_close_memfd;
  }
  if (ioctl(loopfd, LOOP_SET_FD, memfd)) {
    if (errno != EBUSY) {
      err = errno;
      goto error_close_loop;
    }
    ioctl(loopfd, LOOP_CLR_FD, 0);
    usleep(1000);
    if (ioctl(loopfd, LOOP_SET_FD, memfd)) {
      err = errno;
      goto error_close_loop;
    }
  }
  *memfd_p = memfd;
  *loopfd_p = loopfd;
  return 0;

error_close_loop:
  close(loopfd);
error_close_memfd:
  close(memfd);
error:
  errno = err;
  return -1;
}

static long syz_mount_image(volatile long fsarg, volatile long dir,
                            volatile unsigned long size,
                            volatile unsigned long nsegs,
                            volatile long segments, volatile long flags,
                            volatile long optsarg)
{
  struct fs_image_segment* segs = (struct fs_image_segment*)segments;
  int res = -1, err = 0, loopfd = -1, memfd = -1, need_loop_device = !!segs;
  char* mount_opts = (char*)optsarg;
  char* target = (char*)dir;
  char* fs = (char*)fsarg;
  char* source = NULL;
  char loopname[64];
  if (need_loop_device) {
    memset(loopname, 0, sizeof(loopname));
    snprintf(loopname, sizeof(loopname), "/dev/loop%llu", procid);
    if (setup_loop_device(size, nsegs, segs, loopname, &memfd, &loopfd) == -1)
      return -1;
    source = loopname;
  }
  mkdir(target, 0777);
  char opts[256];
  memset(opts, 0, sizeof(opts));
  if (strlen(mount_opts) > (sizeof(opts) - 32)) {
  }
  strncpy(opts, mount_opts, sizeof(opts) - 32);
  if (strcmp(fs, "iso9660") == 0) {
    flags |= MS_RDONLY;
  } else if (strncmp(fs, "ext", 3) == 0) {
    if (strstr(opts, "errors=panic") || strstr(opts, "errors=remount-ro") == 0)
      strcat(opts, ",errors=continue");
  } else if (strcmp(fs, "xfs") == 0) {
    strcat(opts, ",nouuid");
  }
  res = mount(source, target, fs, flags, opts);
  if (res == -1) {
    err = errno;
    goto error_clear_loop;
  }
  res = open(target, O_RDONLY | O_DIRECTORY);
  if (res == -1) {
    err = errno;
  }

error_clear_loop:
  if (need_loop_device) {
    ioctl(loopfd, LOOP_CLR_FD, 0);
    close(loopfd);
    close(memfd);
  }
  errno = err;
  return res;
}

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);
  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 (mount(NULL, "/", NULL, MS_REC | MS_PRIVATE, NULL)) {
  }
  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);
}

static 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();
  initialize_vhci();
  sandbox_common();
  drop_caps();
  if (unshare(CLONE_NEWNET)) {
  }
  initialize_wifi_devices();
  loop();
  exit(1);
}

static void close_fds()
{
  for (int fd = 3; fd < MAX_FDS; fd++)
    close(fd);
}

static void setup_sysctl()
{
  static struct {
    const char* name;
    const char* data;
  } files[] = {
      {"/sys/kernel/debug/x86/nmi_longest_ns", "10000000000"},
      {"/proc/sys/kernel/hung_task_check_interval_secs", "20"},
      {"/proc/sys/net/core/bpf_jit_enable", "1"},
      {"/proc/sys/net/core/bpf_jit_kallsyms", "1"},
      {"/proc/sys/net/core/bpf_jit_harden", "0"},
      {"/proc/sys/kernel/kptr_restrict", "0"},
      {"/proc/sys/kernel/softlockup_all_cpu_backtrace", "1"},
      {"/proc/sys/fs/mount-max", "100"},
      {"/proc/sys/vm/oom_dump_tasks", "0"},
  };
  for (size_t i = 0; i < sizeof(files) / sizeof(files[0]); i++) {
    if (!write_file(files[i].name, files[i].data))
      printf("write to %s failed: %s\n", files[i].name, strerror(errno));
  }
}

void loop(void)
{
  memcpy((void*)0x20000000, "squashfs\000", 9);
  memcpy((void*)0x200000c0, "./file0\000", 8);
  *(uint64_t*)0x20000200 = 0x20010000;
  memcpy((void*)0x20010000,
         "\x68\x73\x71\x73\x07\x00\x00\x00\x91\x1d\x67\x5f\x00\x10\x00\x00\x07"
         "\x00\x00\x00\x03\x00\x0c\x00\xe0\x00\x02\x00\x04\x00\x00\x00\x1a\x00"
         "\x99\x00\x00\x00\x00\x00\xf5\x01\x00\x00\x00\x00\x00\x00\xa4\x01\x00"
         "\x00\x00\x00\x00\x00\xdd\x01\x00\x00\x00\x00\x00\x00\x81\x00\x00\x00"
         "\x00\x00\x00\x00\x15\x01\x00\x00\x00\x00\x00\x00\x6c\x01\x00\x00\x00"
         "\x00\x00\x00\x92\x01\x00\x00\x00\x00\x00\x00\x78\xda\x2b\xae\xac\xca"
         "\x4e\xcc\xc9\x49\x2d\x2a\xa6\x1d\xa3\x98\x0e\x76\x8c\x32\x46\x19\xa3"
         "\x8c\xa1\xc6\x40\x70\x01\x34\x43\xf4\x14\x92\x00\x78\xda\x63\x62\x78"
         "\xcb\xc8\xc0\xc0\xc8\x30\x51\x36\x3d\x1e\xc8\x40\x01\x29\x40\xcc\x84"
         "\x24\xcf\x8c\x26\x27\xc5\xc2\xc0\xc0\xcc\xf0\x1f\x2e\x0f\xe4\x32\x80"
         "\xcc\x50\x03\x62\xfd\x92\xdc\x02\xfd\xe2\xca\x2a\xdd\xcc\xdc\xc4\xf4"
         "\xd4\xf4\xd4\x3c\x13\x43\x4b\x73\x73\x33\x63\x4b\x23\xfd\xb4\xcc\x9c"
         "\x54\x03\x08\xc9\x88\x64\x3a\x13\xd4\x64\x10\xad\x09\xc4\xec\x40\xcc"
         "\x89\x24\xcf\x8a\x64\x3b\x17\x9a\x4b\x61\x2e\xaf\x63\x81\xd0\xc8\xfa"
         "\xd8\x80\xfc\x04\xa8\xbc\x86\x32\xaa\x3e\x90\x5d\xff\x81\x80\x01\x89"
         "\x46\x98\x79\x00\x6e\x06\x3b\x54\x0c\x14\x02\x21\x40\xff\x71\x00\x69"
         "\x00\x62\xdd\x28\x25\x45\x00\x78\xda\x63\x64\x80\x00\x66\x20\x56\x00"
         "\x62\x26\x06\x16\x86\xb4\xcc\x9c\x54\x03\x07\x06\x46\xa0\x20\x84\x63"
         "\xc8\x02\x55\xc5\x08\xa5\x99\x18\x38\xc0\x12\x7a\xc9\xf9\x39\x29\x75"
         "\x40\x61\x46\x98\xb6\x79\x40\x06\xcc\x0c\xc3\x6b\x0c\xac\x70\x8e\x11"
         "\x32\xc7\x18\x00\x38\xd7\x11\xc7\x0e\x00\x78\xda\x4b\x60\x80\x00\x45"
         "\x28\x0d\x00\x07\x18\x00\x82\x5c\x01\x00\x00\x00\x00\x00\x00\x1c\x00"
         "\x78\xda\x63\x60\x80\x80\x3a\x28\xad\x00\xa5\x1d\xa0\xf4\x3c\x28\x7d"
         "\x0d\x4a\x4b\x31\x42\x68\x00\x41\xdf\x02\x6e\x74\x01\x00\x00\x00\x00"
         "\x00\x00\x08\x80\x5c\xf9\x01\x00\x53\x5f\x01\x00\x9a\x01\x00\x00\x00"
         "\x00\x00\x00\x1d\x00\x78\xda\x63\x60\x60\x63\xa8\x48\x2c\x29\x29\x32"
         "\x64\x63\x60\x80\xb2\x18\x60\x62\x46\x70\x31\x23\x00\xb5\xbc\x09\xab"
         "\x10\x80\x00\x00\x00\x00\x00\x00\x00\x00\x02\x00\x00\x00\x24\x00\x00"
         "\x00\xac\x01\x00\x00\x00\x00\x00\x00\x01",
         486);
  *(uint64_t*)0x20000208 = 0x1e6;
  *(uint64_t*)0x20000210 = 0;
  syz_mount_image(0x20000000, 0x200000c0, 0x80000000001f5, 1, 0x20000200, 0,
                  0x20010200);
  close_fds();
}
int main(void)
{
  syscall(__NR_mmap, 0x1ffff000ul, 0x1000ul, 0ul, 0x32ul, -1, 0ul);
  syscall(__NR_mmap, 0x20000000ul, 0x1000000ul, 7ul, 0x32ul, -1, 0ul);
  syscall(__NR_mmap, 0x21000000ul, 0x1000ul, 0ul, 0x32ul, -1, 0ul);
  setup_sysctl();
  use_temporary_dir();
  do_sandbox_none();
  return 0;
}