// https://syzkaller.appspot.com/bug?id=6c137bde6efa724b85a59042225145a547947eb0
// autogenerated by syzkaller (https://github.com/google/syzkaller)

#define _GNU_SOURCE

#include <dirent.h>
#include <endian.h>
#include <errno.h>
#include <fcntl.h>
#include <pthread.h>
#include <signal.h>
#include <stdarg.h>
#include <stdbool.h>
#include <stddef.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/stat.h>
#include <sys/syscall.h>
#include <sys/types.h>
#include <sys/wait.h>
#include <time.h>
#include <unistd.h>

#include <linux/futex.h>
#include <linux/usb/ch9.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 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 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;
}

#define USB_DEBUG 0

#define USB_MAX_IFACE_NUM 4
#define USB_MAX_EP_NUM 32

struct usb_iface_index {
  struct usb_interface_descriptor* iface;
  struct usb_endpoint_descriptor* eps[USB_MAX_EP_NUM];
  unsigned eps_num;
};

struct usb_device_index {
  struct usb_device_descriptor* dev;
  struct usb_config_descriptor* config;
  unsigned config_length;
  struct usb_iface_index ifaces[USB_MAX_IFACE_NUM];
  unsigned ifaces_num;
};

static bool parse_usb_descriptor(char* buffer, size_t length,
                                 struct usb_device_index* index)
{
  if (length < sizeof(*index->dev) + sizeof(*index->config))
    return false;
  memset(index, 0, sizeof(*index));
  index->dev = (struct usb_device_descriptor*)buffer;
  index->config = (struct usb_config_descriptor*)(buffer + sizeof(*index->dev));
  index->config_length = length - sizeof(*index->dev);
  size_t offset = 0;
  while (true) {
    if (offset + 1 >= length)
      break;
    uint8_t desc_length = buffer[offset];
    uint8_t desc_type = buffer[offset + 1];
    if (desc_length <= 2)
      break;
    if (offset + desc_length > length)
      break;
    if (desc_type == USB_DT_INTERFACE &&
        index->ifaces_num < USB_MAX_IFACE_NUM) {
      struct usb_interface_descriptor* iface =
          (struct usb_interface_descriptor*)(buffer + offset);
      index->ifaces[index->ifaces_num++].iface = iface;
    }
    if (desc_type == USB_DT_ENDPOINT && index->ifaces_num > 0) {
      struct usb_iface_index* iface = &index->ifaces[index->ifaces_num - 1];
      if (iface->eps_num < USB_MAX_EP_NUM)
        iface->eps[iface->eps_num++] =
            (struct usb_endpoint_descriptor*)(buffer + offset);
    }
    offset += desc_length;
  }
  return true;
}

enum usb_fuzzer_event_type {
  USB_FUZZER_EVENT_INVALID,
  USB_FUZZER_EVENT_CONNECT,
  USB_FUZZER_EVENT_DISCONNECT,
  USB_FUZZER_EVENT_SUSPEND,
  USB_FUZZER_EVENT_RESUME,
  USB_FUZZER_EVENT_CONTROL,
};

struct usb_fuzzer_event {
  uint32_t type;
  uint32_t length;
  char data[0];
};

struct usb_fuzzer_init {
  uint64_t speed;
  const char* driver_name;
  const char* device_name;
};

struct usb_fuzzer_ep_io {
  uint16_t ep;
  uint16_t flags;
  uint32_t length;
  char data[0];
};

#define USB_FUZZER_IOCTL_INIT _IOW('U', 0, struct usb_fuzzer_init)
#define USB_FUZZER_IOCTL_RUN _IO('U', 1)
#define USB_FUZZER_IOCTL_EVENT_FETCH _IOR('U', 2, struct usb_fuzzer_event)
#define USB_FUZZER_IOCTL_EP0_WRITE _IOW('U', 3, struct usb_fuzzer_ep_io)
#define USB_FUZZER_IOCTL_EP0_READ _IOWR('U', 4, struct usb_fuzzer_ep_io)
#define USB_FUZZER_IOCTL_EP_ENABLE _IOW('U', 5, struct usb_endpoint_descriptor)
#define USB_FUZZER_IOCTL_EP_WRITE _IOW('U', 7, struct usb_fuzzer_ep_io)
#define USB_FUZZER_IOCTL_EP_READ _IOWR('U', 8, struct usb_fuzzer_ep_io)
#define USB_FUZZER_IOCTL_CONFIGURE _IO('U', 9)
#define USB_FUZZER_IOCTL_VBUS_DRAW _IOW('U', 10, uint32_t)

int usb_fuzzer_open()
{
  return open("/sys/kernel/debug/usb-fuzzer", O_RDWR);
}

int usb_fuzzer_init(int fd, uint32_t speed, const char* driver,
                    const char* device)
{
  struct usb_fuzzer_init arg;
  arg.speed = speed;
  arg.driver_name = driver;
  arg.device_name = device;
  return ioctl(fd, USB_FUZZER_IOCTL_INIT, &arg);
}

int usb_fuzzer_run(int fd)
{
  return ioctl(fd, USB_FUZZER_IOCTL_RUN, 0);
}

int usb_fuzzer_event_fetch(int fd, struct usb_fuzzer_event* event)
{
  return ioctl(fd, USB_FUZZER_IOCTL_EVENT_FETCH, event);
}

int usb_fuzzer_ep0_write(int fd, struct usb_fuzzer_ep_io* io)
{
  return ioctl(fd, USB_FUZZER_IOCTL_EP0_WRITE, io);
}

int usb_fuzzer_ep0_read(int fd, struct usb_fuzzer_ep_io* io)
{
  return ioctl(fd, USB_FUZZER_IOCTL_EP0_READ, io);
}

int usb_fuzzer_ep_write(int fd, struct usb_fuzzer_ep_io* io)
{
  return ioctl(fd, USB_FUZZER_IOCTL_EP_WRITE, io);
}

int usb_fuzzer_ep_read(int fd, struct usb_fuzzer_ep_io* io)
{
  return ioctl(fd, USB_FUZZER_IOCTL_EP_READ, io);
}

int usb_fuzzer_ep_enable(int fd, struct usb_endpoint_descriptor* desc)
{
  return ioctl(fd, USB_FUZZER_IOCTL_EP_ENABLE, desc);
}

int usb_fuzzer_configure(int fd)
{
  return ioctl(fd, USB_FUZZER_IOCTL_CONFIGURE, 0);
}

int usb_fuzzer_vbus_draw(int fd, uint32_t power)
{
  return ioctl(fd, USB_FUZZER_IOCTL_VBUS_DRAW, power);
}

#define USB_MAX_PACKET_SIZE 1024

struct usb_fuzzer_control_event {
  struct usb_fuzzer_event inner;
  struct usb_ctrlrequest ctrl;
  char data[USB_MAX_PACKET_SIZE];
};

struct usb_fuzzer_ep_io_data {
  struct usb_fuzzer_ep_io inner;
  char data[USB_MAX_PACKET_SIZE];
};

struct vusb_connect_string_descriptor {
  uint32_t len;
  char* str;
} __attribute__((packed));

struct vusb_connect_descriptors {
  uint32_t qual_len;
  char* qual;
  uint32_t bos_len;
  char* bos;
  uint32_t strs_len;
  struct vusb_connect_string_descriptor strs[0];
} __attribute__((packed));

static const char default_string[] = {8, USB_DT_STRING, 's', 0, 'y', 0, 'z', 0};

static const char default_lang_id[] = {4, USB_DT_STRING, 0x09, 0x04};

static bool lookup_connect_response(struct vusb_connect_descriptors* descs,
                                    struct usb_device_index* index,
                                    struct usb_ctrlrequest* ctrl,
                                    char** response_data,
                                    uint32_t* response_length)
{
  uint8_t str_idx;
  switch (ctrl->bRequestType & USB_TYPE_MASK) {
  case USB_TYPE_STANDARD:
    switch (ctrl->bRequest) {
    case USB_REQ_GET_DESCRIPTOR:
      switch (ctrl->wValue >> 8) {
      case USB_DT_DEVICE:
        *response_data = (char*)index->dev;
        *response_length = sizeof(*index->dev);
        return true;
      case USB_DT_CONFIG:
        *response_data = (char*)index->config;
        *response_length = index->config_length;
        return true;
      case USB_DT_STRING:
        str_idx = (uint8_t)ctrl->wValue;
        if (descs && str_idx < descs->strs_len) {
          *response_data = descs->strs[str_idx].str;
          *response_length = descs->strs[str_idx].len;
          return true;
        }
        if (str_idx == 0) {
          *response_data = (char*)&default_lang_id[0];
          *response_length = default_lang_id[0];
          return true;
        }
        *response_data = (char*)&default_string[0];
        *response_length = default_string[0];
        return true;
      case USB_DT_BOS:
        *response_data = descs->bos;
        *response_length = descs->bos_len;
        return true;
      case USB_DT_DEVICE_QUALIFIER:
        if (!descs->qual) {
          struct usb_qualifier_descriptor* qual =
              (struct usb_qualifier_descriptor*)response_data;
          qual->bLength = sizeof(*qual);
          qual->bDescriptorType = USB_DT_DEVICE_QUALIFIER;
          qual->bcdUSB = index->dev->bcdUSB;
          qual->bDeviceClass = index->dev->bDeviceClass;
          qual->bDeviceSubClass = index->dev->bDeviceSubClass;
          qual->bDeviceProtocol = index->dev->bDeviceProtocol;
          qual->bMaxPacketSize0 = index->dev->bMaxPacketSize0;
          qual->bNumConfigurations = index->dev->bNumConfigurations;
          qual->bRESERVED = 0;
          *response_length = sizeof(*qual);
          return true;
        }
        *response_data = descs->qual;
        *response_length = descs->qual_len;
        return true;
      default:
        exit(1);
        return false;
      }
      break;
    default:
      exit(1);
      return false;
    }
    break;
  default:
    exit(1);
    return false;
  }
  return false;
}

static volatile long syz_usb_connect(volatile long a0, volatile long a1,
                                     volatile long a2, volatile long a3)
{
  uint64_t speed = a0;
  uint64_t dev_len = a1;
  char* dev = (char*)a2;
  struct vusb_connect_descriptors* descs = (struct vusb_connect_descriptors*)a3;
  if (!dev) {
    return -1;
  }
  struct usb_device_index index;
  memset(&index, 0, sizeof(index));
  int rv = 0;
  rv = parse_usb_descriptor(dev, dev_len, &index);
  if (!rv) {
    return rv;
  }
  int fd = usb_fuzzer_open();
  if (fd < 0) {
    return fd;
  }
  char device[32];
  sprintf(&device[0], "dummy_udc.%llu", procid);
  rv = usb_fuzzer_init(fd, speed, "dummy_udc", &device[0]);
  if (rv < 0) {
    return rv;
  }
  rv = usb_fuzzer_run(fd);
  if (rv < 0) {
    return rv;
  }
  bool done = false;
  while (!done) {
    struct usb_fuzzer_control_event event;
    event.inner.type = 0;
    event.inner.length = sizeof(event.ctrl);
    rv = usb_fuzzer_event_fetch(fd, (struct usb_fuzzer_event*)&event);
    if (rv < 0) {
      return rv;
    }
    if (event.inner.type != USB_FUZZER_EVENT_CONTROL)
      continue;
    bool response_found = false;
    char* response_data = NULL;
    uint32_t response_length = 0;
    if (event.ctrl.bRequestType & USB_DIR_IN) {
      response_found = lookup_connect_response(
          descs, &index, &event.ctrl, &response_data, &response_length);
      if (!response_found) {
        return -1;
      }
    } else {
      if ((event.ctrl.bRequestType & USB_TYPE_MASK) != USB_TYPE_STANDARD ||
          event.ctrl.bRequest != USB_REQ_SET_CONFIGURATION) {
        exit(1);
        return -1;
      }
      done = true;
    }
    if (done) {
      rv = usb_fuzzer_vbus_draw(fd, index.config->bMaxPower);
      if (rv < 0) {
        return rv;
      }
      rv = usb_fuzzer_configure(fd);
      if (rv < 0) {
        return rv;
      }
      unsigned ep;
      for (ep = 0; ep < index.ifaces[0].eps_num; ep++) {
        rv = usb_fuzzer_ep_enable(fd, index.ifaces[0].eps[ep]);
        if (rv < 0) {
        } else {
        }
      }
    }
    struct usb_fuzzer_ep_io_data response;
    response.inner.ep = 0;
    response.inner.flags = 0;
    if (response_length > sizeof(response.data))
      response_length = 0;
    if (event.ctrl.wLength < response_length)
      response_length = event.ctrl.wLength;
    response.inner.length = response_length;
    if (response_data)
      memcpy(&response.data[0], response_data, response_length);
    else
      memset(&response.data[0], 0, response_length);
    if (event.ctrl.bRequestType & USB_DIR_IN) {
      rv = usb_fuzzer_ep0_write(fd, (struct usb_fuzzer_ep_io*)&response);
    } else {
      rv = usb_fuzzer_ep0_read(fd, (struct usb_fuzzer_ep_io*)&response);
    }
    if (rv < 0) {
      return rv;
    }
  }
  sleep_ms(200);
  return fd;
}

struct vusb_descriptor {
  uint8_t req_type;
  uint8_t desc_type;
  uint32_t len;
  char data[0];
} __attribute__((packed));

struct vusb_descriptors {
  uint32_t len;
  struct vusb_descriptor* generic;
  struct vusb_descriptor* descs[0];
} __attribute__((packed));

struct vusb_response {
  uint8_t type;
  uint8_t req;
  uint32_t len;
  char data[0];
} __attribute__((packed));

struct vusb_responses {
  uint32_t len;
  struct vusb_response* generic;
  struct vusb_response* resps[0];
} __attribute__((packed));

static bool lookup_control_response(struct vusb_descriptors* descs,
                                    struct vusb_responses* resps,
                                    struct usb_ctrlrequest* ctrl,
                                    char** response_data,
                                    uint32_t* response_length)
{
  int descs_num = 0;
  int resps_num = 0;
  if (descs)
    descs_num = (descs->len - offsetof(struct vusb_descriptors, descs)) /
                sizeof(descs->descs[0]);
  if (resps)
    resps_num = (resps->len - offsetof(struct vusb_responses, resps)) /
                sizeof(resps->resps[0]);
  uint8_t req = ctrl->bRequest;
  uint8_t req_type = ctrl->bRequestType & USB_TYPE_MASK;
  uint8_t desc_type = ctrl->wValue >> 8;
  if (req == USB_REQ_GET_DESCRIPTOR) {
    int i;
    for (i = 0; i < descs_num; i++) {
      struct vusb_descriptor* desc = descs->descs[i];
      if (!desc)
        continue;
      if (desc->req_type == req_type && desc->desc_type == desc_type) {
        *response_length = desc->len;
        if (*response_length != 0)
          *response_data = &desc->data[0];
        else
          *response_data = NULL;
        return true;
      }
    }
    if (descs && descs->generic) {
      *response_data = &descs->generic->data[0];
      *response_length = descs->generic->len;
      return true;
    }
  } else {
    int i;
    for (i = 0; i < resps_num; i++) {
      struct vusb_response* resp = resps->resps[i];
      if (!resp)
        continue;
      if (resp->type == req_type && resp->req == req) {
        *response_length = resp->len;
        if (*response_length != 0)
          *response_data = &resp->data[0];
        else
          *response_data = NULL;
        return true;
      }
    }
    if (resps && resps->generic) {
      *response_data = &resps->generic->data[0];
      *response_length = resps->generic->len;
      return true;
    }
  }
  return false;
}

static volatile long syz_usb_control_io(volatile long a0, volatile long a1,
                                        volatile long a2)
{
  int fd = a0;
  struct vusb_descriptors* descs = (struct vusb_descriptors*)a1;
  struct vusb_responses* resps = (struct vusb_responses*)a2;
  struct usb_fuzzer_control_event event;
  event.inner.type = 0;
  event.inner.length = USB_MAX_PACKET_SIZE;
  int rv = usb_fuzzer_event_fetch(fd, (struct usb_fuzzer_event*)&event);
  if (rv < 0) {
    return rv;
  }
  if (event.inner.type != USB_FUZZER_EVENT_CONTROL) {
    return -1;
  }
  bool response_found = false;
  char* response_data = NULL;
  uint32_t response_length = 0;
  if ((event.ctrl.bRequestType & USB_DIR_IN) && event.ctrl.wLength) {
    response_found = lookup_control_response(descs, resps, &event.ctrl,
                                             &response_data, &response_length);
    if (!response_found) {
      return -1;
    }
  } else {
    response_length = event.ctrl.wLength;
  }
  struct usb_fuzzer_ep_io_data response;
  response.inner.ep = 0;
  response.inner.flags = 0;
  if (response_length > sizeof(response.data))
    response_length = 0;
  if (event.ctrl.wLength < response_length)
    response_length = event.ctrl.wLength;
  if ((event.ctrl.bRequestType & USB_DIR_IN) && !event.ctrl.wLength) {
    response_length = USB_MAX_PACKET_SIZE;
  }
  response.inner.length = response_length;
  if (response_data)
    memcpy(&response.data[0], response_data, response_length);
  else
    memset(&response.data[0], 0, response_length);
  if ((event.ctrl.bRequestType & USB_DIR_IN) && event.ctrl.wLength) {
    rv = usb_fuzzer_ep0_write(fd, (struct usb_fuzzer_ep_io*)&response);
  } else {
    rv = usb_fuzzer_ep0_read(fd, (struct usb_fuzzer_ep_io*)&response);
  }
  if (rv < 0) {
    return rv;
  }
  sleep_ms(200);
  return 0;
}

#define FS_IOC_SETFLAGS _IOW('f', 2, long)
static void remove_dir(const char* dir)
{
  DIR* dp;
  struct dirent* ep;
  int iter = 0;
retry:
  while (umount2(dir, MNT_DETACH) == 0) {
  }
  dp = opendir(dir);
  if (dp == NULL) {
    if (errno == EMFILE) {
      exit(1);
    }
    exit(1);
  }
  while ((ep = readdir(dp))) {
    if (strcmp(ep->d_name, ".") == 0 || strcmp(ep->d_name, "..") == 0)
      continue;
    char filename[FILENAME_MAX];
    snprintf(filename, sizeof(filename), "%s/%s", dir, ep->d_name);
    while (umount2(filename, MNT_DETACH) == 0) {
    }
    struct stat st;
    if (lstat(filename, &st))
      exit(1);
    if (S_ISDIR(st.st_mode)) {
      remove_dir(filename);
      continue;
    }
    int i;
    for (i = 0;; i++) {
      if (unlink(filename) == 0)
        break;
      if (errno == EPERM) {
        int fd = open(filename, O_RDONLY);
        if (fd != -1) {
          long flags = 0;
          if (ioctl(fd, FS_IOC_SETFLAGS, &flags) == 0)
            close(fd);
          continue;
        }
      }
      if (errno == EROFS) {
        break;
      }
      if (errno != EBUSY || i > 100)
        exit(1);
      if (umount2(filename, MNT_DETACH))
        exit(1);
    }
  }
  closedir(dp);
  int i;
  for (i = 0;; i++) {
    if (rmdir(dir) == 0)
      break;
    if (i < 100) {
      if (errno == EPERM) {
        int fd = open(dir, O_RDONLY);
        if (fd != -1) {
          long flags = 0;
          if (ioctl(fd, FS_IOC_SETFLAGS, &flags) == 0)
            close(fd);
          continue;
        }
      }
      if (errno == EROFS) {
        break;
      }
      if (errno == EBUSY) {
        if (umount2(dir, MNT_DETACH))
          exit(1);
        continue;
      }
      if (errno == ENOTEMPTY) {
        if (iter < 100) {
          iter++;
          goto retry;
        }
      }
    }
    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");
}

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 < 5; 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 + (call == 0 ? 2000 : 0) +
                                     (call == 1 ? 300 : 0) +
                                     (call == 2 ? 300 : 0));
      break;
    }
  }
  for (i = 0; i < 100 && __atomic_load_n(&running, __ATOMIC_RELAXED); i++)
    sleep_ms(1);
  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++) {
    char cwdbuf[32];
    sprintf(cwdbuf, "./%d", iter);
    if (mkdir(cwdbuf, 0777))
      exit(1);
    int pid = fork();
    if (pid < 0)
      exit(1);
    if (pid == 0) {
      if (chdir(cwdbuf))
        exit(1);
      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;
    }
    remove_dir(cwdbuf);
  }
}

uint64_t r[1] = {0xffffffffffffffff};

void execute_call(int call)
{
  intptr_t res;
  switch (call) {
  case 0:
    *(uint8_t*)0x20000080 = 0x12;
    *(uint8_t*)0x20000081 = 1;
    *(uint16_t*)0x20000082 = 0;
    *(uint8_t*)0x20000084 = 0x91;
    *(uint8_t*)0x20000085 = 0x14;
    *(uint8_t*)0x20000086 = 0x8f;
    *(uint8_t*)0x20000087 = 0x40;
    *(uint16_t*)0x20000088 = 0x411;
    *(uint16_t*)0x2000008a = 0x12;
    *(uint16_t*)0x2000008c = 0x565f;
    *(uint8_t*)0x2000008e = 0;
    *(uint8_t*)0x2000008f = 0;
    *(uint8_t*)0x20000090 = 0;
    *(uint8_t*)0x20000091 = 1;
    *(uint8_t*)0x20000092 = 9;
    *(uint8_t*)0x20000093 = 2;
    *(uint16_t*)0x20000094 = 0x12;
    *(uint8_t*)0x20000096 = 1;
    *(uint8_t*)0x20000097 = 0;
    *(uint8_t*)0x20000098 = 0;
    *(uint8_t*)0x20000099 = 0;
    *(uint8_t*)0x2000009a = 0;
    *(uint8_t*)0x2000009b = 9;
    *(uint8_t*)0x2000009c = 4;
    *(uint8_t*)0x2000009d = 0xce;
    *(uint8_t*)0x2000009e = 0;
    *(uint8_t*)0x2000009f = 0;
    *(uint8_t*)0x200000a0 = 0x54;
    *(uint8_t*)0x200000a1 = 0x74;
    *(uint8_t*)0x200000a2 = 0x24;
    *(uint8_t*)0x200000a3 = 0;
    res = syz_usb_connect(0, 0x24, 0x20000080, 0);
    if (res != -1)
      r[0] = res;
    break;
  case 1:
    syz_usb_control_io(r[0], 0, 0);
    break;
  case 2:
    *(uint32_t*)0x200023c0 = 0xac;
    *(uint64_t*)0x200023c4 = 0x20000180;
    memcpy((void*)0x20000180, "\x00\x00\x11", 3);
    *(uint64_t*)0x200023cc = 0;
    *(uint64_t*)0x200023d4 = 0;
    *(uint64_t*)0x200023dc = 0;
    *(uint64_t*)0x200023e4 = 0;
    *(uint64_t*)0x200023ec = 0;
    *(uint64_t*)0x200023f4 = 0;
    *(uint64_t*)0x200023fc = 0;
    *(uint64_t*)0x20002404 = 0;
    *(uint64_t*)0x2000240c = 0;
    *(uint64_t*)0x20002414 = 0;
    *(uint64_t*)0x2000241c = 0;
    *(uint64_t*)0x20002424 = 0;
    *(uint64_t*)0x2000242c = 0;
    *(uint64_t*)0x20002434 = 0;
    *(uint64_t*)0x2000243c = 0;
    *(uint64_t*)0x20002444 = 0;
    *(uint64_t*)0x2000244c = 0;
    *(uint64_t*)0x20002454 = 0;
    *(uint64_t*)0x2000245c = 0;
    *(uint64_t*)0x20002464 = 0;
    syz_usb_control_io(r[0], 0, 0x200023c0);
    break;
  case 3:
    memcpy((void*)0x20000000, "/dev/dlm_plock\000", 15);
    syscall(__NR_openat, 0xffffffffffffff9c, 0x20000000, 0xc3847a92a315b5c9, 0);
    break;
  case 4:
    *(uint16_t*)0x20961fe4 = 2;
    *(uint16_t*)0x20961fe6 = htobe16(0);
    *(uint8_t*)0x20961fe8 = 0xac;
    *(uint8_t*)0x20961fe9 = 0x14;
    *(uint8_t*)0x20961fea = 0x14;
    *(uint8_t*)0x20961feb = 0;
    syscall(__NR_setsockopt, -1, 0x84, 0x6e, 0x20961fe4, 0x10);
    break;
  }
}
int main(void)
{
  syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0);
  for (procid = 0; procid < 6; procid++) {
    if (fork() == 0) {
      use_temporary_dir();
      loop();
    }
  }
  sleep(1000000);
  return 0;
}