// https://syzkaller.appspot.com/bug?id=5b6be32aa55adc05444701e80c3b1eae5d9079d2
// autogenerated by syzkaller (https://github.com/google/syzkaller)

#define _GNU_SOURCE

#include <dirent.h>
#include <endian.h>
#include <errno.h>
#include <fcntl.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/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/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 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_MAX_EP_NUM 32

struct usb_device_index {
  struct usb_device_descriptor* dev;
  struct usb_config_descriptor* config;
  unsigned config_length;
  struct usb_interface_descriptor* iface;
  struct usb_endpoint_descriptor* eps[USB_MAX_EP_NUM];
  unsigned eps_num;
};

static bool parse_usb_descriptor(char* buffer, size_t length,
                                 struct usb_device_index* index)
{
  if (length <
      sizeof(*index->dev) + sizeof(*index->config) + sizeof(*index->iface))
    return false;
  index->dev = (struct usb_device_descriptor*)buffer;
  index->config = (struct usb_config_descriptor*)(buffer + sizeof(*index->dev));
  index->config_length = length - sizeof(*index->dev);
  index->iface =
      (struct usb_interface_descriptor*)(buffer + sizeof(*index->dev) +
                                         sizeof(*index->config));
  index->eps_num = 0;
  size_t offset = 0;
  while (true) {
    if (offset == length)
      break;
    if (offset + 1 < length)
      break;
    uint8_t length = buffer[offset];
    uint8_t type = buffer[offset + 1];
    if (type == USB_DT_ENDPOINT) {
      index->eps[index->eps_num] =
          (struct usb_endpoint_descriptor*)(buffer + offset);
      index->eps_num++;
    }
    if (index->eps_num == USB_MAX_EP_NUM)
      break;
    offset += 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_EP0_READ _IOWR('U', 2, struct usb_fuzzer_event)
#define USB_FUZZER_IOCTL_EP0_WRITE _IOW('U', 3, struct usb_fuzzer_ep_io)
#define USB_FUZZER_IOCTL_EP_ENABLE _IOW('U', 4, struct usb_endpoint_descriptor)
#define USB_FUZZER_IOCTL_EP_WRITE _IOW('U', 6, struct usb_fuzzer_ep_io)
#define USB_FUZZER_IOCTL_CONFIGURE _IO('U', 8)
#define USB_FUZZER_IOCTL_VBUS_DRAW _IOW('U', 9, 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_ep0_read(int fd, struct usb_fuzzer_event* event)
{
  return ioctl(fd, USB_FUZZER_IOCTL_EP0_READ, 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_ep_write(int fd, struct usb_fuzzer_ep_io* io)
{
  return ioctl(fd, USB_FUZZER_IOCTL_EP_WRITE, 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;
};

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 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, bool* done)
{
  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 (str_idx >= descs->strs_len)
          return false;
        *response_data = descs->strs[str_idx].str;
        *response_length = descs->strs[str_idx].len;
        return true;
      case USB_DT_BOS:
        *response_data = descs->bos;
        *response_length = descs->bos_len;
        return true;
      case USB_DT_DEVICE_QUALIFIER:
        *response_data = descs->qual;
        *response_length = descs->qual_len;
        return true;
      default:
        exit(1);
        return false;
      }
      break;
    case USB_REQ_SET_CONFIGURATION:
      *response_length = 0;
      *response_data = NULL;
      *done = true;
      return true;
    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)
{
  int64_t speed = a0;
  int64_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 = false;
  rv = parse_usb_descriptor(dev, dev_len, &index);
  if (!rv)
    return -1;
  int fd = usb_fuzzer_open();
  if (fd < 0)
    return -1;
  char device[32];
  sprintf(&device[0], "dummy_udc.%llu", procid);
  rv = usb_fuzzer_init(fd, speed, "dummy_udc", &device[0]);
  if (rv < 0)
    return -1;
  rv = usb_fuzzer_run(fd);
  if (rv < 0)
    return -1;
  bool done = false;
  while (!done) {
    struct usb_fuzzer_control_event event;
    event.inner.type = 0;
    event.inner.length = sizeof(event.ctrl);
    rv = usb_fuzzer_ep0_read(fd, (struct usb_fuzzer_event*)&event);
    if (rv < 0)
      return -1;
    if (event.inner.type != USB_FUZZER_EVENT_CONTROL)
      continue;
    bool response_found = false;
    char* response_data = NULL;
    uint32_t response_length = 0;
    response_found = lookup_connect_response(
        descs, &index, &event.ctrl, &response_data, &response_length, &done);
    if (!response_found)
      return -1;
    if (done) {
      int rv = usb_fuzzer_vbus_draw(fd, index.config->bMaxPower);
      if (rv < 0)
        return -1;
      rv = usb_fuzzer_configure(fd);
      if (rv < 0)
        return -1;
      unsigned ep;
      for (ep = 0; ep < index.eps_num; ep++) {
        rv = usb_fuzzer_ep_enable(fd, index.eps[ep]);
        if (rv < 0)
          exit(1);
      }
    }
    struct usb_fuzzer_ep_io_data response;
    response.inner.ep = 0;
    response.inner.flags = 0;
    if (response_length > sizeof(response.data))
      response_length = 0;
    response.inner.length = response_length;
    if (response_data)
      memcpy(&response.data[0], response_data, response_length);
    if (event.ctrl.wLength < response.inner.length)
      response.inner.length = event.ctrl.wLength;
    usb_fuzzer_ep0_write(fd, (struct usb_fuzzer_ep_io*)&response);
  }
  sleep_ms(200);
  return fd;
}

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 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;
    }
  }
}

void execute_one(void)
{
  *(uint8_t*)0x200000c0 = 0x12;
  *(uint8_t*)0x200000c1 = 1;
  *(uint16_t*)0x200000c2 = 0;
  *(uint8_t*)0x200000c4 = 0xb1;
  *(uint8_t*)0x200000c5 = 0x7c;
  *(uint8_t*)0x200000c6 = 0x95;
  *(uint8_t*)0x200000c7 = 8;
  *(uint16_t*)0x200000c8 = 0x6a2;
  *(uint16_t*)0x200000ca = 0x6810;
  *(uint16_t*)0x200000cc = 0x1baf;
  *(uint8_t*)0x200000ce = 0;
  *(uint8_t*)0x200000cf = 0;
  *(uint8_t*)0x200000d0 = 0;
  *(uint8_t*)0x200000d1 = 1;
  *(uint8_t*)0x200000d2 = 9;
  *(uint8_t*)0x200000d3 = 2;
  *(uint16_t*)0x200000d4 = 0x2f;
  *(uint8_t*)0x200000d6 = 1;
  *(uint8_t*)0x200000d7 = 4;
  *(uint8_t*)0x200000d8 = 0;
  *(uint8_t*)0x200000d9 = 0;
  *(uint8_t*)0x200000da = 9;
  *(uint8_t*)0x200000db = 9;
  *(uint8_t*)0x200000dc = 4;
  *(uint8_t*)0x200000dd = 0xb0;
  *(uint8_t*)0x200000de = 0;
  *(uint8_t*)0x200000df = 3;
  *(uint8_t*)0x200000e0 = 0xdd;
  *(uint8_t*)0x200000e1 = 0x8c;
  *(uint8_t*)0x200000e2 = 0x55;
  *(uint8_t*)0x200000e3 = 8;
  *(uint8_t*)0x200000e4 = 7;
  *(uint8_t*)0x200000e5 = 5;
  *(uint8_t*)0x200000e6 = 6;
  *(uint8_t*)0x200000e7 = 4;
  *(uint16_t*)0x200000e8 = 0x7e;
  *(uint8_t*)0x200000ea = 6;
  *(uint8_t*)0x200000eb = 4;
  *(uint8_t*)0x200000ec = 3;
  *(uint8_t*)0x200000ed = 2;
  *(uint8_t*)0x200000ee = 0x22;
  *(uint8_t*)0x200000ef = 7;
  *(uint8_t*)0x200000f0 = 5;
  *(uint8_t*)0x200000f1 = -1;
  *(uint8_t*)0x200000f2 = 0;
  *(uint16_t*)0x200000f3 = 0;
  *(uint8_t*)0x200000f5 = 2;
  *(uint8_t*)0x200000f6 = 0xc3;
  *(uint8_t*)0x200000f7 = 0xe1;
  *(uint8_t*)0x200000f8 = 7;
  *(uint8_t*)0x200000f9 = 5;
  *(uint8_t*)0x200000fa = 8;
  *(uint8_t*)0x200000fb = 0;
  *(uint16_t*)0x200000fc = 0;
  *(uint8_t*)0x200000fe = 0;
  *(uint8_t*)0x200000ff = 0;
  *(uint8_t*)0x20000100 = 0;
  syz_usb_connect(0, 0x41, 0x200000c0, 0);
}
int main(void)
{
  syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0);
  loop();
  return 0;
}