// https://syzkaller.appspot.com/bug?id=323cf33afff0156e5c926803d69cb7d06e450645
// autogenerated by syzkaller (https://github.com/google/syzkaller)

#define _GNU_SOURCE

#include <endian.h>
#include <errno.h>
#include <fcntl.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/stat.h>
#include <sys/syscall.h>
#include <sys/types.h>
#include <unistd.h>

#include <linux/usb/ch9.h>

unsigned long long procid;

static void sleep_ms(uint64_t ms)
{
  usleep(ms * 1000);
}

#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;
}

int main(void)
{
  syscall(__NR_mmap, 0x20000000, 0x1000000, 3, 0x32, -1, 0);

  memcpy(
      (void*)0x20000380,
      "\x12\x01\x00\x00\xad\x08\x75\x10\x73\x05\x21\x4d\x91\x00\x00\x00\x00\x01"
      "\x09\x02\x24\x00\x01\x00\x00\x00\x00\x09\x04\xc4\xc5\x02\xe1\xa7\xdf\x00"
      "\x09\x05\x01\x03\x08\x00\x00\x00\x00\x09\x05\x83\x11\x00\x00\x00\x00\x00"
      "\x4d\xfa\xce\x07\x2f\x4b\x36\xbd\xef\x11\x85\xf2\x50\x32\x0c\xc9\x20\xcd"
      "\xec\x18\x46\x1c\xb2\x43\xb9\xe8\x2a\xa1\x11\x04\x33\x75\xce\x70\x52\x30"
      "\xc0\x8e\x40\x32\x44\x5d\x92\x04\x72\x7c\xac\x2d\x2c\x9a\xa6\x72\xa4\xc5"
      "\xc4\x99\xe6\xbf\xd1\x75\x8e\x79\xdc\xe8\xb5\x3a\x25\x55\xed\xc1\xf8\x41"
      "\xb6\xa8\xe3\xe1\xed\xcb\x40\x75\xc7\x5c\x3f\x1b\x15\x3c\x2a\x36\x05\x05"
      "\x56\xfe\xf4\x54\x3d\xe7\xc3\xaf\xff\x18\x47\xd7\x1a\xe3\xa9\x4c\xcc\x09"
      "\x78\x37\x32\x5f\x52\xea\xc6\xd3\x5e\xe3\x7b\x82\xb1\x9f\x05\x61\x76\x06"
      "\x90\xff\xc3\x85\x11\xf7\x9e\xec\x0b\x1b\xf5\x1c\xcd\x1f\x8f\xe2\x6b\x05"
      "\xc4\xef\x24\x24\x31\x13\x20\x28\xb3\x5b\xd4\x6b\x57\x32\x21\x49\xd2\x2f"
      "\xce\x8a\x2b\xac\xb3\xfd\xbf\x6d\x11\x27\xd9\xae\xd0\xac\x3f\x93\x54\x35"
      "\x42\x5e\x82\x47\xca\x59\x36\x07\x3a\x4a\x0e\x48\xf1\xfe\x23\xde\xd3\xcc"
      "\x10\x17\x7d\x58\x52\x11\xdf\xfa\x83\x4e\xa7\xf5\xe2\x58\x70\xdc\xf1\xdf"
      "\xfa\x90\xa9\x1f\xc7\x1b\x2d\x0a\x26\x80\x68\x00\xcd\x6f\x92\x00\x6c\x3b"
      "\x6e\xda\x67\xf7\x74\x3d\xb6\xee\xde\xd0\xba\x35\x55\x56\xc2\x4c\x83\x18"
      "\x07\x4b\x79\xc1\xc2\x02\xae\x55\xa5\x42\x4f\xd3\xf7\x9a\x01\x40\xb3\xba"
      "\xea\x77\x2e\xcf\xce\x60\x4b\xa8\xd6\x4c\xe3\xe2\x20\xa0\x66\x4f\x26\x48"
      "\x31\xfa\x6d\x53\x15\xe2\xed\x8e\x52\x9e\xac\xd5\x79\x80\xad\xcb\x9e\x37"
      "\x7a\x0d\xff\xcb\xa9\x91\x42\x77\xe5\xcc\x9e\xce\x73\xef\x47\xb0\x4a\x53"
      "\xaf\x2a\xb5\x22\x39\xb4\x7e\xf1\x2a\x4e\x95\x4a\xb9\xe3\xcf\xf0\x24\xc8"
      "\xf3\x21\xbf\xe5\xac\xbb\x47\x28\x9c\xe2\x79\x5a\xb5\x1f\x31\xbb\xb0\x94"
      "\xc0\x6a\xc0\xf9\xf2\x9a\x6f\x71\x62\xef\x48\x57\x7d\xea\x10\x43\xdd\x81"
      "\xe7\xf4\x86\x9b\x5a\xc0\x02\x32\xa7\x56\x60\x2d\x3f\x43\x1d\xf7\xf0\x99"
      "\xb6\x42\xa0\x4d\x01\x00\x00\x00\x84\x00\xe3\xfd\xd1\x2c\x8d\x57\x9d\xfe"
      "\xdf\xb0\x06\x92\x65\xa3\x0c\x5e\x75\x3c\x03\xcf\x30\xe8\x22\xd0\xe0\x52"
      "\x27\xe0\xd3\xc9\xcd\x6a\x7d\x53\x8b\x77\xf9\x0b\x48\x90\x64\x1d\x5a\x82"
      "\x8e\xcb\xbf\x71\x84\xd4\x19\xaa\x2b\x15\x4e\xcc\x7d\x6e\x4c\xf8\xaf\x0b"
      "\x6f\x26\x48\x38\x0b\x8b\x80\x19\x19\x53\xea\x7d\x5e\x28\x3a\xe3\xea\xb0"
      "\xed\x2a\x68\x3b\xda\x4e\x78\x9d\x00\x00\x00\x00\x00\x00\x00\x00\x00\x00"
      "\x00\x00\x00\x00\x00",
      563);
  syz_usb_connect(0, 0x36, 0x20000380, 0);
  return 0;
}