// https://syzkaller.appspot.com/bug?id=fd5dc09bea648f957d40969ebb66656f109101f5
// 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 MAX_FDS 30

#define USB_MAX_IFACE_NUM 4
#define USB_MAX_EP_NUM 32

struct usb_iface_index {
  struct usb_interface_descriptor* iface;
  uint8_t bInterfaceNumber;
  uint8_t bAlternateSetting;
  uint8_t bInterfaceClass;
  struct usb_endpoint_descriptor eps[USB_MAX_EP_NUM];
  int eps_num;
};

struct usb_device_index {
  struct usb_device_descriptor* dev;
  struct usb_config_descriptor* config;
  uint8_t bDeviceClass;
  uint8_t bMaxPower;
  int config_length;
  struct usb_iface_index ifaces[USB_MAX_IFACE_NUM];
  int ifaces_num;
  int iface_cur;
};

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->bDeviceClass = index->dev->bDeviceClass;
  index->bMaxPower = index->config->bMaxPower;
  index->config_length = length - sizeof(*index->dev);
  index->iface_cur = -1;
  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;
      index->ifaces[index->ifaces_num].bInterfaceNumber =
          iface->bInterfaceNumber;
      index->ifaces[index->ifaces_num].bAlternateSetting =
          iface->bAlternateSetting;
      index->ifaces[index->ifaces_num].bInterfaceClass = iface->bInterfaceClass;
      index->ifaces_num++;
    }
    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) {
        memcpy(&iface->eps[iface->eps_num], buffer + offset,
               sizeof(iface->eps[iface->eps_num]));
        iface->eps_num++;
      }
    }
    offset += desc_length;
  }
  return true;
}

#define UDC_NAME_LENGTH_MAX 128

struct usb_raw_init {
  __u8 driver_name[UDC_NAME_LENGTH_MAX];
  __u8 device_name[UDC_NAME_LENGTH_MAX];
  __u8 speed;
};

enum usb_raw_event_type {
  USB_RAW_EVENT_INVALID = 0,
  USB_RAW_EVENT_CONNECT = 1,
  USB_RAW_EVENT_CONTROL = 2,
};

struct usb_raw_event {
  __u32 type;
  __u32 length;
  __u8 data[0];
};

struct usb_raw_ep_io {
  __u16 ep;
  __u16 flags;
  __u32 length;
  __u8 data[0];
};

#define USB_RAW_IOCTL_INIT _IOW('U', 0, struct usb_raw_init)
#define USB_RAW_IOCTL_RUN _IO('U', 1)
#define USB_RAW_IOCTL_EVENT_FETCH _IOR('U', 2, struct usb_raw_event)
#define USB_RAW_IOCTL_EP0_WRITE _IOW('U', 3, struct usb_raw_ep_io)
#define USB_RAW_IOCTL_EP0_READ _IOWR('U', 4, struct usb_raw_ep_io)
#define USB_RAW_IOCTL_EP_ENABLE _IOW('U', 5, struct usb_endpoint_descriptor)
#define USB_RAW_IOCTL_EP_DISABLE _IOW('U', 6, __u32)
#define USB_RAW_IOCTL_EP_WRITE _IOW('U', 7, struct usb_raw_ep_io)
#define USB_RAW_IOCTL_EP_READ _IOWR('U', 8, struct usb_raw_ep_io)
#define USB_RAW_IOCTL_CONFIGURE _IO('U', 9)
#define USB_RAW_IOCTL_VBUS_DRAW _IOW('U', 10, __u32)

static int usb_raw_open()
{
  return open("/dev/raw-gadget", O_RDWR);
}

static int usb_raw_init(int fd, uint32_t speed, const char* driver,
                        const char* device)
{
  struct usb_raw_init arg;
  strncpy((char*)&arg.driver_name[0], driver, sizeof(arg.driver_name));
  strncpy((char*)&arg.device_name[0], device, sizeof(arg.device_name));
  arg.speed = speed;
  return ioctl(fd, USB_RAW_IOCTL_INIT, &arg);
}

static int usb_raw_run(int fd)
{
  return ioctl(fd, USB_RAW_IOCTL_RUN, 0);
}

static int usb_raw_event_fetch(int fd, struct usb_raw_event* event)
{
  return ioctl(fd, USB_RAW_IOCTL_EVENT_FETCH, event);
}

static int usb_raw_ep0_write(int fd, struct usb_raw_ep_io* io)
{
  return ioctl(fd, USB_RAW_IOCTL_EP0_WRITE, io);
}

static int usb_raw_ep0_read(int fd, struct usb_raw_ep_io* io)
{
  return ioctl(fd, USB_RAW_IOCTL_EP0_READ, io);
}

static int usb_raw_ep_enable(int fd, struct usb_endpoint_descriptor* desc)
{
  return ioctl(fd, USB_RAW_IOCTL_EP_ENABLE, desc);
}

static int usb_raw_ep_disable(int fd, int ep)
{
  return ioctl(fd, USB_RAW_IOCTL_EP_DISABLE, ep);
}

static int usb_raw_configure(int fd)
{
  return ioctl(fd, USB_RAW_IOCTL_CONFIGURE, 0);
}

static int usb_raw_vbus_draw(int fd, uint32_t power)
{
  return ioctl(fd, USB_RAW_IOCTL_VBUS_DRAW, power);
}

#define MAX_USB_FDS 6

struct usb_info {
  int fd;
  struct usb_device_index index;
};

static struct usb_info usb_devices[MAX_USB_FDS];
static int usb_devices_num;

static struct usb_device_index* add_usb_index(int fd, char* dev, size_t dev_len)
{
  int i = __atomic_fetch_add(&usb_devices_num, 1, __ATOMIC_RELAXED);
  if (i >= MAX_USB_FDS)
    return NULL;
  int rv = 0;
  rv = parse_usb_descriptor(dev, dev_len, &usb_devices[i].index);
  if (!rv)
    return NULL;
  __atomic_store_n(&usb_devices[i].fd, fd, __ATOMIC_RELEASE);
  return &usb_devices[i].index;
}

static struct usb_device_index* lookup_usb_index(int fd)
{
  int i;
  for (i = 0; i < MAX_USB_FDS; i++) {
    if (__atomic_load_n(&usb_devices[i].fd, __ATOMIC_ACQUIRE) == fd) {
      return &usb_devices[i].index;
    }
  }
  return NULL;
}

static void set_interface(int fd, int n)
{
  struct usb_device_index* index = lookup_usb_index(fd);
  int ep;
  if (!index)
    return;
  if (index->iface_cur >= 0 && index->iface_cur < index->ifaces_num) {
    for (ep = 0; ep < index->ifaces[index->iface_cur].eps_num; ep++) {
      int rv = usb_raw_ep_disable(fd, ep);
      if (rv < 0) {
      } else {
      }
    }
  }
  if (n >= 0 && n < index->ifaces_num) {
    for (ep = 0; ep < index->ifaces[n].eps_num; ep++) {
      int rv = usb_raw_ep_enable(fd, &index->ifaces[n].eps[ep]);
      if (rv < 0) {
      } else {
      }
    }
    index->iface_cur = n;
  }
}

static int configure_device(int fd)
{
  struct usb_device_index* index = lookup_usb_index(fd);
  if (!index)
    return -1;
  int rv = usb_raw_vbus_draw(fd, index->bMaxPower);
  if (rv < 0) {
    return rv;
  }
  rv = usb_raw_configure(fd);
  if (rv < 0) {
    return rv;
  }
  set_interface(fd, 0);
  return 0;
}

#define USB_MAX_PACKET_SIZE 1024

struct usb_raw_control_event {
  struct usb_raw_event inner;
  struct usb_ctrlrequest ctrl;
  char data[USB_MAX_PACKET_SIZE];
};

struct usb_raw_ep_io_data {
  struct usb_raw_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(int fd,
                                    struct vusb_connect_descriptors* descs,
                                    struct usb_ctrlrequest* ctrl,
                                    char** response_data,
                                    uint32_t* response_length)
{
  struct usb_device_index* index = lookup_usb_index(fd);
  uint8_t str_idx;
  if (!index)
    return false;
  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;
  }
  int fd = usb_raw_open();
  if (fd < 0) {
    return fd;
  }
  if (fd >= MAX_FDS) {
    close(fd);
    return -1;
  }
  struct usb_device_index* index = add_usb_index(fd, dev, dev_len);
  if (!index) {
    return -1;
  }
  char device[32];
  sprintf(&device[0], "dummy_udc.%llu", procid);
  int rv = usb_raw_init(fd, speed, "dummy_udc", &device[0]);
  if (rv < 0) {
    return rv;
  }
  rv = usb_raw_run(fd);
  if (rv < 0) {
    return rv;
  }
  bool done = false;
  while (!done) {
    struct usb_raw_control_event event;
    event.inner.type = 0;
    event.inner.length = sizeof(event.ctrl);
    rv = usb_raw_event_fetch(fd, (struct usb_raw_event*)&event);
    if (rv < 0) {
      return rv;
    }
    if (event.inner.type != USB_RAW_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(
          fd, descs, &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 = configure_device(fd);
      if (rv < 0) {
        return rv;
      }
    }
    struct usb_raw_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_raw_ep0_write(fd, (struct usb_raw_ep_io*)&response);
    } else {
      rv = usb_raw_ep0_read(fd, (struct usb_raw_ep_io*)&response);
    }
    if (rv < 0) {
      return rv;
    }
  }
  sleep_ms(200);
  return fd;
}

int main(void)
{
  syscall(__NR_mmap, 0x20000000ul, 0x1000000ul, 3ul, 0x32ul, -1, 0);

  memcpy((void*)0x200002c0,
         "\x12\x01\x00\x00\xd3\x92\x62\x08\x7f\x18\x00\x02\x31\x1f\x00\x00\x00"
         "\x01\x09\x02\x24\x00\x01\x00\x00\x00\x00\x09\x04\x00\x00\x02\x4b\x92"
         "\x16\x00\x09\x05\x0b\x00\x00\x00\x00\x00\x00\x09\x05\x8a\xa7\x3b\xcc"
         "\xdd\xbe\x80\xb9\x8b\x82\xc2\xe0\x5a\x55\x78\xf4\x36\xae\xb8\xca\x36"
         "\x36\xff\x3a\x58\xb1\x83\xb5\xb2\x21\x80\x82\x06\x32\x76\x81\xaf\xc0"
         "\x99\x09\xe7\x06\x51\x2e\x16\x29\xcc\x69\x67\xba\x5b\x49\x54\x76\xec"
         "\x8e\x89\x95\x69\x51\x88\xf5\x34\x4b\x22\x21\xd5\x02\xb5\xf8\xda\x27"
         "\x56\xd7\x1b\xea\xcc\xf1\x04\x37\x07\xf5\x61\xb9\x51\x1f\xe0\x69\xf8"
         "\xf3\x0d\x81\x7b\x49\xaa\xb6\xdd\x22\x43\xfc\xca\xcc\xf1\x07\x50\x6f"
         "\xd9\x78\xb7\x5f\x03\xce\xcd\x96\x3e\xb7\x63\xc4\x8e\x6e\xf9\xa1\x05"
         "\x07\xd6\xdf\x42\x04\xff\xd7\x78\x3b\xda\x26\x0e\x00\x00\x00\x00\x00"
         "\x00\xed\xcc\xc3\xcf\x62\x5e\x15\xb5\xa8\x5d\x23\xa0\x22\xd4\x9f\x04"
         "\xcc\x78\x01\x06\xea\x2e\x2e\x2b\x3d\xf7\x13\xf9\x96\x1d\x1c\xac\xde"
         "\xd9\x06\x60\xa6\xe4\x0e\x99\x3b\x6c\x06\xa3\x10\x86\x4c\x9a\x68\x80"
         "\x70\x1a\xd7\x5c\xc2\xf0\xea\x88\xe3\x3b\x34\x24\xf5\xf1\xb9\xb4\x95"
         "\xe1\xa2\xe5\xb1\x86\x4e\xd2\x94\x85\x37\x0a\xcd\x3f\x4a\xd8\xf9\x89"
         "\x01\x63\xb9\xd9\xd6\x9e\x2c\xc0\x00\x72\xee\x33\x24\x11\xdd\x51\x86"
         "\x34\x39\x68\xbd\x42\xa1\x4a\x75\x4f\x1e\xe1\x1c\xc0\x52\x16\x32\x53"
         "\x33\x3c\x21\xa3\x4d\x9a\x28\x80\x5e\x7a\x9a\xb6\xa5\x0c\xf1\x82\x6d"
         "\xcf\xb5\xee\xa9\x8d\x35\x00\x00",
         331);
  syz_usb_connect(0, 0x36, 0x200002c0, 0);
  return 0;
}