[Linux Kernel Bug] general protection fault in try_to_register_card

[Jiaming Zhang]

Dear Linux kernel developers and maintainers:

We are writing to report a general protection fault discovered in the
kernel with our modified syzkaller. This bug is reproducible on the
latest version (commit 67029a49db6c1f21106a1b5fcdd0ea234a6e0711).

The kernel console output, kernel config, syzkaller reproducer, and C
reproducer are attached to this email to help analysis. The KASAN
report from kernel (commit 67029a49), formatted by syz-symbolize, is
listed below:

==================================================================
e1000: eth0 NIC Link is Up 1000 Mbps Full Duplex, Flow Control: RX
usb 1-1: new full-speed USB device number 2 using dummy_hcd
usb 1-1: not running at top speed; connect to a high speed hub
usb 1-1: config 2 has an invalid interface number: 131 but max is 3
usb 1-1: config 2 has an invalid interface number: 160 but max is 3
usb 1-1: config 2 has an invalid descriptor of length 0, skipping
remainder of the config
usb 1-1: config 2 has 2 interfaces, different from the descriptor's value: 4
usb 1-1: config 2 has no interface number 0
usb 1-1: config 2 has no interface number 1
usb 1-1: config 2 interface 160 altsetting 9 has an invalid descriptor
for endpoint zero, skipping
usb 1-1: config 2 interface 160 altsetting 9 has 2 endpoint
descriptors, different from the interface descriptor's value: 16
usb 1-1: config 2 interface 131 has no altsetting 0
usb 1-1: config 2 interface 160 has no altsetting 0
usb 1-1: New USB device found, idVendor=0dba, idProduct=5000, bcdDevice=3a.c9
usb 1-1: New USB device strings: Mfr=1, Product=2, SerialNumber=3
usb 1-1: Product: syz
usb 1-1: Manufacturer: syz
usb 1-1: SerialNumber: syz
usb 1-1: MBOX3: Initialized.
Oops: general protection fault, probably for non-canonical address
0xdffffc000000001c: 0000 [#1] SMP KASAN NOPTI
KASAN: null-ptr-deref in range [0x00000000000000e0-0x00000000000000e7]
CPU: 1 UID: 0 PID: 793 Comm: kworker/1:2 Not tainted
6.17.0-12904-g67029a49db6c #1 PREEMPT(full)
Hardware name: QEMU Standard PC (i440FX + PIIX, 1996), BIOS 1.15.0-1 04/01/2014
Workqueue: usb_hub_wq hub_event
RIP: 0010:usb_interface_claimed include/linux/usb.h:918 [inline]
RIP: 0010:try_to_register_card+0x248/0x300 sound/usb/card.c:896
Code: de cd 30 f9 49 8b 3f 44 89 f6 e8 43 e5 fa fd 49 89 c6 49 81 c6
e0 00 00 00 4c 89 f0 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c
08 00 74 08 4c 89 f7 e8 aa cd 30 f9 49 83 3e 00 74 73 e8 ff
RSP: 0018:ffffc9000462eb80 EFLAGS: 00010202
RAX: 000000000000001c RBX: ffff888049b02a30 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000000000a0
RBP: ffffc9000462ec30 R08: ffffc9000462e9e7 R09: 1ffff920008c5d3c
R10: dffffc0000000000 R11: ffffffff88f59950 R12: 00000000000000f8
R13: 1ffff11009360559 R14: 00000000000000e0 R15: ffff888049b02a38
FS:  0000000000000000(0000) GS:ffff8880ec976000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f86fb0e16f8 CR3: 0000000028a6b000 CR4: 0000000000752ef0
PKRU: 55555554
Call Trace:
 <TASK>
 usb_audio_probe+0x143f/0x1e60 sound/usb/card.c:1039
 usb_probe_interface+0x668/0xc30 drivers/usb/core/driver.c:396
 really_probe+0x26d/0x9f0 drivers/base/dd.c:659
 __driver_probe_device+0x190/0x390 drivers/base/dd.c:801
 driver_probe_device+0x4f/0x430 drivers/base/dd.c:831
 __device_attach_driver+0x2ce/0x530 drivers/base/dd.c:959
 bus_for_each_drv+0x251/0x2e0 drivers/base/bus.c:462
 __device_attach+0x2b7/0x400 drivers/base/dd.c:1031
 bus_probe_device+0x185/0x260 drivers/base/bus.c:537
 device_add+0x7b6/0xb50 drivers/base/core.c:3689
 usb_set_configuration+0x1a5c/0x20b0 drivers/usb/core/message.c:2210
 usb_generic_driver_probe+0x8d/0x150 drivers/usb/core/generic.c:250
 usb_probe_device+0x1c4/0x390 drivers/usb/core/driver.c:291
 really_probe+0x26d/0x9f0 drivers/base/dd.c:659
 __driver_probe_device+0x190/0x390 drivers/base/dd.c:801
 driver_probe_device+0x4f/0x430 drivers/base/dd.c:831
 __device_attach_driver+0x2ce/0x530 drivers/base/dd.c:959
 bus_for_each_drv+0x251/0x2e0 drivers/base/bus.c:462
 __device_attach+0x2b7/0x400 drivers/base/dd.c:1031
 bus_probe_device+0x185/0x260 drivers/base/bus.c:537
 device_add+0x7b6/0xb50 drivers/base/core.c:3689
 usb_new_device+0xb9d/0x1a00 drivers/usb/core/hub.c:2694
 hub_port_connect drivers/usb/core/hub.c:5566 [inline]
 hub_port_connect_change drivers/usb/core/hub.c:5706 [inline]
 port_event drivers/usb/core/hub.c:5870 [inline]
 hub_event+0x290c/0x49a0 drivers/usb/core/hub.c:5952
 process_one_work kernel/workqueue.c:3263 [inline]
 process_scheduled_works+0xae1/0x17b0 kernel/workqueue.c:3346
 worker_thread+0x8a0/0xda0 kernel/workqueue.c:3427
 kthread+0x711/0x8a0 kernel/kthread.c:463
 ret_from_fork+0x4bc/0x870 arch/x86/kernel/process.c:158
 ret_from_fork_asm+0x1a/0x30 arch/x86/entry/entry_64.S:245
 </TASK>
Modules linked in:
---[ end trace 0000000000000000 ]---
RIP: 0010:usb_interface_claimed include/linux/usb.h:918 [inline]
RIP: 0010:try_to_register_card+0x248/0x300 sound/usb/card.c:896
Code: de cd 30 f9 49 8b 3f 44 89 f6 e8 43 e5 fa fd 49 89 c6 49 81 c6
e0 00 00 00 4c 89 f0 48 c1 e8 03 48 b9 00 00 00 00 00 fc ff df <80> 3c
08 00 74 08 4c 89 f7 e8 aa cd 30 f9 49 83 3e 00 74 73 e8 ff
RSP: 0018:ffffc9000462eb80 EFLAGS: 00010202
RAX: 000000000000001c RBX: ffff888049b02a30 RCX: dffffc0000000000
RDX: 0000000000000000 RSI: 0000000000000000 RDI: 00000000000000a0
RBP: ffffc9000462ec30 R08: ffffc9000462e9e7 R09: 1ffff920008c5d3c
R10: dffffc0000000000 R11: ffffffff88f59950 R12: 00000000000000f8
R13: 1ffff11009360559 R14: 00000000000000e0 R15: ffff888049b02a38
FS:  0000000000000000(0000) GS:ffff8880ec976000(0000) knlGS:0000000000000000
CS:  0010 DS: 0000 ES: 0000 CR0: 0000000080050033
CR2: 00007f067e010980 CR3: 0000000024315000 CR4: 0000000000752ef0
PKRU: 55555554
----------------
Code disassembly (best guess):
   0: de cd                fmulp  %st,%st(5)
   2: 30 f9                xor    %bh,%cl
   4: 49 8b 3f              mov    (%r15),%rdi
   7: 44 89 f6              mov    %r14d,%esi
   a: e8 43 e5 fa fd        call   0xfdfae552
   f: 49 89 c6              mov    %rax,%r14
  12: 49 81 c6 e0 00 00 00 add    $0xe0,%r14
  19: 4c 89 f0              mov    %r14,%rax
  1c: 48 c1 e8 03          shr    $0x3,%rax
  20: 48 b9 00 00 00 00 00 movabs $0xdffffc0000000000,%rcx
  27: fc ff df
* 2a: 80 3c 08 00          cmpb   $0x0,(%rax,%rcx,1) <-- trapping instruction
  2e: 74 08                je     0x38
  30: 4c 89 f7              mov    %r14,%rdi
  33: e8 aa cd 30 f9        call   0xf930cde2
  38: 49 83 3e 00          cmpq   $0x0,(%r14)
  3c: 74 73                je     0xb1
  3e: e8                    .byte 0xe8
  3f: ff                    .byte 0xff
==================================================================

Please let me know if any further information is required.

Best Regards,
Jiaming Zhang.
// 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>

static 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
#define USB_MAX_FDS 6

struct usb_endpoint_index {
  struct usb_endpoint_descriptor desc;
  int handle;
};

struct usb_iface_index {
  struct usb_interface_descriptor* iface;
  uint8_t bInterfaceNumber;
  uint8_t bAlternateSetting;
  uint8_t bInterfaceClass;
  struct usb_endpoint_index 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;
};

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

static struct usb_info usb_devices[USB_MAX_FDS];

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

static int usb_devices_num;

static bool parse_usb_descriptor(const 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].desc, buffer + offset,
               sizeof(iface->eps[iface->eps_num].desc));
        iface->eps_num++;
      }
    }
    offset += desc_length;
  }
  return true;
}

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

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_in(int fd, const struct vusb_connect_descriptors* descs,
                           const struct usb_ctrlrequest* ctrl,
                           struct usb_qualifier_descriptor* qual,
                           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) {
          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_data = (char*)qual;
          *response_length = sizeof(*qual);
          return true;
        }
        *response_data = descs->qual;
        *response_length = descs->qual_len;
        return true;
      default:
        break;
      }
      break;
    default:
      break;
    }
    break;
  default:
    break;
  }
  return false;
}

typedef bool (*lookup_connect_out_response_t)(
    int fd, const struct vusb_connect_descriptors* descs,
    const struct usb_ctrlrequest* ctrl, bool* done);

static bool lookup_connect_response_out_generic(
    int fd, const struct vusb_connect_descriptors* descs,
    const struct usb_ctrlrequest* ctrl, bool* done)
{
  switch (ctrl->bRequestType & USB_TYPE_MASK) {
  case USB_TYPE_STANDARD:
    switch (ctrl->bRequest) {
    case USB_REQ_SET_CONFIGURATION:
      *done = true;
      return true;
    default:
      break;
    }
    break;
  }
  return false;
}

#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_EPS_NUM_MAX 30
#define USB_RAW_EP_NAME_MAX 16
#define USB_RAW_EP_ADDR_ANY 0xff

struct usb_raw_ep_caps {
  __u32 type_control : 1;
  __u32 type_iso : 1;
  __u32 type_bulk : 1;
  __u32 type_int : 1;
  __u32 dir_in : 1;
  __u32 dir_out : 1;
};

struct usb_raw_ep_limits {
  __u16 maxpacket_limit;
  __u16 max_streams;
  __u32 reserved;
};

struct usb_raw_ep_info {
  __u8 name[USB_RAW_EP_NAME_MAX];
  __u32 addr;
  struct usb_raw_ep_caps caps;
  struct usb_raw_ep_limits limits;
};

struct usb_raw_eps_info {
  struct usb_raw_ep_info eps[USB_RAW_EPS_NUM_MAX];
};

#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)
#define USB_RAW_IOCTL_EPS_INFO _IOR('U', 11, struct usb_raw_eps_info)
#define USB_RAW_IOCTL_EP0_STALL _IO('U', 12)
#define USB_RAW_IOCTL_EP_SET_HALT _IOW('U', 13, __u32)
#define USB_RAW_IOCTL_EP_CLEAR_HALT _IOW('U', 14, __u32)
#define USB_RAW_IOCTL_EP_SET_WEDGE _IOW('U', 15, __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_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);
}

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

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_ep0_stall(int fd)
{
  return ioctl(fd, USB_RAW_IOCTL_EP0_STALL, 0);
}

#define USB_MAX_PACKET_SIZE 4096

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];
};

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

static volatile long
syz_usb_connect_impl(uint64_t speed, uint64_t dev_len, const char* dev,
                     const struct vusb_connect_descriptors* descs,
                     lookup_connect_out_response_t lookup_connect_response_out)
{
  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;
    char* response_data = NULL;
    uint32_t response_length = 0;
    struct usb_qualifier_descriptor qual;
    if (event.ctrl.bRequestType & USB_DIR_IN) {
      if (!lookup_connect_response_in(fd, descs, &event.ctrl, &qual,
                                      &response_data, &response_length)) {
        usb_raw_ep0_stall(fd);
        continue;
      }
    } else {
      if (!lookup_connect_response_out(fd, descs, &event.ctrl, &done)) {
        usb_raw_ep0_stall(fd);
        continue;
      }
      response_data = NULL;
      response_length = event.ctrl.wLength;
    }
    if ((event.ctrl.bRequestType & USB_TYPE_MASK) == USB_TYPE_STANDARD &&
        event.ctrl.bRequest == USB_REQ_SET_CONFIGURATION) {
      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;
}

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;
  const char* dev = (const char*)a2;
  const struct vusb_connect_descriptors* descs =
      (const struct vusb_connect_descriptors*)a3;
  return syz_usb_connect_impl(speed, dev_len, dev, descs,
                              &lookup_connect_response_out_generic);
}

int main(void)
{
  syscall(__NR_mmap, /*addr=*/0x1ffff000ul, /*len=*/0x1000ul, /*prot=*/0ul,
          /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/-1,
          /*offset=*/0ul);
  syscall(__NR_mmap, /*addr=*/0x20000000ul, /*len=*/0x1000000ul,
          /*prot=PROT_WRITE|PROT_READ|PROT_EXEC*/ 7ul,
          /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/-1,
          /*offset=*/0ul);
  syscall(__NR_mmap, /*addr=*/0x21000000ul, /*len=*/0x1000ul, /*prot=*/0ul,
          /*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul, /*fd=*/-1,
          /*offset=*/0ul);
  const char* reason;
  (void)reason;
  if (write(1, "executing program\n", sizeof("executing program\n") - 1)) {
  }
  memcpy(
      (void*)0x200017c0,
      "\x12\x01\x00\x02\x2f\xf5\x2f\x08\xba\x0d\x00\x50\xc9\x3a\x01\x02\x03\x01"
      "\x09\x02\x43\x0d\x04\x02\x00\x50\x0b\x09\x04\x83\x04\x02\x57\xc1\xe4\x9b"
      "\x09\x05\x0a\x00\x08\x00\x92\xba\x04\x09\x05\x0c\x00\x10\x00\x08\x02\x31"
      "\xbf\x0a\x37\x10\x23\xa0\xd0\xaf\x63\x7b\x85\x1f\x09\xf9\x77\xf8\x57\x4b"
      "\x84\x53\xc7\x58\x98\xe3\xc3\x39\xad\xe9\x09\xc3\xed\xeb\x80\x11\x2d\x57"
      "\xf6\x41\xb3\x9e\x97\x1e\xfa\x0a\x97\x87\xa9\x78\x8c\xd3\xde\xb1\xa1\x74"
      "\x1d\x46\xf1\xae\xcc\x17\xea\x05\x79\xd6\xb3\x7e\x6f\x19\x4c\x0d\xf3\x2f"
      "\x91\xb0\x6a\x69\xce\xab\x57\x1b\x9b\x3d\xee\x32\x51\xa6\xe3\x36\xad\x93"
      "\x1d\x28\xfb\x73\x32\x24\x2e\x8e\x37\x3e\x6c\x30\x80\x6c\x71\x8a\xa6\xe1"
      "\x62\x22\xb8\xb5\x72\x27\x68\xe5\xaa\x95\x2f\xf7\x5a\xef\x60\xbb\xfe\x9a"
      "\x06\x67\x44\x4f\x33\xc5\xc0\xab\xd1\xa3\xf3\xeb\x6c\xc8\x69\x8d\xdb\x8c"
      "\xb3\x18\xea\xb5\x33\xc1\x7d\x3f\x0c\xb0\xe9\x35\xd2\x21\x8a\xd5\x47\xde"
      "\x8c\xc6\xd4\x4e\x38\xf9\xa8\x0d\x7a\x6b\x82\x8c\x47\x0b\xd7\x72\xce\x2d"
      "\x53\x4a\x33\x55\x3a\xf8\xce\x68\x54\x33\xa6\x09\x04\xa0\x09\x10\xbf\x7e"
      "\xb0\x70\x09\x05\x04\x10\x40\x00\x09\x08\x0f\x09\x05\x00\x03\xff\x03\x09"
      "\x00\x01\xd2\x20\x31\xab\x6c\xe3\x6d\xea\xd3\x58\x93\x10\x25\xff\xa7\xd6"
      "\x46\xcd\x5b\x74\x8d\x19",
      294);
  *(uint32_t*)0x20000640 = 0;
  *(uint64_t*)0x20000644 = 0;
  *(uint32_t*)0x2000064c = 0;
  *(uint64_t*)0x20000650 = 0;
  *(uint32_t*)0x20000658 = 0;
  syz_usb_connect(/*speed=USB_SPEED_FULL*/ 2, /*dev_len=*/0xd55,
                  /*dev=*/0x200017c0, /*conn_descs=*/0x20000640);
  return 0;
}

Attachment: .config
Description: XML document

Attachment: kernel.log
Description: Binary data

Attachment: report
Description: Binary data

Attachment: repro.syz
Description: Binary data