Thank you Nam,
On 8/16/25 3:59 PM, Nam Cao wrote:
> On Sat, Aug 16, 2025 at 11:38:14AM +0900, Yunseong Kim wrote:
>> While testing a PREEMPT_RT enabled kernel (based on v6.17.0-rc1),
>> I encountered a "BUG: sleeping function called from invalid context" error
>> originating from the dummy_dequeue function in the dummy USB driver.
> ...
>> The pattern of manually disabling IRQs and then taking a spinlock
>> local_irq_save() + spin_lock() is unsafe on PREEMPT_RT, the current code
>> structure keeps IRQs disabled even after spin_unlock(&dum->lock) while
>> calling usb_gadget_giveback_request(). This extended atomic context can
>> also be problematic if the completion handler attempts to acquire another
>> sleepable lock.
>
> I don't know the USB subsystem well, but the comments above struct
> usb_request says:
>
> * @complete: Function called when request completes, so this request and
> * its buffer may be re-used. The function will always be called with
> * interrupts disabled, and it must not sleep.
>
> Therefore it shouldn't be a concern that "completion handler attempts to
> acquire another sleepable lock".
>
>> I request a review and correction of this locking mechanism to ensure
>> stability on PREEMPT_RT configurations. Kernel config, full logs, and
>> reproduction steps can be provided on request.
>
> This was introduced by b4dbda1a22d2 ("USB: dummy-hcd: disable interrupts
> during req->complete") which split the spin_lock_irqsave() into
> local_irq_save() and spin_lock().
>
> The untested patch below should help?
>
> Enabling interrupt (spin_unlock_irqrestore) and then immediately disabling
> interrupt (local_irq_save) is not the nicest thing. But then I don't see
> how to avoid that while being non-hacky and human-readable.
>
> Nam
Oh, I see! I’ll apply the patch and check if it reproduces the issue.
> diff --git a/drivers/usb/gadget/udc/dummy_hcd.c b/drivers/usb/gadget/udc/dummy_hcd.c
> index 21dbfb0b3bac..a4653c919664 100644
> --- a/drivers/usb/gadget/udc/dummy_hcd.c
> +++ b/drivers/usb/gadget/udc/dummy_hcd.c
> @@ -765,8 +765,7 @@ static int dummy_dequeue(struct usb_ep *_ep, struct usb_request *_req)
> if (!dum->driver)
> return -ESHUTDOWN;
>
> - local_irq_save(flags);
> - spin_lock(&dum->lock);
> + spin_lock_irqsave(&dum->lock, flags);
> list_for_each_entry(iter, &ep->queue, queue) {
> if (&iter->req != _req)
> continue;
> @@ -776,15 +775,16 @@ static int dummy_dequeue(struct usb_ep *_ep, struct usb_request *_req)
> retval = 0;
> break;
> }
> - spin_unlock(&dum->lock);
> + spin_unlock_irqrestore(&dum->lock, flags);
>
> if (retval == 0) {
> dev_dbg(udc_dev(dum),
> "dequeued req %p from %s, len %d buf %p\n",
> req, _ep->name, _req->length, _req->buf);
> + local_irq_save(flags);
> usb_gadget_giveback_request(_ep, _req);
> + local_irq_restore(flags);
> }
> - local_irq_restore(flags);
> return retval;
> }
>
This is reproducer for syzlang:
r0 = syz_usb_connect(0x0, 0x24, &(0x7f0000000000)={{0x12, 0x1, 0x0, 0x97, 0xff, 0x82, 0x8, 0x2058, 0x1005, 0xc19b, 0x0, 0x0, 0x0, 0x1, [{{0x9, 0x2, 0x12, 0x1, 0x0, 0x0, 0x0, 0x0, [{{0x9, 0x4, 0x8f, 0x0, 0x0, 0xbf, 0x57, 0x5a}}]}}]}}, 0x0)
syz_usb_control_io$cdc_ncm(r0, &(0x7f0000000100)={0x14, &(0x7f0000000040)={0x40, 0x0, 0x66, {0x66, 0x23, "6f2c18388112efffc4889080ab31f0d2984565049864502a1901c1114c7de30280e1de22288286cbc96de93149c64ba40c486c6d8618f867660d217efe65d204e4284c884ff6b3326cdc124b3c444b7897f53d604ca3ecf79ad0a1360b963987489ad1d1"}}, &(0x7f00000000c0)={0x0, 0x3, 0x1a, {0x1a}}}, &(0x7f0000000400)={0x44, &(0x7f0000000140)={0x40, 0x6, 0xc9, "e839c62caa4b30555c01ce5505144112eb8d7923383a6acbd7b1071c0b04359674d10837182419a1be1791ea591049213cbcead05c73d3029f9d72863d816c862b8f48760664abc2bf72b5b9567aa1fc9b102137d0c8a2c4d89347359b0fd81f0f1ec8ad4eb16b5d8860175c6f22214831828eead648503705b5eb201243a6adea26451b3ef72e6326cf80d579773dc52b167dbb56efa41ed5092b8b20904c8aa28bdba20aad3ac4859191490901edaa2a4b62452f9e84f219de47c767a852e96ed3c760c0431c3423"}, &(0x7f0000000240)={0x0, 0xa, 0x1, 0x8}, &(0x7f0000000280)={0x0, 0x8, 0x1, 0x9}, &(0x7f00000002c0)={0x20, 0x80, 0x1c, {0x4b, 0x8, 0x8, 0x2, 0x7, 0xc373, 0x8, 0xe, 0x2, 0x80, 0x112, 0x4c}}, &(0x7f0000000300)={0x20, 0x85, 0x4, 0x91f409a}, &(0x7f0000000340)={0x20, 0x83, 0x2, 0x1}, &(0x7f0000000380)={0x20, 0x87, 0x2, 0x9}, &(0x7f00000003c0)={0x20, 0x89, 0x2, 0x1}})
This is reproducer for C:
// 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>
#ifndef __NR_mmap
#define __NR_mmap 222
#endif
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;
}
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(const struct vusb_descriptors* descs,
const 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;
}
#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);
}
static int lookup_interface(int fd, uint8_t bInterfaceNumber,
uint8_t bAlternateSetting)
{
struct usb_device_index* index = lookup_usb_index(fd);
if (!index)
return -1;
for (int i = 0; i < index->ifaces_num; i++) {
if (index->ifaces[i].bInterfaceNumber == bInterfaceNumber &&
index->ifaces[i].bAlternateSetting == bAlternateSetting)
return i;
}
return -1;
}
#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);
}
static volatile long syz_usb_control_io(volatile long a0, volatile long a1,
volatile long a2)
{
int fd = a0;
const struct vusb_descriptors* descs = (const struct vusb_descriptors*)a1;
const struct vusb_responses* resps = (const struct vusb_responses*)a2;
struct usb_raw_control_event event;
event.inner.type = 0;
event.inner.length = USB_MAX_PACKET_SIZE;
int rv = usb_raw_event_fetch(fd, (struct usb_raw_event*)&event);
if (rv < 0) {
return rv;
}
if (event.inner.type != USB_RAW_EVENT_CONTROL) {
return -1;
}
char* response_data = NULL;
uint32_t response_length = 0;
if ((event.ctrl.bRequestType & USB_DIR_IN) && event.ctrl.wLength) {
if (!lookup_control_response(descs, resps, &event.ctrl, &response_data,
&response_length)) {
usb_raw_ep0_stall(fd);
return -1;
}
} else {
if ((event.ctrl.bRequestType & USB_TYPE_MASK) == USB_TYPE_STANDARD ||
event.ctrl.bRequest == USB_REQ_SET_INTERFACE) {
int iface_num = event.ctrl.wIndex;
int alt_set = event.ctrl.wValue;
int iface_index = lookup_interface(fd, iface_num, alt_set);
if (iface_index < 0) {
} else {
set_interface(fd, iface_index);
}
}
response_length = event.ctrl.wLength;
}
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;
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_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 0;
}
uint64_t r[1] = {0xffffffffffffffff};
int main(void)
{
syscall(__NR_mmap, /*addr=*/0x1ffff000ul, /*len=*/0x1000ul, /*prot=*/0ul,
/*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul,
/*fd=*/(intptr_t)-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=*/(intptr_t)-1, /*offset=*/0ul);
syscall(__NR_mmap, /*addr=*/0x21000000ul, /*len=*/0x1000ul, /*prot=*/0ul,
/*flags=MAP_FIXED|MAP_ANONYMOUS|MAP_PRIVATE*/ 0x32ul,
/*fd=*/(intptr_t)-1, /*offset=*/0ul);
const char* reason;
(void)reason;
intptr_t res = 0;
if (write(1, "executing program\n", sizeof("executing program\n") - 1)) {
}
// syz_usb_connect arguments: [
// speed: usb_device_speed = 0x0 (8 bytes)
// dev_len: len = 0x24 (8 bytes)
// dev: ptr[in, usb_device_descriptor] {
// usb_device_descriptor {
// inner: usb_device_descriptor_verbose_t[flags[usb_versions, int16],
// 0, 0, 0, flags[usb_device_max_packet_sizes, int8], 0, 0, 0,
// array[usb_config_descriptor, 1]] {
// bLength: const = 0x12 (1 bytes)
// bDescriptorType: const = 0x1 (1 bytes)
// bcdUSB: usb_versions = 0x0 (2 bytes)
// bDeviceClass: const = 0x97 (1 bytes)
// bDeviceSubClass: const = 0xff (1 bytes)
// bDeviceProtocol: const = 0x82 (1 bytes)
// bMaxPacketSize0: usb_device_max_packet_sizes = 0x8 (1 bytes)
// idVendor: const = 0x2058 (2 bytes)
// idProduct: const = 0x1005 (2 bytes)
// bcdDevice: const = 0xc19b (2 bytes)
// iManufacturer: const = 0x0 (1 bytes)
// iProduct: const = 0x0 (1 bytes)
// iSerialNumber: const = 0x0 (1 bytes)
// bNumConfigurations: len = 0x1 (1 bytes)
// configs: array[usb_config_descriptor] {
// usb_config_descriptor {
// inner: usb_config_descriptor_verbose_t[int8, len[interfaces,
// int8], int8, flags[usb_config_attributes, int8], int8,
// array[usb_interface_descriptor, 1:4]] {
// bLength: const = 0x9 (1 bytes)
// bDescriptorType: const = 0x2 (1 bytes)
// wTotalLength: len = 0x12 (2 bytes)
// bNumInterfaces: len = 0x1 (1 bytes)
// bConfigurationValue: int8 = 0x0 (1 bytes)
// iConfiguration: int8 = 0x0 (1 bytes)
// bmAttributes: usb_config_attributes = 0x0 (1 bytes)
// bMaxPower: int8 = 0x0 (1 bytes)
// interfaces: array[usb_interface_descriptor] {
// usb_interface_descriptor {
// inner: usb_interface_descriptor_verbose_t[int8, int8,
// len[endpoints, int8], const[0, int8], const[0, int8],
// const[0, int8], int8,
// array[usb_interface_extra_descriptor, 0:2],
// array[usb_endpoint_descriptor, 0:16]] {
// bLength: const = 0x9 (1 bytes)
// bDescriptorType: const = 0x4 (1 bytes)
// bInterfaceNumber: int8 = 0x8f (1 bytes)
// bAlternateSetting: int8 = 0x0 (1 bytes)
// bNumEndpoints: len = 0x0 (1 bytes)
// bInterfaceClass: const = 0xbf (1 bytes)
// bInterfaceSubClass: const = 0x57 (1 bytes)
// bInterfaceProtocol: const = 0x5a (1 bytes)
// iInterface: int8 = 0x0 (1 bytes)
// extra: array[usb_interface_extra_descriptor] {
// }
// endpoints: array[usb_endpoint_descriptor] {
// }
// }
// }
// }
// }
// }
// }
// }
// }
// }
// conn_descs: nil
// ]
// returns fd_usb
*(uint8_t*)0x20000000 = 0x12;
*(uint8_t*)0x20000001 = 1;
*(uint16_t*)0x20000002 = 0;
*(uint8_t*)0x20000004 = 0x97;
*(uint8_t*)0x20000005 = -1;
*(uint8_t*)0x20000006 = 0x82;
*(uint8_t*)0x20000007 = 8;
*(uint16_t*)0x20000008 = 0x2058;
*(uint16_t*)0x2000000a = 0x1005;
*(uint16_t*)0x2000000c = 0xc19b;
*(uint8_t*)0x2000000e = 0;
*(uint8_t*)0x2000000f = 0;
*(uint8_t*)0x20000010 = 0;
*(uint8_t*)0x20000011 = 1;
*(uint8_t*)0x20000012 = 9;
*(uint8_t*)0x20000013 = 2;
*(uint16_t*)0x20000014 = 0x12;
*(uint8_t*)0x20000016 = 1;
*(uint8_t*)0x20000017 = 0;
*(uint8_t*)0x20000018 = 0;
*(uint8_t*)0x20000019 = 0;
*(uint8_t*)0x2000001a = 0;
*(uint8_t*)0x2000001b = 9;
*(uint8_t*)0x2000001c = 4;
*(uint8_t*)0x2000001d = 0x8f;
*(uint8_t*)0x2000001e = 0;
*(uint8_t*)0x2000001f = 0;
*(uint8_t*)0x20000020 = 0xbf;
*(uint8_t*)0x20000021 = 0x57;
*(uint8_t*)0x20000022 = 0x5a;
*(uint8_t*)0x20000023 = 0;
res = -1;
res = syz_usb_connect(/*speed=*/0, /*dev_len=*/0x24, /*dev=*/0x20000000,
/*conn_descs=*/0);
if (res != -1)
r[0] = res;
// syz_usb_control_io$cdc_ncm arguments: [
// fd: fd_usb_cdc_ncm (resource)
// descs: ptr[in, vusb_descriptors_cdc_ncm] {
// vusb_descriptors_cdc_ncm {
// len: len = 0x14 (4 bytes)
// generic: ptr[in, vusb_descriptor_generic] {
// vusb_descriptor_generic {
// req_type: usb_request_types = 0x40 (1 bytes)
// desc_type: usb_descriptor_types = 0x0 (1 bytes)
// len: bytesize = 0x66 (4 bytes)
// data: usb_generic_descriptor {
// bLength: len = 0x66 (1 bytes)
// bDescriptorType: usb_descriptor_types = 0x23 (1 bytes)
// data: buffer: {6f 2c 18 38 81 12 ef ff c4 88 90 80 ab 31 f0 d2
// 98 45 65 04 98 64 50 2a 19 01 c1 11 4c 7d e3 02 80 e1 de 22 28
// 82 86 cb c9 6d e9 31 49 c6 4b a4 0c 48 6c 6d 86 18 f8 67 66 0d
// 21 7e fe 65 d2 04 e4 28 4c 88 4f f6 b3 32 6c dc 12 4b 3c 44 4b
// 78 97 f5 3d 60 4c a3 ec f7 9a d0 a1 36 0b 96 39 87 48 9a d1
// d1} (length 0x64)
// }
// }
// }
// USB_DT_STRING: ptr[in, vusb_descriptor_t[USB_TYPE_STANDARD,
// USB_DT_STRING, usb_string_descriptor_t[usb_cdc_ecm_mac]]] {
// vusb_descriptor_t[USB_TYPE_STANDARD, USB_DT_STRING,
// usb_string_descriptor_t[usb_cdc_ecm_mac]] {
// type: const = 0x0 (1 bytes)
// req: const = 0x3 (1 bytes)
// len: bytesize = 0x1a (4 bytes)
// data: usb_string_descriptor_t[usb_cdc_ecm_mac] {
// bLength: len = 0x1a (1 bytes)
// bDescriptorType: const = 0x3 (1 bytes)
// data: usb_cdc_ecm_mac {
// data0: const = 0x3400320034003200 (8 bytes)
// data1: const = 0x3400320034003200 (8 bytes)
// data2: const = 0x3400320034003200 (8 bytes)
// }
// }
// }
// }
// }
// }
// resps: ptr[in, vusb_responses_cdc_ncm] {
// vusb_responses_cdc_ncm {
// len: len = 0x44 (4 bytes)
// generic: ptr[in, vusb_response_generic] {
// vusb_response_generic {
// type: usb_request_types = 0x40 (1 bytes)
// req: usb_requests = 0x6 (1 bytes)
// len: bytesize = 0xc9 (4 bytes)
// data: buffer: {e8 39 c6 2c aa 4b 30 55 5c 01 ce 55 05 14 41 12
// eb 8d 79 23 38 3a 6a cb d7 b1 07 1c 0b 04 35 96 74 d1 08 37 18
// 24 19 a1 be 17 91 ea 59 10 49 21 3c bc ea d0 5c 73 d3 02 9f 9d
// 72 86 3d 81 6c 86 2b 8f 48 76 06 64 ab c2 bf 72 b5 b9 56 7a a1
// fc 9b 10 21 37 d0 c8 a2 c4 d8 93 47 35 9b 0f d8 1f 0f 1e c8 ad
// 4e b1 6b 5d 88 60 17 5c 6f 22 21 48 31 82 8e ea d6 48 50 37 05
// b5 eb 20 12 43 a6 ad ea 26 45 1b 3e f7 2e 63 26 cf 80 d5 79 77
// 3d c5 2b 16 7d bb 56 ef a4 1e d5 09 2b 8b 20 90 4c 8a a2 8b db
// a2 0a ad 3a c4 85 91 91 49 09 01 ed aa 2a 4b 62 45 2f 9e 84 f2
// 19 de 47 c7 67 a8 52 e9 6e d3 c7 60 c0 43 1c 34 23} (length
// 0xc9)
// }
// }
// USB_REQ_GET_INTERFACE: ptr[in, vusb_response_t[USB_TYPE_STANDARD,
// USB_REQ_GET_INTERFACE, int8]] {
// vusb_response_t[USB_TYPE_STANDARD, USB_REQ_GET_INTERFACE, int8] {
// type: const = 0x0 (1 bytes)
// req: const = 0xa (1 bytes)
// len: bytesize = 0x1 (4 bytes)
// data: int8 = 0x8 (1 bytes)
// }
// }
// USB_REQ_GET_CONFIGURATION: ptr[in,
// vusb_response_t[USB_TYPE_STANDARD, USB_REQ_GET_CONFIGURATION, int8]]
// {
// vusb_response_t[USB_TYPE_STANDARD, USB_REQ_GET_CONFIGURATION,
// int8] {
// type: const = 0x0 (1 bytes)
// req: const = 0x8 (1 bytes)
// len: bytesize = 0x1 (4 bytes)
// data: int8 = 0x9 (1 bytes)
// }
// }
// USB_CDC_GET_NTB_PARAMETERS: ptr[in, vusb_response_t[USB_TYPE_CLASS,
// USB_CDC_GET_NTB_PARAMETERS, usb_cdc_ncm_ntb_parameters]] {
// vusb_response_t[USB_TYPE_CLASS, USB_CDC_GET_NTB_PARAMETERS,
// usb_cdc_ncm_ntb_parameters] {
// type: const = 0x20 (1 bytes)
// req: const = 0x80 (1 bytes)
// len: bytesize = 0x1c (4 bytes)
// data: usb_cdc_ncm_ntb_parameters {
// wLength: int16 = 0x4b (2 bytes)
// bmNtbFormatsSupported: int16 = 0x8 (2 bytes)
// dwNtbInMaxSize: int32 = 0x8 (4 bytes)
// wNdpInDivisor: int16 = 0x2 (2 bytes)
// wNdpInPayloadRemainder: int16 = 0x7 (2 bytes)
// wNdpInAlignment: int16 = 0xc373 (2 bytes)
// wPadding1: int16 = 0x8 (2 bytes)
// dwNtbOutMaxSize: int32 = 0xe (4 bytes)
// wNdpOutDivisor: int16 = 0x2 (2 bytes)
// wNdpOutPayloadRemainder: int16 = 0x80 (2 bytes)
// wNdpOutAlignment: int16 = 0x112 (2 bytes)
// wNtbOutMaxDatagrams: int16 = 0x4c (2 bytes)
// }
// }
// }
// USB_CDC_GET_NTB_INPUT_SIZE: ptr[in, vusb_response_t[USB_TYPE_CLASS,
// USB_CDC_GET_NTB_INPUT_SIZE, int32]] {
// vusb_response_t[USB_TYPE_CLASS, USB_CDC_GET_NTB_INPUT_SIZE, int32]
// {
// type: const = 0x20 (1 bytes)
// req: const = 0x85 (1 bytes)
// len: bytesize = 0x4 (4 bytes)
// data: int32 = 0x91f409a (4 bytes)
// }
// }
// USB_CDC_GET_NTB_FORMAT: ptr[in, vusb_response_t[USB_TYPE_CLASS,
// USB_CDC_GET_NTB_FORMAT, int16[0:1]]] {
// vusb_response_t[USB_TYPE_CLASS, USB_CDC_GET_NTB_FORMAT,
// int16[0:1]] {
// type: const = 0x20 (1 bytes)
// req: const = 0x83 (1 bytes)
// len: bytesize = 0x2 (4 bytes)
// data: int16 = 0x1 (2 bytes)
// }
// }
// USB_CDC_GET_MAX_DATAGRAM_SIZE: ptr[in,
// vusb_response_t[USB_TYPE_CLASS, USB_CDC_GET_MAX_DATAGRAM_SIZE,
// int16]] {
// vusb_response_t[USB_TYPE_CLASS, USB_CDC_GET_MAX_DATAGRAM_SIZE,
// int16] {
// type: const = 0x20 (1 bytes)
// req: const = 0x87 (1 bytes)
// len: bytesize = 0x2 (4 bytes)
// data: int16 = 0x9 (2 bytes)
// }
// }
// USB_CDC_GET_CRC_MODE: ptr[in, vusb_response_t[USB_TYPE_CLASS,
// USB_CDC_GET_CRC_MODE, int16[0:1]]] {
// vusb_response_t[USB_TYPE_CLASS, USB_CDC_GET_CRC_MODE, int16[0:1]]
// {
// type: const = 0x20 (1 bytes)
// req: const = 0x89 (1 bytes)
// len: bytesize = 0x2 (4 bytes)
// data: int16 = 0x1 (2 bytes)
// }
// }
// }
// }
// ]
*(uint32_t*)0x20000100 = 0x14;
*(uint64_t*)0x20000104 = 0x20000040;
*(uint8_t*)0x20000040 = 0x40;
*(uint8_t*)0x20000041 = 0;
*(uint32_t*)0x20000042 = 0x66;
*(uint8_t*)0x20000046 = 0x66;
*(uint8_t*)0x20000047 = 0x23;
memcpy((void*)0x20000048,
"\x6f\x2c\x18\x38\x81\x12\xef\xff\xc4\x88\x90\x80\xab\x31\xf0\xd2\x98"
"\x45\x65\x04\x98\x64\x50\x2a\x19\x01\xc1\x11\x4c\x7d\xe3\x02\x80\xe1"
"\xde\x22\x28\x82\x86\xcb\xc9\x6d\xe9\x31\x49\xc6\x4b\xa4\x0c\x48\x6c"
"\x6d\x86\x18\xf8\x67\x66\x0d\x21\x7e\xfe\x65\xd2\x04\xe4\x28\x4c\x88"
"\x4f\xf6\xb3\x32\x6c\xdc\x12\x4b\x3c\x44\x4b\x78\x97\xf5\x3d\x60\x4c"
"\xa3\xec\xf7\x9a\xd0\xa1\x36\x0b\x96\x39\x87\x48\x9a\xd1\xd1",
100);
*(uint64_t*)0x2000010c = 0x200000c0;
*(uint8_t*)0x200000c0 = 0;
*(uint8_t*)0x200000c1 = 3;
*(uint32_t*)0x200000c2 = 0x1a;
*(uint8_t*)0x200000c6 = 0x1a;
*(uint8_t*)0x200000c7 = 3;
*(uint64_t*)0x200000c8 = htobe64(0x3400320034003200);
*(uint64_t*)0x200000d0 = htobe64(0x3400320034003200);
*(uint64_t*)0x200000d8 = htobe64(0x3400320034003200);
*(uint32_t*)0x20000400 = 0x44;
*(uint64_t*)0x20000404 = 0x20000140;
*(uint8_t*)0x20000140 = 0x40;
*(uint8_t*)0x20000141 = 6;
*(uint32_t*)0x20000142 = 0xc9;
memcpy((void*)0x20000146,
"\xe8\x39\xc6\x2c\xaa\x4b\x30\x55\x5c\x01\xce\x55\x05\x14\x41\x12\xeb"
"\x8d\x79\x23\x38\x3a\x6a\xcb\xd7\xb1\x07\x1c\x0b\x04\x35\x96\x74\xd1"
"\x08\x37\x18\x24\x19\xa1\xbe\x17\x91\xea\x59\x10\x49\x21\x3c\xbc\xea"
"\xd0\x5c\x73\xd3\x02\x9f\x9d\x72\x86\x3d\x81\x6c\x86\x2b\x8f\x48\x76"
"\x06\x64\xab\xc2\xbf\x72\xb5\xb9\x56\x7a\xa1\xfc\x9b\x10\x21\x37\xd0"
"\xc8\xa2\xc4\xd8\x93\x47\x35\x9b\x0f\xd8\x1f\x0f\x1e\xc8\xad\x4e\xb1"
"\x6b\x5d\x88\x60\x17\x5c\x6f\x22\x21\x48\x31\x82\x8e\xea\xd6\x48\x50"
"\x37\x05\xb5\xeb\x20\x12\x43\xa6\xad\xea\x26\x45\x1b\x3e\xf7\x2e\x63"
"\x26\xcf\x80\xd5\x79\x77\x3d\xc5\x2b\x16\x7d\xbb\x56\xef\xa4\x1e\xd5"
"\x09\x2b\x8b\x20\x90\x4c\x8a\xa2\x8b\xdb\xa2\x0a\xad\x3a\xc4\x85\x91"
"\x91\x49\x09\x01\xed\xaa\x2a\x4b\x62\x45\x2f\x9e\x84\xf2\x19\xde\x47"
"\xc7\x67\xa8\x52\xe9\x6e\xd3\xc7\x60\xc0\x43\x1c\x34\x23",
201);
*(uint64_t*)0x2000040c = 0x20000240;
*(uint8_t*)0x20000240 = 0;
*(uint8_t*)0x20000241 = 0xa;
*(uint32_t*)0x20000242 = 1;
*(uint8_t*)0x20000246 = 8;
*(uint64_t*)0x20000414 = 0x20000280;
*(uint8_t*)0x20000280 = 0;
*(uint8_t*)0x20000281 = 8;
*(uint32_t*)0x20000282 = 1;
*(uint8_t*)0x20000286 = 9;
*(uint64_t*)0x2000041c = 0x200002c0;
*(uint8_t*)0x200002c0 = 0x20;
*(uint8_t*)0x200002c1 = 0x80;
*(uint32_t*)0x200002c2 = 0x1c;
*(uint16_t*)0x200002c6 = 0x4b;
*(uint16_t*)0x200002c8 = 8;
*(uint32_t*)0x200002ca = 8;
*(uint16_t*)0x200002ce = 2;
*(uint16_t*)0x200002d0 = 7;
*(uint16_t*)0x200002d2 = 0xc373;
*(uint16_t*)0x200002d4 = 8;
*(uint32_t*)0x200002d6 = 0xe;
*(uint16_t*)0x200002da = 2;
*(uint16_t*)0x200002dc = 0x80;
*(uint16_t*)0x200002de = 0x112;
*(uint16_t*)0x200002e0 = 0x4c;
*(uint64_t*)0x20000424 = 0x20000300;
*(uint8_t*)0x20000300 = 0x20;
*(uint8_t*)0x20000301 = 0x85;
*(uint32_t*)0x20000302 = 4;
*(uint32_t*)0x20000306 = 0x91f409a;
*(uint64_t*)0x2000042c = 0x20000340;
*(uint8_t*)0x20000340 = 0x20;
*(uint8_t*)0x20000341 = 0x83;
*(uint32_t*)0x20000342 = 2;
*(uint16_t*)0x20000346 = 1;
*(uint64_t*)0x20000434 = 0x20000380;
*(uint8_t*)0x20000380 = 0x20;
*(uint8_t*)0x20000381 = 0x87;
*(uint32_t*)0x20000382 = 2;
*(uint16_t*)0x20000386 = 9;
*(uint64_t*)0x2000043c = 0x200003c0;
*(uint8_t*)0x200003c0 = 0x20;
*(uint8_t*)0x200003c1 = 0x89;
*(uint32_t*)0x200003c2 = 2;
*(uint16_t*)0x200003c6 = 1;
syz_usb_control_io(/*fd=*/r[0], /*descs=*/0x20000100, /*resps=*/0x20000400);
return 0;
}
Thank you!
Best regards,
Yunseong
