Need help in debugging "memory leak in em28xx_init_dev"
From: Dongliang Mu
Date: Sun Oct 31 2021 - 23:03:09 EST
Hi all,
My local syzkaller instance found one bug named "memory leak in
em28xx_init_dev" in 5.14-rc5. Kernel configuration and PoC file are
attached(I don't check if the latest kernel is vulnerable, but it
should be). The trace from memleak is as follows:
backtrace:
[<ffffffff842cc66d>] kmalloc include/linux/slab.h:591 [inline]
[<ffffffff842cc66d>] kzalloc include/linux/slab.h:721 [inline]
[<ffffffff842cc66d>] em28xx_media_device_init
drivers/media/usb/em28xx/em28xx-cards.c:3444 [inline]
[<ffffffff842cc66d>] em28xx_init_dev.isra.0+0x366/0x9bf
drivers/media/usb/em28xx/em28xx-cards.c:3624
[<ffffffff842cd1bd>] em28xx_usb_probe.cold+0x4f7/0xf95
drivers/media/usb/em28xx/em28xx-cards.c:3979
[<ffffffff82bf0815>] usb_probe_interface+0x185/0x350
drivers/usb/core/driver.c:396
After debugging this bug, I found a wired phenomenon: em28xx_usb_probe
is executed, but its disconnect function is not executed.
static struct usb_driver em28xx_usb_driver = {
.name = "em28xx",
.probe = em28xx_usb_probe,
.disconnect = em28xx_usb_disconnect,
......
};
Then a moment later(debugging), I found the problem can be that
device_driver is incorrect as the remove function does not lead to
disconnect function (em28xx_usb_disconnect).
$14 = {name = 0xffffffff8548fcc9 "usb", bus = 0xffffffff864fd1e0
<usb_bus_type>, owner = 0x0 <fixed_percpu_data>, mod_name = 0x0
<fixed_percpu_data>, probe = 0xffffffff82bf0570 <usb_probe_device>,
remove = 0xffffffff82beed90 <usb_unbind_device>,...}
Actually, the device_driver should have the following content:
$16 = {name = 0xffffffff854ea723 "em28xx", bus = 0xffffffff864fd1e0
<usb_bus_type>, owner = 0x0 <fixed_percpu_data>, mod_name =
0xffffffff854ea723 "em28xx", probe = 0xffffffff82bf0690
<usb_probe_interface>, remove = 0xffffffff82befb60
<usb_unbind_interface>, ...}
After manually reviewing some code, I found two similar functions:
usb_register_device_driver and usb_register_driver. The former sets
probe and remove like this,
new_udriver->drvwrap.driver.probe = usb_probe_device;
new_udriver->drvwrap.driver.remove = usb_unbind_device;
The latter sets probe and remove like this,
new_driver->drvwrap.driver.probe = usb_probe_interface;
new_driver->drvwrap.driver.remove = usb_unbind_interface;
And in debugging, I found another interesting point: if you "waste"
some time after em28xx_usb_probe, the device driver would be correct.
Any suggestion on the debugging of the above bug?
--
My best regards to you.
No System Is Safe!
Dongliang Mu
// 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>
static 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 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 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;
}
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;
}
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,
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:
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_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);
}
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;
}
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;
}
#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 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;
if (event.ctrl.bRequestType & USB_DIR_IN) {
if (!lookup_connect_response_in(fd, descs, &event.ctrl, &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;
}
static void kill_and_wait(int pid, int* status)
{
kill(-pid, SIGKILL);
kill(pid, SIGKILL);
for (int 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");
}
#define KMEMLEAK_FILE "/sys/kernel/debug/kmemleak"
static void setup_leak()
{
if (!write_file(KMEMLEAK_FILE, "scan"))
exit(1);
sleep(5);
if (!write_file(KMEMLEAK_FILE, "scan"))
exit(1);
if (!write_file(KMEMLEAK_FILE, "clear"))
exit(1);
}
static void check_leaks(void)
{
int fd = open(KMEMLEAK_FILE, O_RDWR);
if (fd == -1)
exit(1);
uint64_t start = current_time_ms();
if (write(fd, "scan", 4) != 4)
exit(1);
sleep(1);
while (current_time_ms() - start < 4 * 1000)
sleep(1);
if (write(fd, "scan", 4) != 4)
exit(1);
static char buf[128 << 10];
ssize_t n = read(fd, buf, sizeof(buf) - 1);
if (n < 0)
exit(1);
int nleaks = 0;
if (n != 0) {
sleep(1);
if (write(fd, "scan", 4) != 4)
exit(1);
if (lseek(fd, 0, SEEK_SET) < 0)
exit(1);
n = read(fd, buf, sizeof(buf) - 1);
if (n < 0)
exit(1);
buf[n] = 0;
char* pos = buf;
char* end = buf + n;
while (pos < end) {
char* next = strstr(pos + 1, "unreferenced object");
if (!next)
next = end;
char prev = *next;
*next = 0;
fprintf(stderr, "BUG: memory leak\n%s\n", pos);
*next = prev;
pos = next;
nleaks++;
}
}
if (write(fd, "clear", 5) != 5)
exit(1);
close(fd);
if (nleaks)
exit(1);
}
static void execute_one(void);
#define WAIT_FLAGS __WALL
static void loop(void)
{
int iter = 0;
for (;; 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 < 5000)
continue;
kill_and_wait(pid, &status);
break;
}
check_leaks();
}
}
uint64_t r[1] = {0xffffffffffffffff};
void execute_one(void)
{
intptr_t res = 0;
memcpy((void*)0x20000080, "\x12\x01\x00\x00\xbd\xa0\x4d\x10\x04\x23\x07\x02\x8b\xe7\x01\x02\x03\x01\x09\x02\x1b\x00\x01\x00\x00\x00\x00\x09\x04\x00\x00\x01\xd5\x53\x16\x00\x09\x05\x83\xf9", 40);
res = -1;
res = syz_usb_connect(0, 0x2d, 0x20000080, 0);
if (res != -1)
r[0] = res;
syz_usb_control_io(r[0], 0, 0);
syz_usb_control_io(r[0], 0, 0);
*(uint32_t*)0x20000180 = 0x84;
*(uint64_t*)0x20000184 = 0x200003c0;
*(uint8_t*)0x200003c0 = 0x40;
*(uint8_t*)0x200003c1 = 0;
*(uint32_t*)0x200003c2 = 0x82;
memcpy((void*)0x200003c6, "\xf0\x8c\x18\xde\x70\xe7\x7d\xa1\xea\x1a\x00\xd3\x0c\x67\x5c\x0e\x49\x0d\x4d\x7e\x43\x01\xd9\x88\x8a\x70\xfa\x01\x03\x7e\x17\x25\x16\xb6\x08\x78\x96\xa9\xa2\xdb\xd3\xfc\xf3\x89\xe7\x2a\xf9\x3c\x5b\x5f\xe3\xe0\x97\x25\xf0\x0e\xef\xd9\xa9\x18\x5e\x26\x85\x59\xc8\x30\x95\xa7\x53\xd8\x3c\xf8\x67\xcf\xeb\xf7\xe4\x5e\x0e\xd9\xe1\x08\x17\x23\xb8\x27\x4a\x39\xdb\x5a\xc6\x0b\x09\x58\x08\xef\xcd\x70\x71\x61\xbd\x23\xf6\xc2\xf3\x53\x1f\xd7\x35\x20\x2c\xf5\x48\x4f\x13\x9c\x14\xec\x0c\x4f\x6a\x47\xeb\xc0\x2d\xe6\x57\xdc\x83\x63", 130);
*(uint64_t*)0x2000018c = 0;
*(uint64_t*)0x20000194 = 0;
*(uint64_t*)0x2000019c = 0;
*(uint64_t*)0x200001a4 = 0;
*(uint64_t*)0x200001ac = 0;
*(uint64_t*)0x200001b4 = 0;
*(uint64_t*)0x200001bc = 0;
*(uint64_t*)0x200001c4 = 0;
*(uint64_t*)0x200001cc = 0;
*(uint64_t*)0x200001d4 = 0;
*(uint64_t*)0x200001dc = 0;
*(uint64_t*)0x200001e4 = 0;
*(uint64_t*)0x200001ec = 0;
*(uint64_t*)0x200001f4 = 0;
*(uint64_t*)0x200001fc = 0;
syz_usb_control_io(r[0], 0, 0x20000180);
}
int main(void)
{
syscall(__NR_mmap, 0x1ffff000ul, 0x1000ul, 0ul, 0x32ul, -1, 0ul);
syscall(__NR_mmap, 0x20000000ul, 0x1000000ul, 7ul, 0x32ul, -1, 0ul);
syscall(__NR_mmap, 0x21000000ul, 0x1000ul, 0ul, 0x32ul, -1, 0ul);
setup_leak();
loop();
return 0;
}
Attachment:
kernel_config
Description: Binary data