linux-stable/drivers/usb/core/sysfs.c
Zeng Tao a18cd6c9b6 usb: core: fix slab-out-of-bounds Read in read_descriptors
The USB device descriptor may get changed between two consecutive
enumerations on the same device for some reason, such as DFU or
malicius device.
In that case, we may access the changing descriptor if we don't take
the device lock here.

The issue is reported:
https://syzkaller.appspot.com/bug?id=901a0d9e6519ef8dc7acab25344bd287dd3c7be9

Cc: stable <stable@vger.kernel.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Reported-by: syzbot+256e56ddde8b8957eabd@syzkaller.appspotmail.com
Fixes: 217a9081d8 ("USB: add all configs to the "descriptors" attribute")
Signed-off-by: Zeng Tao <prime.zeng@hisilicon.com>
Link: https://lore.kernel.org/r/1599201467-11000-1-git-send-email-prime.zeng@hisilicon.com
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
2020-09-04 16:41:22 +02:00

1284 lines
32 KiB
C

// SPDX-License-Identifier: GPL-2.0
/*
* drivers/usb/core/sysfs.c
*
* (C) Copyright 2002 David Brownell
* (C) Copyright 2002,2004 Greg Kroah-Hartman
* (C) Copyright 2002,2004 IBM Corp.
*
* All of the sysfs file attributes for usb devices and interfaces.
*
* Released under the GPLv2 only.
*/
#include <linux/kernel.h>
#include <linux/string.h>
#include <linux/usb.h>
#include <linux/usb/hcd.h>
#include <linux/usb/quirks.h>
#include <linux/of.h>
#include "usb.h"
/* Active configuration fields */
#define usb_actconfig_show(field, format_string) \
static ssize_t field##_show(struct device *dev, \
struct device_attribute *attr, char *buf) \
{ \
struct usb_device *udev; \
struct usb_host_config *actconfig; \
ssize_t rc; \
\
udev = to_usb_device(dev); \
rc = usb_lock_device_interruptible(udev); \
if (rc < 0) \
return -EINTR; \
actconfig = udev->actconfig; \
if (actconfig) \
rc = sprintf(buf, format_string, \
actconfig->desc.field); \
usb_unlock_device(udev); \
return rc; \
} \
#define usb_actconfig_attr(field, format_string) \
usb_actconfig_show(field, format_string) \
static DEVICE_ATTR_RO(field)
usb_actconfig_attr(bNumInterfaces, "%2d\n");
usb_actconfig_attr(bmAttributes, "%2x\n");
static ssize_t bMaxPower_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct usb_device *udev;
struct usb_host_config *actconfig;
ssize_t rc;
udev = to_usb_device(dev);
rc = usb_lock_device_interruptible(udev);
if (rc < 0)
return -EINTR;
actconfig = udev->actconfig;
if (actconfig)
rc = sprintf(buf, "%dmA\n", usb_get_max_power(udev, actconfig));
usb_unlock_device(udev);
return rc;
}
static DEVICE_ATTR_RO(bMaxPower);
static ssize_t configuration_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct usb_device *udev;
struct usb_host_config *actconfig;
ssize_t rc;
udev = to_usb_device(dev);
rc = usb_lock_device_interruptible(udev);
if (rc < 0)
return -EINTR;
actconfig = udev->actconfig;
if (actconfig && actconfig->string)
rc = sprintf(buf, "%s\n", actconfig->string);
usb_unlock_device(udev);
return rc;
}
static DEVICE_ATTR_RO(configuration);
/* configuration value is always present, and r/w */
usb_actconfig_show(bConfigurationValue, "%u\n");
static ssize_t bConfigurationValue_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct usb_device *udev = to_usb_device(dev);
int config, value, rc;
if (sscanf(buf, "%d", &config) != 1 || config < -1 || config > 255)
return -EINVAL;
rc = usb_lock_device_interruptible(udev);
if (rc < 0)
return -EINTR;
value = usb_set_configuration(udev, config);
usb_unlock_device(udev);
return (value < 0) ? value : count;
}
static DEVICE_ATTR_IGNORE_LOCKDEP(bConfigurationValue, S_IRUGO | S_IWUSR,
bConfigurationValue_show, bConfigurationValue_store);
#ifdef CONFIG_OF
static ssize_t devspec_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct device_node *of_node = dev->of_node;
return sprintf(buf, "%pOF\n", of_node);
}
static DEVICE_ATTR_RO(devspec);
#endif
/* String fields */
#define usb_string_attr(name) \
static ssize_t name##_show(struct device *dev, \
struct device_attribute *attr, char *buf) \
{ \
struct usb_device *udev; \
int retval; \
\
udev = to_usb_device(dev); \
retval = usb_lock_device_interruptible(udev); \
if (retval < 0) \
return -EINTR; \
retval = sprintf(buf, "%s\n", udev->name); \
usb_unlock_device(udev); \
return retval; \
} \
static DEVICE_ATTR_RO(name)
usb_string_attr(product);
usb_string_attr(manufacturer);
usb_string_attr(serial);
static ssize_t speed_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct usb_device *udev;
char *speed;
udev = to_usb_device(dev);
switch (udev->speed) {
case USB_SPEED_LOW:
speed = "1.5";
break;
case USB_SPEED_UNKNOWN:
case USB_SPEED_FULL:
speed = "12";
break;
case USB_SPEED_HIGH:
speed = "480";
break;
case USB_SPEED_WIRELESS:
speed = "480";
break;
case USB_SPEED_SUPER:
speed = "5000";
break;
case USB_SPEED_SUPER_PLUS:
speed = "10000";
break;
default:
speed = "unknown";
}
return sprintf(buf, "%s\n", speed);
}
static DEVICE_ATTR_RO(speed);
static ssize_t rx_lanes_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct usb_device *udev;
udev = to_usb_device(dev);
return sprintf(buf, "%d\n", udev->rx_lanes);
}
static DEVICE_ATTR_RO(rx_lanes);
static ssize_t tx_lanes_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct usb_device *udev;
udev = to_usb_device(dev);
return sprintf(buf, "%d\n", udev->tx_lanes);
}
static DEVICE_ATTR_RO(tx_lanes);
static ssize_t busnum_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct usb_device *udev;
udev = to_usb_device(dev);
return sprintf(buf, "%d\n", udev->bus->busnum);
}
static DEVICE_ATTR_RO(busnum);
static ssize_t devnum_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct usb_device *udev;
udev = to_usb_device(dev);
return sprintf(buf, "%d\n", udev->devnum);
}
static DEVICE_ATTR_RO(devnum);
static ssize_t devpath_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct usb_device *udev;
udev = to_usb_device(dev);
return sprintf(buf, "%s\n", udev->devpath);
}
static DEVICE_ATTR_RO(devpath);
static ssize_t version_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct usb_device *udev;
u16 bcdUSB;
udev = to_usb_device(dev);
bcdUSB = le16_to_cpu(udev->descriptor.bcdUSB);
return sprintf(buf, "%2x.%02x\n", bcdUSB >> 8, bcdUSB & 0xff);
}
static DEVICE_ATTR_RO(version);
static ssize_t maxchild_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct usb_device *udev;
udev = to_usb_device(dev);
return sprintf(buf, "%d\n", udev->maxchild);
}
static DEVICE_ATTR_RO(maxchild);
static ssize_t quirks_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct usb_device *udev;
udev = to_usb_device(dev);
return sprintf(buf, "0x%x\n", udev->quirks);
}
static DEVICE_ATTR_RO(quirks);
static ssize_t avoid_reset_quirk_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct usb_device *udev;
udev = to_usb_device(dev);
return sprintf(buf, "%d\n", !!(udev->quirks & USB_QUIRK_RESET));
}
static ssize_t avoid_reset_quirk_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct usb_device *udev = to_usb_device(dev);
int val, rc;
if (sscanf(buf, "%d", &val) != 1 || val < 0 || val > 1)
return -EINVAL;
rc = usb_lock_device_interruptible(udev);
if (rc < 0)
return -EINTR;
if (val)
udev->quirks |= USB_QUIRK_RESET;
else
udev->quirks &= ~USB_QUIRK_RESET;
usb_unlock_device(udev);
return count;
}
static DEVICE_ATTR_RW(avoid_reset_quirk);
static ssize_t urbnum_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct usb_device *udev;
udev = to_usb_device(dev);
return sprintf(buf, "%d\n", atomic_read(&udev->urbnum));
}
static DEVICE_ATTR_RO(urbnum);
static ssize_t removable_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct usb_device *udev;
char *state;
udev = to_usb_device(dev);
switch (udev->removable) {
case USB_DEVICE_REMOVABLE:
state = "removable";
break;
case USB_DEVICE_FIXED:
state = "fixed";
break;
default:
state = "unknown";
}
return sprintf(buf, "%s\n", state);
}
static DEVICE_ATTR_RO(removable);
static ssize_t ltm_capable_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
if (usb_device_supports_ltm(to_usb_device(dev)))
return sprintf(buf, "%s\n", "yes");
return sprintf(buf, "%s\n", "no");
}
static DEVICE_ATTR_RO(ltm_capable);
#ifdef CONFIG_PM
static ssize_t persist_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct usb_device *udev = to_usb_device(dev);
return sprintf(buf, "%d\n", udev->persist_enabled);
}
static ssize_t persist_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct usb_device *udev = to_usb_device(dev);
int value, rc;
/* Hubs are always enabled for USB_PERSIST */
if (udev->descriptor.bDeviceClass == USB_CLASS_HUB)
return -EPERM;
if (sscanf(buf, "%d", &value) != 1)
return -EINVAL;
rc = usb_lock_device_interruptible(udev);
if (rc < 0)
return -EINTR;
udev->persist_enabled = !!value;
usb_unlock_device(udev);
return count;
}
static DEVICE_ATTR_RW(persist);
static int add_persist_attributes(struct device *dev)
{
int rc = 0;
if (is_usb_device(dev)) {
struct usb_device *udev = to_usb_device(dev);
/* Hubs are automatically enabled for USB_PERSIST,
* no point in creating the attribute file.
*/
if (udev->descriptor.bDeviceClass != USB_CLASS_HUB)
rc = sysfs_add_file_to_group(&dev->kobj,
&dev_attr_persist.attr,
power_group_name);
}
return rc;
}
static void remove_persist_attributes(struct device *dev)
{
sysfs_remove_file_from_group(&dev->kobj,
&dev_attr_persist.attr,
power_group_name);
}
static ssize_t connected_duration_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct usb_device *udev = to_usb_device(dev);
return sprintf(buf, "%u\n",
jiffies_to_msecs(jiffies - udev->connect_time));
}
static DEVICE_ATTR_RO(connected_duration);
/*
* If the device is resumed, the last time the device was suspended has
* been pre-subtracted from active_duration. We add the current time to
* get the duration that the device was actually active.
*
* If the device is suspended, the active_duration is up-to-date.
*/
static ssize_t active_duration_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct usb_device *udev = to_usb_device(dev);
int duration;
if (udev->state != USB_STATE_SUSPENDED)
duration = jiffies_to_msecs(jiffies + udev->active_duration);
else
duration = jiffies_to_msecs(udev->active_duration);
return sprintf(buf, "%u\n", duration);
}
static DEVICE_ATTR_RO(active_duration);
static ssize_t autosuspend_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
return sprintf(buf, "%d\n", dev->power.autosuspend_delay / 1000);
}
static ssize_t autosuspend_store(struct device *dev,
struct device_attribute *attr, const char *buf,
size_t count)
{
int value;
if (sscanf(buf, "%d", &value) != 1 || value >= INT_MAX/1000 ||
value <= -INT_MAX/1000)
return -EINVAL;
pm_runtime_set_autosuspend_delay(dev, value * 1000);
return count;
}
static DEVICE_ATTR_RW(autosuspend);
static const char on_string[] = "on";
static const char auto_string[] = "auto";
static void warn_level(void)
{
static int level_warned;
if (!level_warned) {
level_warned = 1;
printk(KERN_WARNING "WARNING! power/level is deprecated; "
"use power/control instead\n");
}
}
static ssize_t level_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct usb_device *udev = to_usb_device(dev);
const char *p = auto_string;
warn_level();
if (udev->state != USB_STATE_SUSPENDED && !udev->dev.power.runtime_auto)
p = on_string;
return sprintf(buf, "%s\n", p);
}
static ssize_t level_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct usb_device *udev = to_usb_device(dev);
int len = count;
char *cp;
int rc = count;
int rv;
warn_level();
cp = memchr(buf, '\n', count);
if (cp)
len = cp - buf;
rv = usb_lock_device_interruptible(udev);
if (rv < 0)
return -EINTR;
if (len == sizeof on_string - 1 &&
strncmp(buf, on_string, len) == 0)
usb_disable_autosuspend(udev);
else if (len == sizeof auto_string - 1 &&
strncmp(buf, auto_string, len) == 0)
usb_enable_autosuspend(udev);
else
rc = -EINVAL;
usb_unlock_device(udev);
return rc;
}
static DEVICE_ATTR_RW(level);
static ssize_t usb2_hardware_lpm_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct usb_device *udev = to_usb_device(dev);
const char *p;
if (udev->usb2_hw_lpm_allowed == 1)
p = "enabled";
else
p = "disabled";
return sprintf(buf, "%s\n", p);
}
static ssize_t usb2_hardware_lpm_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct usb_device *udev = to_usb_device(dev);
bool value;
int ret;
ret = usb_lock_device_interruptible(udev);
if (ret < 0)
return -EINTR;
ret = strtobool(buf, &value);
if (!ret) {
udev->usb2_hw_lpm_allowed = value;
if (value)
ret = usb_enable_usb2_hardware_lpm(udev);
else
ret = usb_disable_usb2_hardware_lpm(udev);
}
usb_unlock_device(udev);
if (!ret)
return count;
return ret;
}
static DEVICE_ATTR_RW(usb2_hardware_lpm);
static ssize_t usb2_lpm_l1_timeout_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
struct usb_device *udev = to_usb_device(dev);
return sprintf(buf, "%d\n", udev->l1_params.timeout);
}
static ssize_t usb2_lpm_l1_timeout_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct usb_device *udev = to_usb_device(dev);
u16 timeout;
if (kstrtou16(buf, 0, &timeout))
return -EINVAL;
udev->l1_params.timeout = timeout;
return count;
}
static DEVICE_ATTR_RW(usb2_lpm_l1_timeout);
static ssize_t usb2_lpm_besl_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct usb_device *udev = to_usb_device(dev);
return sprintf(buf, "%d\n", udev->l1_params.besl);
}
static ssize_t usb2_lpm_besl_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t count)
{
struct usb_device *udev = to_usb_device(dev);
u8 besl;
if (kstrtou8(buf, 0, &besl) || besl > 15)
return -EINVAL;
udev->l1_params.besl = besl;
return count;
}
static DEVICE_ATTR_RW(usb2_lpm_besl);
static ssize_t usb3_hardware_lpm_u1_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct usb_device *udev = to_usb_device(dev);
const char *p;
int rc;
rc = usb_lock_device_interruptible(udev);
if (rc < 0)
return -EINTR;
if (udev->usb3_lpm_u1_enabled)
p = "enabled";
else
p = "disabled";
usb_unlock_device(udev);
return sprintf(buf, "%s\n", p);
}
static DEVICE_ATTR_RO(usb3_hardware_lpm_u1);
static ssize_t usb3_hardware_lpm_u2_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct usb_device *udev = to_usb_device(dev);
const char *p;
int rc;
rc = usb_lock_device_interruptible(udev);
if (rc < 0)
return -EINTR;
if (udev->usb3_lpm_u2_enabled)
p = "enabled";
else
p = "disabled";
usb_unlock_device(udev);
return sprintf(buf, "%s\n", p);
}
static DEVICE_ATTR_RO(usb3_hardware_lpm_u2);
static struct attribute *usb2_hardware_lpm_attr[] = {
&dev_attr_usb2_hardware_lpm.attr,
&dev_attr_usb2_lpm_l1_timeout.attr,
&dev_attr_usb2_lpm_besl.attr,
NULL,
};
static struct attribute_group usb2_hardware_lpm_attr_group = {
.name = power_group_name,
.attrs = usb2_hardware_lpm_attr,
};
static struct attribute *usb3_hardware_lpm_attr[] = {
&dev_attr_usb3_hardware_lpm_u1.attr,
&dev_attr_usb3_hardware_lpm_u2.attr,
NULL,
};
static struct attribute_group usb3_hardware_lpm_attr_group = {
.name = power_group_name,
.attrs = usb3_hardware_lpm_attr,
};
static struct attribute *power_attrs[] = {
&dev_attr_autosuspend.attr,
&dev_attr_level.attr,
&dev_attr_connected_duration.attr,
&dev_attr_active_duration.attr,
NULL,
};
static struct attribute_group power_attr_group = {
.name = power_group_name,
.attrs = power_attrs,
};
static int add_power_attributes(struct device *dev)
{
int rc = 0;
if (is_usb_device(dev)) {
struct usb_device *udev = to_usb_device(dev);
rc = sysfs_merge_group(&dev->kobj, &power_attr_group);
if (udev->usb2_hw_lpm_capable == 1)
rc = sysfs_merge_group(&dev->kobj,
&usb2_hardware_lpm_attr_group);
if ((udev->speed == USB_SPEED_SUPER ||
udev->speed == USB_SPEED_SUPER_PLUS) &&
udev->lpm_capable == 1)
rc = sysfs_merge_group(&dev->kobj,
&usb3_hardware_lpm_attr_group);
}
return rc;
}
static void remove_power_attributes(struct device *dev)
{
sysfs_unmerge_group(&dev->kobj, &usb2_hardware_lpm_attr_group);
sysfs_unmerge_group(&dev->kobj, &power_attr_group);
}
#else
#define add_persist_attributes(dev) 0
#define remove_persist_attributes(dev) do {} while (0)
#define add_power_attributes(dev) 0
#define remove_power_attributes(dev) do {} while (0)
#endif /* CONFIG_PM */
/* Descriptor fields */
#define usb_descriptor_attr_le16(field, format_string) \
static ssize_t \
field##_show(struct device *dev, struct device_attribute *attr, \
char *buf) \
{ \
struct usb_device *udev; \
\
udev = to_usb_device(dev); \
return sprintf(buf, format_string, \
le16_to_cpu(udev->descriptor.field)); \
} \
static DEVICE_ATTR_RO(field)
usb_descriptor_attr_le16(idVendor, "%04x\n");
usb_descriptor_attr_le16(idProduct, "%04x\n");
usb_descriptor_attr_le16(bcdDevice, "%04x\n");
#define usb_descriptor_attr(field, format_string) \
static ssize_t \
field##_show(struct device *dev, struct device_attribute *attr, \
char *buf) \
{ \
struct usb_device *udev; \
\
udev = to_usb_device(dev); \
return sprintf(buf, format_string, udev->descriptor.field); \
} \
static DEVICE_ATTR_RO(field)
usb_descriptor_attr(bDeviceClass, "%02x\n");
usb_descriptor_attr(bDeviceSubClass, "%02x\n");
usb_descriptor_attr(bDeviceProtocol, "%02x\n");
usb_descriptor_attr(bNumConfigurations, "%d\n");
usb_descriptor_attr(bMaxPacketSize0, "%d\n");
/* show if the device is authorized (1) or not (0) */
static ssize_t authorized_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct usb_device *usb_dev = to_usb_device(dev);
return snprintf(buf, PAGE_SIZE, "%u\n", usb_dev->authorized);
}
/*
* Authorize a device to be used in the system
*
* Writing a 0 deauthorizes the device, writing a 1 authorizes it.
*/
static ssize_t authorized_store(struct device *dev,
struct device_attribute *attr, const char *buf,
size_t size)
{
ssize_t result;
struct usb_device *usb_dev = to_usb_device(dev);
unsigned val;
result = sscanf(buf, "%u\n", &val);
if (result != 1)
result = -EINVAL;
else if (val == 0)
result = usb_deauthorize_device(usb_dev);
else
result = usb_authorize_device(usb_dev);
return result < 0 ? result : size;
}
static DEVICE_ATTR_IGNORE_LOCKDEP(authorized, S_IRUGO | S_IWUSR,
authorized_show, authorized_store);
/* "Safely remove a device" */
static ssize_t remove_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct usb_device *udev = to_usb_device(dev);
int rc = 0;
usb_lock_device(udev);
if (udev->state != USB_STATE_NOTATTACHED) {
/* To avoid races, first unconfigure and then remove */
usb_set_configuration(udev, -1);
rc = usb_remove_device(udev);
}
if (rc == 0)
rc = count;
usb_unlock_device(udev);
return rc;
}
static DEVICE_ATTR_IGNORE_LOCKDEP(remove, S_IWUSR, NULL, remove_store);
static struct attribute *dev_attrs[] = {
/* current configuration's attributes */
&dev_attr_configuration.attr,
&dev_attr_bNumInterfaces.attr,
&dev_attr_bConfigurationValue.attr,
&dev_attr_bmAttributes.attr,
&dev_attr_bMaxPower.attr,
/* device attributes */
&dev_attr_urbnum.attr,
&dev_attr_idVendor.attr,
&dev_attr_idProduct.attr,
&dev_attr_bcdDevice.attr,
&dev_attr_bDeviceClass.attr,
&dev_attr_bDeviceSubClass.attr,
&dev_attr_bDeviceProtocol.attr,
&dev_attr_bNumConfigurations.attr,
&dev_attr_bMaxPacketSize0.attr,
&dev_attr_speed.attr,
&dev_attr_rx_lanes.attr,
&dev_attr_tx_lanes.attr,
&dev_attr_busnum.attr,
&dev_attr_devnum.attr,
&dev_attr_devpath.attr,
&dev_attr_version.attr,
&dev_attr_maxchild.attr,
&dev_attr_quirks.attr,
&dev_attr_avoid_reset_quirk.attr,
&dev_attr_authorized.attr,
&dev_attr_remove.attr,
&dev_attr_removable.attr,
&dev_attr_ltm_capable.attr,
#ifdef CONFIG_OF
&dev_attr_devspec.attr,
#endif
NULL,
};
static struct attribute_group dev_attr_grp = {
.attrs = dev_attrs,
};
/* When modifying this list, be sure to modify dev_string_attrs_are_visible()
* accordingly.
*/
static struct attribute *dev_string_attrs[] = {
&dev_attr_manufacturer.attr,
&dev_attr_product.attr,
&dev_attr_serial.attr,
NULL
};
static umode_t dev_string_attrs_are_visible(struct kobject *kobj,
struct attribute *a, int n)
{
struct device *dev = kobj_to_dev(kobj);
struct usb_device *udev = to_usb_device(dev);
if (a == &dev_attr_manufacturer.attr) {
if (udev->manufacturer == NULL)
return 0;
} else if (a == &dev_attr_product.attr) {
if (udev->product == NULL)
return 0;
} else if (a == &dev_attr_serial.attr) {
if (udev->serial == NULL)
return 0;
}
return a->mode;
}
static struct attribute_group dev_string_attr_grp = {
.attrs = dev_string_attrs,
.is_visible = dev_string_attrs_are_visible,
};
const struct attribute_group *usb_device_groups[] = {
&dev_attr_grp,
&dev_string_attr_grp,
NULL
};
/* Binary descriptors */
static ssize_t
read_descriptors(struct file *filp, struct kobject *kobj,
struct bin_attribute *attr,
char *buf, loff_t off, size_t count)
{
struct device *dev = kobj_to_dev(kobj);
struct usb_device *udev = to_usb_device(dev);
size_t nleft = count;
size_t srclen, n;
int cfgno;
void *src;
int retval;
retval = usb_lock_device_interruptible(udev);
if (retval < 0)
return -EINTR;
/* The binary attribute begins with the device descriptor.
* Following that are the raw descriptor entries for all the
* configurations (config plus subsidiary descriptors).
*/
for (cfgno = -1; cfgno < udev->descriptor.bNumConfigurations &&
nleft > 0; ++cfgno) {
if (cfgno < 0) {
src = &udev->descriptor;
srclen = sizeof(struct usb_device_descriptor);
} else {
src = udev->rawdescriptors[cfgno];
srclen = __le16_to_cpu(udev->config[cfgno].desc.
wTotalLength);
}
if (off < srclen) {
n = min(nleft, srclen - (size_t) off);
memcpy(buf, src + off, n);
nleft -= n;
buf += n;
off = 0;
} else {
off -= srclen;
}
}
usb_unlock_device(udev);
return count - nleft;
}
static struct bin_attribute dev_bin_attr_descriptors = {
.attr = {.name = "descriptors", .mode = 0444},
.read = read_descriptors,
.size = 18 + 65535, /* dev descr + max-size raw descriptor */
};
/*
* Show & store the current value of authorized_default
*/
static ssize_t authorized_default_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct usb_device *rh_usb_dev = to_usb_device(dev);
struct usb_bus *usb_bus = rh_usb_dev->bus;
struct usb_hcd *hcd;
hcd = bus_to_hcd(usb_bus);
return snprintf(buf, PAGE_SIZE, "%u\n", hcd->dev_policy);
}
static ssize_t authorized_default_store(struct device *dev,
struct device_attribute *attr,
const char *buf, size_t size)
{
ssize_t result;
unsigned int val;
struct usb_device *rh_usb_dev = to_usb_device(dev);
struct usb_bus *usb_bus = rh_usb_dev->bus;
struct usb_hcd *hcd;
hcd = bus_to_hcd(usb_bus);
result = sscanf(buf, "%u\n", &val);
if (result == 1) {
hcd->dev_policy = val <= USB_DEVICE_AUTHORIZE_INTERNAL ?
val : USB_DEVICE_AUTHORIZE_ALL;
result = size;
} else {
result = -EINVAL;
}
return result;
}
static DEVICE_ATTR_RW(authorized_default);
/*
* interface_authorized_default_show - show default authorization status
* for USB interfaces
*
* note: interface_authorized_default is the default value
* for initializing the authorized attribute of interfaces
*/
static ssize_t interface_authorized_default_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct usb_device *usb_dev = to_usb_device(dev);
struct usb_hcd *hcd = bus_to_hcd(usb_dev->bus);
return sprintf(buf, "%u\n", !!HCD_INTF_AUTHORIZED(hcd));
}
/*
* interface_authorized_default_store - store default authorization status
* for USB interfaces
*
* note: interface_authorized_default is the default value
* for initializing the authorized attribute of interfaces
*/
static ssize_t interface_authorized_default_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
struct usb_device *usb_dev = to_usb_device(dev);
struct usb_hcd *hcd = bus_to_hcd(usb_dev->bus);
int rc = count;
bool val;
if (strtobool(buf, &val) != 0)
return -EINVAL;
if (val)
set_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags);
else
clear_bit(HCD_FLAG_INTF_AUTHORIZED, &hcd->flags);
return rc;
}
static DEVICE_ATTR_RW(interface_authorized_default);
/* Group all the USB bus attributes */
static struct attribute *usb_bus_attrs[] = {
&dev_attr_authorized_default.attr,
&dev_attr_interface_authorized_default.attr,
NULL,
};
static const struct attribute_group usb_bus_attr_group = {
.name = NULL, /* we want them in the same directory */
.attrs = usb_bus_attrs,
};
static int add_default_authorized_attributes(struct device *dev)
{
int rc = 0;
if (is_usb_device(dev))
rc = sysfs_create_group(&dev->kobj, &usb_bus_attr_group);
return rc;
}
static void remove_default_authorized_attributes(struct device *dev)
{
if (is_usb_device(dev)) {
sysfs_remove_group(&dev->kobj, &usb_bus_attr_group);
}
}
int usb_create_sysfs_dev_files(struct usb_device *udev)
{
struct device *dev = &udev->dev;
int retval;
retval = device_create_bin_file(dev, &dev_bin_attr_descriptors);
if (retval)
goto error;
retval = add_persist_attributes(dev);
if (retval)
goto error;
retval = add_power_attributes(dev);
if (retval)
goto error;
if (is_root_hub(udev)) {
retval = add_default_authorized_attributes(dev);
if (retval)
goto error;
}
return retval;
error:
usb_remove_sysfs_dev_files(udev);
return retval;
}
void usb_remove_sysfs_dev_files(struct usb_device *udev)
{
struct device *dev = &udev->dev;
if (is_root_hub(udev))
remove_default_authorized_attributes(dev);
remove_power_attributes(dev);
remove_persist_attributes(dev);
device_remove_bin_file(dev, &dev_bin_attr_descriptors);
}
/* Interface Association Descriptor fields */
#define usb_intf_assoc_attr(field, format_string) \
static ssize_t \
iad_##field##_show(struct device *dev, struct device_attribute *attr, \
char *buf) \
{ \
struct usb_interface *intf = to_usb_interface(dev); \
\
return sprintf(buf, format_string, \
intf->intf_assoc->field); \
} \
static DEVICE_ATTR_RO(iad_##field)
usb_intf_assoc_attr(bFirstInterface, "%02x\n");
usb_intf_assoc_attr(bInterfaceCount, "%02d\n");
usb_intf_assoc_attr(bFunctionClass, "%02x\n");
usb_intf_assoc_attr(bFunctionSubClass, "%02x\n");
usb_intf_assoc_attr(bFunctionProtocol, "%02x\n");
/* Interface fields */
#define usb_intf_attr(field, format_string) \
static ssize_t \
field##_show(struct device *dev, struct device_attribute *attr, \
char *buf) \
{ \
struct usb_interface *intf = to_usb_interface(dev); \
\
return sprintf(buf, format_string, \
intf->cur_altsetting->desc.field); \
} \
static DEVICE_ATTR_RO(field)
usb_intf_attr(bInterfaceNumber, "%02x\n");
usb_intf_attr(bAlternateSetting, "%2d\n");
usb_intf_attr(bNumEndpoints, "%02x\n");
usb_intf_attr(bInterfaceClass, "%02x\n");
usb_intf_attr(bInterfaceSubClass, "%02x\n");
usb_intf_attr(bInterfaceProtocol, "%02x\n");
static ssize_t interface_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct usb_interface *intf;
char *string;
intf = to_usb_interface(dev);
string = READ_ONCE(intf->cur_altsetting->string);
if (!string)
return 0;
return sprintf(buf, "%s\n", string);
}
static DEVICE_ATTR_RO(interface);
static ssize_t modalias_show(struct device *dev, struct device_attribute *attr,
char *buf)
{
struct usb_interface *intf;
struct usb_device *udev;
struct usb_host_interface *alt;
intf = to_usb_interface(dev);
udev = interface_to_usbdev(intf);
alt = READ_ONCE(intf->cur_altsetting);
return sprintf(buf, "usb:v%04Xp%04Xd%04Xdc%02Xdsc%02Xdp%02X"
"ic%02Xisc%02Xip%02Xin%02X\n",
le16_to_cpu(udev->descriptor.idVendor),
le16_to_cpu(udev->descriptor.idProduct),
le16_to_cpu(udev->descriptor.bcdDevice),
udev->descriptor.bDeviceClass,
udev->descriptor.bDeviceSubClass,
udev->descriptor.bDeviceProtocol,
alt->desc.bInterfaceClass,
alt->desc.bInterfaceSubClass,
alt->desc.bInterfaceProtocol,
alt->desc.bInterfaceNumber);
}
static DEVICE_ATTR_RO(modalias);
static ssize_t supports_autosuspend_show(struct device *dev,
struct device_attribute *attr,
char *buf)
{
int s;
s = device_lock_interruptible(dev);
if (s < 0)
return -EINTR;
/* Devices will be autosuspended even when an interface isn't claimed */
s = (!dev->driver || to_usb_driver(dev->driver)->supports_autosuspend);
device_unlock(dev);
return sprintf(buf, "%u\n", s);
}
static DEVICE_ATTR_RO(supports_autosuspend);
/*
* interface_authorized_show - show authorization status of an USB interface
* 1 is authorized, 0 is deauthorized
*/
static ssize_t interface_authorized_show(struct device *dev,
struct device_attribute *attr, char *buf)
{
struct usb_interface *intf = to_usb_interface(dev);
return sprintf(buf, "%u\n", intf->authorized);
}
/*
* interface_authorized_store - authorize or deauthorize an USB interface
*/
static ssize_t interface_authorized_store(struct device *dev,
struct device_attribute *attr, const char *buf, size_t count)
{
struct usb_interface *intf = to_usb_interface(dev);
bool val;
if (strtobool(buf, &val) != 0)
return -EINVAL;
if (val)
usb_authorize_interface(intf);
else
usb_deauthorize_interface(intf);
return count;
}
static struct device_attribute dev_attr_interface_authorized =
__ATTR(authorized, S_IRUGO | S_IWUSR,
interface_authorized_show, interface_authorized_store);
static struct attribute *intf_attrs[] = {
&dev_attr_bInterfaceNumber.attr,
&dev_attr_bAlternateSetting.attr,
&dev_attr_bNumEndpoints.attr,
&dev_attr_bInterfaceClass.attr,
&dev_attr_bInterfaceSubClass.attr,
&dev_attr_bInterfaceProtocol.attr,
&dev_attr_modalias.attr,
&dev_attr_supports_autosuspend.attr,
&dev_attr_interface_authorized.attr,
NULL,
};
static struct attribute_group intf_attr_grp = {
.attrs = intf_attrs,
};
static struct attribute *intf_assoc_attrs[] = {
&dev_attr_iad_bFirstInterface.attr,
&dev_attr_iad_bInterfaceCount.attr,
&dev_attr_iad_bFunctionClass.attr,
&dev_attr_iad_bFunctionSubClass.attr,
&dev_attr_iad_bFunctionProtocol.attr,
NULL,
};
static umode_t intf_assoc_attrs_are_visible(struct kobject *kobj,
struct attribute *a, int n)
{
struct device *dev = kobj_to_dev(kobj);
struct usb_interface *intf = to_usb_interface(dev);
if (intf->intf_assoc == NULL)
return 0;
return a->mode;
}
static struct attribute_group intf_assoc_attr_grp = {
.attrs = intf_assoc_attrs,
.is_visible = intf_assoc_attrs_are_visible,
};
const struct attribute_group *usb_interface_groups[] = {
&intf_attr_grp,
&intf_assoc_attr_grp,
NULL
};
void usb_create_sysfs_intf_files(struct usb_interface *intf)
{
struct usb_device *udev = interface_to_usbdev(intf);
struct usb_host_interface *alt = intf->cur_altsetting;
if (intf->sysfs_files_created || intf->unregistering)
return;
if (!alt->string && !(udev->quirks & USB_QUIRK_CONFIG_INTF_STRINGS))
alt->string = usb_cache_string(udev, alt->desc.iInterface);
if (alt->string && device_create_file(&intf->dev, &dev_attr_interface)) {
/* This is not a serious error */
dev_dbg(&intf->dev, "interface string descriptor file not created\n");
}
intf->sysfs_files_created = 1;
}
void usb_remove_sysfs_intf_files(struct usb_interface *intf)
{
if (!intf->sysfs_files_created)
return;
device_remove_file(&intf->dev, &dev_attr_interface);
intf->sysfs_files_created = 0;
}