// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (C) 2003-2008 Takahiro Hirofuchi
* Copyright (C) 2015-2016 Nobuo Iwata
*/
#include <linux/kthread.h>
#include <linux/file.h>
#include <linux/net.h>
#include <linux/platform_device.h>
#include <linux/slab.h>
/* Hardening for Spectre-v1 */
#include <linux/nospec.h>
#include "usbip_common.h"
#include "vhci.h"
/* TODO: refine locking ?*/
/*
* output example:
* hub port sta spd dev sockfd local_busid
* hs 0000 004 000 00000000 000003 1-2.3
* ................................................
* ss 0008 004 000 00000000 000004 2-3.4
* ................................................
*
* Output includes socket fd instead of socket pointer address to avoid
* leaking kernel memory address in:
* /sys/devices/platform/vhci_hcd.0/status and in debug output.
* The socket pointer address is not used at the moment and it was made
* visible as a convenient way to find IP address from socket pointer
* address by looking up /proc/net/{tcp,tcp6}. As this opens a security
* hole, the change is made to use sockfd instead.
*
*/
static void port_show_vhci(char **out, int hub, int port, struct vhci_device *vdev)
{
if (hub == HUB_SPEED_HIGH)
*out += sprintf(*out, "hs %04u %03u ",
port, vdev->ud.status);
else /* hub == HUB_SPEED_SUPER */
*out += sprintf(*out, "ss %04u %03u ",
port, vdev->ud.status);
if (vdev->ud.status == VDEV_ST_USED) {
*out += sprintf(*out, "%03u %08x ",
vdev->speed, vdev->devid);
*out += sprintf(*out, "%06u %s",
vdev->ud.sockfd,
dev_name(&vdev->udev->dev));
} else {
*out += sprintf(*out, "000 00000000 ");
*out += sprintf(*out, "000000 0-0");
}
*out += sprintf(*out, "\n");
}
/* Sysfs entry to show port status */
static ssize_t status_show_vhci(int pdev_nr, char *out)
{
struct platform_device *pdev = vhcis[pdev_nr].pdev;
struct vhci *vhci;
struct usb_hcd *hcd;
struct vhci_hcd *vhci_hcd;
char *s = out;
int i;
unsigned long flags;
if (!pdev || !out) {
usbip_dbg_vhci_sysfs("show status error\n");
return 0;
}
hcd = platform_get_drvdata(pdev);
vhci_hcd = hcd_to_vhci_hcd(hcd);
vhci = vhci_hcd->vhci;
spin_lock_irqsave(&vhci->lock, flags);
for (i = 0; i < VHCI_HC_PORTS; i++) {
struct vhci_device *vdev = &vhci->vhci_hcd_hs->vdev[i];
spin_lock(&vdev->ud.lock);
port_show_vhci(&out, HUB_SPEED_HIGH,
pdev_nr * VHCI_PORTS + i, vdev);
spin_unlock(&vdev->ud.lock);
}
for (i = 0; i < VHCI_HC_PORTS; i++) {
struct vhci_device *vdev = &vhci->vhci_hcd_ss->vdev[i];
spin_lock(&vdev->ud.lock);
port_show_vhci(&out, HUB_SPEED_SUPER,
pdev_nr * VHCI_PORTS + VHCI_HC_PORTS + i, vdev);
spin_unlock(&vdev->ud.lock);
}
spin_unlock_irqrestore(&vhci->lock, flags);
return out - s;
}
static ssize_t status_show_not_ready(int pdev_nr, char *out)
{
char *s = out;
int i = 0;
for (i = 0; i < VHCI_HC_PORTS; i++) {
out += sprintf(out, "hs %04u %03u ",
(pdev_nr * VHCI_PORTS) + i,
VDEV_ST_NOTASSIGNED);
out += sprintf(out, "000 00000000 0000000000000000 0-0");
out += sprintf(out, "\n");
}
for (i = 0; i < VHCI_HC_PORTS; i++) {
out += sprintf(out, "ss %04u %03u ",
(pdev_nr * VHCI_PORTS) + VHCI_HC_PORTS + i,
VDEV_ST_NOTASSIGNED);
out += sprintf(out, "000 00000000 0000000000000000 0-0");
out += sprintf(out, "\n");
}
return out - s;
}
static int status_name_to_id(const char *name)
{
char *c;
long val;
int ret;
c = strchr(name, '.');
if (c == NULL)
return 0;
ret = kstrtol(c+1, 10, &val);
if (ret < 0)
return ret;
return val;
}
static ssize_t status_show(struct device *dev,
struct device_attribute *attr, char *out)
{
char *s = out;
int pdev_nr;
out += sprintf(out,
"hub port sta spd dev sockfd local_busid\n");
pdev_nr = status_name_to_id(attr->attr.name);
if (pdev_nr < 0)
out += status_show_not_ready(pdev_nr, out);
else
out += status_show_vhci(pdev_nr, out);
return out - s;
}
static ssize_t nports_show(struct device *dev, struct device_attribute *attr,
char *out)
{
char *s = out;
/*
* Half the ports are for SPEED_HIGH and half for SPEED_SUPER,
* thus the * 2.
*/
out += sprintf(out, "%d\n", VHCI_PORTS * vhci_num_controllers);
return out - s;
}
static DEVICE_ATTR_RO(nports);
/* Sysfs entry to shutdown a virtual connection */
static int vhci_port_disconnect(struct vhci_hcd *vhci_hcd, __u32 rhport)
{
struct vhci_device *vdev = &vhci_hcd->vdev[rhport];
struct vhci *vhci = vhci_hcd->vhci;
unsigned long flags;
usbip_dbg_vhci_sysfs("enter\n");
mutex_lock(&vdev->ud.sysfs_lock);
/* lock */
spin_lock_irqsave(&vhci->lock, flags);
spin_lock(&vdev->ud.lock);
if (vdev->ud.status == VDEV_ST_NULL) {
pr_err("not connected %d\n", vdev->ud.status);
/* unlock */
spin_unlock(&vdev->ud.lock);
spin_unlock_irqrestore(&vhci->lock, flags);
mutex_unlock(&vdev->ud.sysfs_lock);
return -EINVAL;
}
/* unlock */
spin_unlock(&vdev->ud.lock);
spin_unlock_irqrestore(&vhci->lock, flags);
usbip_event_add(&vdev->ud, VDEV_EVENT_DOWN);
mutex_unlock(&vdev->ud.sysfs_lock);
return 0;
}
static int valid_port(__u32 *pdev_nr, __u32 *rhport)
{
if (*pdev_nr >= vhci_num_controllers) {
pr_err("pdev %u\n", *pdev_nr);
return 0;
}
*pdev_nr = array_index_nospec(*pdev_nr, vhci_num_controllers);
if (*rhport >= VHCI_HC_PORTS) {
pr_err("rhport %u\n", *rhport);
return 0;
}
*rhport = array_index_nospec(*rhport, VHCI_HC_PORTS);
return 1;
}
static ssize_t detach_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
__u32 port = 0, pdev_nr = 0, rhport = 0;
struct usb_hcd *hcd;
struct vhci_hcd *vhci_hcd;
int ret;
if (kstrtoint(buf, 10, &port) < 0)
return -EINVAL;
pdev_nr = port_to_pdev_nr(port);
rhport = port_to_rhport(port);
if (!valid_port(&pdev_nr, &rhport))
return -EINVAL;
hcd = platform_get_drvdata(vhcis[pdev_nr].pdev);
if (hcd == NULL) {
dev_err(dev, "port is not ready %u\n", port);
return -EAGAIN;
}
usbip_dbg_vhci_sysfs("rhport %d\n", rhport);
if ((port / VHCI_HC_PORTS) % 2)
vhci_hcd = hcd_to_vhci_hcd(hcd)->vhci->vhci_hcd_ss;
else
vhci_hcd = hcd_to_vhci_hcd(hcd)->vhci->vhci_hcd_hs;
ret = vhci_port_disconnect(vhci_hcd, rhport);
if (ret < 0)
return -EINVAL;
usbip_dbg_vhci_sysfs("Leave\n");
return count;
}
static DEVICE_ATTR_WO(detach);
static int valid_args(__u32 *pdev_nr, __u32 *rhport,
enum usb_device_speed speed)
{
if (!valid_port(pdev_nr, rhport)) {
return 0;
}
switch (speed) {
case USB_SPEED_LOW:
case USB_SPEED_FULL:
case USB_SPEED_HIGH:
case USB_SPEED_WIRELESS:
case USB_SPEED_SUPER:
case USB_SPEED_SUPER_PLUS:
break;
default:
pr_err("Failed attach request for unsupported USB speed: %s\n",
usb_speed_string(speed));
return 0;
}
return 1;
}
/* Sysfs entry to establish a virtual connection */
/*
* To start a new USB/IP attachment, a userland program needs to setup a TCP
* connection and then write its socket descriptor with remote device
* information into this sysfs file.
*
* A remote device is virtually attached to the root-hub port of @rhport with
* @speed. @devid is embedded into a request to specify the remote device in a
* server host.
*
* write() returns 0 on success, else negative errno.
*/
static ssize_t attach_store(struct device *dev, struct device_attribute *attr,
const char *buf, size_t count)
{
struct socket *socket;
int sockfd = 0;
__u32 port = 0, pdev_nr = 0, rhport = 0, devid = 0, speed = 0;
struct usb_hcd *hcd;
struct vhci_hcd *vhci_hcd;
struct vhci_device *vdev;
struct vhci *vhci;
int err;
unsigned long flags;
struct task_struct *tcp_rx = NULL;
struct task_struct *tcp_tx = NULL;
/*
* @rhport: port number of vhci_hcd
* @sockfd: socket descriptor of an established TCP connection
* @devid: unique device identifier in a remote host
* @speed: usb device speed in a remote host
*/
if (sscanf(buf, "%u %u %u %u", &port, &sockfd, &devid, &speed) != 4)
return -EINVAL;
pdev_nr = port_to_pdev_nr(port);
rhport = port_to_rhport(port);
usbip_dbg_vhci_sysfs("port(%u) pdev(%d) rhport(%u)\n",
port, pdev_nr, rhport);
usbip_dbg_vhci_sysfs("sockfd(%u) devid(%u) speed(%u)\n",
sockfd, devid, speed);
/* check received parameters */
if (!valid_args(&pdev_nr, &rhport, speed))
return -EINVAL;
hcd = platform_get_drvdata(vhcis[pdev_nr].pdev);
if (hcd == NULL) {
dev_err(dev, "port %d is not ready\n", port);
return -EAGAIN;
}
vhci_hcd = hcd_to_vhci_hcd(hcd);
vhci = vhci_hcd->vhci;
if (speed >= USB_SPEED_SUPER)
vdev = &vhci->vhci_hcd_ss->vdev[rhport];
else
vdev = &vhci->vhci_hcd_hs->vdev[rhport];
mutex_lock(&vdev->ud.sysfs_lock);
/* Extract socket from fd. */
socket = sockfd_lookup(sockfd, &err);
if (!socket) {
dev_err(dev, "failed to lookup sock");
err = -EINVAL;
goto unlock_mutex;
}
if (socket->type != SOCK_STREAM) {
dev_err(dev, "Expecting SOCK_STREAM - found %d",
socket->type);
sockfd_put(socket);
err = -EINVAL;
goto unlock_mutex;
}
/* create threads before locking */
tcp_rx = kthread_create(vhci_rx_loop, &vdev->ud, "vhci_rx");
if (IS_ERR(tcp_rx)) {
sockfd_put(socket);
err = -EINVAL;
goto unlock_mutex;
}
tcp_tx = kthread_create(vhci_tx_loop, &vdev->ud, "vhci_tx");
if (IS_ERR(tcp_tx)) {
kthread_stop(tcp_rx);
sockfd_put(socket);
err = -EINVAL;
goto unlock_mutex;
}
/* get task structs now */
get_task_struct(tcp_rx);
get_task_struct(tcp_tx);
/* now begin lock until setting vdev status set */
spin_lock_irqsave(&vhci->lock, flags);
spin_lock(&vdev->ud.lock);
if (vdev->ud.status != VDEV_ST_NULL) {
/* end of the lock */
spin_unlock(&vdev->ud.lock);
spin_unlock_irqrestore(&vhci->lock, flags);
sockfd_put(socket);
kthread_stop_put(tcp_rx);
kthread_stop_put(tcp_tx);
dev_err(dev, "port %d already used\n", rhport);
/*
* Will be retried from userspace
* if there's another free port.
*/
err = -EBUSY;
goto unlock_mutex;
}
dev_info(dev, "pdev(%u) rhport(%u) sockfd(%d)\n",
pdev_nr, rhport, sockfd);
dev_info(dev, "devid(%u) speed(%u) speed_str(%s)\n",
devid, speed, usb_speed_string(speed));
vdev->devid = devid;
vdev->speed = speed;
vdev->ud.sockfd = sockfd;
vdev->ud.tcp_socket = socket;
vdev->ud.tcp_rx = tcp_rx;
vdev->ud.tcp_tx = tcp_tx;
vdev->ud.status = VDEV_ST_NOTASSIGNED;
usbip_kcov_handle_init(&vdev->ud);
spin_unlock(&vdev->ud.lock);
spin_unlock_irqrestore(&vhci->lock, flags);
/* end the lock */
wake_up_process(vdev->ud.tcp_rx);
wake_up_process(vdev->ud.tcp_tx);
rh_port_connect(vdev, speed);
dev_info(dev, "Device attached\n");
mutex_unlock(&vdev->ud.sysfs_lock);
return count;
unlock_mutex:
mutex_unlock(&vdev->ud.sysfs_lock);
return err;
}
static DEVICE_ATTR_WO(attach);
#define MAX_STATUS_NAME 16
struct status_attr {
struct device_attribute attr;
char name[MAX_STATUS_NAME+1];
};
static struct status_attr *status_attrs;
static void set_status_attr(int id)
{
struct status_attr *status;
status = status_attrs + id;
if (id == 0)
strcpy(status->name, "status");
else
snprintf(status->name, MAX_STATUS_NAME+1, "status.%d", id);
status->attr.attr.name = status->name;
status->attr.attr.mode = S_IRUGO;
status->attr.show = status_show;
sysfs_attr_init(&status->attr.attr);
}
static int init_status_attrs(void)
{
int id;
status_attrs = kcalloc(vhci_num_controllers, sizeof(struct status_attr),
GFP_KERNEL);
if (status_attrs == NULL)
return -ENOMEM;
for (id = 0; id < vhci_num_controllers; id++)
set_status_attr(id);
return 0;
}
static void finish_status_attrs(void)
{
kfree(status_attrs);
}
struct attribute_group vhci_attr_group = {
.attrs = NULL,
};
int vhci_init_attr_group(void)
{
struct attribute **attrs;
int ret, i;
attrs = kcalloc((vhci_num_controllers + 5), sizeof(struct attribute *),
GFP_KERNEL);
if (attrs == NULL)
return -ENOMEM;
ret = init_status_attrs();
if (ret) {
kfree(attrs);
return ret;
}
*attrs = &dev_attr_nports.attr;
*(attrs + 1) = &dev_attr_detach.attr;
*(attrs + 2) = &dev_attr_attach.attr;
*(attrs + 3) = &dev_attr_usbip_debug.attr;
for (i = 0; i < vhci_num_controllers; i++)
*(attrs + i + 4) = &((status_attrs + i)->attr.attr);
vhci_attr_group.attrs = attrs;
return 0;
}
void vhci_finish_attr_group(void)
{
finish_status_attrs();
kfree(vhci_attr_group.attrs);
}
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