1 // SPDX-License-Identifier: GPL-2.0+
2 /*
3 * Copyright (C) 2003-2008 Takahiro Hirofuchi
4 * Copyright (C) 2015-2016 Nobuo Iwata
5 */
6
7 #include <linux/kthread.h>
8 #include <linux/file.h>
9 #include <linux/net.h>
10 #include <linux/platform_device.h>
11 #include <linux/slab.h>
12
13 /* Hardening for Spectre-v1 */
14 #include <linux/nospec.h>
15
16 #include "usbip_common.h"
17 #include "vhci.h"
18
19 /* TODO: refine locking ?*/
20
21 /*
22 * output example:
23 * hub port sta spd dev sockfd local_busid
24 * hs 0000 004 000 00000000 000003 1-2.3
25 * ................................................
26 * ss 0008 004 000 00000000 000004 2-3.4
27 * ................................................
28 *
29 * Output includes socket fd instead of socket pointer address to avoid
30 * leaking kernel memory address in:
31 * /sys/devices/platform/vhci_hcd.0/status and in debug output.
32 * The socket pointer address is not used at the moment and it was made
33 * visible as a convenient way to find IP address from socket pointer
34 * address by looking up /proc/net/{tcp,tcp6}. As this opens a security
35 * hole, the change is made to use sockfd instead.
36 *
37 */
port_show_vhci(char ** out,int hub,int port,struct vhci_device * vdev)38 static void port_show_vhci(char **out, int hub, int port, struct vhci_device *vdev)
39 {
40 if (hub == HUB_SPEED_HIGH)
41 *out += sprintf(*out, "hs %04u %03u ",
42 port, vdev->ud.status);
43 else /* hub == HUB_SPEED_SUPER */
44 *out += sprintf(*out, "ss %04u %03u ",
45 port, vdev->ud.status);
46
47 if (vdev->ud.status == VDEV_ST_USED) {
48 *out += sprintf(*out, "%03u %08x ",
49 vdev->speed, vdev->devid);
50 *out += sprintf(*out, "%06u %s",
51 vdev->ud.sockfd,
52 dev_name(&vdev->udev->dev));
53
54 } else {
55 *out += sprintf(*out, "000 00000000 ");
56 *out += sprintf(*out, "000000 0-0");
57 }
58
59 *out += sprintf(*out, "\n");
60 }
61
62 /* Sysfs entry to show port status */
status_show_vhci(int pdev_nr,char * out)63 static ssize_t status_show_vhci(int pdev_nr, char *out)
64 {
65 struct platform_device *pdev = vhcis[pdev_nr].pdev;
66 struct vhci *vhci;
67 struct usb_hcd *hcd;
68 struct vhci_hcd *vhci_hcd;
69 char *s = out;
70 int i;
71 unsigned long flags;
72
73 if (!pdev || !out) {
74 usbip_dbg_vhci_sysfs("show status error\n");
75 return 0;
76 }
77
78 hcd = platform_get_drvdata(pdev);
79 vhci_hcd = hcd_to_vhci_hcd(hcd);
80 vhci = vhci_hcd->vhci;
81
82 spin_lock_irqsave(&vhci->lock, flags);
83
84 for (i = 0; i < VHCI_HC_PORTS; i++) {
85 struct vhci_device *vdev = &vhci->vhci_hcd_hs->vdev[i];
86
87 spin_lock(&vdev->ud.lock);
88 port_show_vhci(&out, HUB_SPEED_HIGH,
89 pdev_nr * VHCI_PORTS + i, vdev);
90 spin_unlock(&vdev->ud.lock);
91 }
92
93 for (i = 0; i < VHCI_HC_PORTS; i++) {
94 struct vhci_device *vdev = &vhci->vhci_hcd_ss->vdev[i];
95
96 spin_lock(&vdev->ud.lock);
97 port_show_vhci(&out, HUB_SPEED_SUPER,
98 pdev_nr * VHCI_PORTS + VHCI_HC_PORTS + i, vdev);
99 spin_unlock(&vdev->ud.lock);
100 }
101
102 spin_unlock_irqrestore(&vhci->lock, flags);
103
104 return out - s;
105 }
106
status_show_not_ready(int pdev_nr,char * out)107 static ssize_t status_show_not_ready(int pdev_nr, char *out)
108 {
109 char *s = out;
110 int i = 0;
111
112 for (i = 0; i < VHCI_HC_PORTS; i++) {
113 out += sprintf(out, "hs %04u %03u ",
114 (pdev_nr * VHCI_PORTS) + i,
115 VDEV_ST_NOTASSIGNED);
116 out += sprintf(out, "000 00000000 0000000000000000 0-0");
117 out += sprintf(out, "\n");
118 }
119
120 for (i = 0; i < VHCI_HC_PORTS; i++) {
121 out += sprintf(out, "ss %04u %03u ",
122 (pdev_nr * VHCI_PORTS) + VHCI_HC_PORTS + i,
123 VDEV_ST_NOTASSIGNED);
124 out += sprintf(out, "000 00000000 0000000000000000 0-0");
125 out += sprintf(out, "\n");
126 }
127 return out - s;
128 }
129
status_name_to_id(const char * name)130 static int status_name_to_id(const char *name)
131 {
132 char *c;
133 long val;
134 int ret;
135
136 c = strchr(name, '.');
137 if (c == NULL)
138 return 0;
139
140 ret = kstrtol(c+1, 10, &val);
141 if (ret < 0)
142 return ret;
143
144 return val;
145 }
146
status_show(struct device * dev,struct device_attribute * attr,char * out)147 static ssize_t status_show(struct device *dev,
148 struct device_attribute *attr, char *out)
149 {
150 char *s = out;
151 int pdev_nr;
152
153 out += sprintf(out,
154 "hub port sta spd dev sockfd local_busid\n");
155
156 pdev_nr = status_name_to_id(attr->attr.name);
157 if (pdev_nr < 0)
158 out += status_show_not_ready(pdev_nr, out);
159 else
160 out += status_show_vhci(pdev_nr, out);
161
162 return out - s;
163 }
164
nports_show(struct device * dev,struct device_attribute * attr,char * out)165 static ssize_t nports_show(struct device *dev, struct device_attribute *attr,
166 char *out)
167 {
168 char *s = out;
169
170 /*
171 * Half the ports are for SPEED_HIGH and half for SPEED_SUPER,
172 * thus the * 2.
173 */
174 out += sprintf(out, "%d\n", VHCI_PORTS * vhci_num_controllers);
175 return out - s;
176 }
177 static DEVICE_ATTR_RO(nports);
178
179 /* Sysfs entry to shutdown a virtual connection */
vhci_port_disconnect(struct vhci_hcd * vhci_hcd,__u32 rhport)180 static int vhci_port_disconnect(struct vhci_hcd *vhci_hcd, __u32 rhport)
181 {
182 struct vhci_device *vdev = &vhci_hcd->vdev[rhport];
183 struct vhci *vhci = vhci_hcd->vhci;
184 unsigned long flags;
185
186 usbip_dbg_vhci_sysfs("enter\n");
187
188 /* lock */
189 spin_lock_irqsave(&vhci->lock, flags);
190 spin_lock(&vdev->ud.lock);
191
192 if (vdev->ud.status == VDEV_ST_NULL) {
193 pr_err("not connected %d\n", vdev->ud.status);
194
195 /* unlock */
196 spin_unlock(&vdev->ud.lock);
197 spin_unlock_irqrestore(&vhci->lock, flags);
198
199 return -EINVAL;
200 }
201
202 /* unlock */
203 spin_unlock(&vdev->ud.lock);
204 spin_unlock_irqrestore(&vhci->lock, flags);
205
206 usbip_event_add(&vdev->ud, VDEV_EVENT_DOWN);
207
208 return 0;
209 }
210
valid_port(__u32 * pdev_nr,__u32 * rhport)211 static int valid_port(__u32 *pdev_nr, __u32 *rhport)
212 {
213 if (*pdev_nr >= vhci_num_controllers) {
214 pr_err("pdev %u\n", *pdev_nr);
215 return 0;
216 }
217 *pdev_nr = array_index_nospec(*pdev_nr, vhci_num_controllers);
218
219 if (*rhport >= VHCI_HC_PORTS) {
220 pr_err("rhport %u\n", *rhport);
221 return 0;
222 }
223 *rhport = array_index_nospec(*rhport, VHCI_HC_PORTS);
224
225 return 1;
226 }
227
detach_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)228 static ssize_t detach_store(struct device *dev, struct device_attribute *attr,
229 const char *buf, size_t count)
230 {
231 __u32 port = 0, pdev_nr = 0, rhport = 0;
232 struct usb_hcd *hcd;
233 struct vhci_hcd *vhci_hcd;
234 int ret;
235
236 if (kstrtoint(buf, 10, &port) < 0)
237 return -EINVAL;
238
239 pdev_nr = port_to_pdev_nr(port);
240 rhport = port_to_rhport(port);
241
242 if (!valid_port(&pdev_nr, &rhport))
243 return -EINVAL;
244
245 hcd = platform_get_drvdata(vhcis[pdev_nr].pdev);
246 if (hcd == NULL) {
247 dev_err(dev, "port is not ready %u\n", port);
248 return -EAGAIN;
249 }
250
251 usbip_dbg_vhci_sysfs("rhport %d\n", rhport);
252
253 if ((port / VHCI_HC_PORTS) % 2)
254 vhci_hcd = hcd_to_vhci_hcd(hcd)->vhci->vhci_hcd_ss;
255 else
256 vhci_hcd = hcd_to_vhci_hcd(hcd)->vhci->vhci_hcd_hs;
257
258 ret = vhci_port_disconnect(vhci_hcd, rhport);
259 if (ret < 0)
260 return -EINVAL;
261
262 usbip_dbg_vhci_sysfs("Leave\n");
263
264 return count;
265 }
266 static DEVICE_ATTR_WO(detach);
267
valid_args(__u32 * pdev_nr,__u32 * rhport,enum usb_device_speed speed)268 static int valid_args(__u32 *pdev_nr, __u32 *rhport,
269 enum usb_device_speed speed)
270 {
271 if (!valid_port(pdev_nr, rhport)) {
272 return 0;
273 }
274
275 switch (speed) {
276 case USB_SPEED_LOW:
277 case USB_SPEED_FULL:
278 case USB_SPEED_HIGH:
279 case USB_SPEED_WIRELESS:
280 case USB_SPEED_SUPER:
281 break;
282 default:
283 pr_err("Failed attach request for unsupported USB speed: %s\n",
284 usb_speed_string(speed));
285 return 0;
286 }
287
288 return 1;
289 }
290
291 /* Sysfs entry to establish a virtual connection */
292 /*
293 * To start a new USB/IP attachment, a userland program needs to setup a TCP
294 * connection and then write its socket descriptor with remote device
295 * information into this sysfs file.
296 *
297 * A remote device is virtually attached to the root-hub port of @rhport with
298 * @speed. @devid is embedded into a request to specify the remote device in a
299 * server host.
300 *
301 * write() returns 0 on success, else negative errno.
302 */
attach_store(struct device * dev,struct device_attribute * attr,const char * buf,size_t count)303 static ssize_t attach_store(struct device *dev, struct device_attribute *attr,
304 const char *buf, size_t count)
305 {
306 struct socket *socket;
307 int sockfd = 0;
308 __u32 port = 0, pdev_nr = 0, rhport = 0, devid = 0, speed = 0;
309 struct usb_hcd *hcd;
310 struct vhci_hcd *vhci_hcd;
311 struct vhci_device *vdev;
312 struct vhci *vhci;
313 int err;
314 unsigned long flags;
315
316 /*
317 * @rhport: port number of vhci_hcd
318 * @sockfd: socket descriptor of an established TCP connection
319 * @devid: unique device identifier in a remote host
320 * @speed: usb device speed in a remote host
321 */
322 if (sscanf(buf, "%u %u %u %u", &port, &sockfd, &devid, &speed) != 4)
323 return -EINVAL;
324 pdev_nr = port_to_pdev_nr(port);
325 rhport = port_to_rhport(port);
326
327 usbip_dbg_vhci_sysfs("port(%u) pdev(%d) rhport(%u)\n",
328 port, pdev_nr, rhport);
329 usbip_dbg_vhci_sysfs("sockfd(%u) devid(%u) speed(%u)\n",
330 sockfd, devid, speed);
331
332 /* check received parameters */
333 if (!valid_args(&pdev_nr, &rhport, speed))
334 return -EINVAL;
335
336 hcd = platform_get_drvdata(vhcis[pdev_nr].pdev);
337 if (hcd == NULL) {
338 dev_err(dev, "port %d is not ready\n", port);
339 return -EAGAIN;
340 }
341
342 vhci_hcd = hcd_to_vhci_hcd(hcd);
343 vhci = vhci_hcd->vhci;
344
345 if (speed == USB_SPEED_SUPER)
346 vdev = &vhci->vhci_hcd_ss->vdev[rhport];
347 else
348 vdev = &vhci->vhci_hcd_hs->vdev[rhport];
349
350 /* Extract socket from fd. */
351 socket = sockfd_lookup(sockfd, &err);
352 if (!socket)
353 return -EINVAL;
354
355 /* now need lock until setting vdev status as used */
356
357 /* begin a lock */
358 spin_lock_irqsave(&vhci->lock, flags);
359 spin_lock(&vdev->ud.lock);
360
361 if (vdev->ud.status != VDEV_ST_NULL) {
362 /* end of the lock */
363 spin_unlock(&vdev->ud.lock);
364 spin_unlock_irqrestore(&vhci->lock, flags);
365
366 sockfd_put(socket);
367
368 dev_err(dev, "port %d already used\n", rhport);
369 /*
370 * Will be retried from userspace
371 * if there's another free port.
372 */
373 return -EBUSY;
374 }
375
376 dev_info(dev, "pdev(%u) rhport(%u) sockfd(%d)\n",
377 pdev_nr, rhport, sockfd);
378 dev_info(dev, "devid(%u) speed(%u) speed_str(%s)\n",
379 devid, speed, usb_speed_string(speed));
380
381 vdev->devid = devid;
382 vdev->speed = speed;
383 vdev->ud.sockfd = sockfd;
384 vdev->ud.tcp_socket = socket;
385 vdev->ud.status = VDEV_ST_NOTASSIGNED;
386
387 spin_unlock(&vdev->ud.lock);
388 spin_unlock_irqrestore(&vhci->lock, flags);
389 /* end the lock */
390
391 vdev->ud.tcp_rx = kthread_get_run(vhci_rx_loop, &vdev->ud, "vhci_rx");
392 vdev->ud.tcp_tx = kthread_get_run(vhci_tx_loop, &vdev->ud, "vhci_tx");
393
394 rh_port_connect(vdev, speed);
395
396 return count;
397 }
398 static DEVICE_ATTR_WO(attach);
399
400 #define MAX_STATUS_NAME 16
401
402 struct status_attr {
403 struct device_attribute attr;
404 char name[MAX_STATUS_NAME+1];
405 };
406
407 static struct status_attr *status_attrs;
408
set_status_attr(int id)409 static void set_status_attr(int id)
410 {
411 struct status_attr *status;
412
413 status = status_attrs + id;
414 if (id == 0)
415 strcpy(status->name, "status");
416 else
417 snprintf(status->name, MAX_STATUS_NAME+1, "status.%d", id);
418 status->attr.attr.name = status->name;
419 status->attr.attr.mode = S_IRUGO;
420 status->attr.show = status_show;
421 sysfs_attr_init(&status->attr.attr);
422 }
423
init_status_attrs(void)424 static int init_status_attrs(void)
425 {
426 int id;
427
428 status_attrs = kcalloc(vhci_num_controllers, sizeof(struct status_attr),
429 GFP_KERNEL);
430 if (status_attrs == NULL)
431 return -ENOMEM;
432
433 for (id = 0; id < vhci_num_controllers; id++)
434 set_status_attr(id);
435
436 return 0;
437 }
438
finish_status_attrs(void)439 static void finish_status_attrs(void)
440 {
441 kfree(status_attrs);
442 }
443
444 struct attribute_group vhci_attr_group = {
445 .attrs = NULL,
446 };
447
vhci_init_attr_group(void)448 int vhci_init_attr_group(void)
449 {
450 struct attribute **attrs;
451 int ret, i;
452
453 attrs = kcalloc((vhci_num_controllers + 5), sizeof(struct attribute *),
454 GFP_KERNEL);
455 if (attrs == NULL)
456 return -ENOMEM;
457
458 ret = init_status_attrs();
459 if (ret) {
460 kfree(attrs);
461 return ret;
462 }
463 *attrs = &dev_attr_nports.attr;
464 *(attrs + 1) = &dev_attr_detach.attr;
465 *(attrs + 2) = &dev_attr_attach.attr;
466 *(attrs + 3) = &dev_attr_usbip_debug.attr;
467 for (i = 0; i < vhci_num_controllers; i++)
468 *(attrs + i + 4) = &((status_attrs + i)->attr.attr);
469 vhci_attr_group.attrs = attrs;
470 return 0;
471 }
472
vhci_finish_attr_group(void)473 void vhci_finish_attr_group(void)
474 {
475 finish_status_attrs();
476 kfree(vhci_attr_group.attrs);
477 }
478
