1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (c) 2001 Paul Stewart
4 * Copyright (c) 2001 Vojtech Pavlik
5 *
6 * HID char devices, giving access to raw HID device events.
7 */
8
9/*
10 *
11 * Should you need to contact me, the author, you can do so either by
12 * e-mail - mail your message to Paul Stewart <stewart@wetlogic.net>
13 */
14
15#include <linux/poll.h>
16#include <linux/slab.h>
17#include <linux/sched/signal.h>
18#include <linux/module.h>
19#include <linux/init.h>
20#include <linux/input.h>
21#include <linux/usb.h>
22#include <linux/hid.h>
23#include <linux/hiddev.h>
24#include <linux/compat.h>
25#include <linux/vmalloc.h>
26#include <linux/nospec.h>
27#include "usbhid.h"
28
29#ifdef CONFIG_USB_DYNAMIC_MINORS
30#define HIDDEV_MINOR_BASE 0
31#define HIDDEV_MINORS 256
32#else
33#define HIDDEV_MINOR_BASE 96
34#define HIDDEV_MINORS 16
35#endif
36#define HIDDEV_BUFFER_SIZE 2048
37
38struct hiddev_list {
39 struct hiddev_usage_ref buffer[HIDDEV_BUFFER_SIZE];
40 int head;
41 int tail;
42 unsigned flags;
43 struct fasync_struct *fasync;
44 struct hiddev *hiddev;
45 struct list_head node;
46 struct mutex thread_lock;
47};
48
49/*
50 * Find a report, given the report's type and ID. The ID can be specified
51 * indirectly by REPORT_ID_FIRST (which returns the first report of the given
52 * type) or by (REPORT_ID_NEXT | old_id), which returns the next report of the
53 * given type which follows old_id.
54 */
55static struct hid_report *
56hiddev_lookup_report(struct hid_device *hid, struct hiddev_report_info *rinfo)
57{
58 unsigned int flags = rinfo->report_id & ~HID_REPORT_ID_MASK;
59 unsigned int rid = rinfo->report_id & HID_REPORT_ID_MASK;
60 struct hid_report_enum *report_enum;
61 struct hid_report *report;
62 struct list_head *list;
63
64 if (rinfo->report_type < HID_REPORT_TYPE_MIN ||
65 rinfo->report_type > HID_REPORT_TYPE_MAX)
66 return NULL;
67
68 report_enum = hid->report_enum +
69 (rinfo->report_type - HID_REPORT_TYPE_MIN);
70
71 switch (flags) {
72 case 0: /* Nothing to do -- report_id is already set correctly */
73 break;
74
75 case HID_REPORT_ID_FIRST:
76 if (list_empty(head: &report_enum->report_list))
77 return NULL;
78
79 list = report_enum->report_list.next;
80 report = list_entry(list, struct hid_report, list);
81 rinfo->report_id = report->id;
82 break;
83
84 case HID_REPORT_ID_NEXT:
85 report = report_enum->report_id_hash[rid];
86 if (!report)
87 return NULL;
88
89 list = report->list.next;
90 if (list == &report_enum->report_list)
91 return NULL;
92
93 report = list_entry(list, struct hid_report, list);
94 rinfo->report_id = report->id;
95 break;
96
97 default:
98 return NULL;
99 }
100
101 return report_enum->report_id_hash[rinfo->report_id];
102}
103
104/*
105 * Perform an exhaustive search of the report table for a usage, given its
106 * type and usage id.
107 */
108static struct hid_field *
109hiddev_lookup_usage(struct hid_device *hid, struct hiddev_usage_ref *uref)
110{
111 int i, j;
112 struct hid_report *report;
113 struct hid_report_enum *report_enum;
114 struct hid_field *field;
115
116 if (uref->report_type < HID_REPORT_TYPE_MIN ||
117 uref->report_type > HID_REPORT_TYPE_MAX)
118 return NULL;
119
120 report_enum = hid->report_enum +
121 (uref->report_type - HID_REPORT_TYPE_MIN);
122
123 list_for_each_entry(report, &report_enum->report_list, list) {
124 for (i = 0; i < report->maxfield; i++) {
125 field = report->field[i];
126 for (j = 0; j < field->maxusage; j++) {
127 if (field->usage[j].hid == uref->usage_code) {
128 uref->report_id = report->id;
129 uref->field_index = i;
130 uref->usage_index = j;
131 return field;
132 }
133 }
134 }
135 }
136
137 return NULL;
138}
139
140static void hiddev_send_event(struct hid_device *hid,
141 struct hiddev_usage_ref *uref)
142{
143 struct hiddev *hiddev = hid->hiddev;
144 struct hiddev_list *list;
145 unsigned long flags;
146
147 spin_lock_irqsave(&hiddev->list_lock, flags);
148 list_for_each_entry(list, &hiddev->list, node) {
149 if (uref->field_index != HID_FIELD_INDEX_NONE ||
150 (list->flags & HIDDEV_FLAG_REPORT) != 0) {
151 list->buffer[list->head] = *uref;
152 list->head = (list->head + 1) &
153 (HIDDEV_BUFFER_SIZE - 1);
154 kill_fasync(&list->fasync, SIGIO, POLL_IN);
155 }
156 }
157 spin_unlock_irqrestore(lock: &hiddev->list_lock, flags);
158
159 wake_up_interruptible(&hiddev->wait);
160}
161
162/*
163 * This is where hid.c calls into hiddev to pass an event that occurred over
164 * the interrupt pipe
165 */
166void hiddev_hid_event(struct hid_device *hid, struct hid_field *field,
167 struct hid_usage *usage, __s32 value)
168{
169 unsigned type = field->report_type;
170 struct hiddev_usage_ref uref;
171
172 uref.report_type =
173 (type == HID_INPUT_REPORT) ? HID_REPORT_TYPE_INPUT :
174 ((type == HID_OUTPUT_REPORT) ? HID_REPORT_TYPE_OUTPUT :
175 ((type == HID_FEATURE_REPORT) ? HID_REPORT_TYPE_FEATURE : 0));
176 uref.report_id = field->report->id;
177 uref.field_index = field->index;
178 uref.usage_index = (usage - field->usage);
179 uref.usage_code = usage->hid;
180 uref.value = value;
181
182 hiddev_send_event(hid, uref: &uref);
183}
184EXPORT_SYMBOL_GPL(hiddev_hid_event);
185
186void hiddev_report_event(struct hid_device *hid, struct hid_report *report)
187{
188 unsigned type = report->type;
189 struct hiddev_usage_ref uref;
190
191 memset(s: &uref, c: 0, n: sizeof(uref));
192 uref.report_type =
193 (type == HID_INPUT_REPORT) ? HID_REPORT_TYPE_INPUT :
194 ((type == HID_OUTPUT_REPORT) ? HID_REPORT_TYPE_OUTPUT :
195 ((type == HID_FEATURE_REPORT) ? HID_REPORT_TYPE_FEATURE : 0));
196 uref.report_id = report->id;
197 uref.field_index = HID_FIELD_INDEX_NONE;
198
199 hiddev_send_event(hid, uref: &uref);
200}
201
202/*
203 * fasync file op
204 */
205static int hiddev_fasync(int fd, struct file *file, int on)
206{
207 struct hiddev_list *list = file->private_data;
208
209 return fasync_helper(fd, file, on, &list->fasync);
210}
211
212
213/*
214 * release file op
215 */
216static int hiddev_release(struct inode * inode, struct file * file)
217{
218 struct hiddev_list *list = file->private_data;
219 unsigned long flags;
220
221 spin_lock_irqsave(&list->hiddev->list_lock, flags);
222 list_del(entry: &list->node);
223 spin_unlock_irqrestore(lock: &list->hiddev->list_lock, flags);
224
225 mutex_lock(lock: &list->hiddev->existancelock);
226 if (!--list->hiddev->open) {
227 if (list->hiddev->exist) {
228 hid_hw_close(hdev: list->hiddev->hid);
229 hid_hw_power(hdev: list->hiddev->hid, PM_HINT_NORMAL);
230 } else {
231 mutex_unlock(lock: &list->hiddev->existancelock);
232 kfree(objp: list->hiddev);
233 vfree(addr: list);
234 return 0;
235 }
236 }
237
238 mutex_unlock(lock: &list->hiddev->existancelock);
239 vfree(addr: list);
240
241 return 0;
242}
243
244static int __hiddev_open(struct hiddev *hiddev, struct file *file)
245{
246 struct hiddev_list *list;
247 int error;
248
249 lockdep_assert_held(&hiddev->existancelock);
250
251 list = vzalloc(sizeof(*list));
252 if (!list)
253 return -ENOMEM;
254
255 mutex_init(&list->thread_lock);
256 list->hiddev = hiddev;
257
258 if (!hiddev->open++) {
259 error = hid_hw_power(hdev: hiddev->hid, PM_HINT_FULLON);
260 if (error < 0)
261 goto err_drop_count;
262
263 error = hid_hw_open(hdev: hiddev->hid);
264 if (error < 0)
265 goto err_normal_power;
266 }
267
268 spin_lock_irq(lock: &hiddev->list_lock);
269 list_add_tail(new: &list->node, head: &hiddev->list);
270 spin_unlock_irq(lock: &hiddev->list_lock);
271
272 file->private_data = list;
273
274 return 0;
275
276err_normal_power:
277 hid_hw_power(hdev: hiddev->hid, PM_HINT_NORMAL);
278err_drop_count:
279 hiddev->open--;
280 vfree(addr: list);
281 return error;
282}
283
284/*
285 * open file op
286 */
287static int hiddev_open(struct inode *inode, struct file *file)
288{
289 struct usb_interface *intf;
290 struct hid_device *hid;
291 struct hiddev *hiddev;
292 int res;
293
294 intf = usbhid_find_interface(minor: iminor(inode));
295 if (!intf)
296 return -ENODEV;
297
298 hid = usb_get_intfdata(intf);
299 hiddev = hid->hiddev;
300
301 mutex_lock(lock: &hiddev->existancelock);
302 res = hiddev->exist ? __hiddev_open(hiddev, file) : -ENODEV;
303 mutex_unlock(lock: &hiddev->existancelock);
304
305 return res;
306}
307
308/*
309 * "write" file op
310 */
311static ssize_t hiddev_write(struct file * file, const char __user * buffer, size_t count, loff_t *ppos)
312{
313 return -EINVAL;
314}
315
316/*
317 * "read" file op
318 */
319static ssize_t hiddev_read(struct file * file, char __user * buffer, size_t count, loff_t *ppos)
320{
321 DEFINE_WAIT(wait);
322 struct hiddev_list *list = file->private_data;
323 int event_size;
324 int retval;
325
326 event_size = ((list->flags & HIDDEV_FLAG_UREF) != 0) ?
327 sizeof(struct hiddev_usage_ref) : sizeof(struct hiddev_event);
328
329 if (count < event_size)
330 return 0;
331
332 /* lock against other threads */
333 retval = mutex_lock_interruptible(lock: &list->thread_lock);
334 if (retval)
335 return -ERESTARTSYS;
336
337 while (retval == 0) {
338 if (list->head == list->tail) {
339 prepare_to_wait(wq_head: &list->hiddev->wait, wq_entry: &wait, TASK_INTERRUPTIBLE);
340
341 while (list->head == list->tail) {
342 if (signal_pending(current)) {
343 retval = -ERESTARTSYS;
344 break;
345 }
346 if (!list->hiddev->exist) {
347 retval = -EIO;
348 break;
349 }
350 if (file->f_flags & O_NONBLOCK) {
351 retval = -EAGAIN;
352 break;
353 }
354
355 /* let O_NONBLOCK tasks run */
356 mutex_unlock(lock: &list->thread_lock);
357 schedule();
358 if (mutex_lock_interruptible(lock: &list->thread_lock)) {
359 finish_wait(wq_head: &list->hiddev->wait, wq_entry: &wait);
360 return -EINTR;
361 }
362 set_current_state(TASK_INTERRUPTIBLE);
363 }
364 finish_wait(wq_head: &list->hiddev->wait, wq_entry: &wait);
365
366 }
367
368 if (retval) {
369 mutex_unlock(lock: &list->thread_lock);
370 return retval;
371 }
372
373
374 while (list->head != list->tail &&
375 retval + event_size <= count) {
376 if ((list->flags & HIDDEV_FLAG_UREF) == 0) {
377 if (list->buffer[list->tail].field_index != HID_FIELD_INDEX_NONE) {
378 struct hiddev_event event;
379
380 event.hid = list->buffer[list->tail].usage_code;
381 event.value = list->buffer[list->tail].value;
382 if (copy_to_user(to: buffer + retval, from: &event, n: sizeof(struct hiddev_event))) {
383 mutex_unlock(lock: &list->thread_lock);
384 return -EFAULT;
385 }
386 retval += sizeof(struct hiddev_event);
387 }
388 } else {
389 if (list->buffer[list->tail].field_index != HID_FIELD_INDEX_NONE ||
390 (list->flags & HIDDEV_FLAG_REPORT) != 0) {
391
392 if (copy_to_user(to: buffer + retval, from: list->buffer + list->tail, n: sizeof(struct hiddev_usage_ref))) {
393 mutex_unlock(lock: &list->thread_lock);
394 return -EFAULT;
395 }
396 retval += sizeof(struct hiddev_usage_ref);
397 }
398 }
399 list->tail = (list->tail + 1) & (HIDDEV_BUFFER_SIZE - 1);
400 }
401
402 }
403 mutex_unlock(lock: &list->thread_lock);
404
405 return retval;
406}
407
408/*
409 * "poll" file op
410 * No kernel lock - fine
411 */
412static __poll_t hiddev_poll(struct file *file, poll_table *wait)
413{
414 struct hiddev_list *list = file->private_data;
415
416 poll_wait(filp: file, wait_address: &list->hiddev->wait, p: wait);
417 if (list->head != list->tail)
418 return EPOLLIN | EPOLLRDNORM | EPOLLOUT;
419 if (!list->hiddev->exist)
420 return EPOLLERR | EPOLLHUP;
421 return 0;
422}
423
424/*
425 * "ioctl" file op
426 */
427static noinline int hiddev_ioctl_usage(struct hiddev *hiddev, unsigned int cmd, void __user *user_arg)
428{
429 struct hid_device *hid = hiddev->hid;
430 struct hiddev_report_info rinfo;
431 struct hiddev_usage_ref_multi *uref_multi = NULL;
432 struct hiddev_usage_ref *uref;
433 struct hid_report *report;
434 struct hid_field *field;
435 int i;
436
437 uref_multi = kmalloc(sizeof(struct hiddev_usage_ref_multi), GFP_KERNEL);
438 if (!uref_multi)
439 return -ENOMEM;
440 uref = &uref_multi->uref;
441 if (cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) {
442 if (copy_from_user(to: uref_multi, from: user_arg,
443 n: sizeof(*uref_multi)))
444 goto fault;
445 } else {
446 if (copy_from_user(to: uref, from: user_arg, n: sizeof(*uref)))
447 goto fault;
448 }
449
450 switch (cmd) {
451 case HIDIOCGUCODE:
452 rinfo.report_type = uref->report_type;
453 rinfo.report_id = uref->report_id;
454 if ((report = hiddev_lookup_report(hid, rinfo: &rinfo)) == NULL)
455 goto inval;
456
457 if (uref->field_index >= report->maxfield)
458 goto inval;
459 uref->field_index = array_index_nospec(uref->field_index,
460 report->maxfield);
461
462 field = report->field[uref->field_index];
463 if (uref->usage_index >= field->maxusage)
464 goto inval;
465 uref->usage_index = array_index_nospec(uref->usage_index,
466 field->maxusage);
467
468 uref->usage_code = field->usage[uref->usage_index].hid;
469
470 if (copy_to_user(to: user_arg, from: uref, n: sizeof(*uref)))
471 goto fault;
472
473 goto goodreturn;
474
475 default:
476 if (cmd != HIDIOCGUSAGE &&
477 cmd != HIDIOCGUSAGES &&
478 uref->report_type == HID_REPORT_TYPE_INPUT)
479 goto inval;
480
481 if (uref->report_id == HID_REPORT_ID_UNKNOWN) {
482 field = hiddev_lookup_usage(hid, uref);
483 if (field == NULL)
484 goto inval;
485 } else {
486 rinfo.report_type = uref->report_type;
487 rinfo.report_id = uref->report_id;
488 if ((report = hiddev_lookup_report(hid, rinfo: &rinfo)) == NULL)
489 goto inval;
490
491 if (uref->field_index >= report->maxfield)
492 goto inval;
493 uref->field_index = array_index_nospec(uref->field_index,
494 report->maxfield);
495
496 field = report->field[uref->field_index];
497
498 if (cmd == HIDIOCGCOLLECTIONINDEX) {
499 if (uref->usage_index >= field->maxusage)
500 goto inval;
501 uref->usage_index =
502 array_index_nospec(uref->usage_index,
503 field->maxusage);
504 } else if (uref->usage_index >= field->report_count)
505 goto inval;
506 }
507
508 if (cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) {
509 if (uref_multi->num_values > HID_MAX_MULTI_USAGES ||
510 uref->usage_index + uref_multi->num_values >
511 field->report_count)
512 goto inval;
513
514 uref->usage_index =
515 array_index_nospec(uref->usage_index,
516 field->report_count -
517 uref_multi->num_values);
518 }
519
520 switch (cmd) {
521 case HIDIOCGUSAGE:
522 if (uref->usage_index >= field->report_count)
523 goto inval;
524 uref->value = field->value[uref->usage_index];
525 if (copy_to_user(to: user_arg, from: uref, n: sizeof(*uref)))
526 goto fault;
527 goto goodreturn;
528
529 case HIDIOCSUSAGE:
530 if (uref->usage_index >= field->report_count)
531 goto inval;
532 field->value[uref->usage_index] = uref->value;
533 goto goodreturn;
534
535 case HIDIOCGCOLLECTIONINDEX:
536 i = field->usage[uref->usage_index].collection_index;
537 kfree(objp: uref_multi);
538 return i;
539 case HIDIOCGUSAGES:
540 for (i = 0; i < uref_multi->num_values; i++)
541 uref_multi->values[i] =
542 field->value[uref->usage_index + i];
543 if (copy_to_user(to: user_arg, from: uref_multi,
544 n: sizeof(*uref_multi)))
545 goto fault;
546 goto goodreturn;
547 case HIDIOCSUSAGES:
548 for (i = 0; i < uref_multi->num_values; i++)
549 field->value[uref->usage_index + i] =
550 uref_multi->values[i];
551 goto goodreturn;
552 }
553
554goodreturn:
555 kfree(objp: uref_multi);
556 return 0;
557fault:
558 kfree(objp: uref_multi);
559 return -EFAULT;
560inval:
561 kfree(objp: uref_multi);
562 return -EINVAL;
563 }
564}
565
566static noinline int hiddev_ioctl_string(struct hiddev *hiddev, unsigned int cmd, void __user *user_arg)
567{
568 struct hid_device *hid = hiddev->hid;
569 struct usb_device *dev = hid_to_usb_dev(hid);
570 int idx, len;
571 char *buf;
572
573 if (get_user(idx, (int __user *)user_arg))
574 return -EFAULT;
575
576 if ((buf = kmalloc(HID_STRING_SIZE, GFP_KERNEL)) == NULL)
577 return -ENOMEM;
578
579 if ((len = usb_string(dev, index: idx, buf, HID_STRING_SIZE-1)) < 0) {
580 kfree(objp: buf);
581 return -EINVAL;
582 }
583
584 if (copy_to_user(to: user_arg+sizeof(int), from: buf, n: len+1)) {
585 kfree(objp: buf);
586 return -EFAULT;
587 }
588
589 kfree(objp: buf);
590
591 return len;
592}
593
594static long hiddev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
595{
596 struct hiddev_list *list = file->private_data;
597 struct hiddev *hiddev = list->hiddev;
598 struct hid_device *hid;
599 struct hiddev_collection_info cinfo;
600 struct hiddev_report_info rinfo;
601 struct hiddev_field_info finfo;
602 struct hiddev_devinfo dinfo;
603 struct hid_report *report;
604 struct hid_field *field;
605 void __user *user_arg = (void __user *)arg;
606 int i, r = -EINVAL;
607
608 /* Called without BKL by compat methods so no BKL taken */
609
610 mutex_lock(lock: &hiddev->existancelock);
611 if (!hiddev->exist) {
612 r = -ENODEV;
613 goto ret_unlock;
614 }
615
616 hid = hiddev->hid;
617
618 switch (cmd) {
619
620 case HIDIOCGVERSION:
621 r = put_user(HID_VERSION, (int __user *)arg) ?
622 -EFAULT : 0;
623 break;
624
625 case HIDIOCAPPLICATION:
626 if (arg >= hid->maxapplication)
627 break;
628
629 for (i = 0; i < hid->maxcollection; i++)
630 if (hid->collection[i].type ==
631 HID_COLLECTION_APPLICATION && arg-- == 0)
632 break;
633
634 if (i < hid->maxcollection)
635 r = hid->collection[i].usage;
636 break;
637
638 case HIDIOCGDEVINFO:
639 {
640 struct usb_device *dev = hid_to_usb_dev(hid);
641 struct usbhid_device *usbhid = hid->driver_data;
642
643 memset(s: &dinfo, c: 0, n: sizeof(dinfo));
644
645 dinfo.bustype = BUS_USB;
646 dinfo.busnum = dev->bus->busnum;
647 dinfo.devnum = dev->devnum;
648 dinfo.ifnum = usbhid->ifnum;
649 dinfo.vendor = le16_to_cpu(dev->descriptor.idVendor);
650 dinfo.product = le16_to_cpu(dev->descriptor.idProduct);
651 dinfo.version = le16_to_cpu(dev->descriptor.bcdDevice);
652 dinfo.num_applications = hid->maxapplication;
653
654 r = copy_to_user(to: user_arg, from: &dinfo, n: sizeof(dinfo)) ?
655 -EFAULT : 0;
656 break;
657 }
658
659 case HIDIOCGFLAG:
660 r = put_user(list->flags, (int __user *)arg) ?
661 -EFAULT : 0;
662 break;
663
664 case HIDIOCSFLAG:
665 {
666 int newflags;
667
668 if (get_user(newflags, (int __user *)arg)) {
669 r = -EFAULT;
670 break;
671 }
672
673 if ((newflags & ~HIDDEV_FLAGS) != 0 ||
674 ((newflags & HIDDEV_FLAG_REPORT) != 0 &&
675 (newflags & HIDDEV_FLAG_UREF) == 0))
676 break;
677
678 list->flags = newflags;
679
680 r = 0;
681 break;
682 }
683
684 case HIDIOCGSTRING:
685 r = hiddev_ioctl_string(hiddev, cmd, user_arg);
686 break;
687
688 case HIDIOCINITREPORT:
689 usbhid_init_reports(hid);
690 hiddev->initialized = true;
691 r = 0;
692 break;
693
694 case HIDIOCGREPORT:
695 if (copy_from_user(to: &rinfo, from: user_arg, n: sizeof(rinfo))) {
696 r = -EFAULT;
697 break;
698 }
699
700 if (rinfo.report_type == HID_REPORT_TYPE_OUTPUT)
701 break;
702
703 report = hiddev_lookup_report(hid, rinfo: &rinfo);
704 if (report == NULL)
705 break;
706
707 hid_hw_request(hdev: hid, report, reqtype: HID_REQ_GET_REPORT);
708 hid_hw_wait(hdev: hid);
709
710 r = 0;
711 break;
712
713 case HIDIOCSREPORT:
714 if (copy_from_user(to: &rinfo, from: user_arg, n: sizeof(rinfo))) {
715 r = -EFAULT;
716 break;
717 }
718
719 if (rinfo.report_type == HID_REPORT_TYPE_INPUT)
720 break;
721
722 report = hiddev_lookup_report(hid, rinfo: &rinfo);
723 if (report == NULL)
724 break;
725
726 hid_hw_request(hdev: hid, report, reqtype: HID_REQ_SET_REPORT);
727 hid_hw_wait(hdev: hid);
728
729 r = 0;
730 break;
731
732 case HIDIOCGREPORTINFO:
733 if (copy_from_user(to: &rinfo, from: user_arg, n: sizeof(rinfo))) {
734 r = -EFAULT;
735 break;
736 }
737
738 report = hiddev_lookup_report(hid, rinfo: &rinfo);
739 if (report == NULL)
740 break;
741
742 rinfo.num_fields = report->maxfield;
743
744 r = copy_to_user(to: user_arg, from: &rinfo, n: sizeof(rinfo)) ?
745 -EFAULT : 0;
746 break;
747
748 case HIDIOCGFIELDINFO:
749 if (copy_from_user(to: &finfo, from: user_arg, n: sizeof(finfo))) {
750 r = -EFAULT;
751 break;
752 }
753
754 rinfo.report_type = finfo.report_type;
755 rinfo.report_id = finfo.report_id;
756
757 report = hiddev_lookup_report(hid, rinfo: &rinfo);
758 if (report == NULL)
759 break;
760
761 if (finfo.field_index >= report->maxfield)
762 break;
763 finfo.field_index = array_index_nospec(finfo.field_index,
764 report->maxfield);
765
766 field = report->field[finfo.field_index];
767 memset(s: &finfo, c: 0, n: sizeof(finfo));
768 finfo.report_type = rinfo.report_type;
769 finfo.report_id = rinfo.report_id;
770 finfo.field_index = field->report_count - 1;
771 finfo.maxusage = field->maxusage;
772 finfo.flags = field->flags;
773 finfo.physical = field->physical;
774 finfo.logical = field->logical;
775 finfo.application = field->application;
776 finfo.logical_minimum = field->logical_minimum;
777 finfo.logical_maximum = field->logical_maximum;
778 finfo.physical_minimum = field->physical_minimum;
779 finfo.physical_maximum = field->physical_maximum;
780 finfo.unit_exponent = field->unit_exponent;
781 finfo.unit = field->unit;
782
783 r = copy_to_user(to: user_arg, from: &finfo, n: sizeof(finfo)) ?
784 -EFAULT : 0;
785 break;
786
787 case HIDIOCGUCODE:
788 case HIDIOCGUSAGE:
789 case HIDIOCSUSAGE:
790 case HIDIOCGUSAGES:
791 case HIDIOCSUSAGES:
792 case HIDIOCGCOLLECTIONINDEX:
793 if (!hiddev->initialized) {
794 usbhid_init_reports(hid);
795 hiddev->initialized = true;
796 }
797 r = hiddev_ioctl_usage(hiddev, cmd, user_arg);
798 break;
799
800 case HIDIOCGCOLLECTIONINFO:
801 if (copy_from_user(to: &cinfo, from: user_arg, n: sizeof(cinfo))) {
802 r = -EFAULT;
803 break;
804 }
805
806 if (cinfo.index >= hid->maxcollection)
807 break;
808 cinfo.index = array_index_nospec(cinfo.index,
809 hid->maxcollection);
810
811 cinfo.type = hid->collection[cinfo.index].type;
812 cinfo.usage = hid->collection[cinfo.index].usage;
813 cinfo.level = hid->collection[cinfo.index].level;
814
815 r = copy_to_user(to: user_arg, from: &cinfo, n: sizeof(cinfo)) ?
816 -EFAULT : 0;
817 break;
818
819 default:
820 if (_IOC_TYPE(cmd) != 'H' || _IOC_DIR(cmd) != _IOC_READ)
821 break;
822
823 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGNAME(0))) {
824 int len = strlen(hid->name) + 1;
825 if (len > _IOC_SIZE(cmd))
826 len = _IOC_SIZE(cmd);
827 r = copy_to_user(to: user_arg, from: hid->name, n: len) ?
828 -EFAULT : len;
829 break;
830 }
831
832 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGPHYS(0))) {
833 int len = strlen(hid->phys) + 1;
834 if (len > _IOC_SIZE(cmd))
835 len = _IOC_SIZE(cmd);
836 r = copy_to_user(to: user_arg, from: hid->phys, n: len) ?
837 -EFAULT : len;
838 break;
839 }
840 }
841
842ret_unlock:
843 mutex_unlock(lock: &hiddev->existancelock);
844 return r;
845}
846
847static const struct file_operations hiddev_fops = {
848 .owner = THIS_MODULE,
849 .read = hiddev_read,
850 .write = hiddev_write,
851 .poll = hiddev_poll,
852 .open = hiddev_open,
853 .release = hiddev_release,
854 .unlocked_ioctl = hiddev_ioctl,
855 .fasync = hiddev_fasync,
856 .compat_ioctl = compat_ptr_ioctl,
857 .llseek = noop_llseek,
858};
859
860static char *hiddev_devnode(const struct device *dev, umode_t *mode)
861{
862 return kasprintf(GFP_KERNEL, fmt: "usb/%s", dev_name(dev));
863}
864
865static struct usb_class_driver hiddev_class = {
866 .name = "hiddev%d",
867 .devnode = hiddev_devnode,
868 .fops = &hiddev_fops,
869 .minor_base = HIDDEV_MINOR_BASE,
870};
871
872/*
873 * This is where hid.c calls us to connect a hid device to the hiddev driver
874 */
875int hiddev_connect(struct hid_device *hid, unsigned int force)
876{
877 struct hiddev *hiddev;
878 struct usbhid_device *usbhid = hid->driver_data;
879 int retval;
880
881 if (!force) {
882 unsigned int i;
883 for (i = 0; i < hid->maxcollection; i++)
884 if (hid->collection[i].type ==
885 HID_COLLECTION_APPLICATION &&
886 !IS_INPUT_APPLICATION(hid->collection[i].usage))
887 break;
888
889 if (i == hid->maxcollection)
890 return -EINVAL;
891 }
892
893 if (!(hiddev = kzalloc(sizeof(struct hiddev), GFP_KERNEL)))
894 return -ENOMEM;
895
896 init_waitqueue_head(&hiddev->wait);
897 INIT_LIST_HEAD(list: &hiddev->list);
898 spin_lock_init(&hiddev->list_lock);
899 mutex_init(&hiddev->existancelock);
900 hid->hiddev = hiddev;
901 hiddev->hid = hid;
902 hiddev->exist = 1;
903 retval = usb_register_dev(intf: usbhid->intf, class_driver: &hiddev_class);
904 if (retval) {
905 hid_err(hid, "Not able to get a minor for this device\n");
906 hid->hiddev = NULL;
907 kfree(objp: hiddev);
908 return retval;
909 }
910
911 /*
912 * If HID_QUIRK_NO_INIT_REPORTS is set, make sure we don't initialize
913 * the reports.
914 */
915 hiddev->initialized = hid->quirks & HID_QUIRK_NO_INIT_REPORTS;
916
917 hiddev->minor = usbhid->intf->minor;
918
919 return 0;
920}
921
922/*
923 * This is where hid.c calls us to disconnect a hiddev device from the
924 * corresponding hid device (usually because the usb device has disconnected)
925 */
926static struct usb_class_driver hiddev_class;
927void hiddev_disconnect(struct hid_device *hid)
928{
929 struct hiddev *hiddev = hid->hiddev;
930 struct usbhid_device *usbhid = hid->driver_data;
931
932 usb_deregister_dev(intf: usbhid->intf, class_driver: &hiddev_class);
933
934 mutex_lock(lock: &hiddev->existancelock);
935 hiddev->exist = 0;
936
937 if (hiddev->open) {
938 hid_hw_close(hdev: hiddev->hid);
939 wake_up_interruptible(&hiddev->wait);
940 mutex_unlock(lock: &hiddev->existancelock);
941 } else {
942 mutex_unlock(lock: &hiddev->existancelock);
943 kfree(objp: hiddev);
944 }
945}
946