blob: e707da0b1fe2e1bbad544dff53967e719b56124c [file] [log] [blame]
b.liue9582032025-04-17 19:18:16 +08001// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * User level driver support for input subsystem
4 *
5 * Heavily based on evdev.c by Vojtech Pavlik
6 *
7 * Author: Aristeu Sergio Rozanski Filho <aris@cathedrallabs.org>
8 *
9 * Changes/Revisions:
10 * 0.4 01/09/2014 (Benjamin Tissoires <benjamin.tissoires@redhat.com>)
11 * - add UI_GET_SYSNAME ioctl
12 * 0.3 09/04/2006 (Anssi Hannula <anssi.hannula@gmail.com>)
13 * - updated ff support for the changes in kernel interface
14 * - added MODULE_VERSION
15 * 0.2 16/10/2004 (Micah Dowty <micah@navi.cx>)
16 * - added force feedback support
17 * - added UI_SET_PHYS
18 * 0.1 20/06/2002
19 * - first public version
20 */
21#include <uapi/linux/uinput.h>
22#include <linux/poll.h>
23#include <linux/sched.h>
24#include <linux/slab.h>
25#include <linux/module.h>
26#include <linux/init.h>
27#include <linux/fs.h>
28#include <linux/miscdevice.h>
29#include <linux/overflow.h>
30#include <linux/input/mt.h>
31#include "../input-compat.h"
32
33#define UINPUT_NAME "uinput"
34#define UINPUT_BUFFER_SIZE 16
35#define UINPUT_NUM_REQUESTS 16
36
37enum uinput_state { UIST_NEW_DEVICE, UIST_SETUP_COMPLETE, UIST_CREATED };
38
39struct uinput_request {
40 unsigned int id;
41 unsigned int code; /* UI_FF_UPLOAD, UI_FF_ERASE */
42
43 int retval;
44 struct completion done;
45
46 union {
47 unsigned int effect_id;
48 struct {
49 struct ff_effect *effect;
50 struct ff_effect *old;
51 } upload;
52 } u;
53};
54
55struct uinput_device {
56 struct input_dev *dev;
57 struct mutex mutex;
58 enum uinput_state state;
59 wait_queue_head_t waitq;
60 unsigned char ready;
61 unsigned char head;
62 unsigned char tail;
63 struct input_event buff[UINPUT_BUFFER_SIZE];
64 unsigned int ff_effects_max;
65
66 struct uinput_request *requests[UINPUT_NUM_REQUESTS];
67 wait_queue_head_t requests_waitq;
68 spinlock_t requests_lock;
69};
70
71static int uinput_dev_event(struct input_dev *dev,
72 unsigned int type, unsigned int code, int value)
73{
74 struct uinput_device *udev = input_get_drvdata(dev);
75 struct timespec64 ts;
76
77 ktime_get_ts64(&ts);
78
79 udev->buff[udev->head] = (struct input_event) {
80 .input_event_sec = ts.tv_sec,
81 .input_event_usec = ts.tv_nsec / NSEC_PER_USEC,
82 .type = type,
83 .code = code,
84 .value = value,
85 };
86
87 udev->head = (udev->head + 1) % UINPUT_BUFFER_SIZE;
88
89 wake_up_interruptible(&udev->waitq);
90
91 return 0;
92}
93
94/* Atomically allocate an ID for the given request. Returns 0 on success. */
95static bool uinput_request_alloc_id(struct uinput_device *udev,
96 struct uinput_request *request)
97{
98 unsigned int id;
99 bool reserved = false;
100
101 spin_lock(&udev->requests_lock);
102
103 for (id = 0; id < UINPUT_NUM_REQUESTS; id++) {
104 if (!udev->requests[id]) {
105 request->id = id;
106 udev->requests[id] = request;
107 reserved = true;
108 break;
109 }
110 }
111
112 spin_unlock(&udev->requests_lock);
113 return reserved;
114}
115
116static struct uinput_request *uinput_request_find(struct uinput_device *udev,
117 unsigned int id)
118{
119 /* Find an input request, by ID. Returns NULL if the ID isn't valid. */
120 if (id >= UINPUT_NUM_REQUESTS)
121 return NULL;
122
123 return udev->requests[id];
124}
125
126static int uinput_request_reserve_slot(struct uinput_device *udev,
127 struct uinput_request *request)
128{
129 /* Allocate slot. If none are available right away, wait. */
130 return wait_event_interruptible(udev->requests_waitq,
131 uinput_request_alloc_id(udev, request));
132}
133
134static void uinput_request_release_slot(struct uinput_device *udev,
135 unsigned int id)
136{
137 /* Mark slot as available */
138 spin_lock(&udev->requests_lock);
139 udev->requests[id] = NULL;
140 spin_unlock(&udev->requests_lock);
141
142 wake_up(&udev->requests_waitq);
143}
144
145static int uinput_request_send(struct uinput_device *udev,
146 struct uinput_request *request)
147{
148 int retval;
149
150 retval = mutex_lock_interruptible(&udev->mutex);
151 if (retval)
152 return retval;
153
154 if (udev->state != UIST_CREATED) {
155 retval = -ENODEV;
156 goto out;
157 }
158
159 init_completion(&request->done);
160
161 /*
162 * Tell our userspace application about this new request
163 * by queueing an input event.
164 */
165 uinput_dev_event(udev->dev, EV_UINPUT, request->code, request->id);
166
167 out:
168 mutex_unlock(&udev->mutex);
169 return retval;
170}
171
172static int uinput_request_submit(struct uinput_device *udev,
173 struct uinput_request *request)
174{
175 int retval;
176
177 retval = uinput_request_reserve_slot(udev, request);
178 if (retval)
179 return retval;
180
181 retval = uinput_request_send(udev, request);
182 if (retval)
183 goto out;
184
185 if (!wait_for_completion_timeout(&request->done, 30 * HZ)) {
186 retval = -ETIMEDOUT;
187 goto out;
188 }
189
190 retval = request->retval;
191
192 out:
193 uinput_request_release_slot(udev, request->id);
194 return retval;
195}
196
197/*
198 * Fail all outstanding requests so handlers don't wait for the userspace
199 * to finish processing them.
200 */
201static void uinput_flush_requests(struct uinput_device *udev)
202{
203 struct uinput_request *request;
204 int i;
205
206 spin_lock(&udev->requests_lock);
207
208 for (i = 0; i < UINPUT_NUM_REQUESTS; i++) {
209 request = udev->requests[i];
210 if (request) {
211 request->retval = -ENODEV;
212 complete(&request->done);
213 }
214 }
215
216 spin_unlock(&udev->requests_lock);
217}
218
219static void uinput_dev_set_gain(struct input_dev *dev, u16 gain)
220{
221 uinput_dev_event(dev, EV_FF, FF_GAIN, gain);
222}
223
224static void uinput_dev_set_autocenter(struct input_dev *dev, u16 magnitude)
225{
226 uinput_dev_event(dev, EV_FF, FF_AUTOCENTER, magnitude);
227}
228
229static int uinput_dev_playback(struct input_dev *dev, int effect_id, int value)
230{
231 return uinput_dev_event(dev, EV_FF, effect_id, value);
232}
233
234static int uinput_dev_upload_effect(struct input_dev *dev,
235 struct ff_effect *effect,
236 struct ff_effect *old)
237{
238 struct uinput_device *udev = input_get_drvdata(dev);
239 struct uinput_request request;
240
241 /*
242 * uinput driver does not currently support periodic effects with
243 * custom waveform since it does not have a way to pass buffer of
244 * samples (custom_data) to userspace. If ever there is a device
245 * supporting custom waveforms we would need to define an additional
246 * ioctl (UI_UPLOAD_SAMPLES) but for now we just bail out.
247 */
248 if (effect->type == FF_PERIODIC &&
249 effect->u.periodic.waveform == FF_CUSTOM)
250 return -EINVAL;
251
252 request.code = UI_FF_UPLOAD;
253 request.u.upload.effect = effect;
254 request.u.upload.old = old;
255
256 return uinput_request_submit(udev, &request);
257}
258
259static int uinput_dev_erase_effect(struct input_dev *dev, int effect_id)
260{
261 struct uinput_device *udev = input_get_drvdata(dev);
262 struct uinput_request request;
263
264 if (!test_bit(EV_FF, dev->evbit))
265 return -ENOSYS;
266
267 request.code = UI_FF_ERASE;
268 request.u.effect_id = effect_id;
269
270 return uinput_request_submit(udev, &request);
271}
272
273static int uinput_dev_flush(struct input_dev *dev, struct file *file)
274{
275 /*
276 * If we are called with file == NULL that means we are tearing
277 * down the device, and therefore we can not handle FF erase
278 * requests: either we are handling UI_DEV_DESTROY (and holding
279 * the udev->mutex), or the file descriptor is closed and there is
280 * nobody on the other side anymore.
281 */
282 return file ? input_ff_flush(dev, file) : 0;
283}
284
285static void uinput_destroy_device(struct uinput_device *udev)
286{
287 const char *name, *phys;
288 struct input_dev *dev = udev->dev;
289 enum uinput_state old_state = udev->state;
290
291 udev->state = UIST_NEW_DEVICE;
292
293 if (dev) {
294 name = dev->name;
295 phys = dev->phys;
296 if (old_state == UIST_CREATED) {
297 uinput_flush_requests(udev);
298 input_unregister_device(dev);
299 } else {
300 input_free_device(dev);
301 }
302 kfree(name);
303 kfree(phys);
304 udev->dev = NULL;
305 }
306}
307
308static int uinput_create_device(struct uinput_device *udev)
309{
310 struct input_dev *dev = udev->dev;
311 int error, nslot;
312
313 if (udev->state != UIST_SETUP_COMPLETE) {
314 printk(KERN_DEBUG "%s: write device info first\n", UINPUT_NAME);
315 return -EINVAL;
316 }
317
318 if (test_bit(EV_ABS, dev->evbit)) {
319 input_alloc_absinfo(dev);
320 if (!dev->absinfo) {
321 error = -EINVAL;
322 goto fail1;
323 }
324
325 if (test_bit(ABS_MT_SLOT, dev->absbit)) {
326 nslot = input_abs_get_max(dev, ABS_MT_SLOT) + 1;
327 error = input_mt_init_slots(dev, nslot, 0);
328 if (error)
329 goto fail1;
330 } else if (test_bit(ABS_MT_POSITION_X, dev->absbit)) {
331 input_set_events_per_packet(dev, 60);
332 }
333 }
334
335 if (test_bit(EV_FF, dev->evbit) && !udev->ff_effects_max) {
336 printk(KERN_DEBUG "%s: ff_effects_max should be non-zero when FF_BIT is set\n",
337 UINPUT_NAME);
338 error = -EINVAL;
339 goto fail1;
340 }
341
342 if (udev->ff_effects_max) {
343 error = input_ff_create(dev, udev->ff_effects_max);
344 if (error)
345 goto fail1;
346
347 dev->ff->upload = uinput_dev_upload_effect;
348 dev->ff->erase = uinput_dev_erase_effect;
349 dev->ff->playback = uinput_dev_playback;
350 dev->ff->set_gain = uinput_dev_set_gain;
351 dev->ff->set_autocenter = uinput_dev_set_autocenter;
352 /*
353 * The standard input_ff_flush() implementation does
354 * not quite work for uinput as we can't reasonably
355 * handle FF requests during device teardown.
356 */
357 dev->flush = uinput_dev_flush;
358 }
359
360 dev->event = uinput_dev_event;
361
362 input_set_drvdata(udev->dev, udev);
363
364 error = input_register_device(udev->dev);
365 if (error)
366 goto fail2;
367
368 udev->state = UIST_CREATED;
369
370 return 0;
371
372 fail2: input_ff_destroy(dev);
373 fail1: uinput_destroy_device(udev);
374 return error;
375}
376
377static int uinput_open(struct inode *inode, struct file *file)
378{
379 struct uinput_device *newdev;
380
381 newdev = kzalloc(sizeof(struct uinput_device), GFP_KERNEL);
382 if (!newdev)
383 return -ENOMEM;
384
385 mutex_init(&newdev->mutex);
386 spin_lock_init(&newdev->requests_lock);
387 init_waitqueue_head(&newdev->requests_waitq);
388 init_waitqueue_head(&newdev->waitq);
389 newdev->state = UIST_NEW_DEVICE;
390
391 file->private_data = newdev;
392 stream_open(inode, file);
393
394 return 0;
395}
396
397static int uinput_validate_absinfo(struct input_dev *dev, unsigned int code,
398 const struct input_absinfo *abs)
399{
400 int min, max, range;
401
402 min = abs->minimum;
403 max = abs->maximum;
404
405 if ((min != 0 || max != 0) && max < min) {
406 printk(KERN_DEBUG
407 "%s: invalid abs[%02x] min:%d max:%d\n",
408 UINPUT_NAME, code, min, max);
409 return -EINVAL;
410 }
411
412 if (!check_sub_overflow(max, min, &range) && abs->flat > range) {
413 printk(KERN_DEBUG
414 "%s: abs_flat #%02x out of range: %d (min:%d/max:%d)\n",
415 UINPUT_NAME, code, abs->flat, min, max);
416 return -EINVAL;
417 }
418
419 /*
420 * Limit number of contacts to a reasonable value (100). This
421 * ensures that we need less than 2 pages for struct input_mt
422 * (we are not using in-kernel slot assignment so not going to
423 * allocate memory for the "red" table), and we should have no
424 * trouble getting this much memory.
425 */
426 if (code == ABS_MT_SLOT && max > 99) {
427 printk(KERN_DEBUG
428 "%s: unreasonably large number of slots requested: %d\n",
429 UINPUT_NAME, max);
430 return -EINVAL;
431 }
432
433 return 0;
434}
435
436static int uinput_validate_absbits(struct input_dev *dev)
437{
438 unsigned int cnt;
439 int error;
440
441 if (!test_bit(EV_ABS, dev->evbit))
442 return 0;
443
444 /*
445 * Check if absmin/absmax/absfuzz/absflat are sane.
446 */
447
448 for_each_set_bit(cnt, dev->absbit, ABS_CNT) {
449 if (!dev->absinfo)
450 return -EINVAL;
451
452 error = uinput_validate_absinfo(dev, cnt, &dev->absinfo[cnt]);
453 if (error)
454 return error;
455 }
456
457 return 0;
458}
459
460static int uinput_dev_setup(struct uinput_device *udev,
461 struct uinput_setup __user *arg)
462{
463 struct uinput_setup setup;
464 struct input_dev *dev;
465
466 if (udev->state == UIST_CREATED)
467 return -EINVAL;
468
469 if (copy_from_user(&setup, arg, sizeof(setup)))
470 return -EFAULT;
471
472 if (!setup.name[0])
473 return -EINVAL;
474
475 dev = udev->dev;
476 dev->id = setup.id;
477 udev->ff_effects_max = setup.ff_effects_max;
478
479 kfree(dev->name);
480 dev->name = kstrndup(setup.name, UINPUT_MAX_NAME_SIZE, GFP_KERNEL);
481 if (!dev->name)
482 return -ENOMEM;
483
484 udev->state = UIST_SETUP_COMPLETE;
485 return 0;
486}
487
488static int uinput_abs_setup(struct uinput_device *udev,
489 struct uinput_setup __user *arg, size_t size)
490{
491 struct uinput_abs_setup setup = {};
492 struct input_dev *dev;
493 int error;
494
495 if (size > sizeof(setup))
496 return -E2BIG;
497
498 if (udev->state == UIST_CREATED)
499 return -EINVAL;
500
501 if (copy_from_user(&setup, arg, size))
502 return -EFAULT;
503
504 if (setup.code > ABS_MAX)
505 return -ERANGE;
506
507 dev = udev->dev;
508
509 error = uinput_validate_absinfo(dev, setup.code, &setup.absinfo);
510 if (error)
511 return error;
512
513 input_alloc_absinfo(dev);
514 if (!dev->absinfo)
515 return -ENOMEM;
516
517 set_bit(setup.code, dev->absbit);
518 dev->absinfo[setup.code] = setup.absinfo;
519 return 0;
520}
521
522/* legacy setup via write() */
523static int uinput_setup_device_legacy(struct uinput_device *udev,
524 const char __user *buffer, size_t count)
525{
526 struct uinput_user_dev *user_dev;
527 struct input_dev *dev;
528 int i;
529 int retval;
530
531 if (count != sizeof(struct uinput_user_dev))
532 return -EINVAL;
533
534 if (!udev->dev) {
535 udev->dev = input_allocate_device();
536 if (!udev->dev)
537 return -ENOMEM;
538 }
539
540 dev = udev->dev;
541
542 user_dev = memdup_user(buffer, sizeof(struct uinput_user_dev));
543 if (IS_ERR(user_dev))
544 return PTR_ERR(user_dev);
545
546 udev->ff_effects_max = user_dev->ff_effects_max;
547
548 /* Ensure name is filled in */
549 if (!user_dev->name[0]) {
550 retval = -EINVAL;
551 goto exit;
552 }
553
554 kfree(dev->name);
555 dev->name = kstrndup(user_dev->name, UINPUT_MAX_NAME_SIZE,
556 GFP_KERNEL);
557 if (!dev->name) {
558 retval = -ENOMEM;
559 goto exit;
560 }
561
562 dev->id.bustype = user_dev->id.bustype;
563 dev->id.vendor = user_dev->id.vendor;
564 dev->id.product = user_dev->id.product;
565 dev->id.version = user_dev->id.version;
566
567 for (i = 0; i < ABS_CNT; i++) {
568 input_abs_set_max(dev, i, user_dev->absmax[i]);
569 input_abs_set_min(dev, i, user_dev->absmin[i]);
570 input_abs_set_fuzz(dev, i, user_dev->absfuzz[i]);
571 input_abs_set_flat(dev, i, user_dev->absflat[i]);
572 }
573
574 retval = uinput_validate_absbits(dev);
575 if (retval < 0)
576 goto exit;
577
578 udev->state = UIST_SETUP_COMPLETE;
579 retval = count;
580
581 exit:
582 kfree(user_dev);
583 return retval;
584}
585
586static ssize_t uinput_inject_events(struct uinput_device *udev,
587 const char __user *buffer, size_t count)
588{
589 struct input_event ev;
590 size_t bytes = 0;
591
592 if (count != 0 && count < input_event_size())
593 return -EINVAL;
594
595 while (bytes + input_event_size() <= count) {
596 /*
597 * Note that even if some events were fetched successfully
598 * we are still going to return EFAULT instead of partial
599 * count to let userspace know that it got it's buffers
600 * all wrong.
601 */
602 if (input_event_from_user(buffer + bytes, &ev))
603 return -EFAULT;
604
605 input_event(udev->dev, ev.type, ev.code, ev.value);
606 bytes += input_event_size();
607 cond_resched();
608 }
609
610 return bytes;
611}
612
613static ssize_t uinput_write(struct file *file, const char __user *buffer,
614 size_t count, loff_t *ppos)
615{
616 struct uinput_device *udev = file->private_data;
617 int retval;
618
619 if (count == 0)
620 return 0;
621
622 retval = mutex_lock_interruptible(&udev->mutex);
623 if (retval)
624 return retval;
625
626 retval = udev->state == UIST_CREATED ?
627 uinput_inject_events(udev, buffer, count) :
628 uinput_setup_device_legacy(udev, buffer, count);
629
630 mutex_unlock(&udev->mutex);
631
632 return retval;
633}
634
635static bool uinput_fetch_next_event(struct uinput_device *udev,
636 struct input_event *event)
637{
638 bool have_event;
639
640 spin_lock_irq(&udev->dev->event_lock);
641
642 have_event = udev->head != udev->tail;
643 if (have_event) {
644 *event = udev->buff[udev->tail];
645 udev->tail = (udev->tail + 1) % UINPUT_BUFFER_SIZE;
646 }
647
648 spin_unlock_irq(&udev->dev->event_lock);
649
650 return have_event;
651}
652
653static ssize_t uinput_events_to_user(struct uinput_device *udev,
654 char __user *buffer, size_t count)
655{
656 struct input_event event;
657 size_t read = 0;
658
659 while (read + input_event_size() <= count &&
660 uinput_fetch_next_event(udev, &event)) {
661
662 if (input_event_to_user(buffer + read, &event))
663 return -EFAULT;
664
665 read += input_event_size();
666 }
667
668 return read;
669}
670
671static ssize_t uinput_read(struct file *file, char __user *buffer,
672 size_t count, loff_t *ppos)
673{
674 struct uinput_device *udev = file->private_data;
675 ssize_t retval;
676
677 if (count != 0 && count < input_event_size())
678 return -EINVAL;
679
680 do {
681 retval = mutex_lock_interruptible(&udev->mutex);
682 if (retval)
683 return retval;
684
685 if (udev->state != UIST_CREATED)
686 retval = -ENODEV;
687 else if (udev->head == udev->tail &&
688 (file->f_flags & O_NONBLOCK))
689 retval = -EAGAIN;
690 else
691 retval = uinput_events_to_user(udev, buffer, count);
692
693 mutex_unlock(&udev->mutex);
694
695 if (retval || count == 0)
696 break;
697
698 if (!(file->f_flags & O_NONBLOCK))
699 retval = wait_event_interruptible(udev->waitq,
700 udev->head != udev->tail ||
701 udev->state != UIST_CREATED);
702 } while (retval == 0);
703
704 return retval;
705}
706
707static __poll_t uinput_poll(struct file *file, poll_table *wait)
708{
709 struct uinput_device *udev = file->private_data;
710
711 poll_wait(file, &udev->waitq, wait);
712
713 if (udev->head != udev->tail)
714 return EPOLLIN | EPOLLRDNORM;
715
716 return 0;
717}
718
719static int uinput_release(struct inode *inode, struct file *file)
720{
721 struct uinput_device *udev = file->private_data;
722
723 uinput_destroy_device(udev);
724 kfree(udev);
725
726 return 0;
727}
728
729#ifdef CONFIG_COMPAT
730struct uinput_ff_upload_compat {
731 __u32 request_id;
732 __s32 retval;
733 struct ff_effect_compat effect;
734 struct ff_effect_compat old;
735};
736
737static int uinput_ff_upload_to_user(char __user *buffer,
738 const struct uinput_ff_upload *ff_up)
739{
740 if (in_compat_syscall()) {
741 struct uinput_ff_upload_compat ff_up_compat;
742
743 ff_up_compat.request_id = ff_up->request_id;
744 ff_up_compat.retval = ff_up->retval;
745 /*
746 * It so happens that the pointer that gives us the trouble
747 * is the last field in the structure. Since we don't support
748 * custom waveforms in uinput anyway we can just copy the whole
749 * thing (to the compat size) and ignore the pointer.
750 */
751 memcpy(&ff_up_compat.effect, &ff_up->effect,
752 sizeof(struct ff_effect_compat));
753 memcpy(&ff_up_compat.old, &ff_up->old,
754 sizeof(struct ff_effect_compat));
755
756 if (copy_to_user(buffer, &ff_up_compat,
757 sizeof(struct uinput_ff_upload_compat)))
758 return -EFAULT;
759 } else {
760 if (copy_to_user(buffer, ff_up,
761 sizeof(struct uinput_ff_upload)))
762 return -EFAULT;
763 }
764
765 return 0;
766}
767
768static int uinput_ff_upload_from_user(const char __user *buffer,
769 struct uinput_ff_upload *ff_up)
770{
771 if (in_compat_syscall()) {
772 struct uinput_ff_upload_compat ff_up_compat;
773
774 if (copy_from_user(&ff_up_compat, buffer,
775 sizeof(struct uinput_ff_upload_compat)))
776 return -EFAULT;
777
778 ff_up->request_id = ff_up_compat.request_id;
779 ff_up->retval = ff_up_compat.retval;
780 memcpy(&ff_up->effect, &ff_up_compat.effect,
781 sizeof(struct ff_effect_compat));
782 memcpy(&ff_up->old, &ff_up_compat.old,
783 sizeof(struct ff_effect_compat));
784
785 } else {
786 if (copy_from_user(ff_up, buffer,
787 sizeof(struct uinput_ff_upload)))
788 return -EFAULT;
789 }
790
791 return 0;
792}
793
794#else
795
796static int uinput_ff_upload_to_user(char __user *buffer,
797 const struct uinput_ff_upload *ff_up)
798{
799 if (copy_to_user(buffer, ff_up, sizeof(struct uinput_ff_upload)))
800 return -EFAULT;
801
802 return 0;
803}
804
805static int uinput_ff_upload_from_user(const char __user *buffer,
806 struct uinput_ff_upload *ff_up)
807{
808 if (copy_from_user(ff_up, buffer, sizeof(struct uinput_ff_upload)))
809 return -EFAULT;
810
811 return 0;
812}
813
814#endif
815
816#define uinput_set_bit(_arg, _bit, _max) \
817({ \
818 int __ret = 0; \
819 if (udev->state == UIST_CREATED) \
820 __ret = -EINVAL; \
821 else if ((_arg) > (_max)) \
822 __ret = -EINVAL; \
823 else set_bit((_arg), udev->dev->_bit); \
824 __ret; \
825})
826
827static int uinput_str_to_user(void __user *dest, const char *str,
828 unsigned int maxlen)
829{
830 char __user *p = dest;
831 int len, ret;
832
833 if (!str)
834 return -ENOENT;
835
836 if (maxlen == 0)
837 return -EINVAL;
838
839 len = strlen(str) + 1;
840 if (len > maxlen)
841 len = maxlen;
842
843 ret = copy_to_user(p, str, len);
844 if (ret)
845 return -EFAULT;
846
847 /* force terminating '\0' */
848 ret = put_user(0, p + len - 1);
849 return ret ? -EFAULT : len;
850}
851
852static long uinput_ioctl_handler(struct file *file, unsigned int cmd,
853 unsigned long arg, void __user *p)
854{
855 int retval;
856 struct uinput_device *udev = file->private_data;
857 struct uinput_ff_upload ff_up;
858 struct uinput_ff_erase ff_erase;
859 struct uinput_request *req;
860 char *phys;
861 const char *name;
862 unsigned int size;
863
864 retval = mutex_lock_interruptible(&udev->mutex);
865 if (retval)
866 return retval;
867
868 if (!udev->dev) {
869 udev->dev = input_allocate_device();
870 if (!udev->dev) {
871 retval = -ENOMEM;
872 goto out;
873 }
874 }
875
876 switch (cmd) {
877 case UI_GET_VERSION:
878 if (put_user(UINPUT_VERSION, (unsigned int __user *)p))
879 retval = -EFAULT;
880 goto out;
881
882 case UI_DEV_CREATE:
883 retval = uinput_create_device(udev);
884 goto out;
885
886 case UI_DEV_DESTROY:
887 uinput_destroy_device(udev);
888 goto out;
889
890 case UI_DEV_SETUP:
891 retval = uinput_dev_setup(udev, p);
892 goto out;
893
894 /* UI_ABS_SETUP is handled in the variable size ioctls */
895
896 case UI_SET_EVBIT:
897 retval = uinput_set_bit(arg, evbit, EV_MAX);
898 goto out;
899
900 case UI_SET_KEYBIT:
901 retval = uinput_set_bit(arg, keybit, KEY_MAX);
902 goto out;
903
904 case UI_SET_RELBIT:
905 retval = uinput_set_bit(arg, relbit, REL_MAX);
906 goto out;
907
908 case UI_SET_ABSBIT:
909 retval = uinput_set_bit(arg, absbit, ABS_MAX);
910 goto out;
911
912 case UI_SET_MSCBIT:
913 retval = uinput_set_bit(arg, mscbit, MSC_MAX);
914 goto out;
915
916 case UI_SET_LEDBIT:
917 retval = uinput_set_bit(arg, ledbit, LED_MAX);
918 goto out;
919
920 case UI_SET_SNDBIT:
921 retval = uinput_set_bit(arg, sndbit, SND_MAX);
922 goto out;
923
924 case UI_SET_FFBIT:
925 retval = uinput_set_bit(arg, ffbit, FF_MAX);
926 goto out;
927
928 case UI_SET_SWBIT:
929 retval = uinput_set_bit(arg, swbit, SW_MAX);
930 goto out;
931
932 case UI_SET_PROPBIT:
933 retval = uinput_set_bit(arg, propbit, INPUT_PROP_MAX);
934 goto out;
935
936 case UI_SET_PHYS:
937 if (udev->state == UIST_CREATED) {
938 retval = -EINVAL;
939 goto out;
940 }
941
942 phys = strndup_user(p, 1024);
943 if (IS_ERR(phys)) {
944 retval = PTR_ERR(phys);
945 goto out;
946 }
947
948 kfree(udev->dev->phys);
949 udev->dev->phys = phys;
950 goto out;
951
952 case UI_BEGIN_FF_UPLOAD:
953 retval = uinput_ff_upload_from_user(p, &ff_up);
954 if (retval)
955 goto out;
956
957 req = uinput_request_find(udev, ff_up.request_id);
958 if (!req || req->code != UI_FF_UPLOAD ||
959 !req->u.upload.effect) {
960 retval = -EINVAL;
961 goto out;
962 }
963
964 ff_up.retval = 0;
965 ff_up.effect = *req->u.upload.effect;
966 if (req->u.upload.old)
967 ff_up.old = *req->u.upload.old;
968 else
969 memset(&ff_up.old, 0, sizeof(struct ff_effect));
970
971 retval = uinput_ff_upload_to_user(p, &ff_up);
972 goto out;
973
974 case UI_BEGIN_FF_ERASE:
975 if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
976 retval = -EFAULT;
977 goto out;
978 }
979
980 req = uinput_request_find(udev, ff_erase.request_id);
981 if (!req || req->code != UI_FF_ERASE) {
982 retval = -EINVAL;
983 goto out;
984 }
985
986 ff_erase.retval = 0;
987 ff_erase.effect_id = req->u.effect_id;
988 if (copy_to_user(p, &ff_erase, sizeof(ff_erase))) {
989 retval = -EFAULT;
990 goto out;
991 }
992
993 goto out;
994
995 case UI_END_FF_UPLOAD:
996 retval = uinput_ff_upload_from_user(p, &ff_up);
997 if (retval)
998 goto out;
999
1000 req = uinput_request_find(udev, ff_up.request_id);
1001 if (!req || req->code != UI_FF_UPLOAD ||
1002 !req->u.upload.effect) {
1003 retval = -EINVAL;
1004 goto out;
1005 }
1006
1007 req->retval = ff_up.retval;
1008 complete(&req->done);
1009 goto out;
1010
1011 case UI_END_FF_ERASE:
1012 if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) {
1013 retval = -EFAULT;
1014 goto out;
1015 }
1016
1017 req = uinput_request_find(udev, ff_erase.request_id);
1018 if (!req || req->code != UI_FF_ERASE) {
1019 retval = -EINVAL;
1020 goto out;
1021 }
1022
1023 req->retval = ff_erase.retval;
1024 complete(&req->done);
1025 goto out;
1026 }
1027
1028 size = _IOC_SIZE(cmd);
1029
1030 /* Now check variable-length commands */
1031 switch (cmd & ~IOCSIZE_MASK) {
1032 case UI_GET_SYSNAME(0):
1033 if (udev->state != UIST_CREATED) {
1034 retval = -ENOENT;
1035 goto out;
1036 }
1037 name = dev_name(&udev->dev->dev);
1038 retval = uinput_str_to_user(p, name, size);
1039 goto out;
1040
1041 case UI_ABS_SETUP & ~IOCSIZE_MASK:
1042 retval = uinput_abs_setup(udev, p, size);
1043 goto out;
1044 }
1045
1046 retval = -EINVAL;
1047 out:
1048 mutex_unlock(&udev->mutex);
1049 return retval;
1050}
1051
1052static long uinput_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
1053{
1054 return uinput_ioctl_handler(file, cmd, arg, (void __user *)arg);
1055}
1056
1057#ifdef CONFIG_COMPAT
1058
1059/*
1060 * These IOCTLs change their size and thus their numbers between
1061 * 32 and 64 bits.
1062 */
1063#define UI_SET_PHYS_COMPAT \
1064 _IOW(UINPUT_IOCTL_BASE, 108, compat_uptr_t)
1065#define UI_BEGIN_FF_UPLOAD_COMPAT \
1066 _IOWR(UINPUT_IOCTL_BASE, 200, struct uinput_ff_upload_compat)
1067#define UI_END_FF_UPLOAD_COMPAT \
1068 _IOW(UINPUT_IOCTL_BASE, 201, struct uinput_ff_upload_compat)
1069
1070static long uinput_compat_ioctl(struct file *file,
1071 unsigned int cmd, unsigned long arg)
1072{
1073 switch (cmd) {
1074 case UI_SET_PHYS_COMPAT:
1075 cmd = UI_SET_PHYS;
1076 break;
1077 case UI_BEGIN_FF_UPLOAD_COMPAT:
1078 cmd = UI_BEGIN_FF_UPLOAD;
1079 break;
1080 case UI_END_FF_UPLOAD_COMPAT:
1081 cmd = UI_END_FF_UPLOAD;
1082 break;
1083 }
1084
1085 return uinput_ioctl_handler(file, cmd, arg, compat_ptr(arg));
1086}
1087#endif
1088
1089static const struct file_operations uinput_fops = {
1090 .owner = THIS_MODULE,
1091 .open = uinput_open,
1092 .release = uinput_release,
1093 .read = uinput_read,
1094 .write = uinput_write,
1095 .poll = uinput_poll,
1096 .unlocked_ioctl = uinput_ioctl,
1097#ifdef CONFIG_COMPAT
1098 .compat_ioctl = uinput_compat_ioctl,
1099#endif
1100 .llseek = no_llseek,
1101};
1102
1103static struct miscdevice uinput_misc = {
1104 .fops = &uinput_fops,
1105 .minor = UINPUT_MINOR,
1106 .name = UINPUT_NAME,
1107};
1108module_misc_device(uinput_misc);
1109
1110MODULE_ALIAS_MISCDEV(UINPUT_MINOR);
1111MODULE_ALIAS("devname:" UINPUT_NAME);
1112
1113MODULE_AUTHOR("Aristeu Sergio Rozanski Filho");
1114MODULE_DESCRIPTION("User level driver support for input subsystem");
1115MODULE_LICENSE("GPL");