1// 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#define UINPUT_TIMESTAMP_ALLOWED_OFFSET_SECS 10 37 38enum uinput_state { UIST_NEW_DEVICE, UIST_SETUP_COMPLETE, UIST_CREATED }; 39 40struct uinput_request { 41 unsigned int id; 42 unsigned int code; /* UI_FF_UPLOAD, UI_FF_ERASE */ 43 44 int retval; 45 struct completion done; 46 47 union { 48 unsigned int effect_id; 49 struct { 50 struct ff_effect *effect; 51 struct ff_effect *old; 52 } upload; 53 } u; 54}; 55 56struct uinput_device { 57 struct input_dev *dev; 58 struct mutex mutex; 59 enum uinput_state state; 60 wait_queue_head_t waitq; 61 unsigned char ready; 62 unsigned char head; 63 unsigned char tail; 64 struct input_event buff[UINPUT_BUFFER_SIZE]; 65 unsigned int ff_effects_max; 66 67 struct uinput_request *requests[UINPUT_NUM_REQUESTS]; 68 wait_queue_head_t requests_waitq; 69 spinlock_t requests_lock; 70}; 71 72static int uinput_dev_event(struct input_dev *dev, 73 unsigned int type, unsigned int code, int value) 74{ 75 struct uinput_device *udev = input_get_drvdata(dev); 76 struct timespec64 ts; 77 78 ktime_get_ts64(&ts); 79 80 udev->buff[udev->head] = (struct input_event) { 81 .input_event_sec = ts.tv_sec, 82 .input_event_usec = ts.tv_nsec / NSEC_PER_USEC, 83 .type = type, 84 .code = code, 85 .value = value, 86 }; 87 88 udev->head = (udev->head + 1) % UINPUT_BUFFER_SIZE; 89 90 wake_up_interruptible(&udev->waitq); 91 92 return 0; 93} 94 95/* Atomically allocate an ID for the given request. Returns 0 on success. */ 96static bool uinput_request_alloc_id(struct uinput_device *udev, 97 struct uinput_request *request) 98{ 99 unsigned int id; 100 bool reserved = false; 101 102 spin_lock(&udev->requests_lock); 103 104 for (id = 0; id < UINPUT_NUM_REQUESTS; id++) { 105 if (!udev->requests[id]) { 106 request->id = id; 107 udev->requests[id] = request; 108 reserved = true; 109 break; 110 } 111 } 112 113 spin_unlock(&udev->requests_lock); 114 return reserved; 115} 116 117static struct uinput_request *uinput_request_find(struct uinput_device *udev, 118 unsigned int id) 119{ 120 /* Find an input request, by ID. Returns NULL if the ID isn't valid. */ 121 if (id >= UINPUT_NUM_REQUESTS) 122 return NULL; 123 124 return udev->requests[id]; 125} 126 127static int uinput_request_reserve_slot(struct uinput_device *udev, 128 struct uinput_request *request) 129{ 130 /* Allocate slot. If none are available right away, wait. */ 131 return wait_event_interruptible(udev->requests_waitq, 132 uinput_request_alloc_id(udev, request)); 133} 134 135static void uinput_request_release_slot(struct uinput_device *udev, 136 unsigned int id) 137{ 138 /* Mark slot as available */ 139 spin_lock(&udev->requests_lock); 140 udev->requests[id] = NULL; 141 spin_unlock(&udev->requests_lock); 142 143 wake_up(&udev->requests_waitq); 144} 145 146static int uinput_request_send(struct uinput_device *udev, 147 struct uinput_request *request) 148{ 149 int retval; 150 151 retval = mutex_lock_interruptible(&udev->mutex); 152 if (retval) 153 return retval; 154 155 if (udev->state != UIST_CREATED) { 156 retval = -ENODEV; 157 goto out; 158 } 159 160 init_completion(&request->done); 161 162 /* 163 * Tell our userspace application about this new request 164 * by queueing an input event. 165 */ 166 uinput_dev_event(udev->dev, EV_UINPUT, request->code, request->id); 167 168 out: 169 mutex_unlock(&udev->mutex); 170 return retval; 171} 172 173static int uinput_request_submit(struct uinput_device *udev, 174 struct uinput_request *request) 175{ 176 int retval; 177 178 retval = uinput_request_reserve_slot(udev, request); 179 if (retval) 180 return retval; 181 182 retval = uinput_request_send(udev, request); 183 if (retval) 184 goto out; 185 186 if (!wait_for_completion_timeout(&request->done, 30 * HZ)) { 187 retval = -ETIMEDOUT; 188 goto out; 189 } 190 191 retval = request->retval; 192 193 out: 194 uinput_request_release_slot(udev, request->id); 195 return retval; 196} 197 198/* 199 * Fail all outstanding requests so handlers don't wait for the userspace 200 * to finish processing them. 201 */ 202static void uinput_flush_requests(struct uinput_device *udev) 203{ 204 struct uinput_request *request; 205 int i; 206 207 spin_lock(&udev->requests_lock); 208 209 for (i = 0; i < UINPUT_NUM_REQUESTS; i++) { 210 request = udev->requests[i]; 211 if (request) { 212 request->retval = -ENODEV; 213 complete(&request->done); 214 } 215 } 216 217 spin_unlock(&udev->requests_lock); 218} 219 220static void uinput_dev_set_gain(struct input_dev *dev, u16 gain) 221{ 222 uinput_dev_event(dev, EV_FF, FF_GAIN, gain); 223} 224 225static void uinput_dev_set_autocenter(struct input_dev *dev, u16 magnitude) 226{ 227 uinput_dev_event(dev, EV_FF, FF_AUTOCENTER, magnitude); 228} 229 230static int uinput_dev_playback(struct input_dev *dev, int effect_id, int value) 231{ 232 return uinput_dev_event(dev, EV_FF, effect_id, value); 233} 234 235static int uinput_dev_upload_effect(struct input_dev *dev, 236 struct ff_effect *effect, 237 struct ff_effect *old) 238{ 239 struct uinput_device *udev = input_get_drvdata(dev); 240 struct uinput_request request; 241 242 /* 243 * uinput driver does not currently support periodic effects with 244 * custom waveform since it does not have a way to pass buffer of 245 * samples (custom_data) to userspace. If ever there is a device 246 * supporting custom waveforms we would need to define an additional 247 * ioctl (UI_UPLOAD_SAMPLES) but for now we just bail out. 248 */ 249 if (effect->type == FF_PERIODIC && 250 effect->u.periodic.waveform == FF_CUSTOM) 251 return -EINVAL; 252 253 request.code = UI_FF_UPLOAD; 254 request.u.upload.effect = effect; 255 request.u.upload.old = old; 256 257 return uinput_request_submit(udev, &request); 258} 259 260static int uinput_dev_erase_effect(struct input_dev *dev, int effect_id) 261{ 262 struct uinput_device *udev = input_get_drvdata(dev); 263 struct uinput_request request; 264 265 if (!test_bit(EV_FF, dev->evbit)) 266 return -ENOSYS; 267 268 request.code = UI_FF_ERASE; 269 request.u.effect_id = effect_id; 270 271 return uinput_request_submit(udev, &request); 272} 273 274static int uinput_dev_flush(struct input_dev *dev, struct file *file) 275{ 276 /* 277 * If we are called with file == NULL that means we are tearing 278 * down the device, and therefore we can not handle FF erase 279 * requests: either we are handling UI_DEV_DESTROY (and holding 280 * the udev->mutex), or the file descriptor is closed and there is 281 * nobody on the other side anymore. 282 */ 283 return file ? input_ff_flush(dev, file) : 0; 284} 285 286static void uinput_destroy_device(struct uinput_device *udev) 287{ 288 const char *name, *phys; 289 struct input_dev *dev = udev->dev; 290 enum uinput_state old_state = udev->state; 291 292 udev->state = UIST_NEW_DEVICE; 293 294 if (dev) { 295 name = dev->name; 296 phys = dev->phys; 297 if (old_state == UIST_CREATED) { 298 uinput_flush_requests(udev); 299 input_unregister_device(dev); 300 } else { 301 input_free_device(dev); 302 } 303 kfree(name); 304 kfree(phys); 305 udev->dev = NULL; 306 } 307} 308 309static int uinput_create_device(struct uinput_device *udev) 310{ 311 struct input_dev *dev = udev->dev; 312 int error, nslot; 313 314 if (udev->state != UIST_SETUP_COMPLETE) { 315 printk(KERN_DEBUG "%s: write device info first\n", UINPUT_NAME); 316 return -EINVAL; 317 } 318 319 if (test_bit(EV_ABS, dev->evbit)) { 320 input_alloc_absinfo(dev); 321 if (!dev->absinfo) { 322 error = -EINVAL; 323 goto fail1; 324 } 325 326 if (test_bit(ABS_MT_SLOT, dev->absbit)) { 327 nslot = input_abs_get_max(dev, ABS_MT_SLOT) + 1; 328 error = input_mt_init_slots(dev, nslot, 0); 329 if (error) 330 goto fail1; 331 } else if (test_bit(ABS_MT_POSITION_X, dev->absbit)) { 332 input_set_events_per_packet(dev, 60); 333 } 334 } 335 336 if (test_bit(EV_FF, dev->evbit) && !udev->ff_effects_max) { 337 printk(KERN_DEBUG "%s: ff_effects_max should be non-zero when FF_BIT is set\n", 338 UINPUT_NAME); 339 error = -EINVAL; 340 goto fail1; 341 } 342 343 if (udev->ff_effects_max) { 344 error = input_ff_create(dev, udev->ff_effects_max); 345 if (error) 346 goto fail1; 347 348 dev->ff->upload = uinput_dev_upload_effect; 349 dev->ff->erase = uinput_dev_erase_effect; 350 dev->ff->playback = uinput_dev_playback; 351 dev->ff->set_gain = uinput_dev_set_gain; 352 dev->ff->set_autocenter = uinput_dev_set_autocenter; 353 /* 354 * The standard input_ff_flush() implementation does 355 * not quite work for uinput as we can't reasonably 356 * handle FF requests during device teardown. 357 */ 358 dev->flush = uinput_dev_flush; 359 } 360 361 dev->event = uinput_dev_event; 362 363 input_set_drvdata(udev->dev, udev); 364 365 error = input_register_device(udev->dev); 366 if (error) 367 goto fail2; 368 369 udev->state = UIST_CREATED; 370 371 return 0; 372 373 fail2: input_ff_destroy(dev); 374 fail1: uinput_destroy_device(udev); 375 return error; 376} 377 378static int uinput_open(struct inode *inode, struct file *file) 379{ 380 struct uinput_device *newdev; 381 382 newdev = kzalloc(sizeof(struct uinput_device), GFP_KERNEL); 383 if (!newdev) 384 return -ENOMEM; 385 386 mutex_init(&newdev->mutex); 387 spin_lock_init(&newdev->requests_lock); 388 init_waitqueue_head(&newdev->requests_waitq); 389 init_waitqueue_head(&newdev->waitq); 390 newdev->state = UIST_NEW_DEVICE; 391 392 file->private_data = newdev; 393 stream_open(inode, file); 394 395 return 0; 396} 397 398static int uinput_validate_absinfo(struct input_dev *dev, unsigned int code, 399 const struct input_absinfo *abs) 400{ 401 int min, max, range; 402 403 min = abs->minimum; 404 max = abs->maximum; 405 406 if ((min != 0 || max != 0) && max < min) { 407 printk(KERN_DEBUG 408 "%s: invalid abs[%02x] min:%d max:%d\n", 409 UINPUT_NAME, code, min, max); 410 return -EINVAL; 411 } 412 413 if (!check_sub_overflow(max, min, &range) && abs->flat > range) { 414 printk(KERN_DEBUG 415 "%s: abs_flat #%02x out of range: %d (min:%d/max:%d)\n", 416 UINPUT_NAME, code, abs->flat, min, max); 417 return -EINVAL; 418 } 419 420 return 0; 421} 422 423static int uinput_validate_absbits(struct input_dev *dev) 424{ 425 unsigned int cnt; 426 int error; 427 428 if (!test_bit(EV_ABS, dev->evbit)) 429 return 0; 430 431 /* 432 * Check if absmin/absmax/absfuzz/absflat are sane. 433 */ 434 435 for_each_set_bit(cnt, dev->absbit, ABS_CNT) { 436 if (!dev->absinfo) 437 return -EINVAL; 438 439 error = uinput_validate_absinfo(dev, cnt, &dev->absinfo[cnt]); 440 if (error) 441 return error; 442 } 443 444 return 0; 445} 446 447static int uinput_dev_setup(struct uinput_device *udev, 448 struct uinput_setup __user *arg) 449{ 450 struct uinput_setup setup; 451 struct input_dev *dev; 452 453 if (udev->state == UIST_CREATED) 454 return -EINVAL; 455 456 if (copy_from_user(&setup, arg, sizeof(setup))) 457 return -EFAULT; 458 459 if (!setup.name[0]) 460 return -EINVAL; 461 462 dev = udev->dev; 463 dev->id = setup.id; 464 udev->ff_effects_max = setup.ff_effects_max; 465 466 kfree(dev->name); 467 dev->name = kstrndup(setup.name, UINPUT_MAX_NAME_SIZE, GFP_KERNEL); 468 if (!dev->name) 469 return -ENOMEM; 470 471 udev->state = UIST_SETUP_COMPLETE; 472 return 0; 473} 474 475static int uinput_abs_setup(struct uinput_device *udev, 476 struct uinput_setup __user *arg, size_t size) 477{ 478 struct uinput_abs_setup setup = {}; 479 struct input_dev *dev; 480 int error; 481 482 if (size > sizeof(setup)) 483 return -E2BIG; 484 485 if (udev->state == UIST_CREATED) 486 return -EINVAL; 487 488 if (copy_from_user(&setup, arg, size)) 489 return -EFAULT; 490 491 if (setup.code > ABS_MAX) 492 return -ERANGE; 493 494 dev = udev->dev; 495 496 error = uinput_validate_absinfo(dev, setup.code, &setup.absinfo); 497 if (error) 498 return error; 499 500 input_alloc_absinfo(dev); 501 if (!dev->absinfo) 502 return -ENOMEM; 503 504 set_bit(setup.code, dev->absbit); 505 dev->absinfo[setup.code] = setup.absinfo; 506 return 0; 507} 508 509/* legacy setup via write() */ 510static int uinput_setup_device_legacy(struct uinput_device *udev, 511 const char __user *buffer, size_t count) 512{ 513 struct uinput_user_dev *user_dev; 514 struct input_dev *dev; 515 int i; 516 int retval; 517 518 if (count != sizeof(struct uinput_user_dev)) 519 return -EINVAL; 520 521 if (!udev->dev) { 522 udev->dev = input_allocate_device(); 523 if (!udev->dev) 524 return -ENOMEM; 525 } 526 527 dev = udev->dev; 528 529 user_dev = memdup_user(buffer, sizeof(struct uinput_user_dev)); 530 if (IS_ERR(user_dev)) 531 return PTR_ERR(user_dev); 532 533 udev->ff_effects_max = user_dev->ff_effects_max; 534 535 /* Ensure name is filled in */ 536 if (!user_dev->name[0]) { 537 retval = -EINVAL; 538 goto exit; 539 } 540 541 kfree(dev->name); 542 dev->name = kstrndup(user_dev->name, UINPUT_MAX_NAME_SIZE, 543 GFP_KERNEL); 544 if (!dev->name) { 545 retval = -ENOMEM; 546 goto exit; 547 } 548 549 dev->id.bustype = user_dev->id.bustype; 550 dev->id.vendor = user_dev->id.vendor; 551 dev->id.product = user_dev->id.product; 552 dev->id.version = user_dev->id.version; 553 554 for (i = 0; i < ABS_CNT; i++) { 555 input_abs_set_max(dev, i, user_dev->absmax[i]); 556 input_abs_set_min(dev, i, user_dev->absmin[i]); 557 input_abs_set_fuzz(dev, i, user_dev->absfuzz[i]); 558 input_abs_set_flat(dev, i, user_dev->absflat[i]); 559 } 560 561 retval = uinput_validate_absbits(dev); 562 if (retval < 0) 563 goto exit; 564 565 udev->state = UIST_SETUP_COMPLETE; 566 retval = count; 567 568 exit: 569 kfree(user_dev); 570 return retval; 571} 572 573/* 574 * Returns true if the given timestamp is valid (i.e., if all the following 575 * conditions are satisfied), false otherwise. 576 * 1) given timestamp is positive 577 * 2) it's within the allowed offset before the current time 578 * 3) it's not in the future 579 */ 580static bool is_valid_timestamp(const ktime_t timestamp) 581{ 582 ktime_t zero_time; 583 ktime_t current_time; 584 ktime_t min_time; 585 ktime_t offset; 586 587 zero_time = ktime_set(0, 0); 588 if (ktime_compare(zero_time, timestamp) >= 0) 589 return false; 590 591 current_time = ktime_get(); 592 offset = ktime_set(UINPUT_TIMESTAMP_ALLOWED_OFFSET_SECS, 0); 593 min_time = ktime_sub(current_time, offset); 594 595 if (ktime_after(min_time, timestamp) || ktime_after(timestamp, current_time)) 596 return false; 597 598 return true; 599} 600 601static ssize_t uinput_inject_events(struct uinput_device *udev, 602 const char __user *buffer, size_t count) 603{ 604 struct input_event ev; 605 size_t bytes = 0; 606 ktime_t timestamp; 607 608 if (count != 0 && count < input_event_size()) 609 return -EINVAL; 610 611 while (bytes + input_event_size() <= count) { 612 /* 613 * Note that even if some events were fetched successfully 614 * we are still going to return EFAULT instead of partial 615 * count to let userspace know that it got it's buffers 616 * all wrong. 617 */ 618 if (input_event_from_user(buffer + bytes, &ev)) 619 return -EFAULT; 620 621 timestamp = ktime_set(ev.input_event_sec, ev.input_event_usec * NSEC_PER_USEC); 622 if (is_valid_timestamp(timestamp)) 623 input_set_timestamp(udev->dev, timestamp); 624 625 input_event(udev->dev, ev.type, ev.code, ev.value); 626 bytes += input_event_size(); 627 cond_resched(); 628 } 629 630 return bytes; 631} 632 633static ssize_t uinput_write(struct file *file, const char __user *buffer, 634 size_t count, loff_t *ppos) 635{ 636 struct uinput_device *udev = file->private_data; 637 int retval; 638 639 if (count == 0) 640 return 0; 641 642 retval = mutex_lock_interruptible(&udev->mutex); 643 if (retval) 644 return retval; 645 646 retval = udev->state == UIST_CREATED ? 647 uinput_inject_events(udev, buffer, count) : 648 uinput_setup_device_legacy(udev, buffer, count); 649 650 mutex_unlock(&udev->mutex); 651 652 return retval; 653} 654 655static bool uinput_fetch_next_event(struct uinput_device *udev, 656 struct input_event *event) 657{ 658 bool have_event; 659 660 spin_lock_irq(&udev->dev->event_lock); 661 662 have_event = udev->head != udev->tail; 663 if (have_event) { 664 *event = udev->buff[udev->tail]; 665 udev->tail = (udev->tail + 1) % UINPUT_BUFFER_SIZE; 666 } 667 668 spin_unlock_irq(&udev->dev->event_lock); 669 670 return have_event; 671} 672 673static ssize_t uinput_events_to_user(struct uinput_device *udev, 674 char __user *buffer, size_t count) 675{ 676 struct input_event event; 677 size_t read = 0; 678 679 while (read + input_event_size() <= count && 680 uinput_fetch_next_event(udev, &event)) { 681 682 if (input_event_to_user(buffer + read, &event)) 683 return -EFAULT; 684 685 read += input_event_size(); 686 } 687 688 return read; 689} 690 691static ssize_t uinput_read(struct file *file, char __user *buffer, 692 size_t count, loff_t *ppos) 693{ 694 struct uinput_device *udev = file->private_data; 695 ssize_t retval; 696 697 if (count != 0 && count < input_event_size()) 698 return -EINVAL; 699 700 do { 701 retval = mutex_lock_interruptible(&udev->mutex); 702 if (retval) 703 return retval; 704 705 if (udev->state != UIST_CREATED) 706 retval = -ENODEV; 707 else if (udev->head == udev->tail && 708 (file->f_flags & O_NONBLOCK)) 709 retval = -EAGAIN; 710 else 711 retval = uinput_events_to_user(udev, buffer, count); 712 713 mutex_unlock(&udev->mutex); 714 715 if (retval || count == 0) 716 break; 717 718 if (!(file->f_flags & O_NONBLOCK)) 719 retval = wait_event_interruptible(udev->waitq, 720 udev->head != udev->tail || 721 udev->state != UIST_CREATED); 722 } while (retval == 0); 723 724 return retval; 725} 726 727static __poll_t uinput_poll(struct file *file, poll_table *wait) 728{ 729 struct uinput_device *udev = file->private_data; 730 __poll_t mask = EPOLLOUT | EPOLLWRNORM; /* uinput is always writable */ 731 732 poll_wait(file, &udev->waitq, wait); 733 734 if (udev->head != udev->tail) 735 mask |= EPOLLIN | EPOLLRDNORM; 736 737 return mask; 738} 739 740static int uinput_release(struct inode *inode, struct file *file) 741{ 742 struct uinput_device *udev = file->private_data; 743 744 uinput_destroy_device(udev); 745 kfree(udev); 746 747 return 0; 748} 749 750#ifdef CONFIG_COMPAT 751struct uinput_ff_upload_compat { 752 __u32 request_id; 753 __s32 retval; 754 struct ff_effect_compat effect; 755 struct ff_effect_compat old; 756}; 757 758static int uinput_ff_upload_to_user(char __user *buffer, 759 const struct uinput_ff_upload *ff_up) 760{ 761 if (in_compat_syscall()) { 762 struct uinput_ff_upload_compat ff_up_compat; 763 764 ff_up_compat.request_id = ff_up->request_id; 765 ff_up_compat.retval = ff_up->retval; 766 /* 767 * It so happens that the pointer that gives us the trouble 768 * is the last field in the structure. Since we don't support 769 * custom waveforms in uinput anyway we can just copy the whole 770 * thing (to the compat size) and ignore the pointer. 771 */ 772 memcpy(&ff_up_compat.effect, &ff_up->effect, 773 sizeof(struct ff_effect_compat)); 774 memcpy(&ff_up_compat.old, &ff_up->old, 775 sizeof(struct ff_effect_compat)); 776 777 if (copy_to_user(buffer, &ff_up_compat, 778 sizeof(struct uinput_ff_upload_compat))) 779 return -EFAULT; 780 } else { 781 if (copy_to_user(buffer, ff_up, 782 sizeof(struct uinput_ff_upload))) 783 return -EFAULT; 784 } 785 786 return 0; 787} 788 789static int uinput_ff_upload_from_user(const char __user *buffer, 790 struct uinput_ff_upload *ff_up) 791{ 792 if (in_compat_syscall()) { 793 struct uinput_ff_upload_compat ff_up_compat; 794 795 if (copy_from_user(&ff_up_compat, buffer, 796 sizeof(struct uinput_ff_upload_compat))) 797 return -EFAULT; 798 799 ff_up->request_id = ff_up_compat.request_id; 800 ff_up->retval = ff_up_compat.retval; 801 memcpy(&ff_up->effect, &ff_up_compat.effect, 802 sizeof(struct ff_effect_compat)); 803 memcpy(&ff_up->old, &ff_up_compat.old, 804 sizeof(struct ff_effect_compat)); 805 806 } else { 807 if (copy_from_user(ff_up, buffer, 808 sizeof(struct uinput_ff_upload))) 809 return -EFAULT; 810 } 811 812 return 0; 813} 814 815#else 816 817static int uinput_ff_upload_to_user(char __user *buffer, 818 const struct uinput_ff_upload *ff_up) 819{ 820 if (copy_to_user(buffer, ff_up, sizeof(struct uinput_ff_upload))) 821 return -EFAULT; 822 823 return 0; 824} 825 826static int uinput_ff_upload_from_user(const char __user *buffer, 827 struct uinput_ff_upload *ff_up) 828{ 829 if (copy_from_user(ff_up, buffer, sizeof(struct uinput_ff_upload))) 830 return -EFAULT; 831 832 return 0; 833} 834 835#endif 836 837#define uinput_set_bit(_arg, _bit, _max) \ 838({ \ 839 int __ret = 0; \ 840 if (udev->state == UIST_CREATED) \ 841 __ret = -EINVAL; \ 842 else if ((_arg) > (_max)) \ 843 __ret = -EINVAL; \ 844 else set_bit((_arg), udev->dev->_bit); \ 845 __ret; \ 846}) 847 848static int uinput_str_to_user(void __user *dest, const char *str, 849 unsigned int maxlen) 850{ 851 char __user *p = dest; 852 int len, ret; 853 854 if (!str) 855 return -ENOENT; 856 857 if (maxlen == 0) 858 return -EINVAL; 859 860 len = strlen(str) + 1; 861 if (len > maxlen) 862 len = maxlen; 863 864 ret = copy_to_user(p, str, len); 865 if (ret) 866 return -EFAULT; 867 868 /* force terminating '\0' */ 869 ret = put_user(0, p + len - 1); 870 return ret ? -EFAULT : len; 871} 872 873static long uinput_ioctl_handler(struct file *file, unsigned int cmd, 874 unsigned long arg, void __user *p) 875{ 876 int retval; 877 struct uinput_device *udev = file->private_data; 878 struct uinput_ff_upload ff_up; 879 struct uinput_ff_erase ff_erase; 880 struct uinput_request *req; 881 char *phys; 882 const char *name; 883 unsigned int size; 884 885 retval = mutex_lock_interruptible(&udev->mutex); 886 if (retval) 887 return retval; 888 889 if (!udev->dev) { 890 udev->dev = input_allocate_device(); 891 if (!udev->dev) { 892 retval = -ENOMEM; 893 goto out; 894 } 895 } 896 897 switch (cmd) { 898 case UI_GET_VERSION: 899 if (put_user(UINPUT_VERSION, (unsigned int __user *)p)) 900 retval = -EFAULT; 901 goto out; 902 903 case UI_DEV_CREATE: 904 retval = uinput_create_device(udev); 905 goto out; 906 907 case UI_DEV_DESTROY: 908 uinput_destroy_device(udev); 909 goto out; 910 911 case UI_DEV_SETUP: 912 retval = uinput_dev_setup(udev, p); 913 goto out; 914 915 /* UI_ABS_SETUP is handled in the variable size ioctls */ 916 917 case UI_SET_EVBIT: 918 retval = uinput_set_bit(arg, evbit, EV_MAX); 919 goto out; 920 921 case UI_SET_KEYBIT: 922 retval = uinput_set_bit(arg, keybit, KEY_MAX); 923 goto out; 924 925 case UI_SET_RELBIT: 926 retval = uinput_set_bit(arg, relbit, REL_MAX); 927 goto out; 928 929 case UI_SET_ABSBIT: 930 retval = uinput_set_bit(arg, absbit, ABS_MAX); 931 goto out; 932 933 case UI_SET_MSCBIT: 934 retval = uinput_set_bit(arg, mscbit, MSC_MAX); 935 goto out; 936 937 case UI_SET_LEDBIT: 938 retval = uinput_set_bit(arg, ledbit, LED_MAX); 939 goto out; 940 941 case UI_SET_SNDBIT: 942 retval = uinput_set_bit(arg, sndbit, SND_MAX); 943 goto out; 944 945 case UI_SET_FFBIT: 946 retval = uinput_set_bit(arg, ffbit, FF_MAX); 947 goto out; 948 949 case UI_SET_SWBIT: 950 retval = uinput_set_bit(arg, swbit, SW_MAX); 951 goto out; 952 953 case UI_SET_PROPBIT: 954 retval = uinput_set_bit(arg, propbit, INPUT_PROP_MAX); 955 goto out; 956 957 case UI_SET_PHYS: 958 if (udev->state == UIST_CREATED) { 959 retval = -EINVAL; 960 goto out; 961 } 962 963 phys = strndup_user(p, 1024); 964 if (IS_ERR(phys)) { 965 retval = PTR_ERR(phys); 966 goto out; 967 } 968 969 kfree(udev->dev->phys); 970 udev->dev->phys = phys; 971 goto out; 972 973 case UI_BEGIN_FF_UPLOAD: 974 retval = uinput_ff_upload_from_user(p, &ff_up); 975 if (retval) 976 goto out; 977 978 req = uinput_request_find(udev, ff_up.request_id); 979 if (!req || req->code != UI_FF_UPLOAD || 980 !req->u.upload.effect) { 981 retval = -EINVAL; 982 goto out; 983 } 984 985 ff_up.retval = 0; 986 ff_up.effect = *req->u.upload.effect; 987 if (req->u.upload.old) 988 ff_up.old = *req->u.upload.old; 989 else 990 memset(&ff_up.old, 0, sizeof(struct ff_effect)); 991 992 retval = uinput_ff_upload_to_user(p, &ff_up); 993 goto out; 994 995 case UI_BEGIN_FF_ERASE: 996 if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) { 997 retval = -EFAULT; 998 goto out; 999 } 1000 1001 req = uinput_request_find(udev, ff_erase.request_id); 1002 if (!req || req->code != UI_FF_ERASE) { 1003 retval = -EINVAL; 1004 goto out; 1005 } 1006 1007 ff_erase.retval = 0; 1008 ff_erase.effect_id = req->u.effect_id; 1009 if (copy_to_user(p, &ff_erase, sizeof(ff_erase))) { 1010 retval = -EFAULT; 1011 goto out; 1012 } 1013 1014 goto out; 1015 1016 case UI_END_FF_UPLOAD: 1017 retval = uinput_ff_upload_from_user(p, &ff_up); 1018 if (retval) 1019 goto out; 1020 1021 req = uinput_request_find(udev, ff_up.request_id); 1022 if (!req || req->code != UI_FF_UPLOAD || 1023 !req->u.upload.effect) { 1024 retval = -EINVAL; 1025 goto out; 1026 } 1027 1028 req->retval = ff_up.retval; 1029 complete(&req->done); 1030 goto out; 1031 1032 case UI_END_FF_ERASE: 1033 if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) { 1034 retval = -EFAULT; 1035 goto out; 1036 } 1037 1038 req = uinput_request_find(udev, ff_erase.request_id); 1039 if (!req || req->code != UI_FF_ERASE) { 1040 retval = -EINVAL; 1041 goto out; 1042 } 1043 1044 req->retval = ff_erase.retval; 1045 complete(&req->done); 1046 goto out; 1047 } 1048 1049 size = _IOC_SIZE(cmd); 1050 1051 /* Now check variable-length commands */ 1052 switch (cmd & ~IOCSIZE_MASK) { 1053 case UI_GET_SYSNAME(0): 1054 if (udev->state != UIST_CREATED) { 1055 retval = -ENOENT; 1056 goto out; 1057 } 1058 name = dev_name(&udev->dev->dev); 1059 retval = uinput_str_to_user(p, name, size); 1060 goto out; 1061 1062 case UI_ABS_SETUP & ~IOCSIZE_MASK: 1063 retval = uinput_abs_setup(udev, p, size); 1064 goto out; 1065 } 1066 1067 retval = -EINVAL; 1068 out: 1069 mutex_unlock(&udev->mutex); 1070 return retval; 1071} 1072 1073static long uinput_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 1074{ 1075 return uinput_ioctl_handler(file, cmd, arg, (void __user *)arg); 1076} 1077 1078#ifdef CONFIG_COMPAT 1079 1080/* 1081 * These IOCTLs change their size and thus their numbers between 1082 * 32 and 64 bits. 1083 */ 1084#define UI_SET_PHYS_COMPAT \ 1085 _IOW(UINPUT_IOCTL_BASE, 108, compat_uptr_t) 1086#define UI_BEGIN_FF_UPLOAD_COMPAT \ 1087 _IOWR(UINPUT_IOCTL_BASE, 200, struct uinput_ff_upload_compat) 1088#define UI_END_FF_UPLOAD_COMPAT \ 1089 _IOW(UINPUT_IOCTL_BASE, 201, struct uinput_ff_upload_compat) 1090 1091static long uinput_compat_ioctl(struct file *file, 1092 unsigned int cmd, unsigned long arg) 1093{ 1094 switch (cmd) { 1095 case UI_SET_PHYS_COMPAT: 1096 cmd = UI_SET_PHYS; 1097 break; 1098 case UI_BEGIN_FF_UPLOAD_COMPAT: 1099 cmd = UI_BEGIN_FF_UPLOAD; 1100 break; 1101 case UI_END_FF_UPLOAD_COMPAT: 1102 cmd = UI_END_FF_UPLOAD; 1103 break; 1104 } 1105 1106 return uinput_ioctl_handler(file, cmd, arg, compat_ptr(arg)); 1107} 1108#endif 1109 1110static const struct file_operations uinput_fops = { 1111 .owner = THIS_MODULE, 1112 .open = uinput_open, 1113 .release = uinput_release, 1114 .read = uinput_read, 1115 .write = uinput_write, 1116 .poll = uinput_poll, 1117 .unlocked_ioctl = uinput_ioctl, 1118#ifdef CONFIG_COMPAT 1119 .compat_ioctl = uinput_compat_ioctl, 1120#endif 1121 .llseek = no_llseek, 1122}; 1123 1124static struct miscdevice uinput_misc = { 1125 .fops = &uinput_fops, 1126 .minor = UINPUT_MINOR, 1127 .name = UINPUT_NAME, 1128}; 1129module_misc_device(uinput_misc); 1130 1131MODULE_ALIAS_MISCDEV(UINPUT_MINOR); 1132MODULE_ALIAS("devname:" UINPUT_NAME); 1133 1134MODULE_AUTHOR("Aristeu Sergio Rozanski Filho"); 1135MODULE_DESCRIPTION("User level driver support for input subsystem"); 1136MODULE_LICENSE("GPL"); 1137