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/lockdep.h> 29 #include <linux/miscdevice.h> 30 #include <linux/overflow.h> 31 #include <linux/spinlock.h> 32 #include <linux/input/mt.h> 33 #include "../input-compat.h" 34 35 #define UINPUT_NAME "uinput" 36 #define UINPUT_BUFFER_SIZE 16 37 #define UINPUT_NUM_REQUESTS 16 38 #define UINPUT_TIMESTAMP_ALLOWED_OFFSET_SECS 10 39 40 enum uinput_state { UIST_NEW_DEVICE, UIST_SETUP_COMPLETE, UIST_CREATED }; 41 42 struct uinput_request { 43 unsigned int id; 44 unsigned int code; /* UI_FF_UPLOAD, UI_FF_ERASE */ 45 46 int retval; 47 struct completion done; 48 49 union { 50 unsigned int effect_id; 51 struct { 52 struct ff_effect *effect; 53 struct ff_effect *old; 54 } upload; 55 } u; 56 }; 57 58 struct uinput_device { 59 struct input_dev *dev; 60 struct mutex mutex; 61 enum uinput_state state; 62 spinlock_t state_lock; 63 wait_queue_head_t waitq; 64 unsigned char ready; 65 unsigned char head; 66 unsigned char tail; 67 struct input_event buff[UINPUT_BUFFER_SIZE]; 68 unsigned int ff_effects_max; 69 70 struct uinput_request *requests[UINPUT_NUM_REQUESTS]; 71 wait_queue_head_t requests_waitq; 72 spinlock_t requests_lock; 73 }; 74 75 static int uinput_dev_event(struct input_dev *dev, 76 unsigned int type, unsigned int code, int value) 77 { 78 struct uinput_device *udev = input_get_drvdata(dev); 79 struct timespec64 ts; 80 81 lockdep_assert_held(&dev->event_lock); 82 83 ktime_get_ts64(&ts); 84 85 udev->buff[udev->head] = (struct input_event) { 86 .input_event_sec = ts.tv_sec, 87 .input_event_usec = ts.tv_nsec / NSEC_PER_USEC, 88 .type = type, 89 .code = code, 90 .value = value, 91 }; 92 93 udev->head = (udev->head + 1) % UINPUT_BUFFER_SIZE; 94 95 wake_up_interruptible(&udev->waitq); 96 97 return 0; 98 } 99 100 /* Atomically allocate an ID for the given request. Returns 0 on success. */ 101 static bool uinput_request_alloc_id(struct uinput_device *udev, 102 struct uinput_request *request) 103 { 104 unsigned int id; 105 bool reserved = false; 106 107 spin_lock(&udev->requests_lock); 108 109 for (id = 0; id < UINPUT_NUM_REQUESTS; id++) { 110 if (!udev->requests[id]) { 111 request->id = id; 112 udev->requests[id] = request; 113 reserved = true; 114 break; 115 } 116 } 117 118 spin_unlock(&udev->requests_lock); 119 return reserved; 120 } 121 122 static struct uinput_request *uinput_request_find(struct uinput_device *udev, 123 unsigned int id) 124 { 125 /* Find an input request, by ID. Returns NULL if the ID isn't valid. */ 126 if (id >= UINPUT_NUM_REQUESTS) 127 return NULL; 128 129 return udev->requests[id]; 130 } 131 132 static int uinput_request_reserve_slot(struct uinput_device *udev, 133 struct uinput_request *request) 134 { 135 /* Allocate slot. If none are available right away, wait. */ 136 return wait_event_interruptible(udev->requests_waitq, 137 uinput_request_alloc_id(udev, request)); 138 } 139 140 static void uinput_request_release_slot(struct uinput_device *udev, 141 unsigned int id) 142 { 143 /* Mark slot as available */ 144 spin_lock(&udev->requests_lock); 145 udev->requests[id] = NULL; 146 spin_unlock(&udev->requests_lock); 147 148 wake_up(&udev->requests_waitq); 149 } 150 151 static int uinput_request_send(struct uinput_device *udev, 152 struct uinput_request *request) 153 { 154 unsigned long flags; 155 int retval = 0; 156 157 spin_lock(&udev->state_lock); 158 159 if (udev->state != UIST_CREATED) { 160 retval = -ENODEV; 161 goto out; 162 } 163 164 /* 165 * Tell our userspace application about this new request 166 * by queueing an input event. 167 */ 168 spin_lock_irqsave(&udev->dev->event_lock, flags); 169 uinput_dev_event(udev->dev, EV_UINPUT, request->code, request->id); 170 spin_unlock_irqrestore(&udev->dev->event_lock, flags); 171 172 out: 173 spin_unlock(&udev->state_lock); 174 return retval; 175 } 176 177 static int uinput_request_submit(struct uinput_device *udev, 178 struct uinput_request *request) 179 { 180 int retval; 181 182 /* 183 * Initialize completion before allocating the request slot. 184 * Once the slot is allocated, uinput_flush_requests() may 185 * complete it at any time, so it must be initialized first. 186 */ 187 init_completion(&request->done); 188 189 retval = uinput_request_reserve_slot(udev, request); 190 if (retval) 191 return retval; 192 193 retval = uinput_request_send(udev, request); 194 if (retval) 195 goto out; 196 197 if (!wait_for_completion_timeout(&request->done, 30 * HZ)) { 198 retval = -ETIMEDOUT; 199 goto out; 200 } 201 202 retval = request->retval; 203 204 out: 205 uinput_request_release_slot(udev, request->id); 206 return retval; 207 } 208 209 /* 210 * Fail all outstanding requests so handlers don't wait for the userspace 211 * to finish processing them. 212 */ 213 static void uinput_flush_requests(struct uinput_device *udev) 214 { 215 struct uinput_request *request; 216 int i; 217 218 spin_lock(&udev->requests_lock); 219 220 for (i = 0; i < UINPUT_NUM_REQUESTS; i++) { 221 request = udev->requests[i]; 222 if (request) { 223 request->retval = -ENODEV; 224 complete(&request->done); 225 } 226 } 227 228 spin_unlock(&udev->requests_lock); 229 } 230 231 static void uinput_dev_set_gain(struct input_dev *dev, u16 gain) 232 { 233 uinput_dev_event(dev, EV_FF, FF_GAIN, gain); 234 } 235 236 static void uinput_dev_set_autocenter(struct input_dev *dev, u16 magnitude) 237 { 238 uinput_dev_event(dev, EV_FF, FF_AUTOCENTER, magnitude); 239 } 240 241 static int uinput_dev_playback(struct input_dev *dev, int effect_id, int value) 242 { 243 return uinput_dev_event(dev, EV_FF, effect_id, value); 244 } 245 246 static int uinput_dev_upload_effect(struct input_dev *dev, 247 struct ff_effect *effect, 248 struct ff_effect *old) 249 { 250 struct uinput_device *udev = input_get_drvdata(dev); 251 struct uinput_request request; 252 253 /* 254 * uinput driver does not currently support periodic effects with 255 * custom waveform since it does not have a way to pass buffer of 256 * samples (custom_data) to userspace. If ever there is a device 257 * supporting custom waveforms we would need to define an additional 258 * ioctl (UI_UPLOAD_SAMPLES) but for now we just bail out. 259 */ 260 if (effect->type == FF_PERIODIC && 261 effect->u.periodic.waveform == FF_CUSTOM) 262 return -EINVAL; 263 264 request.code = UI_FF_UPLOAD; 265 request.u.upload.effect = effect; 266 request.u.upload.old = old; 267 268 return uinput_request_submit(udev, &request); 269 } 270 271 static int uinput_dev_erase_effect(struct input_dev *dev, int effect_id) 272 { 273 struct uinput_device *udev = input_get_drvdata(dev); 274 struct uinput_request request; 275 276 if (!test_bit(EV_FF, dev->evbit)) 277 return -ENOSYS; 278 279 request.code = UI_FF_ERASE; 280 request.u.effect_id = effect_id; 281 282 return uinput_request_submit(udev, &request); 283 } 284 285 static int uinput_dev_flush(struct input_dev *dev, struct file *file) 286 { 287 /* 288 * If we are called with file == NULL that means we are tearing 289 * down the device, and therefore we can not handle FF erase 290 * requests: either we are handling UI_DEV_DESTROY (and holding 291 * the udev->mutex), or the file descriptor is closed and there is 292 * nobody on the other side anymore. 293 */ 294 return file ? input_ff_flush(dev, file) : 0; 295 } 296 297 static void uinput_destroy_device(struct uinput_device *udev) 298 { 299 const char *name, *phys; 300 struct input_dev *dev = udev->dev; 301 enum uinput_state old_state = udev->state; 302 303 /* 304 * Update state under state_lock so that concurrent 305 * uinput_request_send() sees the state change before we 306 * flush pending requests and tear down the device. 307 */ 308 spin_lock(&udev->state_lock); 309 udev->state = UIST_NEW_DEVICE; 310 spin_unlock(&udev->state_lock); 311 312 if (dev) { 313 name = dev->name; 314 phys = dev->phys; 315 if (old_state == UIST_CREATED) { 316 uinput_flush_requests(udev); 317 input_unregister_device(dev); 318 } else { 319 input_free_device(dev); 320 } 321 kfree(name); 322 kfree(phys); 323 udev->dev = NULL; 324 } 325 } 326 327 static int uinput_create_device(struct uinput_device *udev) 328 { 329 struct input_dev *dev = udev->dev; 330 int error, nslot; 331 332 if (udev->state != UIST_SETUP_COMPLETE) { 333 printk(KERN_DEBUG "%s: write device info first\n", UINPUT_NAME); 334 return -EINVAL; 335 } 336 337 if (test_bit(EV_ABS, dev->evbit)) { 338 input_alloc_absinfo(dev); 339 if (!dev->absinfo) { 340 error = -EINVAL; 341 goto fail1; 342 } 343 344 if (test_bit(ABS_MT_SLOT, dev->absbit)) { 345 nslot = input_abs_get_max(dev, ABS_MT_SLOT) + 1; 346 error = input_mt_init_slots(dev, nslot, 0); 347 if (error) 348 goto fail1; 349 } else if (test_bit(ABS_MT_POSITION_X, dev->absbit)) { 350 input_set_events_per_packet(dev, 60); 351 } 352 } 353 354 if (test_bit(EV_FF, dev->evbit) && !udev->ff_effects_max) { 355 printk(KERN_DEBUG "%s: ff_effects_max should be non-zero when FF_BIT is set\n", 356 UINPUT_NAME); 357 error = -EINVAL; 358 goto fail1; 359 } 360 361 if (udev->ff_effects_max) { 362 error = input_ff_create(dev, udev->ff_effects_max); 363 if (error) 364 goto fail1; 365 366 dev->ff->upload = uinput_dev_upload_effect; 367 dev->ff->erase = uinput_dev_erase_effect; 368 dev->ff->playback = uinput_dev_playback; 369 dev->ff->set_gain = uinput_dev_set_gain; 370 dev->ff->set_autocenter = uinput_dev_set_autocenter; 371 /* 372 * The standard input_ff_flush() implementation does 373 * not quite work for uinput as we can't reasonably 374 * handle FF requests during device teardown. 375 */ 376 dev->flush = uinput_dev_flush; 377 } 378 379 dev->event = uinput_dev_event; 380 381 input_set_drvdata(udev->dev, udev); 382 383 error = input_register_device(udev->dev); 384 if (error) 385 goto fail2; 386 387 spin_lock(&udev->state_lock); 388 udev->state = UIST_CREATED; 389 spin_unlock(&udev->state_lock); 390 391 return 0; 392 393 fail2: input_ff_destroy(dev); 394 fail1: uinput_destroy_device(udev); 395 return error; 396 } 397 398 static int uinput_open(struct inode *inode, struct file *file) 399 { 400 struct uinput_device *newdev; 401 402 newdev = kzalloc_obj(*newdev); 403 if (!newdev) 404 return -ENOMEM; 405 406 mutex_init(&newdev->mutex); 407 spin_lock_init(&newdev->state_lock); 408 spin_lock_init(&newdev->requests_lock); 409 init_waitqueue_head(&newdev->requests_waitq); 410 init_waitqueue_head(&newdev->waitq); 411 newdev->state = UIST_NEW_DEVICE; 412 413 file->private_data = newdev; 414 stream_open(inode, file); 415 416 return 0; 417 } 418 419 static int uinput_validate_absinfo(struct input_dev *dev, unsigned int code, 420 const struct input_absinfo *abs) 421 { 422 int min, max, range; 423 424 min = abs->minimum; 425 max = abs->maximum; 426 427 if ((min != 0 || max != 0) && max < min) { 428 printk(KERN_DEBUG 429 "%s: invalid abs[%02x] min:%d max:%d\n", 430 UINPUT_NAME, code, min, max); 431 return -EINVAL; 432 } 433 434 if (!check_sub_overflow(max, min, &range) && abs->flat > range) { 435 printk(KERN_DEBUG 436 "%s: abs_flat #%02x out of range: %d (min:%d/max:%d)\n", 437 UINPUT_NAME, code, abs->flat, min, max); 438 return -EINVAL; 439 } 440 441 /* 442 * Limit number of contacts to a reasonable value (100). This 443 * ensures that we need less than 2 pages for struct input_mt 444 * (we are not using in-kernel slot assignment so not going to 445 * allocate memory for the "red" table), and we should have no 446 * trouble getting this much memory. 447 */ 448 if (code == ABS_MT_SLOT && max > 99) { 449 printk(KERN_DEBUG 450 "%s: unreasonably large number of slots requested: %d\n", 451 UINPUT_NAME, max); 452 return -EINVAL; 453 } 454 455 return 0; 456 } 457 458 static int uinput_validate_absbits(struct input_dev *dev) 459 { 460 unsigned int cnt; 461 int error; 462 463 if (!test_bit(EV_ABS, dev->evbit)) 464 return 0; 465 466 /* 467 * Check if absmin/absmax/absfuzz/absflat are sane. 468 */ 469 470 for_each_set_bit(cnt, dev->absbit, ABS_CNT) { 471 if (!dev->absinfo) 472 return -EINVAL; 473 474 error = uinput_validate_absinfo(dev, cnt, &dev->absinfo[cnt]); 475 if (error) 476 return error; 477 } 478 479 return 0; 480 } 481 482 static int uinput_dev_setup(struct uinput_device *udev, 483 struct uinput_setup __user *arg) 484 { 485 struct uinput_setup setup; 486 struct input_dev *dev; 487 488 if (udev->state == UIST_CREATED) 489 return -EINVAL; 490 491 if (copy_from_user(&setup, arg, sizeof(setup))) 492 return -EFAULT; 493 494 if (!setup.name[0]) 495 return -EINVAL; 496 497 dev = udev->dev; 498 dev->id = setup.id; 499 udev->ff_effects_max = setup.ff_effects_max; 500 501 kfree(dev->name); 502 dev->name = kstrndup(setup.name, UINPUT_MAX_NAME_SIZE, GFP_KERNEL); 503 if (!dev->name) 504 return -ENOMEM; 505 506 udev->state = UIST_SETUP_COMPLETE; 507 return 0; 508 } 509 510 static int uinput_abs_setup(struct uinput_device *udev, 511 struct uinput_setup __user *arg, size_t size) 512 { 513 struct uinput_abs_setup setup = {}; 514 struct input_dev *dev; 515 int error; 516 517 if (size > sizeof(setup)) 518 return -E2BIG; 519 520 if (udev->state == UIST_CREATED) 521 return -EINVAL; 522 523 if (copy_from_user(&setup, arg, size)) 524 return -EFAULT; 525 526 if (setup.code > ABS_MAX) 527 return -ERANGE; 528 529 dev = udev->dev; 530 531 error = uinput_validate_absinfo(dev, setup.code, &setup.absinfo); 532 if (error) 533 return error; 534 535 input_alloc_absinfo(dev); 536 if (!dev->absinfo) 537 return -ENOMEM; 538 539 set_bit(setup.code, dev->absbit); 540 dev->absinfo[setup.code] = setup.absinfo; 541 return 0; 542 } 543 544 /* legacy setup via write() */ 545 static int uinput_setup_device_legacy(struct uinput_device *udev, 546 const char __user *buffer, size_t count) 547 { 548 struct uinput_user_dev *user_dev; 549 struct input_dev *dev; 550 int i; 551 int retval; 552 553 if (count != sizeof(struct uinput_user_dev)) 554 return -EINVAL; 555 556 if (!udev->dev) { 557 udev->dev = input_allocate_device(); 558 if (!udev->dev) 559 return -ENOMEM; 560 } 561 562 dev = udev->dev; 563 564 user_dev = memdup_user(buffer, sizeof(struct uinput_user_dev)); 565 if (IS_ERR(user_dev)) 566 return PTR_ERR(user_dev); 567 568 udev->ff_effects_max = user_dev->ff_effects_max; 569 570 /* Ensure name is filled in */ 571 if (!user_dev->name[0]) { 572 retval = -EINVAL; 573 goto exit; 574 } 575 576 kfree(dev->name); 577 dev->name = kstrndup(user_dev->name, UINPUT_MAX_NAME_SIZE, 578 GFP_KERNEL); 579 if (!dev->name) { 580 retval = -ENOMEM; 581 goto exit; 582 } 583 584 dev->id.bustype = user_dev->id.bustype; 585 dev->id.vendor = user_dev->id.vendor; 586 dev->id.product = user_dev->id.product; 587 dev->id.version = user_dev->id.version; 588 589 for (i = 0; i < ABS_CNT; i++) { 590 input_abs_set_max(dev, i, user_dev->absmax[i]); 591 input_abs_set_min(dev, i, user_dev->absmin[i]); 592 input_abs_set_fuzz(dev, i, user_dev->absfuzz[i]); 593 input_abs_set_flat(dev, i, user_dev->absflat[i]); 594 } 595 596 retval = uinput_validate_absbits(dev); 597 if (retval < 0) 598 goto exit; 599 600 udev->state = UIST_SETUP_COMPLETE; 601 retval = count; 602 603 exit: 604 kfree(user_dev); 605 return retval; 606 } 607 608 /* 609 * Returns true if the given timestamp is valid (i.e., if all the following 610 * conditions are satisfied), false otherwise. 611 * 1) given timestamp is positive 612 * 2) it's within the allowed offset before the current time 613 * 3) it's not in the future 614 */ 615 static bool is_valid_timestamp(const ktime_t timestamp) 616 { 617 ktime_t zero_time; 618 ktime_t current_time; 619 ktime_t min_time; 620 ktime_t offset; 621 622 zero_time = ktime_set(0, 0); 623 if (ktime_compare(zero_time, timestamp) >= 0) 624 return false; 625 626 current_time = ktime_get(); 627 offset = ktime_set(UINPUT_TIMESTAMP_ALLOWED_OFFSET_SECS, 0); 628 min_time = ktime_sub(current_time, offset); 629 630 if (ktime_after(min_time, timestamp) || ktime_after(timestamp, current_time)) 631 return false; 632 633 return true; 634 } 635 636 static ssize_t uinput_inject_events(struct uinput_device *udev, 637 const char __user *buffer, size_t count) 638 { 639 struct input_event ev; 640 size_t bytes = 0; 641 ktime_t timestamp; 642 643 if (count != 0 && count < input_event_size()) 644 return -EINVAL; 645 646 while (bytes + input_event_size() <= count) { 647 /* 648 * Note that even if some events were fetched successfully 649 * we are still going to return EFAULT instead of partial 650 * count to let userspace know that it got it's buffers 651 * all wrong. 652 */ 653 if (input_event_from_user(buffer + bytes, &ev)) 654 return -EFAULT; 655 656 timestamp = ktime_set(ev.input_event_sec, ev.input_event_usec * NSEC_PER_USEC); 657 if (is_valid_timestamp(timestamp)) 658 input_set_timestamp(udev->dev, timestamp); 659 660 input_event(udev->dev, ev.type, ev.code, ev.value); 661 bytes += input_event_size(); 662 cond_resched(); 663 } 664 665 return bytes; 666 } 667 668 static ssize_t uinput_write(struct file *file, const char __user *buffer, 669 size_t count, loff_t *ppos) 670 { 671 struct uinput_device *udev = file->private_data; 672 int retval; 673 674 if (count == 0) 675 return 0; 676 677 retval = mutex_lock_interruptible(&udev->mutex); 678 if (retval) 679 return retval; 680 681 retval = udev->state == UIST_CREATED ? 682 uinput_inject_events(udev, buffer, count) : 683 uinput_setup_device_legacy(udev, buffer, count); 684 685 mutex_unlock(&udev->mutex); 686 687 return retval; 688 } 689 690 static bool uinput_fetch_next_event(struct uinput_device *udev, 691 struct input_event *event) 692 { 693 bool have_event; 694 695 spin_lock_irq(&udev->dev->event_lock); 696 697 have_event = udev->head != udev->tail; 698 if (have_event) { 699 *event = udev->buff[udev->tail]; 700 udev->tail = (udev->tail + 1) % UINPUT_BUFFER_SIZE; 701 } 702 703 spin_unlock_irq(&udev->dev->event_lock); 704 705 return have_event; 706 } 707 708 static ssize_t uinput_events_to_user(struct uinput_device *udev, 709 char __user *buffer, size_t count) 710 { 711 struct input_event event; 712 size_t read = 0; 713 714 while (read + input_event_size() <= count && 715 uinput_fetch_next_event(udev, &event)) { 716 717 if (input_event_to_user(buffer + read, &event)) 718 return -EFAULT; 719 720 read += input_event_size(); 721 } 722 723 return read; 724 } 725 726 static ssize_t uinput_read(struct file *file, char __user *buffer, 727 size_t count, loff_t *ppos) 728 { 729 struct uinput_device *udev = file->private_data; 730 ssize_t retval; 731 732 if (count != 0 && count < input_event_size()) 733 return -EINVAL; 734 735 do { 736 retval = mutex_lock_interruptible(&udev->mutex); 737 if (retval) 738 return retval; 739 740 if (udev->state != UIST_CREATED) 741 retval = -ENODEV; 742 else if (udev->head == udev->tail && 743 (file->f_flags & O_NONBLOCK)) 744 retval = -EAGAIN; 745 else 746 retval = uinput_events_to_user(udev, buffer, count); 747 748 mutex_unlock(&udev->mutex); 749 750 if (retval || count == 0) 751 break; 752 753 if (!(file->f_flags & O_NONBLOCK)) 754 retval = wait_event_interruptible(udev->waitq, 755 udev->head != udev->tail || 756 udev->state != UIST_CREATED); 757 } while (retval == 0); 758 759 return retval; 760 } 761 762 static __poll_t uinput_poll(struct file *file, poll_table *wait) 763 { 764 struct uinput_device *udev = file->private_data; 765 __poll_t mask = EPOLLOUT | EPOLLWRNORM; /* uinput is always writable */ 766 767 poll_wait(file, &udev->waitq, wait); 768 769 if (udev->head != udev->tail) 770 mask |= EPOLLIN | EPOLLRDNORM; 771 772 return mask; 773 } 774 775 static int uinput_release(struct inode *inode, struct file *file) 776 { 777 struct uinput_device *udev = file->private_data; 778 779 uinput_destroy_device(udev); 780 kfree(udev); 781 782 return 0; 783 } 784 785 #ifdef CONFIG_COMPAT 786 struct uinput_ff_upload_compat { 787 __u32 request_id; 788 __s32 retval; 789 struct ff_effect_compat effect; 790 struct ff_effect_compat old; 791 }; 792 793 static int uinput_ff_upload_to_user(char __user *buffer, 794 const struct uinput_ff_upload *ff_up) 795 { 796 if (in_compat_syscall()) { 797 struct uinput_ff_upload_compat ff_up_compat; 798 799 memset(&ff_up_compat, 0, sizeof(ff_up_compat)); 800 ff_up_compat.request_id = ff_up->request_id; 801 ff_up_compat.retval = ff_up->retval; 802 /* 803 * It so happens that the pointer that gives us the trouble 804 * is the last field in the structure. Since we don't support 805 * custom waveforms in uinput anyway we can just copy the whole 806 * thing (to the compat size) and ignore the pointer. 807 */ 808 memcpy(&ff_up_compat.effect, &ff_up->effect, 809 sizeof(struct ff_effect_compat)); 810 memcpy(&ff_up_compat.old, &ff_up->old, 811 sizeof(struct ff_effect_compat)); 812 813 if (copy_to_user(buffer, &ff_up_compat, 814 sizeof(struct uinput_ff_upload_compat))) 815 return -EFAULT; 816 } else { 817 if (copy_to_user(buffer, ff_up, 818 sizeof(struct uinput_ff_upload))) 819 return -EFAULT; 820 } 821 822 return 0; 823 } 824 825 static int uinput_ff_upload_from_user(const char __user *buffer, 826 struct uinput_ff_upload *ff_up) 827 { 828 if (in_compat_syscall()) { 829 struct uinput_ff_upload_compat ff_up_compat; 830 831 if (copy_from_user(&ff_up_compat, buffer, 832 sizeof(struct uinput_ff_upload_compat))) 833 return -EFAULT; 834 835 ff_up->request_id = ff_up_compat.request_id; 836 ff_up->retval = ff_up_compat.retval; 837 memcpy(&ff_up->effect, &ff_up_compat.effect, 838 sizeof(struct ff_effect_compat)); 839 memcpy(&ff_up->old, &ff_up_compat.old, 840 sizeof(struct ff_effect_compat)); 841 842 } else { 843 if (copy_from_user(ff_up, buffer, 844 sizeof(struct uinput_ff_upload))) 845 return -EFAULT; 846 } 847 848 return 0; 849 } 850 851 #else 852 853 static int uinput_ff_upload_to_user(char __user *buffer, 854 const struct uinput_ff_upload *ff_up) 855 { 856 if (copy_to_user(buffer, ff_up, sizeof(struct uinput_ff_upload))) 857 return -EFAULT; 858 859 return 0; 860 } 861 862 static int uinput_ff_upload_from_user(const char __user *buffer, 863 struct uinput_ff_upload *ff_up) 864 { 865 if (copy_from_user(ff_up, buffer, sizeof(struct uinput_ff_upload))) 866 return -EFAULT; 867 868 return 0; 869 } 870 871 #endif 872 873 #define uinput_set_bit(_arg, _bit, _max) \ 874 ({ \ 875 int __ret = 0; \ 876 if (udev->state == UIST_CREATED) \ 877 __ret = -EINVAL; \ 878 else if ((_arg) > (_max)) \ 879 __ret = -EINVAL; \ 880 else set_bit((_arg), udev->dev->_bit); \ 881 __ret; \ 882 }) 883 884 static int uinput_str_to_user(void __user *dest, const char *str, 885 unsigned int maxlen) 886 { 887 char __user *p = dest; 888 int len, ret; 889 890 if (!str) 891 return -ENOENT; 892 893 if (maxlen == 0) 894 return -EINVAL; 895 896 len = strlen(str) + 1; 897 if (len > maxlen) 898 len = maxlen; 899 900 ret = copy_to_user(p, str, len); 901 if (ret) 902 return -EFAULT; 903 904 /* force terminating '\0' */ 905 ret = put_user(0, p + len - 1); 906 return ret ? -EFAULT : len; 907 } 908 909 static long uinput_ioctl_handler(struct file *file, unsigned int cmd, 910 unsigned long arg, void __user *p) 911 { 912 int retval; 913 struct uinput_device *udev = file->private_data; 914 struct uinput_ff_upload ff_up; 915 struct uinput_ff_erase ff_erase; 916 struct uinput_request *req; 917 char *phys; 918 const char *name; 919 unsigned int size; 920 921 retval = mutex_lock_interruptible(&udev->mutex); 922 if (retval) 923 return retval; 924 925 if (!udev->dev) { 926 udev->dev = input_allocate_device(); 927 if (!udev->dev) { 928 retval = -ENOMEM; 929 goto out; 930 } 931 } 932 933 switch (cmd) { 934 case UI_GET_VERSION: 935 if (put_user(UINPUT_VERSION, (unsigned int __user *)p)) 936 retval = -EFAULT; 937 goto out; 938 939 case UI_DEV_CREATE: 940 retval = uinput_create_device(udev); 941 goto out; 942 943 case UI_DEV_DESTROY: 944 uinput_destroy_device(udev); 945 goto out; 946 947 case UI_DEV_SETUP: 948 retval = uinput_dev_setup(udev, p); 949 goto out; 950 951 /* UI_ABS_SETUP is handled in the variable size ioctls */ 952 953 case UI_SET_EVBIT: 954 retval = uinput_set_bit(arg, evbit, EV_MAX); 955 goto out; 956 957 case UI_SET_KEYBIT: 958 retval = uinput_set_bit(arg, keybit, KEY_MAX); 959 goto out; 960 961 case UI_SET_RELBIT: 962 retval = uinput_set_bit(arg, relbit, REL_MAX); 963 goto out; 964 965 case UI_SET_ABSBIT: 966 retval = uinput_set_bit(arg, absbit, ABS_MAX); 967 goto out; 968 969 case UI_SET_MSCBIT: 970 retval = uinput_set_bit(arg, mscbit, MSC_MAX); 971 goto out; 972 973 case UI_SET_LEDBIT: 974 retval = uinput_set_bit(arg, ledbit, LED_MAX); 975 goto out; 976 977 case UI_SET_SNDBIT: 978 retval = uinput_set_bit(arg, sndbit, SND_MAX); 979 goto out; 980 981 case UI_SET_FFBIT: 982 retval = uinput_set_bit(arg, ffbit, FF_MAX); 983 goto out; 984 985 case UI_SET_SWBIT: 986 retval = uinput_set_bit(arg, swbit, SW_MAX); 987 goto out; 988 989 case UI_SET_PROPBIT: 990 retval = uinput_set_bit(arg, propbit, INPUT_PROP_MAX); 991 goto out; 992 993 case UI_SET_PHYS: 994 if (udev->state == UIST_CREATED) { 995 retval = -EINVAL; 996 goto out; 997 } 998 999 phys = strndup_user(p, 1024); 1000 if (IS_ERR(phys)) { 1001 retval = PTR_ERR(phys); 1002 goto out; 1003 } 1004 1005 kfree(udev->dev->phys); 1006 udev->dev->phys = phys; 1007 goto out; 1008 1009 case UI_BEGIN_FF_UPLOAD: 1010 retval = uinput_ff_upload_from_user(p, &ff_up); 1011 if (retval) 1012 goto out; 1013 1014 req = uinput_request_find(udev, ff_up.request_id); 1015 if (!req || req->code != UI_FF_UPLOAD || 1016 !req->u.upload.effect) { 1017 retval = -EINVAL; 1018 goto out; 1019 } 1020 1021 ff_up.retval = 0; 1022 ff_up.effect = *req->u.upload.effect; 1023 if (req->u.upload.old) 1024 ff_up.old = *req->u.upload.old; 1025 else 1026 memset(&ff_up.old, 0, sizeof(struct ff_effect)); 1027 1028 retval = uinput_ff_upload_to_user(p, &ff_up); 1029 goto out; 1030 1031 case UI_BEGIN_FF_ERASE: 1032 if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) { 1033 retval = -EFAULT; 1034 goto out; 1035 } 1036 1037 req = uinput_request_find(udev, ff_erase.request_id); 1038 if (!req || req->code != UI_FF_ERASE) { 1039 retval = -EINVAL; 1040 goto out; 1041 } 1042 1043 ff_erase.retval = 0; 1044 ff_erase.effect_id = req->u.effect_id; 1045 if (copy_to_user(p, &ff_erase, sizeof(ff_erase))) { 1046 retval = -EFAULT; 1047 goto out; 1048 } 1049 1050 goto out; 1051 1052 case UI_END_FF_UPLOAD: 1053 retval = uinput_ff_upload_from_user(p, &ff_up); 1054 if (retval) 1055 goto out; 1056 1057 req = uinput_request_find(udev, ff_up.request_id); 1058 if (!req || req->code != UI_FF_UPLOAD || 1059 !req->u.upload.effect) { 1060 retval = -EINVAL; 1061 goto out; 1062 } 1063 1064 req->retval = ff_up.retval; 1065 complete(&req->done); 1066 goto out; 1067 1068 case UI_END_FF_ERASE: 1069 if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) { 1070 retval = -EFAULT; 1071 goto out; 1072 } 1073 1074 req = uinput_request_find(udev, ff_erase.request_id); 1075 if (!req || req->code != UI_FF_ERASE) { 1076 retval = -EINVAL; 1077 goto out; 1078 } 1079 1080 req->retval = ff_erase.retval; 1081 complete(&req->done); 1082 goto out; 1083 } 1084 1085 size = _IOC_SIZE(cmd); 1086 1087 /* Now check variable-length commands */ 1088 switch (cmd & ~IOCSIZE_MASK) { 1089 case UI_GET_SYSNAME(0): 1090 if (udev->state != UIST_CREATED) { 1091 retval = -ENOENT; 1092 goto out; 1093 } 1094 name = dev_name(&udev->dev->dev); 1095 retval = uinput_str_to_user(p, name, size); 1096 goto out; 1097 1098 case UI_ABS_SETUP & ~IOCSIZE_MASK: 1099 retval = uinput_abs_setup(udev, p, size); 1100 goto out; 1101 } 1102 1103 retval = -EINVAL; 1104 out: 1105 mutex_unlock(&udev->mutex); 1106 return retval; 1107 } 1108 1109 static long uinput_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 1110 { 1111 return uinput_ioctl_handler(file, cmd, arg, (void __user *)arg); 1112 } 1113 1114 #ifdef CONFIG_COMPAT 1115 1116 /* 1117 * These IOCTLs change their size and thus their numbers between 1118 * 32 and 64 bits. 1119 */ 1120 #define UI_SET_PHYS_COMPAT \ 1121 _IOW(UINPUT_IOCTL_BASE, 108, compat_uptr_t) 1122 #define UI_BEGIN_FF_UPLOAD_COMPAT \ 1123 _IOWR(UINPUT_IOCTL_BASE, 200, struct uinput_ff_upload_compat) 1124 #define UI_END_FF_UPLOAD_COMPAT \ 1125 _IOW(UINPUT_IOCTL_BASE, 201, struct uinput_ff_upload_compat) 1126 1127 static long uinput_compat_ioctl(struct file *file, 1128 unsigned int cmd, unsigned long arg) 1129 { 1130 switch (cmd) { 1131 case UI_SET_PHYS_COMPAT: 1132 cmd = UI_SET_PHYS; 1133 break; 1134 case UI_BEGIN_FF_UPLOAD_COMPAT: 1135 cmd = UI_BEGIN_FF_UPLOAD; 1136 break; 1137 case UI_END_FF_UPLOAD_COMPAT: 1138 cmd = UI_END_FF_UPLOAD; 1139 break; 1140 } 1141 1142 return uinput_ioctl_handler(file, cmd, arg, compat_ptr(arg)); 1143 } 1144 #endif 1145 1146 static const struct file_operations uinput_fops = { 1147 .owner = THIS_MODULE, 1148 .open = uinput_open, 1149 .release = uinput_release, 1150 .read = uinput_read, 1151 .write = uinput_write, 1152 .poll = uinput_poll, 1153 .unlocked_ioctl = uinput_ioctl, 1154 #ifdef CONFIG_COMPAT 1155 .compat_ioctl = uinput_compat_ioctl, 1156 #endif 1157 }; 1158 1159 static struct miscdevice uinput_misc = { 1160 .fops = &uinput_fops, 1161 .minor = UINPUT_MINOR, 1162 .name = UINPUT_NAME, 1163 }; 1164 module_misc_device(uinput_misc); 1165 1166 MODULE_ALIAS_MISCDEV(UINPUT_MINOR); 1167 MODULE_ALIAS("devname:" UINPUT_NAME); 1168 1169 MODULE_AUTHOR("Aristeu Sergio Rozanski Filho"); 1170 MODULE_DESCRIPTION("User level driver support for input subsystem"); 1171 MODULE_LICENSE("GPL"); 1172