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 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 __poll_t mask = EPOLLOUT | EPOLLWRNORM; /* uinput is always writable */ 711 712 poll_wait(file, &udev->waitq, wait); 713 714 if (udev->head != udev->tail) 715 mask |= EPOLLIN | EPOLLRDNORM; 716 717 return mask; 718} 719 720static int uinput_release(struct inode *inode, struct file *file) 721{ 722 struct uinput_device *udev = file->private_data; 723 724 uinput_destroy_device(udev); 725 kfree(udev); 726 727 return 0; 728} 729 730#ifdef CONFIG_COMPAT 731struct uinput_ff_upload_compat { 732 __u32 request_id; 733 __s32 retval; 734 struct ff_effect_compat effect; 735 struct ff_effect_compat old; 736}; 737 738static int uinput_ff_upload_to_user(char __user *buffer, 739 const struct uinput_ff_upload *ff_up) 740{ 741 if (in_compat_syscall()) { 742 struct uinput_ff_upload_compat ff_up_compat; 743 744 ff_up_compat.request_id = ff_up->request_id; 745 ff_up_compat.retval = ff_up->retval; 746 /* 747 * It so happens that the pointer that gives us the trouble 748 * is the last field in the structure. Since we don't support 749 * custom waveforms in uinput anyway we can just copy the whole 750 * thing (to the compat size) and ignore the pointer. 751 */ 752 memcpy(&ff_up_compat.effect, &ff_up->effect, 753 sizeof(struct ff_effect_compat)); 754 memcpy(&ff_up_compat.old, &ff_up->old, 755 sizeof(struct ff_effect_compat)); 756 757 if (copy_to_user(buffer, &ff_up_compat, 758 sizeof(struct uinput_ff_upload_compat))) 759 return -EFAULT; 760 } else { 761 if (copy_to_user(buffer, ff_up, 762 sizeof(struct uinput_ff_upload))) 763 return -EFAULT; 764 } 765 766 return 0; 767} 768 769static int uinput_ff_upload_from_user(const char __user *buffer, 770 struct uinput_ff_upload *ff_up) 771{ 772 if (in_compat_syscall()) { 773 struct uinput_ff_upload_compat ff_up_compat; 774 775 if (copy_from_user(&ff_up_compat, buffer, 776 sizeof(struct uinput_ff_upload_compat))) 777 return -EFAULT; 778 779 ff_up->request_id = ff_up_compat.request_id; 780 ff_up->retval = ff_up_compat.retval; 781 memcpy(&ff_up->effect, &ff_up_compat.effect, 782 sizeof(struct ff_effect_compat)); 783 memcpy(&ff_up->old, &ff_up_compat.old, 784 sizeof(struct ff_effect_compat)); 785 786 } else { 787 if (copy_from_user(ff_up, buffer, 788 sizeof(struct uinput_ff_upload))) 789 return -EFAULT; 790 } 791 792 return 0; 793} 794 795#else 796 797static int uinput_ff_upload_to_user(char __user *buffer, 798 const struct uinput_ff_upload *ff_up) 799{ 800 if (copy_to_user(buffer, ff_up, sizeof(struct uinput_ff_upload))) 801 return -EFAULT; 802 803 return 0; 804} 805 806static int uinput_ff_upload_from_user(const char __user *buffer, 807 struct uinput_ff_upload *ff_up) 808{ 809 if (copy_from_user(ff_up, buffer, sizeof(struct uinput_ff_upload))) 810 return -EFAULT; 811 812 return 0; 813} 814 815#endif 816 817#define uinput_set_bit(_arg, _bit, _max) \ 818({ \ 819 int __ret = 0; \ 820 if (udev->state == UIST_CREATED) \ 821 __ret = -EINVAL; \ 822 else if ((_arg) > (_max)) \ 823 __ret = -EINVAL; \ 824 else set_bit((_arg), udev->dev->_bit); \ 825 __ret; \ 826}) 827 828static int uinput_str_to_user(void __user *dest, const char *str, 829 unsigned int maxlen) 830{ 831 char __user *p = dest; 832 int len, ret; 833 834 if (!str) 835 return -ENOENT; 836 837 if (maxlen == 0) 838 return -EINVAL; 839 840 len = strlen(str) + 1; 841 if (len > maxlen) 842 len = maxlen; 843 844 ret = copy_to_user(p, str, len); 845 if (ret) 846 return -EFAULT; 847 848 /* force terminating '\0' */ 849 ret = put_user(0, p + len - 1); 850 return ret ? -EFAULT : len; 851} 852 853static long uinput_ioctl_handler(struct file *file, unsigned int cmd, 854 unsigned long arg, void __user *p) 855{ 856 int retval; 857 struct uinput_device *udev = file->private_data; 858 struct uinput_ff_upload ff_up; 859 struct uinput_ff_erase ff_erase; 860 struct uinput_request *req; 861 char *phys; 862 const char *name; 863 unsigned int size; 864 865 retval = mutex_lock_interruptible(&udev->mutex); 866 if (retval) 867 return retval; 868 869 if (!udev->dev) { 870 udev->dev = input_allocate_device(); 871 if (!udev->dev) { 872 retval = -ENOMEM; 873 goto out; 874 } 875 } 876 877 switch (cmd) { 878 case UI_GET_VERSION: 879 if (put_user(UINPUT_VERSION, (unsigned int __user *)p)) 880 retval = -EFAULT; 881 goto out; 882 883 case UI_DEV_CREATE: 884 retval = uinput_create_device(udev); 885 goto out; 886 887 case UI_DEV_DESTROY: 888 uinput_destroy_device(udev); 889 goto out; 890 891 case UI_DEV_SETUP: 892 retval = uinput_dev_setup(udev, p); 893 goto out; 894 895 /* UI_ABS_SETUP is handled in the variable size ioctls */ 896 897 case UI_SET_EVBIT: 898 retval = uinput_set_bit(arg, evbit, EV_MAX); 899 goto out; 900 901 case UI_SET_KEYBIT: 902 retval = uinput_set_bit(arg, keybit, KEY_MAX); 903 goto out; 904 905 case UI_SET_RELBIT: 906 retval = uinput_set_bit(arg, relbit, REL_MAX); 907 goto out; 908 909 case UI_SET_ABSBIT: 910 retval = uinput_set_bit(arg, absbit, ABS_MAX); 911 goto out; 912 913 case UI_SET_MSCBIT: 914 retval = uinput_set_bit(arg, mscbit, MSC_MAX); 915 goto out; 916 917 case UI_SET_LEDBIT: 918 retval = uinput_set_bit(arg, ledbit, LED_MAX); 919 goto out; 920 921 case UI_SET_SNDBIT: 922 retval = uinput_set_bit(arg, sndbit, SND_MAX); 923 goto out; 924 925 case UI_SET_FFBIT: 926 retval = uinput_set_bit(arg, ffbit, FF_MAX); 927 goto out; 928 929 case UI_SET_SWBIT: 930 retval = uinput_set_bit(arg, swbit, SW_MAX); 931 goto out; 932 933 case UI_SET_PROPBIT: 934 retval = uinput_set_bit(arg, propbit, INPUT_PROP_MAX); 935 goto out; 936 937 case UI_SET_PHYS: 938 if (udev->state == UIST_CREATED) { 939 retval = -EINVAL; 940 goto out; 941 } 942 943 phys = strndup_user(p, 1024); 944 if (IS_ERR(phys)) { 945 retval = PTR_ERR(phys); 946 goto out; 947 } 948 949 kfree(udev->dev->phys); 950 udev->dev->phys = phys; 951 goto out; 952 953 case UI_BEGIN_FF_UPLOAD: 954 retval = uinput_ff_upload_from_user(p, &ff_up); 955 if (retval) 956 goto out; 957 958 req = uinput_request_find(udev, ff_up.request_id); 959 if (!req || req->code != UI_FF_UPLOAD || 960 !req->u.upload.effect) { 961 retval = -EINVAL; 962 goto out; 963 } 964 965 ff_up.retval = 0; 966 ff_up.effect = *req->u.upload.effect; 967 if (req->u.upload.old) 968 ff_up.old = *req->u.upload.old; 969 else 970 memset(&ff_up.old, 0, sizeof(struct ff_effect)); 971 972 retval = uinput_ff_upload_to_user(p, &ff_up); 973 goto out; 974 975 case UI_BEGIN_FF_ERASE: 976 if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) { 977 retval = -EFAULT; 978 goto out; 979 } 980 981 req = uinput_request_find(udev, ff_erase.request_id); 982 if (!req || req->code != UI_FF_ERASE) { 983 retval = -EINVAL; 984 goto out; 985 } 986 987 ff_erase.retval = 0; 988 ff_erase.effect_id = req->u.effect_id; 989 if (copy_to_user(p, &ff_erase, sizeof(ff_erase))) { 990 retval = -EFAULT; 991 goto out; 992 } 993 994 goto out; 995 996 case UI_END_FF_UPLOAD: 997 retval = uinput_ff_upload_from_user(p, &ff_up); 998 if (retval) 999 goto out; 1000 1001 req = uinput_request_find(udev, ff_up.request_id); 1002 if (!req || req->code != UI_FF_UPLOAD || 1003 !req->u.upload.effect) { 1004 retval = -EINVAL; 1005 goto out; 1006 } 1007 1008 req->retval = ff_up.retval; 1009 complete(&req->done); 1010 goto out; 1011 1012 case UI_END_FF_ERASE: 1013 if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) { 1014 retval = -EFAULT; 1015 goto out; 1016 } 1017 1018 req = uinput_request_find(udev, ff_erase.request_id); 1019 if (!req || req->code != UI_FF_ERASE) { 1020 retval = -EINVAL; 1021 goto out; 1022 } 1023 1024 req->retval = ff_erase.retval; 1025 complete(&req->done); 1026 goto out; 1027 } 1028 1029 size = _IOC_SIZE(cmd); 1030 1031 /* Now check variable-length commands */ 1032 switch (cmd & ~IOCSIZE_MASK) { 1033 case UI_GET_SYSNAME(0): 1034 if (udev->state != UIST_CREATED) { 1035 retval = -ENOENT; 1036 goto out; 1037 } 1038 name = dev_name(&udev->dev->dev); 1039 retval = uinput_str_to_user(p, name, size); 1040 goto out; 1041 1042 case UI_ABS_SETUP & ~IOCSIZE_MASK: 1043 retval = uinput_abs_setup(udev, p, size); 1044 goto out; 1045 } 1046 1047 retval = -EINVAL; 1048 out: 1049 mutex_unlock(&udev->mutex); 1050 return retval; 1051} 1052 1053static long uinput_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 1054{ 1055 return uinput_ioctl_handler(file, cmd, arg, (void __user *)arg); 1056} 1057 1058#ifdef CONFIG_COMPAT 1059 1060/* 1061 * These IOCTLs change their size and thus their numbers between 1062 * 32 and 64 bits. 1063 */ 1064#define UI_SET_PHYS_COMPAT \ 1065 _IOW(UINPUT_IOCTL_BASE, 108, compat_uptr_t) 1066#define UI_BEGIN_FF_UPLOAD_COMPAT \ 1067 _IOWR(UINPUT_IOCTL_BASE, 200, struct uinput_ff_upload_compat) 1068#define UI_END_FF_UPLOAD_COMPAT \ 1069 _IOW(UINPUT_IOCTL_BASE, 201, struct uinput_ff_upload_compat) 1070 1071static long uinput_compat_ioctl(struct file *file, 1072 unsigned int cmd, unsigned long arg) 1073{ 1074 switch (cmd) { 1075 case UI_SET_PHYS_COMPAT: 1076 cmd = UI_SET_PHYS; 1077 break; 1078 case UI_BEGIN_FF_UPLOAD_COMPAT: 1079 cmd = UI_BEGIN_FF_UPLOAD; 1080 break; 1081 case UI_END_FF_UPLOAD_COMPAT: 1082 cmd = UI_END_FF_UPLOAD; 1083 break; 1084 } 1085 1086 return uinput_ioctl_handler(file, cmd, arg, compat_ptr(arg)); 1087} 1088#endif 1089 1090static const struct file_operations uinput_fops = { 1091 .owner = THIS_MODULE, 1092 .open = uinput_open, 1093 .release = uinput_release, 1094 .read = uinput_read, 1095 .write = uinput_write, 1096 .poll = uinput_poll, 1097 .unlocked_ioctl = uinput_ioctl, 1098#ifdef CONFIG_COMPAT 1099 .compat_ioctl = uinput_compat_ioctl, 1100#endif 1101 .llseek = no_llseek, 1102}; 1103 1104static struct miscdevice uinput_misc = { 1105 .fops = &uinput_fops, 1106 .minor = UINPUT_MINOR, 1107 .name = UINPUT_NAME, 1108}; 1109module_misc_device(uinput_misc); 1110 1111MODULE_ALIAS_MISCDEV(UINPUT_MINOR); 1112MODULE_ALIAS("devname:" UINPUT_NAME); 1113 1114MODULE_AUTHOR("Aristeu Sergio Rozanski Filho"); 1115MODULE_DESCRIPTION("User level driver support for input subsystem"); 1116MODULE_LICENSE("GPL"); 1117