1 /* 2 * User level driver support for input subsystem 3 * 4 * Heavily based on evdev.c by Vojtech Pavlik 5 * 6 * This program is free software; you can redistribute it and/or modify 7 * it under the terms of the GNU General Public License as published by 8 * the Free Software Foundation; either version 2 of the License, or 9 * (at your option) any later version. 10 * 11 * This program is distributed in the hope that it will be useful, 12 * but WITHOUT ANY WARRANTY; without even the implied warranty of 13 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 14 * GNU General Public License for more details. 15 * 16 * You should have received a copy of the GNU General Public License 17 * along with this program; if not, write to the Free Software 18 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 19 * 20 * Author: Aristeu Sergio Rozanski Filho <aris@cathedrallabs.org> 21 * 22 * Changes/Revisions: 23 * 0.4 01/09/2014 (Benjamin Tissoires <benjamin.tissoires@redhat.com>) 24 * - add UI_GET_SYSNAME ioctl 25 * 0.3 09/04/2006 (Anssi Hannula <anssi.hannula@gmail.com>) 26 * - updated ff support for the changes in kernel interface 27 * - added MODULE_VERSION 28 * 0.2 16/10/2004 (Micah Dowty <micah@navi.cx>) 29 * - added force feedback support 30 * - added UI_SET_PHYS 31 * 0.1 20/06/2002 32 * - first public version 33 */ 34 #include <uapi/linux/uinput.h> 35 #include <linux/poll.h> 36 #include <linux/sched.h> 37 #include <linux/slab.h> 38 #include <linux/module.h> 39 #include <linux/init.h> 40 #include <linux/fs.h> 41 #include <linux/miscdevice.h> 42 #include <linux/overflow.h> 43 #include <linux/input/mt.h> 44 #include "../input-compat.h" 45 46 #define UINPUT_NAME "uinput" 47 #define UINPUT_BUFFER_SIZE 16 48 #define UINPUT_NUM_REQUESTS 16 49 50 enum uinput_state { UIST_NEW_DEVICE, UIST_SETUP_COMPLETE, UIST_CREATED }; 51 52 struct uinput_request { 53 unsigned int id; 54 unsigned int code; /* UI_FF_UPLOAD, UI_FF_ERASE */ 55 56 int retval; 57 struct completion done; 58 59 union { 60 unsigned int effect_id; 61 struct { 62 struct ff_effect *effect; 63 struct ff_effect *old; 64 } upload; 65 } u; 66 }; 67 68 struct uinput_device { 69 struct input_dev *dev; 70 struct mutex mutex; 71 enum uinput_state state; 72 wait_queue_head_t waitq; 73 unsigned char ready; 74 unsigned char head; 75 unsigned char tail; 76 struct input_event buff[UINPUT_BUFFER_SIZE]; 77 unsigned int ff_effects_max; 78 79 struct uinput_request *requests[UINPUT_NUM_REQUESTS]; 80 wait_queue_head_t requests_waitq; 81 spinlock_t requests_lock; 82 }; 83 84 static int uinput_dev_event(struct input_dev *dev, 85 unsigned int type, unsigned int code, int value) 86 { 87 struct uinput_device *udev = input_get_drvdata(dev); 88 struct timespec64 ts; 89 90 udev->buff[udev->head].type = type; 91 udev->buff[udev->head].code = code; 92 udev->buff[udev->head].value = value; 93 ktime_get_ts64(&ts); 94 udev->buff[udev->head].input_event_sec = ts.tv_sec; 95 udev->buff[udev->head].input_event_usec = ts.tv_nsec / NSEC_PER_USEC; 96 udev->head = (udev->head + 1) % UINPUT_BUFFER_SIZE; 97 98 wake_up_interruptible(&udev->waitq); 99 100 return 0; 101 } 102 103 /* Atomically allocate an ID for the given request. Returns 0 on success. */ 104 static bool uinput_request_alloc_id(struct uinput_device *udev, 105 struct uinput_request *request) 106 { 107 unsigned int id; 108 bool reserved = false; 109 110 spin_lock(&udev->requests_lock); 111 112 for (id = 0; id < UINPUT_NUM_REQUESTS; id++) { 113 if (!udev->requests[id]) { 114 request->id = id; 115 udev->requests[id] = request; 116 reserved = true; 117 break; 118 } 119 } 120 121 spin_unlock(&udev->requests_lock); 122 return reserved; 123 } 124 125 static struct uinput_request *uinput_request_find(struct uinput_device *udev, 126 unsigned int id) 127 { 128 /* Find an input request, by ID. Returns NULL if the ID isn't valid. */ 129 if (id >= UINPUT_NUM_REQUESTS) 130 return NULL; 131 132 return udev->requests[id]; 133 } 134 135 static int uinput_request_reserve_slot(struct uinput_device *udev, 136 struct uinput_request *request) 137 { 138 /* Allocate slot. If none are available right away, wait. */ 139 return wait_event_interruptible(udev->requests_waitq, 140 uinput_request_alloc_id(udev, request)); 141 } 142 143 static void uinput_request_release_slot(struct uinput_device *udev, 144 unsigned int id) 145 { 146 /* Mark slot as available */ 147 spin_lock(&udev->requests_lock); 148 udev->requests[id] = NULL; 149 spin_unlock(&udev->requests_lock); 150 151 wake_up(&udev->requests_waitq); 152 } 153 154 static int uinput_request_send(struct uinput_device *udev, 155 struct uinput_request *request) 156 { 157 int retval; 158 159 retval = mutex_lock_interruptible(&udev->mutex); 160 if (retval) 161 return retval; 162 163 if (udev->state != UIST_CREATED) { 164 retval = -ENODEV; 165 goto out; 166 } 167 168 init_completion(&request->done); 169 170 /* 171 * Tell our userspace application about this new request 172 * by queueing an input event. 173 */ 174 uinput_dev_event(udev->dev, EV_UINPUT, request->code, request->id); 175 176 out: 177 mutex_unlock(&udev->mutex); 178 return retval; 179 } 180 181 static int uinput_request_submit(struct uinput_device *udev, 182 struct uinput_request *request) 183 { 184 int retval; 185 186 retval = uinput_request_reserve_slot(udev, request); 187 if (retval) 188 return retval; 189 190 retval = uinput_request_send(udev, request); 191 if (retval) 192 goto out; 193 194 if (!wait_for_completion_timeout(&request->done, 30 * HZ)) { 195 retval = -ETIMEDOUT; 196 goto out; 197 } 198 199 retval = request->retval; 200 201 out: 202 uinput_request_release_slot(udev, request->id); 203 return retval; 204 } 205 206 /* 207 * Fail all outstanding requests so handlers don't wait for the userspace 208 * to finish processing them. 209 */ 210 static void uinput_flush_requests(struct uinput_device *udev) 211 { 212 struct uinput_request *request; 213 int i; 214 215 spin_lock(&udev->requests_lock); 216 217 for (i = 0; i < UINPUT_NUM_REQUESTS; i++) { 218 request = udev->requests[i]; 219 if (request) { 220 request->retval = -ENODEV; 221 complete(&request->done); 222 } 223 } 224 225 spin_unlock(&udev->requests_lock); 226 } 227 228 static void uinput_dev_set_gain(struct input_dev *dev, u16 gain) 229 { 230 uinput_dev_event(dev, EV_FF, FF_GAIN, gain); 231 } 232 233 static void uinput_dev_set_autocenter(struct input_dev *dev, u16 magnitude) 234 { 235 uinput_dev_event(dev, EV_FF, FF_AUTOCENTER, magnitude); 236 } 237 238 static int uinput_dev_playback(struct input_dev *dev, int effect_id, int value) 239 { 240 return uinput_dev_event(dev, EV_FF, effect_id, value); 241 } 242 243 static int uinput_dev_upload_effect(struct input_dev *dev, 244 struct ff_effect *effect, 245 struct ff_effect *old) 246 { 247 struct uinput_device *udev = input_get_drvdata(dev); 248 struct uinput_request request; 249 250 /* 251 * uinput driver does not currently support periodic effects with 252 * custom waveform since it does not have a way to pass buffer of 253 * samples (custom_data) to userspace. If ever there is a device 254 * supporting custom waveforms we would need to define an additional 255 * ioctl (UI_UPLOAD_SAMPLES) but for now we just bail out. 256 */ 257 if (effect->type == FF_PERIODIC && 258 effect->u.periodic.waveform == FF_CUSTOM) 259 return -EINVAL; 260 261 request.code = UI_FF_UPLOAD; 262 request.u.upload.effect = effect; 263 request.u.upload.old = old; 264 265 return uinput_request_submit(udev, &request); 266 } 267 268 static int uinput_dev_erase_effect(struct input_dev *dev, int effect_id) 269 { 270 struct uinput_device *udev = input_get_drvdata(dev); 271 struct uinput_request request; 272 273 if (!test_bit(EV_FF, dev->evbit)) 274 return -ENOSYS; 275 276 request.code = UI_FF_ERASE; 277 request.u.effect_id = effect_id; 278 279 return uinput_request_submit(udev, &request); 280 } 281 282 static int uinput_dev_flush(struct input_dev *dev, struct file *file) 283 { 284 /* 285 * If we are called with file == NULL that means we are tearing 286 * down the device, and therefore we can not handle FF erase 287 * requests: either we are handling UI_DEV_DESTROY (and holding 288 * the udev->mutex), or the file descriptor is closed and there is 289 * nobody on the other side anymore. 290 */ 291 return file ? input_ff_flush(dev, file) : 0; 292 } 293 294 static void uinput_destroy_device(struct uinput_device *udev) 295 { 296 const char *name, *phys; 297 struct input_dev *dev = udev->dev; 298 enum uinput_state old_state = udev->state; 299 300 udev->state = UIST_NEW_DEVICE; 301 302 if (dev) { 303 name = dev->name; 304 phys = dev->phys; 305 if (old_state == UIST_CREATED) { 306 uinput_flush_requests(udev); 307 input_unregister_device(dev); 308 } else { 309 input_free_device(dev); 310 } 311 kfree(name); 312 kfree(phys); 313 udev->dev = NULL; 314 } 315 } 316 317 static int uinput_create_device(struct uinput_device *udev) 318 { 319 struct input_dev *dev = udev->dev; 320 int error, nslot; 321 322 if (udev->state != UIST_SETUP_COMPLETE) { 323 printk(KERN_DEBUG "%s: write device info first\n", UINPUT_NAME); 324 return -EINVAL; 325 } 326 327 if (test_bit(EV_ABS, dev->evbit)) { 328 input_alloc_absinfo(dev); 329 if (!dev->absinfo) { 330 error = -EINVAL; 331 goto fail1; 332 } 333 334 if (test_bit(ABS_MT_SLOT, dev->absbit)) { 335 nslot = input_abs_get_max(dev, ABS_MT_SLOT) + 1; 336 error = input_mt_init_slots(dev, nslot, 0); 337 if (error) 338 goto fail1; 339 } else if (test_bit(ABS_MT_POSITION_X, dev->absbit)) { 340 input_set_events_per_packet(dev, 60); 341 } 342 } 343 344 if (test_bit(EV_FF, dev->evbit) && !udev->ff_effects_max) { 345 printk(KERN_DEBUG "%s: ff_effects_max should be non-zero when FF_BIT is set\n", 346 UINPUT_NAME); 347 error = -EINVAL; 348 goto fail1; 349 } 350 351 if (udev->ff_effects_max) { 352 error = input_ff_create(dev, udev->ff_effects_max); 353 if (error) 354 goto fail1; 355 356 dev->ff->upload = uinput_dev_upload_effect; 357 dev->ff->erase = uinput_dev_erase_effect; 358 dev->ff->playback = uinput_dev_playback; 359 dev->ff->set_gain = uinput_dev_set_gain; 360 dev->ff->set_autocenter = uinput_dev_set_autocenter; 361 /* 362 * The standard input_ff_flush() implementation does 363 * not quite work for uinput as we can't reasonably 364 * handle FF requests during device teardown. 365 */ 366 dev->flush = uinput_dev_flush; 367 } 368 369 dev->event = uinput_dev_event; 370 371 input_set_drvdata(udev->dev, udev); 372 373 error = input_register_device(udev->dev); 374 if (error) 375 goto fail2; 376 377 udev->state = UIST_CREATED; 378 379 return 0; 380 381 fail2: input_ff_destroy(dev); 382 fail1: uinput_destroy_device(udev); 383 return error; 384 } 385 386 static int uinput_open(struct inode *inode, struct file *file) 387 { 388 struct uinput_device *newdev; 389 390 newdev = kzalloc(sizeof(struct uinput_device), GFP_KERNEL); 391 if (!newdev) 392 return -ENOMEM; 393 394 mutex_init(&newdev->mutex); 395 spin_lock_init(&newdev->requests_lock); 396 init_waitqueue_head(&newdev->requests_waitq); 397 init_waitqueue_head(&newdev->waitq); 398 newdev->state = UIST_NEW_DEVICE; 399 400 file->private_data = newdev; 401 stream_open(inode, file); 402 403 return 0; 404 } 405 406 static int uinput_validate_absinfo(struct input_dev *dev, unsigned int code, 407 const struct input_absinfo *abs) 408 { 409 int min, max, range; 410 411 min = abs->minimum; 412 max = abs->maximum; 413 414 if ((min != 0 || max != 0) && max < min) { 415 printk(KERN_DEBUG 416 "%s: invalid abs[%02x] min:%d max:%d\n", 417 UINPUT_NAME, code, min, max); 418 return -EINVAL; 419 } 420 421 if (!check_sub_overflow(max, min, &range) && abs->flat > range) { 422 printk(KERN_DEBUG 423 "%s: abs_flat #%02x out of range: %d (min:%d/max:%d)\n", 424 UINPUT_NAME, code, abs->flat, min, max); 425 return -EINVAL; 426 } 427 428 return 0; 429 } 430 431 static int uinput_validate_absbits(struct input_dev *dev) 432 { 433 unsigned int cnt; 434 int error; 435 436 if (!test_bit(EV_ABS, dev->evbit)) 437 return 0; 438 439 /* 440 * Check if absmin/absmax/absfuzz/absflat are sane. 441 */ 442 443 for_each_set_bit(cnt, dev->absbit, ABS_CNT) { 444 if (!dev->absinfo) 445 return -EINVAL; 446 447 error = uinput_validate_absinfo(dev, cnt, &dev->absinfo[cnt]); 448 if (error) 449 return error; 450 } 451 452 return 0; 453 } 454 455 static int uinput_dev_setup(struct uinput_device *udev, 456 struct uinput_setup __user *arg) 457 { 458 struct uinput_setup setup; 459 struct input_dev *dev; 460 461 if (udev->state == UIST_CREATED) 462 return -EINVAL; 463 464 if (copy_from_user(&setup, arg, sizeof(setup))) 465 return -EFAULT; 466 467 if (!setup.name[0]) 468 return -EINVAL; 469 470 dev = udev->dev; 471 dev->id = setup.id; 472 udev->ff_effects_max = setup.ff_effects_max; 473 474 kfree(dev->name); 475 dev->name = kstrndup(setup.name, UINPUT_MAX_NAME_SIZE, GFP_KERNEL); 476 if (!dev->name) 477 return -ENOMEM; 478 479 udev->state = UIST_SETUP_COMPLETE; 480 return 0; 481 } 482 483 static int uinput_abs_setup(struct uinput_device *udev, 484 struct uinput_setup __user *arg, size_t size) 485 { 486 struct uinput_abs_setup setup = {}; 487 struct input_dev *dev; 488 int error; 489 490 if (size > sizeof(setup)) 491 return -E2BIG; 492 493 if (udev->state == UIST_CREATED) 494 return -EINVAL; 495 496 if (copy_from_user(&setup, arg, size)) 497 return -EFAULT; 498 499 if (setup.code > ABS_MAX) 500 return -ERANGE; 501 502 dev = udev->dev; 503 504 error = uinput_validate_absinfo(dev, setup.code, &setup.absinfo); 505 if (error) 506 return error; 507 508 input_alloc_absinfo(dev); 509 if (!dev->absinfo) 510 return -ENOMEM; 511 512 set_bit(setup.code, dev->absbit); 513 dev->absinfo[setup.code] = setup.absinfo; 514 return 0; 515 } 516 517 /* legacy setup via write() */ 518 static int uinput_setup_device_legacy(struct uinput_device *udev, 519 const char __user *buffer, size_t count) 520 { 521 struct uinput_user_dev *user_dev; 522 struct input_dev *dev; 523 int i; 524 int retval; 525 526 if (count != sizeof(struct uinput_user_dev)) 527 return -EINVAL; 528 529 if (!udev->dev) { 530 udev->dev = input_allocate_device(); 531 if (!udev->dev) 532 return -ENOMEM; 533 } 534 535 dev = udev->dev; 536 537 user_dev = memdup_user(buffer, sizeof(struct uinput_user_dev)); 538 if (IS_ERR(user_dev)) 539 return PTR_ERR(user_dev); 540 541 udev->ff_effects_max = user_dev->ff_effects_max; 542 543 /* Ensure name is filled in */ 544 if (!user_dev->name[0]) { 545 retval = -EINVAL; 546 goto exit; 547 } 548 549 kfree(dev->name); 550 dev->name = kstrndup(user_dev->name, UINPUT_MAX_NAME_SIZE, 551 GFP_KERNEL); 552 if (!dev->name) { 553 retval = -ENOMEM; 554 goto exit; 555 } 556 557 dev->id.bustype = user_dev->id.bustype; 558 dev->id.vendor = user_dev->id.vendor; 559 dev->id.product = user_dev->id.product; 560 dev->id.version = user_dev->id.version; 561 562 for (i = 0; i < ABS_CNT; i++) { 563 input_abs_set_max(dev, i, user_dev->absmax[i]); 564 input_abs_set_min(dev, i, user_dev->absmin[i]); 565 input_abs_set_fuzz(dev, i, user_dev->absfuzz[i]); 566 input_abs_set_flat(dev, i, user_dev->absflat[i]); 567 } 568 569 retval = uinput_validate_absbits(dev); 570 if (retval < 0) 571 goto exit; 572 573 udev->state = UIST_SETUP_COMPLETE; 574 retval = count; 575 576 exit: 577 kfree(user_dev); 578 return retval; 579 } 580 581 static ssize_t uinput_inject_events(struct uinput_device *udev, 582 const char __user *buffer, size_t count) 583 { 584 struct input_event ev; 585 size_t bytes = 0; 586 587 if (count != 0 && count < input_event_size()) 588 return -EINVAL; 589 590 while (bytes + input_event_size() <= count) { 591 /* 592 * Note that even if some events were fetched successfully 593 * we are still going to return EFAULT instead of partial 594 * count to let userspace know that it got it's buffers 595 * all wrong. 596 */ 597 if (input_event_from_user(buffer + bytes, &ev)) 598 return -EFAULT; 599 600 input_event(udev->dev, ev.type, ev.code, ev.value); 601 bytes += input_event_size(); 602 cond_resched(); 603 } 604 605 return bytes; 606 } 607 608 static ssize_t uinput_write(struct file *file, const char __user *buffer, 609 size_t count, loff_t *ppos) 610 { 611 struct uinput_device *udev = file->private_data; 612 int retval; 613 614 if (count == 0) 615 return 0; 616 617 retval = mutex_lock_interruptible(&udev->mutex); 618 if (retval) 619 return retval; 620 621 retval = udev->state == UIST_CREATED ? 622 uinput_inject_events(udev, buffer, count) : 623 uinput_setup_device_legacy(udev, buffer, count); 624 625 mutex_unlock(&udev->mutex); 626 627 return retval; 628 } 629 630 static bool uinput_fetch_next_event(struct uinput_device *udev, 631 struct input_event *event) 632 { 633 bool have_event; 634 635 spin_lock_irq(&udev->dev->event_lock); 636 637 have_event = udev->head != udev->tail; 638 if (have_event) { 639 *event = udev->buff[udev->tail]; 640 udev->tail = (udev->tail + 1) % UINPUT_BUFFER_SIZE; 641 } 642 643 spin_unlock_irq(&udev->dev->event_lock); 644 645 return have_event; 646 } 647 648 static ssize_t uinput_events_to_user(struct uinput_device *udev, 649 char __user *buffer, size_t count) 650 { 651 struct input_event event; 652 size_t read = 0; 653 654 while (read + input_event_size() <= count && 655 uinput_fetch_next_event(udev, &event)) { 656 657 if (input_event_to_user(buffer + read, &event)) 658 return -EFAULT; 659 660 read += input_event_size(); 661 } 662 663 return read; 664 } 665 666 static ssize_t uinput_read(struct file *file, char __user *buffer, 667 size_t count, loff_t *ppos) 668 { 669 struct uinput_device *udev = file->private_data; 670 ssize_t retval; 671 672 if (count != 0 && count < input_event_size()) 673 return -EINVAL; 674 675 do { 676 retval = mutex_lock_interruptible(&udev->mutex); 677 if (retval) 678 return retval; 679 680 if (udev->state != UIST_CREATED) 681 retval = -ENODEV; 682 else if (udev->head == udev->tail && 683 (file->f_flags & O_NONBLOCK)) 684 retval = -EAGAIN; 685 else 686 retval = uinput_events_to_user(udev, buffer, count); 687 688 mutex_unlock(&udev->mutex); 689 690 if (retval || count == 0) 691 break; 692 693 if (!(file->f_flags & O_NONBLOCK)) 694 retval = wait_event_interruptible(udev->waitq, 695 udev->head != udev->tail || 696 udev->state != UIST_CREATED); 697 } while (retval == 0); 698 699 return retval; 700 } 701 702 static __poll_t uinput_poll(struct file *file, poll_table *wait) 703 { 704 struct uinput_device *udev = file->private_data; 705 706 poll_wait(file, &udev->waitq, wait); 707 708 if (udev->head != udev->tail) 709 return EPOLLIN | EPOLLRDNORM; 710 711 return 0; 712 } 713 714 static int uinput_release(struct inode *inode, struct file *file) 715 { 716 struct uinput_device *udev = file->private_data; 717 718 uinput_destroy_device(udev); 719 kfree(udev); 720 721 return 0; 722 } 723 724 #ifdef CONFIG_COMPAT 725 struct uinput_ff_upload_compat { 726 __u32 request_id; 727 __s32 retval; 728 struct ff_effect_compat effect; 729 struct ff_effect_compat old; 730 }; 731 732 static int uinput_ff_upload_to_user(char __user *buffer, 733 const struct uinput_ff_upload *ff_up) 734 { 735 if (in_compat_syscall()) { 736 struct uinput_ff_upload_compat ff_up_compat; 737 738 ff_up_compat.request_id = ff_up->request_id; 739 ff_up_compat.retval = ff_up->retval; 740 /* 741 * It so happens that the pointer that gives us the trouble 742 * is the last field in the structure. Since we don't support 743 * custom waveforms in uinput anyway we can just copy the whole 744 * thing (to the compat size) and ignore the pointer. 745 */ 746 memcpy(&ff_up_compat.effect, &ff_up->effect, 747 sizeof(struct ff_effect_compat)); 748 memcpy(&ff_up_compat.old, &ff_up->old, 749 sizeof(struct ff_effect_compat)); 750 751 if (copy_to_user(buffer, &ff_up_compat, 752 sizeof(struct uinput_ff_upload_compat))) 753 return -EFAULT; 754 } else { 755 if (copy_to_user(buffer, ff_up, 756 sizeof(struct uinput_ff_upload))) 757 return -EFAULT; 758 } 759 760 return 0; 761 } 762 763 static int uinput_ff_upload_from_user(const char __user *buffer, 764 struct uinput_ff_upload *ff_up) 765 { 766 if (in_compat_syscall()) { 767 struct uinput_ff_upload_compat ff_up_compat; 768 769 if (copy_from_user(&ff_up_compat, buffer, 770 sizeof(struct uinput_ff_upload_compat))) 771 return -EFAULT; 772 773 ff_up->request_id = ff_up_compat.request_id; 774 ff_up->retval = ff_up_compat.retval; 775 memcpy(&ff_up->effect, &ff_up_compat.effect, 776 sizeof(struct ff_effect_compat)); 777 memcpy(&ff_up->old, &ff_up_compat.old, 778 sizeof(struct ff_effect_compat)); 779 780 } else { 781 if (copy_from_user(ff_up, buffer, 782 sizeof(struct uinput_ff_upload))) 783 return -EFAULT; 784 } 785 786 return 0; 787 } 788 789 #else 790 791 static int uinput_ff_upload_to_user(char __user *buffer, 792 const struct uinput_ff_upload *ff_up) 793 { 794 if (copy_to_user(buffer, ff_up, sizeof(struct uinput_ff_upload))) 795 return -EFAULT; 796 797 return 0; 798 } 799 800 static int uinput_ff_upload_from_user(const char __user *buffer, 801 struct uinput_ff_upload *ff_up) 802 { 803 if (copy_from_user(ff_up, buffer, sizeof(struct uinput_ff_upload))) 804 return -EFAULT; 805 806 return 0; 807 } 808 809 #endif 810 811 #define uinput_set_bit(_arg, _bit, _max) \ 812 ({ \ 813 int __ret = 0; \ 814 if (udev->state == UIST_CREATED) \ 815 __ret = -EINVAL; \ 816 else if ((_arg) > (_max)) \ 817 __ret = -EINVAL; \ 818 else set_bit((_arg), udev->dev->_bit); \ 819 __ret; \ 820 }) 821 822 static int uinput_str_to_user(void __user *dest, const char *str, 823 unsigned int maxlen) 824 { 825 char __user *p = dest; 826 int len, ret; 827 828 if (!str) 829 return -ENOENT; 830 831 if (maxlen == 0) 832 return -EINVAL; 833 834 len = strlen(str) + 1; 835 if (len > maxlen) 836 len = maxlen; 837 838 ret = copy_to_user(p, str, len); 839 if (ret) 840 return -EFAULT; 841 842 /* force terminating '\0' */ 843 ret = put_user(0, p + len - 1); 844 return ret ? -EFAULT : len; 845 } 846 847 static long uinput_ioctl_handler(struct file *file, unsigned int cmd, 848 unsigned long arg, void __user *p) 849 { 850 int retval; 851 struct uinput_device *udev = file->private_data; 852 struct uinput_ff_upload ff_up; 853 struct uinput_ff_erase ff_erase; 854 struct uinput_request *req; 855 char *phys; 856 const char *name; 857 unsigned int size; 858 859 retval = mutex_lock_interruptible(&udev->mutex); 860 if (retval) 861 return retval; 862 863 if (!udev->dev) { 864 udev->dev = input_allocate_device(); 865 if (!udev->dev) { 866 retval = -ENOMEM; 867 goto out; 868 } 869 } 870 871 switch (cmd) { 872 case UI_GET_VERSION: 873 if (put_user(UINPUT_VERSION, (unsigned int __user *)p)) 874 retval = -EFAULT; 875 goto out; 876 877 case UI_DEV_CREATE: 878 retval = uinput_create_device(udev); 879 goto out; 880 881 case UI_DEV_DESTROY: 882 uinput_destroy_device(udev); 883 goto out; 884 885 case UI_DEV_SETUP: 886 retval = uinput_dev_setup(udev, p); 887 goto out; 888 889 /* UI_ABS_SETUP is handled in the variable size ioctls */ 890 891 case UI_SET_EVBIT: 892 retval = uinput_set_bit(arg, evbit, EV_MAX); 893 goto out; 894 895 case UI_SET_KEYBIT: 896 retval = uinput_set_bit(arg, keybit, KEY_MAX); 897 goto out; 898 899 case UI_SET_RELBIT: 900 retval = uinput_set_bit(arg, relbit, REL_MAX); 901 goto out; 902 903 case UI_SET_ABSBIT: 904 retval = uinput_set_bit(arg, absbit, ABS_MAX); 905 goto out; 906 907 case UI_SET_MSCBIT: 908 retval = uinput_set_bit(arg, mscbit, MSC_MAX); 909 goto out; 910 911 case UI_SET_LEDBIT: 912 retval = uinput_set_bit(arg, ledbit, LED_MAX); 913 goto out; 914 915 case UI_SET_SNDBIT: 916 retval = uinput_set_bit(arg, sndbit, SND_MAX); 917 goto out; 918 919 case UI_SET_FFBIT: 920 retval = uinput_set_bit(arg, ffbit, FF_MAX); 921 goto out; 922 923 case UI_SET_SWBIT: 924 retval = uinput_set_bit(arg, swbit, SW_MAX); 925 goto out; 926 927 case UI_SET_PROPBIT: 928 retval = uinput_set_bit(arg, propbit, INPUT_PROP_MAX); 929 goto out; 930 931 case UI_SET_PHYS: 932 if (udev->state == UIST_CREATED) { 933 retval = -EINVAL; 934 goto out; 935 } 936 937 phys = strndup_user(p, 1024); 938 if (IS_ERR(phys)) { 939 retval = PTR_ERR(phys); 940 goto out; 941 } 942 943 kfree(udev->dev->phys); 944 udev->dev->phys = phys; 945 goto out; 946 947 case UI_BEGIN_FF_UPLOAD: 948 retval = uinput_ff_upload_from_user(p, &ff_up); 949 if (retval) 950 goto out; 951 952 req = uinput_request_find(udev, ff_up.request_id); 953 if (!req || req->code != UI_FF_UPLOAD || 954 !req->u.upload.effect) { 955 retval = -EINVAL; 956 goto out; 957 } 958 959 ff_up.retval = 0; 960 ff_up.effect = *req->u.upload.effect; 961 if (req->u.upload.old) 962 ff_up.old = *req->u.upload.old; 963 else 964 memset(&ff_up.old, 0, sizeof(struct ff_effect)); 965 966 retval = uinput_ff_upload_to_user(p, &ff_up); 967 goto out; 968 969 case UI_BEGIN_FF_ERASE: 970 if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) { 971 retval = -EFAULT; 972 goto out; 973 } 974 975 req = uinput_request_find(udev, ff_erase.request_id); 976 if (!req || req->code != UI_FF_ERASE) { 977 retval = -EINVAL; 978 goto out; 979 } 980 981 ff_erase.retval = 0; 982 ff_erase.effect_id = req->u.effect_id; 983 if (copy_to_user(p, &ff_erase, sizeof(ff_erase))) { 984 retval = -EFAULT; 985 goto out; 986 } 987 988 goto out; 989 990 case UI_END_FF_UPLOAD: 991 retval = uinput_ff_upload_from_user(p, &ff_up); 992 if (retval) 993 goto out; 994 995 req = uinput_request_find(udev, ff_up.request_id); 996 if (!req || req->code != UI_FF_UPLOAD || 997 !req->u.upload.effect) { 998 retval = -EINVAL; 999 goto out; 1000 } 1001 1002 req->retval = ff_up.retval; 1003 complete(&req->done); 1004 goto out; 1005 1006 case UI_END_FF_ERASE: 1007 if (copy_from_user(&ff_erase, p, sizeof(ff_erase))) { 1008 retval = -EFAULT; 1009 goto out; 1010 } 1011 1012 req = uinput_request_find(udev, ff_erase.request_id); 1013 if (!req || req->code != UI_FF_ERASE) { 1014 retval = -EINVAL; 1015 goto out; 1016 } 1017 1018 req->retval = ff_erase.retval; 1019 complete(&req->done); 1020 goto out; 1021 } 1022 1023 size = _IOC_SIZE(cmd); 1024 1025 /* Now check variable-length commands */ 1026 switch (cmd & ~IOCSIZE_MASK) { 1027 case UI_GET_SYSNAME(0): 1028 if (udev->state != UIST_CREATED) { 1029 retval = -ENOENT; 1030 goto out; 1031 } 1032 name = dev_name(&udev->dev->dev); 1033 retval = uinput_str_to_user(p, name, size); 1034 goto out; 1035 1036 case UI_ABS_SETUP & ~IOCSIZE_MASK: 1037 retval = uinput_abs_setup(udev, p, size); 1038 goto out; 1039 } 1040 1041 retval = -EINVAL; 1042 out: 1043 mutex_unlock(&udev->mutex); 1044 return retval; 1045 } 1046 1047 static long uinput_ioctl(struct file *file, unsigned int cmd, unsigned long arg) 1048 { 1049 return uinput_ioctl_handler(file, cmd, arg, (void __user *)arg); 1050 } 1051 1052 #ifdef CONFIG_COMPAT 1053 1054 #define UI_SET_PHYS_COMPAT _IOW(UINPUT_IOCTL_BASE, 108, compat_uptr_t) 1055 1056 static long uinput_compat_ioctl(struct file *file, 1057 unsigned int cmd, unsigned long arg) 1058 { 1059 if (cmd == UI_SET_PHYS_COMPAT) 1060 cmd = UI_SET_PHYS; 1061 1062 return uinput_ioctl_handler(file, cmd, arg, compat_ptr(arg)); 1063 } 1064 #endif 1065 1066 static const struct file_operations uinput_fops = { 1067 .owner = THIS_MODULE, 1068 .open = uinput_open, 1069 .release = uinput_release, 1070 .read = uinput_read, 1071 .write = uinput_write, 1072 .poll = uinput_poll, 1073 .unlocked_ioctl = uinput_ioctl, 1074 #ifdef CONFIG_COMPAT 1075 .compat_ioctl = uinput_compat_ioctl, 1076 #endif 1077 .llseek = no_llseek, 1078 }; 1079 1080 static struct miscdevice uinput_misc = { 1081 .fops = &uinput_fops, 1082 .minor = UINPUT_MINOR, 1083 .name = UINPUT_NAME, 1084 }; 1085 module_misc_device(uinput_misc); 1086 1087 MODULE_ALIAS_MISCDEV(UINPUT_MINOR); 1088 MODULE_ALIAS("devname:" UINPUT_NAME); 1089 1090 MODULE_AUTHOR("Aristeu Sergio Rozanski Filho"); 1091 MODULE_DESCRIPTION("User level driver support for input subsystem"); 1092 MODULE_LICENSE("GPL"); 1093