drivers/hid/usbhid/hiddev.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  *  Copyright (c) 2001 Paul Stewart
   4  *  Copyright (c) 2001 Vojtech Pavlik
   5  *
   6  *  HID char devices, giving access to raw HID device events.
   7  */
   8
   9 /*
  10  *
  11  * Should you need to contact me, the author, you can do so either by
  12  * e-mail - mail your message to Paul Stewart <stewart@wetlogic.net>
  13  */
  14
  15 #include <linux/poll.h>
  16 #include <linux/slab.h>
  17 #include <linux/sched/signal.h>
  18 #include <linux/module.h>
  19 #include <linux/init.h>
  20 #include <linux/input.h>
  21 #include <linux/usb.h>
  22 #include <linux/hid.h>
  23 #include <linux/hiddev.h>
  24 #include <linux/compat.h>
  25 #include <linux/vmalloc.h>
  26 #include <linux/nospec.h>
  27 #include "usbhid.h"
  28
  29 #ifdef CONFIG_USB_DYNAMIC_MINORS
  30 #define HIDDEV_MINOR_BASE       0
  31 #define HIDDEV_MINORS           256
  32 #else
  33 #define HIDDEV_MINOR_BASE       96
  34 #define HIDDEV_MINORS           16
  35 #endif
  36 #define HIDDEV_BUFFER_SIZE      2048
  37
  38 struct hiddev_list {
  39         struct hiddev_usage_ref buffer[HIDDEV_BUFFER_SIZE];
  40         int head;
  41         int tail;
  42         unsigned flags;
  43         struct fasync_struct *fasync;
  44         struct hiddev *hiddev;
  45         struct list_head node;
  46         struct mutex thread_lock;
  47 };
  48
  49 /*
  50  * Find a report, given the report's type and ID.  The ID can be specified
  51  * indirectly by REPORT_ID_FIRST (which returns the first report of the given
  52  * type) or by (REPORT_ID_NEXT | old_id), which returns the next report of the
  53  * given type which follows old_id.
  54  */
  55 static struct hid_report *
  56 hiddev_lookup_report(struct hid_device *hid, struct hiddev_report_info *rinfo)
  57 {
  58         unsigned int flags = rinfo->report_id & ~HID_REPORT_ID_MASK;
  59         unsigned int rid = rinfo->report_id & HID_REPORT_ID_MASK;
  60         struct hid_report_enum *report_enum;
  61         struct hid_report *report;
  62         struct list_head *list;
  63
  64         if (rinfo->report_type < HID_REPORT_TYPE_MIN ||
  65             rinfo->report_type > HID_REPORT_TYPE_MAX)
  66                 return NULL;
  67
  68         report_enum = hid->report_enum +
  69                 (rinfo->report_type - HID_REPORT_TYPE_MIN);
  70
  71         switch (flags) {
  72         case 0: /* Nothing to do -- report_id is already set correctly */
  73                 break;
  74
  75         case HID_REPORT_ID_FIRST:
  76                 if (list_empty(&report_enum->report_list))
  77                         return NULL;
  78
  79                 list = report_enum->report_list.next;
  80                 report = list_entry(list, struct hid_report, list);
  81                 rinfo->report_id = report->id;
  82                 break;
  83
  84         case HID_REPORT_ID_NEXT:
  85                 report = report_enum->report_id_hash[rid];
  86                 if (!report)
  87                         return NULL;
  88
  89                 list = report->list.next;
  90                 if (list == &report_enum->report_list)
  91                         return NULL;
  92
  93                 report = list_entry(list, struct hid_report, list);
  94                 rinfo->report_id = report->id;
  95                 break;
  96
  97         default:
  98                 return NULL;
  99         }
 100
 101         return report_enum->report_id_hash[rinfo->report_id];
 102 }
 103
 104 /*
 105  * Perform an exhaustive search of the report table for a usage, given its
 106  * type and usage id.
 107  */
 108 static struct hid_field *
 109 hiddev_lookup_usage(struct hid_device *hid, struct hiddev_usage_ref *uref)
 110 {
 111         int i, j;
 112         struct hid_report *report;
 113         struct hid_report_enum *report_enum;
 114         struct hid_field *field;
 115
 116         if (uref->report_type < HID_REPORT_TYPE_MIN ||
 117             uref->report_type > HID_REPORT_TYPE_MAX)
 118                 return NULL;
 119
 120         report_enum = hid->report_enum +
 121                 (uref->report_type - HID_REPORT_TYPE_MIN);
 122
 123         list_for_each_entry(report, &report_enum->report_list, list) {
 124                 for (i = 0; i < report->maxfield; i++) {
 125                         field = report->field[i];
 126                         for (j = 0; j < field->maxusage; j++) {
 127                                 if (field->usage[j].hid == uref->usage_code) {
 128                                         uref->report_id = report->id;
 129                                         uref->field_index = i;
 130                                         uref->usage_index = j;
 131                                         return field;
 132                                 }
 133                         }
 134                 }
 135         }
 136
 137         return NULL;
 138 }
 139
 140 static void hiddev_send_event(struct hid_device *hid,
 141                               struct hiddev_usage_ref *uref)
 142 {
 143         struct hiddev *hiddev = hid->hiddev;
 144         struct hiddev_list *list;
 145         unsigned long flags;
 146
 147         spin_lock_irqsave(&hiddev->list_lock, flags);
 148         list_for_each_entry(list, &hiddev->list, node) {
 149                 if (uref->field_index != HID_FIELD_INDEX_NONE ||
 150                     (list->flags & HIDDEV_FLAG_REPORT) != 0) {
 151                         list->buffer[list->head] = *uref;
 152                         list->head = (list->head + 1) &
 153                                 (HIDDEV_BUFFER_SIZE - 1);
 154                         kill_fasync(&list->fasync, SIGIO, POLL_IN);
 155                 }
 156         }
 157         spin_unlock_irqrestore(&hiddev->list_lock, flags);
 158
 159         wake_up_interruptible(&hiddev->wait);
 160 }
 161
 162 /*
 163  * This is where hid.c calls into hiddev to pass an event that occurred over
 164  * the interrupt pipe
 165  */
 166 void hiddev_hid_event(struct hid_device *hid, struct hid_field *field,
 167                       struct hid_usage *usage, __s32 value)
 168 {
 169         unsigned type = field->report_type;
 170         struct hiddev_usage_ref uref;
 171
 172         uref.report_type =
 173           (type == HID_INPUT_REPORT) ? HID_REPORT_TYPE_INPUT :
 174           ((type == HID_OUTPUT_REPORT) ? HID_REPORT_TYPE_OUTPUT :
 175            ((type == HID_FEATURE_REPORT) ? HID_REPORT_TYPE_FEATURE : 0));
 176         uref.report_id = field->report->id;
 177         uref.field_index = field->index;
 178         uref.usage_index = (usage - field->usage);
 179         uref.usage_code = usage->hid;
 180         uref.value = value;
 181
 182         hiddev_send_event(hid, &uref);
 183 }
 184 EXPORT_SYMBOL_GPL(hiddev_hid_event);
 185
 186 void hiddev_report_event(struct hid_device *hid, struct hid_report *report)
 187 {
 188         unsigned type = report->type;
 189         struct hiddev_usage_ref uref;
 190
 191         memset(&uref, 0, sizeof(uref));
 192         uref.report_type =
 193           (type == HID_INPUT_REPORT) ? HID_REPORT_TYPE_INPUT :
 194           ((type == HID_OUTPUT_REPORT) ? HID_REPORT_TYPE_OUTPUT :
 195            ((type == HID_FEATURE_REPORT) ? HID_REPORT_TYPE_FEATURE : 0));
 196         uref.report_id = report->id;
 197         uref.field_index = HID_FIELD_INDEX_NONE;
 198
 199         hiddev_send_event(hid, &uref);
 200 }
 201
 202 /*
 203  * fasync file op
 204  */
 205 static int hiddev_fasync(int fd, struct file *file, int on)
 206 {
 207         struct hiddev_list *list = file->private_data;
 208
 209         return fasync_helper(fd, file, on, &list->fasync);
 210 }
 211
 212
 213 /*
 214  * release file op
 215  */
 216 static int hiddev_release(struct inode * inode, struct file * file)
 217 {
 218         struct hiddev_list *list = file->private_data;
 219         unsigned long flags;
 220
 221         spin_lock_irqsave(&list->hiddev->list_lock, flags);
 222         list_del(&list->node);
 223         spin_unlock_irqrestore(&list->hiddev->list_lock, flags);
 224
 225         mutex_lock(&list->hiddev->existancelock);
 226         if (!--list->hiddev->open) {
 227                 if (list->hiddev->exist) {
 228                         hid_hw_close(list->hiddev->hid);
 229                         hid_hw_power(list->hiddev->hid, PM_HINT_NORMAL);
 230                 } else {
 231                         mutex_unlock(&list->hiddev->existancelock);
 232                         kfree(list->hiddev);
 233                         vfree(list);
 234                         return 0;
 235                 }
 236         }
 237
 238         mutex_unlock(&list->hiddev->existancelock);
 239         vfree(list);
 240
 241         return 0;
 242 }
 243
 244 /*
 245  * open file op
 246  */
 247 static int hiddev_open(struct inode *inode, struct file *file)
 248 {
 249         struct hiddev_list *list;
 250         struct usb_interface *intf;
 251         struct hid_device *hid;
 252         struct hiddev *hiddev;
 253         int res;
 254
 255         intf = usbhid_find_interface(iminor(inode));
 256         if (!intf)
 257                 return -ENODEV;
 258         hid = usb_get_intfdata(intf);
 259         hiddev = hid->hiddev;
 260
 261         if (!(list = vzalloc(sizeof(struct hiddev_list))))
 262                 return -ENOMEM;
 263         mutex_init(&list->thread_lock);
 264         list->hiddev = hiddev;
 265         file->private_data = list;
 266
 267         /*
 268          * no need for locking because the USB major number
 269          * is shared which usbcore guards against disconnect
 270          */
 271         if (list->hiddev->exist) {
 272                 if (!list->hiddev->open++) {
 273                         res = hid_hw_open(hiddev->hid);
 274                         if (res < 0)
 275                                 goto bail;
 276                 }
 277         } else {
 278                 res = -ENODEV;
 279                 goto bail;
 280         }
 281
 282         spin_lock_irq(&list->hiddev->list_lock);
 283         list_add_tail(&list->node, &hiddev->list);
 284         spin_unlock_irq(&list->hiddev->list_lock);
 285
 286         mutex_lock(&hiddev->existancelock);
 287         /*
 288          * recheck exist with existance lock held to
 289          * avoid opening a disconnected device
 290          */
 291         if (!list->hiddev->exist) {
 292                 res = -ENODEV;
 293                 goto bail_unlock;
 294         }
 295         if (!list->hiddev->open++)
 296                 if (list->hiddev->exist) {
 297                         struct hid_device *hid = hiddev->hid;
 298                         res = hid_hw_power(hid, PM_HINT_FULLON);
 299                         if (res < 0)
 300                                 goto bail_unlock;
 301                         res = hid_hw_open(hid);
 302                         if (res < 0)
 303                                 goto bail_normal_power;
 304                 }
 305         mutex_unlock(&hiddev->existancelock);
 306         return 0;
 307 bail_normal_power:
 308         hid_hw_power(hid, PM_HINT_NORMAL);
 309 bail_unlock:
 310         mutex_unlock(&hiddev->existancelock);
 311
 312         spin_lock_irq(&list->hiddev->list_lock);
 313         list_del(&list->node);
 314         spin_unlock_irq(&list->hiddev->list_lock);
 315 bail:
 316         file->private_data = NULL;
 317         vfree(list);
 318         return res;
 319 }
 320
 321 /*
 322  * "write" file op
 323  */
 324 static ssize_t hiddev_write(struct file * file, const char __user * buffer, size_t count, loff_t *ppos)
 325 {
 326         return -EINVAL;
 327 }
 328
 329 /*
 330  * "read" file op
 331  */
 332 static ssize_t hiddev_read(struct file * file, char __user * buffer, size_t count, loff_t *ppos)
 333 {
 334         DEFINE_WAIT(wait);
 335         struct hiddev_list *list = file->private_data;
 336         int event_size;
 337         int retval;
 338
 339         event_size = ((list->flags & HIDDEV_FLAG_UREF) != 0) ?
 340                 sizeof(struct hiddev_usage_ref) : sizeof(struct hiddev_event);
 341
 342         if (count < event_size)
 343                 return 0;
 344
 345         /* lock against other threads */
 346         retval = mutex_lock_interruptible(&list->thread_lock);
 347         if (retval)
 348                 return -ERESTARTSYS;
 349
 350         while (retval == 0) {
 351                 if (list->head == list->tail) {
 352                         prepare_to_wait(&list->hiddev->wait, &wait, TASK_INTERRUPTIBLE);
 353
 354                         while (list->head == list->tail) {
 355                                 if (signal_pending(current)) {
 356                                         retval = -ERESTARTSYS;
 357                                         break;
 358                                 }
 359                                 if (!list->hiddev->exist) {
 360                                         retval = -EIO;
 361                                         break;
 362                                 }
 363                                 if (file->f_flags & O_NONBLOCK) {
 364                                         retval = -EAGAIN;
 365                                         break;
 366                                 }
 367
 368                                 /* let O_NONBLOCK tasks run */
 369                                 mutex_unlock(&list->thread_lock);
 370                                 schedule();
 371                                 if (mutex_lock_interruptible(&list->thread_lock)) {
 372                                         finish_wait(&list->hiddev->wait, &wait);
 373                                         return -EINTR;
 374                                 }
 375                                 set_current_state(TASK_INTERRUPTIBLE);
 376                         }
 377                         finish_wait(&list->hiddev->wait, &wait);
 378
 379                 }
 380
 381                 if (retval) {
 382                         mutex_unlock(&list->thread_lock);
 383                         return retval;
 384                 }
 385
 386
 387                 while (list->head != list->tail &&
 388                        retval + event_size <= count) {
 389                         if ((list->flags & HIDDEV_FLAG_UREF) == 0) {
 390                                 if (list->buffer[list->tail].field_index != HID_FIELD_INDEX_NONE) {
 391                                         struct hiddev_event event;
 392
 393                                         event.hid = list->buffer[list->tail].usage_code;
 394                                         event.value = list->buffer[list->tail].value;
 395                                         if (copy_to_user(buffer + retval, &event, sizeof(struct hiddev_event))) {
 396                                                 mutex_unlock(&list->thread_lock);
 397                                                 return -EFAULT;
 398                                         }
 399                                         retval += sizeof(struct hiddev_event);
 400                                 }
 401                         } else {
 402                                 if (list->buffer[list->tail].field_index != HID_FIELD_INDEX_NONE ||
 403                                     (list->flags & HIDDEV_FLAG_REPORT) != 0) {
 404
 405                                         if (copy_to_user(buffer + retval, list->buffer + list->tail, sizeof(struct hiddev_usage_ref))) {
 406                                                 mutex_unlock(&list->thread_lock);
 407                                                 return -EFAULT;
 408                                         }
 409                                         retval += sizeof(struct hiddev_usage_ref);
 410                                 }
 411                         }
 412                         list->tail = (list->tail + 1) & (HIDDEV_BUFFER_SIZE - 1);
 413                 }
 414
 415         }
 416         mutex_unlock(&list->thread_lock);
 417
 418         return retval;
 419 }
 420
 421 /*
 422  * "poll" file op
 423  * No kernel lock - fine
 424  */
 425 static __poll_t hiddev_poll(struct file *file, poll_table *wait)
 426 {
 427         struct hiddev_list *list = file->private_data;
 428
 429         poll_wait(file, &list->hiddev->wait, wait);
 430         if (list->head != list->tail)
 431                 return EPOLLIN | EPOLLRDNORM;
 432         if (!list->hiddev->exist)
 433                 return EPOLLERR | EPOLLHUP;
 434         return 0;
 435 }
 436
 437 /*
 438  * "ioctl" file op
 439  */
 440 static noinline int hiddev_ioctl_usage(struct hiddev *hiddev, unsigned int cmd, void __user *user_arg)
 441 {
 442         struct hid_device *hid = hiddev->hid;
 443         struct hiddev_report_info rinfo;
 444         struct hiddev_usage_ref_multi *uref_multi = NULL;
 445         struct hiddev_usage_ref *uref;
 446         struct hid_report *report;
 447         struct hid_field *field;
 448         int i;
 449
 450         uref_multi = kmalloc(sizeof(struct hiddev_usage_ref_multi), GFP_KERNEL);
 451         if (!uref_multi)
 452                 return -ENOMEM;
 453         uref = &uref_multi->uref;
 454         if (cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) {
 455                 if (copy_from_user(uref_multi, user_arg,
 456                                    sizeof(*uref_multi)))
 457                         goto fault;
 458         } else {
 459                 if (copy_from_user(uref, user_arg, sizeof(*uref)))
 460                         goto fault;
 461         }
 462
 463         switch (cmd) {
 464         case HIDIOCGUCODE:
 465                 rinfo.report_type = uref->report_type;
 466                 rinfo.report_id = uref->report_id;
 467                 if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
 468                         goto inval;
 469
 470                 if (uref->field_index >= report->maxfield)
 471                         goto inval;
 472                 uref->field_index = array_index_nospec(uref->field_index,
 473                                                        report->maxfield);
 474
 475                 field = report->field[uref->field_index];
 476                 if (uref->usage_index >= field->maxusage)
 477                         goto inval;
 478                 uref->usage_index = array_index_nospec(uref->usage_index,
 479                                                        field->maxusage);
 480
 481                 uref->usage_code = field->usage[uref->usage_index].hid;
 482
 483                 if (copy_to_user(user_arg, uref, sizeof(*uref)))
 484                         goto fault;
 485
 486                 goto goodreturn;
 487
 488         default:
 489                 if (cmd != HIDIOCGUSAGE &&
 490                     cmd != HIDIOCGUSAGES &&
 491                     uref->report_type == HID_REPORT_TYPE_INPUT)
 492                         goto inval;
 493
 494                 if (uref->report_id == HID_REPORT_ID_UNKNOWN) {
 495                         field = hiddev_lookup_usage(hid, uref);
 496                         if (field == NULL)
 497                                 goto inval;
 498                 } else {
 499                         rinfo.report_type = uref->report_type;
 500                         rinfo.report_id = uref->report_id;
 501                         if ((report = hiddev_lookup_report(hid, &rinfo)) == NULL)
 502                                 goto inval;
 503
 504                         if (uref->field_index >= report->maxfield)
 505                                 goto inval;
 506                         uref->field_index = array_index_nospec(uref->field_index,
 507                                                                report->maxfield);
 508
 509                         field = report->field[uref->field_index];
 510
 511                         if (cmd == HIDIOCGCOLLECTIONINDEX) {
 512                                 if (uref->usage_index >= field->maxusage)
 513                                         goto inval;
 514                                 uref->usage_index =
 515                                         array_index_nospec(uref->usage_index,
 516                                                            field->maxusage);
 517                         } else if (uref->usage_index >= field->report_count)
 518                                 goto inval;
 519                 }
 520
 521                 if (cmd == HIDIOCGUSAGES || cmd == HIDIOCSUSAGES) {
 522                         if (uref_multi->num_values > HID_MAX_MULTI_USAGES ||
 523                             uref->usage_index + uref_multi->num_values >
 524                             field->report_count)
 525                                 goto inval;
 526
 527                         uref->usage_index =
 528                                 array_index_nospec(uref->usage_index,
 529                                                    field->report_count -
 530                                                    uref_multi->num_values);
 531                 }
 532
 533                 switch (cmd) {
 534                 case HIDIOCGUSAGE:
 535                         uref->value = field->value[uref->usage_index];
 536                         if (copy_to_user(user_arg, uref, sizeof(*uref)))
 537                                 goto fault;
 538                         goto goodreturn;
 539
 540                 case HIDIOCSUSAGE:
 541                         field->value[uref->usage_index] = uref->value;
 542                         goto goodreturn;
 543
 544                 case HIDIOCGCOLLECTIONINDEX:
 545                         i = field->usage[uref->usage_index].collection_index;
 546                         kfree(uref_multi);
 547                         return i;
 548                 case HIDIOCGUSAGES:
 549                         for (i = 0; i < uref_multi->num_values; i++)
 550                                 uref_multi->values[i] =
 551                                     field->value[uref->usage_index + i];
 552                         if (copy_to_user(user_arg, uref_multi,
 553                                          sizeof(*uref_multi)))
 554                                 goto fault;
 555                         goto goodreturn;
 556                 case HIDIOCSUSAGES:
 557                         for (i = 0; i < uref_multi->num_values; i++)
 558                                 field->value[uref->usage_index + i] =
 559                                     uref_multi->values[i];
 560                         goto goodreturn;
 561                 }
 562
 563 goodreturn:
 564                 kfree(uref_multi);
 565                 return 0;
 566 fault:
 567                 kfree(uref_multi);
 568                 return -EFAULT;
 569 inval:
 570                 kfree(uref_multi);
 571                 return -EINVAL;
 572         }
 573 }
 574
 575 static noinline int hiddev_ioctl_string(struct hiddev *hiddev, unsigned int cmd, void __user *user_arg)
 576 {
 577         struct hid_device *hid = hiddev->hid;
 578         struct usb_device *dev = hid_to_usb_dev(hid);
 579         int idx, len;
 580         char *buf;
 581
 582         if (get_user(idx, (int __user *)user_arg))
 583                 return -EFAULT;
 584
 585         if ((buf = kmalloc(HID_STRING_SIZE, GFP_KERNEL)) == NULL)
 586                 return -ENOMEM;
 587
 588         if ((len = usb_string(dev, idx, buf, HID_STRING_SIZE-1)) < 0) {
 589                 kfree(buf);
 590                 return -EINVAL;
 591         }
 592
 593         if (copy_to_user(user_arg+sizeof(int), buf, len+1)) {
 594                 kfree(buf);
 595                 return -EFAULT;
 596         }
 597
 598         kfree(buf);
 599
 600         return len;
 601 }
 602
 603 static long hiddev_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 604 {
 605         struct hiddev_list *list = file->private_data;
 606         struct hiddev *hiddev = list->hiddev;
 607         struct hid_device *hid;
 608         struct hiddev_collection_info cinfo;
 609         struct hiddev_report_info rinfo;
 610         struct hiddev_field_info finfo;
 611         struct hiddev_devinfo dinfo;
 612         struct hid_report *report;
 613         struct hid_field *field;
 614         void __user *user_arg = (void __user *)arg;
 615         int i, r = -EINVAL;
 616
 617         /* Called without BKL by compat methods so no BKL taken */
 618
 619         mutex_lock(&hiddev->existancelock);
 620         if (!hiddev->exist) {
 621                 r = -ENODEV;
 622                 goto ret_unlock;
 623         }
 624
 625         hid = hiddev->hid;
 626
 627         switch (cmd) {
 628
 629         case HIDIOCGVERSION:
 630                 r = put_user(HID_VERSION, (int __user *)arg) ?
 631                         -EFAULT : 0;
 632                 break;
 633
 634         case HIDIOCAPPLICATION:
 635                 if (arg >= hid->maxapplication)
 636                         break;
 637
 638                 for (i = 0; i < hid->maxcollection; i++)
 639                         if (hid->collection[i].type ==
 640                             HID_COLLECTION_APPLICATION && arg-- == 0)
 641                                 break;
 642
 643                 if (i < hid->maxcollection)
 644                         r = hid->collection[i].usage;
 645                 break;
 646
 647         case HIDIOCGDEVINFO:
 648                 {
 649                         struct usb_device *dev = hid_to_usb_dev(hid);
 650                         struct usbhid_device *usbhid = hid->driver_data;
 651
 652                         memset(&dinfo, 0, sizeof(dinfo));
 653
 654                         dinfo.bustype = BUS_USB;
 655                         dinfo.busnum = dev->bus->busnum;
 656                         dinfo.devnum = dev->devnum;
 657                         dinfo.ifnum = usbhid->ifnum;
 658                         dinfo.vendor = le16_to_cpu(dev->descriptor.idVendor);
 659                         dinfo.product = le16_to_cpu(dev->descriptor.idProduct);
 660                         dinfo.version = le16_to_cpu(dev->descriptor.bcdDevice);
 661                         dinfo.num_applications = hid->maxapplication;
 662
 663                         r = copy_to_user(user_arg, &dinfo, sizeof(dinfo)) ?
 664                                 -EFAULT : 0;
 665                         break;
 666                 }
 667
 668         case HIDIOCGFLAG:
 669                 r = put_user(list->flags, (int __user *)arg) ?
 670                         -EFAULT : 0;
 671                 break;
 672
 673         case HIDIOCSFLAG:
 674                 {
 675                         int newflags;
 676
 677                         if (get_user(newflags, (int __user *)arg)) {
 678                                 r = -EFAULT;
 679                                 break;
 680                         }
 681
 682                         if ((newflags & ~HIDDEV_FLAGS) != 0 ||
 683                             ((newflags & HIDDEV_FLAG_REPORT) != 0 &&
 684                              (newflags & HIDDEV_FLAG_UREF) == 0))
 685                                 break;
 686
 687                         list->flags = newflags;
 688
 689                         r = 0;
 690                         break;
 691                 }
 692
 693         case HIDIOCGSTRING:
 694                 r = hiddev_ioctl_string(hiddev, cmd, user_arg);
 695                 break;
 696
 697         case HIDIOCINITREPORT:
 698                 usbhid_init_reports(hid);
 699                 hiddev->initialized = true;
 700                 r = 0;
 701                 break;
 702
 703         case HIDIOCGREPORT:
 704                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo))) {
 705                         r = -EFAULT;
 706                         break;
 707                 }
 708
 709                 if (rinfo.report_type == HID_REPORT_TYPE_OUTPUT)
 710                         break;
 711
 712                 report = hiddev_lookup_report(hid, &rinfo);
 713                 if (report == NULL)
 714                         break;
 715
 716                 hid_hw_request(hid, report, HID_REQ_GET_REPORT);
 717                 hid_hw_wait(hid);
 718
 719                 r = 0;
 720                 break;
 721
 722         case HIDIOCSREPORT:
 723                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo))) {
 724                         r = -EFAULT;
 725                         break;
 726                 }
 727
 728                 if (rinfo.report_type == HID_REPORT_TYPE_INPUT)
 729                         break;
 730
 731                 report = hiddev_lookup_report(hid, &rinfo);
 732                 if (report == NULL)
 733                         break;
 734
 735                 hid_hw_request(hid, report, HID_REQ_SET_REPORT);
 736                 hid_hw_wait(hid);
 737
 738                 r = 0;
 739                 break;
 740
 741         case HIDIOCGREPORTINFO:
 742                 if (copy_from_user(&rinfo, user_arg, sizeof(rinfo))) {
 743                         r = -EFAULT;
 744                         break;
 745                 }
 746
 747                 report = hiddev_lookup_report(hid, &rinfo);
 748                 if (report == NULL)
 749                         break;
 750
 751                 rinfo.num_fields = report->maxfield;
 752
 753                 r = copy_to_user(user_arg, &rinfo, sizeof(rinfo)) ?
 754                         -EFAULT : 0;
 755                 break;
 756
 757         case HIDIOCGFIELDINFO:
 758                 if (copy_from_user(&finfo, user_arg, sizeof(finfo))) {
 759                         r = -EFAULT;
 760                         break;
 761                 }
 762
 763                 rinfo.report_type = finfo.report_type;
 764                 rinfo.report_id = finfo.report_id;
 765
 766                 report = hiddev_lookup_report(hid, &rinfo);
 767                 if (report == NULL)
 768                         break;
 769
 770                 if (finfo.field_index >= report->maxfield)
 771                         break;
 772                 finfo.field_index = array_index_nospec(finfo.field_index,
 773                                                        report->maxfield);
 774
 775                 field = report->field[finfo.field_index];
 776                 memset(&finfo, 0, sizeof(finfo));
 777                 finfo.report_type = rinfo.report_type;
 778                 finfo.report_id = rinfo.report_id;
 779                 finfo.field_index = field->report_count - 1;
 780                 finfo.maxusage = field->maxusage;
 781                 finfo.flags = field->flags;
 782                 finfo.physical = field->physical;
 783                 finfo.logical = field->logical;
 784                 finfo.application = field->application;
 785                 finfo.logical_minimum = field->logical_minimum;
 786                 finfo.logical_maximum = field->logical_maximum;
 787                 finfo.physical_minimum = field->physical_minimum;
 788                 finfo.physical_maximum = field->physical_maximum;
 789                 finfo.unit_exponent = field->unit_exponent;
 790                 finfo.unit = field->unit;
 791
 792                 r = copy_to_user(user_arg, &finfo, sizeof(finfo)) ?
 793                         -EFAULT : 0;
 794                 break;
 795
 796         case HIDIOCGUCODE:
 797                 /* fall through */
 798         case HIDIOCGUSAGE:
 799         case HIDIOCSUSAGE:
 800         case HIDIOCGUSAGES:
 801         case HIDIOCSUSAGES:
 802         case HIDIOCGCOLLECTIONINDEX:
 803                 if (!hiddev->initialized) {
 804                         usbhid_init_reports(hid);
 805                         hiddev->initialized = true;
 806                 }
 807                 r = hiddev_ioctl_usage(hiddev, cmd, user_arg);
 808                 break;
 809
 810         case HIDIOCGCOLLECTIONINFO:
 811                 if (copy_from_user(&cinfo, user_arg, sizeof(cinfo))) {
 812                         r = -EFAULT;
 813                         break;
 814                 }
 815
 816                 if (cinfo.index >= hid->maxcollection)
 817                         break;
 818                 cinfo.index = array_index_nospec(cinfo.index,
 819                                                  hid->maxcollection);
 820
 821                 cinfo.type = hid->collection[cinfo.index].type;
 822                 cinfo.usage = hid->collection[cinfo.index].usage;
 823                 cinfo.level = hid->collection[cinfo.index].level;
 824
 825                 r = copy_to_user(user_arg, &cinfo, sizeof(cinfo)) ?
 826                         -EFAULT : 0;
 827                 break;
 828
 829         default:
 830                 if (_IOC_TYPE(cmd) != 'H' || _IOC_DIR(cmd) != _IOC_READ)
 831                         break;
 832
 833                 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGNAME(0))) {
 834                         int len = strlen(hid->name) + 1;
 835                         if (len > _IOC_SIZE(cmd))
 836                                  len = _IOC_SIZE(cmd);
 837                         r = copy_to_user(user_arg, hid->name, len) ?
 838                                 -EFAULT : len;
 839                         break;
 840                 }
 841
 842                 if (_IOC_NR(cmd) == _IOC_NR(HIDIOCGPHYS(0))) {
 843                         int len = strlen(hid->phys) + 1;
 844                         if (len > _IOC_SIZE(cmd))
 845                                 len = _IOC_SIZE(cmd);
 846                         r = copy_to_user(user_arg, hid->phys, len) ?
 847                                 -EFAULT : len;
 848                         break;
 849                 }
 850         }
 851
 852 ret_unlock:
 853         mutex_unlock(&hiddev->existancelock);
 854         return r;
 855 }
 856
 857 #ifdef CONFIG_COMPAT
 858 static long hiddev_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
 859 {
 860         return hiddev_ioctl(file, cmd, (unsigned long)compat_ptr(arg));
 861 }
 862 #endif
 863
 864 static const struct file_operations hiddev_fops = {
 865         .owner =        THIS_MODULE,
 866         .read =         hiddev_read,
 867         .write =        hiddev_write,
 868         .poll =         hiddev_poll,
 869         .open =         hiddev_open,
 870         .release =      hiddev_release,
 871         .unlocked_ioctl =       hiddev_ioctl,
 872         .fasync =       hiddev_fasync,
 873 #ifdef CONFIG_COMPAT
 874         .compat_ioctl   = hiddev_compat_ioctl,
 875 #endif
 876         .llseek         = noop_llseek,
 877 };
 878
 879 static char *hiddev_devnode(struct device *dev, umode_t *mode)
 880 {
 881         return kasprintf(GFP_KERNEL, "usb/%s", dev_name(dev));
 882 }
 883
 884 static struct usb_class_driver hiddev_class = {
 885         .name =         "hiddev%d",
 886         .devnode =      hiddev_devnode,
 887         .fops =         &hiddev_fops,
 888         .minor_base =   HIDDEV_MINOR_BASE,
 889 };
 890
 891 /*
 892  * This is where hid.c calls us to connect a hid device to the hiddev driver
 893  */
 894 int hiddev_connect(struct hid_device *hid, unsigned int force)
 895 {
 896         struct hiddev *hiddev;
 897         struct usbhid_device *usbhid = hid->driver_data;
 898         int retval;
 899
 900         if (!force) {
 901                 unsigned int i;
 902                 for (i = 0; i < hid->maxcollection; i++)
 903                         if (hid->collection[i].type ==
 904                             HID_COLLECTION_APPLICATION &&
 905                             !IS_INPUT_APPLICATION(hid->collection[i].usage))
 906                                 break;
 907
 908                 if (i == hid->maxcollection)
 909                         return -1;
 910         }
 911
 912         if (!(hiddev = kzalloc(sizeof(struct hiddev), GFP_KERNEL)))
 913                 return -1;
 914
 915         init_waitqueue_head(&hiddev->wait);
 916         INIT_LIST_HEAD(&hiddev->list);
 917         spin_lock_init(&hiddev->list_lock);
 918         mutex_init(&hiddev->existancelock);
 919         hid->hiddev = hiddev;
 920         hiddev->hid = hid;
 921         hiddev->exist = 1;
 922         retval = usb_register_dev(usbhid->intf, &hiddev_class);
 923         if (retval) {
 924                 hid_err(hid, "Not able to get a minor for this device\n");
 925                 hid->hiddev = NULL;
 926                 kfree(hiddev);
 927                 return -1;
 928         }
 929
 930         /*
 931          * If HID_QUIRK_NO_INIT_REPORTS is set, make sure we don't initialize
 932          * the reports.
 933          */
 934         hiddev->initialized = hid->quirks & HID_QUIRK_NO_INIT_REPORTS;
 935
 936         hiddev->minor = usbhid->intf->minor;
 937
 938         return 0;
 939 }
 940
 941 /*
 942  * This is where hid.c calls us to disconnect a hiddev device from the
 943  * corresponding hid device (usually because the usb device has disconnected)
 944  */
 945 static struct usb_class_driver hiddev_class;
 946 void hiddev_disconnect(struct hid_device *hid)
 947 {
 948         struct hiddev *hiddev = hid->hiddev;
 949         struct usbhid_device *usbhid = hid->driver_data;
 950
 951         usb_deregister_dev(usbhid->intf, &hiddev_class);
 952
 953         mutex_lock(&hiddev->existancelock);
 954         hiddev->exist = 0;
 955
 956         if (hiddev->open) {
 957                 mutex_unlock(&hiddev->existancelock);
 958                 hid_hw_close(hiddev->hid);
 959                 wake_up_interruptible(&hiddev->wait);
 960         } else {
 961                 mutex_unlock(&hiddev->existancelock);
 962                 kfree(hiddev);
 963         }
 964 }