1 /*
2 * Created: Fri Jan 8 09:01:26 1999 by faith@valinux.com
3 *
4 * Copyright 1999 Precision Insight, Inc., Cedar Park, Texas.
5 * Copyright 2000 VA Linux Systems, Inc., Sunnyvale, California.
6 * All Rights Reserved.
7 *
8 * Author Rickard E. (Rik) Faith <faith@valinux.com>
9 * Author Gareth Hughes <gareth@valinux.com>
10 *
11 * Permission is hereby granted, free of charge, to any person obtaining a
12 * copy of this software and associated documentation files (the "Software"),
13 * to deal in the Software without restriction, including without limitation
14 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
15 * and/or sell copies of the Software, and to permit persons to whom the
16 * Software is furnished to do so, subject to the following conditions:
17 *
18 * The above copyright notice and this permission notice (including the next
19 * paragraph) shall be included in all copies or substantial portions of the
20 * Software.
21 *
22 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
23 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
24 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
25 * VA LINUX SYSTEMS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
26 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
27 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
28 * OTHER DEALINGS IN THE SOFTWARE.
29 */
30
31 #include <linux/export.h>
32 #include <linux/nospec.h>
33 #include <linux/pci.h>
34 #include <linux/uaccess.h>
35
36 #include <drm/drm_auth.h>
37 #include <drm/drm_crtc.h>
38 #include <drm/drm_drv.h>
39 #include <drm/drm_file.h>
40 #include <drm/drm_ioctl.h>
41 #include <drm/drm_print.h>
42
43 #include "drm_crtc_internal.h"
44 #include "drm_internal.h"
45
46 /**
47 * DOC: getunique and setversion story
48 *
49 * BEWARE THE DRAGONS! MIND THE TRAPDOORS!
50 *
51 * In an attempt to warn anyone else who's trying to figure out what's going
52 * on here, I'll try to summarize the story. First things first, let's clear up
53 * the names, because the kernel internals, libdrm and the ioctls are all named
54 * differently:
55 *
56 * - GET_UNIQUE ioctl, implemented by drm_getunique is wrapped up in libdrm
57 * through the drmGetBusid function.
58 * - The libdrm drmSetBusid function is backed by the SET_UNIQUE ioctl. All
59 * that code is nerved in the kernel with drm_invalid_op().
60 * - The internal set_busid kernel functions and driver callbacks are
61 * exclusively use by the SET_VERSION ioctl, because only drm 1.0 (which is
62 * nerved) allowed userspace to set the busid through the above ioctl.
63 * - Other ioctls and functions involved are named consistently.
64 *
65 * For anyone wondering what's the difference between drm 1.1 and 1.4: Correctly
66 * handling pci domains in the busid on ppc. Doing this correctly was only
67 * implemented in libdrm in 2010, hence can't be nerved yet. No one knows what's
68 * special with drm 1.2 and 1.3.
69 *
70 * Now the actual horror story of how device lookup in drm works. At large,
71 * there's 2 different ways, either by busid, or by device driver name.
72 *
73 * Opening by busid is fairly simple:
74 *
75 * 1. First call SET_VERSION to make sure pci domains are handled properly. As a
76 * side-effect this fills out the unique name in the master structure.
77 * 2. Call GET_UNIQUE to read out the unique name from the master structure,
78 * which matches the busid thanks to step 1. If it doesn't, proceed to try
79 * the next device node.
80 *
81 * Opening by name is slightly different:
82 *
83 * 1. Directly call VERSION to get the version and to match against the driver
84 * name returned by that ioctl. Note that SET_VERSION is not called, which
85 * means the unique name for the master node just opening is _not_ filled
86 * out. This despite that with current drm device nodes are always bound to
87 * one device, and can't be runtime assigned like with drm 1.0.
88 * 2. Match driver name. If it mismatches, proceed to the next device node.
89 * 3. Call GET_UNIQUE, and check whether the unique name has length zero (by
90 * checking that the first byte in the string is 0). If that's not the case
91 * libdrm skips and proceeds to the next device node. Probably this is just
92 * copypasta from drm 1.0 times where a set unique name meant that the driver
93 * was in use already, but that's just conjecture.
94 *
95 * Long story short: To keep the open by name logic working, GET_UNIQUE must
96 * _not_ return a unique string when SET_VERSION hasn't been called yet,
97 * otherwise libdrm breaks. Even when that unique string can't ever change, and
98 * is totally irrelevant for actually opening the device because runtime
99 * assignable device instances were only support in drm 1.0, which is long dead.
100 * But the libdrm code in drmOpenByName somehow survived, hence this can't be
101 * broken.
102 */
103
104 /*
105 * Get the bus id.
106 *
107 * \param inode device inode.
108 * \param file_priv DRM file private.
109 * \param cmd command.
110 * \param arg user argument, pointing to a drm_unique structure.
111 * \return zero on success or a negative number on failure.
112 *
113 * Copies the bus id from drm_device::unique into user space.
114 */
drm_getunique(struct drm_device * dev,void * data,struct drm_file * file_priv)115 int drm_getunique(struct drm_device *dev, void *data,
116 struct drm_file *file_priv)
117 {
118 struct drm_unique *u = data;
119 struct drm_master *master;
120
121 mutex_lock(&dev->master_mutex);
122 master = file_priv->master;
123 if (u->unique_len >= master->unique_len) {
124 if (copy_to_user(u->unique, master->unique, master->unique_len)) {
125 mutex_unlock(&dev->master_mutex);
126 return -EFAULT;
127 }
128 }
129 u->unique_len = master->unique_len;
130 mutex_unlock(&dev->master_mutex);
131
132 return 0;
133 }
134
135 static void
drm_unset_busid(struct drm_device * dev,struct drm_master * master)136 drm_unset_busid(struct drm_device *dev,
137 struct drm_master *master)
138 {
139 kfree(master->unique);
140 master->unique = NULL;
141 master->unique_len = 0;
142 }
143
drm_set_busid(struct drm_device * dev,struct drm_file * file_priv)144 static int drm_set_busid(struct drm_device *dev, struct drm_file *file_priv)
145 {
146 struct drm_master *master = file_priv->master;
147 int ret;
148
149 if (master->unique != NULL)
150 drm_unset_busid(dev, master);
151
152 if (dev->dev && dev_is_pci(dev->dev)) {
153 ret = drm_pci_set_busid(dev, master);
154 if (ret) {
155 drm_unset_busid(dev, master);
156 return ret;
157 }
158 } else {
159 WARN_ON(!dev->unique);
160 master->unique = kstrdup(dev->unique, GFP_KERNEL);
161 if (master->unique)
162 master->unique_len = strlen(dev->unique);
163 }
164
165 return 0;
166 }
167
168 /*
169 * Get client information.
170 *
171 * \param inode device inode.
172 * \param file_priv DRM file private.
173 * \param cmd command.
174 * \param arg user argument, pointing to a drm_client structure.
175 *
176 * \return zero on success or a negative number on failure.
177 *
178 * Searches for the client with the specified index and copies its information
179 * into userspace
180 */
drm_getclient(struct drm_device * dev,void * data,struct drm_file * file_priv)181 int drm_getclient(struct drm_device *dev, void *data,
182 struct drm_file *file_priv)
183 {
184 struct drm_client *client = data;
185
186 /*
187 * Hollowed-out getclient ioctl to keep some dead old drm tests/tools
188 * not breaking completely. Userspace tools stop enumerating one they
189 * get -EINVAL, hence this is the return value we need to hand back for
190 * no clients tracked.
191 *
192 * Unfortunately some clients (*cough* libva *cough*) use this in a fun
193 * attempt to figure out whether they're authenticated or not. Since
194 * that's the only thing they care about, give it to the directly
195 * instead of walking one giant list.
196 */
197 if (client->idx == 0) {
198 client->auth = file_priv->authenticated;
199 client->pid = task_pid_vnr(current);
200 client->uid = overflowuid;
201 client->magic = 0;
202 client->iocs = 0;
203
204 return 0;
205 } else {
206 return -EINVAL;
207 }
208 }
209
210 /*
211 * Get statistics information.
212 *
213 * \param inode device inode.
214 * \param file_priv DRM file private.
215 * \param cmd command.
216 * \param arg user argument, pointing to a drm_stats structure.
217 *
218 * \return zero on success or a negative number on failure.
219 */
drm_getstats(struct drm_device * dev,void * data,struct drm_file * file_priv)220 static int drm_getstats(struct drm_device *dev, void *data,
221 struct drm_file *file_priv)
222 {
223 struct drm_stats *stats = data;
224
225 /* Clear stats to prevent userspace from eating its stack garbage. */
226 memset(stats, 0, sizeof(*stats));
227
228 return 0;
229 }
230
231 /*
232 * Get device/driver capabilities
233 */
drm_getcap(struct drm_device * dev,void * data,struct drm_file * file_priv)234 static int drm_getcap(struct drm_device *dev, void *data, struct drm_file *file_priv)
235 {
236 struct drm_get_cap *req = data;
237 struct drm_crtc *crtc;
238
239 req->value = 0;
240
241 /* Only some caps make sense with UMS/render-only drivers. */
242 switch (req->capability) {
243 case DRM_CAP_TIMESTAMP_MONOTONIC:
244 req->value = 1;
245 return 0;
246 case DRM_CAP_PRIME:
247 req->value = DRM_PRIME_CAP_IMPORT | DRM_PRIME_CAP_EXPORT;
248 return 0;
249 case DRM_CAP_SYNCOBJ:
250 req->value = drm_core_check_feature(dev, DRIVER_SYNCOBJ);
251 return 0;
252 case DRM_CAP_SYNCOBJ_TIMELINE:
253 req->value = drm_core_check_feature(dev, DRIVER_SYNCOBJ_TIMELINE);
254 return 0;
255 }
256
257 /* Other caps only work with KMS drivers */
258 if (!drm_core_check_feature(dev, DRIVER_MODESET))
259 return -EOPNOTSUPP;
260
261 switch (req->capability) {
262 case DRM_CAP_DUMB_BUFFER:
263 if (dev->driver->dumb_create)
264 req->value = 1;
265 break;
266 case DRM_CAP_VBLANK_HIGH_CRTC:
267 req->value = 1;
268 break;
269 case DRM_CAP_DUMB_PREFERRED_DEPTH:
270 req->value = dev->mode_config.preferred_depth;
271 break;
272 case DRM_CAP_DUMB_PREFER_SHADOW:
273 req->value = dev->mode_config.prefer_shadow;
274 break;
275 case DRM_CAP_ASYNC_PAGE_FLIP:
276 req->value = dev->mode_config.async_page_flip;
277 break;
278 case DRM_CAP_PAGE_FLIP_TARGET:
279 req->value = 1;
280 drm_for_each_crtc(crtc, dev) {
281 if (!crtc->funcs->page_flip_target)
282 req->value = 0;
283 }
284 break;
285 case DRM_CAP_CURSOR_WIDTH:
286 if (dev->mode_config.cursor_width)
287 req->value = dev->mode_config.cursor_width;
288 else
289 req->value = 64;
290 break;
291 case DRM_CAP_CURSOR_HEIGHT:
292 if (dev->mode_config.cursor_height)
293 req->value = dev->mode_config.cursor_height;
294 else
295 req->value = 64;
296 break;
297 case DRM_CAP_ADDFB2_MODIFIERS:
298 req->value = !dev->mode_config.fb_modifiers_not_supported;
299 break;
300 case DRM_CAP_CRTC_IN_VBLANK_EVENT:
301 req->value = 1;
302 break;
303 case DRM_CAP_ATOMIC_ASYNC_PAGE_FLIP:
304 req->value = drm_core_check_feature(dev, DRIVER_ATOMIC) &&
305 dev->mode_config.async_page_flip;
306 break;
307 default:
308 return -EINVAL;
309 }
310 return 0;
311 }
312
313 /*
314 * Set device/driver capabilities
315 */
316 static int
drm_setclientcap(struct drm_device * dev,void * data,struct drm_file * file_priv)317 drm_setclientcap(struct drm_device *dev, void *data, struct drm_file *file_priv)
318 {
319 struct drm_set_client_cap *req = data;
320
321 /* No render-only settable capabilities for now */
322
323 /* Below caps that only works with KMS drivers */
324 if (!drm_core_check_feature(dev, DRIVER_MODESET))
325 return -EOPNOTSUPP;
326
327 switch (req->capability) {
328 case DRM_CLIENT_CAP_STEREO_3D:
329 if (req->value > 1)
330 return -EINVAL;
331 file_priv->stereo_allowed = req->value;
332 break;
333 case DRM_CLIENT_CAP_UNIVERSAL_PLANES:
334 if (req->value > 1)
335 return -EINVAL;
336 file_priv->universal_planes = req->value;
337 break;
338 case DRM_CLIENT_CAP_ATOMIC:
339 if (!drm_core_check_feature(dev, DRIVER_ATOMIC))
340 return -EOPNOTSUPP;
341 /* The modesetting DDX has a totally broken idea of atomic. */
342 if (current->comm[0] == 'X' && req->value == 1) {
343 pr_info("broken atomic modeset userspace detected, disabling atomic\n");
344 return -EOPNOTSUPP;
345 }
346 if (req->value > 2)
347 return -EINVAL;
348 file_priv->atomic = req->value;
349 file_priv->universal_planes = req->value;
350 /*
351 * No atomic user-space blows up on aspect ratio mode bits.
352 */
353 file_priv->aspect_ratio_allowed = req->value;
354 break;
355 case DRM_CLIENT_CAP_ASPECT_RATIO:
356 if (req->value > 1)
357 return -EINVAL;
358 file_priv->aspect_ratio_allowed = req->value;
359 break;
360 case DRM_CLIENT_CAP_WRITEBACK_CONNECTORS:
361 if (!file_priv->atomic)
362 return -EINVAL;
363 if (req->value > 1)
364 return -EINVAL;
365 file_priv->writeback_connectors = req->value;
366 break;
367 case DRM_CLIENT_CAP_CURSOR_PLANE_HOTSPOT:
368 if (!drm_core_check_feature(dev, DRIVER_CURSOR_HOTSPOT))
369 return -EOPNOTSUPP;
370 if (!file_priv->atomic)
371 return -EINVAL;
372 if (req->value > 1)
373 return -EINVAL;
374 file_priv->supports_virtualized_cursor_plane = req->value;
375 break;
376 case DRM_CLIENT_CAP_PLANE_COLOR_PIPELINE:
377 if (!file_priv->atomic)
378 return -EINVAL;
379 if (req->value > 1)
380 return -EINVAL;
381 file_priv->plane_color_pipeline = req->value;
382 break;
383 default:
384 return -EINVAL;
385 }
386
387 return 0;
388 }
389
390 /*
391 * Setversion ioctl.
392 *
393 * \param inode device inode.
394 * \param file_priv DRM file private.
395 * \param cmd command.
396 * \param arg user argument, pointing to a drm_lock structure.
397 * \return zero on success or negative number on failure.
398 *
399 * Sets the requested interface version
400 */
drm_setversion(struct drm_device * dev,void * data,struct drm_file * file_priv)401 static int drm_setversion(struct drm_device *dev, void *data, struct drm_file *file_priv)
402 {
403 struct drm_set_version *sv = data;
404 int if_version, retcode = 0;
405
406 mutex_lock(&dev->master_mutex);
407 if (sv->drm_di_major != -1) {
408 if (sv->drm_di_major != DRM_IF_MAJOR ||
409 sv->drm_di_minor < 0 || sv->drm_di_minor > DRM_IF_MINOR) {
410 retcode = -EINVAL;
411 goto done;
412 }
413 if_version = DRM_IF_VERSION(sv->drm_di_major,
414 sv->drm_di_minor);
415 dev->if_version = max(if_version, dev->if_version);
416 if (sv->drm_di_minor >= 1) {
417 /*
418 * Version 1.1 includes tying of DRM to specific device
419 * Version 1.4 has proper PCI domain support
420 */
421 retcode = drm_set_busid(dev, file_priv);
422 if (retcode)
423 goto done;
424 }
425 }
426
427 if (sv->drm_dd_major != -1) {
428 if (sv->drm_dd_major != dev->driver->major ||
429 sv->drm_dd_minor < 0 || sv->drm_dd_minor >
430 dev->driver->minor) {
431 retcode = -EINVAL;
432 goto done;
433 }
434 }
435
436 done:
437 sv->drm_di_major = DRM_IF_MAJOR;
438 sv->drm_di_minor = DRM_IF_MINOR;
439 sv->drm_dd_major = dev->driver->major;
440 sv->drm_dd_minor = dev->driver->minor;
441 mutex_unlock(&dev->master_mutex);
442
443 return retcode;
444 }
445
446 /**
447 * drm_noop - DRM no-op ioctl implementation
448 * @dev: DRM device for the ioctl
449 * @data: data pointer for the ioctl
450 * @file_priv: DRM file for the ioctl call
451 *
452 * This no-op implementation for drm ioctls is useful for deprecated
453 * functionality where we can't return a failure code because existing userspace
454 * checks the result of the ioctl, but doesn't care about the action.
455 *
456 * Always returns successfully with 0.
457 */
drm_noop(struct drm_device * dev,void * data,struct drm_file * file_priv)458 int drm_noop(struct drm_device *dev, void *data,
459 struct drm_file *file_priv)
460 {
461 drm_dbg_core(dev, "\n");
462 return 0;
463 }
464 EXPORT_SYMBOL(drm_noop);
465
466 /**
467 * drm_invalid_op - DRM invalid ioctl implementation
468 * @dev: DRM device for the ioctl
469 * @data: data pointer for the ioctl
470 * @file_priv: DRM file for the ioctl call
471 *
472 * This no-op implementation for drm ioctls is useful for deprecated
473 * functionality where we really don't want to allow userspace to call the ioctl
474 * any more. This is the case for old ums interfaces for drivers that
475 * transitioned to kms gradually and so kept the old legacy tables around. This
476 * only applies to radeon and i915 kms drivers, other drivers shouldn't need to
477 * use this function.
478 *
479 * Always fails with a return value of -EINVAL.
480 */
drm_invalid_op(struct drm_device * dev,void * data,struct drm_file * file_priv)481 int drm_invalid_op(struct drm_device *dev, void *data,
482 struct drm_file *file_priv)
483 {
484 return -EINVAL;
485 }
486 EXPORT_SYMBOL(drm_invalid_op);
487
488 /*
489 * Copy and IOCTL return string to user space
490 */
drm_copy_field(char __user * buf,size_t * buf_len,const char * value)491 static int drm_copy_field(char __user *buf, size_t *buf_len, const char *value)
492 {
493 size_t len;
494
495 /* don't attempt to copy a NULL pointer */
496 if (WARN_ONCE(!value, "BUG: the value to copy was not set!")) {
497 *buf_len = 0;
498 return 0;
499 }
500
501 /* don't overflow userbuf */
502 len = strlen(value);
503 if (len > *buf_len)
504 len = *buf_len;
505
506 /* let userspace know exact length of driver value (which could be
507 * larger than the userspace-supplied buffer) */
508 *buf_len = strlen(value);
509
510 /* finally, try filling in the userbuf */
511 if (len && buf)
512 if (copy_to_user(buf, value, len))
513 return -EFAULT;
514 return 0;
515 }
516
517 /*
518 * Get version information
519 *
520 * \param inode device inode.
521 * \param filp file pointer.
522 * \param cmd command.
523 * \param arg user argument, pointing to a drm_version structure.
524 * \return zero on success or negative number on failure.
525 *
526 * Fills in the version information in \p arg.
527 */
drm_version(struct drm_device * dev,void * data,struct drm_file * file_priv)528 int drm_version(struct drm_device *dev, void *data,
529 struct drm_file *file_priv)
530 {
531 struct drm_version *version = data;
532 int err;
533
534 version->version_major = dev->driver->major;
535 version->version_minor = dev->driver->minor;
536 version->version_patchlevel = dev->driver->patchlevel;
537 err = drm_copy_field(version->name, &version->name_len,
538 dev->driver->name);
539
540 /* Driver date is deprecated. Userspace expects a non-empty string. */
541 if (!err)
542 err = drm_copy_field(version->date, &version->date_len, "0");
543 if (!err)
544 err = drm_copy_field(version->desc, &version->desc_len,
545 dev->driver->desc);
546
547 return err;
548 }
549
550 /*
551 * Check if the passed string contains control char or spaces or
552 * anything that would mess up a formatted output.
553 */
drm_validate_value_string(const char * value,size_t len)554 static int drm_validate_value_string(const char *value, size_t len)
555 {
556 int i;
557
558 for (i = 0; i < len; i++) {
559 if (!isascii(value[i]) || !isgraph(value[i]))
560 return -EINVAL;
561 }
562 return 0;
563 }
564
drm_set_client_name(struct drm_device * dev,void * data,struct drm_file * file_priv)565 static int drm_set_client_name(struct drm_device *dev, void *data,
566 struct drm_file *file_priv)
567 {
568 struct drm_set_client_name *name = data;
569 size_t len = name->name_len;
570 void __user *user_ptr;
571 char *new_name;
572
573 if (len > DRM_CLIENT_NAME_MAX_LEN) {
574 return -EINVAL;
575 } else if (len) {
576 user_ptr = u64_to_user_ptr(name->name);
577
578 new_name = memdup_user_nul(user_ptr, len);
579 if (IS_ERR(new_name))
580 return PTR_ERR(new_name);
581
582 if (strlen(new_name) != len ||
583 drm_validate_value_string(new_name, len) < 0) {
584 kfree(new_name);
585 return -EINVAL;
586 }
587 } else {
588 new_name = NULL;
589 }
590
591 mutex_lock(&file_priv->client_name_lock);
592 kfree(file_priv->client_name);
593 file_priv->client_name = new_name;
594 mutex_unlock(&file_priv->client_name_lock);
595
596 return 0;
597 }
598
drm_ioctl_permit(u32 flags,struct drm_file * file_priv)599 static int drm_ioctl_permit(u32 flags, struct drm_file *file_priv)
600 {
601 /* ROOT_ONLY is only for CAP_SYS_ADMIN */
602 if (unlikely((flags & DRM_ROOT_ONLY) && !capable(CAP_SYS_ADMIN)))
603 return -EACCES;
604
605 /* AUTH is only for authenticated or render client */
606 if (unlikely((flags & DRM_AUTH) && !drm_is_render_client(file_priv) &&
607 !file_priv->authenticated))
608 return -EACCES;
609
610 /* MASTER is only for master or control clients */
611 if (unlikely((flags & DRM_MASTER) &&
612 !drm_is_current_master(file_priv)))
613 return -EACCES;
614
615 /* Render clients must be explicitly allowed */
616 if (unlikely(!(flags & DRM_RENDER_ALLOW) &&
617 drm_is_render_client(file_priv)))
618 return -EACCES;
619
620 return 0;
621 }
622
623 #define DRM_IOCTL_DEF(ioctl, _func, _flags) \
624 [DRM_IOCTL_NR(ioctl)] = { \
625 .cmd = ioctl, \
626 .func = _func, \
627 .flags = _flags, \
628 .name = #ioctl \
629 }
630
631 /* Ioctl table */
632 static const struct drm_ioctl_desc drm_ioctls[] = {
633 DRM_IOCTL_DEF(DRM_IOCTL_VERSION, drm_version, DRM_RENDER_ALLOW),
634 DRM_IOCTL_DEF(DRM_IOCTL_GET_UNIQUE, drm_getunique, 0),
635 DRM_IOCTL_DEF(DRM_IOCTL_GET_MAGIC, drm_getmagic, 0),
636
637 DRM_IOCTL_DEF(DRM_IOCTL_GET_CLIENT, drm_getclient, 0),
638 DRM_IOCTL_DEF(DRM_IOCTL_GET_STATS, drm_getstats, 0),
639 DRM_IOCTL_DEF(DRM_IOCTL_GET_CAP, drm_getcap, DRM_RENDER_ALLOW),
640 DRM_IOCTL_DEF(DRM_IOCTL_SET_CLIENT_CAP, drm_setclientcap, 0),
641 DRM_IOCTL_DEF(DRM_IOCTL_SET_VERSION, drm_setversion, DRM_MASTER),
642
643 DRM_IOCTL_DEF(DRM_IOCTL_SET_UNIQUE, drm_invalid_op, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
644 DRM_IOCTL_DEF(DRM_IOCTL_BLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
645 DRM_IOCTL_DEF(DRM_IOCTL_UNBLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
646 DRM_IOCTL_DEF(DRM_IOCTL_AUTH_MAGIC, drm_authmagic, DRM_MASTER),
647
648 DRM_IOCTL_DEF(DRM_IOCTL_SET_MASTER, drm_setmaster_ioctl, 0),
649 DRM_IOCTL_DEF(DRM_IOCTL_DROP_MASTER, drm_dropmaster_ioctl, 0),
650
651 DRM_IOCTL_DEF(DRM_IOCTL_ADD_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
652 DRM_IOCTL_DEF(DRM_IOCTL_RM_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
653
654 DRM_IOCTL_DEF(DRM_IOCTL_FINISH, drm_noop, DRM_AUTH),
655
656 DRM_IOCTL_DEF(DRM_IOCTL_WAIT_VBLANK, drm_wait_vblank_ioctl, 0),
657
658 DRM_IOCTL_DEF(DRM_IOCTL_UPDATE_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
659
660 DRM_IOCTL_DEF(DRM_IOCTL_GEM_CLOSE, drm_gem_close_ioctl, DRM_RENDER_ALLOW),
661 DRM_IOCTL_DEF(DRM_IOCTL_GEM_FLINK, drm_gem_flink_ioctl, DRM_AUTH),
662 DRM_IOCTL_DEF(DRM_IOCTL_GEM_OPEN, drm_gem_open_ioctl, DRM_AUTH),
663 DRM_IOCTL_DEF(DRM_IOCTL_GEM_CHANGE_HANDLE, drm_gem_change_handle_ioctl, DRM_RENDER_ALLOW),
664
665 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETRESOURCES, drm_mode_getresources, 0),
666
667 DRM_IOCTL_DEF(DRM_IOCTL_PRIME_HANDLE_TO_FD, drm_prime_handle_to_fd_ioctl, DRM_RENDER_ALLOW),
668 DRM_IOCTL_DEF(DRM_IOCTL_PRIME_FD_TO_HANDLE, drm_prime_fd_to_handle_ioctl, DRM_RENDER_ALLOW),
669
670 DRM_IOCTL_DEF(DRM_IOCTL_SET_CLIENT_NAME, drm_set_client_name, DRM_RENDER_ALLOW),
671
672 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPLANERESOURCES, drm_mode_getplane_res, 0),
673 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCRTC, drm_mode_getcrtc, 0),
674 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETCRTC, drm_mode_setcrtc, DRM_MASTER),
675 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPLANE, drm_mode_getplane, 0),
676 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETPLANE, drm_mode_setplane, DRM_MASTER),
677 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CURSOR, drm_mode_cursor_ioctl, DRM_MASTER),
678 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETGAMMA, drm_mode_gamma_get_ioctl, 0),
679 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETGAMMA, drm_mode_gamma_set_ioctl, DRM_MASTER),
680 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETENCODER, drm_mode_getencoder, 0),
681 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCONNECTOR, drm_mode_getconnector, 0),
682 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ATTACHMODE, drm_noop, DRM_MASTER),
683 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DETACHMODE, drm_noop, DRM_MASTER),
684 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPERTY, drm_mode_getproperty_ioctl, 0),
685 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETPROPERTY, drm_connector_property_set_ioctl, DRM_MASTER),
686 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPBLOB, drm_mode_getblob_ioctl, 0),
687 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETFB, drm_mode_getfb, 0),
688 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETFB2, drm_mode_getfb2_ioctl, 0),
689 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB, drm_mode_addfb_ioctl, 0),
690 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB2, drm_mode_addfb2_ioctl, 0),
691 DRM_IOCTL_DEF(DRM_IOCTL_MODE_RMFB, drm_mode_rmfb_ioctl, 0),
692 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CLOSEFB, drm_mode_closefb_ioctl, 0),
693 DRM_IOCTL_DEF(DRM_IOCTL_MODE_PAGE_FLIP, drm_mode_page_flip_ioctl, DRM_MASTER),
694 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DIRTYFB, drm_mode_dirtyfb_ioctl, DRM_MASTER),
695 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATE_DUMB, drm_mode_create_dumb_ioctl, 0),
696 DRM_IOCTL_DEF(DRM_IOCTL_MODE_MAP_DUMB, drm_mode_mmap_dumb_ioctl, 0),
697 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DESTROY_DUMB, drm_mode_destroy_dumb_ioctl, 0),
698 DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_GETPROPERTIES, drm_mode_obj_get_properties_ioctl, 0),
699 DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_SETPROPERTY, drm_mode_obj_set_property_ioctl, DRM_MASTER),
700 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CURSOR2, drm_mode_cursor2_ioctl, DRM_MASTER),
701 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ATOMIC, drm_mode_atomic_ioctl, DRM_MASTER),
702 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATEPROPBLOB, drm_mode_createblob_ioctl, 0),
703 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DESTROYPROPBLOB, drm_mode_destroyblob_ioctl, 0),
704
705 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_CREATE, drm_syncobj_create_ioctl,
706 DRM_RENDER_ALLOW),
707 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_DESTROY, drm_syncobj_destroy_ioctl,
708 DRM_RENDER_ALLOW),
709 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_HANDLE_TO_FD, drm_syncobj_handle_to_fd_ioctl,
710 DRM_RENDER_ALLOW),
711 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_FD_TO_HANDLE, drm_syncobj_fd_to_handle_ioctl,
712 DRM_RENDER_ALLOW),
713 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_TRANSFER, drm_syncobj_transfer_ioctl,
714 DRM_RENDER_ALLOW),
715 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_WAIT, drm_syncobj_wait_ioctl,
716 DRM_RENDER_ALLOW),
717 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_TIMELINE_WAIT, drm_syncobj_timeline_wait_ioctl,
718 DRM_RENDER_ALLOW),
719 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_EVENTFD, drm_syncobj_eventfd_ioctl,
720 DRM_RENDER_ALLOW),
721 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_RESET, drm_syncobj_reset_ioctl,
722 DRM_RENDER_ALLOW),
723 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_SIGNAL, drm_syncobj_signal_ioctl,
724 DRM_RENDER_ALLOW),
725 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_TIMELINE_SIGNAL, drm_syncobj_timeline_signal_ioctl,
726 DRM_RENDER_ALLOW),
727 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_QUERY, drm_syncobj_query_ioctl,
728 DRM_RENDER_ALLOW),
729 DRM_IOCTL_DEF(DRM_IOCTL_CRTC_GET_SEQUENCE, drm_crtc_get_sequence_ioctl, 0),
730 DRM_IOCTL_DEF(DRM_IOCTL_CRTC_QUEUE_SEQUENCE, drm_crtc_queue_sequence_ioctl, 0),
731 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATE_LEASE, drm_mode_create_lease_ioctl, DRM_MASTER),
732 DRM_IOCTL_DEF(DRM_IOCTL_MODE_LIST_LESSEES, drm_mode_list_lessees_ioctl, DRM_MASTER),
733 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GET_LEASE, drm_mode_get_lease_ioctl, DRM_MASTER),
734 DRM_IOCTL_DEF(DRM_IOCTL_MODE_REVOKE_LEASE, drm_mode_revoke_lease_ioctl, DRM_MASTER),
735 };
736
737 #define DRM_CORE_IOCTL_COUNT ARRAY_SIZE(drm_ioctls)
738
739 /**
740 * DOC: driver specific ioctls
741 *
742 * First things first, driver private IOCTLs should only be needed for drivers
743 * supporting rendering. Kernel modesetting is all standardized, and extended
744 * through properties. There are a few exceptions in some existing drivers,
745 * which define IOCTL for use by the display DRM master, but they all predate
746 * properties.
747 *
748 * Now if you do have a render driver you always have to support it through
749 * driver private properties. There's a few steps needed to wire all the things
750 * up.
751 *
752 * First you need to define the structure for your IOCTL in your driver private
753 * UAPI header in ``include/uapi/drm/my_driver_drm.h``::
754 *
755 * struct my_driver_operation {
756 * u32 some_thing;
757 * u32 another_thing;
758 * };
759 *
760 * Please make sure that you follow all the best practices from
761 * ``Documentation/process/botching-up-ioctls.rst``. Note that drm_ioctl()
762 * automatically zero-extends structures, hence make sure you can add more stuff
763 * at the end, i.e. don't put a variable sized array there.
764 *
765 * Then you need to define your IOCTL number, using one of DRM_IO(), DRM_IOR(),
766 * DRM_IOW() or DRM_IOWR(). It must start with the DRM_IOCTL\_ prefix::
767 *
768 * ##define DRM_IOCTL_MY_DRIVER_OPERATION \
769 * DRM_IOW(DRM_COMMAND_BASE, struct my_driver_operation)
770 *
771 * DRM driver private IOCTL must be in the range from DRM_COMMAND_BASE to
772 * DRM_COMMAND_END. Finally you need an array of &struct drm_ioctl_desc to wire
773 * up the handlers and set the access rights::
774 *
775 * static const struct drm_ioctl_desc my_driver_ioctls[] = {
776 * DRM_IOCTL_DEF_DRV(MY_DRIVER_OPERATION, my_driver_operation,
777 * DRM_AUTH|DRM_RENDER_ALLOW),
778 * };
779 *
780 * And then assign this to the &drm_driver.ioctls field in your driver
781 * structure.
782 *
783 * See the separate chapter on :ref:`file operations<drm_driver_fops>` for how
784 * the driver-specific IOCTLs are wired up.
785 */
786
drm_ioctl_kernel(struct file * file,drm_ioctl_t * func,void * kdata,u32 flags)787 long drm_ioctl_kernel(struct file *file, drm_ioctl_t *func, void *kdata,
788 u32 flags)
789 {
790 struct drm_file *file_priv = file->private_data;
791 struct drm_device *dev = file_priv->minor->dev;
792 int ret;
793
794 /* Update drm_file owner if fd was passed along. */
795 drm_file_update_pid(file_priv);
796
797 if (drm_dev_is_unplugged(dev))
798 return -ENODEV;
799
800 ret = drm_ioctl_permit(flags, file_priv);
801 if (unlikely(ret))
802 return ret;
803
804 return func(dev, kdata, file_priv);
805 }
806 EXPORT_SYMBOL(drm_ioctl_kernel);
807
808 /**
809 * drm_ioctl - ioctl callback implementation for DRM drivers
810 * @filp: file this ioctl is called on
811 * @cmd: ioctl cmd number
812 * @arg: user argument
813 *
814 * Looks up the ioctl function in the DRM core and the driver dispatch table,
815 * stored in &drm_driver.ioctls. It checks for necessary permission by calling
816 * drm_ioctl_permit(), and dispatches to the respective function.
817 *
818 * Returns:
819 * Zero on success, negative error code on failure.
820 */
drm_ioctl(struct file * filp,unsigned int cmd,unsigned long arg)821 long drm_ioctl(struct file *filp,
822 unsigned int cmd, unsigned long arg)
823 {
824 struct drm_file *file_priv = filp->private_data;
825 struct drm_device *dev;
826 const struct drm_ioctl_desc *ioctl = NULL;
827 drm_ioctl_t *func;
828 unsigned int nr = DRM_IOCTL_NR(cmd);
829 int retcode = -EINVAL;
830 char stack_kdata[128];
831 char *kdata = NULL;
832 unsigned int in_size, out_size, drv_size, ksize;
833 bool is_driver_ioctl;
834
835 dev = file_priv->minor->dev;
836
837 if (drm_dev_is_unplugged(dev))
838 return -ENODEV;
839
840 if (DRM_IOCTL_TYPE(cmd) != DRM_IOCTL_BASE)
841 return -ENOTTY;
842
843 is_driver_ioctl = nr >= DRM_COMMAND_BASE && nr < DRM_COMMAND_END;
844
845 if (is_driver_ioctl) {
846 /* driver ioctl */
847 unsigned int index = nr - DRM_COMMAND_BASE;
848
849 if (index >= dev->driver->num_ioctls)
850 goto err_i1;
851 index = array_index_nospec(index, dev->driver->num_ioctls);
852 ioctl = &dev->driver->ioctls[index];
853 } else {
854 /* core ioctl */
855 if (nr >= DRM_CORE_IOCTL_COUNT)
856 goto err_i1;
857 nr = array_index_nospec(nr, DRM_CORE_IOCTL_COUNT);
858 ioctl = &drm_ioctls[nr];
859 }
860
861 drv_size = _IOC_SIZE(ioctl->cmd);
862 out_size = in_size = _IOC_SIZE(cmd);
863 if ((cmd & ioctl->cmd & IOC_IN) == 0)
864 in_size = 0;
865 if ((cmd & ioctl->cmd & IOC_OUT) == 0)
866 out_size = 0;
867 ksize = max(max(in_size, out_size), drv_size);
868
869 drm_dbg_core(dev, "comm=\"%s\" pid=%d, dev=0x%lx, auth=%d, %s\n",
870 current->comm, task_pid_nr(current),
871 (long)old_encode_dev(file_priv->minor->kdev->devt),
872 file_priv->authenticated, ioctl->name);
873
874 /* Do not trust userspace, use our own definition */
875 func = ioctl->func;
876
877 if (unlikely(!func)) {
878 drm_dbg_core(dev, "no function\n");
879 retcode = -EINVAL;
880 goto err_i1;
881 }
882
883 if (ksize <= sizeof(stack_kdata)) {
884 kdata = stack_kdata;
885 } else {
886 kdata = kmalloc(ksize, GFP_KERNEL);
887 if (!kdata) {
888 retcode = -ENOMEM;
889 goto err_i1;
890 }
891 }
892
893 if (copy_from_user(kdata, (void __user *)arg, in_size) != 0) {
894 retcode = -EFAULT;
895 goto err_i1;
896 }
897
898 if (ksize > in_size)
899 memset(kdata + in_size, 0, ksize - in_size);
900
901 retcode = drm_ioctl_kernel(filp, func, kdata, ioctl->flags);
902 if (copy_to_user((void __user *)arg, kdata, out_size) != 0)
903 retcode = -EFAULT;
904
905 err_i1:
906 if (!ioctl)
907 drm_dbg_core(dev,
908 "invalid ioctl: comm=\"%s\", pid=%d, dev=0x%lx, auth=%d, cmd=0x%02x, nr=0x%02x\n",
909 current->comm, task_pid_nr(current),
910 (long)old_encode_dev(file_priv->minor->kdev->devt),
911 file_priv->authenticated, cmd, nr);
912
913 if (kdata != stack_kdata)
914 kfree(kdata);
915 if (retcode)
916 drm_dbg_core(dev, "comm=\"%s\", pid=%d, ret=%d\n",
917 current->comm, task_pid_nr(current), retcode);
918 return retcode;
919 }
920 EXPORT_SYMBOL(drm_ioctl);
921
922 /**
923 * drm_ioctl_flags - Check for core ioctl and return ioctl permission flags
924 * @nr: ioctl number
925 * @flags: where to return the ioctl permission flags
926 *
927 * This ioctl is only used by the vmwgfx driver to augment the access checks
928 * done by the drm core and insofar a pretty decent layering violation. This
929 * shouldn't be used by any drivers.
930 *
931 * Returns:
932 * True if the @nr corresponds to a DRM core ioctl number, false otherwise.
933 */
drm_ioctl_flags(unsigned int nr,unsigned int * flags)934 bool drm_ioctl_flags(unsigned int nr, unsigned int *flags)
935 {
936 if (nr >= DRM_COMMAND_BASE && nr < DRM_COMMAND_END)
937 return false;
938
939 if (nr >= DRM_CORE_IOCTL_COUNT)
940 return false;
941 nr = array_index_nospec(nr, DRM_CORE_IOCTL_COUNT);
942
943 *flags = drm_ioctls[nr].flags;
944 return true;
945 }
946 EXPORT_SYMBOL(drm_ioctl_flags);
947