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 struct drm_plane *plane;
378 bool has_plane_with_color_pipeline = false;
379
380 if (!file_priv->atomic)
381 return -EINVAL;
382 if (req->value > 1)
383 return -EINVAL;
384 drm_for_each_plane(plane, dev) {
385 if (plane->color_pipeline_property) {
386 has_plane_with_color_pipeline = true;
387 break;
388 }
389 }
390 if (!has_plane_with_color_pipeline)
391 return -EOPNOTSUPP;
392 file_priv->plane_color_pipeline = req->value;
393 break;
394 }
395 default:
396 return -EINVAL;
397 }
398
399 return 0;
400 }
401
402 /*
403 * Setversion ioctl.
404 *
405 * \param inode device inode.
406 * \param file_priv DRM file private.
407 * \param cmd command.
408 * \param arg user argument, pointing to a drm_lock structure.
409 * \return zero on success or negative number on failure.
410 *
411 * Sets the requested interface version
412 */
drm_setversion(struct drm_device * dev,void * data,struct drm_file * file_priv)413 static int drm_setversion(struct drm_device *dev, void *data, struct drm_file *file_priv)
414 {
415 struct drm_set_version *sv = data;
416 int if_version, retcode = 0;
417
418 mutex_lock(&dev->master_mutex);
419 if (sv->drm_di_major != -1) {
420 if (sv->drm_di_major != DRM_IF_MAJOR ||
421 sv->drm_di_minor < 0 || sv->drm_di_minor > DRM_IF_MINOR) {
422 retcode = -EINVAL;
423 goto done;
424 }
425 if_version = DRM_IF_VERSION(sv->drm_di_major,
426 sv->drm_di_minor);
427 dev->if_version = max(if_version, dev->if_version);
428 if (sv->drm_di_minor >= 1) {
429 /*
430 * Version 1.1 includes tying of DRM to specific device
431 * Version 1.4 has proper PCI domain support
432 */
433 retcode = drm_set_busid(dev, file_priv);
434 if (retcode)
435 goto done;
436 }
437 }
438
439 if (sv->drm_dd_major != -1) {
440 if (sv->drm_dd_major != dev->driver->major ||
441 sv->drm_dd_minor < 0 || sv->drm_dd_minor >
442 dev->driver->minor) {
443 retcode = -EINVAL;
444 goto done;
445 }
446 }
447
448 done:
449 sv->drm_di_major = DRM_IF_MAJOR;
450 sv->drm_di_minor = DRM_IF_MINOR;
451 sv->drm_dd_major = dev->driver->major;
452 sv->drm_dd_minor = dev->driver->minor;
453 mutex_unlock(&dev->master_mutex);
454
455 return retcode;
456 }
457
458 /**
459 * drm_noop - DRM no-op ioctl implementation
460 * @dev: DRM device for the ioctl
461 * @data: data pointer for the ioctl
462 * @file_priv: DRM file for the ioctl call
463 *
464 * This no-op implementation for drm ioctls is useful for deprecated
465 * functionality where we can't return a failure code because existing userspace
466 * checks the result of the ioctl, but doesn't care about the action.
467 *
468 * Always returns successfully with 0.
469 */
drm_noop(struct drm_device * dev,void * data,struct drm_file * file_priv)470 int drm_noop(struct drm_device *dev, void *data,
471 struct drm_file *file_priv)
472 {
473 drm_dbg_core(dev, "\n");
474 return 0;
475 }
476 EXPORT_SYMBOL(drm_noop);
477
478 /**
479 * drm_invalid_op - DRM invalid ioctl implementation
480 * @dev: DRM device for the ioctl
481 * @data: data pointer for the ioctl
482 * @file_priv: DRM file for the ioctl call
483 *
484 * This no-op implementation for drm ioctls is useful for deprecated
485 * functionality where we really don't want to allow userspace to call the ioctl
486 * any more. This is the case for old ums interfaces for drivers that
487 * transitioned to kms gradually and so kept the old legacy tables around. This
488 * only applies to radeon and i915 kms drivers, other drivers shouldn't need to
489 * use this function.
490 *
491 * Always fails with a return value of -EINVAL.
492 */
drm_invalid_op(struct drm_device * dev,void * data,struct drm_file * file_priv)493 int drm_invalid_op(struct drm_device *dev, void *data,
494 struct drm_file *file_priv)
495 {
496 return -EINVAL;
497 }
498 EXPORT_SYMBOL(drm_invalid_op);
499
500 /*
501 * Copy and IOCTL return string to user space
502 */
drm_copy_field(char __user * buf,size_t * buf_len,const char * value)503 static int drm_copy_field(char __user *buf, size_t *buf_len, const char *value)
504 {
505 size_t len;
506
507 /* don't attempt to copy a NULL pointer */
508 if (WARN_ONCE(!value, "BUG: the value to copy was not set!")) {
509 *buf_len = 0;
510 return 0;
511 }
512
513 /* don't overflow userbuf */
514 len = strlen(value);
515 if (len > *buf_len)
516 len = *buf_len;
517
518 /* let userspace know exact length of driver value (which could be
519 * larger than the userspace-supplied buffer) */
520 *buf_len = strlen(value);
521
522 /* finally, try filling in the userbuf */
523 if (len && buf)
524 if (copy_to_user(buf, value, len))
525 return -EFAULT;
526 return 0;
527 }
528
529 /*
530 * Get version information
531 *
532 * \param inode device inode.
533 * \param filp file pointer.
534 * \param cmd command.
535 * \param arg user argument, pointing to a drm_version structure.
536 * \return zero on success or negative number on failure.
537 *
538 * Fills in the version information in \p arg.
539 */
drm_version(struct drm_device * dev,void * data,struct drm_file * file_priv)540 int drm_version(struct drm_device *dev, void *data,
541 struct drm_file *file_priv)
542 {
543 struct drm_version *version = data;
544 int err;
545
546 version->version_major = dev->driver->major;
547 version->version_minor = dev->driver->minor;
548 version->version_patchlevel = dev->driver->patchlevel;
549 err = drm_copy_field(version->name, &version->name_len,
550 dev->driver->name);
551
552 /* Driver date is deprecated. Userspace expects a non-empty string. */
553 if (!err)
554 err = drm_copy_field(version->date, &version->date_len, "0");
555 if (!err)
556 err = drm_copy_field(version->desc, &version->desc_len,
557 dev->driver->desc);
558
559 return err;
560 }
561
562 /*
563 * Check if the passed string contains control char or spaces or
564 * anything that would mess up a formatted output.
565 */
drm_validate_value_string(const char * value,size_t len)566 static int drm_validate_value_string(const char *value, size_t len)
567 {
568 int i;
569
570 for (i = 0; i < len; i++) {
571 if (!isascii(value[i]) || !isgraph(value[i]))
572 return -EINVAL;
573 }
574 return 0;
575 }
576
drm_set_client_name(struct drm_device * dev,void * data,struct drm_file * file_priv)577 static int drm_set_client_name(struct drm_device *dev, void *data,
578 struct drm_file *file_priv)
579 {
580 struct drm_set_client_name *name = data;
581 size_t len = name->name_len;
582 void __user *user_ptr;
583 char *new_name;
584
585 if (len > DRM_CLIENT_NAME_MAX_LEN) {
586 return -EINVAL;
587 } else if (len) {
588 user_ptr = u64_to_user_ptr(name->name);
589
590 new_name = memdup_user_nul(user_ptr, len);
591 if (IS_ERR(new_name))
592 return PTR_ERR(new_name);
593
594 if (strlen(new_name) != len ||
595 drm_validate_value_string(new_name, len) < 0) {
596 kfree(new_name);
597 return -EINVAL;
598 }
599 } else {
600 new_name = NULL;
601 }
602
603 mutex_lock(&file_priv->client_name_lock);
604 kfree(file_priv->client_name);
605 file_priv->client_name = new_name;
606 mutex_unlock(&file_priv->client_name_lock);
607
608 return 0;
609 }
610
drm_ioctl_permit(u32 flags,struct drm_file * file_priv)611 static int drm_ioctl_permit(u32 flags, struct drm_file *file_priv)
612 {
613 /* ROOT_ONLY is only for CAP_SYS_ADMIN */
614 if (unlikely((flags & DRM_ROOT_ONLY) && !capable(CAP_SYS_ADMIN)))
615 return -EACCES;
616
617 /* AUTH is only for authenticated or render client */
618 if (unlikely((flags & DRM_AUTH) && !drm_is_render_client(file_priv) &&
619 !file_priv->authenticated))
620 return -EACCES;
621
622 /* MASTER is only for master or control clients */
623 if (unlikely((flags & DRM_MASTER) &&
624 !drm_is_current_master(file_priv)))
625 return -EACCES;
626
627 /* Render clients must be explicitly allowed */
628 if (unlikely(!(flags & DRM_RENDER_ALLOW) &&
629 drm_is_render_client(file_priv)))
630 return -EACCES;
631
632 return 0;
633 }
634
635 #define DRM_IOCTL_DEF(ioctl, _func, _flags) \
636 [DRM_IOCTL_NR(ioctl)] = { \
637 .cmd = ioctl, \
638 .func = _func, \
639 .flags = _flags, \
640 .name = #ioctl \
641 }
642
643 /* Ioctl table */
644 static const struct drm_ioctl_desc drm_ioctls[] = {
645 DRM_IOCTL_DEF(DRM_IOCTL_VERSION, drm_version, DRM_RENDER_ALLOW),
646 DRM_IOCTL_DEF(DRM_IOCTL_GET_UNIQUE, drm_getunique, 0),
647 DRM_IOCTL_DEF(DRM_IOCTL_GET_MAGIC, drm_getmagic, 0),
648
649 DRM_IOCTL_DEF(DRM_IOCTL_GET_CLIENT, drm_getclient, 0),
650 DRM_IOCTL_DEF(DRM_IOCTL_GET_STATS, drm_getstats, 0),
651 DRM_IOCTL_DEF(DRM_IOCTL_GET_CAP, drm_getcap, DRM_RENDER_ALLOW),
652 DRM_IOCTL_DEF(DRM_IOCTL_SET_CLIENT_CAP, drm_setclientcap, 0),
653 DRM_IOCTL_DEF(DRM_IOCTL_SET_VERSION, drm_setversion, DRM_MASTER),
654
655 DRM_IOCTL_DEF(DRM_IOCTL_SET_UNIQUE, drm_invalid_op, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
656 DRM_IOCTL_DEF(DRM_IOCTL_BLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
657 DRM_IOCTL_DEF(DRM_IOCTL_UNBLOCK, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
658 DRM_IOCTL_DEF(DRM_IOCTL_AUTH_MAGIC, drm_authmagic, DRM_MASTER),
659
660 DRM_IOCTL_DEF(DRM_IOCTL_SET_MASTER, drm_setmaster_ioctl, 0),
661 DRM_IOCTL_DEF(DRM_IOCTL_DROP_MASTER, drm_dropmaster_ioctl, 0),
662
663 DRM_IOCTL_DEF(DRM_IOCTL_ADD_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
664 DRM_IOCTL_DEF(DRM_IOCTL_RM_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
665
666 DRM_IOCTL_DEF(DRM_IOCTL_FINISH, drm_noop, DRM_AUTH),
667
668 DRM_IOCTL_DEF(DRM_IOCTL_WAIT_VBLANK, drm_wait_vblank_ioctl, 0),
669
670 DRM_IOCTL_DEF(DRM_IOCTL_UPDATE_DRAW, drm_noop, DRM_AUTH|DRM_MASTER|DRM_ROOT_ONLY),
671
672 DRM_IOCTL_DEF(DRM_IOCTL_GEM_CLOSE, drm_gem_close_ioctl, DRM_RENDER_ALLOW),
673 DRM_IOCTL_DEF(DRM_IOCTL_GEM_FLINK, drm_gem_flink_ioctl, DRM_AUTH),
674 DRM_IOCTL_DEF(DRM_IOCTL_GEM_OPEN, drm_gem_open_ioctl, DRM_AUTH),
675 /* see drm_gem.c:drm_gem_change_handle_ioctl for why this is invalid */
676 DRM_IOCTL_DEF(DRM_IOCTL_GEM_CHANGE_HANDLE, drm_invalid_op, DRM_RENDER_ALLOW),
677
678 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETRESOURCES, drm_mode_getresources, 0),
679
680 DRM_IOCTL_DEF(DRM_IOCTL_PRIME_HANDLE_TO_FD, drm_prime_handle_to_fd_ioctl, DRM_RENDER_ALLOW),
681 DRM_IOCTL_DEF(DRM_IOCTL_PRIME_FD_TO_HANDLE, drm_prime_fd_to_handle_ioctl, DRM_RENDER_ALLOW),
682
683 DRM_IOCTL_DEF(DRM_IOCTL_SET_CLIENT_NAME, drm_set_client_name, DRM_RENDER_ALLOW),
684
685 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPLANERESOURCES, drm_mode_getplane_res, 0),
686 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCRTC, drm_mode_getcrtc, 0),
687 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETCRTC, drm_mode_setcrtc, DRM_MASTER),
688 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPLANE, drm_mode_getplane, 0),
689 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETPLANE, drm_mode_setplane, DRM_MASTER),
690 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CURSOR, drm_mode_cursor_ioctl, DRM_MASTER),
691 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETGAMMA, drm_mode_gamma_get_ioctl, 0),
692 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETGAMMA, drm_mode_gamma_set_ioctl, DRM_MASTER),
693 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETENCODER, drm_mode_getencoder, 0),
694 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETCONNECTOR, drm_mode_getconnector, 0),
695 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ATTACHMODE, drm_noop, DRM_MASTER),
696 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DETACHMODE, drm_noop, DRM_MASTER),
697 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPERTY, drm_mode_getproperty_ioctl, 0),
698 DRM_IOCTL_DEF(DRM_IOCTL_MODE_SETPROPERTY, drm_connector_property_set_ioctl, DRM_MASTER),
699 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETPROPBLOB, drm_mode_getblob_ioctl, 0),
700 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETFB, drm_mode_getfb, 0),
701 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GETFB2, drm_mode_getfb2_ioctl, 0),
702 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB, drm_mode_addfb_ioctl, 0),
703 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ADDFB2, drm_mode_addfb2_ioctl, 0),
704 DRM_IOCTL_DEF(DRM_IOCTL_MODE_RMFB, drm_mode_rmfb_ioctl, 0),
705 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CLOSEFB, drm_mode_closefb_ioctl, 0),
706 DRM_IOCTL_DEF(DRM_IOCTL_MODE_PAGE_FLIP, drm_mode_page_flip_ioctl, DRM_MASTER),
707 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DIRTYFB, drm_mode_dirtyfb_ioctl, DRM_MASTER),
708 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATE_DUMB, drm_mode_create_dumb_ioctl, 0),
709 DRM_IOCTL_DEF(DRM_IOCTL_MODE_MAP_DUMB, drm_mode_mmap_dumb_ioctl, 0),
710 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DESTROY_DUMB, drm_mode_destroy_dumb_ioctl, 0),
711 DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_GETPROPERTIES, drm_mode_obj_get_properties_ioctl, 0),
712 DRM_IOCTL_DEF(DRM_IOCTL_MODE_OBJ_SETPROPERTY, drm_mode_obj_set_property_ioctl, DRM_MASTER),
713 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CURSOR2, drm_mode_cursor2_ioctl, DRM_MASTER),
714 DRM_IOCTL_DEF(DRM_IOCTL_MODE_ATOMIC, drm_mode_atomic_ioctl, DRM_MASTER),
715 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATEPROPBLOB, drm_mode_createblob_ioctl, 0),
716 DRM_IOCTL_DEF(DRM_IOCTL_MODE_DESTROYPROPBLOB, drm_mode_destroyblob_ioctl, 0),
717
718 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_CREATE, drm_syncobj_create_ioctl,
719 DRM_RENDER_ALLOW),
720 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_DESTROY, drm_syncobj_destroy_ioctl,
721 DRM_RENDER_ALLOW),
722 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_HANDLE_TO_FD, drm_syncobj_handle_to_fd_ioctl,
723 DRM_RENDER_ALLOW),
724 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_FD_TO_HANDLE, drm_syncobj_fd_to_handle_ioctl,
725 DRM_RENDER_ALLOW),
726 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_TRANSFER, drm_syncobj_transfer_ioctl,
727 DRM_RENDER_ALLOW),
728 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_WAIT, drm_syncobj_wait_ioctl,
729 DRM_RENDER_ALLOW),
730 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_TIMELINE_WAIT, drm_syncobj_timeline_wait_ioctl,
731 DRM_RENDER_ALLOW),
732 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_EVENTFD, drm_syncobj_eventfd_ioctl,
733 DRM_RENDER_ALLOW),
734 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_RESET, drm_syncobj_reset_ioctl,
735 DRM_RENDER_ALLOW),
736 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_SIGNAL, drm_syncobj_signal_ioctl,
737 DRM_RENDER_ALLOW),
738 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_TIMELINE_SIGNAL, drm_syncobj_timeline_signal_ioctl,
739 DRM_RENDER_ALLOW),
740 DRM_IOCTL_DEF(DRM_IOCTL_SYNCOBJ_QUERY, drm_syncobj_query_ioctl,
741 DRM_RENDER_ALLOW),
742 DRM_IOCTL_DEF(DRM_IOCTL_CRTC_GET_SEQUENCE, drm_crtc_get_sequence_ioctl, 0),
743 DRM_IOCTL_DEF(DRM_IOCTL_CRTC_QUEUE_SEQUENCE, drm_crtc_queue_sequence_ioctl, 0),
744 DRM_IOCTL_DEF(DRM_IOCTL_MODE_CREATE_LEASE, drm_mode_create_lease_ioctl, DRM_MASTER),
745 DRM_IOCTL_DEF(DRM_IOCTL_MODE_LIST_LESSEES, drm_mode_list_lessees_ioctl, DRM_MASTER),
746 DRM_IOCTL_DEF(DRM_IOCTL_MODE_GET_LEASE, drm_mode_get_lease_ioctl, DRM_MASTER),
747 DRM_IOCTL_DEF(DRM_IOCTL_MODE_REVOKE_LEASE, drm_mode_revoke_lease_ioctl, DRM_MASTER),
748 };
749
750 #define DRM_CORE_IOCTL_COUNT ARRAY_SIZE(drm_ioctls)
751
752 /**
753 * DOC: driver specific ioctls
754 *
755 * First things first, driver private IOCTLs should only be needed for drivers
756 * supporting rendering. Kernel modesetting is all standardized, and extended
757 * through properties. There are a few exceptions in some existing drivers,
758 * which define IOCTL for use by the display DRM master, but they all predate
759 * properties.
760 *
761 * Now if you do have a render driver you always have to support it through
762 * driver private properties. There's a few steps needed to wire all the things
763 * up.
764 *
765 * First you need to define the structure for your IOCTL in your driver private
766 * UAPI header in ``include/uapi/drm/my_driver_drm.h``::
767 *
768 * struct my_driver_operation {
769 * u32 some_thing;
770 * u32 another_thing;
771 * };
772 *
773 * Please make sure that you follow all the best practices from
774 * ``Documentation/process/botching-up-ioctls.rst``. Note that drm_ioctl()
775 * automatically zero-extends structures, hence make sure you can add more stuff
776 * at the end, i.e. don't put a variable sized array there.
777 *
778 * Then you need to define your IOCTL number, using one of DRM_IO(), DRM_IOR(),
779 * DRM_IOW() or DRM_IOWR(). It must start with the DRM_IOCTL\_ prefix::
780 *
781 * ##define DRM_IOCTL_MY_DRIVER_OPERATION \
782 * DRM_IOW(DRM_COMMAND_BASE, struct my_driver_operation)
783 *
784 * DRM driver private IOCTL must be in the range from DRM_COMMAND_BASE to
785 * DRM_COMMAND_END. Finally you need an array of &struct drm_ioctl_desc to wire
786 * up the handlers and set the access rights::
787 *
788 * static const struct drm_ioctl_desc my_driver_ioctls[] = {
789 * DRM_IOCTL_DEF_DRV(MY_DRIVER_OPERATION, my_driver_operation,
790 * DRM_AUTH|DRM_RENDER_ALLOW),
791 * };
792 *
793 * And then assign this to the &drm_driver.ioctls field in your driver
794 * structure.
795 *
796 * See the separate chapter on :ref:`file operations<drm_driver_fops>` for how
797 * the driver-specific IOCTLs are wired up.
798 */
799
drm_ioctl_kernel(struct file * file,drm_ioctl_t * func,void * kdata,u32 flags)800 long drm_ioctl_kernel(struct file *file, drm_ioctl_t *func, void *kdata,
801 u32 flags)
802 {
803 struct drm_file *file_priv = file->private_data;
804 struct drm_device *dev = file_priv->minor->dev;
805 int ret;
806
807 /* Update drm_file owner if fd was passed along. */
808 drm_file_update_pid(file_priv);
809
810 if (drm_dev_is_unplugged(dev))
811 return -ENODEV;
812
813 ret = drm_ioctl_permit(flags, file_priv);
814 if (unlikely(ret))
815 return ret;
816
817 return func(dev, kdata, file_priv);
818 }
819 EXPORT_SYMBOL(drm_ioctl_kernel);
820
821 /**
822 * drm_ioctl - ioctl callback implementation for DRM drivers
823 * @filp: file this ioctl is called on
824 * @cmd: ioctl cmd number
825 * @arg: user argument
826 *
827 * Looks up the ioctl function in the DRM core and the driver dispatch table,
828 * stored in &drm_driver.ioctls. It checks for necessary permission by calling
829 * drm_ioctl_permit(), and dispatches to the respective function.
830 *
831 * Returns:
832 * Zero on success, negative error code on failure.
833 */
drm_ioctl(struct file * filp,unsigned int cmd,unsigned long arg)834 long drm_ioctl(struct file *filp,
835 unsigned int cmd, unsigned long arg)
836 {
837 struct drm_file *file_priv = filp->private_data;
838 struct drm_device *dev;
839 const struct drm_ioctl_desc *ioctl = NULL;
840 drm_ioctl_t *func;
841 unsigned int nr = DRM_IOCTL_NR(cmd);
842 int retcode = -EINVAL;
843 char stack_kdata[128];
844 char *kdata = NULL;
845 unsigned int in_size, out_size, drv_size, ksize;
846 bool is_driver_ioctl;
847
848 dev = file_priv->minor->dev;
849
850 if (drm_dev_is_unplugged(dev))
851 return -ENODEV;
852
853 if (DRM_IOCTL_TYPE(cmd) != DRM_IOCTL_BASE)
854 return -ENOTTY;
855
856 is_driver_ioctl = nr >= DRM_COMMAND_BASE && nr < DRM_COMMAND_END;
857
858 if (is_driver_ioctl) {
859 /* driver ioctl */
860 unsigned int index = nr - DRM_COMMAND_BASE;
861
862 if (index >= dev->driver->num_ioctls)
863 goto err_i1;
864 index = array_index_nospec(index, dev->driver->num_ioctls);
865 ioctl = &dev->driver->ioctls[index];
866 } else {
867 /* core ioctl */
868 if (nr >= DRM_CORE_IOCTL_COUNT)
869 goto err_i1;
870 nr = array_index_nospec(nr, DRM_CORE_IOCTL_COUNT);
871 ioctl = &drm_ioctls[nr];
872 }
873
874 drv_size = _IOC_SIZE(ioctl->cmd);
875 out_size = in_size = _IOC_SIZE(cmd);
876 if ((cmd & ioctl->cmd & IOC_IN) == 0)
877 in_size = 0;
878 if ((cmd & ioctl->cmd & IOC_OUT) == 0)
879 out_size = 0;
880 ksize = max(max(in_size, out_size), drv_size);
881
882 drm_dbg_core(dev, "comm=\"%s\" pid=%d, dev=0x%lx, auth=%d, %s\n",
883 current->comm, task_pid_nr(current),
884 (long)old_encode_dev(file_priv->minor->kdev->devt),
885 file_priv->authenticated, ioctl->name);
886
887 /* Do not trust userspace, use our own definition */
888 func = ioctl->func;
889
890 if (unlikely(!func)) {
891 drm_dbg_core(dev, "no function\n");
892 retcode = -EINVAL;
893 goto err_i1;
894 }
895
896 if (ksize <= sizeof(stack_kdata)) {
897 kdata = stack_kdata;
898 } else {
899 kdata = kmalloc(ksize, GFP_KERNEL);
900 if (!kdata) {
901 retcode = -ENOMEM;
902 goto err_i1;
903 }
904 }
905
906 if (copy_from_user(kdata, (void __user *)arg, in_size) != 0) {
907 retcode = -EFAULT;
908 goto err_i1;
909 }
910
911 if (ksize > in_size)
912 memset(kdata + in_size, 0, ksize - in_size);
913
914 retcode = drm_ioctl_kernel(filp, func, kdata, ioctl->flags);
915 if (copy_to_user((void __user *)arg, kdata, out_size) != 0)
916 retcode = -EFAULT;
917
918 err_i1:
919 if (!ioctl)
920 drm_dbg_core(dev,
921 "invalid ioctl: comm=\"%s\", pid=%d, dev=0x%lx, auth=%d, cmd=0x%02x, nr=0x%02x\n",
922 current->comm, task_pid_nr(current),
923 (long)old_encode_dev(file_priv->minor->kdev->devt),
924 file_priv->authenticated, cmd, nr);
925
926 if (kdata != stack_kdata)
927 kfree(kdata);
928 if (retcode)
929 drm_dbg_core(dev, "comm=\"%s\", pid=%d, ret=%d\n",
930 current->comm, task_pid_nr(current), retcode);
931 return retcode;
932 }
933 EXPORT_SYMBOL(drm_ioctl);
934
935 /**
936 * drm_ioctl_flags - Check for core ioctl and return ioctl permission flags
937 * @nr: ioctl number
938 * @flags: where to return the ioctl permission flags
939 *
940 * This ioctl is only used by the vmwgfx driver to augment the access checks
941 * done by the drm core and insofar a pretty decent layering violation. This
942 * shouldn't be used by any drivers.
943 *
944 * Returns:
945 * True if the @nr corresponds to a DRM core ioctl number, false otherwise.
946 */
drm_ioctl_flags(unsigned int nr,unsigned int * flags)947 bool drm_ioctl_flags(unsigned int nr, unsigned int *flags)
948 {
949 if (nr >= DRM_COMMAND_BASE && nr < DRM_COMMAND_END)
950 return false;
951
952 if (nr >= DRM_CORE_IOCTL_COUNT)
953 return false;
954 nr = array_index_nospec(nr, DRM_CORE_IOCTL_COUNT);
955
956 *flags = drm_ioctls[nr].flags;
957 return true;
958 }
959 EXPORT_SYMBOL(drm_ioctl_flags);
960