aboutsummaryrefslogtreecommitdiffstats
path: root/drivers/infiniband/core/uverbs_ioctl.c
blob: db7a92ea5dbe8783c2c036ddad49bfa20424b970 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
/*
 * Copyright (c) 2017, Mellanox Technologies inc.  All rights reserved.
 *
 * This software is available to you under a choice of one of two
 * licenses.  You may choose to be licensed under the terms of the GNU
 * General Public License (GPL) Version 2, available from the file
 * COPYING in the main directory of this source tree, or the
 * OpenIB.org BSD license below:
 *
 *     Redistribution and use in source and binary forms, with or
 *     without modification, are permitted provided that the following
 *     conditions are met:
 *
 *      - Redistributions of source code must retain the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer.
 *
 *      - Redistributions in binary form must reproduce the above
 *        copyright notice, this list of conditions and the following
 *        disclaimer in the documentation and/or other materials
 *        provided with the distribution.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
 * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
 * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
 * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 */

#include <rdma/rdma_user_ioctl.h>
#include <rdma/uverbs_ioctl.h>
#include "rdma_core.h"
#include "uverbs.h"

static bool uverbs_is_attr_cleared(const struct ib_uverbs_attr *uattr,
				   u16 len)
{
	if (uattr->len > sizeof(((struct ib_uverbs_attr *)0)->data))
		return ib_is_buffer_cleared(u64_to_user_ptr(uattr->data) + len,
					    uattr->len - len);

	return !memchr_inv((const void *)&uattr->data + len,
			   0, uattr->len - len);
}

static int uverbs_process_attr(struct ib_uverbs_file *ufile,
			       const struct ib_uverbs_attr *uattr,
			       u16 attr_id,
			       const struct uverbs_attr_spec_hash *attr_spec_bucket,
			       struct uverbs_attr_bundle_hash *attr_bundle_h,
			       struct ib_uverbs_attr __user *uattr_ptr)
{
	const struct uverbs_attr_spec *spec;
	const struct uverbs_attr_spec *val_spec;
	struct uverbs_attr *e;
	const struct uverbs_object_spec *object;
	struct uverbs_obj_attr *o_attr;
	struct uverbs_attr *elements = attr_bundle_h->attrs;

	if (attr_id >= attr_spec_bucket->num_attrs) {
		if (uattr->flags & UVERBS_ATTR_F_MANDATORY)
			return -EINVAL;
		else
			return 0;
	}

	if (test_bit(attr_id, attr_bundle_h->valid_bitmap))
		return -EINVAL;

	spec = &attr_spec_bucket->attrs[attr_id];
	val_spec = spec;
	e = &elements[attr_id];
	e->uattr = uattr_ptr;

	switch (spec->type) {
	case UVERBS_ATTR_TYPE_ENUM_IN:
		if (uattr->attr_data.enum_data.elem_id >= spec->u.enum_def.num_elems)
			return -EOPNOTSUPP;

		if (uattr->attr_data.enum_data.reserved)
			return -EINVAL;

		val_spec = &spec->u2.enum_def.ids[uattr->attr_data.enum_data.elem_id];

		/* Currently we only support PTR_IN based enums */
		if (val_spec->type != UVERBS_ATTR_TYPE_PTR_IN)
			return -EOPNOTSUPP;

		e->ptr_attr.enum_id = uattr->attr_data.enum_data.elem_id;
	/* fall through */
	case UVERBS_ATTR_TYPE_PTR_IN:
		/* Ensure that any data provided by userspace beyond the known
		 * struct is zero. Userspace that knows how to use some future
		 * longer struct will fail here if used with an old kernel and
		 * non-zero content, making ABI compat/discovery simpler.
		 */
		if (uattr->len > val_spec->u.ptr.len &&
		    val_spec->zero_trailing &&
		    !uverbs_is_attr_cleared(uattr, val_spec->u.ptr.len))
			return -EOPNOTSUPP;

	/* fall through */
	case UVERBS_ATTR_TYPE_PTR_OUT:
		if (uattr->len < val_spec->u.ptr.min_len ||
		    (!val_spec->zero_trailing &&
		     uattr->len > val_spec->u.ptr.len))
			return -EINVAL;

		if (spec->type != UVERBS_ATTR_TYPE_ENUM_IN &&
		    uattr->attr_data.reserved)
			return -EINVAL;

		e->ptr_attr.len = uattr->len;
		e->ptr_attr.flags = uattr->flags;

		if (val_spec->alloc_and_copy && !uverbs_attr_ptr_is_inline(e)) {
			void *p;

			p = kvmalloc(uattr->len, GFP_KERNEL);
			if (!p)
				return -ENOMEM;

			e->ptr_attr.ptr = p;

			if (copy_from_user(p, u64_to_user_ptr(uattr->data),
					   uattr->len)) {
				kvfree(p);
				return -EFAULT;
			}
		} else {
			e->ptr_attr.data = uattr->data;
		}
		break;

	case UVERBS_ATTR_TYPE_IDR:
	case UVERBS_ATTR_TYPE_FD:
		if (uattr->attr_data.reserved)
			return -EINVAL;

		if (uattr->len != 0)
			return -EINVAL;

		o_attr = &e->obj_attr;
		object = uverbs_get_object(ufile, spec->u.obj.obj_type);
		if (!object)
			return -EINVAL;

		/*
		 * The type of uattr->data is u64 for UVERBS_ATTR_TYPE_IDR and
		 * s64 for UVERBS_ATTR_TYPE_FD. We can cast the u64 to s64
		 * here without caring about truncation as we know that the
		 * IDR implementation today rejects negative IDs
		 */
		o_attr->uobject = uverbs_get_uobject_from_file(
					object->type_attrs,
					ufile,
					spec->u.obj.access,
					uattr->data_s64);

		if (IS_ERR(o_attr->uobject))
			return PTR_ERR(o_attr->uobject);

		if (spec->u.obj.access == UVERBS_ACCESS_NEW) {
			s64 id = o_attr->uobject->id;

			/* Copy the allocated id to the user-space */
			if (put_user(id, &e->uattr->data)) {
				uverbs_finalize_object(o_attr->uobject,
						       UVERBS_ACCESS_NEW,
						       false);
				return -EFAULT;
			}
		}

		break;
	default:
		return -EOPNOTSUPP;
	}

	set_bit(attr_id, attr_bundle_h->valid_bitmap);
	return 0;
}

static int uverbs_finalize_attrs(struct uverbs_attr_bundle *attrs_bundle,
				 struct uverbs_attr_spec_hash *const *spec_hash,
				 size_t num, bool commit)
{
	unsigned int i;
	int ret = 0;

	for (i = 0; i < num; i++) {
		struct uverbs_attr_bundle_hash *curr_bundle =
			&attrs_bundle->hash[i];
		const struct uverbs_attr_spec_hash *curr_spec_bucket =
			spec_hash[i];
		unsigned int j;

		if (!curr_spec_bucket)
			continue;

		for (j = 0; j < curr_bundle->num_attrs; j++) {
			struct uverbs_attr *attr;
			const struct uverbs_attr_spec *spec;

			if (!uverbs_attr_is_valid_in_hash(curr_bundle, j))
				continue;

			attr = &curr_bundle->attrs[j];
			spec = &curr_spec_bucket->attrs[j];

			if (spec->type == UVERBS_ATTR_TYPE_IDR ||
			    spec->type == UVERBS_ATTR_TYPE_FD) {
				int current_ret;

				current_ret = uverbs_finalize_object(
					attr->obj_attr.uobject,
					spec->u.obj.access, commit);
				if (!ret)
					ret = current_ret;
			} else if (spec->type == UVERBS_ATTR_TYPE_PTR_IN &&
				   spec->alloc_and_copy &&
				   !uverbs_attr_ptr_is_inline(attr)) {
				kvfree(attr->ptr_attr.ptr);
			}
		}
	}
	return ret;
}

static int uverbs_uattrs_process(struct ib_uverbs_file *ufile,
				 const struct ib_uverbs_attr *uattrs,
				 size_t num_uattrs,
				 const struct uverbs_method_spec *method,
				 struct uverbs_attr_bundle *attr_bundle,
				 struct ib_uverbs_attr __user *uattr_ptr)
{
	size_t i;
	int ret = 0;
	int num_given_buckets = 0;

	for (i = 0; i < num_uattrs; i++) {
		const struct ib_uverbs_attr *uattr = &uattrs[i];
		u16 attr_id = uattr->attr_id;
		struct uverbs_attr_spec_hash *attr_spec_bucket;

		ret = uverbs_ns_idx(&attr_id, method->num_buckets);
		if (ret < 0 || !method->attr_buckets[ret]) {
			if (uattr->flags & UVERBS_ATTR_F_MANDATORY) {
				uverbs_finalize_attrs(attr_bundle,
						      method->attr_buckets,
						      num_given_buckets,
						      false);
				return ret;
			}
			continue;
		}

		/*
		 * ret is the found ns, so increase num_given_buckets if
		 * necessary.
		 */
		if (ret >= num_given_buckets)
			num_given_buckets = ret + 1;

		attr_spec_bucket = method->attr_buckets[ret];
		ret = uverbs_process_attr(ufile, uattr, attr_id,
					  attr_spec_bucket,
					  &attr_bundle->hash[ret], uattr_ptr++);
		if (ret) {
			uverbs_finalize_attrs(attr_bundle,
					      method->attr_buckets,
					      num_given_buckets,
					      false);
			return ret;
		}
	}

	return num_given_buckets;
}

static int uverbs_validate_kernel_mandatory(const struct uverbs_method_spec *method_spec,
					    struct uverbs_attr_bundle *attr_bundle)
{
	unsigned int i;

	for (i = 0; i < attr_bundle->num_buckets; i++) {
		struct uverbs_attr_spec_hash *attr_spec_bucket =
			method_spec->attr_buckets[i];

		if (!attr_spec_bucket)
			continue;

		if (!bitmap_subset(attr_spec_bucket->mandatory_attrs_bitmask,
				   attr_bundle->hash[i].valid_bitmap,
				   attr_spec_bucket->num_attrs))
			return -EINVAL;
	}

	for (; i < method_spec->num_buckets; i++) {
		struct uverbs_attr_spec_hash *attr_spec_bucket =
			method_spec->attr_buckets[i];

		if (!bitmap_empty(attr_spec_bucket->mandatory_attrs_bitmask,
				  attr_spec_bucket->num_attrs))
			return -EINVAL;
	}

	return 0;
}

static int uverbs_handle_method(struct ib_uverbs_attr __user *uattr_ptr,
				const struct ib_uverbs_attr *uattrs,
				size_t num_uattrs,
				struct ib_device *ibdev,
				struct ib_uverbs_file *ufile,
				const struct uverbs_method_spec *method_spec,
				struct uverbs_attr_bundle *attr_bundle)
{
	int ret;
	int finalize_ret;
	int num_given_buckets;

	num_given_buckets = uverbs_uattrs_process(
		ufile, uattrs, num_uattrs, method_spec, attr_bundle, uattr_ptr);
	if (num_given_buckets <= 0)
		return -EINVAL;

	attr_bundle->num_buckets = num_given_buckets;
	ret = uverbs_validate_kernel_mandatory(method_spec, attr_bundle);
	if (ret)
		goto cleanup;

	ret = method_spec->handler(ibdev, ufile, attr_bundle);
cleanup:
	finalize_ret = uverbs_finalize_attrs(attr_bundle,
					     method_spec->attr_buckets,
					     attr_bundle->num_buckets,
					     !ret);

	return ret ? ret : finalize_ret;
}

#define UVERBS_OPTIMIZE_USING_STACK_SZ  256
static long ib_uverbs_cmd_verbs(struct ib_device *ib_dev,
				struct ib_uverbs_file *file,
				struct ib_uverbs_ioctl_hdr *hdr,
				void __user *buf)
{
	const struct uverbs_object_spec *object_spec;
	const struct uverbs_method_spec *method_spec;
	long err = 0;
	unsigned int i;
	struct {
		struct ib_uverbs_attr		*uattrs;
		struct uverbs_attr_bundle	*uverbs_attr_bundle;
	} *ctx = NULL;
	struct uverbs_attr *curr_attr;
	unsigned long *curr_bitmap;
	size_t ctx_size;
	uintptr_t data[UVERBS_OPTIMIZE_USING_STACK_SZ / sizeof(uintptr_t)];

	if (hdr->driver_id != ib_dev->driver_id)
		return -EINVAL;

	object_spec = uverbs_get_object(file, hdr->object_id);
	if (!object_spec)
		return -EPROTONOSUPPORT;

	method_spec = uverbs_get_method(object_spec, hdr->method_id);
	if (!method_spec)
		return -EPROTONOSUPPORT;

	ctx_size = sizeof(*ctx) +
		   sizeof(struct uverbs_attr_bundle) +
		   sizeof(struct uverbs_attr_bundle_hash) * method_spec->num_buckets +
		   sizeof(*ctx->uattrs) * hdr->num_attrs +
		   sizeof(*ctx->uverbs_attr_bundle->hash[0].attrs) *
		   method_spec->num_child_attrs +
		   sizeof(*ctx->uverbs_attr_bundle->hash[0].valid_bitmap) *
			(method_spec->num_child_attrs / BITS_PER_LONG +
			 method_spec->num_buckets);

	if (ctx_size <= UVERBS_OPTIMIZE_USING_STACK_SZ)
		ctx = (void *)data;
	if (!ctx)
		ctx = kmalloc(ctx_size, GFP_KERNEL);
	if (!ctx)
		return -ENOMEM;

	ctx->uverbs_attr_bundle = (void *)ctx + sizeof(*ctx);
	ctx->uattrs = (void *)(ctx->uverbs_attr_bundle + 1) +
			      (sizeof(ctx->uverbs_attr_bundle->hash[0]) *
			       method_spec->num_buckets);
	curr_attr = (void *)(ctx->uattrs + hdr->num_attrs);
	curr_bitmap = (void *)(curr_attr + method_spec->num_child_attrs);

	/*
	 * We just fill the pointers and num_attrs here. The data itself will be
	 * filled at a later stage (uverbs_process_attr)
	 */
	for (i = 0; i < method_spec->num_buckets; i++) {
		unsigned int curr_num_attrs;

		if (!method_spec->attr_buckets[i])
			continue;

		curr_num_attrs = method_spec->attr_buckets[i]->num_attrs;

		ctx->uverbs_attr_bundle->hash[i].attrs = curr_attr;
		curr_attr += curr_num_attrs;
		ctx->uverbs_attr_bundle->hash[i].num_attrs = curr_num_attrs;
		ctx->uverbs_attr_bundle->hash[i].valid_bitmap = curr_bitmap;
		bitmap_zero(curr_bitmap, curr_num_attrs);
		curr_bitmap += BITS_TO_LONGS(curr_num_attrs);
	}

	err = copy_from_user(ctx->uattrs, buf,
			     sizeof(*ctx->uattrs) * hdr->num_attrs);
	if (err) {
		err = -EFAULT;
		goto out;
	}

	err = uverbs_handle_method(buf, ctx->uattrs, hdr->num_attrs, ib_dev,
				   file, method_spec, ctx->uverbs_attr_bundle);

	/*
	 * EPROTONOSUPPORT is ONLY to be returned if the ioctl framework can
	 * not invoke the method because the request is not supported.  No
	 * other cases should return this code.
	*/
	if (unlikely(err == -EPROTONOSUPPORT)) {
		WARN_ON_ONCE(err == -EPROTONOSUPPORT);
		err = -EINVAL;
	}
out:
	if (ctx != (void *)data)
		kfree(ctx);
	return err;
}

#define IB_UVERBS_MAX_CMD_SZ 4096

long ib_uverbs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
	struct ib_uverbs_file *file = filp->private_data;
	struct ib_uverbs_ioctl_hdr __user *user_hdr =
		(struct ib_uverbs_ioctl_hdr __user *)arg;
	struct ib_uverbs_ioctl_hdr hdr;
	struct ib_device *ib_dev;
	int srcu_key;
	long err;

	srcu_key = srcu_read_lock(&file->device->disassociate_srcu);
	ib_dev = srcu_dereference(file->device->ib_dev,
				  &file->device->disassociate_srcu);
	if (!ib_dev) {
		err = -EIO;
		goto out;
	}

	if (cmd == RDMA_VERBS_IOCTL) {
		err = copy_from_user(&hdr, user_hdr, sizeof(hdr));

		if (err || hdr.length > IB_UVERBS_MAX_CMD_SZ ||
		    hdr.length != sizeof(hdr) + hdr.num_attrs * sizeof(struct ib_uverbs_attr)) {
			err = -EINVAL;
			goto out;
		}

		if (hdr.reserved1 || hdr.reserved2) {
			err = -EPROTONOSUPPORT;
			goto out;
		}

		err = ib_uverbs_cmd_verbs(ib_dev, file, &hdr,
					  (__user void *)arg + sizeof(hdr));
	} else {
		err = -ENOIOCTLCMD;
	}
out:
	srcu_read_unlock(&file->device->disassociate_srcu, srcu_key);

	return err;
}