1 /*
2  * Copyright (c) 2017, Mellanox Technologies inc.  All rights reserved.
3  *
4  * This software is available to you under a choice of one of two
5  * licenses.  You may choose to be licensed under the terms of the GNU
6  * General Public License (GPL) Version 2, available from the file
7  * COPYING in the main directory of this source tree, or the
8  * OpenIB.org BSD license below:
9  *
10  *     Redistribution and use in source and binary forms, with or
11  *     without modification, are permitted provided that the following
12  *     conditions are met:
13  *
14  *      - Redistributions of source code must retain the above
15  *        copyright notice, this list of conditions and the following
16  *        disclaimer.
17  *
18  *      - Redistributions in binary form must reproduce the above
19  *        copyright notice, this list of conditions and the following
20  *        disclaimer in the documentation and/or other materials
21  *        provided with the distribution.
22  *
23  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
24  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
25  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
26  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
27  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
28  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
29  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
30  * SOFTWARE.
31  */
32 
33 #include <rdma/rdma_user_ioctl.h>
34 #include <rdma/uverbs_ioctl.h>
35 #include "rdma_core.h"
36 #include "uverbs.h"
37 
38 struct bundle_alloc_head {
39 	struct bundle_alloc_head *next;
40 	u8 data[];
41 };
42 
43 struct bundle_priv {
44 	/* Must be first */
45 	struct bundle_alloc_head alloc_head;
46 	struct bundle_alloc_head *allocated_mem;
47 	size_t internal_avail;
48 	size_t internal_used;
49 
50 	struct radix_tree_root *radix;
51 	const struct uverbs_api_ioctl_method *method_elm;
52 	void __rcu **radix_slots;
53 	unsigned long radix_slots_len;
54 	u32 method_key;
55 
56 	struct ib_uverbs_attr __user *user_attrs;
57 	struct ib_uverbs_attr *uattrs;
58 
59 	DECLARE_BITMAP(uobj_finalize, UVERBS_API_ATTR_BKEY_LEN);
60 	DECLARE_BITMAP(spec_finalize, UVERBS_API_ATTR_BKEY_LEN);
61 
62 	/*
63 	 * Must be last. bundle ends in a flex array which overlaps
64 	 * internal_buffer.
65 	 */
66 	struct uverbs_attr_bundle bundle;
67 	u64 internal_buffer[32];
68 };
69 
70 /*
71  * Each method has an absolute minimum amount of memory it needs to allocate,
72  * precompute that amount and determine if the onstack memory can be used or
73  * if allocation is need.
74  */
75 void uapi_compute_bundle_size(struct uverbs_api_ioctl_method *method_elm,
76 			      unsigned int num_attrs)
77 {
78 	struct bundle_priv *pbundle;
79 	size_t bundle_size =
80 		offsetof(struct bundle_priv, internal_buffer) +
81 		sizeof(*pbundle->bundle.attrs) * method_elm->key_bitmap_len +
82 		sizeof(*pbundle->uattrs) * num_attrs;
83 
84 	method_elm->use_stack = bundle_size <= sizeof(*pbundle);
85 	method_elm->bundle_size =
86 		ALIGN(bundle_size + 256, sizeof(*pbundle->internal_buffer));
87 
88 	/* Do not want order-2 allocations for this. */
89 	WARN_ON_ONCE(method_elm->bundle_size > PAGE_SIZE);
90 }
91 
92 /**
93  * uverbs_alloc() - Quickly allocate memory for use with a bundle
94  * @bundle: The bundle
95  * @size: Number of bytes to allocate
96  * @flags: Allocator flags
97  *
98  * The bundle allocator is intended for allocations that are connected with
99  * processing the system call related to the bundle. The allocated memory is
100  * always freed once the system call completes, and cannot be freed any other
101  * way.
102  *
103  * This tries to use a small pool of pre-allocated memory for performance.
104  */
105 __malloc void *_uverbs_alloc(struct uverbs_attr_bundle *bundle, size_t size,
106 			     gfp_t flags)
107 {
108 	struct bundle_priv *pbundle =
109 		container_of(bundle, struct bundle_priv, bundle);
110 	size_t new_used;
111 	void *res;
112 
113 	if (check_add_overflow(size, pbundle->internal_used, &new_used))
114 		return ERR_PTR(-EOVERFLOW);
115 
116 	if (new_used > pbundle->internal_avail) {
117 		struct bundle_alloc_head *buf;
118 
119 		buf = kvmalloc(struct_size(buf, data, size), flags);
120 		if (!buf)
121 			return ERR_PTR(-ENOMEM);
122 		buf->next = pbundle->allocated_mem;
123 		pbundle->allocated_mem = buf;
124 		return buf->data;
125 	}
126 
127 	res = (void *)pbundle->internal_buffer + pbundle->internal_used;
128 	pbundle->internal_used =
129 		ALIGN(new_used, sizeof(*pbundle->internal_buffer));
130 	if (want_init_on_alloc(flags))
131 		memset(res, 0, size);
132 	return res;
133 }
134 EXPORT_SYMBOL(_uverbs_alloc);
135 
136 static bool uverbs_is_attr_cleared(const struct ib_uverbs_attr *uattr,
137 				   u16 len)
138 {
139 	if (uattr->len > sizeof(((struct ib_uverbs_attr *)0)->data))
140 		return ib_is_buffer_cleared(u64_to_user_ptr(uattr->data) + len,
141 					    uattr->len - len);
142 
143 	return !memchr_inv((const void *)&uattr->data + len,
144 			   0, uattr->len - len);
145 }
146 
147 static int uverbs_set_output(const struct uverbs_attr_bundle *bundle,
148 			     const struct uverbs_attr *attr)
149 {
150 	struct bundle_priv *pbundle =
151 		container_of(bundle, struct bundle_priv, bundle);
152 	u16 flags;
153 
154 	flags = pbundle->uattrs[attr->ptr_attr.uattr_idx].flags |
155 		UVERBS_ATTR_F_VALID_OUTPUT;
156 	if (put_user(flags,
157 		     &pbundle->user_attrs[attr->ptr_attr.uattr_idx].flags))
158 		return -EFAULT;
159 	return 0;
160 }
161 
162 static int uverbs_process_idrs_array(struct bundle_priv *pbundle,
163 				     const struct uverbs_api_attr *attr_uapi,
164 				     struct uverbs_objs_arr_attr *attr,
165 				     struct ib_uverbs_attr *uattr,
166 				     u32 attr_bkey)
167 {
168 	const struct uverbs_attr_spec *spec = &attr_uapi->spec;
169 	size_t array_len;
170 	u32 *idr_vals;
171 	int ret = 0;
172 	size_t i;
173 
174 	if (uattr->attr_data.reserved)
175 		return -EINVAL;
176 
177 	if (uattr->len % sizeof(u32))
178 		return -EINVAL;
179 
180 	array_len = uattr->len / sizeof(u32);
181 	if (array_len < spec->u2.objs_arr.min_len ||
182 	    array_len > spec->u2.objs_arr.max_len)
183 		return -EINVAL;
184 
185 	attr->uobjects =
186 		uverbs_alloc(&pbundle->bundle,
187 			     array_size(array_len, sizeof(*attr->uobjects)));
188 	if (IS_ERR(attr->uobjects))
189 		return PTR_ERR(attr->uobjects);
190 
191 	/*
192 	 * Since idr is 4B and *uobjects is >= 4B, we can use attr->uobjects
193 	 * to store idrs array and avoid additional memory allocation. The
194 	 * idrs array is offset to the end of the uobjects array so we will be
195 	 * able to read idr and replace with a pointer.
196 	 */
197 	idr_vals = (u32 *)(attr->uobjects + array_len) - array_len;
198 
199 	if (uattr->len > sizeof(uattr->data)) {
200 		ret = copy_from_user(idr_vals, u64_to_user_ptr(uattr->data),
201 				     uattr->len);
202 		if (ret)
203 			return -EFAULT;
204 	} else {
205 		memcpy(idr_vals, &uattr->data, uattr->len);
206 	}
207 
208 	for (i = 0; i != array_len; i++) {
209 		attr->uobjects[i] = uverbs_get_uobject_from_file(
210 			spec->u2.objs_arr.obj_type, spec->u2.objs_arr.access,
211 			idr_vals[i], &pbundle->bundle);
212 		if (IS_ERR(attr->uobjects[i])) {
213 			ret = PTR_ERR(attr->uobjects[i]);
214 			break;
215 		}
216 	}
217 
218 	attr->len = i;
219 	__set_bit(attr_bkey, pbundle->spec_finalize);
220 	return ret;
221 }
222 
223 static int uverbs_free_idrs_array(const struct uverbs_api_attr *attr_uapi,
224 				  struct uverbs_objs_arr_attr *attr,
225 				  bool commit, struct uverbs_attr_bundle *attrs)
226 {
227 	const struct uverbs_attr_spec *spec = &attr_uapi->spec;
228 	int current_ret;
229 	int ret = 0;
230 	size_t i;
231 
232 	for (i = 0; i != attr->len; i++) {
233 		current_ret = uverbs_finalize_object(attr->uobjects[i],
234 						     spec->u2.objs_arr.access,
235 						     commit, attrs);
236 		if (!ret)
237 			ret = current_ret;
238 	}
239 
240 	return ret;
241 }
242 
243 static int uverbs_process_attr(struct bundle_priv *pbundle,
244 			       const struct uverbs_api_attr *attr_uapi,
245 			       struct ib_uverbs_attr *uattr, u32 attr_bkey)
246 {
247 	const struct uverbs_attr_spec *spec = &attr_uapi->spec;
248 	struct uverbs_attr *e = &pbundle->bundle.attrs[attr_bkey];
249 	const struct uverbs_attr_spec *val_spec = spec;
250 	struct uverbs_obj_attr *o_attr;
251 
252 	switch (spec->type) {
253 	case UVERBS_ATTR_TYPE_ENUM_IN:
254 		if (uattr->attr_data.enum_data.elem_id >= spec->u.enum_def.num_elems)
255 			return -EOPNOTSUPP;
256 
257 		if (uattr->attr_data.enum_data.reserved)
258 			return -EINVAL;
259 
260 		val_spec = &spec->u2.enum_def.ids[uattr->attr_data.enum_data.elem_id];
261 
262 		/* Currently we only support PTR_IN based enums */
263 		if (val_spec->type != UVERBS_ATTR_TYPE_PTR_IN)
264 			return -EOPNOTSUPP;
265 
266 		e->ptr_attr.enum_id = uattr->attr_data.enum_data.elem_id;
267 	/* fall through */
268 	case UVERBS_ATTR_TYPE_PTR_IN:
269 		/* Ensure that any data provided by userspace beyond the known
270 		 * struct is zero. Userspace that knows how to use some future
271 		 * longer struct will fail here if used with an old kernel and
272 		 * non-zero content, making ABI compat/discovery simpler.
273 		 */
274 		if (uattr->len > val_spec->u.ptr.len &&
275 		    val_spec->zero_trailing &&
276 		    !uverbs_is_attr_cleared(uattr, val_spec->u.ptr.len))
277 			return -EOPNOTSUPP;
278 
279 	/* fall through */
280 	case UVERBS_ATTR_TYPE_PTR_OUT:
281 		if (uattr->len < val_spec->u.ptr.min_len ||
282 		    (!val_spec->zero_trailing &&
283 		     uattr->len > val_spec->u.ptr.len))
284 			return -EINVAL;
285 
286 		if (spec->type != UVERBS_ATTR_TYPE_ENUM_IN &&
287 		    uattr->attr_data.reserved)
288 			return -EINVAL;
289 
290 		e->ptr_attr.uattr_idx = uattr - pbundle->uattrs;
291 		e->ptr_attr.len = uattr->len;
292 
293 		if (val_spec->alloc_and_copy && !uverbs_attr_ptr_is_inline(e)) {
294 			void *p;
295 
296 			p = uverbs_alloc(&pbundle->bundle, uattr->len);
297 			if (IS_ERR(p))
298 				return PTR_ERR(p);
299 
300 			e->ptr_attr.ptr = p;
301 
302 			if (copy_from_user(p, u64_to_user_ptr(uattr->data),
303 					   uattr->len))
304 				return -EFAULT;
305 		} else {
306 			e->ptr_attr.data = uattr->data;
307 		}
308 		break;
309 
310 	case UVERBS_ATTR_TYPE_IDR:
311 	case UVERBS_ATTR_TYPE_FD:
312 		if (uattr->attr_data.reserved)
313 			return -EINVAL;
314 
315 		if (uattr->len != 0)
316 			return -EINVAL;
317 
318 		o_attr = &e->obj_attr;
319 		o_attr->attr_elm = attr_uapi;
320 
321 		/*
322 		 * The type of uattr->data is u64 for UVERBS_ATTR_TYPE_IDR and
323 		 * s64 for UVERBS_ATTR_TYPE_FD. We can cast the u64 to s64
324 		 * here without caring about truncation as we know that the
325 		 * IDR implementation today rejects negative IDs
326 		 */
327 		o_attr->uobject = uverbs_get_uobject_from_file(
328 			spec->u.obj.obj_type, spec->u.obj.access,
329 			uattr->data_s64, &pbundle->bundle);
330 		if (IS_ERR(o_attr->uobject))
331 			return PTR_ERR(o_attr->uobject);
332 		__set_bit(attr_bkey, pbundle->uobj_finalize);
333 
334 		if (spec->u.obj.access == UVERBS_ACCESS_NEW) {
335 			unsigned int uattr_idx = uattr - pbundle->uattrs;
336 			s64 id = o_attr->uobject->id;
337 
338 			/* Copy the allocated id to the user-space */
339 			if (put_user(id, &pbundle->user_attrs[uattr_idx].data))
340 				return -EFAULT;
341 		}
342 
343 		break;
344 
345 	case UVERBS_ATTR_TYPE_IDRS_ARRAY:
346 		return uverbs_process_idrs_array(pbundle, attr_uapi,
347 						 &e->objs_arr_attr, uattr,
348 						 attr_bkey);
349 	default:
350 		return -EOPNOTSUPP;
351 	}
352 
353 	return 0;
354 }
355 
356 /*
357  * We search the radix tree with the method prefix and now we want to fast
358  * search the suffix bits to get a particular attribute pointer. It is not
359  * totally clear to me if this breaks the radix tree encasulation or not, but
360  * it uses the iter data to determine if the method iter points at the same
361  * chunk that will store the attribute, if so it just derefs it directly. By
362  * construction in most kernel configs the method and attrs will all fit in a
363  * single radix chunk, so in most cases this will have no search. Other cases
364  * this falls back to a full search.
365  */
366 static void __rcu **uapi_get_attr_for_method(struct bundle_priv *pbundle,
367 					     u32 attr_key)
368 {
369 	void __rcu **slot;
370 
371 	if (likely(attr_key < pbundle->radix_slots_len)) {
372 		void *entry;
373 
374 		slot = pbundle->radix_slots + attr_key;
375 		entry = rcu_dereference_raw(*slot);
376 		if (likely(!radix_tree_is_internal_node(entry) && entry))
377 			return slot;
378 	}
379 
380 	return radix_tree_lookup_slot(pbundle->radix,
381 				      pbundle->method_key | attr_key);
382 }
383 
384 static int uverbs_set_attr(struct bundle_priv *pbundle,
385 			   struct ib_uverbs_attr *uattr)
386 {
387 	u32 attr_key = uapi_key_attr(uattr->attr_id);
388 	u32 attr_bkey = uapi_bkey_attr(attr_key);
389 	const struct uverbs_api_attr *attr;
390 	void __rcu **slot;
391 	int ret;
392 
393 	slot = uapi_get_attr_for_method(pbundle, attr_key);
394 	if (!slot) {
395 		/*
396 		 * Kernel does not support the attribute but user-space says it
397 		 * is mandatory
398 		 */
399 		if (uattr->flags & UVERBS_ATTR_F_MANDATORY)
400 			return -EPROTONOSUPPORT;
401 		return 0;
402 	}
403 	attr = rcu_dereference_protected(*slot, true);
404 
405 	/* Reject duplicate attributes from user-space */
406 	if (test_bit(attr_bkey, pbundle->bundle.attr_present))
407 		return -EINVAL;
408 
409 	ret = uverbs_process_attr(pbundle, attr, uattr, attr_bkey);
410 	if (ret)
411 		return ret;
412 
413 	__set_bit(attr_bkey, pbundle->bundle.attr_present);
414 
415 	return 0;
416 }
417 
418 static int ib_uverbs_run_method(struct bundle_priv *pbundle,
419 				unsigned int num_attrs)
420 {
421 	int (*handler)(struct uverbs_attr_bundle *attrs);
422 	size_t uattrs_size = array_size(sizeof(*pbundle->uattrs), num_attrs);
423 	unsigned int destroy_bkey = pbundle->method_elm->destroy_bkey;
424 	unsigned int i;
425 	int ret;
426 
427 	/* See uverbs_disassociate_api() */
428 	handler = srcu_dereference(
429 		pbundle->method_elm->handler,
430 		&pbundle->bundle.ufile->device->disassociate_srcu);
431 	if (!handler)
432 		return -EIO;
433 
434 	pbundle->uattrs = uverbs_alloc(&pbundle->bundle, uattrs_size);
435 	if (IS_ERR(pbundle->uattrs))
436 		return PTR_ERR(pbundle->uattrs);
437 	if (copy_from_user(pbundle->uattrs, pbundle->user_attrs, uattrs_size))
438 		return -EFAULT;
439 
440 	for (i = 0; i != num_attrs; i++) {
441 		ret = uverbs_set_attr(pbundle, &pbundle->uattrs[i]);
442 		if (unlikely(ret))
443 			return ret;
444 	}
445 
446 	/* User space did not provide all the mandatory attributes */
447 	if (unlikely(!bitmap_subset(pbundle->method_elm->attr_mandatory,
448 				    pbundle->bundle.attr_present,
449 				    pbundle->method_elm->key_bitmap_len)))
450 		return -EINVAL;
451 
452 	if (pbundle->method_elm->has_udata)
453 		uverbs_fill_udata(&pbundle->bundle,
454 				  &pbundle->bundle.driver_udata,
455 				  UVERBS_ATTR_UHW_IN, UVERBS_ATTR_UHW_OUT);
456 	else
457 		pbundle->bundle.driver_udata = (struct ib_udata){};
458 
459 	if (destroy_bkey != UVERBS_API_ATTR_BKEY_LEN) {
460 		struct uverbs_obj_attr *destroy_attr =
461 			&pbundle->bundle.attrs[destroy_bkey].obj_attr;
462 
463 		ret = uobj_destroy(destroy_attr->uobject, &pbundle->bundle);
464 		if (ret)
465 			return ret;
466 		__clear_bit(destroy_bkey, pbundle->uobj_finalize);
467 
468 		ret = handler(&pbundle->bundle);
469 		uobj_put_destroy(destroy_attr->uobject);
470 	} else {
471 		ret = handler(&pbundle->bundle);
472 	}
473 
474 	/*
475 	 * Until the drivers are revised to use the bundle directly we have to
476 	 * assume that the driver wrote to its UHW_OUT and flag userspace
477 	 * appropriately.
478 	 */
479 	if (!ret && pbundle->method_elm->has_udata) {
480 		const struct uverbs_attr *attr =
481 			uverbs_attr_get(&pbundle->bundle, UVERBS_ATTR_UHW_OUT);
482 
483 		if (!IS_ERR(attr))
484 			ret = uverbs_set_output(&pbundle->bundle, attr);
485 	}
486 
487 	/*
488 	 * EPROTONOSUPPORT is ONLY to be returned if the ioctl framework can
489 	 * not invoke the method because the request is not supported.  No
490 	 * other cases should return this code.
491 	 */
492 	if (WARN_ON_ONCE(ret == -EPROTONOSUPPORT))
493 		return -EINVAL;
494 
495 	return ret;
496 }
497 
498 static int bundle_destroy(struct bundle_priv *pbundle, bool commit)
499 {
500 	unsigned int key_bitmap_len = pbundle->method_elm->key_bitmap_len;
501 	struct bundle_alloc_head *memblock;
502 	unsigned int i;
503 	int ret = 0;
504 
505 	/* fast path for simple uobjects */
506 	i = -1;
507 	while ((i = find_next_bit(pbundle->uobj_finalize, key_bitmap_len,
508 				  i + 1)) < key_bitmap_len) {
509 		struct uverbs_attr *attr = &pbundle->bundle.attrs[i];
510 		int current_ret;
511 
512 		current_ret = uverbs_finalize_object(
513 			attr->obj_attr.uobject,
514 			attr->obj_attr.attr_elm->spec.u.obj.access, commit,
515 			&pbundle->bundle);
516 		if (!ret)
517 			ret = current_ret;
518 	}
519 
520 	i = -1;
521 	while ((i = find_next_bit(pbundle->spec_finalize, key_bitmap_len,
522 				  i + 1)) < key_bitmap_len) {
523 		struct uverbs_attr *attr = &pbundle->bundle.attrs[i];
524 		const struct uverbs_api_attr *attr_uapi;
525 		void __rcu **slot;
526 		int current_ret;
527 
528 		slot = uapi_get_attr_for_method(
529 			pbundle,
530 			pbundle->method_key | uapi_bkey_to_key_attr(i));
531 		if (WARN_ON(!slot))
532 			continue;
533 
534 		attr_uapi = rcu_dereference_protected(*slot, true);
535 
536 		if (attr_uapi->spec.type == UVERBS_ATTR_TYPE_IDRS_ARRAY) {
537 			current_ret = uverbs_free_idrs_array(
538 				attr_uapi, &attr->objs_arr_attr, commit,
539 				&pbundle->bundle);
540 			if (!ret)
541 				ret = current_ret;
542 		}
543 	}
544 
545 	for (memblock = pbundle->allocated_mem; memblock;) {
546 		struct bundle_alloc_head *tmp = memblock;
547 
548 		memblock = memblock->next;
549 		kvfree(tmp);
550 	}
551 
552 	return ret;
553 }
554 
555 static int ib_uverbs_cmd_verbs(struct ib_uverbs_file *ufile,
556 			       struct ib_uverbs_ioctl_hdr *hdr,
557 			       struct ib_uverbs_attr __user *user_attrs)
558 {
559 	const struct uverbs_api_ioctl_method *method_elm;
560 	struct uverbs_api *uapi = ufile->device->uapi;
561 	struct radix_tree_iter attrs_iter;
562 	struct bundle_priv *pbundle;
563 	struct bundle_priv onstack;
564 	void __rcu **slot;
565 	int destroy_ret;
566 	int ret;
567 
568 	if (unlikely(hdr->driver_id != uapi->driver_id))
569 		return -EINVAL;
570 
571 	slot = radix_tree_iter_lookup(
572 		&uapi->radix, &attrs_iter,
573 		uapi_key_obj(hdr->object_id) |
574 			uapi_key_ioctl_method(hdr->method_id));
575 	if (unlikely(!slot))
576 		return -EPROTONOSUPPORT;
577 	method_elm = rcu_dereference_protected(*slot, true);
578 
579 	if (!method_elm->use_stack) {
580 		pbundle = kmalloc(method_elm->bundle_size, GFP_KERNEL);
581 		if (!pbundle)
582 			return -ENOMEM;
583 		pbundle->internal_avail =
584 			method_elm->bundle_size -
585 			offsetof(struct bundle_priv, internal_buffer);
586 		pbundle->alloc_head.next = NULL;
587 		pbundle->allocated_mem = &pbundle->alloc_head;
588 	} else {
589 		pbundle = &onstack;
590 		pbundle->internal_avail = sizeof(pbundle->internal_buffer);
591 		pbundle->allocated_mem = NULL;
592 	}
593 
594 	/* Space for the pbundle->bundle.attrs flex array */
595 	pbundle->method_elm = method_elm;
596 	pbundle->method_key = attrs_iter.index;
597 	pbundle->bundle.ufile = ufile;
598 	pbundle->bundle.context = NULL; /* only valid if bundle has uobject */
599 	pbundle->radix = &uapi->radix;
600 	pbundle->radix_slots = slot;
601 	pbundle->radix_slots_len = radix_tree_chunk_size(&attrs_iter);
602 	pbundle->user_attrs = user_attrs;
603 
604 	pbundle->internal_used = ALIGN(pbundle->method_elm->key_bitmap_len *
605 					       sizeof(*pbundle->bundle.attrs),
606 				       sizeof(*pbundle->internal_buffer));
607 	memset(pbundle->bundle.attr_present, 0,
608 	       sizeof(pbundle->bundle.attr_present));
609 	memset(pbundle->uobj_finalize, 0, sizeof(pbundle->uobj_finalize));
610 	memset(pbundle->spec_finalize, 0, sizeof(pbundle->spec_finalize));
611 
612 	ret = ib_uverbs_run_method(pbundle, hdr->num_attrs);
613 	destroy_ret = bundle_destroy(pbundle, ret == 0);
614 	if (unlikely(destroy_ret && !ret))
615 		return destroy_ret;
616 
617 	return ret;
618 }
619 
620 long ib_uverbs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
621 {
622 	struct ib_uverbs_file *file = filp->private_data;
623 	struct ib_uverbs_ioctl_hdr __user *user_hdr =
624 		(struct ib_uverbs_ioctl_hdr __user *)arg;
625 	struct ib_uverbs_ioctl_hdr hdr;
626 	int srcu_key;
627 	int err;
628 
629 	if (unlikely(cmd != RDMA_VERBS_IOCTL))
630 		return -ENOIOCTLCMD;
631 
632 	err = copy_from_user(&hdr, user_hdr, sizeof(hdr));
633 	if (err)
634 		return -EFAULT;
635 
636 	if (hdr.length > PAGE_SIZE ||
637 	    hdr.length != struct_size(&hdr, attrs, hdr.num_attrs))
638 		return -EINVAL;
639 
640 	if (hdr.reserved1 || hdr.reserved2)
641 		return -EPROTONOSUPPORT;
642 
643 	srcu_key = srcu_read_lock(&file->device->disassociate_srcu);
644 	err = ib_uverbs_cmd_verbs(file, &hdr, user_hdr->attrs);
645 	srcu_read_unlock(&file->device->disassociate_srcu, srcu_key);
646 	return err;
647 }
648 
649 int uverbs_get_flags64(u64 *to, const struct uverbs_attr_bundle *attrs_bundle,
650 		       size_t idx, u64 allowed_bits)
651 {
652 	const struct uverbs_attr *attr;
653 	u64 flags;
654 
655 	attr = uverbs_attr_get(attrs_bundle, idx);
656 	/* Missing attribute means 0 flags */
657 	if (IS_ERR(attr)) {
658 		*to = 0;
659 		return 0;
660 	}
661 
662 	/*
663 	 * New userspace code should use 8 bytes to pass flags, but we
664 	 * transparently support old userspaces that were using 4 bytes as
665 	 * well.
666 	 */
667 	if (attr->ptr_attr.len == 8)
668 		flags = attr->ptr_attr.data;
669 	else if (attr->ptr_attr.len == 4)
670 		flags = *(u32 *)&attr->ptr_attr.data;
671 	else
672 		return -EINVAL;
673 
674 	if (flags & ~allowed_bits)
675 		return -EINVAL;
676 
677 	*to = flags;
678 	return 0;
679 }
680 EXPORT_SYMBOL(uverbs_get_flags64);
681 
682 int uverbs_get_flags32(u32 *to, const struct uverbs_attr_bundle *attrs_bundle,
683 		       size_t idx, u64 allowed_bits)
684 {
685 	u64 flags;
686 	int ret;
687 
688 	ret = uverbs_get_flags64(&flags, attrs_bundle, idx, allowed_bits);
689 	if (ret)
690 		return ret;
691 
692 	if (flags > U32_MAX)
693 		return -EINVAL;
694 	*to = flags;
695 
696 	return 0;
697 }
698 EXPORT_SYMBOL(uverbs_get_flags32);
699 
700 /*
701  * Fill a ib_udata struct (core or uhw) using the given attribute IDs.
702  * This is primarily used to convert the UVERBS_ATTR_UHW() into the
703  * ib_udata format used by the drivers.
704  */
705 void uverbs_fill_udata(struct uverbs_attr_bundle *bundle,
706 		       struct ib_udata *udata, unsigned int attr_in,
707 		       unsigned int attr_out)
708 {
709 	struct bundle_priv *pbundle =
710 		container_of(bundle, struct bundle_priv, bundle);
711 	const struct uverbs_attr *in =
712 		uverbs_attr_get(&pbundle->bundle, attr_in);
713 	const struct uverbs_attr *out =
714 		uverbs_attr_get(&pbundle->bundle, attr_out);
715 
716 	if (!IS_ERR(in)) {
717 		udata->inlen = in->ptr_attr.len;
718 		if (uverbs_attr_ptr_is_inline(in))
719 			udata->inbuf =
720 				&pbundle->user_attrs[in->ptr_attr.uattr_idx]
721 					 .data;
722 		else
723 			udata->inbuf = u64_to_user_ptr(in->ptr_attr.data);
724 	} else {
725 		udata->inbuf = NULL;
726 		udata->inlen = 0;
727 	}
728 
729 	if (!IS_ERR(out)) {
730 		udata->outbuf = u64_to_user_ptr(out->ptr_attr.data);
731 		udata->outlen = out->ptr_attr.len;
732 	} else {
733 		udata->outbuf = NULL;
734 		udata->outlen = 0;
735 	}
736 }
737 
738 int uverbs_copy_to(const struct uverbs_attr_bundle *bundle, size_t idx,
739 		   const void *from, size_t size)
740 {
741 	const struct uverbs_attr *attr = uverbs_attr_get(bundle, idx);
742 	size_t min_size;
743 
744 	if (IS_ERR(attr))
745 		return PTR_ERR(attr);
746 
747 	min_size = min_t(size_t, attr->ptr_attr.len, size);
748 	if (copy_to_user(u64_to_user_ptr(attr->ptr_attr.data), from, min_size))
749 		return -EFAULT;
750 
751 	return uverbs_set_output(bundle, attr);
752 }
753 EXPORT_SYMBOL(uverbs_copy_to);
754 
755 
756 /*
757  * This is only used if the caller has directly used copy_to_use to write the
758  * data.  It signals to user space that the buffer is filled in.
759  */
760 int uverbs_output_written(const struct uverbs_attr_bundle *bundle, size_t idx)
761 {
762 	const struct uverbs_attr *attr = uverbs_attr_get(bundle, idx);
763 
764 	if (IS_ERR(attr))
765 		return PTR_ERR(attr);
766 
767 	return uverbs_set_output(bundle, attr);
768 }
769 
770 int _uverbs_get_const(s64 *to, const struct uverbs_attr_bundle *attrs_bundle,
771 		      size_t idx, s64 lower_bound, u64 upper_bound,
772 		      s64  *def_val)
773 {
774 	const struct uverbs_attr *attr;
775 
776 	attr = uverbs_attr_get(attrs_bundle, idx);
777 	if (IS_ERR(attr)) {
778 		if ((PTR_ERR(attr) != -ENOENT) || !def_val)
779 			return PTR_ERR(attr);
780 
781 		*to = *def_val;
782 	} else {
783 		*to = attr->ptr_attr.data;
784 	}
785 
786 	if (*to < lower_bound || (*to > 0 && (u64)*to > upper_bound))
787 		return -EINVAL;
788 
789 	return 0;
790 }
791 EXPORT_SYMBOL(_uverbs_get_const);
792 
793 int uverbs_copy_to_struct_or_zero(const struct uverbs_attr_bundle *bundle,
794 				  size_t idx, const void *from, size_t size)
795 {
796 	const struct uverbs_attr *attr = uverbs_attr_get(bundle, idx);
797 
798 	if (IS_ERR(attr))
799 		return PTR_ERR(attr);
800 
801 	if (size < attr->ptr_attr.len) {
802 		if (clear_user(u64_to_user_ptr(attr->ptr_attr.data) + size,
803 			       attr->ptr_attr.len - size))
804 			return -EFAULT;
805 	}
806 	return uverbs_copy_to(bundle, idx, from, size);
807 }
808