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1 // SPDX-License-Identifier: GPL-2.0-only
2 /* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
3  */
4 #include <linux/bpf.h>
5 #include <linux/bpf_trace.h>
6 #include <linux/bpf_lirc.h>
7 #include <linux/btf.h>
8 #include <linux/syscalls.h>
9 #include <linux/slab.h>
10 #include <linux/sched/signal.h>
11 #include <linux/vmalloc.h>
12 #include <linux/mmzone.h>
13 #include <linux/anon_inodes.h>
14 #include <linux/fdtable.h>
15 #include <linux/file.h>
16 #include <linux/fs.h>
17 #include <linux/license.h>
18 #include <linux/filter.h>
19 #include <linux/version.h>
20 #include <linux/kernel.h>
21 #include <linux/idr.h>
22 #include <linux/cred.h>
23 #include <linux/timekeeping.h>
24 #include <linux/ctype.h>
25 #include <linux/nospec.h>
26 
27 #define IS_FD_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PROG_ARRAY || \
28 			   (map)->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || \
29 			   (map)->map_type == BPF_MAP_TYPE_CGROUP_ARRAY || \
30 			   (map)->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS)
31 #define IS_FD_HASH(map) ((map)->map_type == BPF_MAP_TYPE_HASH_OF_MAPS)
32 #define IS_FD_MAP(map) (IS_FD_ARRAY(map) || IS_FD_HASH(map))
33 
34 #define BPF_OBJ_FLAG_MASK   (BPF_F_RDONLY | BPF_F_WRONLY)
35 
36 DEFINE_PER_CPU(int, bpf_prog_active);
37 static DEFINE_IDR(prog_idr);
38 static DEFINE_SPINLOCK(prog_idr_lock);
39 static DEFINE_IDR(map_idr);
40 static DEFINE_SPINLOCK(map_idr_lock);
41 
42 int sysctl_unprivileged_bpf_disabled __read_mostly =
43 	IS_BUILTIN(CONFIG_BPF_UNPRIV_DEFAULT_OFF) ? 2 : 0;
44 
45 static const struct bpf_map_ops * const bpf_map_types[] = {
46 #define BPF_PROG_TYPE(_id, _ops)
47 #define BPF_MAP_TYPE(_id, _ops) \
48 	[_id] = &_ops,
49 #include <linux/bpf_types.h>
50 #undef BPF_PROG_TYPE
51 #undef BPF_MAP_TYPE
52 };
53 
54 /*
55  * If we're handed a bigger struct than we know of, ensure all the unknown bits
56  * are 0 - i.e. new user-space does not rely on any kernel feature extensions
57  * we don't know about yet.
58  *
59  * There is a ToCToU between this function call and the following
60  * copy_from_user() call. However, this is not a concern since this function is
61  * meant to be a future-proofing of bits.
62  */
bpf_check_uarg_tail_zero(void __user * uaddr,size_t expected_size,size_t actual_size)63 int bpf_check_uarg_tail_zero(void __user *uaddr,
64 			     size_t expected_size,
65 			     size_t actual_size)
66 {
67 	unsigned char __user *addr;
68 	unsigned char __user *end;
69 	unsigned char val;
70 	int err;
71 
72 	if (unlikely(actual_size > PAGE_SIZE))	/* silly large */
73 		return -E2BIG;
74 
75 	if (unlikely(!access_ok(uaddr, actual_size)))
76 		return -EFAULT;
77 
78 	if (actual_size <= expected_size)
79 		return 0;
80 
81 	addr = uaddr + expected_size;
82 	end  = uaddr + actual_size;
83 
84 	for (; addr < end; addr++) {
85 		err = get_user(val, addr);
86 		if (err)
87 			return err;
88 		if (val)
89 			return -E2BIG;
90 	}
91 
92 	return 0;
93 }
94 
95 const struct bpf_map_ops bpf_map_offload_ops = {
96 	.map_alloc = bpf_map_offload_map_alloc,
97 	.map_free = bpf_map_offload_map_free,
98 	.map_check_btf = map_check_no_btf,
99 };
100 
find_and_alloc_map(union bpf_attr * attr)101 static struct bpf_map *find_and_alloc_map(union bpf_attr *attr)
102 {
103 	const struct bpf_map_ops *ops;
104 	u32 type = attr->map_type;
105 	struct bpf_map *map;
106 	int err;
107 
108 	if (type >= ARRAY_SIZE(bpf_map_types))
109 		return ERR_PTR(-EINVAL);
110 	type = array_index_nospec(type, ARRAY_SIZE(bpf_map_types));
111 	ops = bpf_map_types[type];
112 	if (!ops)
113 		return ERR_PTR(-EINVAL);
114 
115 	if (ops->map_alloc_check) {
116 		err = ops->map_alloc_check(attr);
117 		if (err)
118 			return ERR_PTR(err);
119 	}
120 	if (attr->map_ifindex)
121 		ops = &bpf_map_offload_ops;
122 	map = ops->map_alloc(attr);
123 	if (IS_ERR(map))
124 		return map;
125 	map->ops = ops;
126 	map->map_type = type;
127 	return map;
128 }
129 
bpf_map_area_alloc(u64 size,int numa_node)130 void *bpf_map_area_alloc(u64 size, int numa_node)
131 {
132 	/* We really just want to fail instead of triggering OOM killer
133 	 * under memory pressure, therefore we set __GFP_NORETRY to kmalloc,
134 	 * which is used for lower order allocation requests.
135 	 *
136 	 * It has been observed that higher order allocation requests done by
137 	 * vmalloc with __GFP_NORETRY being set might fail due to not trying
138 	 * to reclaim memory from the page cache, thus we set
139 	 * __GFP_RETRY_MAYFAIL to avoid such situations.
140 	 */
141 
142 	const gfp_t flags = __GFP_NOWARN | __GFP_ZERO;
143 	void *area;
144 
145 	if (size >= SIZE_MAX)
146 		return NULL;
147 
148 	if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) {
149 		area = kmalloc_node(size, GFP_USER | __GFP_NORETRY | flags,
150 				    numa_node);
151 		if (area != NULL)
152 			return area;
153 	}
154 
155 	return __vmalloc_node_flags_caller(size, numa_node,
156 					   GFP_KERNEL | __GFP_RETRY_MAYFAIL |
157 					   flags, __builtin_return_address(0));
158 }
159 
bpf_map_area_free(void * area)160 void bpf_map_area_free(void *area)
161 {
162 	kvfree(area);
163 }
164 
bpf_map_flags_retain_permanent(u32 flags)165 static u32 bpf_map_flags_retain_permanent(u32 flags)
166 {
167 	/* Some map creation flags are not tied to the map object but
168 	 * rather to the map fd instead, so they have no meaning upon
169 	 * map object inspection since multiple file descriptors with
170 	 * different (access) properties can exist here. Thus, given
171 	 * this has zero meaning for the map itself, lets clear these
172 	 * from here.
173 	 */
174 	return flags & ~(BPF_F_RDONLY | BPF_F_WRONLY);
175 }
176 
bpf_map_init_from_attr(struct bpf_map * map,union bpf_attr * attr)177 void bpf_map_init_from_attr(struct bpf_map *map, union bpf_attr *attr)
178 {
179 	map->map_type = attr->map_type;
180 	map->key_size = attr->key_size;
181 	map->value_size = attr->value_size;
182 	map->max_entries = attr->max_entries;
183 	map->map_flags = bpf_map_flags_retain_permanent(attr->map_flags);
184 	map->numa_node = bpf_map_attr_numa_node(attr);
185 }
186 
bpf_charge_memlock(struct user_struct * user,u32 pages)187 static int bpf_charge_memlock(struct user_struct *user, u32 pages)
188 {
189 	unsigned long memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
190 
191 	if (atomic_long_add_return(pages, &user->locked_vm) > memlock_limit) {
192 		atomic_long_sub(pages, &user->locked_vm);
193 		return -EPERM;
194 	}
195 	return 0;
196 }
197 
bpf_uncharge_memlock(struct user_struct * user,u32 pages)198 static void bpf_uncharge_memlock(struct user_struct *user, u32 pages)
199 {
200 	if (user)
201 		atomic_long_sub(pages, &user->locked_vm);
202 }
203 
bpf_map_charge_init(struct bpf_map_memory * mem,u64 size)204 int bpf_map_charge_init(struct bpf_map_memory *mem, u64 size)
205 {
206 	u32 pages = round_up(size, PAGE_SIZE) >> PAGE_SHIFT;
207 	struct user_struct *user;
208 	int ret;
209 
210 	if (size >= U32_MAX - PAGE_SIZE)
211 		return -E2BIG;
212 
213 	user = get_current_user();
214 	ret = bpf_charge_memlock(user, pages);
215 	if (ret) {
216 		free_uid(user);
217 		return ret;
218 	}
219 
220 	mem->pages = pages;
221 	mem->user = user;
222 
223 	return 0;
224 }
225 
bpf_map_charge_finish(struct bpf_map_memory * mem)226 void bpf_map_charge_finish(struct bpf_map_memory *mem)
227 {
228 	bpf_uncharge_memlock(mem->user, mem->pages);
229 	free_uid(mem->user);
230 }
231 
bpf_map_charge_move(struct bpf_map_memory * dst,struct bpf_map_memory * src)232 void bpf_map_charge_move(struct bpf_map_memory *dst,
233 			 struct bpf_map_memory *src)
234 {
235 	*dst = *src;
236 
237 	/* Make sure src will not be used for the redundant uncharging. */
238 	memset(src, 0, sizeof(struct bpf_map_memory));
239 }
240 
bpf_map_charge_memlock(struct bpf_map * map,u32 pages)241 int bpf_map_charge_memlock(struct bpf_map *map, u32 pages)
242 {
243 	int ret;
244 
245 	ret = bpf_charge_memlock(map->memory.user, pages);
246 	if (ret)
247 		return ret;
248 	map->memory.pages += pages;
249 	return ret;
250 }
251 
bpf_map_uncharge_memlock(struct bpf_map * map,u32 pages)252 void bpf_map_uncharge_memlock(struct bpf_map *map, u32 pages)
253 {
254 	bpf_uncharge_memlock(map->memory.user, pages);
255 	map->memory.pages -= pages;
256 }
257 
bpf_map_alloc_id(struct bpf_map * map)258 static int bpf_map_alloc_id(struct bpf_map *map)
259 {
260 	int id;
261 
262 	idr_preload(GFP_KERNEL);
263 	spin_lock_bh(&map_idr_lock);
264 	id = idr_alloc_cyclic(&map_idr, map, 1, INT_MAX, GFP_ATOMIC);
265 	if (id > 0)
266 		map->id = id;
267 	spin_unlock_bh(&map_idr_lock);
268 	idr_preload_end();
269 
270 	if (WARN_ON_ONCE(!id))
271 		return -ENOSPC;
272 
273 	return id > 0 ? 0 : id;
274 }
275 
bpf_map_free_id(struct bpf_map * map,bool do_idr_lock)276 void bpf_map_free_id(struct bpf_map *map, bool do_idr_lock)
277 {
278 	unsigned long flags;
279 
280 	/* Offloaded maps are removed from the IDR store when their device
281 	 * disappears - even if someone holds an fd to them they are unusable,
282 	 * the memory is gone, all ops will fail; they are simply waiting for
283 	 * refcnt to drop to be freed.
284 	 */
285 	if (!map->id)
286 		return;
287 
288 	if (do_idr_lock)
289 		spin_lock_irqsave(&map_idr_lock, flags);
290 	else
291 		__acquire(&map_idr_lock);
292 
293 	idr_remove(&map_idr, map->id);
294 	map->id = 0;
295 
296 	if (do_idr_lock)
297 		spin_unlock_irqrestore(&map_idr_lock, flags);
298 	else
299 		__release(&map_idr_lock);
300 }
301 
302 /* called from workqueue */
bpf_map_free_deferred(struct work_struct * work)303 static void bpf_map_free_deferred(struct work_struct *work)
304 {
305 	struct bpf_map *map = container_of(work, struct bpf_map, work);
306 	struct bpf_map_memory mem;
307 
308 	bpf_map_charge_move(&mem, &map->memory);
309 	security_bpf_map_free(map);
310 	/* implementation dependent freeing */
311 	map->ops->map_free(map);
312 	bpf_map_charge_finish(&mem);
313 }
314 
bpf_map_put_uref(struct bpf_map * map)315 static void bpf_map_put_uref(struct bpf_map *map)
316 {
317 	if (atomic_dec_and_test(&map->usercnt)) {
318 		if (map->ops->map_release_uref)
319 			map->ops->map_release_uref(map);
320 	}
321 }
322 
323 /* decrement map refcnt and schedule it for freeing via workqueue
324  * (unrelying map implementation ops->map_free() might sleep)
325  */
__bpf_map_put(struct bpf_map * map,bool do_idr_lock)326 static void __bpf_map_put(struct bpf_map *map, bool do_idr_lock)
327 {
328 	if (atomic_dec_and_test(&map->refcnt)) {
329 		/* bpf_map_free_id() must be called first */
330 		bpf_map_free_id(map, do_idr_lock);
331 		btf_put(map->btf);
332 		INIT_WORK(&map->work, bpf_map_free_deferred);
333 		schedule_work(&map->work);
334 	}
335 }
336 
bpf_map_put(struct bpf_map * map)337 void bpf_map_put(struct bpf_map *map)
338 {
339 	__bpf_map_put(map, true);
340 }
341 EXPORT_SYMBOL_GPL(bpf_map_put);
342 
bpf_map_put_with_uref(struct bpf_map * map)343 void bpf_map_put_with_uref(struct bpf_map *map)
344 {
345 	bpf_map_put_uref(map);
346 	bpf_map_put(map);
347 }
348 
bpf_map_release(struct inode * inode,struct file * filp)349 static int bpf_map_release(struct inode *inode, struct file *filp)
350 {
351 	struct bpf_map *map = filp->private_data;
352 
353 	if (map->ops->map_release)
354 		map->ops->map_release(map, filp);
355 
356 	bpf_map_put_with_uref(map);
357 	return 0;
358 }
359 
map_get_sys_perms(struct bpf_map * map,struct fd f)360 static fmode_t map_get_sys_perms(struct bpf_map *map, struct fd f)
361 {
362 	fmode_t mode = f.file->f_mode;
363 
364 	/* Our file permissions may have been overridden by global
365 	 * map permissions facing syscall side.
366 	 */
367 	if (READ_ONCE(map->frozen))
368 		mode &= ~FMODE_CAN_WRITE;
369 	return mode;
370 }
371 
372 #ifdef CONFIG_PROC_FS
bpf_map_show_fdinfo(struct seq_file * m,struct file * filp)373 static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp)
374 {
375 	const struct bpf_map *map = filp->private_data;
376 	const struct bpf_array *array;
377 	u32 owner_prog_type = 0;
378 	u32 owner_jited = 0;
379 
380 	if (map->map_type == BPF_MAP_TYPE_PROG_ARRAY) {
381 		array = container_of(map, struct bpf_array, map);
382 		owner_prog_type = array->owner_prog_type;
383 		owner_jited = array->owner_jited;
384 	}
385 
386 	seq_printf(m,
387 		   "map_type:\t%u\n"
388 		   "key_size:\t%u\n"
389 		   "value_size:\t%u\n"
390 		   "max_entries:\t%u\n"
391 		   "map_flags:\t%#x\n"
392 		   "memlock:\t%llu\n"
393 		   "map_id:\t%u\n"
394 		   "frozen:\t%u\n",
395 		   map->map_type,
396 		   map->key_size,
397 		   map->value_size,
398 		   map->max_entries,
399 		   map->map_flags,
400 		   map->memory.pages * 1ULL << PAGE_SHIFT,
401 		   map->id,
402 		   READ_ONCE(map->frozen));
403 
404 	if (owner_prog_type) {
405 		seq_printf(m, "owner_prog_type:\t%u\n",
406 			   owner_prog_type);
407 		seq_printf(m, "owner_jited:\t%u\n",
408 			   owner_jited);
409 	}
410 }
411 #endif
412 
bpf_dummy_read(struct file * filp,char __user * buf,size_t siz,loff_t * ppos)413 static ssize_t bpf_dummy_read(struct file *filp, char __user *buf, size_t siz,
414 			      loff_t *ppos)
415 {
416 	/* We need this handler such that alloc_file() enables
417 	 * f_mode with FMODE_CAN_READ.
418 	 */
419 	return -EINVAL;
420 }
421 
bpf_dummy_write(struct file * filp,const char __user * buf,size_t siz,loff_t * ppos)422 static ssize_t bpf_dummy_write(struct file *filp, const char __user *buf,
423 			       size_t siz, loff_t *ppos)
424 {
425 	/* We need this handler such that alloc_file() enables
426 	 * f_mode with FMODE_CAN_WRITE.
427 	 */
428 	return -EINVAL;
429 }
430 
431 const struct file_operations bpf_map_fops = {
432 #ifdef CONFIG_PROC_FS
433 	.show_fdinfo	= bpf_map_show_fdinfo,
434 #endif
435 	.release	= bpf_map_release,
436 	.read		= bpf_dummy_read,
437 	.write		= bpf_dummy_write,
438 };
439 
bpf_map_new_fd(struct bpf_map * map,int flags)440 int bpf_map_new_fd(struct bpf_map *map, int flags)
441 {
442 	int ret;
443 
444 	ret = security_bpf_map(map, OPEN_FMODE(flags));
445 	if (ret < 0)
446 		return ret;
447 
448 	return anon_inode_getfd("bpf-map", &bpf_map_fops, map,
449 				flags | O_CLOEXEC);
450 }
451 
bpf_get_file_flag(int flags)452 int bpf_get_file_flag(int flags)
453 {
454 	if ((flags & BPF_F_RDONLY) && (flags & BPF_F_WRONLY))
455 		return -EINVAL;
456 	if (flags & BPF_F_RDONLY)
457 		return O_RDONLY;
458 	if (flags & BPF_F_WRONLY)
459 		return O_WRONLY;
460 	return O_RDWR;
461 }
462 
463 /* helper macro to check that unused fields 'union bpf_attr' are zero */
464 #define CHECK_ATTR(CMD) \
465 	memchr_inv((void *) &attr->CMD##_LAST_FIELD + \
466 		   sizeof(attr->CMD##_LAST_FIELD), 0, \
467 		   sizeof(*attr) - \
468 		   offsetof(union bpf_attr, CMD##_LAST_FIELD) - \
469 		   sizeof(attr->CMD##_LAST_FIELD)) != NULL
470 
471 /* dst and src must have at least BPF_OBJ_NAME_LEN number of bytes.
472  * Return 0 on success and < 0 on error.
473  */
bpf_obj_name_cpy(char * dst,const char * src)474 static int bpf_obj_name_cpy(char *dst, const char *src)
475 {
476 	const char *end = src + BPF_OBJ_NAME_LEN;
477 
478 	memset(dst, 0, BPF_OBJ_NAME_LEN);
479 	/* Copy all isalnum(), '_' and '.' chars. */
480 	while (src < end && *src) {
481 		if (!isalnum(*src) &&
482 		    *src != '_' && *src != '.')
483 			return -EINVAL;
484 		*dst++ = *src++;
485 	}
486 
487 	/* No '\0' found in BPF_OBJ_NAME_LEN number of bytes */
488 	if (src == end)
489 		return -EINVAL;
490 
491 	return 0;
492 }
493 
map_check_no_btf(const struct bpf_map * map,const struct btf * btf,const struct btf_type * key_type,const struct btf_type * value_type)494 int map_check_no_btf(const struct bpf_map *map,
495 		     const struct btf *btf,
496 		     const struct btf_type *key_type,
497 		     const struct btf_type *value_type)
498 {
499 	return -ENOTSUPP;
500 }
501 
map_check_btf(struct bpf_map * map,const struct btf * btf,u32 btf_key_id,u32 btf_value_id)502 static int map_check_btf(struct bpf_map *map, const struct btf *btf,
503 			 u32 btf_key_id, u32 btf_value_id)
504 {
505 	const struct btf_type *key_type, *value_type;
506 	u32 key_size, value_size;
507 	int ret = 0;
508 
509 	/* Some maps allow key to be unspecified. */
510 	if (btf_key_id) {
511 		key_type = btf_type_id_size(btf, &btf_key_id, &key_size);
512 		if (!key_type || key_size != map->key_size)
513 			return -EINVAL;
514 	} else {
515 		key_type = btf_type_by_id(btf, 0);
516 		if (!map->ops->map_check_btf)
517 			return -EINVAL;
518 	}
519 
520 	value_type = btf_type_id_size(btf, &btf_value_id, &value_size);
521 	if (!value_type || value_size != map->value_size)
522 		return -EINVAL;
523 
524 	map->spin_lock_off = btf_find_spin_lock(btf, value_type);
525 
526 	if (map_value_has_spin_lock(map)) {
527 		if (map->map_flags & BPF_F_RDONLY_PROG)
528 			return -EACCES;
529 		if (map->map_type != BPF_MAP_TYPE_HASH &&
530 		    map->map_type != BPF_MAP_TYPE_ARRAY &&
531 		    map->map_type != BPF_MAP_TYPE_CGROUP_STORAGE &&
532 		    map->map_type != BPF_MAP_TYPE_SK_STORAGE)
533 			return -ENOTSUPP;
534 		if (map->spin_lock_off + sizeof(struct bpf_spin_lock) >
535 		    map->value_size) {
536 			WARN_ONCE(1,
537 				  "verifier bug spin_lock_off %d value_size %d\n",
538 				  map->spin_lock_off, map->value_size);
539 			return -EFAULT;
540 		}
541 	}
542 
543 	if (map->ops->map_check_btf)
544 		ret = map->ops->map_check_btf(map, btf, key_type, value_type);
545 
546 	return ret;
547 }
548 
549 #define BPF_MAP_CREATE_LAST_FIELD btf_value_type_id
550 /* called via syscall */
map_create(union bpf_attr * attr)551 static int map_create(union bpf_attr *attr)
552 {
553 	int numa_node = bpf_map_attr_numa_node(attr);
554 	struct bpf_map_memory mem;
555 	struct bpf_map *map;
556 	int f_flags;
557 	int err;
558 
559 	err = CHECK_ATTR(BPF_MAP_CREATE);
560 	if (err)
561 		return -EINVAL;
562 
563 	f_flags = bpf_get_file_flag(attr->map_flags);
564 	if (f_flags < 0)
565 		return f_flags;
566 
567 	if (numa_node != NUMA_NO_NODE &&
568 	    ((unsigned int)numa_node >= nr_node_ids ||
569 	     !node_online(numa_node)))
570 		return -EINVAL;
571 
572 	/* find map type and init map: hashtable vs rbtree vs bloom vs ... */
573 	map = find_and_alloc_map(attr);
574 	if (IS_ERR(map))
575 		return PTR_ERR(map);
576 
577 	err = bpf_obj_name_cpy(map->name, attr->map_name);
578 	if (err)
579 		goto free_map;
580 
581 	atomic_set(&map->refcnt, 1);
582 	atomic_set(&map->usercnt, 1);
583 
584 	if (attr->btf_key_type_id || attr->btf_value_type_id) {
585 		struct btf *btf;
586 
587 		if (!attr->btf_value_type_id) {
588 			err = -EINVAL;
589 			goto free_map;
590 		}
591 
592 		btf = btf_get_by_fd(attr->btf_fd);
593 		if (IS_ERR(btf)) {
594 			err = PTR_ERR(btf);
595 			goto free_map;
596 		}
597 
598 		err = map_check_btf(map, btf, attr->btf_key_type_id,
599 				    attr->btf_value_type_id);
600 		if (err) {
601 			btf_put(btf);
602 			goto free_map;
603 		}
604 
605 		map->btf = btf;
606 		map->btf_key_type_id = attr->btf_key_type_id;
607 		map->btf_value_type_id = attr->btf_value_type_id;
608 	} else {
609 		map->spin_lock_off = -EINVAL;
610 	}
611 
612 	err = security_bpf_map_alloc(map);
613 	if (err)
614 		goto free_map;
615 
616 	err = bpf_map_alloc_id(map);
617 	if (err)
618 		goto free_map_sec;
619 
620 	err = bpf_map_new_fd(map, f_flags);
621 	if (err < 0) {
622 		/* failed to allocate fd.
623 		 * bpf_map_put_with_uref() is needed because the above
624 		 * bpf_map_alloc_id() has published the map
625 		 * to the userspace and the userspace may
626 		 * have refcnt-ed it through BPF_MAP_GET_FD_BY_ID.
627 		 */
628 		bpf_map_put_with_uref(map);
629 		return err;
630 	}
631 
632 	return err;
633 
634 free_map_sec:
635 	security_bpf_map_free(map);
636 free_map:
637 	btf_put(map->btf);
638 	bpf_map_charge_move(&mem, &map->memory);
639 	map->ops->map_free(map);
640 	bpf_map_charge_finish(&mem);
641 	return err;
642 }
643 
644 /* if error is returned, fd is released.
645  * On success caller should complete fd access with matching fdput()
646  */
__bpf_map_get(struct fd f)647 struct bpf_map *__bpf_map_get(struct fd f)
648 {
649 	if (!f.file)
650 		return ERR_PTR(-EBADF);
651 	if (f.file->f_op != &bpf_map_fops) {
652 		fdput(f);
653 		return ERR_PTR(-EINVAL);
654 	}
655 
656 	return f.file->private_data;
657 }
658 
659 /* prog's and map's refcnt limit */
660 #define BPF_MAX_REFCNT 32768
661 
bpf_map_inc(struct bpf_map * map,bool uref)662 struct bpf_map *bpf_map_inc(struct bpf_map *map, bool uref)
663 {
664 	if (atomic_inc_return(&map->refcnt) > BPF_MAX_REFCNT) {
665 		atomic_dec(&map->refcnt);
666 		return ERR_PTR(-EBUSY);
667 	}
668 	if (uref)
669 		atomic_inc(&map->usercnt);
670 	return map;
671 }
672 EXPORT_SYMBOL_GPL(bpf_map_inc);
673 
bpf_map_get_with_uref(u32 ufd)674 struct bpf_map *bpf_map_get_with_uref(u32 ufd)
675 {
676 	struct fd f = fdget(ufd);
677 	struct bpf_map *map;
678 
679 	map = __bpf_map_get(f);
680 	if (IS_ERR(map))
681 		return map;
682 
683 	map = bpf_map_inc(map, true);
684 	fdput(f);
685 
686 	return map;
687 }
688 
689 /* map_idr_lock should have been held */
__bpf_map_inc_not_zero(struct bpf_map * map,bool uref)690 static struct bpf_map *__bpf_map_inc_not_zero(struct bpf_map *map,
691 					      bool uref)
692 {
693 	int refold;
694 
695 	refold = atomic_fetch_add_unless(&map->refcnt, 1, 0);
696 
697 	if (refold >= BPF_MAX_REFCNT) {
698 		__bpf_map_put(map, false);
699 		return ERR_PTR(-EBUSY);
700 	}
701 
702 	if (!refold)
703 		return ERR_PTR(-ENOENT);
704 
705 	if (uref)
706 		atomic_inc(&map->usercnt);
707 
708 	return map;
709 }
710 
bpf_map_inc_not_zero(struct bpf_map * map,bool uref)711 struct bpf_map *bpf_map_inc_not_zero(struct bpf_map *map, bool uref)
712 {
713 	spin_lock_bh(&map_idr_lock);
714 	map = __bpf_map_inc_not_zero(map, uref);
715 	spin_unlock_bh(&map_idr_lock);
716 
717 	return map;
718 }
719 EXPORT_SYMBOL_GPL(bpf_map_inc_not_zero);
720 
bpf_stackmap_copy(struct bpf_map * map,void * key,void * value)721 int __weak bpf_stackmap_copy(struct bpf_map *map, void *key, void *value)
722 {
723 	return -ENOTSUPP;
724 }
725 
__bpf_copy_key(void __user * ukey,u64 key_size)726 static void *__bpf_copy_key(void __user *ukey, u64 key_size)
727 {
728 	if (key_size)
729 		return memdup_user(ukey, key_size);
730 
731 	if (ukey)
732 		return ERR_PTR(-EINVAL);
733 
734 	return NULL;
735 }
736 
737 /* last field in 'union bpf_attr' used by this command */
738 #define BPF_MAP_LOOKUP_ELEM_LAST_FIELD flags
739 
map_lookup_elem(union bpf_attr * attr)740 static int map_lookup_elem(union bpf_attr *attr)
741 {
742 	void __user *ukey = u64_to_user_ptr(attr->key);
743 	void __user *uvalue = u64_to_user_ptr(attr->value);
744 	int ufd = attr->map_fd;
745 	struct bpf_map *map;
746 	void *key, *value, *ptr;
747 	u32 value_size;
748 	struct fd f;
749 	int err;
750 
751 	if (CHECK_ATTR(BPF_MAP_LOOKUP_ELEM))
752 		return -EINVAL;
753 
754 	if (attr->flags & ~BPF_F_LOCK)
755 		return -EINVAL;
756 
757 	f = fdget(ufd);
758 	map = __bpf_map_get(f);
759 	if (IS_ERR(map))
760 		return PTR_ERR(map);
761 	if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) {
762 		err = -EPERM;
763 		goto err_put;
764 	}
765 
766 	if ((attr->flags & BPF_F_LOCK) &&
767 	    !map_value_has_spin_lock(map)) {
768 		err = -EINVAL;
769 		goto err_put;
770 	}
771 
772 	key = __bpf_copy_key(ukey, map->key_size);
773 	if (IS_ERR(key)) {
774 		err = PTR_ERR(key);
775 		goto err_put;
776 	}
777 
778 	if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
779 	    map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH ||
780 	    map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY ||
781 	    map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE)
782 		value_size = round_up(map->value_size, 8) * num_possible_cpus();
783 	else if (IS_FD_MAP(map))
784 		value_size = sizeof(u32);
785 	else
786 		value_size = map->value_size;
787 
788 	err = -ENOMEM;
789 	value = kmalloc(value_size, GFP_USER | __GFP_NOWARN);
790 	if (!value)
791 		goto free_key;
792 
793 	if (bpf_map_is_dev_bound(map)) {
794 		err = bpf_map_offload_lookup_elem(map, key, value);
795 		goto done;
796 	}
797 
798 	preempt_disable();
799 	this_cpu_inc(bpf_prog_active);
800 	if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
801 	    map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
802 		err = bpf_percpu_hash_copy(map, key, value);
803 	} else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) {
804 		err = bpf_percpu_array_copy(map, key, value);
805 	} else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) {
806 		err = bpf_percpu_cgroup_storage_copy(map, key, value);
807 	} else if (map->map_type == BPF_MAP_TYPE_STACK_TRACE) {
808 		err = bpf_stackmap_copy(map, key, value);
809 	} else if (IS_FD_ARRAY(map)) {
810 		err = bpf_fd_array_map_lookup_elem(map, key, value);
811 	} else if (IS_FD_HASH(map)) {
812 		err = bpf_fd_htab_map_lookup_elem(map, key, value);
813 	} else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) {
814 		err = bpf_fd_reuseport_array_lookup_elem(map, key, value);
815 	} else if (map->map_type == BPF_MAP_TYPE_QUEUE ||
816 		   map->map_type == BPF_MAP_TYPE_STACK) {
817 		err = map->ops->map_peek_elem(map, value);
818 	} else {
819 		rcu_read_lock();
820 		if (map->ops->map_lookup_elem_sys_only)
821 			ptr = map->ops->map_lookup_elem_sys_only(map, key);
822 		else
823 			ptr = map->ops->map_lookup_elem(map, key);
824 		if (IS_ERR(ptr)) {
825 			err = PTR_ERR(ptr);
826 		} else if (!ptr) {
827 			err = -ENOENT;
828 		} else {
829 			err = 0;
830 			if (attr->flags & BPF_F_LOCK)
831 				/* lock 'ptr' and copy everything but lock */
832 				copy_map_value_locked(map, value, ptr, true);
833 			else
834 				copy_map_value(map, value, ptr);
835 			/* mask lock, since value wasn't zero inited */
836 			check_and_init_map_lock(map, value);
837 		}
838 		rcu_read_unlock();
839 	}
840 	this_cpu_dec(bpf_prog_active);
841 	preempt_enable();
842 
843 done:
844 	if (err)
845 		goto free_value;
846 
847 	err = -EFAULT;
848 	if (copy_to_user(uvalue, value, value_size) != 0)
849 		goto free_value;
850 
851 	err = 0;
852 
853 free_value:
854 	kfree(value);
855 free_key:
856 	kfree(key);
857 err_put:
858 	fdput(f);
859 	return err;
860 }
861 
maybe_wait_bpf_programs(struct bpf_map * map)862 static void maybe_wait_bpf_programs(struct bpf_map *map)
863 {
864 	/* Wait for any running BPF programs to complete so that
865 	 * userspace, when we return to it, knows that all programs
866 	 * that could be running use the new map value.
867 	 */
868 	if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS ||
869 	    map->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS)
870 		synchronize_rcu();
871 }
872 
873 #define BPF_MAP_UPDATE_ELEM_LAST_FIELD flags
874 
map_update_elem(union bpf_attr * attr)875 static int map_update_elem(union bpf_attr *attr)
876 {
877 	void __user *ukey = u64_to_user_ptr(attr->key);
878 	void __user *uvalue = u64_to_user_ptr(attr->value);
879 	int ufd = attr->map_fd;
880 	struct bpf_map *map;
881 	void *key, *value;
882 	u32 value_size;
883 	struct fd f;
884 	int err;
885 
886 	if (CHECK_ATTR(BPF_MAP_UPDATE_ELEM))
887 		return -EINVAL;
888 
889 	f = fdget(ufd);
890 	map = __bpf_map_get(f);
891 	if (IS_ERR(map))
892 		return PTR_ERR(map);
893 	if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
894 		err = -EPERM;
895 		goto err_put;
896 	}
897 
898 	if ((attr->flags & BPF_F_LOCK) &&
899 	    !map_value_has_spin_lock(map)) {
900 		err = -EINVAL;
901 		goto err_put;
902 	}
903 
904 	key = __bpf_copy_key(ukey, map->key_size);
905 	if (IS_ERR(key)) {
906 		err = PTR_ERR(key);
907 		goto err_put;
908 	}
909 
910 	if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
911 	    map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH ||
912 	    map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY ||
913 	    map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE)
914 		value_size = round_up(map->value_size, 8) * num_possible_cpus();
915 	else
916 		value_size = map->value_size;
917 
918 	err = -ENOMEM;
919 	value = kmalloc(value_size, GFP_USER | __GFP_NOWARN);
920 	if (!value)
921 		goto free_key;
922 
923 	err = -EFAULT;
924 	if (copy_from_user(value, uvalue, value_size) != 0)
925 		goto free_value;
926 
927 	/* Need to create a kthread, thus must support schedule */
928 	if (bpf_map_is_dev_bound(map)) {
929 		err = bpf_map_offload_update_elem(map, key, value, attr->flags);
930 		goto out;
931 	} else if (map->map_type == BPF_MAP_TYPE_CPUMAP ||
932 		   map->map_type == BPF_MAP_TYPE_SOCKHASH ||
933 		   map->map_type == BPF_MAP_TYPE_SOCKMAP) {
934 		err = map->ops->map_update_elem(map, key, value, attr->flags);
935 		goto out;
936 	}
937 
938 	/* must increment bpf_prog_active to avoid kprobe+bpf triggering from
939 	 * inside bpf map update or delete otherwise deadlocks are possible
940 	 */
941 	preempt_disable();
942 	__this_cpu_inc(bpf_prog_active);
943 	if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
944 	    map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
945 		err = bpf_percpu_hash_update(map, key, value, attr->flags);
946 	} else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) {
947 		err = bpf_percpu_array_update(map, key, value, attr->flags);
948 	} else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) {
949 		err = bpf_percpu_cgroup_storage_update(map, key, value,
950 						       attr->flags);
951 	} else if (IS_FD_ARRAY(map)) {
952 		rcu_read_lock();
953 		err = bpf_fd_array_map_update_elem(map, f.file, key, value,
954 						   attr->flags);
955 		rcu_read_unlock();
956 	} else if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) {
957 		rcu_read_lock();
958 		err = bpf_fd_htab_map_update_elem(map, f.file, key, value,
959 						  attr->flags);
960 		rcu_read_unlock();
961 	} else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) {
962 		/* rcu_read_lock() is not needed */
963 		err = bpf_fd_reuseport_array_update_elem(map, key, value,
964 							 attr->flags);
965 	} else if (map->map_type == BPF_MAP_TYPE_QUEUE ||
966 		   map->map_type == BPF_MAP_TYPE_STACK) {
967 		err = map->ops->map_push_elem(map, value, attr->flags);
968 	} else {
969 		rcu_read_lock();
970 		err = map->ops->map_update_elem(map, key, value, attr->flags);
971 		rcu_read_unlock();
972 	}
973 	__this_cpu_dec(bpf_prog_active);
974 	preempt_enable();
975 	maybe_wait_bpf_programs(map);
976 out:
977 free_value:
978 	kfree(value);
979 free_key:
980 	kfree(key);
981 err_put:
982 	fdput(f);
983 	return err;
984 }
985 
986 #define BPF_MAP_DELETE_ELEM_LAST_FIELD key
987 
map_delete_elem(union bpf_attr * attr)988 static int map_delete_elem(union bpf_attr *attr)
989 {
990 	void __user *ukey = u64_to_user_ptr(attr->key);
991 	int ufd = attr->map_fd;
992 	struct bpf_map *map;
993 	struct fd f;
994 	void *key;
995 	int err;
996 
997 	if (CHECK_ATTR(BPF_MAP_DELETE_ELEM))
998 		return -EINVAL;
999 
1000 	f = fdget(ufd);
1001 	map = __bpf_map_get(f);
1002 	if (IS_ERR(map))
1003 		return PTR_ERR(map);
1004 	if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
1005 		err = -EPERM;
1006 		goto err_put;
1007 	}
1008 
1009 	key = __bpf_copy_key(ukey, map->key_size);
1010 	if (IS_ERR(key)) {
1011 		err = PTR_ERR(key);
1012 		goto err_put;
1013 	}
1014 
1015 	if (bpf_map_is_dev_bound(map)) {
1016 		err = bpf_map_offload_delete_elem(map, key);
1017 		goto out;
1018 	}
1019 
1020 	preempt_disable();
1021 	__this_cpu_inc(bpf_prog_active);
1022 	rcu_read_lock();
1023 	err = map->ops->map_delete_elem(map, key);
1024 	rcu_read_unlock();
1025 	__this_cpu_dec(bpf_prog_active);
1026 	preempt_enable();
1027 	maybe_wait_bpf_programs(map);
1028 out:
1029 	kfree(key);
1030 err_put:
1031 	fdput(f);
1032 	return err;
1033 }
1034 
1035 /* last field in 'union bpf_attr' used by this command */
1036 #define BPF_MAP_GET_NEXT_KEY_LAST_FIELD next_key
1037 
map_get_next_key(union bpf_attr * attr)1038 static int map_get_next_key(union bpf_attr *attr)
1039 {
1040 	void __user *ukey = u64_to_user_ptr(attr->key);
1041 	void __user *unext_key = u64_to_user_ptr(attr->next_key);
1042 	int ufd = attr->map_fd;
1043 	struct bpf_map *map;
1044 	void *key, *next_key;
1045 	struct fd f;
1046 	int err;
1047 
1048 	if (CHECK_ATTR(BPF_MAP_GET_NEXT_KEY))
1049 		return -EINVAL;
1050 
1051 	f = fdget(ufd);
1052 	map = __bpf_map_get(f);
1053 	if (IS_ERR(map))
1054 		return PTR_ERR(map);
1055 	if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) {
1056 		err = -EPERM;
1057 		goto err_put;
1058 	}
1059 
1060 	if (ukey) {
1061 		key = __bpf_copy_key(ukey, map->key_size);
1062 		if (IS_ERR(key)) {
1063 			err = PTR_ERR(key);
1064 			goto err_put;
1065 		}
1066 	} else {
1067 		key = NULL;
1068 	}
1069 
1070 	err = -ENOMEM;
1071 	next_key = kmalloc(map->key_size, GFP_USER);
1072 	if (!next_key)
1073 		goto free_key;
1074 
1075 	if (bpf_map_is_dev_bound(map)) {
1076 		err = bpf_map_offload_get_next_key(map, key, next_key);
1077 		goto out;
1078 	}
1079 
1080 	rcu_read_lock();
1081 	err = map->ops->map_get_next_key(map, key, next_key);
1082 	rcu_read_unlock();
1083 out:
1084 	if (err)
1085 		goto free_next_key;
1086 
1087 	err = -EFAULT;
1088 	if (copy_to_user(unext_key, next_key, map->key_size) != 0)
1089 		goto free_next_key;
1090 
1091 	err = 0;
1092 
1093 free_next_key:
1094 	kfree(next_key);
1095 free_key:
1096 	kfree(key);
1097 err_put:
1098 	fdput(f);
1099 	return err;
1100 }
1101 
1102 #define BPF_MAP_LOOKUP_AND_DELETE_ELEM_LAST_FIELD value
1103 
map_lookup_and_delete_elem(union bpf_attr * attr)1104 static int map_lookup_and_delete_elem(union bpf_attr *attr)
1105 {
1106 	void __user *ukey = u64_to_user_ptr(attr->key);
1107 	void __user *uvalue = u64_to_user_ptr(attr->value);
1108 	int ufd = attr->map_fd;
1109 	struct bpf_map *map;
1110 	void *key, *value;
1111 	u32 value_size;
1112 	struct fd f;
1113 	int err;
1114 
1115 	if (CHECK_ATTR(BPF_MAP_LOOKUP_AND_DELETE_ELEM))
1116 		return -EINVAL;
1117 
1118 	f = fdget(ufd);
1119 	map = __bpf_map_get(f);
1120 	if (IS_ERR(map))
1121 		return PTR_ERR(map);
1122 	if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ) ||
1123 	    !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
1124 		err = -EPERM;
1125 		goto err_put;
1126 	}
1127 
1128 	key = __bpf_copy_key(ukey, map->key_size);
1129 	if (IS_ERR(key)) {
1130 		err = PTR_ERR(key);
1131 		goto err_put;
1132 	}
1133 
1134 	value_size = map->value_size;
1135 
1136 	err = -ENOMEM;
1137 	value = kmalloc(value_size, GFP_USER | __GFP_NOWARN);
1138 	if (!value)
1139 		goto free_key;
1140 
1141 	if (map->map_type == BPF_MAP_TYPE_QUEUE ||
1142 	    map->map_type == BPF_MAP_TYPE_STACK) {
1143 		err = map->ops->map_pop_elem(map, value);
1144 	} else {
1145 		err = -ENOTSUPP;
1146 	}
1147 
1148 	if (err)
1149 		goto free_value;
1150 
1151 	if (copy_to_user(uvalue, value, value_size) != 0) {
1152 		err = -EFAULT;
1153 		goto free_value;
1154 	}
1155 
1156 	err = 0;
1157 
1158 free_value:
1159 	kfree(value);
1160 free_key:
1161 	kfree(key);
1162 err_put:
1163 	fdput(f);
1164 	return err;
1165 }
1166 
1167 #define BPF_MAP_FREEZE_LAST_FIELD map_fd
1168 
map_freeze(const union bpf_attr * attr)1169 static int map_freeze(const union bpf_attr *attr)
1170 {
1171 	int err = 0, ufd = attr->map_fd;
1172 	struct bpf_map *map;
1173 	struct fd f;
1174 
1175 	if (CHECK_ATTR(BPF_MAP_FREEZE))
1176 		return -EINVAL;
1177 
1178 	f = fdget(ufd);
1179 	map = __bpf_map_get(f);
1180 	if (IS_ERR(map))
1181 		return PTR_ERR(map);
1182 	if (READ_ONCE(map->frozen)) {
1183 		err = -EBUSY;
1184 		goto err_put;
1185 	}
1186 	if (!capable(CAP_SYS_ADMIN)) {
1187 		err = -EPERM;
1188 		goto err_put;
1189 	}
1190 
1191 	WRITE_ONCE(map->frozen, true);
1192 err_put:
1193 	fdput(f);
1194 	return err;
1195 }
1196 
1197 static const struct bpf_prog_ops * const bpf_prog_types[] = {
1198 #define BPF_PROG_TYPE(_id, _name) \
1199 	[_id] = & _name ## _prog_ops,
1200 #define BPF_MAP_TYPE(_id, _ops)
1201 #include <linux/bpf_types.h>
1202 #undef BPF_PROG_TYPE
1203 #undef BPF_MAP_TYPE
1204 };
1205 
find_prog_type(enum bpf_prog_type type,struct bpf_prog * prog)1206 static int find_prog_type(enum bpf_prog_type type, struct bpf_prog *prog)
1207 {
1208 	const struct bpf_prog_ops *ops;
1209 
1210 	if (type >= ARRAY_SIZE(bpf_prog_types))
1211 		return -EINVAL;
1212 	type = array_index_nospec(type, ARRAY_SIZE(bpf_prog_types));
1213 	ops = bpf_prog_types[type];
1214 	if (!ops)
1215 		return -EINVAL;
1216 
1217 	if (!bpf_prog_is_dev_bound(prog->aux))
1218 		prog->aux->ops = ops;
1219 	else
1220 		prog->aux->ops = &bpf_offload_prog_ops;
1221 	prog->type = type;
1222 	return 0;
1223 }
1224 
1225 /* drop refcnt on maps used by eBPF program and free auxilary data */
free_used_maps(struct bpf_prog_aux * aux)1226 static void free_used_maps(struct bpf_prog_aux *aux)
1227 {
1228 	enum bpf_cgroup_storage_type stype;
1229 	int i;
1230 
1231 	for_each_cgroup_storage_type(stype) {
1232 		if (!aux->cgroup_storage[stype])
1233 			continue;
1234 		bpf_cgroup_storage_release(aux->prog,
1235 					   aux->cgroup_storage[stype]);
1236 	}
1237 
1238 	for (i = 0; i < aux->used_map_cnt; i++)
1239 		bpf_map_put(aux->used_maps[i]);
1240 
1241 	kfree(aux->used_maps);
1242 }
1243 
__bpf_prog_charge(struct user_struct * user,u32 pages)1244 int __bpf_prog_charge(struct user_struct *user, u32 pages)
1245 {
1246 	unsigned long memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
1247 	unsigned long user_bufs;
1248 
1249 	if (user) {
1250 		user_bufs = atomic_long_add_return(pages, &user->locked_vm);
1251 		if (user_bufs > memlock_limit) {
1252 			atomic_long_sub(pages, &user->locked_vm);
1253 			return -EPERM;
1254 		}
1255 	}
1256 
1257 	return 0;
1258 }
1259 
__bpf_prog_uncharge(struct user_struct * user,u32 pages)1260 void __bpf_prog_uncharge(struct user_struct *user, u32 pages)
1261 {
1262 	if (user)
1263 		atomic_long_sub(pages, &user->locked_vm);
1264 }
1265 
bpf_prog_charge_memlock(struct bpf_prog * prog)1266 static int bpf_prog_charge_memlock(struct bpf_prog *prog)
1267 {
1268 	struct user_struct *user = get_current_user();
1269 	int ret;
1270 
1271 	ret = __bpf_prog_charge(user, prog->pages);
1272 	if (ret) {
1273 		free_uid(user);
1274 		return ret;
1275 	}
1276 
1277 	prog->aux->user = user;
1278 	return 0;
1279 }
1280 
bpf_prog_uncharge_memlock(struct bpf_prog * prog)1281 static void bpf_prog_uncharge_memlock(struct bpf_prog *prog)
1282 {
1283 	struct user_struct *user = prog->aux->user;
1284 
1285 	__bpf_prog_uncharge(user, prog->pages);
1286 	free_uid(user);
1287 }
1288 
bpf_prog_alloc_id(struct bpf_prog * prog)1289 static int bpf_prog_alloc_id(struct bpf_prog *prog)
1290 {
1291 	int id;
1292 
1293 	idr_preload(GFP_KERNEL);
1294 	spin_lock_bh(&prog_idr_lock);
1295 	id = idr_alloc_cyclic(&prog_idr, prog, 1, INT_MAX, GFP_ATOMIC);
1296 	if (id > 0)
1297 		prog->aux->id = id;
1298 	spin_unlock_bh(&prog_idr_lock);
1299 	idr_preload_end();
1300 
1301 	/* id is in [1, INT_MAX) */
1302 	if (WARN_ON_ONCE(!id))
1303 		return -ENOSPC;
1304 
1305 	return id > 0 ? 0 : id;
1306 }
1307 
bpf_prog_free_id(struct bpf_prog * prog,bool do_idr_lock)1308 void bpf_prog_free_id(struct bpf_prog *prog, bool do_idr_lock)
1309 {
1310 	/* cBPF to eBPF migrations are currently not in the idr store.
1311 	 * Offloaded programs are removed from the store when their device
1312 	 * disappears - even if someone grabs an fd to them they are unusable,
1313 	 * simply waiting for refcnt to drop to be freed.
1314 	 */
1315 	if (!prog->aux->id)
1316 		return;
1317 
1318 	if (do_idr_lock)
1319 		spin_lock_bh(&prog_idr_lock);
1320 	else
1321 		__acquire(&prog_idr_lock);
1322 
1323 	idr_remove(&prog_idr, prog->aux->id);
1324 	prog->aux->id = 0;
1325 
1326 	if (do_idr_lock)
1327 		spin_unlock_bh(&prog_idr_lock);
1328 	else
1329 		__release(&prog_idr_lock);
1330 }
1331 
__bpf_prog_put_rcu(struct rcu_head * rcu)1332 static void __bpf_prog_put_rcu(struct rcu_head *rcu)
1333 {
1334 	struct bpf_prog_aux *aux = container_of(rcu, struct bpf_prog_aux, rcu);
1335 
1336 	kvfree(aux->func_info);
1337 	free_used_maps(aux);
1338 	bpf_prog_uncharge_memlock(aux->prog);
1339 	security_bpf_prog_free(aux);
1340 	bpf_prog_free(aux->prog);
1341 }
1342 
__bpf_prog_put_noref(struct bpf_prog * prog,bool deferred)1343 static void __bpf_prog_put_noref(struct bpf_prog *prog, bool deferred)
1344 {
1345 	bpf_prog_kallsyms_del_all(prog);
1346 	btf_put(prog->aux->btf);
1347 	bpf_prog_free_linfo(prog);
1348 
1349 	if (deferred)
1350 		call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu);
1351 	else
1352 		__bpf_prog_put_rcu(&prog->aux->rcu);
1353 }
1354 
__bpf_prog_put(struct bpf_prog * prog,bool do_idr_lock)1355 static void __bpf_prog_put(struct bpf_prog *prog, bool do_idr_lock)
1356 {
1357 	if (atomic_dec_and_test(&prog->aux->refcnt)) {
1358 		perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_UNLOAD, 0);
1359 		/* bpf_prog_free_id() must be called first */
1360 		bpf_prog_free_id(prog, do_idr_lock);
1361 		__bpf_prog_put_noref(prog, true);
1362 	}
1363 }
1364 
bpf_prog_put(struct bpf_prog * prog)1365 void bpf_prog_put(struct bpf_prog *prog)
1366 {
1367 	__bpf_prog_put(prog, true);
1368 }
1369 EXPORT_SYMBOL_GPL(bpf_prog_put);
1370 
bpf_prog_release(struct inode * inode,struct file * filp)1371 static int bpf_prog_release(struct inode *inode, struct file *filp)
1372 {
1373 	struct bpf_prog *prog = filp->private_data;
1374 
1375 	bpf_prog_put(prog);
1376 	return 0;
1377 }
1378 
bpf_prog_get_stats(const struct bpf_prog * prog,struct bpf_prog_stats * stats)1379 static void bpf_prog_get_stats(const struct bpf_prog *prog,
1380 			       struct bpf_prog_stats *stats)
1381 {
1382 	u64 nsecs = 0, cnt = 0;
1383 	int cpu;
1384 
1385 	for_each_possible_cpu(cpu) {
1386 		const struct bpf_prog_stats *st;
1387 		unsigned int start;
1388 		u64 tnsecs, tcnt;
1389 
1390 		st = per_cpu_ptr(prog->aux->stats, cpu);
1391 		do {
1392 			start = u64_stats_fetch_begin_irq(&st->syncp);
1393 			tnsecs = st->nsecs;
1394 			tcnt = st->cnt;
1395 		} while (u64_stats_fetch_retry_irq(&st->syncp, start));
1396 		nsecs += tnsecs;
1397 		cnt += tcnt;
1398 	}
1399 	stats->nsecs = nsecs;
1400 	stats->cnt = cnt;
1401 }
1402 
1403 #ifdef CONFIG_PROC_FS
bpf_prog_show_fdinfo(struct seq_file * m,struct file * filp)1404 static void bpf_prog_show_fdinfo(struct seq_file *m, struct file *filp)
1405 {
1406 	const struct bpf_prog *prog = filp->private_data;
1407 	char prog_tag[sizeof(prog->tag) * 2 + 1] = { };
1408 	struct bpf_prog_stats stats;
1409 
1410 	bpf_prog_get_stats(prog, &stats);
1411 	bin2hex(prog_tag, prog->tag, sizeof(prog->tag));
1412 	seq_printf(m,
1413 		   "prog_type:\t%u\n"
1414 		   "prog_jited:\t%u\n"
1415 		   "prog_tag:\t%s\n"
1416 		   "memlock:\t%llu\n"
1417 		   "prog_id:\t%u\n"
1418 		   "run_time_ns:\t%llu\n"
1419 		   "run_cnt:\t%llu\n",
1420 		   prog->type,
1421 		   prog->jited,
1422 		   prog_tag,
1423 		   prog->pages * 1ULL << PAGE_SHIFT,
1424 		   prog->aux->id,
1425 		   stats.nsecs,
1426 		   stats.cnt);
1427 }
1428 #endif
1429 
1430 const struct file_operations bpf_prog_fops = {
1431 #ifdef CONFIG_PROC_FS
1432 	.show_fdinfo	= bpf_prog_show_fdinfo,
1433 #endif
1434 	.release	= bpf_prog_release,
1435 	.read		= bpf_dummy_read,
1436 	.write		= bpf_dummy_write,
1437 };
1438 
bpf_prog_new_fd(struct bpf_prog * prog)1439 int bpf_prog_new_fd(struct bpf_prog *prog)
1440 {
1441 	int ret;
1442 
1443 	ret = security_bpf_prog(prog);
1444 	if (ret < 0)
1445 		return ret;
1446 
1447 	return anon_inode_getfd("bpf-prog", &bpf_prog_fops, prog,
1448 				O_RDWR | O_CLOEXEC);
1449 }
1450 
____bpf_prog_get(struct fd f)1451 static struct bpf_prog *____bpf_prog_get(struct fd f)
1452 {
1453 	if (!f.file)
1454 		return ERR_PTR(-EBADF);
1455 	if (f.file->f_op != &bpf_prog_fops) {
1456 		fdput(f);
1457 		return ERR_PTR(-EINVAL);
1458 	}
1459 
1460 	return f.file->private_data;
1461 }
1462 
bpf_prog_add(struct bpf_prog * prog,int i)1463 struct bpf_prog *bpf_prog_add(struct bpf_prog *prog, int i)
1464 {
1465 	if (atomic_add_return(i, &prog->aux->refcnt) > BPF_MAX_REFCNT) {
1466 		atomic_sub(i, &prog->aux->refcnt);
1467 		return ERR_PTR(-EBUSY);
1468 	}
1469 	return prog;
1470 }
1471 EXPORT_SYMBOL_GPL(bpf_prog_add);
1472 
bpf_prog_sub(struct bpf_prog * prog,int i)1473 void bpf_prog_sub(struct bpf_prog *prog, int i)
1474 {
1475 	/* Only to be used for undoing previous bpf_prog_add() in some
1476 	 * error path. We still know that another entity in our call
1477 	 * path holds a reference to the program, thus atomic_sub() can
1478 	 * be safely used in such cases!
1479 	 */
1480 	WARN_ON(atomic_sub_return(i, &prog->aux->refcnt) == 0);
1481 }
1482 EXPORT_SYMBOL_GPL(bpf_prog_sub);
1483 
bpf_prog_inc(struct bpf_prog * prog)1484 struct bpf_prog *bpf_prog_inc(struct bpf_prog *prog)
1485 {
1486 	return bpf_prog_add(prog, 1);
1487 }
1488 EXPORT_SYMBOL_GPL(bpf_prog_inc);
1489 
1490 /* prog_idr_lock should have been held */
bpf_prog_inc_not_zero(struct bpf_prog * prog)1491 struct bpf_prog *bpf_prog_inc_not_zero(struct bpf_prog *prog)
1492 {
1493 	int refold;
1494 
1495 	refold = atomic_fetch_add_unless(&prog->aux->refcnt, 1, 0);
1496 
1497 	if (refold >= BPF_MAX_REFCNT) {
1498 		__bpf_prog_put(prog, false);
1499 		return ERR_PTR(-EBUSY);
1500 	}
1501 
1502 	if (!refold)
1503 		return ERR_PTR(-ENOENT);
1504 
1505 	return prog;
1506 }
1507 EXPORT_SYMBOL_GPL(bpf_prog_inc_not_zero);
1508 
bpf_prog_get_ok(struct bpf_prog * prog,enum bpf_prog_type * attach_type,bool attach_drv)1509 bool bpf_prog_get_ok(struct bpf_prog *prog,
1510 			    enum bpf_prog_type *attach_type, bool attach_drv)
1511 {
1512 	/* not an attachment, just a refcount inc, always allow */
1513 	if (!attach_type)
1514 		return true;
1515 
1516 	if (prog->type != *attach_type)
1517 		return false;
1518 	if (bpf_prog_is_dev_bound(prog->aux) && !attach_drv)
1519 		return false;
1520 
1521 	return true;
1522 }
1523 
__bpf_prog_get(u32 ufd,enum bpf_prog_type * attach_type,bool attach_drv)1524 static struct bpf_prog *__bpf_prog_get(u32 ufd, enum bpf_prog_type *attach_type,
1525 				       bool attach_drv)
1526 {
1527 	struct fd f = fdget(ufd);
1528 	struct bpf_prog *prog;
1529 
1530 	prog = ____bpf_prog_get(f);
1531 	if (IS_ERR(prog))
1532 		return prog;
1533 	if (!bpf_prog_get_ok(prog, attach_type, attach_drv)) {
1534 		prog = ERR_PTR(-EINVAL);
1535 		goto out;
1536 	}
1537 
1538 	prog = bpf_prog_inc(prog);
1539 out:
1540 	fdput(f);
1541 	return prog;
1542 }
1543 
bpf_prog_get(u32 ufd)1544 struct bpf_prog *bpf_prog_get(u32 ufd)
1545 {
1546 	return __bpf_prog_get(ufd, NULL, false);
1547 }
1548 
bpf_prog_get_type_dev(u32 ufd,enum bpf_prog_type type,bool attach_drv)1549 struct bpf_prog *bpf_prog_get_type_dev(u32 ufd, enum bpf_prog_type type,
1550 				       bool attach_drv)
1551 {
1552 	return __bpf_prog_get(ufd, &type, attach_drv);
1553 }
1554 EXPORT_SYMBOL_GPL(bpf_prog_get_type_dev);
1555 
1556 /* Initially all BPF programs could be loaded w/o specifying
1557  * expected_attach_type. Later for some of them specifying expected_attach_type
1558  * at load time became required so that program could be validated properly.
1559  * Programs of types that are allowed to be loaded both w/ and w/o (for
1560  * backward compatibility) expected_attach_type, should have the default attach
1561  * type assigned to expected_attach_type for the latter case, so that it can be
1562  * validated later at attach time.
1563  *
1564  * bpf_prog_load_fixup_attach_type() sets expected_attach_type in @attr if
1565  * prog type requires it but has some attach types that have to be backward
1566  * compatible.
1567  */
bpf_prog_load_fixup_attach_type(union bpf_attr * attr)1568 static void bpf_prog_load_fixup_attach_type(union bpf_attr *attr)
1569 {
1570 	switch (attr->prog_type) {
1571 	case BPF_PROG_TYPE_CGROUP_SOCK:
1572 		/* Unfortunately BPF_ATTACH_TYPE_UNSPEC enumeration doesn't
1573 		 * exist so checking for non-zero is the way to go here.
1574 		 */
1575 		if (!attr->expected_attach_type)
1576 			attr->expected_attach_type =
1577 				BPF_CGROUP_INET_SOCK_CREATE;
1578 		break;
1579 	}
1580 }
1581 
1582 static int
bpf_prog_load_check_attach_type(enum bpf_prog_type prog_type,enum bpf_attach_type expected_attach_type)1583 bpf_prog_load_check_attach_type(enum bpf_prog_type prog_type,
1584 				enum bpf_attach_type expected_attach_type)
1585 {
1586 	switch (prog_type) {
1587 	case BPF_PROG_TYPE_CGROUP_SOCK:
1588 		switch (expected_attach_type) {
1589 		case BPF_CGROUP_INET_SOCK_CREATE:
1590 		case BPF_CGROUP_INET4_POST_BIND:
1591 		case BPF_CGROUP_INET6_POST_BIND:
1592 			return 0;
1593 		default:
1594 			return -EINVAL;
1595 		}
1596 	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
1597 		switch (expected_attach_type) {
1598 		case BPF_CGROUP_INET4_BIND:
1599 		case BPF_CGROUP_INET6_BIND:
1600 		case BPF_CGROUP_INET4_CONNECT:
1601 		case BPF_CGROUP_INET6_CONNECT:
1602 		case BPF_CGROUP_UDP4_SENDMSG:
1603 		case BPF_CGROUP_UDP6_SENDMSG:
1604 		case BPF_CGROUP_UDP4_RECVMSG:
1605 		case BPF_CGROUP_UDP6_RECVMSG:
1606 			return 0;
1607 		default:
1608 			return -EINVAL;
1609 		}
1610 	case BPF_PROG_TYPE_CGROUP_SKB:
1611 		switch (expected_attach_type) {
1612 		case BPF_CGROUP_INET_INGRESS:
1613 		case BPF_CGROUP_INET_EGRESS:
1614 			return 0;
1615 		default:
1616 			return -EINVAL;
1617 		}
1618 	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
1619 		switch (expected_attach_type) {
1620 		case BPF_CGROUP_SETSOCKOPT:
1621 		case BPF_CGROUP_GETSOCKOPT:
1622 			return 0;
1623 		default:
1624 			return -EINVAL;
1625 		}
1626 	default:
1627 		return 0;
1628 	}
1629 }
1630 
1631 /* last field in 'union bpf_attr' used by this command */
1632 #define	BPF_PROG_LOAD_LAST_FIELD line_info_cnt
1633 
bpf_prog_load(union bpf_attr * attr,union bpf_attr __user * uattr)1634 static int bpf_prog_load(union bpf_attr *attr, union bpf_attr __user *uattr)
1635 {
1636 	enum bpf_prog_type type = attr->prog_type;
1637 	struct bpf_prog *prog;
1638 	int err;
1639 	char license[128];
1640 	bool is_gpl;
1641 
1642 	if (CHECK_ATTR(BPF_PROG_LOAD))
1643 		return -EINVAL;
1644 
1645 	if (attr->prog_flags & ~(BPF_F_STRICT_ALIGNMENT |
1646 				 BPF_F_ANY_ALIGNMENT |
1647 				 BPF_F_TEST_STATE_FREQ |
1648 				 BPF_F_TEST_RND_HI32))
1649 		return -EINVAL;
1650 
1651 	if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) &&
1652 	    (attr->prog_flags & BPF_F_ANY_ALIGNMENT) &&
1653 	    !capable(CAP_SYS_ADMIN))
1654 		return -EPERM;
1655 
1656 	/* copy eBPF program license from user space */
1657 	if (strncpy_from_user(license, u64_to_user_ptr(attr->license),
1658 			      sizeof(license) - 1) < 0)
1659 		return -EFAULT;
1660 	license[sizeof(license) - 1] = 0;
1661 
1662 	/* eBPF programs must be GPL compatible to use GPL-ed functions */
1663 	is_gpl = license_is_gpl_compatible(license);
1664 
1665 	if (attr->insn_cnt == 0 ||
1666 	    attr->insn_cnt > (capable(CAP_SYS_ADMIN) ? BPF_COMPLEXITY_LIMIT_INSNS : BPF_MAXINSNS))
1667 		return -E2BIG;
1668 	if (type != BPF_PROG_TYPE_SOCKET_FILTER &&
1669 	    type != BPF_PROG_TYPE_CGROUP_SKB &&
1670 	    !capable(CAP_SYS_ADMIN))
1671 		return -EPERM;
1672 
1673 	bpf_prog_load_fixup_attach_type(attr);
1674 	if (bpf_prog_load_check_attach_type(type, attr->expected_attach_type))
1675 		return -EINVAL;
1676 
1677 	/* plain bpf_prog allocation */
1678 	prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER);
1679 	if (!prog)
1680 		return -ENOMEM;
1681 
1682 	prog->expected_attach_type = attr->expected_attach_type;
1683 
1684 	prog->aux->offload_requested = !!attr->prog_ifindex;
1685 
1686 	err = security_bpf_prog_alloc(prog->aux);
1687 	if (err)
1688 		goto free_prog_nouncharge;
1689 
1690 	err = bpf_prog_charge_memlock(prog);
1691 	if (err)
1692 		goto free_prog_sec;
1693 
1694 	prog->len = attr->insn_cnt;
1695 
1696 	err = -EFAULT;
1697 	if (copy_from_user(prog->insns, u64_to_user_ptr(attr->insns),
1698 			   bpf_prog_insn_size(prog)) != 0)
1699 		goto free_prog;
1700 
1701 	prog->orig_prog = NULL;
1702 	prog->jited = 0;
1703 
1704 	atomic_set(&prog->aux->refcnt, 1);
1705 	prog->gpl_compatible = is_gpl ? 1 : 0;
1706 
1707 	if (bpf_prog_is_dev_bound(prog->aux)) {
1708 		err = bpf_prog_offload_init(prog, attr);
1709 		if (err)
1710 			goto free_prog;
1711 	}
1712 
1713 	/* find program type: socket_filter vs tracing_filter */
1714 	err = find_prog_type(type, prog);
1715 	if (err < 0)
1716 		goto free_prog;
1717 
1718 	prog->aux->load_time = ktime_get_boottime_ns();
1719 	err = bpf_obj_name_cpy(prog->aux->name, attr->prog_name);
1720 	if (err)
1721 		goto free_prog;
1722 
1723 	/* run eBPF verifier */
1724 	err = bpf_check(&prog, attr, uattr);
1725 	if (err < 0)
1726 		goto free_used_maps;
1727 
1728 	prog = bpf_prog_select_runtime(prog, &err);
1729 	if (err < 0)
1730 		goto free_used_maps;
1731 
1732 	err = bpf_prog_alloc_id(prog);
1733 	if (err)
1734 		goto free_used_maps;
1735 
1736 	/* Upon success of bpf_prog_alloc_id(), the BPF prog is
1737 	 * effectively publicly exposed. However, retrieving via
1738 	 * bpf_prog_get_fd_by_id() will take another reference,
1739 	 * therefore it cannot be gone underneath us.
1740 	 *
1741 	 * Only for the time /after/ successful bpf_prog_new_fd()
1742 	 * and before returning to userspace, we might just hold
1743 	 * one reference and any parallel close on that fd could
1744 	 * rip everything out. Hence, below notifications must
1745 	 * happen before bpf_prog_new_fd().
1746 	 *
1747 	 * Also, any failure handling from this point onwards must
1748 	 * be using bpf_prog_put() given the program is exposed.
1749 	 */
1750 	bpf_prog_kallsyms_add(prog);
1751 	perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_LOAD, 0);
1752 
1753 	err = bpf_prog_new_fd(prog);
1754 	if (err < 0)
1755 		bpf_prog_put(prog);
1756 	return err;
1757 
1758 free_used_maps:
1759 	/* In case we have subprogs, we need to wait for a grace
1760 	 * period before we can tear down JIT memory since symbols
1761 	 * are already exposed under kallsyms.
1762 	 */
1763 	__bpf_prog_put_noref(prog, prog->aux->func_cnt);
1764 	return err;
1765 free_prog:
1766 	bpf_prog_uncharge_memlock(prog);
1767 free_prog_sec:
1768 	security_bpf_prog_free(prog->aux);
1769 free_prog_nouncharge:
1770 	bpf_prog_free(prog);
1771 	return err;
1772 }
1773 
1774 #define BPF_OBJ_LAST_FIELD file_flags
1775 
bpf_obj_pin(const union bpf_attr * attr)1776 static int bpf_obj_pin(const union bpf_attr *attr)
1777 {
1778 	if (CHECK_ATTR(BPF_OBJ) || attr->file_flags != 0)
1779 		return -EINVAL;
1780 
1781 	return bpf_obj_pin_user(attr->bpf_fd, u64_to_user_ptr(attr->pathname));
1782 }
1783 
bpf_obj_get(const union bpf_attr * attr)1784 static int bpf_obj_get(const union bpf_attr *attr)
1785 {
1786 	if (CHECK_ATTR(BPF_OBJ) || attr->bpf_fd != 0 ||
1787 	    attr->file_flags & ~BPF_OBJ_FLAG_MASK)
1788 		return -EINVAL;
1789 
1790 	return bpf_obj_get_user(u64_to_user_ptr(attr->pathname),
1791 				attr->file_flags);
1792 }
1793 
1794 struct bpf_raw_tracepoint {
1795 	struct bpf_raw_event_map *btp;
1796 	struct bpf_prog *prog;
1797 };
1798 
bpf_raw_tracepoint_release(struct inode * inode,struct file * filp)1799 static int bpf_raw_tracepoint_release(struct inode *inode, struct file *filp)
1800 {
1801 	struct bpf_raw_tracepoint *raw_tp = filp->private_data;
1802 
1803 	if (raw_tp->prog) {
1804 		bpf_probe_unregister(raw_tp->btp, raw_tp->prog);
1805 		bpf_prog_put(raw_tp->prog);
1806 	}
1807 	bpf_put_raw_tracepoint(raw_tp->btp);
1808 	kfree(raw_tp);
1809 	return 0;
1810 }
1811 
1812 static const struct file_operations bpf_raw_tp_fops = {
1813 	.release	= bpf_raw_tracepoint_release,
1814 	.read		= bpf_dummy_read,
1815 	.write		= bpf_dummy_write,
1816 };
1817 
1818 #define BPF_RAW_TRACEPOINT_OPEN_LAST_FIELD raw_tracepoint.prog_fd
1819 
bpf_raw_tracepoint_open(const union bpf_attr * attr)1820 static int bpf_raw_tracepoint_open(const union bpf_attr *attr)
1821 {
1822 	struct bpf_raw_tracepoint *raw_tp;
1823 	struct bpf_raw_event_map *btp;
1824 	struct bpf_prog *prog;
1825 	char tp_name[128];
1826 	int tp_fd, err;
1827 
1828 	if (strncpy_from_user(tp_name, u64_to_user_ptr(attr->raw_tracepoint.name),
1829 			      sizeof(tp_name) - 1) < 0)
1830 		return -EFAULT;
1831 	tp_name[sizeof(tp_name) - 1] = 0;
1832 
1833 	btp = bpf_get_raw_tracepoint(tp_name);
1834 	if (!btp)
1835 		return -ENOENT;
1836 
1837 	raw_tp = kzalloc(sizeof(*raw_tp), GFP_USER);
1838 	if (!raw_tp) {
1839 		err = -ENOMEM;
1840 		goto out_put_btp;
1841 	}
1842 	raw_tp->btp = btp;
1843 
1844 	prog = bpf_prog_get(attr->raw_tracepoint.prog_fd);
1845 	if (IS_ERR(prog)) {
1846 		err = PTR_ERR(prog);
1847 		goto out_free_tp;
1848 	}
1849 	if (prog->type != BPF_PROG_TYPE_RAW_TRACEPOINT &&
1850 	    prog->type != BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE) {
1851 		err = -EINVAL;
1852 		goto out_put_prog;
1853 	}
1854 
1855 	err = bpf_probe_register(raw_tp->btp, prog);
1856 	if (err)
1857 		goto out_put_prog;
1858 
1859 	raw_tp->prog = prog;
1860 	tp_fd = anon_inode_getfd("bpf-raw-tracepoint", &bpf_raw_tp_fops, raw_tp,
1861 				 O_CLOEXEC);
1862 	if (tp_fd < 0) {
1863 		bpf_probe_unregister(raw_tp->btp, prog);
1864 		err = tp_fd;
1865 		goto out_put_prog;
1866 	}
1867 	return tp_fd;
1868 
1869 out_put_prog:
1870 	bpf_prog_put(prog);
1871 out_free_tp:
1872 	kfree(raw_tp);
1873 out_put_btp:
1874 	bpf_put_raw_tracepoint(btp);
1875 	return err;
1876 }
1877 
bpf_prog_attach_check_attach_type(const struct bpf_prog * prog,enum bpf_attach_type attach_type)1878 static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog,
1879 					     enum bpf_attach_type attach_type)
1880 {
1881 	switch (prog->type) {
1882 	case BPF_PROG_TYPE_CGROUP_SOCK:
1883 	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
1884 	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
1885 		return attach_type == prog->expected_attach_type ? 0 : -EINVAL;
1886 	case BPF_PROG_TYPE_CGROUP_SKB:
1887 		return prog->enforce_expected_attach_type &&
1888 			prog->expected_attach_type != attach_type ?
1889 			-EINVAL : 0;
1890 	default:
1891 		return 0;
1892 	}
1893 }
1894 
1895 #define BPF_PROG_ATTACH_LAST_FIELD attach_flags
1896 
1897 #define BPF_F_ATTACH_MASK \
1898 	(BPF_F_ALLOW_OVERRIDE | BPF_F_ALLOW_MULTI)
1899 
bpf_prog_attach(const union bpf_attr * attr)1900 static int bpf_prog_attach(const union bpf_attr *attr)
1901 {
1902 	enum bpf_prog_type ptype;
1903 	struct bpf_prog *prog;
1904 	int ret;
1905 
1906 	if (!capable(CAP_NET_ADMIN))
1907 		return -EPERM;
1908 
1909 	if (CHECK_ATTR(BPF_PROG_ATTACH))
1910 		return -EINVAL;
1911 
1912 	if (attr->attach_flags & ~BPF_F_ATTACH_MASK)
1913 		return -EINVAL;
1914 
1915 	switch (attr->attach_type) {
1916 	case BPF_CGROUP_INET_INGRESS:
1917 	case BPF_CGROUP_INET_EGRESS:
1918 		ptype = BPF_PROG_TYPE_CGROUP_SKB;
1919 		break;
1920 	case BPF_CGROUP_INET_SOCK_CREATE:
1921 	case BPF_CGROUP_INET4_POST_BIND:
1922 	case BPF_CGROUP_INET6_POST_BIND:
1923 		ptype = BPF_PROG_TYPE_CGROUP_SOCK;
1924 		break;
1925 	case BPF_CGROUP_INET4_BIND:
1926 	case BPF_CGROUP_INET6_BIND:
1927 	case BPF_CGROUP_INET4_CONNECT:
1928 	case BPF_CGROUP_INET6_CONNECT:
1929 	case BPF_CGROUP_UDP4_SENDMSG:
1930 	case BPF_CGROUP_UDP6_SENDMSG:
1931 	case BPF_CGROUP_UDP4_RECVMSG:
1932 	case BPF_CGROUP_UDP6_RECVMSG:
1933 		ptype = BPF_PROG_TYPE_CGROUP_SOCK_ADDR;
1934 		break;
1935 	case BPF_CGROUP_SOCK_OPS:
1936 		ptype = BPF_PROG_TYPE_SOCK_OPS;
1937 		break;
1938 	case BPF_CGROUP_DEVICE:
1939 		ptype = BPF_PROG_TYPE_CGROUP_DEVICE;
1940 		break;
1941 	case BPF_SK_MSG_VERDICT:
1942 		ptype = BPF_PROG_TYPE_SK_MSG;
1943 		break;
1944 	case BPF_SK_SKB_STREAM_PARSER:
1945 	case BPF_SK_SKB_STREAM_VERDICT:
1946 		ptype = BPF_PROG_TYPE_SK_SKB;
1947 		break;
1948 	case BPF_LIRC_MODE2:
1949 		ptype = BPF_PROG_TYPE_LIRC_MODE2;
1950 		break;
1951 	case BPF_FLOW_DISSECTOR:
1952 		ptype = BPF_PROG_TYPE_FLOW_DISSECTOR;
1953 		break;
1954 	case BPF_CGROUP_SYSCTL:
1955 		ptype = BPF_PROG_TYPE_CGROUP_SYSCTL;
1956 		break;
1957 	case BPF_CGROUP_GETSOCKOPT:
1958 	case BPF_CGROUP_SETSOCKOPT:
1959 		ptype = BPF_PROG_TYPE_CGROUP_SOCKOPT;
1960 		break;
1961 	default:
1962 		return -EINVAL;
1963 	}
1964 
1965 	prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype);
1966 	if (IS_ERR(prog))
1967 		return PTR_ERR(prog);
1968 
1969 	if (bpf_prog_attach_check_attach_type(prog, attr->attach_type)) {
1970 		bpf_prog_put(prog);
1971 		return -EINVAL;
1972 	}
1973 
1974 	switch (ptype) {
1975 	case BPF_PROG_TYPE_SK_SKB:
1976 	case BPF_PROG_TYPE_SK_MSG:
1977 		ret = sock_map_get_from_fd(attr, prog);
1978 		break;
1979 	case BPF_PROG_TYPE_LIRC_MODE2:
1980 		ret = lirc_prog_attach(attr, prog);
1981 		break;
1982 	case BPF_PROG_TYPE_FLOW_DISSECTOR:
1983 		ret = skb_flow_dissector_bpf_prog_attach(attr, prog);
1984 		break;
1985 	default:
1986 		ret = cgroup_bpf_prog_attach(attr, ptype, prog);
1987 	}
1988 
1989 	if (ret)
1990 		bpf_prog_put(prog);
1991 	return ret;
1992 }
1993 
1994 #define BPF_PROG_DETACH_LAST_FIELD attach_type
1995 
bpf_prog_detach(const union bpf_attr * attr)1996 static int bpf_prog_detach(const union bpf_attr *attr)
1997 {
1998 	enum bpf_prog_type ptype;
1999 
2000 	if (!capable(CAP_NET_ADMIN))
2001 		return -EPERM;
2002 
2003 	if (CHECK_ATTR(BPF_PROG_DETACH))
2004 		return -EINVAL;
2005 
2006 	switch (attr->attach_type) {
2007 	case BPF_CGROUP_INET_INGRESS:
2008 	case BPF_CGROUP_INET_EGRESS:
2009 		ptype = BPF_PROG_TYPE_CGROUP_SKB;
2010 		break;
2011 	case BPF_CGROUP_INET_SOCK_CREATE:
2012 	case BPF_CGROUP_INET4_POST_BIND:
2013 	case BPF_CGROUP_INET6_POST_BIND:
2014 		ptype = BPF_PROG_TYPE_CGROUP_SOCK;
2015 		break;
2016 	case BPF_CGROUP_INET4_BIND:
2017 	case BPF_CGROUP_INET6_BIND:
2018 	case BPF_CGROUP_INET4_CONNECT:
2019 	case BPF_CGROUP_INET6_CONNECT:
2020 	case BPF_CGROUP_UDP4_SENDMSG:
2021 	case BPF_CGROUP_UDP6_SENDMSG:
2022 	case BPF_CGROUP_UDP4_RECVMSG:
2023 	case BPF_CGROUP_UDP6_RECVMSG:
2024 		ptype = BPF_PROG_TYPE_CGROUP_SOCK_ADDR;
2025 		break;
2026 	case BPF_CGROUP_SOCK_OPS:
2027 		ptype = BPF_PROG_TYPE_SOCK_OPS;
2028 		break;
2029 	case BPF_CGROUP_DEVICE:
2030 		ptype = BPF_PROG_TYPE_CGROUP_DEVICE;
2031 		break;
2032 	case BPF_SK_MSG_VERDICT:
2033 		return sock_map_prog_detach(attr, BPF_PROG_TYPE_SK_MSG);
2034 	case BPF_SK_SKB_STREAM_PARSER:
2035 	case BPF_SK_SKB_STREAM_VERDICT:
2036 		return sock_map_prog_detach(attr, BPF_PROG_TYPE_SK_SKB);
2037 	case BPF_LIRC_MODE2:
2038 		return lirc_prog_detach(attr);
2039 	case BPF_FLOW_DISSECTOR:
2040 		return skb_flow_dissector_bpf_prog_detach(attr);
2041 	case BPF_CGROUP_SYSCTL:
2042 		ptype = BPF_PROG_TYPE_CGROUP_SYSCTL;
2043 		break;
2044 	case BPF_CGROUP_GETSOCKOPT:
2045 	case BPF_CGROUP_SETSOCKOPT:
2046 		ptype = BPF_PROG_TYPE_CGROUP_SOCKOPT;
2047 		break;
2048 	default:
2049 		return -EINVAL;
2050 	}
2051 
2052 	return cgroup_bpf_prog_detach(attr, ptype);
2053 }
2054 
2055 #define BPF_PROG_QUERY_LAST_FIELD query.prog_cnt
2056 
bpf_prog_query(const union bpf_attr * attr,union bpf_attr __user * uattr)2057 static int bpf_prog_query(const union bpf_attr *attr,
2058 			  union bpf_attr __user *uattr)
2059 {
2060 	if (!capable(CAP_NET_ADMIN))
2061 		return -EPERM;
2062 	if (CHECK_ATTR(BPF_PROG_QUERY))
2063 		return -EINVAL;
2064 	if (attr->query.query_flags & ~BPF_F_QUERY_EFFECTIVE)
2065 		return -EINVAL;
2066 
2067 	switch (attr->query.attach_type) {
2068 	case BPF_CGROUP_INET_INGRESS:
2069 	case BPF_CGROUP_INET_EGRESS:
2070 	case BPF_CGROUP_INET_SOCK_CREATE:
2071 	case BPF_CGROUP_INET4_BIND:
2072 	case BPF_CGROUP_INET6_BIND:
2073 	case BPF_CGROUP_INET4_POST_BIND:
2074 	case BPF_CGROUP_INET6_POST_BIND:
2075 	case BPF_CGROUP_INET4_CONNECT:
2076 	case BPF_CGROUP_INET6_CONNECT:
2077 	case BPF_CGROUP_UDP4_SENDMSG:
2078 	case BPF_CGROUP_UDP6_SENDMSG:
2079 	case BPF_CGROUP_UDP4_RECVMSG:
2080 	case BPF_CGROUP_UDP6_RECVMSG:
2081 	case BPF_CGROUP_SOCK_OPS:
2082 	case BPF_CGROUP_DEVICE:
2083 	case BPF_CGROUP_SYSCTL:
2084 	case BPF_CGROUP_GETSOCKOPT:
2085 	case BPF_CGROUP_SETSOCKOPT:
2086 		break;
2087 	case BPF_LIRC_MODE2:
2088 		return lirc_prog_query(attr, uattr);
2089 	case BPF_FLOW_DISSECTOR:
2090 		return skb_flow_dissector_prog_query(attr, uattr);
2091 	default:
2092 		return -EINVAL;
2093 	}
2094 
2095 	return cgroup_bpf_prog_query(attr, uattr);
2096 }
2097 
2098 #define BPF_PROG_TEST_RUN_LAST_FIELD test.ctx_out
2099 
bpf_prog_test_run(const union bpf_attr * attr,union bpf_attr __user * uattr)2100 static int bpf_prog_test_run(const union bpf_attr *attr,
2101 			     union bpf_attr __user *uattr)
2102 {
2103 	struct bpf_prog *prog;
2104 	int ret = -ENOTSUPP;
2105 
2106 	if (!capable(CAP_SYS_ADMIN))
2107 		return -EPERM;
2108 	if (CHECK_ATTR(BPF_PROG_TEST_RUN))
2109 		return -EINVAL;
2110 
2111 	if ((attr->test.ctx_size_in && !attr->test.ctx_in) ||
2112 	    (!attr->test.ctx_size_in && attr->test.ctx_in))
2113 		return -EINVAL;
2114 
2115 	if ((attr->test.ctx_size_out && !attr->test.ctx_out) ||
2116 	    (!attr->test.ctx_size_out && attr->test.ctx_out))
2117 		return -EINVAL;
2118 
2119 	prog = bpf_prog_get(attr->test.prog_fd);
2120 	if (IS_ERR(prog))
2121 		return PTR_ERR(prog);
2122 
2123 	if (prog->aux->ops->test_run)
2124 		ret = prog->aux->ops->test_run(prog, attr, uattr);
2125 
2126 	bpf_prog_put(prog);
2127 	return ret;
2128 }
2129 
2130 #define BPF_OBJ_GET_NEXT_ID_LAST_FIELD next_id
2131 
bpf_obj_get_next_id(const union bpf_attr * attr,union bpf_attr __user * uattr,struct idr * idr,spinlock_t * lock)2132 static int bpf_obj_get_next_id(const union bpf_attr *attr,
2133 			       union bpf_attr __user *uattr,
2134 			       struct idr *idr,
2135 			       spinlock_t *lock)
2136 {
2137 	u32 next_id = attr->start_id;
2138 	int err = 0;
2139 
2140 	if (CHECK_ATTR(BPF_OBJ_GET_NEXT_ID) || next_id >= INT_MAX)
2141 		return -EINVAL;
2142 
2143 	if (!capable(CAP_SYS_ADMIN))
2144 		return -EPERM;
2145 
2146 	next_id++;
2147 	spin_lock_bh(lock);
2148 	if (!idr_get_next(idr, &next_id))
2149 		err = -ENOENT;
2150 	spin_unlock_bh(lock);
2151 
2152 	if (!err)
2153 		err = put_user(next_id, &uattr->next_id);
2154 
2155 	return err;
2156 }
2157 
2158 #define BPF_PROG_GET_FD_BY_ID_LAST_FIELD prog_id
2159 
bpf_prog_get_fd_by_id(const union bpf_attr * attr)2160 static int bpf_prog_get_fd_by_id(const union bpf_attr *attr)
2161 {
2162 	struct bpf_prog *prog;
2163 	u32 id = attr->prog_id;
2164 	int fd;
2165 
2166 	if (CHECK_ATTR(BPF_PROG_GET_FD_BY_ID))
2167 		return -EINVAL;
2168 
2169 	if (!capable(CAP_SYS_ADMIN))
2170 		return -EPERM;
2171 
2172 	spin_lock_bh(&prog_idr_lock);
2173 	prog = idr_find(&prog_idr, id);
2174 	if (prog)
2175 		prog = bpf_prog_inc_not_zero(prog);
2176 	else
2177 		prog = ERR_PTR(-ENOENT);
2178 	spin_unlock_bh(&prog_idr_lock);
2179 
2180 	if (IS_ERR(prog))
2181 		return PTR_ERR(prog);
2182 
2183 	fd = bpf_prog_new_fd(prog);
2184 	if (fd < 0)
2185 		bpf_prog_put(prog);
2186 
2187 	return fd;
2188 }
2189 
2190 #define BPF_MAP_GET_FD_BY_ID_LAST_FIELD open_flags
2191 
bpf_map_get_fd_by_id(const union bpf_attr * attr)2192 static int bpf_map_get_fd_by_id(const union bpf_attr *attr)
2193 {
2194 	struct bpf_map *map;
2195 	u32 id = attr->map_id;
2196 	int f_flags;
2197 	int fd;
2198 
2199 	if (CHECK_ATTR(BPF_MAP_GET_FD_BY_ID) ||
2200 	    attr->open_flags & ~BPF_OBJ_FLAG_MASK)
2201 		return -EINVAL;
2202 
2203 	if (!capable(CAP_SYS_ADMIN))
2204 		return -EPERM;
2205 
2206 	f_flags = bpf_get_file_flag(attr->open_flags);
2207 	if (f_flags < 0)
2208 		return f_flags;
2209 
2210 	spin_lock_bh(&map_idr_lock);
2211 	map = idr_find(&map_idr, id);
2212 	if (map)
2213 		map = __bpf_map_inc_not_zero(map, true);
2214 	else
2215 		map = ERR_PTR(-ENOENT);
2216 	spin_unlock_bh(&map_idr_lock);
2217 
2218 	if (IS_ERR(map))
2219 		return PTR_ERR(map);
2220 
2221 	fd = bpf_map_new_fd(map, f_flags);
2222 	if (fd < 0)
2223 		bpf_map_put_with_uref(map);
2224 
2225 	return fd;
2226 }
2227 
bpf_map_from_imm(const struct bpf_prog * prog,unsigned long addr,u32 * off,u32 * type)2228 static const struct bpf_map *bpf_map_from_imm(const struct bpf_prog *prog,
2229 					      unsigned long addr, u32 *off,
2230 					      u32 *type)
2231 {
2232 	const struct bpf_map *map;
2233 	int i;
2234 
2235 	for (i = 0, *off = 0; i < prog->aux->used_map_cnt; i++) {
2236 		map = prog->aux->used_maps[i];
2237 		if (map == (void *)addr) {
2238 			*type = BPF_PSEUDO_MAP_FD;
2239 			return map;
2240 		}
2241 		if (!map->ops->map_direct_value_meta)
2242 			continue;
2243 		if (!map->ops->map_direct_value_meta(map, addr, off)) {
2244 			*type = BPF_PSEUDO_MAP_VALUE;
2245 			return map;
2246 		}
2247 	}
2248 
2249 	return NULL;
2250 }
2251 
bpf_insn_prepare_dump(const struct bpf_prog * prog,const struct cred * f_cred)2252 static struct bpf_insn *bpf_insn_prepare_dump(const struct bpf_prog *prog,
2253 					      const struct cred *f_cred)
2254 {
2255 	const struct bpf_map *map;
2256 	struct bpf_insn *insns;
2257 	u32 off, type;
2258 	u64 imm;
2259 	int i;
2260 
2261 	insns = kmemdup(prog->insnsi, bpf_prog_insn_size(prog),
2262 			GFP_USER);
2263 	if (!insns)
2264 		return insns;
2265 
2266 	for (i = 0; i < prog->len; i++) {
2267 		if (insns[i].code == (BPF_JMP | BPF_TAIL_CALL)) {
2268 			insns[i].code = BPF_JMP | BPF_CALL;
2269 			insns[i].imm = BPF_FUNC_tail_call;
2270 			/* fall-through */
2271 		}
2272 		if (insns[i].code == (BPF_JMP | BPF_CALL) ||
2273 		    insns[i].code == (BPF_JMP | BPF_CALL_ARGS)) {
2274 			if (insns[i].code == (BPF_JMP | BPF_CALL_ARGS))
2275 				insns[i].code = BPF_JMP | BPF_CALL;
2276 			if (!bpf_dump_raw_ok(f_cred))
2277 				insns[i].imm = 0;
2278 			continue;
2279 		}
2280 
2281 		if (insns[i].code != (BPF_LD | BPF_IMM | BPF_DW))
2282 			continue;
2283 
2284 		imm = ((u64)insns[i + 1].imm << 32) | (u32)insns[i].imm;
2285 		map = bpf_map_from_imm(prog, imm, &off, &type);
2286 		if (map) {
2287 			insns[i].src_reg = type;
2288 			insns[i].imm = map->id;
2289 			insns[i + 1].imm = off;
2290 			continue;
2291 		}
2292 	}
2293 
2294 	return insns;
2295 }
2296 
set_info_rec_size(struct bpf_prog_info * info)2297 static int set_info_rec_size(struct bpf_prog_info *info)
2298 {
2299 	/*
2300 	 * Ensure info.*_rec_size is the same as kernel expected size
2301 	 *
2302 	 * or
2303 	 *
2304 	 * Only allow zero *_rec_size if both _rec_size and _cnt are
2305 	 * zero.  In this case, the kernel will set the expected
2306 	 * _rec_size back to the info.
2307 	 */
2308 
2309 	if ((info->nr_func_info || info->func_info_rec_size) &&
2310 	    info->func_info_rec_size != sizeof(struct bpf_func_info))
2311 		return -EINVAL;
2312 
2313 	if ((info->nr_line_info || info->line_info_rec_size) &&
2314 	    info->line_info_rec_size != sizeof(struct bpf_line_info))
2315 		return -EINVAL;
2316 
2317 	if ((info->nr_jited_line_info || info->jited_line_info_rec_size) &&
2318 	    info->jited_line_info_rec_size != sizeof(__u64))
2319 		return -EINVAL;
2320 
2321 	info->func_info_rec_size = sizeof(struct bpf_func_info);
2322 	info->line_info_rec_size = sizeof(struct bpf_line_info);
2323 	info->jited_line_info_rec_size = sizeof(__u64);
2324 
2325 	return 0;
2326 }
2327 
bpf_prog_get_info_by_fd(struct file * file,struct bpf_prog * prog,const union bpf_attr * attr,union bpf_attr __user * uattr)2328 static int bpf_prog_get_info_by_fd(struct file *file,
2329 				   struct bpf_prog *prog,
2330 				   const union bpf_attr *attr,
2331 				   union bpf_attr __user *uattr)
2332 {
2333 	struct bpf_prog_info __user *uinfo = u64_to_user_ptr(attr->info.info);
2334 	struct bpf_prog_info info;
2335 	u32 info_len = attr->info.info_len;
2336 	struct bpf_prog_stats stats;
2337 	char __user *uinsns;
2338 	u32 ulen;
2339 	int err;
2340 
2341 	err = bpf_check_uarg_tail_zero(uinfo, sizeof(info), info_len);
2342 	if (err)
2343 		return err;
2344 	info_len = min_t(u32, sizeof(info), info_len);
2345 
2346 	memset(&info, 0, sizeof(info));
2347 	if (copy_from_user(&info, uinfo, info_len))
2348 		return -EFAULT;
2349 
2350 	info.type = prog->type;
2351 	info.id = prog->aux->id;
2352 	info.load_time = prog->aux->load_time;
2353 	info.created_by_uid = from_kuid_munged(current_user_ns(),
2354 					       prog->aux->user->uid);
2355 	info.gpl_compatible = prog->gpl_compatible;
2356 
2357 	memcpy(info.tag, prog->tag, sizeof(prog->tag));
2358 	memcpy(info.name, prog->aux->name, sizeof(prog->aux->name));
2359 
2360 	ulen = info.nr_map_ids;
2361 	info.nr_map_ids = prog->aux->used_map_cnt;
2362 	ulen = min_t(u32, info.nr_map_ids, ulen);
2363 	if (ulen) {
2364 		u32 __user *user_map_ids = u64_to_user_ptr(info.map_ids);
2365 		u32 i;
2366 
2367 		for (i = 0; i < ulen; i++)
2368 			if (put_user(prog->aux->used_maps[i]->id,
2369 				     &user_map_ids[i]))
2370 				return -EFAULT;
2371 	}
2372 
2373 	err = set_info_rec_size(&info);
2374 	if (err)
2375 		return err;
2376 
2377 	bpf_prog_get_stats(prog, &stats);
2378 	info.run_time_ns = stats.nsecs;
2379 	info.run_cnt = stats.cnt;
2380 
2381 	if (!capable(CAP_SYS_ADMIN)) {
2382 		info.jited_prog_len = 0;
2383 		info.xlated_prog_len = 0;
2384 		info.nr_jited_ksyms = 0;
2385 		info.nr_jited_func_lens = 0;
2386 		info.nr_func_info = 0;
2387 		info.nr_line_info = 0;
2388 		info.nr_jited_line_info = 0;
2389 		goto done;
2390 	}
2391 
2392 	ulen = info.xlated_prog_len;
2393 	info.xlated_prog_len = bpf_prog_insn_size(prog);
2394 	if (info.xlated_prog_len && ulen) {
2395 		struct bpf_insn *insns_sanitized;
2396 		bool fault;
2397 
2398 		if (prog->blinded && !bpf_dump_raw_ok(file->f_cred)) {
2399 			info.xlated_prog_insns = 0;
2400 			goto done;
2401 		}
2402 		insns_sanitized = bpf_insn_prepare_dump(prog, file->f_cred);
2403 		if (!insns_sanitized)
2404 			return -ENOMEM;
2405 		uinsns = u64_to_user_ptr(info.xlated_prog_insns);
2406 		ulen = min_t(u32, info.xlated_prog_len, ulen);
2407 		fault = copy_to_user(uinsns, insns_sanitized, ulen);
2408 		kfree(insns_sanitized);
2409 		if (fault)
2410 			return -EFAULT;
2411 	}
2412 
2413 	if (bpf_prog_is_dev_bound(prog->aux)) {
2414 		err = bpf_prog_offload_info_fill(&info, prog);
2415 		if (err)
2416 			return err;
2417 		goto done;
2418 	}
2419 
2420 	/* NOTE: the following code is supposed to be skipped for offload.
2421 	 * bpf_prog_offload_info_fill() is the place to fill similar fields
2422 	 * for offload.
2423 	 */
2424 	ulen = info.jited_prog_len;
2425 	if (prog->aux->func_cnt) {
2426 		u32 i;
2427 
2428 		info.jited_prog_len = 0;
2429 		for (i = 0; i < prog->aux->func_cnt; i++)
2430 			info.jited_prog_len += prog->aux->func[i]->jited_len;
2431 	} else {
2432 		info.jited_prog_len = prog->jited_len;
2433 	}
2434 
2435 	if (info.jited_prog_len && ulen) {
2436 		if (bpf_dump_raw_ok(file->f_cred)) {
2437 			uinsns = u64_to_user_ptr(info.jited_prog_insns);
2438 			ulen = min_t(u32, info.jited_prog_len, ulen);
2439 
2440 			/* for multi-function programs, copy the JITed
2441 			 * instructions for all the functions
2442 			 */
2443 			if (prog->aux->func_cnt) {
2444 				u32 len, free, i;
2445 				u8 *img;
2446 
2447 				free = ulen;
2448 				for (i = 0; i < prog->aux->func_cnt; i++) {
2449 					len = prog->aux->func[i]->jited_len;
2450 					len = min_t(u32, len, free);
2451 					img = (u8 *) prog->aux->func[i]->bpf_func;
2452 					if (copy_to_user(uinsns, img, len))
2453 						return -EFAULT;
2454 					uinsns += len;
2455 					free -= len;
2456 					if (!free)
2457 						break;
2458 				}
2459 			} else {
2460 				if (copy_to_user(uinsns, prog->bpf_func, ulen))
2461 					return -EFAULT;
2462 			}
2463 		} else {
2464 			info.jited_prog_insns = 0;
2465 		}
2466 	}
2467 
2468 	ulen = info.nr_jited_ksyms;
2469 	info.nr_jited_ksyms = prog->aux->func_cnt ? : 1;
2470 	if (ulen) {
2471 		if (bpf_dump_raw_ok(file->f_cred)) {
2472 			unsigned long ksym_addr;
2473 			u64 __user *user_ksyms;
2474 			u32 i;
2475 
2476 			/* copy the address of the kernel symbol
2477 			 * corresponding to each function
2478 			 */
2479 			ulen = min_t(u32, info.nr_jited_ksyms, ulen);
2480 			user_ksyms = u64_to_user_ptr(info.jited_ksyms);
2481 			if (prog->aux->func_cnt) {
2482 				for (i = 0; i < ulen; i++) {
2483 					ksym_addr = (unsigned long)
2484 						prog->aux->func[i]->bpf_func;
2485 					if (put_user((u64) ksym_addr,
2486 						     &user_ksyms[i]))
2487 						return -EFAULT;
2488 				}
2489 			} else {
2490 				ksym_addr = (unsigned long) prog->bpf_func;
2491 				if (put_user((u64) ksym_addr, &user_ksyms[0]))
2492 					return -EFAULT;
2493 			}
2494 		} else {
2495 			info.jited_ksyms = 0;
2496 		}
2497 	}
2498 
2499 	ulen = info.nr_jited_func_lens;
2500 	info.nr_jited_func_lens = prog->aux->func_cnt ? : 1;
2501 	if (ulen) {
2502 		if (bpf_dump_raw_ok(file->f_cred)) {
2503 			u32 __user *user_lens;
2504 			u32 func_len, i;
2505 
2506 			/* copy the JITed image lengths for each function */
2507 			ulen = min_t(u32, info.nr_jited_func_lens, ulen);
2508 			user_lens = u64_to_user_ptr(info.jited_func_lens);
2509 			if (prog->aux->func_cnt) {
2510 				for (i = 0; i < ulen; i++) {
2511 					func_len =
2512 						prog->aux->func[i]->jited_len;
2513 					if (put_user(func_len, &user_lens[i]))
2514 						return -EFAULT;
2515 				}
2516 			} else {
2517 				func_len = prog->jited_len;
2518 				if (put_user(func_len, &user_lens[0]))
2519 					return -EFAULT;
2520 			}
2521 		} else {
2522 			info.jited_func_lens = 0;
2523 		}
2524 	}
2525 
2526 	if (prog->aux->btf)
2527 		info.btf_id = btf_id(prog->aux->btf);
2528 
2529 	ulen = info.nr_func_info;
2530 	info.nr_func_info = prog->aux->func_info_cnt;
2531 	if (info.nr_func_info && ulen) {
2532 		char __user *user_finfo;
2533 
2534 		user_finfo = u64_to_user_ptr(info.func_info);
2535 		ulen = min_t(u32, info.nr_func_info, ulen);
2536 		if (copy_to_user(user_finfo, prog->aux->func_info,
2537 				 info.func_info_rec_size * ulen))
2538 			return -EFAULT;
2539 	}
2540 
2541 	ulen = info.nr_line_info;
2542 	info.nr_line_info = prog->aux->nr_linfo;
2543 	if (info.nr_line_info && ulen) {
2544 		__u8 __user *user_linfo;
2545 
2546 		user_linfo = u64_to_user_ptr(info.line_info);
2547 		ulen = min_t(u32, info.nr_line_info, ulen);
2548 		if (copy_to_user(user_linfo, prog->aux->linfo,
2549 				 info.line_info_rec_size * ulen))
2550 			return -EFAULT;
2551 	}
2552 
2553 	ulen = info.nr_jited_line_info;
2554 	if (prog->aux->jited_linfo)
2555 		info.nr_jited_line_info = prog->aux->nr_linfo;
2556 	else
2557 		info.nr_jited_line_info = 0;
2558 	if (info.nr_jited_line_info && ulen) {
2559 		if (bpf_dump_raw_ok(file->f_cred)) {
2560 			__u64 __user *user_linfo;
2561 			u32 i;
2562 
2563 			user_linfo = u64_to_user_ptr(info.jited_line_info);
2564 			ulen = min_t(u32, info.nr_jited_line_info, ulen);
2565 			for (i = 0; i < ulen; i++) {
2566 				if (put_user((__u64)(long)prog->aux->jited_linfo[i],
2567 					     &user_linfo[i]))
2568 					return -EFAULT;
2569 			}
2570 		} else {
2571 			info.jited_line_info = 0;
2572 		}
2573 	}
2574 
2575 	ulen = info.nr_prog_tags;
2576 	info.nr_prog_tags = prog->aux->func_cnt ? : 1;
2577 	if (ulen) {
2578 		__u8 __user (*user_prog_tags)[BPF_TAG_SIZE];
2579 		u32 i;
2580 
2581 		user_prog_tags = u64_to_user_ptr(info.prog_tags);
2582 		ulen = min_t(u32, info.nr_prog_tags, ulen);
2583 		if (prog->aux->func_cnt) {
2584 			for (i = 0; i < ulen; i++) {
2585 				if (copy_to_user(user_prog_tags[i],
2586 						 prog->aux->func[i]->tag,
2587 						 BPF_TAG_SIZE))
2588 					return -EFAULT;
2589 			}
2590 		} else {
2591 			if (copy_to_user(user_prog_tags[0],
2592 					 prog->tag, BPF_TAG_SIZE))
2593 				return -EFAULT;
2594 		}
2595 	}
2596 
2597 done:
2598 	if (copy_to_user(uinfo, &info, info_len) ||
2599 	    put_user(info_len, &uattr->info.info_len))
2600 		return -EFAULT;
2601 
2602 	return 0;
2603 }
2604 
bpf_map_get_info_by_fd(struct file * file,struct bpf_map * map,const union bpf_attr * attr,union bpf_attr __user * uattr)2605 static int bpf_map_get_info_by_fd(struct file *file,
2606 				  struct bpf_map *map,
2607 				  const union bpf_attr *attr,
2608 				  union bpf_attr __user *uattr)
2609 {
2610 	struct bpf_map_info __user *uinfo = u64_to_user_ptr(attr->info.info);
2611 	struct bpf_map_info info;
2612 	u32 info_len = attr->info.info_len;
2613 	int err;
2614 
2615 	err = bpf_check_uarg_tail_zero(uinfo, sizeof(info), info_len);
2616 	if (err)
2617 		return err;
2618 	info_len = min_t(u32, sizeof(info), info_len);
2619 
2620 	memset(&info, 0, sizeof(info));
2621 	info.type = map->map_type;
2622 	info.id = map->id;
2623 	info.key_size = map->key_size;
2624 	info.value_size = map->value_size;
2625 	info.max_entries = map->max_entries;
2626 	info.map_flags = map->map_flags;
2627 	memcpy(info.name, map->name, sizeof(map->name));
2628 
2629 	if (map->btf) {
2630 		info.btf_id = btf_id(map->btf);
2631 		info.btf_key_type_id = map->btf_key_type_id;
2632 		info.btf_value_type_id = map->btf_value_type_id;
2633 	}
2634 
2635 	if (bpf_map_is_dev_bound(map)) {
2636 		err = bpf_map_offload_info_fill(&info, map);
2637 		if (err)
2638 			return err;
2639 	}
2640 
2641 	if (copy_to_user(uinfo, &info, info_len) ||
2642 	    put_user(info_len, &uattr->info.info_len))
2643 		return -EFAULT;
2644 
2645 	return 0;
2646 }
2647 
bpf_btf_get_info_by_fd(struct file * file,struct btf * btf,const union bpf_attr * attr,union bpf_attr __user * uattr)2648 static int bpf_btf_get_info_by_fd(struct file *file,
2649 				  struct btf *btf,
2650 				  const union bpf_attr *attr,
2651 				  union bpf_attr __user *uattr)
2652 {
2653 	struct bpf_btf_info __user *uinfo = u64_to_user_ptr(attr->info.info);
2654 	u32 info_len = attr->info.info_len;
2655 	int err;
2656 
2657 	err = bpf_check_uarg_tail_zero(uinfo, sizeof(*uinfo), info_len);
2658 	if (err)
2659 		return err;
2660 
2661 	return btf_get_info_by_fd(btf, attr, uattr);
2662 }
2663 
2664 #define BPF_OBJ_GET_INFO_BY_FD_LAST_FIELD info.info
2665 
bpf_obj_get_info_by_fd(const union bpf_attr * attr,union bpf_attr __user * uattr)2666 static int bpf_obj_get_info_by_fd(const union bpf_attr *attr,
2667 				  union bpf_attr __user *uattr)
2668 {
2669 	int ufd = attr->info.bpf_fd;
2670 	struct fd f;
2671 	int err;
2672 
2673 	if (CHECK_ATTR(BPF_OBJ_GET_INFO_BY_FD))
2674 		return -EINVAL;
2675 
2676 	f = fdget(ufd);
2677 	if (!f.file)
2678 		return -EBADFD;
2679 
2680 	if (f.file->f_op == &bpf_prog_fops)
2681 		err = bpf_prog_get_info_by_fd(f.file, f.file->private_data, attr,
2682 					      uattr);
2683 	else if (f.file->f_op == &bpf_map_fops)
2684 		err = bpf_map_get_info_by_fd(f.file, f.file->private_data, attr,
2685 					     uattr);
2686 	else if (f.file->f_op == &btf_fops)
2687 		err = bpf_btf_get_info_by_fd(f.file, f.file->private_data, attr, uattr);
2688 	else
2689 		err = -EINVAL;
2690 
2691 	fdput(f);
2692 	return err;
2693 }
2694 
2695 #define BPF_BTF_LOAD_LAST_FIELD btf_log_level
2696 
bpf_btf_load(const union bpf_attr * attr)2697 static int bpf_btf_load(const union bpf_attr *attr)
2698 {
2699 	if (CHECK_ATTR(BPF_BTF_LOAD))
2700 		return -EINVAL;
2701 
2702 	if (!capable(CAP_SYS_ADMIN))
2703 		return -EPERM;
2704 
2705 	return btf_new_fd(attr);
2706 }
2707 
2708 #define BPF_BTF_GET_FD_BY_ID_LAST_FIELD btf_id
2709 
bpf_btf_get_fd_by_id(const union bpf_attr * attr)2710 static int bpf_btf_get_fd_by_id(const union bpf_attr *attr)
2711 {
2712 	if (CHECK_ATTR(BPF_BTF_GET_FD_BY_ID))
2713 		return -EINVAL;
2714 
2715 	if (!capable(CAP_SYS_ADMIN))
2716 		return -EPERM;
2717 
2718 	return btf_get_fd_by_id(attr->btf_id);
2719 }
2720 
bpf_task_fd_query_copy(const union bpf_attr * attr,union bpf_attr __user * uattr,u32 prog_id,u32 fd_type,const char * buf,u64 probe_offset,u64 probe_addr)2721 static int bpf_task_fd_query_copy(const union bpf_attr *attr,
2722 				    union bpf_attr __user *uattr,
2723 				    u32 prog_id, u32 fd_type,
2724 				    const char *buf, u64 probe_offset,
2725 				    u64 probe_addr)
2726 {
2727 	char __user *ubuf = u64_to_user_ptr(attr->task_fd_query.buf);
2728 	u32 len = buf ? strlen(buf) : 0, input_len;
2729 	int err = 0;
2730 
2731 	if (put_user(len, &uattr->task_fd_query.buf_len))
2732 		return -EFAULT;
2733 	input_len = attr->task_fd_query.buf_len;
2734 	if (input_len && ubuf) {
2735 		if (!len) {
2736 			/* nothing to copy, just make ubuf NULL terminated */
2737 			char zero = '\0';
2738 
2739 			if (put_user(zero, ubuf))
2740 				return -EFAULT;
2741 		} else if (input_len >= len + 1) {
2742 			/* ubuf can hold the string with NULL terminator */
2743 			if (copy_to_user(ubuf, buf, len + 1))
2744 				return -EFAULT;
2745 		} else {
2746 			/* ubuf cannot hold the string with NULL terminator,
2747 			 * do a partial copy with NULL terminator.
2748 			 */
2749 			char zero = '\0';
2750 
2751 			err = -ENOSPC;
2752 			if (copy_to_user(ubuf, buf, input_len - 1))
2753 				return -EFAULT;
2754 			if (put_user(zero, ubuf + input_len - 1))
2755 				return -EFAULT;
2756 		}
2757 	}
2758 
2759 	if (put_user(prog_id, &uattr->task_fd_query.prog_id) ||
2760 	    put_user(fd_type, &uattr->task_fd_query.fd_type) ||
2761 	    put_user(probe_offset, &uattr->task_fd_query.probe_offset) ||
2762 	    put_user(probe_addr, &uattr->task_fd_query.probe_addr))
2763 		return -EFAULT;
2764 
2765 	return err;
2766 }
2767 
2768 #define BPF_TASK_FD_QUERY_LAST_FIELD task_fd_query.probe_addr
2769 
bpf_task_fd_query(const union bpf_attr * attr,union bpf_attr __user * uattr)2770 static int bpf_task_fd_query(const union bpf_attr *attr,
2771 			     union bpf_attr __user *uattr)
2772 {
2773 	pid_t pid = attr->task_fd_query.pid;
2774 	u32 fd = attr->task_fd_query.fd;
2775 	const struct perf_event *event;
2776 	struct files_struct *files;
2777 	struct task_struct *task;
2778 	struct file *file;
2779 	int err;
2780 
2781 	if (CHECK_ATTR(BPF_TASK_FD_QUERY))
2782 		return -EINVAL;
2783 
2784 	if (!capable(CAP_SYS_ADMIN))
2785 		return -EPERM;
2786 
2787 	if (attr->task_fd_query.flags != 0)
2788 		return -EINVAL;
2789 
2790 	rcu_read_lock();
2791 	task = get_pid_task(find_vpid(pid), PIDTYPE_PID);
2792 	rcu_read_unlock();
2793 	if (!task)
2794 		return -ENOENT;
2795 
2796 	files = get_files_struct(task);
2797 	put_task_struct(task);
2798 	if (!files)
2799 		return -ENOENT;
2800 
2801 	err = 0;
2802 	spin_lock(&files->file_lock);
2803 	file = fcheck_files(files, fd);
2804 	if (!file)
2805 		err = -EBADF;
2806 	else
2807 		get_file(file);
2808 	spin_unlock(&files->file_lock);
2809 	put_files_struct(files);
2810 
2811 	if (err)
2812 		goto out;
2813 
2814 	if (file->f_op == &bpf_raw_tp_fops) {
2815 		struct bpf_raw_tracepoint *raw_tp = file->private_data;
2816 		struct bpf_raw_event_map *btp = raw_tp->btp;
2817 
2818 		err = bpf_task_fd_query_copy(attr, uattr,
2819 					     raw_tp->prog->aux->id,
2820 					     BPF_FD_TYPE_RAW_TRACEPOINT,
2821 					     btp->tp->name, 0, 0);
2822 		goto put_file;
2823 	}
2824 
2825 	event = perf_get_event(file);
2826 	if (!IS_ERR(event)) {
2827 		u64 probe_offset, probe_addr;
2828 		u32 prog_id, fd_type;
2829 		const char *buf;
2830 
2831 		err = bpf_get_perf_event_info(event, &prog_id, &fd_type,
2832 					      &buf, &probe_offset,
2833 					      &probe_addr);
2834 		if (!err)
2835 			err = bpf_task_fd_query_copy(attr, uattr, prog_id,
2836 						     fd_type, buf,
2837 						     probe_offset,
2838 						     probe_addr);
2839 		goto put_file;
2840 	}
2841 
2842 	err = -ENOTSUPP;
2843 put_file:
2844 	fput(file);
2845 out:
2846 	return err;
2847 }
2848 
SYSCALL_DEFINE3(bpf,int,cmd,union bpf_attr __user *,uattr,unsigned int,size)2849 SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size)
2850 {
2851 	union bpf_attr attr;
2852 	int err;
2853 
2854 	if (sysctl_unprivileged_bpf_disabled && !capable(CAP_SYS_ADMIN))
2855 		return -EPERM;
2856 
2857 	err = bpf_check_uarg_tail_zero(uattr, sizeof(attr), size);
2858 	if (err)
2859 		return err;
2860 	size = min_t(u32, size, sizeof(attr));
2861 
2862 	/* copy attributes from user space, may be less than sizeof(bpf_attr) */
2863 	memset(&attr, 0, sizeof(attr));
2864 	if (copy_from_user(&attr, uattr, size) != 0)
2865 		return -EFAULT;
2866 
2867 	err = security_bpf(cmd, &attr, size);
2868 	if (err < 0)
2869 		return err;
2870 
2871 	switch (cmd) {
2872 	case BPF_MAP_CREATE:
2873 		err = map_create(&attr);
2874 		break;
2875 	case BPF_MAP_LOOKUP_ELEM:
2876 		err = map_lookup_elem(&attr);
2877 		break;
2878 	case BPF_MAP_UPDATE_ELEM:
2879 		err = map_update_elem(&attr);
2880 		break;
2881 	case BPF_MAP_DELETE_ELEM:
2882 		err = map_delete_elem(&attr);
2883 		break;
2884 	case BPF_MAP_GET_NEXT_KEY:
2885 		err = map_get_next_key(&attr);
2886 		break;
2887 	case BPF_MAP_FREEZE:
2888 		err = map_freeze(&attr);
2889 		break;
2890 	case BPF_PROG_LOAD:
2891 		err = bpf_prog_load(&attr, uattr);
2892 		break;
2893 	case BPF_OBJ_PIN:
2894 		err = bpf_obj_pin(&attr);
2895 		break;
2896 	case BPF_OBJ_GET:
2897 		err = bpf_obj_get(&attr);
2898 		break;
2899 	case BPF_PROG_ATTACH:
2900 		err = bpf_prog_attach(&attr);
2901 		break;
2902 	case BPF_PROG_DETACH:
2903 		err = bpf_prog_detach(&attr);
2904 		break;
2905 	case BPF_PROG_QUERY:
2906 		err = bpf_prog_query(&attr, uattr);
2907 		break;
2908 	case BPF_PROG_TEST_RUN:
2909 		err = bpf_prog_test_run(&attr, uattr);
2910 		break;
2911 	case BPF_PROG_GET_NEXT_ID:
2912 		err = bpf_obj_get_next_id(&attr, uattr,
2913 					  &prog_idr, &prog_idr_lock);
2914 		break;
2915 	case BPF_MAP_GET_NEXT_ID:
2916 		err = bpf_obj_get_next_id(&attr, uattr,
2917 					  &map_idr, &map_idr_lock);
2918 		break;
2919 	case BPF_BTF_GET_NEXT_ID:
2920 		err = bpf_obj_get_next_id(&attr, uattr,
2921 					  &btf_idr, &btf_idr_lock);
2922 		break;
2923 	case BPF_PROG_GET_FD_BY_ID:
2924 		err = bpf_prog_get_fd_by_id(&attr);
2925 		break;
2926 	case BPF_MAP_GET_FD_BY_ID:
2927 		err = bpf_map_get_fd_by_id(&attr);
2928 		break;
2929 	case BPF_OBJ_GET_INFO_BY_FD:
2930 		err = bpf_obj_get_info_by_fd(&attr, uattr);
2931 		break;
2932 	case BPF_RAW_TRACEPOINT_OPEN:
2933 		err = bpf_raw_tracepoint_open(&attr);
2934 		break;
2935 	case BPF_BTF_LOAD:
2936 		err = bpf_btf_load(&attr);
2937 		break;
2938 	case BPF_BTF_GET_FD_BY_ID:
2939 		err = bpf_btf_get_fd_by_id(&attr);
2940 		break;
2941 	case BPF_TASK_FD_QUERY:
2942 		err = bpf_task_fd_query(&attr, uattr);
2943 		break;
2944 	case BPF_MAP_LOOKUP_AND_DELETE_ELEM:
2945 		err = map_lookup_and_delete_elem(&attr);
2946 		break;
2947 	default:
2948 		err = -EINVAL;
2949 		break;
2950 	}
2951 
2952 	return err;
2953 }
2954