xref: /openbmc/linux/kernel/bpf/syscall.c (revision 9f99d983)
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-cgroup.h>
6 #include <linux/bpf_trace.h>
7 #include <linux/bpf_lirc.h>
8 #include <linux/bpf_verifier.h>
9 #include <linux/btf.h>
10 #include <linux/syscalls.h>
11 #include <linux/slab.h>
12 #include <linux/sched/signal.h>
13 #include <linux/vmalloc.h>
14 #include <linux/mmzone.h>
15 #include <linux/anon_inodes.h>
16 #include <linux/fdtable.h>
17 #include <linux/file.h>
18 #include <linux/fs.h>
19 #include <linux/license.h>
20 #include <linux/filter.h>
21 #include <linux/kernel.h>
22 #include <linux/idr.h>
23 #include <linux/cred.h>
24 #include <linux/timekeeping.h>
25 #include <linux/ctype.h>
26 #include <linux/nospec.h>
27 #include <linux/audit.h>
28 #include <uapi/linux/btf.h>
29 #include <linux/pgtable.h>
30 #include <linux/bpf_lsm.h>
31 #include <linux/poll.h>
32 #include <linux/bpf-netns.h>
33 #include <linux/rcupdate_trace.h>
34 #include <linux/memcontrol.h>
35 
36 #define IS_FD_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || \
37 			  (map)->map_type == BPF_MAP_TYPE_CGROUP_ARRAY || \
38 			  (map)->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS)
39 #define IS_FD_PROG_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PROG_ARRAY)
40 #define IS_FD_HASH(map) ((map)->map_type == BPF_MAP_TYPE_HASH_OF_MAPS)
41 #define IS_FD_MAP(map) (IS_FD_ARRAY(map) || IS_FD_PROG_ARRAY(map) || \
42 			IS_FD_HASH(map))
43 
44 #define BPF_OBJ_FLAG_MASK   (BPF_F_RDONLY | BPF_F_WRONLY)
45 
46 DEFINE_PER_CPU(int, bpf_prog_active);
47 static DEFINE_IDR(prog_idr);
48 static DEFINE_SPINLOCK(prog_idr_lock);
49 static DEFINE_IDR(map_idr);
50 static DEFINE_SPINLOCK(map_idr_lock);
51 static DEFINE_IDR(link_idr);
52 static DEFINE_SPINLOCK(link_idr_lock);
53 
54 int sysctl_unprivileged_bpf_disabled __read_mostly =
55 	IS_BUILTIN(CONFIG_BPF_UNPRIV_DEFAULT_OFF) ? 2 : 0;
56 
57 static const struct bpf_map_ops * const bpf_map_types[] = {
58 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type)
59 #define BPF_MAP_TYPE(_id, _ops) \
60 	[_id] = &_ops,
61 #define BPF_LINK_TYPE(_id, _name)
62 #include <linux/bpf_types.h>
63 #undef BPF_PROG_TYPE
64 #undef BPF_MAP_TYPE
65 #undef BPF_LINK_TYPE
66 };
67 
68 /*
69  * If we're handed a bigger struct than we know of, ensure all the unknown bits
70  * are 0 - i.e. new user-space does not rely on any kernel feature extensions
71  * we don't know about yet.
72  *
73  * There is a ToCToU between this function call and the following
74  * copy_from_user() call. However, this is not a concern since this function is
75  * meant to be a future-proofing of bits.
76  */
77 int bpf_check_uarg_tail_zero(bpfptr_t uaddr,
78 			     size_t expected_size,
79 			     size_t actual_size)
80 {
81 	int res;
82 
83 	if (unlikely(actual_size > PAGE_SIZE))	/* silly large */
84 		return -E2BIG;
85 
86 	if (actual_size <= expected_size)
87 		return 0;
88 
89 	if (uaddr.is_kernel)
90 		res = memchr_inv(uaddr.kernel + expected_size, 0,
91 				 actual_size - expected_size) == NULL;
92 	else
93 		res = check_zeroed_user(uaddr.user + expected_size,
94 					actual_size - expected_size);
95 	if (res < 0)
96 		return res;
97 	return res ? 0 : -E2BIG;
98 }
99 
100 const struct bpf_map_ops bpf_map_offload_ops = {
101 	.map_meta_equal = bpf_map_meta_equal,
102 	.map_alloc = bpf_map_offload_map_alloc,
103 	.map_free = bpf_map_offload_map_free,
104 	.map_check_btf = map_check_no_btf,
105 };
106 
107 static struct bpf_map *find_and_alloc_map(union bpf_attr *attr)
108 {
109 	const struct bpf_map_ops *ops;
110 	u32 type = attr->map_type;
111 	struct bpf_map *map;
112 	int err;
113 
114 	if (type >= ARRAY_SIZE(bpf_map_types))
115 		return ERR_PTR(-EINVAL);
116 	type = array_index_nospec(type, ARRAY_SIZE(bpf_map_types));
117 	ops = bpf_map_types[type];
118 	if (!ops)
119 		return ERR_PTR(-EINVAL);
120 
121 	if (ops->map_alloc_check) {
122 		err = ops->map_alloc_check(attr);
123 		if (err)
124 			return ERR_PTR(err);
125 	}
126 	if (attr->map_ifindex)
127 		ops = &bpf_map_offload_ops;
128 	map = ops->map_alloc(attr);
129 	if (IS_ERR(map))
130 		return map;
131 	map->ops = ops;
132 	map->map_type = type;
133 	return map;
134 }
135 
136 static void bpf_map_write_active_inc(struct bpf_map *map)
137 {
138 	atomic64_inc(&map->writecnt);
139 }
140 
141 static void bpf_map_write_active_dec(struct bpf_map *map)
142 {
143 	atomic64_dec(&map->writecnt);
144 }
145 
146 bool bpf_map_write_active(const struct bpf_map *map)
147 {
148 	return atomic64_read(&map->writecnt) != 0;
149 }
150 
151 static u32 bpf_map_value_size(const struct bpf_map *map)
152 {
153 	if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
154 	    map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH ||
155 	    map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY ||
156 	    map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE)
157 		return round_up(map->value_size, 8) * num_possible_cpus();
158 	else if (IS_FD_MAP(map))
159 		return sizeof(u32);
160 	else
161 		return  map->value_size;
162 }
163 
164 static void maybe_wait_bpf_programs(struct bpf_map *map)
165 {
166 	/* Wait for any running BPF programs to complete so that
167 	 * userspace, when we return to it, knows that all programs
168 	 * that could be running use the new map value.
169 	 */
170 	if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS ||
171 	    map->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS)
172 		synchronize_rcu();
173 }
174 
175 static int bpf_map_update_value(struct bpf_map *map, struct fd f, void *key,
176 				void *value, __u64 flags)
177 {
178 	int err;
179 
180 	/* Need to create a kthread, thus must support schedule */
181 	if (bpf_map_is_dev_bound(map)) {
182 		return bpf_map_offload_update_elem(map, key, value, flags);
183 	} else if (map->map_type == BPF_MAP_TYPE_CPUMAP ||
184 		   map->map_type == BPF_MAP_TYPE_STRUCT_OPS) {
185 		return map->ops->map_update_elem(map, key, value, flags);
186 	} else if (map->map_type == BPF_MAP_TYPE_SOCKHASH ||
187 		   map->map_type == BPF_MAP_TYPE_SOCKMAP) {
188 		return sock_map_update_elem_sys(map, key, value, flags);
189 	} else if (IS_FD_PROG_ARRAY(map)) {
190 		return bpf_fd_array_map_update_elem(map, f.file, key, value,
191 						    flags);
192 	}
193 
194 	bpf_disable_instrumentation();
195 	if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
196 	    map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
197 		err = bpf_percpu_hash_update(map, key, value, flags);
198 	} else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) {
199 		err = bpf_percpu_array_update(map, key, value, flags);
200 	} else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) {
201 		err = bpf_percpu_cgroup_storage_update(map, key, value,
202 						       flags);
203 	} else if (IS_FD_ARRAY(map)) {
204 		rcu_read_lock();
205 		err = bpf_fd_array_map_update_elem(map, f.file, key, value,
206 						   flags);
207 		rcu_read_unlock();
208 	} else if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) {
209 		rcu_read_lock();
210 		err = bpf_fd_htab_map_update_elem(map, f.file, key, value,
211 						  flags);
212 		rcu_read_unlock();
213 	} else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) {
214 		/* rcu_read_lock() is not needed */
215 		err = bpf_fd_reuseport_array_update_elem(map, key, value,
216 							 flags);
217 	} else if (map->map_type == BPF_MAP_TYPE_QUEUE ||
218 		   map->map_type == BPF_MAP_TYPE_STACK ||
219 		   map->map_type == BPF_MAP_TYPE_BLOOM_FILTER) {
220 		err = map->ops->map_push_elem(map, value, flags);
221 	} else {
222 		rcu_read_lock();
223 		err = map->ops->map_update_elem(map, key, value, flags);
224 		rcu_read_unlock();
225 	}
226 	bpf_enable_instrumentation();
227 	maybe_wait_bpf_programs(map);
228 
229 	return err;
230 }
231 
232 static int bpf_map_copy_value(struct bpf_map *map, void *key, void *value,
233 			      __u64 flags)
234 {
235 	void *ptr;
236 	int err;
237 
238 	if (bpf_map_is_dev_bound(map))
239 		return bpf_map_offload_lookup_elem(map, key, value);
240 
241 	bpf_disable_instrumentation();
242 	if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
243 	    map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
244 		err = bpf_percpu_hash_copy(map, key, value);
245 	} else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) {
246 		err = bpf_percpu_array_copy(map, key, value);
247 	} else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) {
248 		err = bpf_percpu_cgroup_storage_copy(map, key, value);
249 	} else if (map->map_type == BPF_MAP_TYPE_STACK_TRACE) {
250 		err = bpf_stackmap_copy(map, key, value);
251 	} else if (IS_FD_ARRAY(map) || IS_FD_PROG_ARRAY(map)) {
252 		err = bpf_fd_array_map_lookup_elem(map, key, value);
253 	} else if (IS_FD_HASH(map)) {
254 		err = bpf_fd_htab_map_lookup_elem(map, key, value);
255 	} else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) {
256 		err = bpf_fd_reuseport_array_lookup_elem(map, key, value);
257 	} else if (map->map_type == BPF_MAP_TYPE_QUEUE ||
258 		   map->map_type == BPF_MAP_TYPE_STACK ||
259 		   map->map_type == BPF_MAP_TYPE_BLOOM_FILTER) {
260 		err = map->ops->map_peek_elem(map, value);
261 	} else if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS) {
262 		/* struct_ops map requires directly updating "value" */
263 		err = bpf_struct_ops_map_sys_lookup_elem(map, key, value);
264 	} else {
265 		rcu_read_lock();
266 		if (map->ops->map_lookup_elem_sys_only)
267 			ptr = map->ops->map_lookup_elem_sys_only(map, key);
268 		else
269 			ptr = map->ops->map_lookup_elem(map, key);
270 		if (IS_ERR(ptr)) {
271 			err = PTR_ERR(ptr);
272 		} else if (!ptr) {
273 			err = -ENOENT;
274 		} else {
275 			err = 0;
276 			if (flags & BPF_F_LOCK)
277 				/* lock 'ptr' and copy everything but lock */
278 				copy_map_value_locked(map, value, ptr, true);
279 			else
280 				copy_map_value(map, value, ptr);
281 			/* mask lock and timer, since value wasn't zero inited */
282 			check_and_init_map_value(map, value);
283 		}
284 		rcu_read_unlock();
285 	}
286 
287 	bpf_enable_instrumentation();
288 	maybe_wait_bpf_programs(map);
289 
290 	return err;
291 }
292 
293 /* Please, do not use this function outside from the map creation path
294  * (e.g. in map update path) without taking care of setting the active
295  * memory cgroup (see at bpf_map_kmalloc_node() for example).
296  */
297 static void *__bpf_map_area_alloc(u64 size, int numa_node, bool mmapable)
298 {
299 	/* We really just want to fail instead of triggering OOM killer
300 	 * under memory pressure, therefore we set __GFP_NORETRY to kmalloc,
301 	 * which is used for lower order allocation requests.
302 	 *
303 	 * It has been observed that higher order allocation requests done by
304 	 * vmalloc with __GFP_NORETRY being set might fail due to not trying
305 	 * to reclaim memory from the page cache, thus we set
306 	 * __GFP_RETRY_MAYFAIL to avoid such situations.
307 	 */
308 
309 	const gfp_t gfp = __GFP_NOWARN | __GFP_ZERO | __GFP_ACCOUNT;
310 	unsigned int flags = 0;
311 	unsigned long align = 1;
312 	void *area;
313 
314 	if (size >= SIZE_MAX)
315 		return NULL;
316 
317 	/* kmalloc()'ed memory can't be mmap()'ed */
318 	if (mmapable) {
319 		BUG_ON(!PAGE_ALIGNED(size));
320 		align = SHMLBA;
321 		flags = VM_USERMAP;
322 	} else if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) {
323 		area = kmalloc_node(size, gfp | GFP_USER | __GFP_NORETRY,
324 				    numa_node);
325 		if (area != NULL)
326 			return area;
327 	}
328 
329 	return __vmalloc_node_range(size, align, VMALLOC_START, VMALLOC_END,
330 			gfp | GFP_KERNEL | __GFP_RETRY_MAYFAIL, PAGE_KERNEL,
331 			flags, numa_node, __builtin_return_address(0));
332 }
333 
334 void *bpf_map_area_alloc(u64 size, int numa_node)
335 {
336 	return __bpf_map_area_alloc(size, numa_node, false);
337 }
338 
339 void *bpf_map_area_mmapable_alloc(u64 size, int numa_node)
340 {
341 	return __bpf_map_area_alloc(size, numa_node, true);
342 }
343 
344 void bpf_map_area_free(void *area)
345 {
346 	kvfree(area);
347 }
348 
349 static u32 bpf_map_flags_retain_permanent(u32 flags)
350 {
351 	/* Some map creation flags are not tied to the map object but
352 	 * rather to the map fd instead, so they have no meaning upon
353 	 * map object inspection since multiple file descriptors with
354 	 * different (access) properties can exist here. Thus, given
355 	 * this has zero meaning for the map itself, lets clear these
356 	 * from here.
357 	 */
358 	return flags & ~(BPF_F_RDONLY | BPF_F_WRONLY);
359 }
360 
361 void bpf_map_init_from_attr(struct bpf_map *map, union bpf_attr *attr)
362 {
363 	map->map_type = attr->map_type;
364 	map->key_size = attr->key_size;
365 	map->value_size = attr->value_size;
366 	map->max_entries = attr->max_entries;
367 	map->map_flags = bpf_map_flags_retain_permanent(attr->map_flags);
368 	map->numa_node = bpf_map_attr_numa_node(attr);
369 	map->map_extra = attr->map_extra;
370 }
371 
372 static int bpf_map_alloc_id(struct bpf_map *map)
373 {
374 	int id;
375 
376 	idr_preload(GFP_KERNEL);
377 	spin_lock_bh(&map_idr_lock);
378 	id = idr_alloc_cyclic(&map_idr, map, 1, INT_MAX, GFP_ATOMIC);
379 	if (id > 0)
380 		map->id = id;
381 	spin_unlock_bh(&map_idr_lock);
382 	idr_preload_end();
383 
384 	if (WARN_ON_ONCE(!id))
385 		return -ENOSPC;
386 
387 	return id > 0 ? 0 : id;
388 }
389 
390 void bpf_map_free_id(struct bpf_map *map, bool do_idr_lock)
391 {
392 	unsigned long flags;
393 
394 	/* Offloaded maps are removed from the IDR store when their device
395 	 * disappears - even if someone holds an fd to them they are unusable,
396 	 * the memory is gone, all ops will fail; they are simply waiting for
397 	 * refcnt to drop to be freed.
398 	 */
399 	if (!map->id)
400 		return;
401 
402 	if (do_idr_lock)
403 		spin_lock_irqsave(&map_idr_lock, flags);
404 	else
405 		__acquire(&map_idr_lock);
406 
407 	idr_remove(&map_idr, map->id);
408 	map->id = 0;
409 
410 	if (do_idr_lock)
411 		spin_unlock_irqrestore(&map_idr_lock, flags);
412 	else
413 		__release(&map_idr_lock);
414 }
415 
416 #ifdef CONFIG_MEMCG_KMEM
417 static void bpf_map_save_memcg(struct bpf_map *map)
418 {
419 	map->memcg = get_mem_cgroup_from_mm(current->mm);
420 }
421 
422 static void bpf_map_release_memcg(struct bpf_map *map)
423 {
424 	mem_cgroup_put(map->memcg);
425 }
426 
427 void *bpf_map_kmalloc_node(const struct bpf_map *map, size_t size, gfp_t flags,
428 			   int node)
429 {
430 	struct mem_cgroup *old_memcg;
431 	void *ptr;
432 
433 	old_memcg = set_active_memcg(map->memcg);
434 	ptr = kmalloc_node(size, flags | __GFP_ACCOUNT, node);
435 	set_active_memcg(old_memcg);
436 
437 	return ptr;
438 }
439 
440 void *bpf_map_kzalloc(const struct bpf_map *map, size_t size, gfp_t flags)
441 {
442 	struct mem_cgroup *old_memcg;
443 	void *ptr;
444 
445 	old_memcg = set_active_memcg(map->memcg);
446 	ptr = kzalloc(size, flags | __GFP_ACCOUNT);
447 	set_active_memcg(old_memcg);
448 
449 	return ptr;
450 }
451 
452 void __percpu *bpf_map_alloc_percpu(const struct bpf_map *map, size_t size,
453 				    size_t align, gfp_t flags)
454 {
455 	struct mem_cgroup *old_memcg;
456 	void __percpu *ptr;
457 
458 	old_memcg = set_active_memcg(map->memcg);
459 	ptr = __alloc_percpu_gfp(size, align, flags | __GFP_ACCOUNT);
460 	set_active_memcg(old_memcg);
461 
462 	return ptr;
463 }
464 
465 #else
466 static void bpf_map_save_memcg(struct bpf_map *map)
467 {
468 }
469 
470 static void bpf_map_release_memcg(struct bpf_map *map)
471 {
472 }
473 #endif
474 
475 /* called from workqueue */
476 static void bpf_map_free_deferred(struct work_struct *work)
477 {
478 	struct bpf_map *map = container_of(work, struct bpf_map, work);
479 
480 	security_bpf_map_free(map);
481 	bpf_map_release_memcg(map);
482 	/* implementation dependent freeing */
483 	map->ops->map_free(map);
484 }
485 
486 static void bpf_map_put_uref(struct bpf_map *map)
487 {
488 	if (atomic64_dec_and_test(&map->usercnt)) {
489 		if (map->ops->map_release_uref)
490 			map->ops->map_release_uref(map);
491 	}
492 }
493 
494 /* decrement map refcnt and schedule it for freeing via workqueue
495  * (unrelying map implementation ops->map_free() might sleep)
496  */
497 static void __bpf_map_put(struct bpf_map *map, bool do_idr_lock)
498 {
499 	if (atomic64_dec_and_test(&map->refcnt)) {
500 		/* bpf_map_free_id() must be called first */
501 		bpf_map_free_id(map, do_idr_lock);
502 		btf_put(map->btf);
503 		INIT_WORK(&map->work, bpf_map_free_deferred);
504 		schedule_work(&map->work);
505 	}
506 }
507 
508 void bpf_map_put(struct bpf_map *map)
509 {
510 	__bpf_map_put(map, true);
511 }
512 EXPORT_SYMBOL_GPL(bpf_map_put);
513 
514 void bpf_map_put_with_uref(struct bpf_map *map)
515 {
516 	bpf_map_put_uref(map);
517 	bpf_map_put(map);
518 }
519 
520 static int bpf_map_release(struct inode *inode, struct file *filp)
521 {
522 	struct bpf_map *map = filp->private_data;
523 
524 	if (map->ops->map_release)
525 		map->ops->map_release(map, filp);
526 
527 	bpf_map_put_with_uref(map);
528 	return 0;
529 }
530 
531 static fmode_t map_get_sys_perms(struct bpf_map *map, struct fd f)
532 {
533 	fmode_t mode = f.file->f_mode;
534 
535 	/* Our file permissions may have been overridden by global
536 	 * map permissions facing syscall side.
537 	 */
538 	if (READ_ONCE(map->frozen))
539 		mode &= ~FMODE_CAN_WRITE;
540 	return mode;
541 }
542 
543 #ifdef CONFIG_PROC_FS
544 /* Provides an approximation of the map's memory footprint.
545  * Used only to provide a backward compatibility and display
546  * a reasonable "memlock" info.
547  */
548 static unsigned long bpf_map_memory_footprint(const struct bpf_map *map)
549 {
550 	unsigned long size;
551 
552 	size = round_up(map->key_size + bpf_map_value_size(map), 8);
553 
554 	return round_up(map->max_entries * size, PAGE_SIZE);
555 }
556 
557 static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp)
558 {
559 	const struct bpf_map *map = filp->private_data;
560 	const struct bpf_array *array;
561 	u32 type = 0, jited = 0;
562 
563 	if (map->map_type == BPF_MAP_TYPE_PROG_ARRAY) {
564 		array = container_of(map, struct bpf_array, map);
565 		spin_lock(&array->aux->owner.lock);
566 		type  = array->aux->owner.type;
567 		jited = array->aux->owner.jited;
568 		spin_unlock(&array->aux->owner.lock);
569 	}
570 
571 	seq_printf(m,
572 		   "map_type:\t%u\n"
573 		   "key_size:\t%u\n"
574 		   "value_size:\t%u\n"
575 		   "max_entries:\t%u\n"
576 		   "map_flags:\t%#x\n"
577 		   "map_extra:\t%#llx\n"
578 		   "memlock:\t%lu\n"
579 		   "map_id:\t%u\n"
580 		   "frozen:\t%u\n",
581 		   map->map_type,
582 		   map->key_size,
583 		   map->value_size,
584 		   map->max_entries,
585 		   map->map_flags,
586 		   (unsigned long long)map->map_extra,
587 		   bpf_map_memory_footprint(map),
588 		   map->id,
589 		   READ_ONCE(map->frozen));
590 	if (type) {
591 		seq_printf(m, "owner_prog_type:\t%u\n", type);
592 		seq_printf(m, "owner_jited:\t%u\n", jited);
593 	}
594 }
595 #endif
596 
597 static ssize_t bpf_dummy_read(struct file *filp, char __user *buf, size_t siz,
598 			      loff_t *ppos)
599 {
600 	/* We need this handler such that alloc_file() enables
601 	 * f_mode with FMODE_CAN_READ.
602 	 */
603 	return -EINVAL;
604 }
605 
606 static ssize_t bpf_dummy_write(struct file *filp, const char __user *buf,
607 			       size_t siz, loff_t *ppos)
608 {
609 	/* We need this handler such that alloc_file() enables
610 	 * f_mode with FMODE_CAN_WRITE.
611 	 */
612 	return -EINVAL;
613 }
614 
615 /* called for any extra memory-mapped regions (except initial) */
616 static void bpf_map_mmap_open(struct vm_area_struct *vma)
617 {
618 	struct bpf_map *map = vma->vm_file->private_data;
619 
620 	if (vma->vm_flags & VM_MAYWRITE)
621 		bpf_map_write_active_inc(map);
622 }
623 
624 /* called for all unmapped memory region (including initial) */
625 static void bpf_map_mmap_close(struct vm_area_struct *vma)
626 {
627 	struct bpf_map *map = vma->vm_file->private_data;
628 
629 	if (vma->vm_flags & VM_MAYWRITE)
630 		bpf_map_write_active_dec(map);
631 }
632 
633 static const struct vm_operations_struct bpf_map_default_vmops = {
634 	.open		= bpf_map_mmap_open,
635 	.close		= bpf_map_mmap_close,
636 };
637 
638 static int bpf_map_mmap(struct file *filp, struct vm_area_struct *vma)
639 {
640 	struct bpf_map *map = filp->private_data;
641 	int err;
642 
643 	if (!map->ops->map_mmap || map_value_has_spin_lock(map) ||
644 	    map_value_has_timer(map))
645 		return -ENOTSUPP;
646 
647 	if (!(vma->vm_flags & VM_SHARED))
648 		return -EINVAL;
649 
650 	mutex_lock(&map->freeze_mutex);
651 
652 	if (vma->vm_flags & VM_WRITE) {
653 		if (map->frozen) {
654 			err = -EPERM;
655 			goto out;
656 		}
657 		/* map is meant to be read-only, so do not allow mapping as
658 		 * writable, because it's possible to leak a writable page
659 		 * reference and allows user-space to still modify it after
660 		 * freezing, while verifier will assume contents do not change
661 		 */
662 		if (map->map_flags & BPF_F_RDONLY_PROG) {
663 			err = -EACCES;
664 			goto out;
665 		}
666 	}
667 
668 	/* set default open/close callbacks */
669 	vma->vm_ops = &bpf_map_default_vmops;
670 	vma->vm_private_data = map;
671 	vma->vm_flags &= ~VM_MAYEXEC;
672 	if (!(vma->vm_flags & VM_WRITE))
673 		/* disallow re-mapping with PROT_WRITE */
674 		vma->vm_flags &= ~VM_MAYWRITE;
675 
676 	err = map->ops->map_mmap(map, vma);
677 	if (err)
678 		goto out;
679 
680 	if (vma->vm_flags & VM_MAYWRITE)
681 		bpf_map_write_active_inc(map);
682 out:
683 	mutex_unlock(&map->freeze_mutex);
684 	return err;
685 }
686 
687 static __poll_t bpf_map_poll(struct file *filp, struct poll_table_struct *pts)
688 {
689 	struct bpf_map *map = filp->private_data;
690 
691 	if (map->ops->map_poll)
692 		return map->ops->map_poll(map, filp, pts);
693 
694 	return EPOLLERR;
695 }
696 
697 const struct file_operations bpf_map_fops = {
698 #ifdef CONFIG_PROC_FS
699 	.show_fdinfo	= bpf_map_show_fdinfo,
700 #endif
701 	.release	= bpf_map_release,
702 	.read		= bpf_dummy_read,
703 	.write		= bpf_dummy_write,
704 	.mmap		= bpf_map_mmap,
705 	.poll		= bpf_map_poll,
706 };
707 
708 int bpf_map_new_fd(struct bpf_map *map, int flags)
709 {
710 	int ret;
711 
712 	ret = security_bpf_map(map, OPEN_FMODE(flags));
713 	if (ret < 0)
714 		return ret;
715 
716 	return anon_inode_getfd("bpf-map", &bpf_map_fops, map,
717 				flags | O_CLOEXEC);
718 }
719 
720 int bpf_get_file_flag(int flags)
721 {
722 	if ((flags & BPF_F_RDONLY) && (flags & BPF_F_WRONLY))
723 		return -EINVAL;
724 	if (flags & BPF_F_RDONLY)
725 		return O_RDONLY;
726 	if (flags & BPF_F_WRONLY)
727 		return O_WRONLY;
728 	return O_RDWR;
729 }
730 
731 /* helper macro to check that unused fields 'union bpf_attr' are zero */
732 #define CHECK_ATTR(CMD) \
733 	memchr_inv((void *) &attr->CMD##_LAST_FIELD + \
734 		   sizeof(attr->CMD##_LAST_FIELD), 0, \
735 		   sizeof(*attr) - \
736 		   offsetof(union bpf_attr, CMD##_LAST_FIELD) - \
737 		   sizeof(attr->CMD##_LAST_FIELD)) != NULL
738 
739 /* dst and src must have at least "size" number of bytes.
740  * Return strlen on success and < 0 on error.
741  */
742 int bpf_obj_name_cpy(char *dst, const char *src, unsigned int size)
743 {
744 	const char *end = src + size;
745 	const char *orig_src = src;
746 
747 	memset(dst, 0, size);
748 	/* Copy all isalnum(), '_' and '.' chars. */
749 	while (src < end && *src) {
750 		if (!isalnum(*src) &&
751 		    *src != '_' && *src != '.')
752 			return -EINVAL;
753 		*dst++ = *src++;
754 	}
755 
756 	/* No '\0' found in "size" number of bytes */
757 	if (src == end)
758 		return -EINVAL;
759 
760 	return src - orig_src;
761 }
762 
763 int map_check_no_btf(const struct bpf_map *map,
764 		     const struct btf *btf,
765 		     const struct btf_type *key_type,
766 		     const struct btf_type *value_type)
767 {
768 	return -ENOTSUPP;
769 }
770 
771 static int map_check_btf(struct bpf_map *map, const struct btf *btf,
772 			 u32 btf_key_id, u32 btf_value_id)
773 {
774 	const struct btf_type *key_type, *value_type;
775 	u32 key_size, value_size;
776 	int ret = 0;
777 
778 	/* Some maps allow key to be unspecified. */
779 	if (btf_key_id) {
780 		key_type = btf_type_id_size(btf, &btf_key_id, &key_size);
781 		if (!key_type || key_size != map->key_size)
782 			return -EINVAL;
783 	} else {
784 		key_type = btf_type_by_id(btf, 0);
785 		if (!map->ops->map_check_btf)
786 			return -EINVAL;
787 	}
788 
789 	value_type = btf_type_id_size(btf, &btf_value_id, &value_size);
790 	if (!value_type || value_size != map->value_size)
791 		return -EINVAL;
792 
793 	map->spin_lock_off = btf_find_spin_lock(btf, value_type);
794 
795 	if (map_value_has_spin_lock(map)) {
796 		if (map->map_flags & BPF_F_RDONLY_PROG)
797 			return -EACCES;
798 		if (map->map_type != BPF_MAP_TYPE_HASH &&
799 		    map->map_type != BPF_MAP_TYPE_ARRAY &&
800 		    map->map_type != BPF_MAP_TYPE_CGROUP_STORAGE &&
801 		    map->map_type != BPF_MAP_TYPE_SK_STORAGE &&
802 		    map->map_type != BPF_MAP_TYPE_INODE_STORAGE &&
803 		    map->map_type != BPF_MAP_TYPE_TASK_STORAGE)
804 			return -ENOTSUPP;
805 		if (map->spin_lock_off + sizeof(struct bpf_spin_lock) >
806 		    map->value_size) {
807 			WARN_ONCE(1,
808 				  "verifier bug spin_lock_off %d value_size %d\n",
809 				  map->spin_lock_off, map->value_size);
810 			return -EFAULT;
811 		}
812 	}
813 
814 	map->timer_off = btf_find_timer(btf, value_type);
815 	if (map_value_has_timer(map)) {
816 		if (map->map_flags & BPF_F_RDONLY_PROG)
817 			return -EACCES;
818 		if (map->map_type != BPF_MAP_TYPE_HASH &&
819 		    map->map_type != BPF_MAP_TYPE_LRU_HASH &&
820 		    map->map_type != BPF_MAP_TYPE_ARRAY)
821 			return -EOPNOTSUPP;
822 	}
823 
824 	if (map->ops->map_check_btf)
825 		ret = map->ops->map_check_btf(map, btf, key_type, value_type);
826 
827 	return ret;
828 }
829 
830 #define BPF_MAP_CREATE_LAST_FIELD map_extra
831 /* called via syscall */
832 static int map_create(union bpf_attr *attr)
833 {
834 	int numa_node = bpf_map_attr_numa_node(attr);
835 	struct bpf_map *map;
836 	int f_flags;
837 	int err;
838 
839 	err = CHECK_ATTR(BPF_MAP_CREATE);
840 	if (err)
841 		return -EINVAL;
842 
843 	if (attr->btf_vmlinux_value_type_id) {
844 		if (attr->map_type != BPF_MAP_TYPE_STRUCT_OPS ||
845 		    attr->btf_key_type_id || attr->btf_value_type_id)
846 			return -EINVAL;
847 	} else if (attr->btf_key_type_id && !attr->btf_value_type_id) {
848 		return -EINVAL;
849 	}
850 
851 	if (attr->map_type != BPF_MAP_TYPE_BLOOM_FILTER &&
852 	    attr->map_extra != 0)
853 		return -EINVAL;
854 
855 	f_flags = bpf_get_file_flag(attr->map_flags);
856 	if (f_flags < 0)
857 		return f_flags;
858 
859 	if (numa_node != NUMA_NO_NODE &&
860 	    ((unsigned int)numa_node >= nr_node_ids ||
861 	     !node_online(numa_node)))
862 		return -EINVAL;
863 
864 	/* find map type and init map: hashtable vs rbtree vs bloom vs ... */
865 	map = find_and_alloc_map(attr);
866 	if (IS_ERR(map))
867 		return PTR_ERR(map);
868 
869 	err = bpf_obj_name_cpy(map->name, attr->map_name,
870 			       sizeof(attr->map_name));
871 	if (err < 0)
872 		goto free_map;
873 
874 	atomic64_set(&map->refcnt, 1);
875 	atomic64_set(&map->usercnt, 1);
876 	mutex_init(&map->freeze_mutex);
877 
878 	map->spin_lock_off = -EINVAL;
879 	map->timer_off = -EINVAL;
880 	if (attr->btf_key_type_id || attr->btf_value_type_id ||
881 	    /* Even the map's value is a kernel's struct,
882 	     * the bpf_prog.o must have BTF to begin with
883 	     * to figure out the corresponding kernel's
884 	     * counter part.  Thus, attr->btf_fd has
885 	     * to be valid also.
886 	     */
887 	    attr->btf_vmlinux_value_type_id) {
888 		struct btf *btf;
889 
890 		btf = btf_get_by_fd(attr->btf_fd);
891 		if (IS_ERR(btf)) {
892 			err = PTR_ERR(btf);
893 			goto free_map;
894 		}
895 		if (btf_is_kernel(btf)) {
896 			btf_put(btf);
897 			err = -EACCES;
898 			goto free_map;
899 		}
900 		map->btf = btf;
901 
902 		if (attr->btf_value_type_id) {
903 			err = map_check_btf(map, btf, attr->btf_key_type_id,
904 					    attr->btf_value_type_id);
905 			if (err)
906 				goto free_map;
907 		}
908 
909 		map->btf_key_type_id = attr->btf_key_type_id;
910 		map->btf_value_type_id = attr->btf_value_type_id;
911 		map->btf_vmlinux_value_type_id =
912 			attr->btf_vmlinux_value_type_id;
913 	}
914 
915 	err = security_bpf_map_alloc(map);
916 	if (err)
917 		goto free_map;
918 
919 	err = bpf_map_alloc_id(map);
920 	if (err)
921 		goto free_map_sec;
922 
923 	bpf_map_save_memcg(map);
924 
925 	err = bpf_map_new_fd(map, f_flags);
926 	if (err < 0) {
927 		/* failed to allocate fd.
928 		 * bpf_map_put_with_uref() is needed because the above
929 		 * bpf_map_alloc_id() has published the map
930 		 * to the userspace and the userspace may
931 		 * have refcnt-ed it through BPF_MAP_GET_FD_BY_ID.
932 		 */
933 		bpf_map_put_with_uref(map);
934 		return err;
935 	}
936 
937 	return err;
938 
939 free_map_sec:
940 	security_bpf_map_free(map);
941 free_map:
942 	btf_put(map->btf);
943 	map->ops->map_free(map);
944 	return err;
945 }
946 
947 /* if error is returned, fd is released.
948  * On success caller should complete fd access with matching fdput()
949  */
950 struct bpf_map *__bpf_map_get(struct fd f)
951 {
952 	if (!f.file)
953 		return ERR_PTR(-EBADF);
954 	if (f.file->f_op != &bpf_map_fops) {
955 		fdput(f);
956 		return ERR_PTR(-EINVAL);
957 	}
958 
959 	return f.file->private_data;
960 }
961 
962 void bpf_map_inc(struct bpf_map *map)
963 {
964 	atomic64_inc(&map->refcnt);
965 }
966 EXPORT_SYMBOL_GPL(bpf_map_inc);
967 
968 void bpf_map_inc_with_uref(struct bpf_map *map)
969 {
970 	atomic64_inc(&map->refcnt);
971 	atomic64_inc(&map->usercnt);
972 }
973 EXPORT_SYMBOL_GPL(bpf_map_inc_with_uref);
974 
975 struct bpf_map *bpf_map_get(u32 ufd)
976 {
977 	struct fd f = fdget(ufd);
978 	struct bpf_map *map;
979 
980 	map = __bpf_map_get(f);
981 	if (IS_ERR(map))
982 		return map;
983 
984 	bpf_map_inc(map);
985 	fdput(f);
986 
987 	return map;
988 }
989 
990 struct bpf_map *bpf_map_get_with_uref(u32 ufd)
991 {
992 	struct fd f = fdget(ufd);
993 	struct bpf_map *map;
994 
995 	map = __bpf_map_get(f);
996 	if (IS_ERR(map))
997 		return map;
998 
999 	bpf_map_inc_with_uref(map);
1000 	fdput(f);
1001 
1002 	return map;
1003 }
1004 
1005 /* map_idr_lock should have been held */
1006 static struct bpf_map *__bpf_map_inc_not_zero(struct bpf_map *map, bool uref)
1007 {
1008 	int refold;
1009 
1010 	refold = atomic64_fetch_add_unless(&map->refcnt, 1, 0);
1011 	if (!refold)
1012 		return ERR_PTR(-ENOENT);
1013 	if (uref)
1014 		atomic64_inc(&map->usercnt);
1015 
1016 	return map;
1017 }
1018 
1019 struct bpf_map *bpf_map_inc_not_zero(struct bpf_map *map)
1020 {
1021 	spin_lock_bh(&map_idr_lock);
1022 	map = __bpf_map_inc_not_zero(map, false);
1023 	spin_unlock_bh(&map_idr_lock);
1024 
1025 	return map;
1026 }
1027 EXPORT_SYMBOL_GPL(bpf_map_inc_not_zero);
1028 
1029 int __weak bpf_stackmap_copy(struct bpf_map *map, void *key, void *value)
1030 {
1031 	return -ENOTSUPP;
1032 }
1033 
1034 static void *__bpf_copy_key(void __user *ukey, u64 key_size)
1035 {
1036 	if (key_size)
1037 		return vmemdup_user(ukey, key_size);
1038 
1039 	if (ukey)
1040 		return ERR_PTR(-EINVAL);
1041 
1042 	return NULL;
1043 }
1044 
1045 static void *___bpf_copy_key(bpfptr_t ukey, u64 key_size)
1046 {
1047 	if (key_size)
1048 		return kvmemdup_bpfptr(ukey, key_size);
1049 
1050 	if (!bpfptr_is_null(ukey))
1051 		return ERR_PTR(-EINVAL);
1052 
1053 	return NULL;
1054 }
1055 
1056 /* last field in 'union bpf_attr' used by this command */
1057 #define BPF_MAP_LOOKUP_ELEM_LAST_FIELD flags
1058 
1059 static int map_lookup_elem(union bpf_attr *attr)
1060 {
1061 	void __user *ukey = u64_to_user_ptr(attr->key);
1062 	void __user *uvalue = u64_to_user_ptr(attr->value);
1063 	int ufd = attr->map_fd;
1064 	struct bpf_map *map;
1065 	void *key, *value;
1066 	u32 value_size;
1067 	struct fd f;
1068 	int err;
1069 
1070 	if (CHECK_ATTR(BPF_MAP_LOOKUP_ELEM))
1071 		return -EINVAL;
1072 
1073 	if (attr->flags & ~BPF_F_LOCK)
1074 		return -EINVAL;
1075 
1076 	f = fdget(ufd);
1077 	map = __bpf_map_get(f);
1078 	if (IS_ERR(map))
1079 		return PTR_ERR(map);
1080 	if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) {
1081 		err = -EPERM;
1082 		goto err_put;
1083 	}
1084 
1085 	if ((attr->flags & BPF_F_LOCK) &&
1086 	    !map_value_has_spin_lock(map)) {
1087 		err = -EINVAL;
1088 		goto err_put;
1089 	}
1090 
1091 	key = __bpf_copy_key(ukey, map->key_size);
1092 	if (IS_ERR(key)) {
1093 		err = PTR_ERR(key);
1094 		goto err_put;
1095 	}
1096 
1097 	value_size = bpf_map_value_size(map);
1098 
1099 	err = -ENOMEM;
1100 	value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN);
1101 	if (!value)
1102 		goto free_key;
1103 
1104 	if (map->map_type == BPF_MAP_TYPE_BLOOM_FILTER) {
1105 		if (copy_from_user(value, uvalue, value_size))
1106 			err = -EFAULT;
1107 		else
1108 			err = bpf_map_copy_value(map, key, value, attr->flags);
1109 		goto free_value;
1110 	}
1111 
1112 	err = bpf_map_copy_value(map, key, value, attr->flags);
1113 	if (err)
1114 		goto free_value;
1115 
1116 	err = -EFAULT;
1117 	if (copy_to_user(uvalue, value, value_size) != 0)
1118 		goto free_value;
1119 
1120 	err = 0;
1121 
1122 free_value:
1123 	kvfree(value);
1124 free_key:
1125 	kvfree(key);
1126 err_put:
1127 	fdput(f);
1128 	return err;
1129 }
1130 
1131 
1132 #define BPF_MAP_UPDATE_ELEM_LAST_FIELD flags
1133 
1134 static int map_update_elem(union bpf_attr *attr, bpfptr_t uattr)
1135 {
1136 	bpfptr_t ukey = make_bpfptr(attr->key, uattr.is_kernel);
1137 	bpfptr_t uvalue = make_bpfptr(attr->value, uattr.is_kernel);
1138 	int ufd = attr->map_fd;
1139 	struct bpf_map *map;
1140 	void *key, *value;
1141 	u32 value_size;
1142 	struct fd f;
1143 	int err;
1144 
1145 	if (CHECK_ATTR(BPF_MAP_UPDATE_ELEM))
1146 		return -EINVAL;
1147 
1148 	f = fdget(ufd);
1149 	map = __bpf_map_get(f);
1150 	if (IS_ERR(map))
1151 		return PTR_ERR(map);
1152 	bpf_map_write_active_inc(map);
1153 	if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
1154 		err = -EPERM;
1155 		goto err_put;
1156 	}
1157 
1158 	if ((attr->flags & BPF_F_LOCK) &&
1159 	    !map_value_has_spin_lock(map)) {
1160 		err = -EINVAL;
1161 		goto err_put;
1162 	}
1163 
1164 	key = ___bpf_copy_key(ukey, map->key_size);
1165 	if (IS_ERR(key)) {
1166 		err = PTR_ERR(key);
1167 		goto err_put;
1168 	}
1169 
1170 	value_size = bpf_map_value_size(map);
1171 
1172 	err = -ENOMEM;
1173 	value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN);
1174 	if (!value)
1175 		goto free_key;
1176 
1177 	err = -EFAULT;
1178 	if (copy_from_bpfptr(value, uvalue, value_size) != 0)
1179 		goto free_value;
1180 
1181 	err = bpf_map_update_value(map, f, key, value, attr->flags);
1182 
1183 free_value:
1184 	kvfree(value);
1185 free_key:
1186 	kvfree(key);
1187 err_put:
1188 	bpf_map_write_active_dec(map);
1189 	fdput(f);
1190 	return err;
1191 }
1192 
1193 #define BPF_MAP_DELETE_ELEM_LAST_FIELD key
1194 
1195 static int map_delete_elem(union bpf_attr *attr)
1196 {
1197 	void __user *ukey = u64_to_user_ptr(attr->key);
1198 	int ufd = attr->map_fd;
1199 	struct bpf_map *map;
1200 	struct fd f;
1201 	void *key;
1202 	int err;
1203 
1204 	if (CHECK_ATTR(BPF_MAP_DELETE_ELEM))
1205 		return -EINVAL;
1206 
1207 	f = fdget(ufd);
1208 	map = __bpf_map_get(f);
1209 	if (IS_ERR(map))
1210 		return PTR_ERR(map);
1211 	bpf_map_write_active_inc(map);
1212 	if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
1213 		err = -EPERM;
1214 		goto err_put;
1215 	}
1216 
1217 	key = __bpf_copy_key(ukey, map->key_size);
1218 	if (IS_ERR(key)) {
1219 		err = PTR_ERR(key);
1220 		goto err_put;
1221 	}
1222 
1223 	if (bpf_map_is_dev_bound(map)) {
1224 		err = bpf_map_offload_delete_elem(map, key);
1225 		goto out;
1226 	} else if (IS_FD_PROG_ARRAY(map) ||
1227 		   map->map_type == BPF_MAP_TYPE_STRUCT_OPS) {
1228 		/* These maps require sleepable context */
1229 		err = map->ops->map_delete_elem(map, key);
1230 		goto out;
1231 	}
1232 
1233 	bpf_disable_instrumentation();
1234 	rcu_read_lock();
1235 	err = map->ops->map_delete_elem(map, key);
1236 	rcu_read_unlock();
1237 	bpf_enable_instrumentation();
1238 	maybe_wait_bpf_programs(map);
1239 out:
1240 	kvfree(key);
1241 err_put:
1242 	bpf_map_write_active_dec(map);
1243 	fdput(f);
1244 	return err;
1245 }
1246 
1247 /* last field in 'union bpf_attr' used by this command */
1248 #define BPF_MAP_GET_NEXT_KEY_LAST_FIELD next_key
1249 
1250 static int map_get_next_key(union bpf_attr *attr)
1251 {
1252 	void __user *ukey = u64_to_user_ptr(attr->key);
1253 	void __user *unext_key = u64_to_user_ptr(attr->next_key);
1254 	int ufd = attr->map_fd;
1255 	struct bpf_map *map;
1256 	void *key, *next_key;
1257 	struct fd f;
1258 	int err;
1259 
1260 	if (CHECK_ATTR(BPF_MAP_GET_NEXT_KEY))
1261 		return -EINVAL;
1262 
1263 	f = fdget(ufd);
1264 	map = __bpf_map_get(f);
1265 	if (IS_ERR(map))
1266 		return PTR_ERR(map);
1267 	if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) {
1268 		err = -EPERM;
1269 		goto err_put;
1270 	}
1271 
1272 	if (ukey) {
1273 		key = __bpf_copy_key(ukey, map->key_size);
1274 		if (IS_ERR(key)) {
1275 			err = PTR_ERR(key);
1276 			goto err_put;
1277 		}
1278 	} else {
1279 		key = NULL;
1280 	}
1281 
1282 	err = -ENOMEM;
1283 	next_key = kvmalloc(map->key_size, GFP_USER);
1284 	if (!next_key)
1285 		goto free_key;
1286 
1287 	if (bpf_map_is_dev_bound(map)) {
1288 		err = bpf_map_offload_get_next_key(map, key, next_key);
1289 		goto out;
1290 	}
1291 
1292 	rcu_read_lock();
1293 	err = map->ops->map_get_next_key(map, key, next_key);
1294 	rcu_read_unlock();
1295 out:
1296 	if (err)
1297 		goto free_next_key;
1298 
1299 	err = -EFAULT;
1300 	if (copy_to_user(unext_key, next_key, map->key_size) != 0)
1301 		goto free_next_key;
1302 
1303 	err = 0;
1304 
1305 free_next_key:
1306 	kvfree(next_key);
1307 free_key:
1308 	kvfree(key);
1309 err_put:
1310 	fdput(f);
1311 	return err;
1312 }
1313 
1314 int generic_map_delete_batch(struct bpf_map *map,
1315 			     const union bpf_attr *attr,
1316 			     union bpf_attr __user *uattr)
1317 {
1318 	void __user *keys = u64_to_user_ptr(attr->batch.keys);
1319 	u32 cp, max_count;
1320 	int err = 0;
1321 	void *key;
1322 
1323 	if (attr->batch.elem_flags & ~BPF_F_LOCK)
1324 		return -EINVAL;
1325 
1326 	if ((attr->batch.elem_flags & BPF_F_LOCK) &&
1327 	    !map_value_has_spin_lock(map)) {
1328 		return -EINVAL;
1329 	}
1330 
1331 	max_count = attr->batch.count;
1332 	if (!max_count)
1333 		return 0;
1334 
1335 	key = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN);
1336 	if (!key)
1337 		return -ENOMEM;
1338 
1339 	for (cp = 0; cp < max_count; cp++) {
1340 		err = -EFAULT;
1341 		if (copy_from_user(key, keys + cp * map->key_size,
1342 				   map->key_size))
1343 			break;
1344 
1345 		if (bpf_map_is_dev_bound(map)) {
1346 			err = bpf_map_offload_delete_elem(map, key);
1347 			break;
1348 		}
1349 
1350 		bpf_disable_instrumentation();
1351 		rcu_read_lock();
1352 		err = map->ops->map_delete_elem(map, key);
1353 		rcu_read_unlock();
1354 		bpf_enable_instrumentation();
1355 		maybe_wait_bpf_programs(map);
1356 		if (err)
1357 			break;
1358 		cond_resched();
1359 	}
1360 	if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp)))
1361 		err = -EFAULT;
1362 
1363 	kvfree(key);
1364 	return err;
1365 }
1366 
1367 int generic_map_update_batch(struct bpf_map *map,
1368 			     const union bpf_attr *attr,
1369 			     union bpf_attr __user *uattr)
1370 {
1371 	void __user *values = u64_to_user_ptr(attr->batch.values);
1372 	void __user *keys = u64_to_user_ptr(attr->batch.keys);
1373 	u32 value_size, cp, max_count;
1374 	int ufd = attr->batch.map_fd;
1375 	void *key, *value;
1376 	struct fd f;
1377 	int err = 0;
1378 
1379 	if (attr->batch.elem_flags & ~BPF_F_LOCK)
1380 		return -EINVAL;
1381 
1382 	if ((attr->batch.elem_flags & BPF_F_LOCK) &&
1383 	    !map_value_has_spin_lock(map)) {
1384 		return -EINVAL;
1385 	}
1386 
1387 	value_size = bpf_map_value_size(map);
1388 
1389 	max_count = attr->batch.count;
1390 	if (!max_count)
1391 		return 0;
1392 
1393 	key = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN);
1394 	if (!key)
1395 		return -ENOMEM;
1396 
1397 	value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN);
1398 	if (!value) {
1399 		kvfree(key);
1400 		return -ENOMEM;
1401 	}
1402 
1403 	f = fdget(ufd); /* bpf_map_do_batch() guarantees ufd is valid */
1404 	for (cp = 0; cp < max_count; cp++) {
1405 		err = -EFAULT;
1406 		if (copy_from_user(key, keys + cp * map->key_size,
1407 		    map->key_size) ||
1408 		    copy_from_user(value, values + cp * value_size, value_size))
1409 			break;
1410 
1411 		err = bpf_map_update_value(map, f, key, value,
1412 					   attr->batch.elem_flags);
1413 
1414 		if (err)
1415 			break;
1416 		cond_resched();
1417 	}
1418 
1419 	if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp)))
1420 		err = -EFAULT;
1421 
1422 	kvfree(value);
1423 	kvfree(key);
1424 	fdput(f);
1425 	return err;
1426 }
1427 
1428 #define MAP_LOOKUP_RETRIES 3
1429 
1430 int generic_map_lookup_batch(struct bpf_map *map,
1431 				    const union bpf_attr *attr,
1432 				    union bpf_attr __user *uattr)
1433 {
1434 	void __user *uobatch = u64_to_user_ptr(attr->batch.out_batch);
1435 	void __user *ubatch = u64_to_user_ptr(attr->batch.in_batch);
1436 	void __user *values = u64_to_user_ptr(attr->batch.values);
1437 	void __user *keys = u64_to_user_ptr(attr->batch.keys);
1438 	void *buf, *buf_prevkey, *prev_key, *key, *value;
1439 	int err, retry = MAP_LOOKUP_RETRIES;
1440 	u32 value_size, cp, max_count;
1441 
1442 	if (attr->batch.elem_flags & ~BPF_F_LOCK)
1443 		return -EINVAL;
1444 
1445 	if ((attr->batch.elem_flags & BPF_F_LOCK) &&
1446 	    !map_value_has_spin_lock(map))
1447 		return -EINVAL;
1448 
1449 	value_size = bpf_map_value_size(map);
1450 
1451 	max_count = attr->batch.count;
1452 	if (!max_count)
1453 		return 0;
1454 
1455 	if (put_user(0, &uattr->batch.count))
1456 		return -EFAULT;
1457 
1458 	buf_prevkey = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN);
1459 	if (!buf_prevkey)
1460 		return -ENOMEM;
1461 
1462 	buf = kvmalloc(map->key_size + value_size, GFP_USER | __GFP_NOWARN);
1463 	if (!buf) {
1464 		kvfree(buf_prevkey);
1465 		return -ENOMEM;
1466 	}
1467 
1468 	err = -EFAULT;
1469 	prev_key = NULL;
1470 	if (ubatch && copy_from_user(buf_prevkey, ubatch, map->key_size))
1471 		goto free_buf;
1472 	key = buf;
1473 	value = key + map->key_size;
1474 	if (ubatch)
1475 		prev_key = buf_prevkey;
1476 
1477 	for (cp = 0; cp < max_count;) {
1478 		rcu_read_lock();
1479 		err = map->ops->map_get_next_key(map, prev_key, key);
1480 		rcu_read_unlock();
1481 		if (err)
1482 			break;
1483 		err = bpf_map_copy_value(map, key, value,
1484 					 attr->batch.elem_flags);
1485 
1486 		if (err == -ENOENT) {
1487 			if (retry) {
1488 				retry--;
1489 				continue;
1490 			}
1491 			err = -EINTR;
1492 			break;
1493 		}
1494 
1495 		if (err)
1496 			goto free_buf;
1497 
1498 		if (copy_to_user(keys + cp * map->key_size, key,
1499 				 map->key_size)) {
1500 			err = -EFAULT;
1501 			goto free_buf;
1502 		}
1503 		if (copy_to_user(values + cp * value_size, value, value_size)) {
1504 			err = -EFAULT;
1505 			goto free_buf;
1506 		}
1507 
1508 		if (!prev_key)
1509 			prev_key = buf_prevkey;
1510 
1511 		swap(prev_key, key);
1512 		retry = MAP_LOOKUP_RETRIES;
1513 		cp++;
1514 		cond_resched();
1515 	}
1516 
1517 	if (err == -EFAULT)
1518 		goto free_buf;
1519 
1520 	if ((copy_to_user(&uattr->batch.count, &cp, sizeof(cp)) ||
1521 		    (cp && copy_to_user(uobatch, prev_key, map->key_size))))
1522 		err = -EFAULT;
1523 
1524 free_buf:
1525 	kvfree(buf_prevkey);
1526 	kvfree(buf);
1527 	return err;
1528 }
1529 
1530 #define BPF_MAP_LOOKUP_AND_DELETE_ELEM_LAST_FIELD flags
1531 
1532 static int map_lookup_and_delete_elem(union bpf_attr *attr)
1533 {
1534 	void __user *ukey = u64_to_user_ptr(attr->key);
1535 	void __user *uvalue = u64_to_user_ptr(attr->value);
1536 	int ufd = attr->map_fd;
1537 	struct bpf_map *map;
1538 	void *key, *value;
1539 	u32 value_size;
1540 	struct fd f;
1541 	int err;
1542 
1543 	if (CHECK_ATTR(BPF_MAP_LOOKUP_AND_DELETE_ELEM))
1544 		return -EINVAL;
1545 
1546 	if (attr->flags & ~BPF_F_LOCK)
1547 		return -EINVAL;
1548 
1549 	f = fdget(ufd);
1550 	map = __bpf_map_get(f);
1551 	if (IS_ERR(map))
1552 		return PTR_ERR(map);
1553 	bpf_map_write_active_inc(map);
1554 	if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ) ||
1555 	    !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
1556 		err = -EPERM;
1557 		goto err_put;
1558 	}
1559 
1560 	if (attr->flags &&
1561 	    (map->map_type == BPF_MAP_TYPE_QUEUE ||
1562 	     map->map_type == BPF_MAP_TYPE_STACK)) {
1563 		err = -EINVAL;
1564 		goto err_put;
1565 	}
1566 
1567 	if ((attr->flags & BPF_F_LOCK) &&
1568 	    !map_value_has_spin_lock(map)) {
1569 		err = -EINVAL;
1570 		goto err_put;
1571 	}
1572 
1573 	key = __bpf_copy_key(ukey, map->key_size);
1574 	if (IS_ERR(key)) {
1575 		err = PTR_ERR(key);
1576 		goto err_put;
1577 	}
1578 
1579 	value_size = bpf_map_value_size(map);
1580 
1581 	err = -ENOMEM;
1582 	value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN);
1583 	if (!value)
1584 		goto free_key;
1585 
1586 	err = -ENOTSUPP;
1587 	if (map->map_type == BPF_MAP_TYPE_QUEUE ||
1588 	    map->map_type == BPF_MAP_TYPE_STACK) {
1589 		err = map->ops->map_pop_elem(map, value);
1590 	} else if (map->map_type == BPF_MAP_TYPE_HASH ||
1591 		   map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
1592 		   map->map_type == BPF_MAP_TYPE_LRU_HASH ||
1593 		   map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
1594 		if (!bpf_map_is_dev_bound(map)) {
1595 			bpf_disable_instrumentation();
1596 			rcu_read_lock();
1597 			err = map->ops->map_lookup_and_delete_elem(map, key, value, attr->flags);
1598 			rcu_read_unlock();
1599 			bpf_enable_instrumentation();
1600 		}
1601 	}
1602 
1603 	if (err)
1604 		goto free_value;
1605 
1606 	if (copy_to_user(uvalue, value, value_size) != 0) {
1607 		err = -EFAULT;
1608 		goto free_value;
1609 	}
1610 
1611 	err = 0;
1612 
1613 free_value:
1614 	kvfree(value);
1615 free_key:
1616 	kvfree(key);
1617 err_put:
1618 	bpf_map_write_active_dec(map);
1619 	fdput(f);
1620 	return err;
1621 }
1622 
1623 #define BPF_MAP_FREEZE_LAST_FIELD map_fd
1624 
1625 static int map_freeze(const union bpf_attr *attr)
1626 {
1627 	int err = 0, ufd = attr->map_fd;
1628 	struct bpf_map *map;
1629 	struct fd f;
1630 
1631 	if (CHECK_ATTR(BPF_MAP_FREEZE))
1632 		return -EINVAL;
1633 
1634 	f = fdget(ufd);
1635 	map = __bpf_map_get(f);
1636 	if (IS_ERR(map))
1637 		return PTR_ERR(map);
1638 
1639 	if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS ||
1640 	    map_value_has_timer(map)) {
1641 		fdput(f);
1642 		return -ENOTSUPP;
1643 	}
1644 
1645 	mutex_lock(&map->freeze_mutex);
1646 	if (bpf_map_write_active(map)) {
1647 		err = -EBUSY;
1648 		goto err_put;
1649 	}
1650 	if (READ_ONCE(map->frozen)) {
1651 		err = -EBUSY;
1652 		goto err_put;
1653 	}
1654 	if (!bpf_capable()) {
1655 		err = -EPERM;
1656 		goto err_put;
1657 	}
1658 
1659 	WRITE_ONCE(map->frozen, true);
1660 err_put:
1661 	mutex_unlock(&map->freeze_mutex);
1662 	fdput(f);
1663 	return err;
1664 }
1665 
1666 static const struct bpf_prog_ops * const bpf_prog_types[] = {
1667 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) \
1668 	[_id] = & _name ## _prog_ops,
1669 #define BPF_MAP_TYPE(_id, _ops)
1670 #define BPF_LINK_TYPE(_id, _name)
1671 #include <linux/bpf_types.h>
1672 #undef BPF_PROG_TYPE
1673 #undef BPF_MAP_TYPE
1674 #undef BPF_LINK_TYPE
1675 };
1676 
1677 static int find_prog_type(enum bpf_prog_type type, struct bpf_prog *prog)
1678 {
1679 	const struct bpf_prog_ops *ops;
1680 
1681 	if (type >= ARRAY_SIZE(bpf_prog_types))
1682 		return -EINVAL;
1683 	type = array_index_nospec(type, ARRAY_SIZE(bpf_prog_types));
1684 	ops = bpf_prog_types[type];
1685 	if (!ops)
1686 		return -EINVAL;
1687 
1688 	if (!bpf_prog_is_dev_bound(prog->aux))
1689 		prog->aux->ops = ops;
1690 	else
1691 		prog->aux->ops = &bpf_offload_prog_ops;
1692 	prog->type = type;
1693 	return 0;
1694 }
1695 
1696 enum bpf_audit {
1697 	BPF_AUDIT_LOAD,
1698 	BPF_AUDIT_UNLOAD,
1699 	BPF_AUDIT_MAX,
1700 };
1701 
1702 static const char * const bpf_audit_str[BPF_AUDIT_MAX] = {
1703 	[BPF_AUDIT_LOAD]   = "LOAD",
1704 	[BPF_AUDIT_UNLOAD] = "UNLOAD",
1705 };
1706 
1707 static void bpf_audit_prog(const struct bpf_prog *prog, unsigned int op)
1708 {
1709 	struct audit_context *ctx = NULL;
1710 	struct audit_buffer *ab;
1711 
1712 	if (WARN_ON_ONCE(op >= BPF_AUDIT_MAX))
1713 		return;
1714 	if (audit_enabled == AUDIT_OFF)
1715 		return;
1716 	if (op == BPF_AUDIT_LOAD)
1717 		ctx = audit_context();
1718 	ab = audit_log_start(ctx, GFP_ATOMIC, AUDIT_BPF);
1719 	if (unlikely(!ab))
1720 		return;
1721 	audit_log_format(ab, "prog-id=%u op=%s",
1722 			 prog->aux->id, bpf_audit_str[op]);
1723 	audit_log_end(ab);
1724 }
1725 
1726 static int bpf_prog_alloc_id(struct bpf_prog *prog)
1727 {
1728 	int id;
1729 
1730 	idr_preload(GFP_KERNEL);
1731 	spin_lock_bh(&prog_idr_lock);
1732 	id = idr_alloc_cyclic(&prog_idr, prog, 1, INT_MAX, GFP_ATOMIC);
1733 	if (id > 0)
1734 		prog->aux->id = id;
1735 	spin_unlock_bh(&prog_idr_lock);
1736 	idr_preload_end();
1737 
1738 	/* id is in [1, INT_MAX) */
1739 	if (WARN_ON_ONCE(!id))
1740 		return -ENOSPC;
1741 
1742 	return id > 0 ? 0 : id;
1743 }
1744 
1745 void bpf_prog_free_id(struct bpf_prog *prog, bool do_idr_lock)
1746 {
1747 	unsigned long flags;
1748 
1749 	/* cBPF to eBPF migrations are currently not in the idr store.
1750 	 * Offloaded programs are removed from the store when their device
1751 	 * disappears - even if someone grabs an fd to them they are unusable,
1752 	 * simply waiting for refcnt to drop to be freed.
1753 	 */
1754 	if (!prog->aux->id)
1755 		return;
1756 
1757 	if (do_idr_lock)
1758 		spin_lock_irqsave(&prog_idr_lock, flags);
1759 	else
1760 		__acquire(&prog_idr_lock);
1761 
1762 	idr_remove(&prog_idr, prog->aux->id);
1763 	prog->aux->id = 0;
1764 
1765 	if (do_idr_lock)
1766 		spin_unlock_irqrestore(&prog_idr_lock, flags);
1767 	else
1768 		__release(&prog_idr_lock);
1769 }
1770 
1771 static void __bpf_prog_put_rcu(struct rcu_head *rcu)
1772 {
1773 	struct bpf_prog_aux *aux = container_of(rcu, struct bpf_prog_aux, rcu);
1774 
1775 	kvfree(aux->func_info);
1776 	kfree(aux->func_info_aux);
1777 	free_uid(aux->user);
1778 	security_bpf_prog_free(aux);
1779 	bpf_prog_free(aux->prog);
1780 }
1781 
1782 static void __bpf_prog_put_noref(struct bpf_prog *prog, bool deferred)
1783 {
1784 	bpf_prog_kallsyms_del_all(prog);
1785 	btf_put(prog->aux->btf);
1786 	kvfree(prog->aux->jited_linfo);
1787 	kvfree(prog->aux->linfo);
1788 	kfree(prog->aux->kfunc_tab);
1789 	if (prog->aux->attach_btf)
1790 		btf_put(prog->aux->attach_btf);
1791 
1792 	if (deferred) {
1793 		if (prog->aux->sleepable)
1794 			call_rcu_tasks_trace(&prog->aux->rcu, __bpf_prog_put_rcu);
1795 		else
1796 			call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu);
1797 	} else {
1798 		__bpf_prog_put_rcu(&prog->aux->rcu);
1799 	}
1800 }
1801 
1802 static void bpf_prog_put_deferred(struct work_struct *work)
1803 {
1804 	struct bpf_prog_aux *aux;
1805 	struct bpf_prog *prog;
1806 
1807 	aux = container_of(work, struct bpf_prog_aux, work);
1808 	prog = aux->prog;
1809 	perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_UNLOAD, 0);
1810 	bpf_audit_prog(prog, BPF_AUDIT_UNLOAD);
1811 	__bpf_prog_put_noref(prog, true);
1812 }
1813 
1814 static void __bpf_prog_put(struct bpf_prog *prog, bool do_idr_lock)
1815 {
1816 	struct bpf_prog_aux *aux = prog->aux;
1817 
1818 	if (atomic64_dec_and_test(&aux->refcnt)) {
1819 		/* bpf_prog_free_id() must be called first */
1820 		bpf_prog_free_id(prog, do_idr_lock);
1821 
1822 		if (in_irq() || irqs_disabled()) {
1823 			INIT_WORK(&aux->work, bpf_prog_put_deferred);
1824 			schedule_work(&aux->work);
1825 		} else {
1826 			bpf_prog_put_deferred(&aux->work);
1827 		}
1828 	}
1829 }
1830 
1831 void bpf_prog_put(struct bpf_prog *prog)
1832 {
1833 	__bpf_prog_put(prog, true);
1834 }
1835 EXPORT_SYMBOL_GPL(bpf_prog_put);
1836 
1837 static int bpf_prog_release(struct inode *inode, struct file *filp)
1838 {
1839 	struct bpf_prog *prog = filp->private_data;
1840 
1841 	bpf_prog_put(prog);
1842 	return 0;
1843 }
1844 
1845 struct bpf_prog_kstats {
1846 	u64 nsecs;
1847 	u64 cnt;
1848 	u64 misses;
1849 };
1850 
1851 static void bpf_prog_get_stats(const struct bpf_prog *prog,
1852 			       struct bpf_prog_kstats *stats)
1853 {
1854 	u64 nsecs = 0, cnt = 0, misses = 0;
1855 	int cpu;
1856 
1857 	for_each_possible_cpu(cpu) {
1858 		const struct bpf_prog_stats *st;
1859 		unsigned int start;
1860 		u64 tnsecs, tcnt, tmisses;
1861 
1862 		st = per_cpu_ptr(prog->stats, cpu);
1863 		do {
1864 			start = u64_stats_fetch_begin_irq(&st->syncp);
1865 			tnsecs = u64_stats_read(&st->nsecs);
1866 			tcnt = u64_stats_read(&st->cnt);
1867 			tmisses = u64_stats_read(&st->misses);
1868 		} while (u64_stats_fetch_retry_irq(&st->syncp, start));
1869 		nsecs += tnsecs;
1870 		cnt += tcnt;
1871 		misses += tmisses;
1872 	}
1873 	stats->nsecs = nsecs;
1874 	stats->cnt = cnt;
1875 	stats->misses = misses;
1876 }
1877 
1878 #ifdef CONFIG_PROC_FS
1879 static void bpf_prog_show_fdinfo(struct seq_file *m, struct file *filp)
1880 {
1881 	const struct bpf_prog *prog = filp->private_data;
1882 	char prog_tag[sizeof(prog->tag) * 2 + 1] = { };
1883 	struct bpf_prog_kstats stats;
1884 
1885 	bpf_prog_get_stats(prog, &stats);
1886 	bin2hex(prog_tag, prog->tag, sizeof(prog->tag));
1887 	seq_printf(m,
1888 		   "prog_type:\t%u\n"
1889 		   "prog_jited:\t%u\n"
1890 		   "prog_tag:\t%s\n"
1891 		   "memlock:\t%llu\n"
1892 		   "prog_id:\t%u\n"
1893 		   "run_time_ns:\t%llu\n"
1894 		   "run_cnt:\t%llu\n"
1895 		   "recursion_misses:\t%llu\n"
1896 		   "verified_insns:\t%u\n",
1897 		   prog->type,
1898 		   prog->jited,
1899 		   prog_tag,
1900 		   prog->pages * 1ULL << PAGE_SHIFT,
1901 		   prog->aux->id,
1902 		   stats.nsecs,
1903 		   stats.cnt,
1904 		   stats.misses,
1905 		   prog->aux->verified_insns);
1906 }
1907 #endif
1908 
1909 const struct file_operations bpf_prog_fops = {
1910 #ifdef CONFIG_PROC_FS
1911 	.show_fdinfo	= bpf_prog_show_fdinfo,
1912 #endif
1913 	.release	= bpf_prog_release,
1914 	.read		= bpf_dummy_read,
1915 	.write		= bpf_dummy_write,
1916 };
1917 
1918 int bpf_prog_new_fd(struct bpf_prog *prog)
1919 {
1920 	int ret;
1921 
1922 	ret = security_bpf_prog(prog);
1923 	if (ret < 0)
1924 		return ret;
1925 
1926 	return anon_inode_getfd("bpf-prog", &bpf_prog_fops, prog,
1927 				O_RDWR | O_CLOEXEC);
1928 }
1929 
1930 static struct bpf_prog *____bpf_prog_get(struct fd f)
1931 {
1932 	if (!f.file)
1933 		return ERR_PTR(-EBADF);
1934 	if (f.file->f_op != &bpf_prog_fops) {
1935 		fdput(f);
1936 		return ERR_PTR(-EINVAL);
1937 	}
1938 
1939 	return f.file->private_data;
1940 }
1941 
1942 void bpf_prog_add(struct bpf_prog *prog, int i)
1943 {
1944 	atomic64_add(i, &prog->aux->refcnt);
1945 }
1946 EXPORT_SYMBOL_GPL(bpf_prog_add);
1947 
1948 void bpf_prog_sub(struct bpf_prog *prog, int i)
1949 {
1950 	/* Only to be used for undoing previous bpf_prog_add() in some
1951 	 * error path. We still know that another entity in our call
1952 	 * path holds a reference to the program, thus atomic_sub() can
1953 	 * be safely used in such cases!
1954 	 */
1955 	WARN_ON(atomic64_sub_return(i, &prog->aux->refcnt) == 0);
1956 }
1957 EXPORT_SYMBOL_GPL(bpf_prog_sub);
1958 
1959 void bpf_prog_inc(struct bpf_prog *prog)
1960 {
1961 	atomic64_inc(&prog->aux->refcnt);
1962 }
1963 EXPORT_SYMBOL_GPL(bpf_prog_inc);
1964 
1965 /* prog_idr_lock should have been held */
1966 struct bpf_prog *bpf_prog_inc_not_zero(struct bpf_prog *prog)
1967 {
1968 	int refold;
1969 
1970 	refold = atomic64_fetch_add_unless(&prog->aux->refcnt, 1, 0);
1971 
1972 	if (!refold)
1973 		return ERR_PTR(-ENOENT);
1974 
1975 	return prog;
1976 }
1977 EXPORT_SYMBOL_GPL(bpf_prog_inc_not_zero);
1978 
1979 bool bpf_prog_get_ok(struct bpf_prog *prog,
1980 			    enum bpf_prog_type *attach_type, bool attach_drv)
1981 {
1982 	/* not an attachment, just a refcount inc, always allow */
1983 	if (!attach_type)
1984 		return true;
1985 
1986 	if (prog->type != *attach_type)
1987 		return false;
1988 	if (bpf_prog_is_dev_bound(prog->aux) && !attach_drv)
1989 		return false;
1990 
1991 	return true;
1992 }
1993 
1994 static struct bpf_prog *__bpf_prog_get(u32 ufd, enum bpf_prog_type *attach_type,
1995 				       bool attach_drv)
1996 {
1997 	struct fd f = fdget(ufd);
1998 	struct bpf_prog *prog;
1999 
2000 	prog = ____bpf_prog_get(f);
2001 	if (IS_ERR(prog))
2002 		return prog;
2003 	if (!bpf_prog_get_ok(prog, attach_type, attach_drv)) {
2004 		prog = ERR_PTR(-EINVAL);
2005 		goto out;
2006 	}
2007 
2008 	bpf_prog_inc(prog);
2009 out:
2010 	fdput(f);
2011 	return prog;
2012 }
2013 
2014 struct bpf_prog *bpf_prog_get(u32 ufd)
2015 {
2016 	return __bpf_prog_get(ufd, NULL, false);
2017 }
2018 
2019 struct bpf_prog *bpf_prog_get_type_dev(u32 ufd, enum bpf_prog_type type,
2020 				       bool attach_drv)
2021 {
2022 	return __bpf_prog_get(ufd, &type, attach_drv);
2023 }
2024 EXPORT_SYMBOL_GPL(bpf_prog_get_type_dev);
2025 
2026 /* Initially all BPF programs could be loaded w/o specifying
2027  * expected_attach_type. Later for some of them specifying expected_attach_type
2028  * at load time became required so that program could be validated properly.
2029  * Programs of types that are allowed to be loaded both w/ and w/o (for
2030  * backward compatibility) expected_attach_type, should have the default attach
2031  * type assigned to expected_attach_type for the latter case, so that it can be
2032  * validated later at attach time.
2033  *
2034  * bpf_prog_load_fixup_attach_type() sets expected_attach_type in @attr if
2035  * prog type requires it but has some attach types that have to be backward
2036  * compatible.
2037  */
2038 static void bpf_prog_load_fixup_attach_type(union bpf_attr *attr)
2039 {
2040 	switch (attr->prog_type) {
2041 	case BPF_PROG_TYPE_CGROUP_SOCK:
2042 		/* Unfortunately BPF_ATTACH_TYPE_UNSPEC enumeration doesn't
2043 		 * exist so checking for non-zero is the way to go here.
2044 		 */
2045 		if (!attr->expected_attach_type)
2046 			attr->expected_attach_type =
2047 				BPF_CGROUP_INET_SOCK_CREATE;
2048 		break;
2049 	case BPF_PROG_TYPE_SK_REUSEPORT:
2050 		if (!attr->expected_attach_type)
2051 			attr->expected_attach_type =
2052 				BPF_SK_REUSEPORT_SELECT;
2053 		break;
2054 	}
2055 }
2056 
2057 static int
2058 bpf_prog_load_check_attach(enum bpf_prog_type prog_type,
2059 			   enum bpf_attach_type expected_attach_type,
2060 			   struct btf *attach_btf, u32 btf_id,
2061 			   struct bpf_prog *dst_prog)
2062 {
2063 	if (btf_id) {
2064 		if (btf_id > BTF_MAX_TYPE)
2065 			return -EINVAL;
2066 
2067 		if (!attach_btf && !dst_prog)
2068 			return -EINVAL;
2069 
2070 		switch (prog_type) {
2071 		case BPF_PROG_TYPE_TRACING:
2072 		case BPF_PROG_TYPE_LSM:
2073 		case BPF_PROG_TYPE_STRUCT_OPS:
2074 		case BPF_PROG_TYPE_EXT:
2075 			break;
2076 		default:
2077 			return -EINVAL;
2078 		}
2079 	}
2080 
2081 	if (attach_btf && (!btf_id || dst_prog))
2082 		return -EINVAL;
2083 
2084 	if (dst_prog && prog_type != BPF_PROG_TYPE_TRACING &&
2085 	    prog_type != BPF_PROG_TYPE_EXT)
2086 		return -EINVAL;
2087 
2088 	switch (prog_type) {
2089 	case BPF_PROG_TYPE_CGROUP_SOCK:
2090 		switch (expected_attach_type) {
2091 		case BPF_CGROUP_INET_SOCK_CREATE:
2092 		case BPF_CGROUP_INET_SOCK_RELEASE:
2093 		case BPF_CGROUP_INET4_POST_BIND:
2094 		case BPF_CGROUP_INET6_POST_BIND:
2095 			return 0;
2096 		default:
2097 			return -EINVAL;
2098 		}
2099 	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
2100 		switch (expected_attach_type) {
2101 		case BPF_CGROUP_INET4_BIND:
2102 		case BPF_CGROUP_INET6_BIND:
2103 		case BPF_CGROUP_INET4_CONNECT:
2104 		case BPF_CGROUP_INET6_CONNECT:
2105 		case BPF_CGROUP_INET4_GETPEERNAME:
2106 		case BPF_CGROUP_INET6_GETPEERNAME:
2107 		case BPF_CGROUP_INET4_GETSOCKNAME:
2108 		case BPF_CGROUP_INET6_GETSOCKNAME:
2109 		case BPF_CGROUP_UDP4_SENDMSG:
2110 		case BPF_CGROUP_UDP6_SENDMSG:
2111 		case BPF_CGROUP_UDP4_RECVMSG:
2112 		case BPF_CGROUP_UDP6_RECVMSG:
2113 			return 0;
2114 		default:
2115 			return -EINVAL;
2116 		}
2117 	case BPF_PROG_TYPE_CGROUP_SKB:
2118 		switch (expected_attach_type) {
2119 		case BPF_CGROUP_INET_INGRESS:
2120 		case BPF_CGROUP_INET_EGRESS:
2121 			return 0;
2122 		default:
2123 			return -EINVAL;
2124 		}
2125 	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
2126 		switch (expected_attach_type) {
2127 		case BPF_CGROUP_SETSOCKOPT:
2128 		case BPF_CGROUP_GETSOCKOPT:
2129 			return 0;
2130 		default:
2131 			return -EINVAL;
2132 		}
2133 	case BPF_PROG_TYPE_SK_LOOKUP:
2134 		if (expected_attach_type == BPF_SK_LOOKUP)
2135 			return 0;
2136 		return -EINVAL;
2137 	case BPF_PROG_TYPE_SK_REUSEPORT:
2138 		switch (expected_attach_type) {
2139 		case BPF_SK_REUSEPORT_SELECT:
2140 		case BPF_SK_REUSEPORT_SELECT_OR_MIGRATE:
2141 			return 0;
2142 		default:
2143 			return -EINVAL;
2144 		}
2145 	case BPF_PROG_TYPE_SYSCALL:
2146 	case BPF_PROG_TYPE_EXT:
2147 		if (expected_attach_type)
2148 			return -EINVAL;
2149 		fallthrough;
2150 	default:
2151 		return 0;
2152 	}
2153 }
2154 
2155 static bool is_net_admin_prog_type(enum bpf_prog_type prog_type)
2156 {
2157 	switch (prog_type) {
2158 	case BPF_PROG_TYPE_SCHED_CLS:
2159 	case BPF_PROG_TYPE_SCHED_ACT:
2160 	case BPF_PROG_TYPE_XDP:
2161 	case BPF_PROG_TYPE_LWT_IN:
2162 	case BPF_PROG_TYPE_LWT_OUT:
2163 	case BPF_PROG_TYPE_LWT_XMIT:
2164 	case BPF_PROG_TYPE_LWT_SEG6LOCAL:
2165 	case BPF_PROG_TYPE_SK_SKB:
2166 	case BPF_PROG_TYPE_SK_MSG:
2167 	case BPF_PROG_TYPE_LIRC_MODE2:
2168 	case BPF_PROG_TYPE_FLOW_DISSECTOR:
2169 	case BPF_PROG_TYPE_CGROUP_DEVICE:
2170 	case BPF_PROG_TYPE_CGROUP_SOCK:
2171 	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
2172 	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
2173 	case BPF_PROG_TYPE_CGROUP_SYSCTL:
2174 	case BPF_PROG_TYPE_SOCK_OPS:
2175 	case BPF_PROG_TYPE_EXT: /* extends any prog */
2176 		return true;
2177 	case BPF_PROG_TYPE_CGROUP_SKB:
2178 		/* always unpriv */
2179 	case BPF_PROG_TYPE_SK_REUSEPORT:
2180 		/* equivalent to SOCKET_FILTER. need CAP_BPF only */
2181 	default:
2182 		return false;
2183 	}
2184 }
2185 
2186 static bool is_perfmon_prog_type(enum bpf_prog_type prog_type)
2187 {
2188 	switch (prog_type) {
2189 	case BPF_PROG_TYPE_KPROBE:
2190 	case BPF_PROG_TYPE_TRACEPOINT:
2191 	case BPF_PROG_TYPE_PERF_EVENT:
2192 	case BPF_PROG_TYPE_RAW_TRACEPOINT:
2193 	case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE:
2194 	case BPF_PROG_TYPE_TRACING:
2195 	case BPF_PROG_TYPE_LSM:
2196 	case BPF_PROG_TYPE_STRUCT_OPS: /* has access to struct sock */
2197 	case BPF_PROG_TYPE_EXT: /* extends any prog */
2198 		return true;
2199 	default:
2200 		return false;
2201 	}
2202 }
2203 
2204 /* last field in 'union bpf_attr' used by this command */
2205 #define	BPF_PROG_LOAD_LAST_FIELD core_relo_rec_size
2206 
2207 static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr)
2208 {
2209 	enum bpf_prog_type type = attr->prog_type;
2210 	struct bpf_prog *prog, *dst_prog = NULL;
2211 	struct btf *attach_btf = NULL;
2212 	int err;
2213 	char license[128];
2214 	bool is_gpl;
2215 
2216 	if (CHECK_ATTR(BPF_PROG_LOAD))
2217 		return -EINVAL;
2218 
2219 	if (attr->prog_flags & ~(BPF_F_STRICT_ALIGNMENT |
2220 				 BPF_F_ANY_ALIGNMENT |
2221 				 BPF_F_TEST_STATE_FREQ |
2222 				 BPF_F_SLEEPABLE |
2223 				 BPF_F_TEST_RND_HI32))
2224 		return -EINVAL;
2225 
2226 	if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) &&
2227 	    (attr->prog_flags & BPF_F_ANY_ALIGNMENT) &&
2228 	    !bpf_capable())
2229 		return -EPERM;
2230 
2231 	/* copy eBPF program license from user space */
2232 	if (strncpy_from_bpfptr(license,
2233 				make_bpfptr(attr->license, uattr.is_kernel),
2234 				sizeof(license) - 1) < 0)
2235 		return -EFAULT;
2236 	license[sizeof(license) - 1] = 0;
2237 
2238 	/* eBPF programs must be GPL compatible to use GPL-ed functions */
2239 	is_gpl = license_is_gpl_compatible(license);
2240 
2241 	if (attr->insn_cnt == 0 ||
2242 	    attr->insn_cnt > (bpf_capable() ? BPF_COMPLEXITY_LIMIT_INSNS : BPF_MAXINSNS))
2243 		return -E2BIG;
2244 	if (type != BPF_PROG_TYPE_SOCKET_FILTER &&
2245 	    type != BPF_PROG_TYPE_CGROUP_SKB &&
2246 	    !bpf_capable())
2247 		return -EPERM;
2248 
2249 	if (is_net_admin_prog_type(type) && !capable(CAP_NET_ADMIN) && !capable(CAP_SYS_ADMIN))
2250 		return -EPERM;
2251 	if (is_perfmon_prog_type(type) && !perfmon_capable())
2252 		return -EPERM;
2253 
2254 	/* attach_prog_fd/attach_btf_obj_fd can specify fd of either bpf_prog
2255 	 * or btf, we need to check which one it is
2256 	 */
2257 	if (attr->attach_prog_fd) {
2258 		dst_prog = bpf_prog_get(attr->attach_prog_fd);
2259 		if (IS_ERR(dst_prog)) {
2260 			dst_prog = NULL;
2261 			attach_btf = btf_get_by_fd(attr->attach_btf_obj_fd);
2262 			if (IS_ERR(attach_btf))
2263 				return -EINVAL;
2264 			if (!btf_is_kernel(attach_btf)) {
2265 				/* attaching through specifying bpf_prog's BTF
2266 				 * objects directly might be supported eventually
2267 				 */
2268 				btf_put(attach_btf);
2269 				return -ENOTSUPP;
2270 			}
2271 		}
2272 	} else if (attr->attach_btf_id) {
2273 		/* fall back to vmlinux BTF, if BTF type ID is specified */
2274 		attach_btf = bpf_get_btf_vmlinux();
2275 		if (IS_ERR(attach_btf))
2276 			return PTR_ERR(attach_btf);
2277 		if (!attach_btf)
2278 			return -EINVAL;
2279 		btf_get(attach_btf);
2280 	}
2281 
2282 	bpf_prog_load_fixup_attach_type(attr);
2283 	if (bpf_prog_load_check_attach(type, attr->expected_attach_type,
2284 				       attach_btf, attr->attach_btf_id,
2285 				       dst_prog)) {
2286 		if (dst_prog)
2287 			bpf_prog_put(dst_prog);
2288 		if (attach_btf)
2289 			btf_put(attach_btf);
2290 		return -EINVAL;
2291 	}
2292 
2293 	/* plain bpf_prog allocation */
2294 	prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER);
2295 	if (!prog) {
2296 		if (dst_prog)
2297 			bpf_prog_put(dst_prog);
2298 		if (attach_btf)
2299 			btf_put(attach_btf);
2300 		return -ENOMEM;
2301 	}
2302 
2303 	prog->expected_attach_type = attr->expected_attach_type;
2304 	prog->aux->attach_btf = attach_btf;
2305 	prog->aux->attach_btf_id = attr->attach_btf_id;
2306 	prog->aux->dst_prog = dst_prog;
2307 	prog->aux->offload_requested = !!attr->prog_ifindex;
2308 	prog->aux->sleepable = attr->prog_flags & BPF_F_SLEEPABLE;
2309 
2310 	err = security_bpf_prog_alloc(prog->aux);
2311 	if (err)
2312 		goto free_prog;
2313 
2314 	prog->aux->user = get_current_user();
2315 	prog->len = attr->insn_cnt;
2316 
2317 	err = -EFAULT;
2318 	if (copy_from_bpfptr(prog->insns,
2319 			     make_bpfptr(attr->insns, uattr.is_kernel),
2320 			     bpf_prog_insn_size(prog)) != 0)
2321 		goto free_prog_sec;
2322 
2323 	prog->orig_prog = NULL;
2324 	prog->jited = 0;
2325 
2326 	atomic64_set(&prog->aux->refcnt, 1);
2327 	prog->gpl_compatible = is_gpl ? 1 : 0;
2328 
2329 	if (bpf_prog_is_dev_bound(prog->aux)) {
2330 		err = bpf_prog_offload_init(prog, attr);
2331 		if (err)
2332 			goto free_prog_sec;
2333 	}
2334 
2335 	/* find program type: socket_filter vs tracing_filter */
2336 	err = find_prog_type(type, prog);
2337 	if (err < 0)
2338 		goto free_prog_sec;
2339 
2340 	prog->aux->load_time = ktime_get_boottime_ns();
2341 	err = bpf_obj_name_cpy(prog->aux->name, attr->prog_name,
2342 			       sizeof(attr->prog_name));
2343 	if (err < 0)
2344 		goto free_prog_sec;
2345 
2346 	/* run eBPF verifier */
2347 	err = bpf_check(&prog, attr, uattr);
2348 	if (err < 0)
2349 		goto free_used_maps;
2350 
2351 	prog = bpf_prog_select_runtime(prog, &err);
2352 	if (err < 0)
2353 		goto free_used_maps;
2354 
2355 	err = bpf_prog_alloc_id(prog);
2356 	if (err)
2357 		goto free_used_maps;
2358 
2359 	/* Upon success of bpf_prog_alloc_id(), the BPF prog is
2360 	 * effectively publicly exposed. However, retrieving via
2361 	 * bpf_prog_get_fd_by_id() will take another reference,
2362 	 * therefore it cannot be gone underneath us.
2363 	 *
2364 	 * Only for the time /after/ successful bpf_prog_new_fd()
2365 	 * and before returning to userspace, we might just hold
2366 	 * one reference and any parallel close on that fd could
2367 	 * rip everything out. Hence, below notifications must
2368 	 * happen before bpf_prog_new_fd().
2369 	 *
2370 	 * Also, any failure handling from this point onwards must
2371 	 * be using bpf_prog_put() given the program is exposed.
2372 	 */
2373 	bpf_prog_kallsyms_add(prog);
2374 	perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_LOAD, 0);
2375 	bpf_audit_prog(prog, BPF_AUDIT_LOAD);
2376 
2377 	err = bpf_prog_new_fd(prog);
2378 	if (err < 0)
2379 		bpf_prog_put(prog);
2380 	return err;
2381 
2382 free_used_maps:
2383 	/* In case we have subprogs, we need to wait for a grace
2384 	 * period before we can tear down JIT memory since symbols
2385 	 * are already exposed under kallsyms.
2386 	 */
2387 	__bpf_prog_put_noref(prog, prog->aux->func_cnt);
2388 	return err;
2389 free_prog_sec:
2390 	free_uid(prog->aux->user);
2391 	security_bpf_prog_free(prog->aux);
2392 free_prog:
2393 	if (prog->aux->attach_btf)
2394 		btf_put(prog->aux->attach_btf);
2395 	bpf_prog_free(prog);
2396 	return err;
2397 }
2398 
2399 #define BPF_OBJ_LAST_FIELD file_flags
2400 
2401 static int bpf_obj_pin(const union bpf_attr *attr)
2402 {
2403 	if (CHECK_ATTR(BPF_OBJ) || attr->file_flags != 0)
2404 		return -EINVAL;
2405 
2406 	return bpf_obj_pin_user(attr->bpf_fd, u64_to_user_ptr(attr->pathname));
2407 }
2408 
2409 static int bpf_obj_get(const union bpf_attr *attr)
2410 {
2411 	if (CHECK_ATTR(BPF_OBJ) || attr->bpf_fd != 0 ||
2412 	    attr->file_flags & ~BPF_OBJ_FLAG_MASK)
2413 		return -EINVAL;
2414 
2415 	return bpf_obj_get_user(u64_to_user_ptr(attr->pathname),
2416 				attr->file_flags);
2417 }
2418 
2419 void bpf_link_init(struct bpf_link *link, enum bpf_link_type type,
2420 		   const struct bpf_link_ops *ops, struct bpf_prog *prog)
2421 {
2422 	atomic64_set(&link->refcnt, 1);
2423 	link->type = type;
2424 	link->id = 0;
2425 	link->ops = ops;
2426 	link->prog = prog;
2427 }
2428 
2429 static void bpf_link_free_id(int id)
2430 {
2431 	if (!id)
2432 		return;
2433 
2434 	spin_lock_bh(&link_idr_lock);
2435 	idr_remove(&link_idr, id);
2436 	spin_unlock_bh(&link_idr_lock);
2437 }
2438 
2439 /* Clean up bpf_link and corresponding anon_inode file and FD. After
2440  * anon_inode is created, bpf_link can't be just kfree()'d due to deferred
2441  * anon_inode's release() call. This helper marksbpf_link as
2442  * defunct, releases anon_inode file and puts reserved FD. bpf_prog's refcnt
2443  * is not decremented, it's the responsibility of a calling code that failed
2444  * to complete bpf_link initialization.
2445  */
2446 void bpf_link_cleanup(struct bpf_link_primer *primer)
2447 {
2448 	primer->link->prog = NULL;
2449 	bpf_link_free_id(primer->id);
2450 	fput(primer->file);
2451 	put_unused_fd(primer->fd);
2452 }
2453 
2454 void bpf_link_inc(struct bpf_link *link)
2455 {
2456 	atomic64_inc(&link->refcnt);
2457 }
2458 
2459 /* bpf_link_free is guaranteed to be called from process context */
2460 static void bpf_link_free(struct bpf_link *link)
2461 {
2462 	bpf_link_free_id(link->id);
2463 	if (link->prog) {
2464 		/* detach BPF program, clean up used resources */
2465 		link->ops->release(link);
2466 		bpf_prog_put(link->prog);
2467 	}
2468 	/* free bpf_link and its containing memory */
2469 	link->ops->dealloc(link);
2470 }
2471 
2472 static void bpf_link_put_deferred(struct work_struct *work)
2473 {
2474 	struct bpf_link *link = container_of(work, struct bpf_link, work);
2475 
2476 	bpf_link_free(link);
2477 }
2478 
2479 /* bpf_link_put can be called from atomic context, but ensures that resources
2480  * are freed from process context
2481  */
2482 void bpf_link_put(struct bpf_link *link)
2483 {
2484 	if (!atomic64_dec_and_test(&link->refcnt))
2485 		return;
2486 
2487 	if (in_atomic()) {
2488 		INIT_WORK(&link->work, bpf_link_put_deferred);
2489 		schedule_work(&link->work);
2490 	} else {
2491 		bpf_link_free(link);
2492 	}
2493 }
2494 
2495 static int bpf_link_release(struct inode *inode, struct file *filp)
2496 {
2497 	struct bpf_link *link = filp->private_data;
2498 
2499 	bpf_link_put(link);
2500 	return 0;
2501 }
2502 
2503 #ifdef CONFIG_PROC_FS
2504 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type)
2505 #define BPF_MAP_TYPE(_id, _ops)
2506 #define BPF_LINK_TYPE(_id, _name) [_id] = #_name,
2507 static const char *bpf_link_type_strs[] = {
2508 	[BPF_LINK_TYPE_UNSPEC] = "<invalid>",
2509 #include <linux/bpf_types.h>
2510 };
2511 #undef BPF_PROG_TYPE
2512 #undef BPF_MAP_TYPE
2513 #undef BPF_LINK_TYPE
2514 
2515 static void bpf_link_show_fdinfo(struct seq_file *m, struct file *filp)
2516 {
2517 	const struct bpf_link *link = filp->private_data;
2518 	const struct bpf_prog *prog = link->prog;
2519 	char prog_tag[sizeof(prog->tag) * 2 + 1] = { };
2520 
2521 	bin2hex(prog_tag, prog->tag, sizeof(prog->tag));
2522 	seq_printf(m,
2523 		   "link_type:\t%s\n"
2524 		   "link_id:\t%u\n"
2525 		   "prog_tag:\t%s\n"
2526 		   "prog_id:\t%u\n",
2527 		   bpf_link_type_strs[link->type],
2528 		   link->id,
2529 		   prog_tag,
2530 		   prog->aux->id);
2531 	if (link->ops->show_fdinfo)
2532 		link->ops->show_fdinfo(link, m);
2533 }
2534 #endif
2535 
2536 static const struct file_operations bpf_link_fops = {
2537 #ifdef CONFIG_PROC_FS
2538 	.show_fdinfo	= bpf_link_show_fdinfo,
2539 #endif
2540 	.release	= bpf_link_release,
2541 	.read		= bpf_dummy_read,
2542 	.write		= bpf_dummy_write,
2543 };
2544 
2545 static int bpf_link_alloc_id(struct bpf_link *link)
2546 {
2547 	int id;
2548 
2549 	idr_preload(GFP_KERNEL);
2550 	spin_lock_bh(&link_idr_lock);
2551 	id = idr_alloc_cyclic(&link_idr, link, 1, INT_MAX, GFP_ATOMIC);
2552 	spin_unlock_bh(&link_idr_lock);
2553 	idr_preload_end();
2554 
2555 	return id;
2556 }
2557 
2558 /* Prepare bpf_link to be exposed to user-space by allocating anon_inode file,
2559  * reserving unused FD and allocating ID from link_idr. This is to be paired
2560  * with bpf_link_settle() to install FD and ID and expose bpf_link to
2561  * user-space, if bpf_link is successfully attached. If not, bpf_link and
2562  * pre-allocated resources are to be freed with bpf_cleanup() call. All the
2563  * transient state is passed around in struct bpf_link_primer.
2564  * This is preferred way to create and initialize bpf_link, especially when
2565  * there are complicated and expensive operations inbetween creating bpf_link
2566  * itself and attaching it to BPF hook. By using bpf_link_prime() and
2567  * bpf_link_settle() kernel code using bpf_link doesn't have to perform
2568  * expensive (and potentially failing) roll back operations in a rare case
2569  * that file, FD, or ID can't be allocated.
2570  */
2571 int bpf_link_prime(struct bpf_link *link, struct bpf_link_primer *primer)
2572 {
2573 	struct file *file;
2574 	int fd, id;
2575 
2576 	fd = get_unused_fd_flags(O_CLOEXEC);
2577 	if (fd < 0)
2578 		return fd;
2579 
2580 
2581 	id = bpf_link_alloc_id(link);
2582 	if (id < 0) {
2583 		put_unused_fd(fd);
2584 		return id;
2585 	}
2586 
2587 	file = anon_inode_getfile("bpf_link", &bpf_link_fops, link, O_CLOEXEC);
2588 	if (IS_ERR(file)) {
2589 		bpf_link_free_id(id);
2590 		put_unused_fd(fd);
2591 		return PTR_ERR(file);
2592 	}
2593 
2594 	primer->link = link;
2595 	primer->file = file;
2596 	primer->fd = fd;
2597 	primer->id = id;
2598 	return 0;
2599 }
2600 
2601 int bpf_link_settle(struct bpf_link_primer *primer)
2602 {
2603 	/* make bpf_link fetchable by ID */
2604 	spin_lock_bh(&link_idr_lock);
2605 	primer->link->id = primer->id;
2606 	spin_unlock_bh(&link_idr_lock);
2607 	/* make bpf_link fetchable by FD */
2608 	fd_install(primer->fd, primer->file);
2609 	/* pass through installed FD */
2610 	return primer->fd;
2611 }
2612 
2613 int bpf_link_new_fd(struct bpf_link *link)
2614 {
2615 	return anon_inode_getfd("bpf-link", &bpf_link_fops, link, O_CLOEXEC);
2616 }
2617 
2618 struct bpf_link *bpf_link_get_from_fd(u32 ufd)
2619 {
2620 	struct fd f = fdget(ufd);
2621 	struct bpf_link *link;
2622 
2623 	if (!f.file)
2624 		return ERR_PTR(-EBADF);
2625 	if (f.file->f_op != &bpf_link_fops) {
2626 		fdput(f);
2627 		return ERR_PTR(-EINVAL);
2628 	}
2629 
2630 	link = f.file->private_data;
2631 	bpf_link_inc(link);
2632 	fdput(f);
2633 
2634 	return link;
2635 }
2636 
2637 struct bpf_tracing_link {
2638 	struct bpf_link link;
2639 	enum bpf_attach_type attach_type;
2640 	struct bpf_trampoline *trampoline;
2641 	struct bpf_prog *tgt_prog;
2642 };
2643 
2644 static void bpf_tracing_link_release(struct bpf_link *link)
2645 {
2646 	struct bpf_tracing_link *tr_link =
2647 		container_of(link, struct bpf_tracing_link, link);
2648 
2649 	WARN_ON_ONCE(bpf_trampoline_unlink_prog(link->prog,
2650 						tr_link->trampoline));
2651 
2652 	bpf_trampoline_put(tr_link->trampoline);
2653 
2654 	/* tgt_prog is NULL if target is a kernel function */
2655 	if (tr_link->tgt_prog)
2656 		bpf_prog_put(tr_link->tgt_prog);
2657 }
2658 
2659 static void bpf_tracing_link_dealloc(struct bpf_link *link)
2660 {
2661 	struct bpf_tracing_link *tr_link =
2662 		container_of(link, struct bpf_tracing_link, link);
2663 
2664 	kfree(tr_link);
2665 }
2666 
2667 static void bpf_tracing_link_show_fdinfo(const struct bpf_link *link,
2668 					 struct seq_file *seq)
2669 {
2670 	struct bpf_tracing_link *tr_link =
2671 		container_of(link, struct bpf_tracing_link, link);
2672 
2673 	seq_printf(seq,
2674 		   "attach_type:\t%d\n",
2675 		   tr_link->attach_type);
2676 }
2677 
2678 static int bpf_tracing_link_fill_link_info(const struct bpf_link *link,
2679 					   struct bpf_link_info *info)
2680 {
2681 	struct bpf_tracing_link *tr_link =
2682 		container_of(link, struct bpf_tracing_link, link);
2683 
2684 	info->tracing.attach_type = tr_link->attach_type;
2685 	bpf_trampoline_unpack_key(tr_link->trampoline->key,
2686 				  &info->tracing.target_obj_id,
2687 				  &info->tracing.target_btf_id);
2688 
2689 	return 0;
2690 }
2691 
2692 static const struct bpf_link_ops bpf_tracing_link_lops = {
2693 	.release = bpf_tracing_link_release,
2694 	.dealloc = bpf_tracing_link_dealloc,
2695 	.show_fdinfo = bpf_tracing_link_show_fdinfo,
2696 	.fill_link_info = bpf_tracing_link_fill_link_info,
2697 };
2698 
2699 static int bpf_tracing_prog_attach(struct bpf_prog *prog,
2700 				   int tgt_prog_fd,
2701 				   u32 btf_id)
2702 {
2703 	struct bpf_link_primer link_primer;
2704 	struct bpf_prog *tgt_prog = NULL;
2705 	struct bpf_trampoline *tr = NULL;
2706 	struct bpf_tracing_link *link;
2707 	u64 key = 0;
2708 	int err;
2709 
2710 	switch (prog->type) {
2711 	case BPF_PROG_TYPE_TRACING:
2712 		if (prog->expected_attach_type != BPF_TRACE_FENTRY &&
2713 		    prog->expected_attach_type != BPF_TRACE_FEXIT &&
2714 		    prog->expected_attach_type != BPF_MODIFY_RETURN) {
2715 			err = -EINVAL;
2716 			goto out_put_prog;
2717 		}
2718 		break;
2719 	case BPF_PROG_TYPE_EXT:
2720 		if (prog->expected_attach_type != 0) {
2721 			err = -EINVAL;
2722 			goto out_put_prog;
2723 		}
2724 		break;
2725 	case BPF_PROG_TYPE_LSM:
2726 		if (prog->expected_attach_type != BPF_LSM_MAC) {
2727 			err = -EINVAL;
2728 			goto out_put_prog;
2729 		}
2730 		break;
2731 	default:
2732 		err = -EINVAL;
2733 		goto out_put_prog;
2734 	}
2735 
2736 	if (!!tgt_prog_fd != !!btf_id) {
2737 		err = -EINVAL;
2738 		goto out_put_prog;
2739 	}
2740 
2741 	if (tgt_prog_fd) {
2742 		/* For now we only allow new targets for BPF_PROG_TYPE_EXT */
2743 		if (prog->type != BPF_PROG_TYPE_EXT) {
2744 			err = -EINVAL;
2745 			goto out_put_prog;
2746 		}
2747 
2748 		tgt_prog = bpf_prog_get(tgt_prog_fd);
2749 		if (IS_ERR(tgt_prog)) {
2750 			err = PTR_ERR(tgt_prog);
2751 			tgt_prog = NULL;
2752 			goto out_put_prog;
2753 		}
2754 
2755 		key = bpf_trampoline_compute_key(tgt_prog, NULL, btf_id);
2756 	}
2757 
2758 	link = kzalloc(sizeof(*link), GFP_USER);
2759 	if (!link) {
2760 		err = -ENOMEM;
2761 		goto out_put_prog;
2762 	}
2763 	bpf_link_init(&link->link, BPF_LINK_TYPE_TRACING,
2764 		      &bpf_tracing_link_lops, prog);
2765 	link->attach_type = prog->expected_attach_type;
2766 
2767 	mutex_lock(&prog->aux->dst_mutex);
2768 
2769 	/* There are a few possible cases here:
2770 	 *
2771 	 * - if prog->aux->dst_trampoline is set, the program was just loaded
2772 	 *   and not yet attached to anything, so we can use the values stored
2773 	 *   in prog->aux
2774 	 *
2775 	 * - if prog->aux->dst_trampoline is NULL, the program has already been
2776          *   attached to a target and its initial target was cleared (below)
2777 	 *
2778 	 * - if tgt_prog != NULL, the caller specified tgt_prog_fd +
2779 	 *   target_btf_id using the link_create API.
2780 	 *
2781 	 * - if tgt_prog == NULL when this function was called using the old
2782 	 *   raw_tracepoint_open API, and we need a target from prog->aux
2783 	 *
2784 	 * - if prog->aux->dst_trampoline and tgt_prog is NULL, the program
2785 	 *   was detached and is going for re-attachment.
2786 	 */
2787 	if (!prog->aux->dst_trampoline && !tgt_prog) {
2788 		/*
2789 		 * Allow re-attach for TRACING and LSM programs. If it's
2790 		 * currently linked, bpf_trampoline_link_prog will fail.
2791 		 * EXT programs need to specify tgt_prog_fd, so they
2792 		 * re-attach in separate code path.
2793 		 */
2794 		if (prog->type != BPF_PROG_TYPE_TRACING &&
2795 		    prog->type != BPF_PROG_TYPE_LSM) {
2796 			err = -EINVAL;
2797 			goto out_unlock;
2798 		}
2799 		btf_id = prog->aux->attach_btf_id;
2800 		key = bpf_trampoline_compute_key(NULL, prog->aux->attach_btf, btf_id);
2801 	}
2802 
2803 	if (!prog->aux->dst_trampoline ||
2804 	    (key && key != prog->aux->dst_trampoline->key)) {
2805 		/* If there is no saved target, or the specified target is
2806 		 * different from the destination specified at load time, we
2807 		 * need a new trampoline and a check for compatibility
2808 		 */
2809 		struct bpf_attach_target_info tgt_info = {};
2810 
2811 		err = bpf_check_attach_target(NULL, prog, tgt_prog, btf_id,
2812 					      &tgt_info);
2813 		if (err)
2814 			goto out_unlock;
2815 
2816 		tr = bpf_trampoline_get(key, &tgt_info);
2817 		if (!tr) {
2818 			err = -ENOMEM;
2819 			goto out_unlock;
2820 		}
2821 	} else {
2822 		/* The caller didn't specify a target, or the target was the
2823 		 * same as the destination supplied during program load. This
2824 		 * means we can reuse the trampoline and reference from program
2825 		 * load time, and there is no need to allocate a new one. This
2826 		 * can only happen once for any program, as the saved values in
2827 		 * prog->aux are cleared below.
2828 		 */
2829 		tr = prog->aux->dst_trampoline;
2830 		tgt_prog = prog->aux->dst_prog;
2831 	}
2832 
2833 	err = bpf_link_prime(&link->link, &link_primer);
2834 	if (err)
2835 		goto out_unlock;
2836 
2837 	err = bpf_trampoline_link_prog(prog, tr);
2838 	if (err) {
2839 		bpf_link_cleanup(&link_primer);
2840 		link = NULL;
2841 		goto out_unlock;
2842 	}
2843 
2844 	link->tgt_prog = tgt_prog;
2845 	link->trampoline = tr;
2846 
2847 	/* Always clear the trampoline and target prog from prog->aux to make
2848 	 * sure the original attach destination is not kept alive after a
2849 	 * program is (re-)attached to another target.
2850 	 */
2851 	if (prog->aux->dst_prog &&
2852 	    (tgt_prog_fd || tr != prog->aux->dst_trampoline))
2853 		/* got extra prog ref from syscall, or attaching to different prog */
2854 		bpf_prog_put(prog->aux->dst_prog);
2855 	if (prog->aux->dst_trampoline && tr != prog->aux->dst_trampoline)
2856 		/* we allocated a new trampoline, so free the old one */
2857 		bpf_trampoline_put(prog->aux->dst_trampoline);
2858 
2859 	prog->aux->dst_prog = NULL;
2860 	prog->aux->dst_trampoline = NULL;
2861 	mutex_unlock(&prog->aux->dst_mutex);
2862 
2863 	return bpf_link_settle(&link_primer);
2864 out_unlock:
2865 	if (tr && tr != prog->aux->dst_trampoline)
2866 		bpf_trampoline_put(tr);
2867 	mutex_unlock(&prog->aux->dst_mutex);
2868 	kfree(link);
2869 out_put_prog:
2870 	if (tgt_prog_fd && tgt_prog)
2871 		bpf_prog_put(tgt_prog);
2872 	return err;
2873 }
2874 
2875 struct bpf_raw_tp_link {
2876 	struct bpf_link link;
2877 	struct bpf_raw_event_map *btp;
2878 };
2879 
2880 static void bpf_raw_tp_link_release(struct bpf_link *link)
2881 {
2882 	struct bpf_raw_tp_link *raw_tp =
2883 		container_of(link, struct bpf_raw_tp_link, link);
2884 
2885 	bpf_probe_unregister(raw_tp->btp, raw_tp->link.prog);
2886 	bpf_put_raw_tracepoint(raw_tp->btp);
2887 }
2888 
2889 static void bpf_raw_tp_link_dealloc(struct bpf_link *link)
2890 {
2891 	struct bpf_raw_tp_link *raw_tp =
2892 		container_of(link, struct bpf_raw_tp_link, link);
2893 
2894 	kfree(raw_tp);
2895 }
2896 
2897 static void bpf_raw_tp_link_show_fdinfo(const struct bpf_link *link,
2898 					struct seq_file *seq)
2899 {
2900 	struct bpf_raw_tp_link *raw_tp_link =
2901 		container_of(link, struct bpf_raw_tp_link, link);
2902 
2903 	seq_printf(seq,
2904 		   "tp_name:\t%s\n",
2905 		   raw_tp_link->btp->tp->name);
2906 }
2907 
2908 static int bpf_raw_tp_link_fill_link_info(const struct bpf_link *link,
2909 					  struct bpf_link_info *info)
2910 {
2911 	struct bpf_raw_tp_link *raw_tp_link =
2912 		container_of(link, struct bpf_raw_tp_link, link);
2913 	char __user *ubuf = u64_to_user_ptr(info->raw_tracepoint.tp_name);
2914 	const char *tp_name = raw_tp_link->btp->tp->name;
2915 	u32 ulen = info->raw_tracepoint.tp_name_len;
2916 	size_t tp_len = strlen(tp_name);
2917 
2918 	if (!ulen ^ !ubuf)
2919 		return -EINVAL;
2920 
2921 	info->raw_tracepoint.tp_name_len = tp_len + 1;
2922 
2923 	if (!ubuf)
2924 		return 0;
2925 
2926 	if (ulen >= tp_len + 1) {
2927 		if (copy_to_user(ubuf, tp_name, tp_len + 1))
2928 			return -EFAULT;
2929 	} else {
2930 		char zero = '\0';
2931 
2932 		if (copy_to_user(ubuf, tp_name, ulen - 1))
2933 			return -EFAULT;
2934 		if (put_user(zero, ubuf + ulen - 1))
2935 			return -EFAULT;
2936 		return -ENOSPC;
2937 	}
2938 
2939 	return 0;
2940 }
2941 
2942 static const struct bpf_link_ops bpf_raw_tp_link_lops = {
2943 	.release = bpf_raw_tp_link_release,
2944 	.dealloc = bpf_raw_tp_link_dealloc,
2945 	.show_fdinfo = bpf_raw_tp_link_show_fdinfo,
2946 	.fill_link_info = bpf_raw_tp_link_fill_link_info,
2947 };
2948 
2949 #ifdef CONFIG_PERF_EVENTS
2950 struct bpf_perf_link {
2951 	struct bpf_link link;
2952 	struct file *perf_file;
2953 };
2954 
2955 static void bpf_perf_link_release(struct bpf_link *link)
2956 {
2957 	struct bpf_perf_link *perf_link = container_of(link, struct bpf_perf_link, link);
2958 	struct perf_event *event = perf_link->perf_file->private_data;
2959 
2960 	perf_event_free_bpf_prog(event);
2961 	fput(perf_link->perf_file);
2962 }
2963 
2964 static void bpf_perf_link_dealloc(struct bpf_link *link)
2965 {
2966 	struct bpf_perf_link *perf_link = container_of(link, struct bpf_perf_link, link);
2967 
2968 	kfree(perf_link);
2969 }
2970 
2971 static const struct bpf_link_ops bpf_perf_link_lops = {
2972 	.release = bpf_perf_link_release,
2973 	.dealloc = bpf_perf_link_dealloc,
2974 };
2975 
2976 static int bpf_perf_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
2977 {
2978 	struct bpf_link_primer link_primer;
2979 	struct bpf_perf_link *link;
2980 	struct perf_event *event;
2981 	struct file *perf_file;
2982 	int err;
2983 
2984 	if (attr->link_create.flags)
2985 		return -EINVAL;
2986 
2987 	perf_file = perf_event_get(attr->link_create.target_fd);
2988 	if (IS_ERR(perf_file))
2989 		return PTR_ERR(perf_file);
2990 
2991 	link = kzalloc(sizeof(*link), GFP_USER);
2992 	if (!link) {
2993 		err = -ENOMEM;
2994 		goto out_put_file;
2995 	}
2996 	bpf_link_init(&link->link, BPF_LINK_TYPE_PERF_EVENT, &bpf_perf_link_lops, prog);
2997 	link->perf_file = perf_file;
2998 
2999 	err = bpf_link_prime(&link->link, &link_primer);
3000 	if (err) {
3001 		kfree(link);
3002 		goto out_put_file;
3003 	}
3004 
3005 	event = perf_file->private_data;
3006 	err = perf_event_set_bpf_prog(event, prog, attr->link_create.perf_event.bpf_cookie);
3007 	if (err) {
3008 		bpf_link_cleanup(&link_primer);
3009 		goto out_put_file;
3010 	}
3011 	/* perf_event_set_bpf_prog() doesn't take its own refcnt on prog */
3012 	bpf_prog_inc(prog);
3013 
3014 	return bpf_link_settle(&link_primer);
3015 
3016 out_put_file:
3017 	fput(perf_file);
3018 	return err;
3019 }
3020 #endif /* CONFIG_PERF_EVENTS */
3021 
3022 #define BPF_RAW_TRACEPOINT_OPEN_LAST_FIELD raw_tracepoint.prog_fd
3023 
3024 static int bpf_raw_tracepoint_open(const union bpf_attr *attr)
3025 {
3026 	struct bpf_link_primer link_primer;
3027 	struct bpf_raw_tp_link *link;
3028 	struct bpf_raw_event_map *btp;
3029 	struct bpf_prog *prog;
3030 	const char *tp_name;
3031 	char buf[128];
3032 	int err;
3033 
3034 	if (CHECK_ATTR(BPF_RAW_TRACEPOINT_OPEN))
3035 		return -EINVAL;
3036 
3037 	prog = bpf_prog_get(attr->raw_tracepoint.prog_fd);
3038 	if (IS_ERR(prog))
3039 		return PTR_ERR(prog);
3040 
3041 	switch (prog->type) {
3042 	case BPF_PROG_TYPE_TRACING:
3043 	case BPF_PROG_TYPE_EXT:
3044 	case BPF_PROG_TYPE_LSM:
3045 		if (attr->raw_tracepoint.name) {
3046 			/* The attach point for this category of programs
3047 			 * should be specified via btf_id during program load.
3048 			 */
3049 			err = -EINVAL;
3050 			goto out_put_prog;
3051 		}
3052 		if (prog->type == BPF_PROG_TYPE_TRACING &&
3053 		    prog->expected_attach_type == BPF_TRACE_RAW_TP) {
3054 			tp_name = prog->aux->attach_func_name;
3055 			break;
3056 		}
3057 		err = bpf_tracing_prog_attach(prog, 0, 0);
3058 		if (err >= 0)
3059 			return err;
3060 		goto out_put_prog;
3061 	case BPF_PROG_TYPE_RAW_TRACEPOINT:
3062 	case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE:
3063 		if (strncpy_from_user(buf,
3064 				      u64_to_user_ptr(attr->raw_tracepoint.name),
3065 				      sizeof(buf) - 1) < 0) {
3066 			err = -EFAULT;
3067 			goto out_put_prog;
3068 		}
3069 		buf[sizeof(buf) - 1] = 0;
3070 		tp_name = buf;
3071 		break;
3072 	default:
3073 		err = -EINVAL;
3074 		goto out_put_prog;
3075 	}
3076 
3077 	btp = bpf_get_raw_tracepoint(tp_name);
3078 	if (!btp) {
3079 		err = -ENOENT;
3080 		goto out_put_prog;
3081 	}
3082 
3083 	link = kzalloc(sizeof(*link), GFP_USER);
3084 	if (!link) {
3085 		err = -ENOMEM;
3086 		goto out_put_btp;
3087 	}
3088 	bpf_link_init(&link->link, BPF_LINK_TYPE_RAW_TRACEPOINT,
3089 		      &bpf_raw_tp_link_lops, prog);
3090 	link->btp = btp;
3091 
3092 	err = bpf_link_prime(&link->link, &link_primer);
3093 	if (err) {
3094 		kfree(link);
3095 		goto out_put_btp;
3096 	}
3097 
3098 	err = bpf_probe_register(link->btp, prog);
3099 	if (err) {
3100 		bpf_link_cleanup(&link_primer);
3101 		goto out_put_btp;
3102 	}
3103 
3104 	return bpf_link_settle(&link_primer);
3105 
3106 out_put_btp:
3107 	bpf_put_raw_tracepoint(btp);
3108 out_put_prog:
3109 	bpf_prog_put(prog);
3110 	return err;
3111 }
3112 
3113 static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog,
3114 					     enum bpf_attach_type attach_type)
3115 {
3116 	switch (prog->type) {
3117 	case BPF_PROG_TYPE_CGROUP_SOCK:
3118 	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
3119 	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
3120 	case BPF_PROG_TYPE_SK_LOOKUP:
3121 		return attach_type == prog->expected_attach_type ? 0 : -EINVAL;
3122 	case BPF_PROG_TYPE_CGROUP_SKB:
3123 		if (!capable(CAP_NET_ADMIN))
3124 			/* cg-skb progs can be loaded by unpriv user.
3125 			 * check permissions at attach time.
3126 			 */
3127 			return -EPERM;
3128 		return prog->enforce_expected_attach_type &&
3129 			prog->expected_attach_type != attach_type ?
3130 			-EINVAL : 0;
3131 	default:
3132 		return 0;
3133 	}
3134 }
3135 
3136 static enum bpf_prog_type
3137 attach_type_to_prog_type(enum bpf_attach_type attach_type)
3138 {
3139 	switch (attach_type) {
3140 	case BPF_CGROUP_INET_INGRESS:
3141 	case BPF_CGROUP_INET_EGRESS:
3142 		return BPF_PROG_TYPE_CGROUP_SKB;
3143 	case BPF_CGROUP_INET_SOCK_CREATE:
3144 	case BPF_CGROUP_INET_SOCK_RELEASE:
3145 	case BPF_CGROUP_INET4_POST_BIND:
3146 	case BPF_CGROUP_INET6_POST_BIND:
3147 		return BPF_PROG_TYPE_CGROUP_SOCK;
3148 	case BPF_CGROUP_INET4_BIND:
3149 	case BPF_CGROUP_INET6_BIND:
3150 	case BPF_CGROUP_INET4_CONNECT:
3151 	case BPF_CGROUP_INET6_CONNECT:
3152 	case BPF_CGROUP_INET4_GETPEERNAME:
3153 	case BPF_CGROUP_INET6_GETPEERNAME:
3154 	case BPF_CGROUP_INET4_GETSOCKNAME:
3155 	case BPF_CGROUP_INET6_GETSOCKNAME:
3156 	case BPF_CGROUP_UDP4_SENDMSG:
3157 	case BPF_CGROUP_UDP6_SENDMSG:
3158 	case BPF_CGROUP_UDP4_RECVMSG:
3159 	case BPF_CGROUP_UDP6_RECVMSG:
3160 		return BPF_PROG_TYPE_CGROUP_SOCK_ADDR;
3161 	case BPF_CGROUP_SOCK_OPS:
3162 		return BPF_PROG_TYPE_SOCK_OPS;
3163 	case BPF_CGROUP_DEVICE:
3164 		return BPF_PROG_TYPE_CGROUP_DEVICE;
3165 	case BPF_SK_MSG_VERDICT:
3166 		return BPF_PROG_TYPE_SK_MSG;
3167 	case BPF_SK_SKB_STREAM_PARSER:
3168 	case BPF_SK_SKB_STREAM_VERDICT:
3169 	case BPF_SK_SKB_VERDICT:
3170 		return BPF_PROG_TYPE_SK_SKB;
3171 	case BPF_LIRC_MODE2:
3172 		return BPF_PROG_TYPE_LIRC_MODE2;
3173 	case BPF_FLOW_DISSECTOR:
3174 		return BPF_PROG_TYPE_FLOW_DISSECTOR;
3175 	case BPF_CGROUP_SYSCTL:
3176 		return BPF_PROG_TYPE_CGROUP_SYSCTL;
3177 	case BPF_CGROUP_GETSOCKOPT:
3178 	case BPF_CGROUP_SETSOCKOPT:
3179 		return BPF_PROG_TYPE_CGROUP_SOCKOPT;
3180 	case BPF_TRACE_ITER:
3181 		return BPF_PROG_TYPE_TRACING;
3182 	case BPF_SK_LOOKUP:
3183 		return BPF_PROG_TYPE_SK_LOOKUP;
3184 	case BPF_XDP:
3185 		return BPF_PROG_TYPE_XDP;
3186 	default:
3187 		return BPF_PROG_TYPE_UNSPEC;
3188 	}
3189 }
3190 
3191 #define BPF_PROG_ATTACH_LAST_FIELD replace_bpf_fd
3192 
3193 #define BPF_F_ATTACH_MASK \
3194 	(BPF_F_ALLOW_OVERRIDE | BPF_F_ALLOW_MULTI | BPF_F_REPLACE)
3195 
3196 static int bpf_prog_attach(const union bpf_attr *attr)
3197 {
3198 	enum bpf_prog_type ptype;
3199 	struct bpf_prog *prog;
3200 	int ret;
3201 
3202 	if (CHECK_ATTR(BPF_PROG_ATTACH))
3203 		return -EINVAL;
3204 
3205 	if (attr->attach_flags & ~BPF_F_ATTACH_MASK)
3206 		return -EINVAL;
3207 
3208 	ptype = attach_type_to_prog_type(attr->attach_type);
3209 	if (ptype == BPF_PROG_TYPE_UNSPEC)
3210 		return -EINVAL;
3211 
3212 	prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype);
3213 	if (IS_ERR(prog))
3214 		return PTR_ERR(prog);
3215 
3216 	if (bpf_prog_attach_check_attach_type(prog, attr->attach_type)) {
3217 		bpf_prog_put(prog);
3218 		return -EINVAL;
3219 	}
3220 
3221 	switch (ptype) {
3222 	case BPF_PROG_TYPE_SK_SKB:
3223 	case BPF_PROG_TYPE_SK_MSG:
3224 		ret = sock_map_get_from_fd(attr, prog);
3225 		break;
3226 	case BPF_PROG_TYPE_LIRC_MODE2:
3227 		ret = lirc_prog_attach(attr, prog);
3228 		break;
3229 	case BPF_PROG_TYPE_FLOW_DISSECTOR:
3230 		ret = netns_bpf_prog_attach(attr, prog);
3231 		break;
3232 	case BPF_PROG_TYPE_CGROUP_DEVICE:
3233 	case BPF_PROG_TYPE_CGROUP_SKB:
3234 	case BPF_PROG_TYPE_CGROUP_SOCK:
3235 	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
3236 	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
3237 	case BPF_PROG_TYPE_CGROUP_SYSCTL:
3238 	case BPF_PROG_TYPE_SOCK_OPS:
3239 		ret = cgroup_bpf_prog_attach(attr, ptype, prog);
3240 		break;
3241 	default:
3242 		ret = -EINVAL;
3243 	}
3244 
3245 	if (ret)
3246 		bpf_prog_put(prog);
3247 	return ret;
3248 }
3249 
3250 #define BPF_PROG_DETACH_LAST_FIELD attach_type
3251 
3252 static int bpf_prog_detach(const union bpf_attr *attr)
3253 {
3254 	enum bpf_prog_type ptype;
3255 
3256 	if (CHECK_ATTR(BPF_PROG_DETACH))
3257 		return -EINVAL;
3258 
3259 	ptype = attach_type_to_prog_type(attr->attach_type);
3260 
3261 	switch (ptype) {
3262 	case BPF_PROG_TYPE_SK_MSG:
3263 	case BPF_PROG_TYPE_SK_SKB:
3264 		return sock_map_prog_detach(attr, ptype);
3265 	case BPF_PROG_TYPE_LIRC_MODE2:
3266 		return lirc_prog_detach(attr);
3267 	case BPF_PROG_TYPE_FLOW_DISSECTOR:
3268 		return netns_bpf_prog_detach(attr, ptype);
3269 	case BPF_PROG_TYPE_CGROUP_DEVICE:
3270 	case BPF_PROG_TYPE_CGROUP_SKB:
3271 	case BPF_PROG_TYPE_CGROUP_SOCK:
3272 	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
3273 	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
3274 	case BPF_PROG_TYPE_CGROUP_SYSCTL:
3275 	case BPF_PROG_TYPE_SOCK_OPS:
3276 		return cgroup_bpf_prog_detach(attr, ptype);
3277 	default:
3278 		return -EINVAL;
3279 	}
3280 }
3281 
3282 #define BPF_PROG_QUERY_LAST_FIELD query.prog_cnt
3283 
3284 static int bpf_prog_query(const union bpf_attr *attr,
3285 			  union bpf_attr __user *uattr)
3286 {
3287 	if (!capable(CAP_NET_ADMIN))
3288 		return -EPERM;
3289 	if (CHECK_ATTR(BPF_PROG_QUERY))
3290 		return -EINVAL;
3291 	if (attr->query.query_flags & ~BPF_F_QUERY_EFFECTIVE)
3292 		return -EINVAL;
3293 
3294 	switch (attr->query.attach_type) {
3295 	case BPF_CGROUP_INET_INGRESS:
3296 	case BPF_CGROUP_INET_EGRESS:
3297 	case BPF_CGROUP_INET_SOCK_CREATE:
3298 	case BPF_CGROUP_INET_SOCK_RELEASE:
3299 	case BPF_CGROUP_INET4_BIND:
3300 	case BPF_CGROUP_INET6_BIND:
3301 	case BPF_CGROUP_INET4_POST_BIND:
3302 	case BPF_CGROUP_INET6_POST_BIND:
3303 	case BPF_CGROUP_INET4_CONNECT:
3304 	case BPF_CGROUP_INET6_CONNECT:
3305 	case BPF_CGROUP_INET4_GETPEERNAME:
3306 	case BPF_CGROUP_INET6_GETPEERNAME:
3307 	case BPF_CGROUP_INET4_GETSOCKNAME:
3308 	case BPF_CGROUP_INET6_GETSOCKNAME:
3309 	case BPF_CGROUP_UDP4_SENDMSG:
3310 	case BPF_CGROUP_UDP6_SENDMSG:
3311 	case BPF_CGROUP_UDP4_RECVMSG:
3312 	case BPF_CGROUP_UDP6_RECVMSG:
3313 	case BPF_CGROUP_SOCK_OPS:
3314 	case BPF_CGROUP_DEVICE:
3315 	case BPF_CGROUP_SYSCTL:
3316 	case BPF_CGROUP_GETSOCKOPT:
3317 	case BPF_CGROUP_SETSOCKOPT:
3318 		return cgroup_bpf_prog_query(attr, uattr);
3319 	case BPF_LIRC_MODE2:
3320 		return lirc_prog_query(attr, uattr);
3321 	case BPF_FLOW_DISSECTOR:
3322 	case BPF_SK_LOOKUP:
3323 		return netns_bpf_prog_query(attr, uattr);
3324 	default:
3325 		return -EINVAL;
3326 	}
3327 }
3328 
3329 #define BPF_PROG_TEST_RUN_LAST_FIELD test.cpu
3330 
3331 static int bpf_prog_test_run(const union bpf_attr *attr,
3332 			     union bpf_attr __user *uattr)
3333 {
3334 	struct bpf_prog *prog;
3335 	int ret = -ENOTSUPP;
3336 
3337 	if (CHECK_ATTR(BPF_PROG_TEST_RUN))
3338 		return -EINVAL;
3339 
3340 	if ((attr->test.ctx_size_in && !attr->test.ctx_in) ||
3341 	    (!attr->test.ctx_size_in && attr->test.ctx_in))
3342 		return -EINVAL;
3343 
3344 	if ((attr->test.ctx_size_out && !attr->test.ctx_out) ||
3345 	    (!attr->test.ctx_size_out && attr->test.ctx_out))
3346 		return -EINVAL;
3347 
3348 	prog = bpf_prog_get(attr->test.prog_fd);
3349 	if (IS_ERR(prog))
3350 		return PTR_ERR(prog);
3351 
3352 	if (prog->aux->ops->test_run)
3353 		ret = prog->aux->ops->test_run(prog, attr, uattr);
3354 
3355 	bpf_prog_put(prog);
3356 	return ret;
3357 }
3358 
3359 #define BPF_OBJ_GET_NEXT_ID_LAST_FIELD next_id
3360 
3361 static int bpf_obj_get_next_id(const union bpf_attr *attr,
3362 			       union bpf_attr __user *uattr,
3363 			       struct idr *idr,
3364 			       spinlock_t *lock)
3365 {
3366 	u32 next_id = attr->start_id;
3367 	int err = 0;
3368 
3369 	if (CHECK_ATTR(BPF_OBJ_GET_NEXT_ID) || next_id >= INT_MAX)
3370 		return -EINVAL;
3371 
3372 	if (!capable(CAP_SYS_ADMIN))
3373 		return -EPERM;
3374 
3375 	next_id++;
3376 	spin_lock_bh(lock);
3377 	if (!idr_get_next(idr, &next_id))
3378 		err = -ENOENT;
3379 	spin_unlock_bh(lock);
3380 
3381 	if (!err)
3382 		err = put_user(next_id, &uattr->next_id);
3383 
3384 	return err;
3385 }
3386 
3387 struct bpf_map *bpf_map_get_curr_or_next(u32 *id)
3388 {
3389 	struct bpf_map *map;
3390 
3391 	spin_lock_bh(&map_idr_lock);
3392 again:
3393 	map = idr_get_next(&map_idr, id);
3394 	if (map) {
3395 		map = __bpf_map_inc_not_zero(map, false);
3396 		if (IS_ERR(map)) {
3397 			(*id)++;
3398 			goto again;
3399 		}
3400 	}
3401 	spin_unlock_bh(&map_idr_lock);
3402 
3403 	return map;
3404 }
3405 
3406 struct bpf_prog *bpf_prog_get_curr_or_next(u32 *id)
3407 {
3408 	struct bpf_prog *prog;
3409 
3410 	spin_lock_bh(&prog_idr_lock);
3411 again:
3412 	prog = idr_get_next(&prog_idr, id);
3413 	if (prog) {
3414 		prog = bpf_prog_inc_not_zero(prog);
3415 		if (IS_ERR(prog)) {
3416 			(*id)++;
3417 			goto again;
3418 		}
3419 	}
3420 	spin_unlock_bh(&prog_idr_lock);
3421 
3422 	return prog;
3423 }
3424 
3425 #define BPF_PROG_GET_FD_BY_ID_LAST_FIELD prog_id
3426 
3427 struct bpf_prog *bpf_prog_by_id(u32 id)
3428 {
3429 	struct bpf_prog *prog;
3430 
3431 	if (!id)
3432 		return ERR_PTR(-ENOENT);
3433 
3434 	spin_lock_bh(&prog_idr_lock);
3435 	prog = idr_find(&prog_idr, id);
3436 	if (prog)
3437 		prog = bpf_prog_inc_not_zero(prog);
3438 	else
3439 		prog = ERR_PTR(-ENOENT);
3440 	spin_unlock_bh(&prog_idr_lock);
3441 	return prog;
3442 }
3443 
3444 static int bpf_prog_get_fd_by_id(const union bpf_attr *attr)
3445 {
3446 	struct bpf_prog *prog;
3447 	u32 id = attr->prog_id;
3448 	int fd;
3449 
3450 	if (CHECK_ATTR(BPF_PROG_GET_FD_BY_ID))
3451 		return -EINVAL;
3452 
3453 	if (!capable(CAP_SYS_ADMIN))
3454 		return -EPERM;
3455 
3456 	prog = bpf_prog_by_id(id);
3457 	if (IS_ERR(prog))
3458 		return PTR_ERR(prog);
3459 
3460 	fd = bpf_prog_new_fd(prog);
3461 	if (fd < 0)
3462 		bpf_prog_put(prog);
3463 
3464 	return fd;
3465 }
3466 
3467 #define BPF_MAP_GET_FD_BY_ID_LAST_FIELD open_flags
3468 
3469 static int bpf_map_get_fd_by_id(const union bpf_attr *attr)
3470 {
3471 	struct bpf_map *map;
3472 	u32 id = attr->map_id;
3473 	int f_flags;
3474 	int fd;
3475 
3476 	if (CHECK_ATTR(BPF_MAP_GET_FD_BY_ID) ||
3477 	    attr->open_flags & ~BPF_OBJ_FLAG_MASK)
3478 		return -EINVAL;
3479 
3480 	if (!capable(CAP_SYS_ADMIN))
3481 		return -EPERM;
3482 
3483 	f_flags = bpf_get_file_flag(attr->open_flags);
3484 	if (f_flags < 0)
3485 		return f_flags;
3486 
3487 	spin_lock_bh(&map_idr_lock);
3488 	map = idr_find(&map_idr, id);
3489 	if (map)
3490 		map = __bpf_map_inc_not_zero(map, true);
3491 	else
3492 		map = ERR_PTR(-ENOENT);
3493 	spin_unlock_bh(&map_idr_lock);
3494 
3495 	if (IS_ERR(map))
3496 		return PTR_ERR(map);
3497 
3498 	fd = bpf_map_new_fd(map, f_flags);
3499 	if (fd < 0)
3500 		bpf_map_put_with_uref(map);
3501 
3502 	return fd;
3503 }
3504 
3505 static const struct bpf_map *bpf_map_from_imm(const struct bpf_prog *prog,
3506 					      unsigned long addr, u32 *off,
3507 					      u32 *type)
3508 {
3509 	const struct bpf_map *map;
3510 	int i;
3511 
3512 	mutex_lock(&prog->aux->used_maps_mutex);
3513 	for (i = 0, *off = 0; i < prog->aux->used_map_cnt; i++) {
3514 		map = prog->aux->used_maps[i];
3515 		if (map == (void *)addr) {
3516 			*type = BPF_PSEUDO_MAP_FD;
3517 			goto out;
3518 		}
3519 		if (!map->ops->map_direct_value_meta)
3520 			continue;
3521 		if (!map->ops->map_direct_value_meta(map, addr, off)) {
3522 			*type = BPF_PSEUDO_MAP_VALUE;
3523 			goto out;
3524 		}
3525 	}
3526 	map = NULL;
3527 
3528 out:
3529 	mutex_unlock(&prog->aux->used_maps_mutex);
3530 	return map;
3531 }
3532 
3533 static struct bpf_insn *bpf_insn_prepare_dump(const struct bpf_prog *prog,
3534 					      const struct cred *f_cred)
3535 {
3536 	const struct bpf_map *map;
3537 	struct bpf_insn *insns;
3538 	u32 off, type;
3539 	u64 imm;
3540 	u8 code;
3541 	int i;
3542 
3543 	insns = kmemdup(prog->insnsi, bpf_prog_insn_size(prog),
3544 			GFP_USER);
3545 	if (!insns)
3546 		return insns;
3547 
3548 	for (i = 0; i < prog->len; i++) {
3549 		code = insns[i].code;
3550 
3551 		if (code == (BPF_JMP | BPF_TAIL_CALL)) {
3552 			insns[i].code = BPF_JMP | BPF_CALL;
3553 			insns[i].imm = BPF_FUNC_tail_call;
3554 			/* fall-through */
3555 		}
3556 		if (code == (BPF_JMP | BPF_CALL) ||
3557 		    code == (BPF_JMP | BPF_CALL_ARGS)) {
3558 			if (code == (BPF_JMP | BPF_CALL_ARGS))
3559 				insns[i].code = BPF_JMP | BPF_CALL;
3560 			if (!bpf_dump_raw_ok(f_cred))
3561 				insns[i].imm = 0;
3562 			continue;
3563 		}
3564 		if (BPF_CLASS(code) == BPF_LDX && BPF_MODE(code) == BPF_PROBE_MEM) {
3565 			insns[i].code = BPF_LDX | BPF_SIZE(code) | BPF_MEM;
3566 			continue;
3567 		}
3568 
3569 		if (code != (BPF_LD | BPF_IMM | BPF_DW))
3570 			continue;
3571 
3572 		imm = ((u64)insns[i + 1].imm << 32) | (u32)insns[i].imm;
3573 		map = bpf_map_from_imm(prog, imm, &off, &type);
3574 		if (map) {
3575 			insns[i].src_reg = type;
3576 			insns[i].imm = map->id;
3577 			insns[i + 1].imm = off;
3578 			continue;
3579 		}
3580 	}
3581 
3582 	return insns;
3583 }
3584 
3585 static int set_info_rec_size(struct bpf_prog_info *info)
3586 {
3587 	/*
3588 	 * Ensure info.*_rec_size is the same as kernel expected size
3589 	 *
3590 	 * or
3591 	 *
3592 	 * Only allow zero *_rec_size if both _rec_size and _cnt are
3593 	 * zero.  In this case, the kernel will set the expected
3594 	 * _rec_size back to the info.
3595 	 */
3596 
3597 	if ((info->nr_func_info || info->func_info_rec_size) &&
3598 	    info->func_info_rec_size != sizeof(struct bpf_func_info))
3599 		return -EINVAL;
3600 
3601 	if ((info->nr_line_info || info->line_info_rec_size) &&
3602 	    info->line_info_rec_size != sizeof(struct bpf_line_info))
3603 		return -EINVAL;
3604 
3605 	if ((info->nr_jited_line_info || info->jited_line_info_rec_size) &&
3606 	    info->jited_line_info_rec_size != sizeof(__u64))
3607 		return -EINVAL;
3608 
3609 	info->func_info_rec_size = sizeof(struct bpf_func_info);
3610 	info->line_info_rec_size = sizeof(struct bpf_line_info);
3611 	info->jited_line_info_rec_size = sizeof(__u64);
3612 
3613 	return 0;
3614 }
3615 
3616 static int bpf_prog_get_info_by_fd(struct file *file,
3617 				   struct bpf_prog *prog,
3618 				   const union bpf_attr *attr,
3619 				   union bpf_attr __user *uattr)
3620 {
3621 	struct bpf_prog_info __user *uinfo = u64_to_user_ptr(attr->info.info);
3622 	struct bpf_prog_info info;
3623 	u32 info_len = attr->info.info_len;
3624 	struct bpf_prog_kstats stats;
3625 	char __user *uinsns;
3626 	u32 ulen;
3627 	int err;
3628 
3629 	err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len);
3630 	if (err)
3631 		return err;
3632 	info_len = min_t(u32, sizeof(info), info_len);
3633 
3634 	memset(&info, 0, sizeof(info));
3635 	if (copy_from_user(&info, uinfo, info_len))
3636 		return -EFAULT;
3637 
3638 	info.type = prog->type;
3639 	info.id = prog->aux->id;
3640 	info.load_time = prog->aux->load_time;
3641 	info.created_by_uid = from_kuid_munged(current_user_ns(),
3642 					       prog->aux->user->uid);
3643 	info.gpl_compatible = prog->gpl_compatible;
3644 
3645 	memcpy(info.tag, prog->tag, sizeof(prog->tag));
3646 	memcpy(info.name, prog->aux->name, sizeof(prog->aux->name));
3647 
3648 	mutex_lock(&prog->aux->used_maps_mutex);
3649 	ulen = info.nr_map_ids;
3650 	info.nr_map_ids = prog->aux->used_map_cnt;
3651 	ulen = min_t(u32, info.nr_map_ids, ulen);
3652 	if (ulen) {
3653 		u32 __user *user_map_ids = u64_to_user_ptr(info.map_ids);
3654 		u32 i;
3655 
3656 		for (i = 0; i < ulen; i++)
3657 			if (put_user(prog->aux->used_maps[i]->id,
3658 				     &user_map_ids[i])) {
3659 				mutex_unlock(&prog->aux->used_maps_mutex);
3660 				return -EFAULT;
3661 			}
3662 	}
3663 	mutex_unlock(&prog->aux->used_maps_mutex);
3664 
3665 	err = set_info_rec_size(&info);
3666 	if (err)
3667 		return err;
3668 
3669 	bpf_prog_get_stats(prog, &stats);
3670 	info.run_time_ns = stats.nsecs;
3671 	info.run_cnt = stats.cnt;
3672 	info.recursion_misses = stats.misses;
3673 
3674 	info.verified_insns = prog->aux->verified_insns;
3675 
3676 	if (!bpf_capable()) {
3677 		info.jited_prog_len = 0;
3678 		info.xlated_prog_len = 0;
3679 		info.nr_jited_ksyms = 0;
3680 		info.nr_jited_func_lens = 0;
3681 		info.nr_func_info = 0;
3682 		info.nr_line_info = 0;
3683 		info.nr_jited_line_info = 0;
3684 		goto done;
3685 	}
3686 
3687 	ulen = info.xlated_prog_len;
3688 	info.xlated_prog_len = bpf_prog_insn_size(prog);
3689 	if (info.xlated_prog_len && ulen) {
3690 		struct bpf_insn *insns_sanitized;
3691 		bool fault;
3692 
3693 		if (prog->blinded && !bpf_dump_raw_ok(file->f_cred)) {
3694 			info.xlated_prog_insns = 0;
3695 			goto done;
3696 		}
3697 		insns_sanitized = bpf_insn_prepare_dump(prog, file->f_cred);
3698 		if (!insns_sanitized)
3699 			return -ENOMEM;
3700 		uinsns = u64_to_user_ptr(info.xlated_prog_insns);
3701 		ulen = min_t(u32, info.xlated_prog_len, ulen);
3702 		fault = copy_to_user(uinsns, insns_sanitized, ulen);
3703 		kfree(insns_sanitized);
3704 		if (fault)
3705 			return -EFAULT;
3706 	}
3707 
3708 	if (bpf_prog_is_dev_bound(prog->aux)) {
3709 		err = bpf_prog_offload_info_fill(&info, prog);
3710 		if (err)
3711 			return err;
3712 		goto done;
3713 	}
3714 
3715 	/* NOTE: the following code is supposed to be skipped for offload.
3716 	 * bpf_prog_offload_info_fill() is the place to fill similar fields
3717 	 * for offload.
3718 	 */
3719 	ulen = info.jited_prog_len;
3720 	if (prog->aux->func_cnt) {
3721 		u32 i;
3722 
3723 		info.jited_prog_len = 0;
3724 		for (i = 0; i < prog->aux->func_cnt; i++)
3725 			info.jited_prog_len += prog->aux->func[i]->jited_len;
3726 	} else {
3727 		info.jited_prog_len = prog->jited_len;
3728 	}
3729 
3730 	if (info.jited_prog_len && ulen) {
3731 		if (bpf_dump_raw_ok(file->f_cred)) {
3732 			uinsns = u64_to_user_ptr(info.jited_prog_insns);
3733 			ulen = min_t(u32, info.jited_prog_len, ulen);
3734 
3735 			/* for multi-function programs, copy the JITed
3736 			 * instructions for all the functions
3737 			 */
3738 			if (prog->aux->func_cnt) {
3739 				u32 len, free, i;
3740 				u8 *img;
3741 
3742 				free = ulen;
3743 				for (i = 0; i < prog->aux->func_cnt; i++) {
3744 					len = prog->aux->func[i]->jited_len;
3745 					len = min_t(u32, len, free);
3746 					img = (u8 *) prog->aux->func[i]->bpf_func;
3747 					if (copy_to_user(uinsns, img, len))
3748 						return -EFAULT;
3749 					uinsns += len;
3750 					free -= len;
3751 					if (!free)
3752 						break;
3753 				}
3754 			} else {
3755 				if (copy_to_user(uinsns, prog->bpf_func, ulen))
3756 					return -EFAULT;
3757 			}
3758 		} else {
3759 			info.jited_prog_insns = 0;
3760 		}
3761 	}
3762 
3763 	ulen = info.nr_jited_ksyms;
3764 	info.nr_jited_ksyms = prog->aux->func_cnt ? : 1;
3765 	if (ulen) {
3766 		if (bpf_dump_raw_ok(file->f_cred)) {
3767 			unsigned long ksym_addr;
3768 			u64 __user *user_ksyms;
3769 			u32 i;
3770 
3771 			/* copy the address of the kernel symbol
3772 			 * corresponding to each function
3773 			 */
3774 			ulen = min_t(u32, info.nr_jited_ksyms, ulen);
3775 			user_ksyms = u64_to_user_ptr(info.jited_ksyms);
3776 			if (prog->aux->func_cnt) {
3777 				for (i = 0; i < ulen; i++) {
3778 					ksym_addr = (unsigned long)
3779 						prog->aux->func[i]->bpf_func;
3780 					if (put_user((u64) ksym_addr,
3781 						     &user_ksyms[i]))
3782 						return -EFAULT;
3783 				}
3784 			} else {
3785 				ksym_addr = (unsigned long) prog->bpf_func;
3786 				if (put_user((u64) ksym_addr, &user_ksyms[0]))
3787 					return -EFAULT;
3788 			}
3789 		} else {
3790 			info.jited_ksyms = 0;
3791 		}
3792 	}
3793 
3794 	ulen = info.nr_jited_func_lens;
3795 	info.nr_jited_func_lens = prog->aux->func_cnt ? : 1;
3796 	if (ulen) {
3797 		if (bpf_dump_raw_ok(file->f_cred)) {
3798 			u32 __user *user_lens;
3799 			u32 func_len, i;
3800 
3801 			/* copy the JITed image lengths for each function */
3802 			ulen = min_t(u32, info.nr_jited_func_lens, ulen);
3803 			user_lens = u64_to_user_ptr(info.jited_func_lens);
3804 			if (prog->aux->func_cnt) {
3805 				for (i = 0; i < ulen; i++) {
3806 					func_len =
3807 						prog->aux->func[i]->jited_len;
3808 					if (put_user(func_len, &user_lens[i]))
3809 						return -EFAULT;
3810 				}
3811 			} else {
3812 				func_len = prog->jited_len;
3813 				if (put_user(func_len, &user_lens[0]))
3814 					return -EFAULT;
3815 			}
3816 		} else {
3817 			info.jited_func_lens = 0;
3818 		}
3819 	}
3820 
3821 	if (prog->aux->btf)
3822 		info.btf_id = btf_obj_id(prog->aux->btf);
3823 
3824 	ulen = info.nr_func_info;
3825 	info.nr_func_info = prog->aux->func_info_cnt;
3826 	if (info.nr_func_info && ulen) {
3827 		char __user *user_finfo;
3828 
3829 		user_finfo = u64_to_user_ptr(info.func_info);
3830 		ulen = min_t(u32, info.nr_func_info, ulen);
3831 		if (copy_to_user(user_finfo, prog->aux->func_info,
3832 				 info.func_info_rec_size * ulen))
3833 			return -EFAULT;
3834 	}
3835 
3836 	ulen = info.nr_line_info;
3837 	info.nr_line_info = prog->aux->nr_linfo;
3838 	if (info.nr_line_info && ulen) {
3839 		__u8 __user *user_linfo;
3840 
3841 		user_linfo = u64_to_user_ptr(info.line_info);
3842 		ulen = min_t(u32, info.nr_line_info, ulen);
3843 		if (copy_to_user(user_linfo, prog->aux->linfo,
3844 				 info.line_info_rec_size * ulen))
3845 			return -EFAULT;
3846 	}
3847 
3848 	ulen = info.nr_jited_line_info;
3849 	if (prog->aux->jited_linfo)
3850 		info.nr_jited_line_info = prog->aux->nr_linfo;
3851 	else
3852 		info.nr_jited_line_info = 0;
3853 	if (info.nr_jited_line_info && ulen) {
3854 		if (bpf_dump_raw_ok(file->f_cred)) {
3855 			__u64 __user *user_linfo;
3856 			u32 i;
3857 
3858 			user_linfo = u64_to_user_ptr(info.jited_line_info);
3859 			ulen = min_t(u32, info.nr_jited_line_info, ulen);
3860 			for (i = 0; i < ulen; i++) {
3861 				if (put_user((__u64)(long)prog->aux->jited_linfo[i],
3862 					     &user_linfo[i]))
3863 					return -EFAULT;
3864 			}
3865 		} else {
3866 			info.jited_line_info = 0;
3867 		}
3868 	}
3869 
3870 	ulen = info.nr_prog_tags;
3871 	info.nr_prog_tags = prog->aux->func_cnt ? : 1;
3872 	if (ulen) {
3873 		__u8 __user (*user_prog_tags)[BPF_TAG_SIZE];
3874 		u32 i;
3875 
3876 		user_prog_tags = u64_to_user_ptr(info.prog_tags);
3877 		ulen = min_t(u32, info.nr_prog_tags, ulen);
3878 		if (prog->aux->func_cnt) {
3879 			for (i = 0; i < ulen; i++) {
3880 				if (copy_to_user(user_prog_tags[i],
3881 						 prog->aux->func[i]->tag,
3882 						 BPF_TAG_SIZE))
3883 					return -EFAULT;
3884 			}
3885 		} else {
3886 			if (copy_to_user(user_prog_tags[0],
3887 					 prog->tag, BPF_TAG_SIZE))
3888 				return -EFAULT;
3889 		}
3890 	}
3891 
3892 done:
3893 	if (copy_to_user(uinfo, &info, info_len) ||
3894 	    put_user(info_len, &uattr->info.info_len))
3895 		return -EFAULT;
3896 
3897 	return 0;
3898 }
3899 
3900 static int bpf_map_get_info_by_fd(struct file *file,
3901 				  struct bpf_map *map,
3902 				  const union bpf_attr *attr,
3903 				  union bpf_attr __user *uattr)
3904 {
3905 	struct bpf_map_info __user *uinfo = u64_to_user_ptr(attr->info.info);
3906 	struct bpf_map_info info;
3907 	u32 info_len = attr->info.info_len;
3908 	int err;
3909 
3910 	err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len);
3911 	if (err)
3912 		return err;
3913 	info_len = min_t(u32, sizeof(info), info_len);
3914 
3915 	memset(&info, 0, sizeof(info));
3916 	info.type = map->map_type;
3917 	info.id = map->id;
3918 	info.key_size = map->key_size;
3919 	info.value_size = map->value_size;
3920 	info.max_entries = map->max_entries;
3921 	info.map_flags = map->map_flags;
3922 	info.map_extra = map->map_extra;
3923 	memcpy(info.name, map->name, sizeof(map->name));
3924 
3925 	if (map->btf) {
3926 		info.btf_id = btf_obj_id(map->btf);
3927 		info.btf_key_type_id = map->btf_key_type_id;
3928 		info.btf_value_type_id = map->btf_value_type_id;
3929 	}
3930 	info.btf_vmlinux_value_type_id = map->btf_vmlinux_value_type_id;
3931 
3932 	if (bpf_map_is_dev_bound(map)) {
3933 		err = bpf_map_offload_info_fill(&info, map);
3934 		if (err)
3935 			return err;
3936 	}
3937 
3938 	if (copy_to_user(uinfo, &info, info_len) ||
3939 	    put_user(info_len, &uattr->info.info_len))
3940 		return -EFAULT;
3941 
3942 	return 0;
3943 }
3944 
3945 static int bpf_btf_get_info_by_fd(struct file *file,
3946 				  struct btf *btf,
3947 				  const union bpf_attr *attr,
3948 				  union bpf_attr __user *uattr)
3949 {
3950 	struct bpf_btf_info __user *uinfo = u64_to_user_ptr(attr->info.info);
3951 	u32 info_len = attr->info.info_len;
3952 	int err;
3953 
3954 	err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(*uinfo), info_len);
3955 	if (err)
3956 		return err;
3957 
3958 	return btf_get_info_by_fd(btf, attr, uattr);
3959 }
3960 
3961 static int bpf_link_get_info_by_fd(struct file *file,
3962 				  struct bpf_link *link,
3963 				  const union bpf_attr *attr,
3964 				  union bpf_attr __user *uattr)
3965 {
3966 	struct bpf_link_info __user *uinfo = u64_to_user_ptr(attr->info.info);
3967 	struct bpf_link_info info;
3968 	u32 info_len = attr->info.info_len;
3969 	int err;
3970 
3971 	err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len);
3972 	if (err)
3973 		return err;
3974 	info_len = min_t(u32, sizeof(info), info_len);
3975 
3976 	memset(&info, 0, sizeof(info));
3977 	if (copy_from_user(&info, uinfo, info_len))
3978 		return -EFAULT;
3979 
3980 	info.type = link->type;
3981 	info.id = link->id;
3982 	info.prog_id = link->prog->aux->id;
3983 
3984 	if (link->ops->fill_link_info) {
3985 		err = link->ops->fill_link_info(link, &info);
3986 		if (err)
3987 			return err;
3988 	}
3989 
3990 	if (copy_to_user(uinfo, &info, info_len) ||
3991 	    put_user(info_len, &uattr->info.info_len))
3992 		return -EFAULT;
3993 
3994 	return 0;
3995 }
3996 
3997 
3998 #define BPF_OBJ_GET_INFO_BY_FD_LAST_FIELD info.info
3999 
4000 static int bpf_obj_get_info_by_fd(const union bpf_attr *attr,
4001 				  union bpf_attr __user *uattr)
4002 {
4003 	int ufd = attr->info.bpf_fd;
4004 	struct fd f;
4005 	int err;
4006 
4007 	if (CHECK_ATTR(BPF_OBJ_GET_INFO_BY_FD))
4008 		return -EINVAL;
4009 
4010 	f = fdget(ufd);
4011 	if (!f.file)
4012 		return -EBADFD;
4013 
4014 	if (f.file->f_op == &bpf_prog_fops)
4015 		err = bpf_prog_get_info_by_fd(f.file, f.file->private_data, attr,
4016 					      uattr);
4017 	else if (f.file->f_op == &bpf_map_fops)
4018 		err = bpf_map_get_info_by_fd(f.file, f.file->private_data, attr,
4019 					     uattr);
4020 	else if (f.file->f_op == &btf_fops)
4021 		err = bpf_btf_get_info_by_fd(f.file, f.file->private_data, attr, uattr);
4022 	else if (f.file->f_op == &bpf_link_fops)
4023 		err = bpf_link_get_info_by_fd(f.file, f.file->private_data,
4024 					      attr, uattr);
4025 	else
4026 		err = -EINVAL;
4027 
4028 	fdput(f);
4029 	return err;
4030 }
4031 
4032 #define BPF_BTF_LOAD_LAST_FIELD btf_log_level
4033 
4034 static int bpf_btf_load(const union bpf_attr *attr, bpfptr_t uattr)
4035 {
4036 	if (CHECK_ATTR(BPF_BTF_LOAD))
4037 		return -EINVAL;
4038 
4039 	if (!bpf_capable())
4040 		return -EPERM;
4041 
4042 	return btf_new_fd(attr, uattr);
4043 }
4044 
4045 #define BPF_BTF_GET_FD_BY_ID_LAST_FIELD btf_id
4046 
4047 static int bpf_btf_get_fd_by_id(const union bpf_attr *attr)
4048 {
4049 	if (CHECK_ATTR(BPF_BTF_GET_FD_BY_ID))
4050 		return -EINVAL;
4051 
4052 	if (!capable(CAP_SYS_ADMIN))
4053 		return -EPERM;
4054 
4055 	return btf_get_fd_by_id(attr->btf_id);
4056 }
4057 
4058 static int bpf_task_fd_query_copy(const union bpf_attr *attr,
4059 				    union bpf_attr __user *uattr,
4060 				    u32 prog_id, u32 fd_type,
4061 				    const char *buf, u64 probe_offset,
4062 				    u64 probe_addr)
4063 {
4064 	char __user *ubuf = u64_to_user_ptr(attr->task_fd_query.buf);
4065 	u32 len = buf ? strlen(buf) : 0, input_len;
4066 	int err = 0;
4067 
4068 	if (put_user(len, &uattr->task_fd_query.buf_len))
4069 		return -EFAULT;
4070 	input_len = attr->task_fd_query.buf_len;
4071 	if (input_len && ubuf) {
4072 		if (!len) {
4073 			/* nothing to copy, just make ubuf NULL terminated */
4074 			char zero = '\0';
4075 
4076 			if (put_user(zero, ubuf))
4077 				return -EFAULT;
4078 		} else if (input_len >= len + 1) {
4079 			/* ubuf can hold the string with NULL terminator */
4080 			if (copy_to_user(ubuf, buf, len + 1))
4081 				return -EFAULT;
4082 		} else {
4083 			/* ubuf cannot hold the string with NULL terminator,
4084 			 * do a partial copy with NULL terminator.
4085 			 */
4086 			char zero = '\0';
4087 
4088 			err = -ENOSPC;
4089 			if (copy_to_user(ubuf, buf, input_len - 1))
4090 				return -EFAULT;
4091 			if (put_user(zero, ubuf + input_len - 1))
4092 				return -EFAULT;
4093 		}
4094 	}
4095 
4096 	if (put_user(prog_id, &uattr->task_fd_query.prog_id) ||
4097 	    put_user(fd_type, &uattr->task_fd_query.fd_type) ||
4098 	    put_user(probe_offset, &uattr->task_fd_query.probe_offset) ||
4099 	    put_user(probe_addr, &uattr->task_fd_query.probe_addr))
4100 		return -EFAULT;
4101 
4102 	return err;
4103 }
4104 
4105 #define BPF_TASK_FD_QUERY_LAST_FIELD task_fd_query.probe_addr
4106 
4107 static int bpf_task_fd_query(const union bpf_attr *attr,
4108 			     union bpf_attr __user *uattr)
4109 {
4110 	pid_t pid = attr->task_fd_query.pid;
4111 	u32 fd = attr->task_fd_query.fd;
4112 	const struct perf_event *event;
4113 	struct task_struct *task;
4114 	struct file *file;
4115 	int err;
4116 
4117 	if (CHECK_ATTR(BPF_TASK_FD_QUERY))
4118 		return -EINVAL;
4119 
4120 	if (!capable(CAP_SYS_ADMIN))
4121 		return -EPERM;
4122 
4123 	if (attr->task_fd_query.flags != 0)
4124 		return -EINVAL;
4125 
4126 	task = get_pid_task(find_vpid(pid), PIDTYPE_PID);
4127 	if (!task)
4128 		return -ENOENT;
4129 
4130 	err = 0;
4131 	file = fget_task(task, fd);
4132 	put_task_struct(task);
4133 	if (!file)
4134 		return -EBADF;
4135 
4136 	if (file->f_op == &bpf_link_fops) {
4137 		struct bpf_link *link = file->private_data;
4138 
4139 		if (link->ops == &bpf_raw_tp_link_lops) {
4140 			struct bpf_raw_tp_link *raw_tp =
4141 				container_of(link, struct bpf_raw_tp_link, link);
4142 			struct bpf_raw_event_map *btp = raw_tp->btp;
4143 
4144 			err = bpf_task_fd_query_copy(attr, uattr,
4145 						     raw_tp->link.prog->aux->id,
4146 						     BPF_FD_TYPE_RAW_TRACEPOINT,
4147 						     btp->tp->name, 0, 0);
4148 			goto put_file;
4149 		}
4150 		goto out_not_supp;
4151 	}
4152 
4153 	event = perf_get_event(file);
4154 	if (!IS_ERR(event)) {
4155 		u64 probe_offset, probe_addr;
4156 		u32 prog_id, fd_type;
4157 		const char *buf;
4158 
4159 		err = bpf_get_perf_event_info(event, &prog_id, &fd_type,
4160 					      &buf, &probe_offset,
4161 					      &probe_addr);
4162 		if (!err)
4163 			err = bpf_task_fd_query_copy(attr, uattr, prog_id,
4164 						     fd_type, buf,
4165 						     probe_offset,
4166 						     probe_addr);
4167 		goto put_file;
4168 	}
4169 
4170 out_not_supp:
4171 	err = -ENOTSUPP;
4172 put_file:
4173 	fput(file);
4174 	return err;
4175 }
4176 
4177 #define BPF_MAP_BATCH_LAST_FIELD batch.flags
4178 
4179 #define BPF_DO_BATCH(fn)			\
4180 	do {					\
4181 		if (!fn) {			\
4182 			err = -ENOTSUPP;	\
4183 			goto err_put;		\
4184 		}				\
4185 		err = fn(map, attr, uattr);	\
4186 	} while (0)
4187 
4188 static int bpf_map_do_batch(const union bpf_attr *attr,
4189 			    union bpf_attr __user *uattr,
4190 			    int cmd)
4191 {
4192 	bool has_read  = cmd == BPF_MAP_LOOKUP_BATCH ||
4193 			 cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH;
4194 	bool has_write = cmd != BPF_MAP_LOOKUP_BATCH;
4195 	struct bpf_map *map;
4196 	int err, ufd;
4197 	struct fd f;
4198 
4199 	if (CHECK_ATTR(BPF_MAP_BATCH))
4200 		return -EINVAL;
4201 
4202 	ufd = attr->batch.map_fd;
4203 	f = fdget(ufd);
4204 	map = __bpf_map_get(f);
4205 	if (IS_ERR(map))
4206 		return PTR_ERR(map);
4207 	if (has_write)
4208 		bpf_map_write_active_inc(map);
4209 	if (has_read && !(map_get_sys_perms(map, f) & FMODE_CAN_READ)) {
4210 		err = -EPERM;
4211 		goto err_put;
4212 	}
4213 	if (has_write && !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
4214 		err = -EPERM;
4215 		goto err_put;
4216 	}
4217 
4218 	if (cmd == BPF_MAP_LOOKUP_BATCH)
4219 		BPF_DO_BATCH(map->ops->map_lookup_batch);
4220 	else if (cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH)
4221 		BPF_DO_BATCH(map->ops->map_lookup_and_delete_batch);
4222 	else if (cmd == BPF_MAP_UPDATE_BATCH)
4223 		BPF_DO_BATCH(map->ops->map_update_batch);
4224 	else
4225 		BPF_DO_BATCH(map->ops->map_delete_batch);
4226 err_put:
4227 	if (has_write)
4228 		bpf_map_write_active_dec(map);
4229 	fdput(f);
4230 	return err;
4231 }
4232 
4233 static int tracing_bpf_link_attach(const union bpf_attr *attr, bpfptr_t uattr,
4234 				   struct bpf_prog *prog)
4235 {
4236 	if (attr->link_create.attach_type != prog->expected_attach_type)
4237 		return -EINVAL;
4238 
4239 	if (prog->expected_attach_type == BPF_TRACE_ITER)
4240 		return bpf_iter_link_attach(attr, uattr, prog);
4241 	else if (prog->type == BPF_PROG_TYPE_EXT)
4242 		return bpf_tracing_prog_attach(prog,
4243 					       attr->link_create.target_fd,
4244 					       attr->link_create.target_btf_id);
4245 	return -EINVAL;
4246 }
4247 
4248 #define BPF_LINK_CREATE_LAST_FIELD link_create.iter_info_len
4249 static int link_create(union bpf_attr *attr, bpfptr_t uattr)
4250 {
4251 	enum bpf_prog_type ptype;
4252 	struct bpf_prog *prog;
4253 	int ret;
4254 
4255 	if (CHECK_ATTR(BPF_LINK_CREATE))
4256 		return -EINVAL;
4257 
4258 	prog = bpf_prog_get(attr->link_create.prog_fd);
4259 	if (IS_ERR(prog))
4260 		return PTR_ERR(prog);
4261 
4262 	ret = bpf_prog_attach_check_attach_type(prog,
4263 						attr->link_create.attach_type);
4264 	if (ret)
4265 		goto out;
4266 
4267 	switch (prog->type) {
4268 	case BPF_PROG_TYPE_EXT:
4269 		ret = tracing_bpf_link_attach(attr, uattr, prog);
4270 		goto out;
4271 	case BPF_PROG_TYPE_PERF_EVENT:
4272 	case BPF_PROG_TYPE_KPROBE:
4273 	case BPF_PROG_TYPE_TRACEPOINT:
4274 		if (attr->link_create.attach_type != BPF_PERF_EVENT) {
4275 			ret = -EINVAL;
4276 			goto out;
4277 		}
4278 		ptype = prog->type;
4279 		break;
4280 	default:
4281 		ptype = attach_type_to_prog_type(attr->link_create.attach_type);
4282 		if (ptype == BPF_PROG_TYPE_UNSPEC || ptype != prog->type) {
4283 			ret = -EINVAL;
4284 			goto out;
4285 		}
4286 		break;
4287 	}
4288 
4289 	switch (ptype) {
4290 	case BPF_PROG_TYPE_CGROUP_SKB:
4291 	case BPF_PROG_TYPE_CGROUP_SOCK:
4292 	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
4293 	case BPF_PROG_TYPE_SOCK_OPS:
4294 	case BPF_PROG_TYPE_CGROUP_DEVICE:
4295 	case BPF_PROG_TYPE_CGROUP_SYSCTL:
4296 	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
4297 		ret = cgroup_bpf_link_attach(attr, prog);
4298 		break;
4299 	case BPF_PROG_TYPE_TRACING:
4300 		ret = tracing_bpf_link_attach(attr, uattr, prog);
4301 		break;
4302 	case BPF_PROG_TYPE_FLOW_DISSECTOR:
4303 	case BPF_PROG_TYPE_SK_LOOKUP:
4304 		ret = netns_bpf_link_create(attr, prog);
4305 		break;
4306 #ifdef CONFIG_NET
4307 	case BPF_PROG_TYPE_XDP:
4308 		ret = bpf_xdp_link_attach(attr, prog);
4309 		break;
4310 #endif
4311 #ifdef CONFIG_PERF_EVENTS
4312 	case BPF_PROG_TYPE_PERF_EVENT:
4313 	case BPF_PROG_TYPE_TRACEPOINT:
4314 	case BPF_PROG_TYPE_KPROBE:
4315 		ret = bpf_perf_link_attach(attr, prog);
4316 		break;
4317 #endif
4318 	default:
4319 		ret = -EINVAL;
4320 	}
4321 
4322 out:
4323 	if (ret < 0)
4324 		bpf_prog_put(prog);
4325 	return ret;
4326 }
4327 
4328 #define BPF_LINK_UPDATE_LAST_FIELD link_update.old_prog_fd
4329 
4330 static int link_update(union bpf_attr *attr)
4331 {
4332 	struct bpf_prog *old_prog = NULL, *new_prog;
4333 	struct bpf_link *link;
4334 	u32 flags;
4335 	int ret;
4336 
4337 	if (CHECK_ATTR(BPF_LINK_UPDATE))
4338 		return -EINVAL;
4339 
4340 	flags = attr->link_update.flags;
4341 	if (flags & ~BPF_F_REPLACE)
4342 		return -EINVAL;
4343 
4344 	link = bpf_link_get_from_fd(attr->link_update.link_fd);
4345 	if (IS_ERR(link))
4346 		return PTR_ERR(link);
4347 
4348 	new_prog = bpf_prog_get(attr->link_update.new_prog_fd);
4349 	if (IS_ERR(new_prog)) {
4350 		ret = PTR_ERR(new_prog);
4351 		goto out_put_link;
4352 	}
4353 
4354 	if (flags & BPF_F_REPLACE) {
4355 		old_prog = bpf_prog_get(attr->link_update.old_prog_fd);
4356 		if (IS_ERR(old_prog)) {
4357 			ret = PTR_ERR(old_prog);
4358 			old_prog = NULL;
4359 			goto out_put_progs;
4360 		}
4361 	} else if (attr->link_update.old_prog_fd) {
4362 		ret = -EINVAL;
4363 		goto out_put_progs;
4364 	}
4365 
4366 	if (link->ops->update_prog)
4367 		ret = link->ops->update_prog(link, new_prog, old_prog);
4368 	else
4369 		ret = -EINVAL;
4370 
4371 out_put_progs:
4372 	if (old_prog)
4373 		bpf_prog_put(old_prog);
4374 	if (ret)
4375 		bpf_prog_put(new_prog);
4376 out_put_link:
4377 	bpf_link_put(link);
4378 	return ret;
4379 }
4380 
4381 #define BPF_LINK_DETACH_LAST_FIELD link_detach.link_fd
4382 
4383 static int link_detach(union bpf_attr *attr)
4384 {
4385 	struct bpf_link *link;
4386 	int ret;
4387 
4388 	if (CHECK_ATTR(BPF_LINK_DETACH))
4389 		return -EINVAL;
4390 
4391 	link = bpf_link_get_from_fd(attr->link_detach.link_fd);
4392 	if (IS_ERR(link))
4393 		return PTR_ERR(link);
4394 
4395 	if (link->ops->detach)
4396 		ret = link->ops->detach(link);
4397 	else
4398 		ret = -EOPNOTSUPP;
4399 
4400 	bpf_link_put(link);
4401 	return ret;
4402 }
4403 
4404 static struct bpf_link *bpf_link_inc_not_zero(struct bpf_link *link)
4405 {
4406 	return atomic64_fetch_add_unless(&link->refcnt, 1, 0) ? link : ERR_PTR(-ENOENT);
4407 }
4408 
4409 struct bpf_link *bpf_link_by_id(u32 id)
4410 {
4411 	struct bpf_link *link;
4412 
4413 	if (!id)
4414 		return ERR_PTR(-ENOENT);
4415 
4416 	spin_lock_bh(&link_idr_lock);
4417 	/* before link is "settled", ID is 0, pretend it doesn't exist yet */
4418 	link = idr_find(&link_idr, id);
4419 	if (link) {
4420 		if (link->id)
4421 			link = bpf_link_inc_not_zero(link);
4422 		else
4423 			link = ERR_PTR(-EAGAIN);
4424 	} else {
4425 		link = ERR_PTR(-ENOENT);
4426 	}
4427 	spin_unlock_bh(&link_idr_lock);
4428 	return link;
4429 }
4430 
4431 #define BPF_LINK_GET_FD_BY_ID_LAST_FIELD link_id
4432 
4433 static int bpf_link_get_fd_by_id(const union bpf_attr *attr)
4434 {
4435 	struct bpf_link *link;
4436 	u32 id = attr->link_id;
4437 	int fd;
4438 
4439 	if (CHECK_ATTR(BPF_LINK_GET_FD_BY_ID))
4440 		return -EINVAL;
4441 
4442 	if (!capable(CAP_SYS_ADMIN))
4443 		return -EPERM;
4444 
4445 	link = bpf_link_by_id(id);
4446 	if (IS_ERR(link))
4447 		return PTR_ERR(link);
4448 
4449 	fd = bpf_link_new_fd(link);
4450 	if (fd < 0)
4451 		bpf_link_put(link);
4452 
4453 	return fd;
4454 }
4455 
4456 DEFINE_MUTEX(bpf_stats_enabled_mutex);
4457 
4458 static int bpf_stats_release(struct inode *inode, struct file *file)
4459 {
4460 	mutex_lock(&bpf_stats_enabled_mutex);
4461 	static_key_slow_dec(&bpf_stats_enabled_key.key);
4462 	mutex_unlock(&bpf_stats_enabled_mutex);
4463 	return 0;
4464 }
4465 
4466 static const struct file_operations bpf_stats_fops = {
4467 	.release = bpf_stats_release,
4468 };
4469 
4470 static int bpf_enable_runtime_stats(void)
4471 {
4472 	int fd;
4473 
4474 	mutex_lock(&bpf_stats_enabled_mutex);
4475 
4476 	/* Set a very high limit to avoid overflow */
4477 	if (static_key_count(&bpf_stats_enabled_key.key) > INT_MAX / 2) {
4478 		mutex_unlock(&bpf_stats_enabled_mutex);
4479 		return -EBUSY;
4480 	}
4481 
4482 	fd = anon_inode_getfd("bpf-stats", &bpf_stats_fops, NULL, O_CLOEXEC);
4483 	if (fd >= 0)
4484 		static_key_slow_inc(&bpf_stats_enabled_key.key);
4485 
4486 	mutex_unlock(&bpf_stats_enabled_mutex);
4487 	return fd;
4488 }
4489 
4490 #define BPF_ENABLE_STATS_LAST_FIELD enable_stats.type
4491 
4492 static int bpf_enable_stats(union bpf_attr *attr)
4493 {
4494 
4495 	if (CHECK_ATTR(BPF_ENABLE_STATS))
4496 		return -EINVAL;
4497 
4498 	if (!capable(CAP_SYS_ADMIN))
4499 		return -EPERM;
4500 
4501 	switch (attr->enable_stats.type) {
4502 	case BPF_STATS_RUN_TIME:
4503 		return bpf_enable_runtime_stats();
4504 	default:
4505 		break;
4506 	}
4507 	return -EINVAL;
4508 }
4509 
4510 #define BPF_ITER_CREATE_LAST_FIELD iter_create.flags
4511 
4512 static int bpf_iter_create(union bpf_attr *attr)
4513 {
4514 	struct bpf_link *link;
4515 	int err;
4516 
4517 	if (CHECK_ATTR(BPF_ITER_CREATE))
4518 		return -EINVAL;
4519 
4520 	if (attr->iter_create.flags)
4521 		return -EINVAL;
4522 
4523 	link = bpf_link_get_from_fd(attr->iter_create.link_fd);
4524 	if (IS_ERR(link))
4525 		return PTR_ERR(link);
4526 
4527 	err = bpf_iter_new_fd(link);
4528 	bpf_link_put(link);
4529 
4530 	return err;
4531 }
4532 
4533 #define BPF_PROG_BIND_MAP_LAST_FIELD prog_bind_map.flags
4534 
4535 static int bpf_prog_bind_map(union bpf_attr *attr)
4536 {
4537 	struct bpf_prog *prog;
4538 	struct bpf_map *map;
4539 	struct bpf_map **used_maps_old, **used_maps_new;
4540 	int i, ret = 0;
4541 
4542 	if (CHECK_ATTR(BPF_PROG_BIND_MAP))
4543 		return -EINVAL;
4544 
4545 	if (attr->prog_bind_map.flags)
4546 		return -EINVAL;
4547 
4548 	prog = bpf_prog_get(attr->prog_bind_map.prog_fd);
4549 	if (IS_ERR(prog))
4550 		return PTR_ERR(prog);
4551 
4552 	map = bpf_map_get(attr->prog_bind_map.map_fd);
4553 	if (IS_ERR(map)) {
4554 		ret = PTR_ERR(map);
4555 		goto out_prog_put;
4556 	}
4557 
4558 	mutex_lock(&prog->aux->used_maps_mutex);
4559 
4560 	used_maps_old = prog->aux->used_maps;
4561 
4562 	for (i = 0; i < prog->aux->used_map_cnt; i++)
4563 		if (used_maps_old[i] == map) {
4564 			bpf_map_put(map);
4565 			goto out_unlock;
4566 		}
4567 
4568 	used_maps_new = kmalloc_array(prog->aux->used_map_cnt + 1,
4569 				      sizeof(used_maps_new[0]),
4570 				      GFP_KERNEL);
4571 	if (!used_maps_new) {
4572 		ret = -ENOMEM;
4573 		goto out_unlock;
4574 	}
4575 
4576 	memcpy(used_maps_new, used_maps_old,
4577 	       sizeof(used_maps_old[0]) * prog->aux->used_map_cnt);
4578 	used_maps_new[prog->aux->used_map_cnt] = map;
4579 
4580 	prog->aux->used_map_cnt++;
4581 	prog->aux->used_maps = used_maps_new;
4582 
4583 	kfree(used_maps_old);
4584 
4585 out_unlock:
4586 	mutex_unlock(&prog->aux->used_maps_mutex);
4587 
4588 	if (ret)
4589 		bpf_map_put(map);
4590 out_prog_put:
4591 	bpf_prog_put(prog);
4592 	return ret;
4593 }
4594 
4595 static int __sys_bpf(int cmd, bpfptr_t uattr, unsigned int size)
4596 {
4597 	union bpf_attr attr;
4598 	int err;
4599 
4600 	if (sysctl_unprivileged_bpf_disabled && !bpf_capable())
4601 		return -EPERM;
4602 
4603 	err = bpf_check_uarg_tail_zero(uattr, sizeof(attr), size);
4604 	if (err)
4605 		return err;
4606 	size = min_t(u32, size, sizeof(attr));
4607 
4608 	/* copy attributes from user space, may be less than sizeof(bpf_attr) */
4609 	memset(&attr, 0, sizeof(attr));
4610 	if (copy_from_bpfptr(&attr, uattr, size) != 0)
4611 		return -EFAULT;
4612 
4613 	err = security_bpf(cmd, &attr, size);
4614 	if (err < 0)
4615 		return err;
4616 
4617 	switch (cmd) {
4618 	case BPF_MAP_CREATE:
4619 		err = map_create(&attr);
4620 		break;
4621 	case BPF_MAP_LOOKUP_ELEM:
4622 		err = map_lookup_elem(&attr);
4623 		break;
4624 	case BPF_MAP_UPDATE_ELEM:
4625 		err = map_update_elem(&attr, uattr);
4626 		break;
4627 	case BPF_MAP_DELETE_ELEM:
4628 		err = map_delete_elem(&attr);
4629 		break;
4630 	case BPF_MAP_GET_NEXT_KEY:
4631 		err = map_get_next_key(&attr);
4632 		break;
4633 	case BPF_MAP_FREEZE:
4634 		err = map_freeze(&attr);
4635 		break;
4636 	case BPF_PROG_LOAD:
4637 		err = bpf_prog_load(&attr, uattr);
4638 		break;
4639 	case BPF_OBJ_PIN:
4640 		err = bpf_obj_pin(&attr);
4641 		break;
4642 	case BPF_OBJ_GET:
4643 		err = bpf_obj_get(&attr);
4644 		break;
4645 	case BPF_PROG_ATTACH:
4646 		err = bpf_prog_attach(&attr);
4647 		break;
4648 	case BPF_PROG_DETACH:
4649 		err = bpf_prog_detach(&attr);
4650 		break;
4651 	case BPF_PROG_QUERY:
4652 		err = bpf_prog_query(&attr, uattr.user);
4653 		break;
4654 	case BPF_PROG_TEST_RUN:
4655 		err = bpf_prog_test_run(&attr, uattr.user);
4656 		break;
4657 	case BPF_PROG_GET_NEXT_ID:
4658 		err = bpf_obj_get_next_id(&attr, uattr.user,
4659 					  &prog_idr, &prog_idr_lock);
4660 		break;
4661 	case BPF_MAP_GET_NEXT_ID:
4662 		err = bpf_obj_get_next_id(&attr, uattr.user,
4663 					  &map_idr, &map_idr_lock);
4664 		break;
4665 	case BPF_BTF_GET_NEXT_ID:
4666 		err = bpf_obj_get_next_id(&attr, uattr.user,
4667 					  &btf_idr, &btf_idr_lock);
4668 		break;
4669 	case BPF_PROG_GET_FD_BY_ID:
4670 		err = bpf_prog_get_fd_by_id(&attr);
4671 		break;
4672 	case BPF_MAP_GET_FD_BY_ID:
4673 		err = bpf_map_get_fd_by_id(&attr);
4674 		break;
4675 	case BPF_OBJ_GET_INFO_BY_FD:
4676 		err = bpf_obj_get_info_by_fd(&attr, uattr.user);
4677 		break;
4678 	case BPF_RAW_TRACEPOINT_OPEN:
4679 		err = bpf_raw_tracepoint_open(&attr);
4680 		break;
4681 	case BPF_BTF_LOAD:
4682 		err = bpf_btf_load(&attr, uattr);
4683 		break;
4684 	case BPF_BTF_GET_FD_BY_ID:
4685 		err = bpf_btf_get_fd_by_id(&attr);
4686 		break;
4687 	case BPF_TASK_FD_QUERY:
4688 		err = bpf_task_fd_query(&attr, uattr.user);
4689 		break;
4690 	case BPF_MAP_LOOKUP_AND_DELETE_ELEM:
4691 		err = map_lookup_and_delete_elem(&attr);
4692 		break;
4693 	case BPF_MAP_LOOKUP_BATCH:
4694 		err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_LOOKUP_BATCH);
4695 		break;
4696 	case BPF_MAP_LOOKUP_AND_DELETE_BATCH:
4697 		err = bpf_map_do_batch(&attr, uattr.user,
4698 				       BPF_MAP_LOOKUP_AND_DELETE_BATCH);
4699 		break;
4700 	case BPF_MAP_UPDATE_BATCH:
4701 		err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_UPDATE_BATCH);
4702 		break;
4703 	case BPF_MAP_DELETE_BATCH:
4704 		err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_DELETE_BATCH);
4705 		break;
4706 	case BPF_LINK_CREATE:
4707 		err = link_create(&attr, uattr);
4708 		break;
4709 	case BPF_LINK_UPDATE:
4710 		err = link_update(&attr);
4711 		break;
4712 	case BPF_LINK_GET_FD_BY_ID:
4713 		err = bpf_link_get_fd_by_id(&attr);
4714 		break;
4715 	case BPF_LINK_GET_NEXT_ID:
4716 		err = bpf_obj_get_next_id(&attr, uattr.user,
4717 					  &link_idr, &link_idr_lock);
4718 		break;
4719 	case BPF_ENABLE_STATS:
4720 		err = bpf_enable_stats(&attr);
4721 		break;
4722 	case BPF_ITER_CREATE:
4723 		err = bpf_iter_create(&attr);
4724 		break;
4725 	case BPF_LINK_DETACH:
4726 		err = link_detach(&attr);
4727 		break;
4728 	case BPF_PROG_BIND_MAP:
4729 		err = bpf_prog_bind_map(&attr);
4730 		break;
4731 	default:
4732 		err = -EINVAL;
4733 		break;
4734 	}
4735 
4736 	return err;
4737 }
4738 
4739 SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size)
4740 {
4741 	return __sys_bpf(cmd, USER_BPFPTR(uattr), size);
4742 }
4743 
4744 static bool syscall_prog_is_valid_access(int off, int size,
4745 					 enum bpf_access_type type,
4746 					 const struct bpf_prog *prog,
4747 					 struct bpf_insn_access_aux *info)
4748 {
4749 	if (off < 0 || off >= U16_MAX)
4750 		return false;
4751 	if (off % size != 0)
4752 		return false;
4753 	return true;
4754 }
4755 
4756 BPF_CALL_3(bpf_sys_bpf, int, cmd, void *, attr, u32, attr_size)
4757 {
4758 	switch (cmd) {
4759 	case BPF_MAP_CREATE:
4760 	case BPF_MAP_UPDATE_ELEM:
4761 	case BPF_MAP_FREEZE:
4762 	case BPF_PROG_LOAD:
4763 	case BPF_BTF_LOAD:
4764 		break;
4765 	/* case BPF_PROG_TEST_RUN:
4766 	 * is not part of this list to prevent recursive test_run
4767 	 */
4768 	default:
4769 		return -EINVAL;
4770 	}
4771 	return __sys_bpf(cmd, KERNEL_BPFPTR(attr), attr_size);
4772 }
4773 
4774 static const struct bpf_func_proto bpf_sys_bpf_proto = {
4775 	.func		= bpf_sys_bpf,
4776 	.gpl_only	= false,
4777 	.ret_type	= RET_INTEGER,
4778 	.arg1_type	= ARG_ANYTHING,
4779 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
4780 	.arg3_type	= ARG_CONST_SIZE,
4781 };
4782 
4783 const struct bpf_func_proto * __weak
4784 tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
4785 {
4786 	return bpf_base_func_proto(func_id);
4787 }
4788 
4789 BPF_CALL_1(bpf_sys_close, u32, fd)
4790 {
4791 	/* When bpf program calls this helper there should not be
4792 	 * an fdget() without matching completed fdput().
4793 	 * This helper is allowed in the following callchain only:
4794 	 * sys_bpf->prog_test_run->bpf_prog->bpf_sys_close
4795 	 */
4796 	return close_fd(fd);
4797 }
4798 
4799 static const struct bpf_func_proto bpf_sys_close_proto = {
4800 	.func		= bpf_sys_close,
4801 	.gpl_only	= false,
4802 	.ret_type	= RET_INTEGER,
4803 	.arg1_type	= ARG_ANYTHING,
4804 };
4805 
4806 BPF_CALL_4(bpf_kallsyms_lookup_name, const char *, name, int, name_sz, int, flags, u64 *, res)
4807 {
4808 	if (flags)
4809 		return -EINVAL;
4810 
4811 	if (name_sz <= 1 || name[name_sz - 1])
4812 		return -EINVAL;
4813 
4814 	if (!bpf_dump_raw_ok(current_cred()))
4815 		return -EPERM;
4816 
4817 	*res = kallsyms_lookup_name(name);
4818 	return *res ? 0 : -ENOENT;
4819 }
4820 
4821 const struct bpf_func_proto bpf_kallsyms_lookup_name_proto = {
4822 	.func		= bpf_kallsyms_lookup_name,
4823 	.gpl_only	= false,
4824 	.ret_type	= RET_INTEGER,
4825 	.arg1_type	= ARG_PTR_TO_MEM,
4826 	.arg2_type	= ARG_CONST_SIZE_OR_ZERO,
4827 	.arg3_type	= ARG_ANYTHING,
4828 	.arg4_type	= ARG_PTR_TO_LONG,
4829 };
4830 
4831 static const struct bpf_func_proto *
4832 syscall_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
4833 {
4834 	switch (func_id) {
4835 	case BPF_FUNC_sys_bpf:
4836 		return &bpf_sys_bpf_proto;
4837 	case BPF_FUNC_btf_find_by_name_kind:
4838 		return &bpf_btf_find_by_name_kind_proto;
4839 	case BPF_FUNC_sys_close:
4840 		return &bpf_sys_close_proto;
4841 	case BPF_FUNC_kallsyms_lookup_name:
4842 		return &bpf_kallsyms_lookup_name_proto;
4843 	default:
4844 		return tracing_prog_func_proto(func_id, prog);
4845 	}
4846 }
4847 
4848 const struct bpf_verifier_ops bpf_syscall_verifier_ops = {
4849 	.get_func_proto  = syscall_prog_func_proto,
4850 	.is_valid_access = syscall_prog_is_valid_access,
4851 };
4852 
4853 const struct bpf_prog_ops bpf_syscall_prog_ops = {
4854 	.test_run = bpf_prog_test_run_syscall,
4855 };
4856