xref: /openbmc/linux/kernel/bpf/syscall.c (revision 34fa67e7)
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 	}
1359 	if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp)))
1360 		err = -EFAULT;
1361 
1362 	kvfree(key);
1363 	return err;
1364 }
1365 
1366 int generic_map_update_batch(struct bpf_map *map,
1367 			     const union bpf_attr *attr,
1368 			     union bpf_attr __user *uattr)
1369 {
1370 	void __user *values = u64_to_user_ptr(attr->batch.values);
1371 	void __user *keys = u64_to_user_ptr(attr->batch.keys);
1372 	u32 value_size, cp, max_count;
1373 	int ufd = attr->batch.map_fd;
1374 	void *key, *value;
1375 	struct fd f;
1376 	int err = 0;
1377 
1378 	if (attr->batch.elem_flags & ~BPF_F_LOCK)
1379 		return -EINVAL;
1380 
1381 	if ((attr->batch.elem_flags & BPF_F_LOCK) &&
1382 	    !map_value_has_spin_lock(map)) {
1383 		return -EINVAL;
1384 	}
1385 
1386 	value_size = bpf_map_value_size(map);
1387 
1388 	max_count = attr->batch.count;
1389 	if (!max_count)
1390 		return 0;
1391 
1392 	key = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN);
1393 	if (!key)
1394 		return -ENOMEM;
1395 
1396 	value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN);
1397 	if (!value) {
1398 		kvfree(key);
1399 		return -ENOMEM;
1400 	}
1401 
1402 	f = fdget(ufd); /* bpf_map_do_batch() guarantees ufd is valid */
1403 	for (cp = 0; cp < max_count; cp++) {
1404 		err = -EFAULT;
1405 		if (copy_from_user(key, keys + cp * map->key_size,
1406 		    map->key_size) ||
1407 		    copy_from_user(value, values + cp * value_size, value_size))
1408 			break;
1409 
1410 		err = bpf_map_update_value(map, f, key, value,
1411 					   attr->batch.elem_flags);
1412 
1413 		if (err)
1414 			break;
1415 	}
1416 
1417 	if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp)))
1418 		err = -EFAULT;
1419 
1420 	kvfree(value);
1421 	kvfree(key);
1422 	fdput(f);
1423 	return err;
1424 }
1425 
1426 #define MAP_LOOKUP_RETRIES 3
1427 
1428 int generic_map_lookup_batch(struct bpf_map *map,
1429 				    const union bpf_attr *attr,
1430 				    union bpf_attr __user *uattr)
1431 {
1432 	void __user *uobatch = u64_to_user_ptr(attr->batch.out_batch);
1433 	void __user *ubatch = u64_to_user_ptr(attr->batch.in_batch);
1434 	void __user *values = u64_to_user_ptr(attr->batch.values);
1435 	void __user *keys = u64_to_user_ptr(attr->batch.keys);
1436 	void *buf, *buf_prevkey, *prev_key, *key, *value;
1437 	int err, retry = MAP_LOOKUP_RETRIES;
1438 	u32 value_size, cp, max_count;
1439 
1440 	if (attr->batch.elem_flags & ~BPF_F_LOCK)
1441 		return -EINVAL;
1442 
1443 	if ((attr->batch.elem_flags & BPF_F_LOCK) &&
1444 	    !map_value_has_spin_lock(map))
1445 		return -EINVAL;
1446 
1447 	value_size = bpf_map_value_size(map);
1448 
1449 	max_count = attr->batch.count;
1450 	if (!max_count)
1451 		return 0;
1452 
1453 	if (put_user(0, &uattr->batch.count))
1454 		return -EFAULT;
1455 
1456 	buf_prevkey = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN);
1457 	if (!buf_prevkey)
1458 		return -ENOMEM;
1459 
1460 	buf = kvmalloc(map->key_size + value_size, GFP_USER | __GFP_NOWARN);
1461 	if (!buf) {
1462 		kvfree(buf_prevkey);
1463 		return -ENOMEM;
1464 	}
1465 
1466 	err = -EFAULT;
1467 	prev_key = NULL;
1468 	if (ubatch && copy_from_user(buf_prevkey, ubatch, map->key_size))
1469 		goto free_buf;
1470 	key = buf;
1471 	value = key + map->key_size;
1472 	if (ubatch)
1473 		prev_key = buf_prevkey;
1474 
1475 	for (cp = 0; cp < max_count;) {
1476 		rcu_read_lock();
1477 		err = map->ops->map_get_next_key(map, prev_key, key);
1478 		rcu_read_unlock();
1479 		if (err)
1480 			break;
1481 		err = bpf_map_copy_value(map, key, value,
1482 					 attr->batch.elem_flags);
1483 
1484 		if (err == -ENOENT) {
1485 			if (retry) {
1486 				retry--;
1487 				continue;
1488 			}
1489 			err = -EINTR;
1490 			break;
1491 		}
1492 
1493 		if (err)
1494 			goto free_buf;
1495 
1496 		if (copy_to_user(keys + cp * map->key_size, key,
1497 				 map->key_size)) {
1498 			err = -EFAULT;
1499 			goto free_buf;
1500 		}
1501 		if (copy_to_user(values + cp * value_size, value, value_size)) {
1502 			err = -EFAULT;
1503 			goto free_buf;
1504 		}
1505 
1506 		if (!prev_key)
1507 			prev_key = buf_prevkey;
1508 
1509 		swap(prev_key, key);
1510 		retry = MAP_LOOKUP_RETRIES;
1511 		cp++;
1512 	}
1513 
1514 	if (err == -EFAULT)
1515 		goto free_buf;
1516 
1517 	if ((copy_to_user(&uattr->batch.count, &cp, sizeof(cp)) ||
1518 		    (cp && copy_to_user(uobatch, prev_key, map->key_size))))
1519 		err = -EFAULT;
1520 
1521 free_buf:
1522 	kvfree(buf_prevkey);
1523 	kvfree(buf);
1524 	return err;
1525 }
1526 
1527 #define BPF_MAP_LOOKUP_AND_DELETE_ELEM_LAST_FIELD flags
1528 
1529 static int map_lookup_and_delete_elem(union bpf_attr *attr)
1530 {
1531 	void __user *ukey = u64_to_user_ptr(attr->key);
1532 	void __user *uvalue = u64_to_user_ptr(attr->value);
1533 	int ufd = attr->map_fd;
1534 	struct bpf_map *map;
1535 	void *key, *value;
1536 	u32 value_size;
1537 	struct fd f;
1538 	int err;
1539 
1540 	if (CHECK_ATTR(BPF_MAP_LOOKUP_AND_DELETE_ELEM))
1541 		return -EINVAL;
1542 
1543 	if (attr->flags & ~BPF_F_LOCK)
1544 		return -EINVAL;
1545 
1546 	f = fdget(ufd);
1547 	map = __bpf_map_get(f);
1548 	if (IS_ERR(map))
1549 		return PTR_ERR(map);
1550 	bpf_map_write_active_inc(map);
1551 	if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ) ||
1552 	    !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
1553 		err = -EPERM;
1554 		goto err_put;
1555 	}
1556 
1557 	if (attr->flags &&
1558 	    (map->map_type == BPF_MAP_TYPE_QUEUE ||
1559 	     map->map_type == BPF_MAP_TYPE_STACK)) {
1560 		err = -EINVAL;
1561 		goto err_put;
1562 	}
1563 
1564 	if ((attr->flags & BPF_F_LOCK) &&
1565 	    !map_value_has_spin_lock(map)) {
1566 		err = -EINVAL;
1567 		goto err_put;
1568 	}
1569 
1570 	key = __bpf_copy_key(ukey, map->key_size);
1571 	if (IS_ERR(key)) {
1572 		err = PTR_ERR(key);
1573 		goto err_put;
1574 	}
1575 
1576 	value_size = bpf_map_value_size(map);
1577 
1578 	err = -ENOMEM;
1579 	value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN);
1580 	if (!value)
1581 		goto free_key;
1582 
1583 	err = -ENOTSUPP;
1584 	if (map->map_type == BPF_MAP_TYPE_QUEUE ||
1585 	    map->map_type == BPF_MAP_TYPE_STACK) {
1586 		err = map->ops->map_pop_elem(map, value);
1587 	} else if (map->map_type == BPF_MAP_TYPE_HASH ||
1588 		   map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
1589 		   map->map_type == BPF_MAP_TYPE_LRU_HASH ||
1590 		   map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
1591 		if (!bpf_map_is_dev_bound(map)) {
1592 			bpf_disable_instrumentation();
1593 			rcu_read_lock();
1594 			err = map->ops->map_lookup_and_delete_elem(map, key, value, attr->flags);
1595 			rcu_read_unlock();
1596 			bpf_enable_instrumentation();
1597 		}
1598 	}
1599 
1600 	if (err)
1601 		goto free_value;
1602 
1603 	if (copy_to_user(uvalue, value, value_size) != 0) {
1604 		err = -EFAULT;
1605 		goto free_value;
1606 	}
1607 
1608 	err = 0;
1609 
1610 free_value:
1611 	kvfree(value);
1612 free_key:
1613 	kvfree(key);
1614 err_put:
1615 	bpf_map_write_active_dec(map);
1616 	fdput(f);
1617 	return err;
1618 }
1619 
1620 #define BPF_MAP_FREEZE_LAST_FIELD map_fd
1621 
1622 static int map_freeze(const union bpf_attr *attr)
1623 {
1624 	int err = 0, ufd = attr->map_fd;
1625 	struct bpf_map *map;
1626 	struct fd f;
1627 
1628 	if (CHECK_ATTR(BPF_MAP_FREEZE))
1629 		return -EINVAL;
1630 
1631 	f = fdget(ufd);
1632 	map = __bpf_map_get(f);
1633 	if (IS_ERR(map))
1634 		return PTR_ERR(map);
1635 
1636 	if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS ||
1637 	    map_value_has_timer(map)) {
1638 		fdput(f);
1639 		return -ENOTSUPP;
1640 	}
1641 
1642 	mutex_lock(&map->freeze_mutex);
1643 	if (bpf_map_write_active(map)) {
1644 		err = -EBUSY;
1645 		goto err_put;
1646 	}
1647 	if (READ_ONCE(map->frozen)) {
1648 		err = -EBUSY;
1649 		goto err_put;
1650 	}
1651 	if (!bpf_capable()) {
1652 		err = -EPERM;
1653 		goto err_put;
1654 	}
1655 
1656 	WRITE_ONCE(map->frozen, true);
1657 err_put:
1658 	mutex_unlock(&map->freeze_mutex);
1659 	fdput(f);
1660 	return err;
1661 }
1662 
1663 static const struct bpf_prog_ops * const bpf_prog_types[] = {
1664 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) \
1665 	[_id] = & _name ## _prog_ops,
1666 #define BPF_MAP_TYPE(_id, _ops)
1667 #define BPF_LINK_TYPE(_id, _name)
1668 #include <linux/bpf_types.h>
1669 #undef BPF_PROG_TYPE
1670 #undef BPF_MAP_TYPE
1671 #undef BPF_LINK_TYPE
1672 };
1673 
1674 static int find_prog_type(enum bpf_prog_type type, struct bpf_prog *prog)
1675 {
1676 	const struct bpf_prog_ops *ops;
1677 
1678 	if (type >= ARRAY_SIZE(bpf_prog_types))
1679 		return -EINVAL;
1680 	type = array_index_nospec(type, ARRAY_SIZE(bpf_prog_types));
1681 	ops = bpf_prog_types[type];
1682 	if (!ops)
1683 		return -EINVAL;
1684 
1685 	if (!bpf_prog_is_dev_bound(prog->aux))
1686 		prog->aux->ops = ops;
1687 	else
1688 		prog->aux->ops = &bpf_offload_prog_ops;
1689 	prog->type = type;
1690 	return 0;
1691 }
1692 
1693 enum bpf_audit {
1694 	BPF_AUDIT_LOAD,
1695 	BPF_AUDIT_UNLOAD,
1696 	BPF_AUDIT_MAX,
1697 };
1698 
1699 static const char * const bpf_audit_str[BPF_AUDIT_MAX] = {
1700 	[BPF_AUDIT_LOAD]   = "LOAD",
1701 	[BPF_AUDIT_UNLOAD] = "UNLOAD",
1702 };
1703 
1704 static void bpf_audit_prog(const struct bpf_prog *prog, unsigned int op)
1705 {
1706 	struct audit_context *ctx = NULL;
1707 	struct audit_buffer *ab;
1708 
1709 	if (WARN_ON_ONCE(op >= BPF_AUDIT_MAX))
1710 		return;
1711 	if (audit_enabled == AUDIT_OFF)
1712 		return;
1713 	if (op == BPF_AUDIT_LOAD)
1714 		ctx = audit_context();
1715 	ab = audit_log_start(ctx, GFP_ATOMIC, AUDIT_BPF);
1716 	if (unlikely(!ab))
1717 		return;
1718 	audit_log_format(ab, "prog-id=%u op=%s",
1719 			 prog->aux->id, bpf_audit_str[op]);
1720 	audit_log_end(ab);
1721 }
1722 
1723 static int bpf_prog_alloc_id(struct bpf_prog *prog)
1724 {
1725 	int id;
1726 
1727 	idr_preload(GFP_KERNEL);
1728 	spin_lock_bh(&prog_idr_lock);
1729 	id = idr_alloc_cyclic(&prog_idr, prog, 1, INT_MAX, GFP_ATOMIC);
1730 	if (id > 0)
1731 		prog->aux->id = id;
1732 	spin_unlock_bh(&prog_idr_lock);
1733 	idr_preload_end();
1734 
1735 	/* id is in [1, INT_MAX) */
1736 	if (WARN_ON_ONCE(!id))
1737 		return -ENOSPC;
1738 
1739 	return id > 0 ? 0 : id;
1740 }
1741 
1742 void bpf_prog_free_id(struct bpf_prog *prog, bool do_idr_lock)
1743 {
1744 	unsigned long flags;
1745 
1746 	/* cBPF to eBPF migrations are currently not in the idr store.
1747 	 * Offloaded programs are removed from the store when their device
1748 	 * disappears - even if someone grabs an fd to them they are unusable,
1749 	 * simply waiting for refcnt to drop to be freed.
1750 	 */
1751 	if (!prog->aux->id)
1752 		return;
1753 
1754 	if (do_idr_lock)
1755 		spin_lock_irqsave(&prog_idr_lock, flags);
1756 	else
1757 		__acquire(&prog_idr_lock);
1758 
1759 	idr_remove(&prog_idr, prog->aux->id);
1760 	prog->aux->id = 0;
1761 
1762 	if (do_idr_lock)
1763 		spin_unlock_irqrestore(&prog_idr_lock, flags);
1764 	else
1765 		__release(&prog_idr_lock);
1766 }
1767 
1768 static void __bpf_prog_put_rcu(struct rcu_head *rcu)
1769 {
1770 	struct bpf_prog_aux *aux = container_of(rcu, struct bpf_prog_aux, rcu);
1771 
1772 	kvfree(aux->func_info);
1773 	kfree(aux->func_info_aux);
1774 	free_uid(aux->user);
1775 	security_bpf_prog_free(aux);
1776 	bpf_prog_free(aux->prog);
1777 }
1778 
1779 static void __bpf_prog_put_noref(struct bpf_prog *prog, bool deferred)
1780 {
1781 	bpf_prog_kallsyms_del_all(prog);
1782 	btf_put(prog->aux->btf);
1783 	kvfree(prog->aux->jited_linfo);
1784 	kvfree(prog->aux->linfo);
1785 	kfree(prog->aux->kfunc_tab);
1786 	if (prog->aux->attach_btf)
1787 		btf_put(prog->aux->attach_btf);
1788 
1789 	if (deferred) {
1790 		if (prog->aux->sleepable)
1791 			call_rcu_tasks_trace(&prog->aux->rcu, __bpf_prog_put_rcu);
1792 		else
1793 			call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu);
1794 	} else {
1795 		__bpf_prog_put_rcu(&prog->aux->rcu);
1796 	}
1797 }
1798 
1799 static void bpf_prog_put_deferred(struct work_struct *work)
1800 {
1801 	struct bpf_prog_aux *aux;
1802 	struct bpf_prog *prog;
1803 
1804 	aux = container_of(work, struct bpf_prog_aux, work);
1805 	prog = aux->prog;
1806 	perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_UNLOAD, 0);
1807 	bpf_audit_prog(prog, BPF_AUDIT_UNLOAD);
1808 	__bpf_prog_put_noref(prog, true);
1809 }
1810 
1811 static void __bpf_prog_put(struct bpf_prog *prog, bool do_idr_lock)
1812 {
1813 	struct bpf_prog_aux *aux = prog->aux;
1814 
1815 	if (atomic64_dec_and_test(&aux->refcnt)) {
1816 		/* bpf_prog_free_id() must be called first */
1817 		bpf_prog_free_id(prog, do_idr_lock);
1818 
1819 		if (in_irq() || irqs_disabled()) {
1820 			INIT_WORK(&aux->work, bpf_prog_put_deferred);
1821 			schedule_work(&aux->work);
1822 		} else {
1823 			bpf_prog_put_deferred(&aux->work);
1824 		}
1825 	}
1826 }
1827 
1828 void bpf_prog_put(struct bpf_prog *prog)
1829 {
1830 	__bpf_prog_put(prog, true);
1831 }
1832 EXPORT_SYMBOL_GPL(bpf_prog_put);
1833 
1834 static int bpf_prog_release(struct inode *inode, struct file *filp)
1835 {
1836 	struct bpf_prog *prog = filp->private_data;
1837 
1838 	bpf_prog_put(prog);
1839 	return 0;
1840 }
1841 
1842 struct bpf_prog_kstats {
1843 	u64 nsecs;
1844 	u64 cnt;
1845 	u64 misses;
1846 };
1847 
1848 static void bpf_prog_get_stats(const struct bpf_prog *prog,
1849 			       struct bpf_prog_kstats *stats)
1850 {
1851 	u64 nsecs = 0, cnt = 0, misses = 0;
1852 	int cpu;
1853 
1854 	for_each_possible_cpu(cpu) {
1855 		const struct bpf_prog_stats *st;
1856 		unsigned int start;
1857 		u64 tnsecs, tcnt, tmisses;
1858 
1859 		st = per_cpu_ptr(prog->stats, cpu);
1860 		do {
1861 			start = u64_stats_fetch_begin_irq(&st->syncp);
1862 			tnsecs = u64_stats_read(&st->nsecs);
1863 			tcnt = u64_stats_read(&st->cnt);
1864 			tmisses = u64_stats_read(&st->misses);
1865 		} while (u64_stats_fetch_retry_irq(&st->syncp, start));
1866 		nsecs += tnsecs;
1867 		cnt += tcnt;
1868 		misses += tmisses;
1869 	}
1870 	stats->nsecs = nsecs;
1871 	stats->cnt = cnt;
1872 	stats->misses = misses;
1873 }
1874 
1875 #ifdef CONFIG_PROC_FS
1876 static void bpf_prog_show_fdinfo(struct seq_file *m, struct file *filp)
1877 {
1878 	const struct bpf_prog *prog = filp->private_data;
1879 	char prog_tag[sizeof(prog->tag) * 2 + 1] = { };
1880 	struct bpf_prog_kstats stats;
1881 
1882 	bpf_prog_get_stats(prog, &stats);
1883 	bin2hex(prog_tag, prog->tag, sizeof(prog->tag));
1884 	seq_printf(m,
1885 		   "prog_type:\t%u\n"
1886 		   "prog_jited:\t%u\n"
1887 		   "prog_tag:\t%s\n"
1888 		   "memlock:\t%llu\n"
1889 		   "prog_id:\t%u\n"
1890 		   "run_time_ns:\t%llu\n"
1891 		   "run_cnt:\t%llu\n"
1892 		   "recursion_misses:\t%llu\n"
1893 		   "verified_insns:\t%u\n",
1894 		   prog->type,
1895 		   prog->jited,
1896 		   prog_tag,
1897 		   prog->pages * 1ULL << PAGE_SHIFT,
1898 		   prog->aux->id,
1899 		   stats.nsecs,
1900 		   stats.cnt,
1901 		   stats.misses,
1902 		   prog->aux->verified_insns);
1903 }
1904 #endif
1905 
1906 const struct file_operations bpf_prog_fops = {
1907 #ifdef CONFIG_PROC_FS
1908 	.show_fdinfo	= bpf_prog_show_fdinfo,
1909 #endif
1910 	.release	= bpf_prog_release,
1911 	.read		= bpf_dummy_read,
1912 	.write		= bpf_dummy_write,
1913 };
1914 
1915 int bpf_prog_new_fd(struct bpf_prog *prog)
1916 {
1917 	int ret;
1918 
1919 	ret = security_bpf_prog(prog);
1920 	if (ret < 0)
1921 		return ret;
1922 
1923 	return anon_inode_getfd("bpf-prog", &bpf_prog_fops, prog,
1924 				O_RDWR | O_CLOEXEC);
1925 }
1926 
1927 static struct bpf_prog *____bpf_prog_get(struct fd f)
1928 {
1929 	if (!f.file)
1930 		return ERR_PTR(-EBADF);
1931 	if (f.file->f_op != &bpf_prog_fops) {
1932 		fdput(f);
1933 		return ERR_PTR(-EINVAL);
1934 	}
1935 
1936 	return f.file->private_data;
1937 }
1938 
1939 void bpf_prog_add(struct bpf_prog *prog, int i)
1940 {
1941 	atomic64_add(i, &prog->aux->refcnt);
1942 }
1943 EXPORT_SYMBOL_GPL(bpf_prog_add);
1944 
1945 void bpf_prog_sub(struct bpf_prog *prog, int i)
1946 {
1947 	/* Only to be used for undoing previous bpf_prog_add() in some
1948 	 * error path. We still know that another entity in our call
1949 	 * path holds a reference to the program, thus atomic_sub() can
1950 	 * be safely used in such cases!
1951 	 */
1952 	WARN_ON(atomic64_sub_return(i, &prog->aux->refcnt) == 0);
1953 }
1954 EXPORT_SYMBOL_GPL(bpf_prog_sub);
1955 
1956 void bpf_prog_inc(struct bpf_prog *prog)
1957 {
1958 	atomic64_inc(&prog->aux->refcnt);
1959 }
1960 EXPORT_SYMBOL_GPL(bpf_prog_inc);
1961 
1962 /* prog_idr_lock should have been held */
1963 struct bpf_prog *bpf_prog_inc_not_zero(struct bpf_prog *prog)
1964 {
1965 	int refold;
1966 
1967 	refold = atomic64_fetch_add_unless(&prog->aux->refcnt, 1, 0);
1968 
1969 	if (!refold)
1970 		return ERR_PTR(-ENOENT);
1971 
1972 	return prog;
1973 }
1974 EXPORT_SYMBOL_GPL(bpf_prog_inc_not_zero);
1975 
1976 bool bpf_prog_get_ok(struct bpf_prog *prog,
1977 			    enum bpf_prog_type *attach_type, bool attach_drv)
1978 {
1979 	/* not an attachment, just a refcount inc, always allow */
1980 	if (!attach_type)
1981 		return true;
1982 
1983 	if (prog->type != *attach_type)
1984 		return false;
1985 	if (bpf_prog_is_dev_bound(prog->aux) && !attach_drv)
1986 		return false;
1987 
1988 	return true;
1989 }
1990 
1991 static struct bpf_prog *__bpf_prog_get(u32 ufd, enum bpf_prog_type *attach_type,
1992 				       bool attach_drv)
1993 {
1994 	struct fd f = fdget(ufd);
1995 	struct bpf_prog *prog;
1996 
1997 	prog = ____bpf_prog_get(f);
1998 	if (IS_ERR(prog))
1999 		return prog;
2000 	if (!bpf_prog_get_ok(prog, attach_type, attach_drv)) {
2001 		prog = ERR_PTR(-EINVAL);
2002 		goto out;
2003 	}
2004 
2005 	bpf_prog_inc(prog);
2006 out:
2007 	fdput(f);
2008 	return prog;
2009 }
2010 
2011 struct bpf_prog *bpf_prog_get(u32 ufd)
2012 {
2013 	return __bpf_prog_get(ufd, NULL, false);
2014 }
2015 
2016 struct bpf_prog *bpf_prog_get_type_dev(u32 ufd, enum bpf_prog_type type,
2017 				       bool attach_drv)
2018 {
2019 	return __bpf_prog_get(ufd, &type, attach_drv);
2020 }
2021 EXPORT_SYMBOL_GPL(bpf_prog_get_type_dev);
2022 
2023 /* Initially all BPF programs could be loaded w/o specifying
2024  * expected_attach_type. Later for some of them specifying expected_attach_type
2025  * at load time became required so that program could be validated properly.
2026  * Programs of types that are allowed to be loaded both w/ and w/o (for
2027  * backward compatibility) expected_attach_type, should have the default attach
2028  * type assigned to expected_attach_type for the latter case, so that it can be
2029  * validated later at attach time.
2030  *
2031  * bpf_prog_load_fixup_attach_type() sets expected_attach_type in @attr if
2032  * prog type requires it but has some attach types that have to be backward
2033  * compatible.
2034  */
2035 static void bpf_prog_load_fixup_attach_type(union bpf_attr *attr)
2036 {
2037 	switch (attr->prog_type) {
2038 	case BPF_PROG_TYPE_CGROUP_SOCK:
2039 		/* Unfortunately BPF_ATTACH_TYPE_UNSPEC enumeration doesn't
2040 		 * exist so checking for non-zero is the way to go here.
2041 		 */
2042 		if (!attr->expected_attach_type)
2043 			attr->expected_attach_type =
2044 				BPF_CGROUP_INET_SOCK_CREATE;
2045 		break;
2046 	case BPF_PROG_TYPE_SK_REUSEPORT:
2047 		if (!attr->expected_attach_type)
2048 			attr->expected_attach_type =
2049 				BPF_SK_REUSEPORT_SELECT;
2050 		break;
2051 	}
2052 }
2053 
2054 static int
2055 bpf_prog_load_check_attach(enum bpf_prog_type prog_type,
2056 			   enum bpf_attach_type expected_attach_type,
2057 			   struct btf *attach_btf, u32 btf_id,
2058 			   struct bpf_prog *dst_prog)
2059 {
2060 	if (btf_id) {
2061 		if (btf_id > BTF_MAX_TYPE)
2062 			return -EINVAL;
2063 
2064 		if (!attach_btf && !dst_prog)
2065 			return -EINVAL;
2066 
2067 		switch (prog_type) {
2068 		case BPF_PROG_TYPE_TRACING:
2069 		case BPF_PROG_TYPE_LSM:
2070 		case BPF_PROG_TYPE_STRUCT_OPS:
2071 		case BPF_PROG_TYPE_EXT:
2072 			break;
2073 		default:
2074 			return -EINVAL;
2075 		}
2076 	}
2077 
2078 	if (attach_btf && (!btf_id || dst_prog))
2079 		return -EINVAL;
2080 
2081 	if (dst_prog && prog_type != BPF_PROG_TYPE_TRACING &&
2082 	    prog_type != BPF_PROG_TYPE_EXT)
2083 		return -EINVAL;
2084 
2085 	switch (prog_type) {
2086 	case BPF_PROG_TYPE_CGROUP_SOCK:
2087 		switch (expected_attach_type) {
2088 		case BPF_CGROUP_INET_SOCK_CREATE:
2089 		case BPF_CGROUP_INET_SOCK_RELEASE:
2090 		case BPF_CGROUP_INET4_POST_BIND:
2091 		case BPF_CGROUP_INET6_POST_BIND:
2092 			return 0;
2093 		default:
2094 			return -EINVAL;
2095 		}
2096 	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
2097 		switch (expected_attach_type) {
2098 		case BPF_CGROUP_INET4_BIND:
2099 		case BPF_CGROUP_INET6_BIND:
2100 		case BPF_CGROUP_INET4_CONNECT:
2101 		case BPF_CGROUP_INET6_CONNECT:
2102 		case BPF_CGROUP_INET4_GETPEERNAME:
2103 		case BPF_CGROUP_INET6_GETPEERNAME:
2104 		case BPF_CGROUP_INET4_GETSOCKNAME:
2105 		case BPF_CGROUP_INET6_GETSOCKNAME:
2106 		case BPF_CGROUP_UDP4_SENDMSG:
2107 		case BPF_CGROUP_UDP6_SENDMSG:
2108 		case BPF_CGROUP_UDP4_RECVMSG:
2109 		case BPF_CGROUP_UDP6_RECVMSG:
2110 			return 0;
2111 		default:
2112 			return -EINVAL;
2113 		}
2114 	case BPF_PROG_TYPE_CGROUP_SKB:
2115 		switch (expected_attach_type) {
2116 		case BPF_CGROUP_INET_INGRESS:
2117 		case BPF_CGROUP_INET_EGRESS:
2118 			return 0;
2119 		default:
2120 			return -EINVAL;
2121 		}
2122 	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
2123 		switch (expected_attach_type) {
2124 		case BPF_CGROUP_SETSOCKOPT:
2125 		case BPF_CGROUP_GETSOCKOPT:
2126 			return 0;
2127 		default:
2128 			return -EINVAL;
2129 		}
2130 	case BPF_PROG_TYPE_SK_LOOKUP:
2131 		if (expected_attach_type == BPF_SK_LOOKUP)
2132 			return 0;
2133 		return -EINVAL;
2134 	case BPF_PROG_TYPE_SK_REUSEPORT:
2135 		switch (expected_attach_type) {
2136 		case BPF_SK_REUSEPORT_SELECT:
2137 		case BPF_SK_REUSEPORT_SELECT_OR_MIGRATE:
2138 			return 0;
2139 		default:
2140 			return -EINVAL;
2141 		}
2142 	case BPF_PROG_TYPE_SYSCALL:
2143 	case BPF_PROG_TYPE_EXT:
2144 		if (expected_attach_type)
2145 			return -EINVAL;
2146 		fallthrough;
2147 	default:
2148 		return 0;
2149 	}
2150 }
2151 
2152 static bool is_net_admin_prog_type(enum bpf_prog_type prog_type)
2153 {
2154 	switch (prog_type) {
2155 	case BPF_PROG_TYPE_SCHED_CLS:
2156 	case BPF_PROG_TYPE_SCHED_ACT:
2157 	case BPF_PROG_TYPE_XDP:
2158 	case BPF_PROG_TYPE_LWT_IN:
2159 	case BPF_PROG_TYPE_LWT_OUT:
2160 	case BPF_PROG_TYPE_LWT_XMIT:
2161 	case BPF_PROG_TYPE_LWT_SEG6LOCAL:
2162 	case BPF_PROG_TYPE_SK_SKB:
2163 	case BPF_PROG_TYPE_SK_MSG:
2164 	case BPF_PROG_TYPE_LIRC_MODE2:
2165 	case BPF_PROG_TYPE_FLOW_DISSECTOR:
2166 	case BPF_PROG_TYPE_CGROUP_DEVICE:
2167 	case BPF_PROG_TYPE_CGROUP_SOCK:
2168 	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
2169 	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
2170 	case BPF_PROG_TYPE_CGROUP_SYSCTL:
2171 	case BPF_PROG_TYPE_SOCK_OPS:
2172 	case BPF_PROG_TYPE_EXT: /* extends any prog */
2173 		return true;
2174 	case BPF_PROG_TYPE_CGROUP_SKB:
2175 		/* always unpriv */
2176 	case BPF_PROG_TYPE_SK_REUSEPORT:
2177 		/* equivalent to SOCKET_FILTER. need CAP_BPF only */
2178 	default:
2179 		return false;
2180 	}
2181 }
2182 
2183 static bool is_perfmon_prog_type(enum bpf_prog_type prog_type)
2184 {
2185 	switch (prog_type) {
2186 	case BPF_PROG_TYPE_KPROBE:
2187 	case BPF_PROG_TYPE_TRACEPOINT:
2188 	case BPF_PROG_TYPE_PERF_EVENT:
2189 	case BPF_PROG_TYPE_RAW_TRACEPOINT:
2190 	case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE:
2191 	case BPF_PROG_TYPE_TRACING:
2192 	case BPF_PROG_TYPE_LSM:
2193 	case BPF_PROG_TYPE_STRUCT_OPS: /* has access to struct sock */
2194 	case BPF_PROG_TYPE_EXT: /* extends any prog */
2195 		return true;
2196 	default:
2197 		return false;
2198 	}
2199 }
2200 
2201 /* last field in 'union bpf_attr' used by this command */
2202 #define	BPF_PROG_LOAD_LAST_FIELD core_relo_rec_size
2203 
2204 static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr)
2205 {
2206 	enum bpf_prog_type type = attr->prog_type;
2207 	struct bpf_prog *prog, *dst_prog = NULL;
2208 	struct btf *attach_btf = NULL;
2209 	int err;
2210 	char license[128];
2211 	bool is_gpl;
2212 
2213 	if (CHECK_ATTR(BPF_PROG_LOAD))
2214 		return -EINVAL;
2215 
2216 	if (attr->prog_flags & ~(BPF_F_STRICT_ALIGNMENT |
2217 				 BPF_F_ANY_ALIGNMENT |
2218 				 BPF_F_TEST_STATE_FREQ |
2219 				 BPF_F_SLEEPABLE |
2220 				 BPF_F_TEST_RND_HI32))
2221 		return -EINVAL;
2222 
2223 	if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) &&
2224 	    (attr->prog_flags & BPF_F_ANY_ALIGNMENT) &&
2225 	    !bpf_capable())
2226 		return -EPERM;
2227 
2228 	/* copy eBPF program license from user space */
2229 	if (strncpy_from_bpfptr(license,
2230 				make_bpfptr(attr->license, uattr.is_kernel),
2231 				sizeof(license) - 1) < 0)
2232 		return -EFAULT;
2233 	license[sizeof(license) - 1] = 0;
2234 
2235 	/* eBPF programs must be GPL compatible to use GPL-ed functions */
2236 	is_gpl = license_is_gpl_compatible(license);
2237 
2238 	if (attr->insn_cnt == 0 ||
2239 	    attr->insn_cnt > (bpf_capable() ? BPF_COMPLEXITY_LIMIT_INSNS : BPF_MAXINSNS))
2240 		return -E2BIG;
2241 	if (type != BPF_PROG_TYPE_SOCKET_FILTER &&
2242 	    type != BPF_PROG_TYPE_CGROUP_SKB &&
2243 	    !bpf_capable())
2244 		return -EPERM;
2245 
2246 	if (is_net_admin_prog_type(type) && !capable(CAP_NET_ADMIN) && !capable(CAP_SYS_ADMIN))
2247 		return -EPERM;
2248 	if (is_perfmon_prog_type(type) && !perfmon_capable())
2249 		return -EPERM;
2250 
2251 	/* attach_prog_fd/attach_btf_obj_fd can specify fd of either bpf_prog
2252 	 * or btf, we need to check which one it is
2253 	 */
2254 	if (attr->attach_prog_fd) {
2255 		dst_prog = bpf_prog_get(attr->attach_prog_fd);
2256 		if (IS_ERR(dst_prog)) {
2257 			dst_prog = NULL;
2258 			attach_btf = btf_get_by_fd(attr->attach_btf_obj_fd);
2259 			if (IS_ERR(attach_btf))
2260 				return -EINVAL;
2261 			if (!btf_is_kernel(attach_btf)) {
2262 				/* attaching through specifying bpf_prog's BTF
2263 				 * objects directly might be supported eventually
2264 				 */
2265 				btf_put(attach_btf);
2266 				return -ENOTSUPP;
2267 			}
2268 		}
2269 	} else if (attr->attach_btf_id) {
2270 		/* fall back to vmlinux BTF, if BTF type ID is specified */
2271 		attach_btf = bpf_get_btf_vmlinux();
2272 		if (IS_ERR(attach_btf))
2273 			return PTR_ERR(attach_btf);
2274 		if (!attach_btf)
2275 			return -EINVAL;
2276 		btf_get(attach_btf);
2277 	}
2278 
2279 	bpf_prog_load_fixup_attach_type(attr);
2280 	if (bpf_prog_load_check_attach(type, attr->expected_attach_type,
2281 				       attach_btf, attr->attach_btf_id,
2282 				       dst_prog)) {
2283 		if (dst_prog)
2284 			bpf_prog_put(dst_prog);
2285 		if (attach_btf)
2286 			btf_put(attach_btf);
2287 		return -EINVAL;
2288 	}
2289 
2290 	/* plain bpf_prog allocation */
2291 	prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER);
2292 	if (!prog) {
2293 		if (dst_prog)
2294 			bpf_prog_put(dst_prog);
2295 		if (attach_btf)
2296 			btf_put(attach_btf);
2297 		return -ENOMEM;
2298 	}
2299 
2300 	prog->expected_attach_type = attr->expected_attach_type;
2301 	prog->aux->attach_btf = attach_btf;
2302 	prog->aux->attach_btf_id = attr->attach_btf_id;
2303 	prog->aux->dst_prog = dst_prog;
2304 	prog->aux->offload_requested = !!attr->prog_ifindex;
2305 	prog->aux->sleepable = attr->prog_flags & BPF_F_SLEEPABLE;
2306 
2307 	err = security_bpf_prog_alloc(prog->aux);
2308 	if (err)
2309 		goto free_prog;
2310 
2311 	prog->aux->user = get_current_user();
2312 	prog->len = attr->insn_cnt;
2313 
2314 	err = -EFAULT;
2315 	if (copy_from_bpfptr(prog->insns,
2316 			     make_bpfptr(attr->insns, uattr.is_kernel),
2317 			     bpf_prog_insn_size(prog)) != 0)
2318 		goto free_prog_sec;
2319 
2320 	prog->orig_prog = NULL;
2321 	prog->jited = 0;
2322 
2323 	atomic64_set(&prog->aux->refcnt, 1);
2324 	prog->gpl_compatible = is_gpl ? 1 : 0;
2325 
2326 	if (bpf_prog_is_dev_bound(prog->aux)) {
2327 		err = bpf_prog_offload_init(prog, attr);
2328 		if (err)
2329 			goto free_prog_sec;
2330 	}
2331 
2332 	/* find program type: socket_filter vs tracing_filter */
2333 	err = find_prog_type(type, prog);
2334 	if (err < 0)
2335 		goto free_prog_sec;
2336 
2337 	prog->aux->load_time = ktime_get_boottime_ns();
2338 	err = bpf_obj_name_cpy(prog->aux->name, attr->prog_name,
2339 			       sizeof(attr->prog_name));
2340 	if (err < 0)
2341 		goto free_prog_sec;
2342 
2343 	/* run eBPF verifier */
2344 	err = bpf_check(&prog, attr, uattr);
2345 	if (err < 0)
2346 		goto free_used_maps;
2347 
2348 	prog = bpf_prog_select_runtime(prog, &err);
2349 	if (err < 0)
2350 		goto free_used_maps;
2351 
2352 	err = bpf_prog_alloc_id(prog);
2353 	if (err)
2354 		goto free_used_maps;
2355 
2356 	/* Upon success of bpf_prog_alloc_id(), the BPF prog is
2357 	 * effectively publicly exposed. However, retrieving via
2358 	 * bpf_prog_get_fd_by_id() will take another reference,
2359 	 * therefore it cannot be gone underneath us.
2360 	 *
2361 	 * Only for the time /after/ successful bpf_prog_new_fd()
2362 	 * and before returning to userspace, we might just hold
2363 	 * one reference and any parallel close on that fd could
2364 	 * rip everything out. Hence, below notifications must
2365 	 * happen before bpf_prog_new_fd().
2366 	 *
2367 	 * Also, any failure handling from this point onwards must
2368 	 * be using bpf_prog_put() given the program is exposed.
2369 	 */
2370 	bpf_prog_kallsyms_add(prog);
2371 	perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_LOAD, 0);
2372 	bpf_audit_prog(prog, BPF_AUDIT_LOAD);
2373 
2374 	err = bpf_prog_new_fd(prog);
2375 	if (err < 0)
2376 		bpf_prog_put(prog);
2377 	return err;
2378 
2379 free_used_maps:
2380 	/* In case we have subprogs, we need to wait for a grace
2381 	 * period before we can tear down JIT memory since symbols
2382 	 * are already exposed under kallsyms.
2383 	 */
2384 	__bpf_prog_put_noref(prog, prog->aux->func_cnt);
2385 	return err;
2386 free_prog_sec:
2387 	free_uid(prog->aux->user);
2388 	security_bpf_prog_free(prog->aux);
2389 free_prog:
2390 	if (prog->aux->attach_btf)
2391 		btf_put(prog->aux->attach_btf);
2392 	bpf_prog_free(prog);
2393 	return err;
2394 }
2395 
2396 #define BPF_OBJ_LAST_FIELD file_flags
2397 
2398 static int bpf_obj_pin(const union bpf_attr *attr)
2399 {
2400 	if (CHECK_ATTR(BPF_OBJ) || attr->file_flags != 0)
2401 		return -EINVAL;
2402 
2403 	return bpf_obj_pin_user(attr->bpf_fd, u64_to_user_ptr(attr->pathname));
2404 }
2405 
2406 static int bpf_obj_get(const union bpf_attr *attr)
2407 {
2408 	if (CHECK_ATTR(BPF_OBJ) || attr->bpf_fd != 0 ||
2409 	    attr->file_flags & ~BPF_OBJ_FLAG_MASK)
2410 		return -EINVAL;
2411 
2412 	return bpf_obj_get_user(u64_to_user_ptr(attr->pathname),
2413 				attr->file_flags);
2414 }
2415 
2416 void bpf_link_init(struct bpf_link *link, enum bpf_link_type type,
2417 		   const struct bpf_link_ops *ops, struct bpf_prog *prog)
2418 {
2419 	atomic64_set(&link->refcnt, 1);
2420 	link->type = type;
2421 	link->id = 0;
2422 	link->ops = ops;
2423 	link->prog = prog;
2424 }
2425 
2426 static void bpf_link_free_id(int id)
2427 {
2428 	if (!id)
2429 		return;
2430 
2431 	spin_lock_bh(&link_idr_lock);
2432 	idr_remove(&link_idr, id);
2433 	spin_unlock_bh(&link_idr_lock);
2434 }
2435 
2436 /* Clean up bpf_link and corresponding anon_inode file and FD. After
2437  * anon_inode is created, bpf_link can't be just kfree()'d due to deferred
2438  * anon_inode's release() call. This helper marksbpf_link as
2439  * defunct, releases anon_inode file and puts reserved FD. bpf_prog's refcnt
2440  * is not decremented, it's the responsibility of a calling code that failed
2441  * to complete bpf_link initialization.
2442  */
2443 void bpf_link_cleanup(struct bpf_link_primer *primer)
2444 {
2445 	primer->link->prog = NULL;
2446 	bpf_link_free_id(primer->id);
2447 	fput(primer->file);
2448 	put_unused_fd(primer->fd);
2449 }
2450 
2451 void bpf_link_inc(struct bpf_link *link)
2452 {
2453 	atomic64_inc(&link->refcnt);
2454 }
2455 
2456 /* bpf_link_free is guaranteed to be called from process context */
2457 static void bpf_link_free(struct bpf_link *link)
2458 {
2459 	bpf_link_free_id(link->id);
2460 	if (link->prog) {
2461 		/* detach BPF program, clean up used resources */
2462 		link->ops->release(link);
2463 		bpf_prog_put(link->prog);
2464 	}
2465 	/* free bpf_link and its containing memory */
2466 	link->ops->dealloc(link);
2467 }
2468 
2469 static void bpf_link_put_deferred(struct work_struct *work)
2470 {
2471 	struct bpf_link *link = container_of(work, struct bpf_link, work);
2472 
2473 	bpf_link_free(link);
2474 }
2475 
2476 /* bpf_link_put can be called from atomic context, but ensures that resources
2477  * are freed from process context
2478  */
2479 void bpf_link_put(struct bpf_link *link)
2480 {
2481 	if (!atomic64_dec_and_test(&link->refcnt))
2482 		return;
2483 
2484 	if (in_atomic()) {
2485 		INIT_WORK(&link->work, bpf_link_put_deferred);
2486 		schedule_work(&link->work);
2487 	} else {
2488 		bpf_link_free(link);
2489 	}
2490 }
2491 
2492 static int bpf_link_release(struct inode *inode, struct file *filp)
2493 {
2494 	struct bpf_link *link = filp->private_data;
2495 
2496 	bpf_link_put(link);
2497 	return 0;
2498 }
2499 
2500 #ifdef CONFIG_PROC_FS
2501 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type)
2502 #define BPF_MAP_TYPE(_id, _ops)
2503 #define BPF_LINK_TYPE(_id, _name) [_id] = #_name,
2504 static const char *bpf_link_type_strs[] = {
2505 	[BPF_LINK_TYPE_UNSPEC] = "<invalid>",
2506 #include <linux/bpf_types.h>
2507 };
2508 #undef BPF_PROG_TYPE
2509 #undef BPF_MAP_TYPE
2510 #undef BPF_LINK_TYPE
2511 
2512 static void bpf_link_show_fdinfo(struct seq_file *m, struct file *filp)
2513 {
2514 	const struct bpf_link *link = filp->private_data;
2515 	const struct bpf_prog *prog = link->prog;
2516 	char prog_tag[sizeof(prog->tag) * 2 + 1] = { };
2517 
2518 	bin2hex(prog_tag, prog->tag, sizeof(prog->tag));
2519 	seq_printf(m,
2520 		   "link_type:\t%s\n"
2521 		   "link_id:\t%u\n"
2522 		   "prog_tag:\t%s\n"
2523 		   "prog_id:\t%u\n",
2524 		   bpf_link_type_strs[link->type],
2525 		   link->id,
2526 		   prog_tag,
2527 		   prog->aux->id);
2528 	if (link->ops->show_fdinfo)
2529 		link->ops->show_fdinfo(link, m);
2530 }
2531 #endif
2532 
2533 static const struct file_operations bpf_link_fops = {
2534 #ifdef CONFIG_PROC_FS
2535 	.show_fdinfo	= bpf_link_show_fdinfo,
2536 #endif
2537 	.release	= bpf_link_release,
2538 	.read		= bpf_dummy_read,
2539 	.write		= bpf_dummy_write,
2540 };
2541 
2542 static int bpf_link_alloc_id(struct bpf_link *link)
2543 {
2544 	int id;
2545 
2546 	idr_preload(GFP_KERNEL);
2547 	spin_lock_bh(&link_idr_lock);
2548 	id = idr_alloc_cyclic(&link_idr, link, 1, INT_MAX, GFP_ATOMIC);
2549 	spin_unlock_bh(&link_idr_lock);
2550 	idr_preload_end();
2551 
2552 	return id;
2553 }
2554 
2555 /* Prepare bpf_link to be exposed to user-space by allocating anon_inode file,
2556  * reserving unused FD and allocating ID from link_idr. This is to be paired
2557  * with bpf_link_settle() to install FD and ID and expose bpf_link to
2558  * user-space, if bpf_link is successfully attached. If not, bpf_link and
2559  * pre-allocated resources are to be freed with bpf_cleanup() call. All the
2560  * transient state is passed around in struct bpf_link_primer.
2561  * This is preferred way to create and initialize bpf_link, especially when
2562  * there are complicated and expensive operations inbetween creating bpf_link
2563  * itself and attaching it to BPF hook. By using bpf_link_prime() and
2564  * bpf_link_settle() kernel code using bpf_link doesn't have to perform
2565  * expensive (and potentially failing) roll back operations in a rare case
2566  * that file, FD, or ID can't be allocated.
2567  */
2568 int bpf_link_prime(struct bpf_link *link, struct bpf_link_primer *primer)
2569 {
2570 	struct file *file;
2571 	int fd, id;
2572 
2573 	fd = get_unused_fd_flags(O_CLOEXEC);
2574 	if (fd < 0)
2575 		return fd;
2576 
2577 
2578 	id = bpf_link_alloc_id(link);
2579 	if (id < 0) {
2580 		put_unused_fd(fd);
2581 		return id;
2582 	}
2583 
2584 	file = anon_inode_getfile("bpf_link", &bpf_link_fops, link, O_CLOEXEC);
2585 	if (IS_ERR(file)) {
2586 		bpf_link_free_id(id);
2587 		put_unused_fd(fd);
2588 		return PTR_ERR(file);
2589 	}
2590 
2591 	primer->link = link;
2592 	primer->file = file;
2593 	primer->fd = fd;
2594 	primer->id = id;
2595 	return 0;
2596 }
2597 
2598 int bpf_link_settle(struct bpf_link_primer *primer)
2599 {
2600 	/* make bpf_link fetchable by ID */
2601 	spin_lock_bh(&link_idr_lock);
2602 	primer->link->id = primer->id;
2603 	spin_unlock_bh(&link_idr_lock);
2604 	/* make bpf_link fetchable by FD */
2605 	fd_install(primer->fd, primer->file);
2606 	/* pass through installed FD */
2607 	return primer->fd;
2608 }
2609 
2610 int bpf_link_new_fd(struct bpf_link *link)
2611 {
2612 	return anon_inode_getfd("bpf-link", &bpf_link_fops, link, O_CLOEXEC);
2613 }
2614 
2615 struct bpf_link *bpf_link_get_from_fd(u32 ufd)
2616 {
2617 	struct fd f = fdget(ufd);
2618 	struct bpf_link *link;
2619 
2620 	if (!f.file)
2621 		return ERR_PTR(-EBADF);
2622 	if (f.file->f_op != &bpf_link_fops) {
2623 		fdput(f);
2624 		return ERR_PTR(-EINVAL);
2625 	}
2626 
2627 	link = f.file->private_data;
2628 	bpf_link_inc(link);
2629 	fdput(f);
2630 
2631 	return link;
2632 }
2633 
2634 struct bpf_tracing_link {
2635 	struct bpf_link link;
2636 	enum bpf_attach_type attach_type;
2637 	struct bpf_trampoline *trampoline;
2638 	struct bpf_prog *tgt_prog;
2639 };
2640 
2641 static void bpf_tracing_link_release(struct bpf_link *link)
2642 {
2643 	struct bpf_tracing_link *tr_link =
2644 		container_of(link, struct bpf_tracing_link, link);
2645 
2646 	WARN_ON_ONCE(bpf_trampoline_unlink_prog(link->prog,
2647 						tr_link->trampoline));
2648 
2649 	bpf_trampoline_put(tr_link->trampoline);
2650 
2651 	/* tgt_prog is NULL if target is a kernel function */
2652 	if (tr_link->tgt_prog)
2653 		bpf_prog_put(tr_link->tgt_prog);
2654 }
2655 
2656 static void bpf_tracing_link_dealloc(struct bpf_link *link)
2657 {
2658 	struct bpf_tracing_link *tr_link =
2659 		container_of(link, struct bpf_tracing_link, link);
2660 
2661 	kfree(tr_link);
2662 }
2663 
2664 static void bpf_tracing_link_show_fdinfo(const struct bpf_link *link,
2665 					 struct seq_file *seq)
2666 {
2667 	struct bpf_tracing_link *tr_link =
2668 		container_of(link, struct bpf_tracing_link, link);
2669 
2670 	seq_printf(seq,
2671 		   "attach_type:\t%d\n",
2672 		   tr_link->attach_type);
2673 }
2674 
2675 static int bpf_tracing_link_fill_link_info(const struct bpf_link *link,
2676 					   struct bpf_link_info *info)
2677 {
2678 	struct bpf_tracing_link *tr_link =
2679 		container_of(link, struct bpf_tracing_link, link);
2680 
2681 	info->tracing.attach_type = tr_link->attach_type;
2682 	bpf_trampoline_unpack_key(tr_link->trampoline->key,
2683 				  &info->tracing.target_obj_id,
2684 				  &info->tracing.target_btf_id);
2685 
2686 	return 0;
2687 }
2688 
2689 static const struct bpf_link_ops bpf_tracing_link_lops = {
2690 	.release = bpf_tracing_link_release,
2691 	.dealloc = bpf_tracing_link_dealloc,
2692 	.show_fdinfo = bpf_tracing_link_show_fdinfo,
2693 	.fill_link_info = bpf_tracing_link_fill_link_info,
2694 };
2695 
2696 static int bpf_tracing_prog_attach(struct bpf_prog *prog,
2697 				   int tgt_prog_fd,
2698 				   u32 btf_id)
2699 {
2700 	struct bpf_link_primer link_primer;
2701 	struct bpf_prog *tgt_prog = NULL;
2702 	struct bpf_trampoline *tr = NULL;
2703 	struct bpf_tracing_link *link;
2704 	u64 key = 0;
2705 	int err;
2706 
2707 	switch (prog->type) {
2708 	case BPF_PROG_TYPE_TRACING:
2709 		if (prog->expected_attach_type != BPF_TRACE_FENTRY &&
2710 		    prog->expected_attach_type != BPF_TRACE_FEXIT &&
2711 		    prog->expected_attach_type != BPF_MODIFY_RETURN) {
2712 			err = -EINVAL;
2713 			goto out_put_prog;
2714 		}
2715 		break;
2716 	case BPF_PROG_TYPE_EXT:
2717 		if (prog->expected_attach_type != 0) {
2718 			err = -EINVAL;
2719 			goto out_put_prog;
2720 		}
2721 		break;
2722 	case BPF_PROG_TYPE_LSM:
2723 		if (prog->expected_attach_type != BPF_LSM_MAC) {
2724 			err = -EINVAL;
2725 			goto out_put_prog;
2726 		}
2727 		break;
2728 	default:
2729 		err = -EINVAL;
2730 		goto out_put_prog;
2731 	}
2732 
2733 	if (!!tgt_prog_fd != !!btf_id) {
2734 		err = -EINVAL;
2735 		goto out_put_prog;
2736 	}
2737 
2738 	if (tgt_prog_fd) {
2739 		/* For now we only allow new targets for BPF_PROG_TYPE_EXT */
2740 		if (prog->type != BPF_PROG_TYPE_EXT) {
2741 			err = -EINVAL;
2742 			goto out_put_prog;
2743 		}
2744 
2745 		tgt_prog = bpf_prog_get(tgt_prog_fd);
2746 		if (IS_ERR(tgt_prog)) {
2747 			err = PTR_ERR(tgt_prog);
2748 			tgt_prog = NULL;
2749 			goto out_put_prog;
2750 		}
2751 
2752 		key = bpf_trampoline_compute_key(tgt_prog, NULL, btf_id);
2753 	}
2754 
2755 	link = kzalloc(sizeof(*link), GFP_USER);
2756 	if (!link) {
2757 		err = -ENOMEM;
2758 		goto out_put_prog;
2759 	}
2760 	bpf_link_init(&link->link, BPF_LINK_TYPE_TRACING,
2761 		      &bpf_tracing_link_lops, prog);
2762 	link->attach_type = prog->expected_attach_type;
2763 
2764 	mutex_lock(&prog->aux->dst_mutex);
2765 
2766 	/* There are a few possible cases here:
2767 	 *
2768 	 * - if prog->aux->dst_trampoline is set, the program was just loaded
2769 	 *   and not yet attached to anything, so we can use the values stored
2770 	 *   in prog->aux
2771 	 *
2772 	 * - if prog->aux->dst_trampoline is NULL, the program has already been
2773          *   attached to a target and its initial target was cleared (below)
2774 	 *
2775 	 * - if tgt_prog != NULL, the caller specified tgt_prog_fd +
2776 	 *   target_btf_id using the link_create API.
2777 	 *
2778 	 * - if tgt_prog == NULL when this function was called using the old
2779 	 *   raw_tracepoint_open API, and we need a target from prog->aux
2780 	 *
2781 	 * - if prog->aux->dst_trampoline and tgt_prog is NULL, the program
2782 	 *   was detached and is going for re-attachment.
2783 	 */
2784 	if (!prog->aux->dst_trampoline && !tgt_prog) {
2785 		/*
2786 		 * Allow re-attach for TRACING and LSM programs. If it's
2787 		 * currently linked, bpf_trampoline_link_prog will fail.
2788 		 * EXT programs need to specify tgt_prog_fd, so they
2789 		 * re-attach in separate code path.
2790 		 */
2791 		if (prog->type != BPF_PROG_TYPE_TRACING &&
2792 		    prog->type != BPF_PROG_TYPE_LSM) {
2793 			err = -EINVAL;
2794 			goto out_unlock;
2795 		}
2796 		btf_id = prog->aux->attach_btf_id;
2797 		key = bpf_trampoline_compute_key(NULL, prog->aux->attach_btf, btf_id);
2798 	}
2799 
2800 	if (!prog->aux->dst_trampoline ||
2801 	    (key && key != prog->aux->dst_trampoline->key)) {
2802 		/* If there is no saved target, or the specified target is
2803 		 * different from the destination specified at load time, we
2804 		 * need a new trampoline and a check for compatibility
2805 		 */
2806 		struct bpf_attach_target_info tgt_info = {};
2807 
2808 		err = bpf_check_attach_target(NULL, prog, tgt_prog, btf_id,
2809 					      &tgt_info);
2810 		if (err)
2811 			goto out_unlock;
2812 
2813 		tr = bpf_trampoline_get(key, &tgt_info);
2814 		if (!tr) {
2815 			err = -ENOMEM;
2816 			goto out_unlock;
2817 		}
2818 	} else {
2819 		/* The caller didn't specify a target, or the target was the
2820 		 * same as the destination supplied during program load. This
2821 		 * means we can reuse the trampoline and reference from program
2822 		 * load time, and there is no need to allocate a new one. This
2823 		 * can only happen once for any program, as the saved values in
2824 		 * prog->aux are cleared below.
2825 		 */
2826 		tr = prog->aux->dst_trampoline;
2827 		tgt_prog = prog->aux->dst_prog;
2828 	}
2829 
2830 	err = bpf_link_prime(&link->link, &link_primer);
2831 	if (err)
2832 		goto out_unlock;
2833 
2834 	err = bpf_trampoline_link_prog(prog, tr);
2835 	if (err) {
2836 		bpf_link_cleanup(&link_primer);
2837 		link = NULL;
2838 		goto out_unlock;
2839 	}
2840 
2841 	link->tgt_prog = tgt_prog;
2842 	link->trampoline = tr;
2843 
2844 	/* Always clear the trampoline and target prog from prog->aux to make
2845 	 * sure the original attach destination is not kept alive after a
2846 	 * program is (re-)attached to another target.
2847 	 */
2848 	if (prog->aux->dst_prog &&
2849 	    (tgt_prog_fd || tr != prog->aux->dst_trampoline))
2850 		/* got extra prog ref from syscall, or attaching to different prog */
2851 		bpf_prog_put(prog->aux->dst_prog);
2852 	if (prog->aux->dst_trampoline && tr != prog->aux->dst_trampoline)
2853 		/* we allocated a new trampoline, so free the old one */
2854 		bpf_trampoline_put(prog->aux->dst_trampoline);
2855 
2856 	prog->aux->dst_prog = NULL;
2857 	prog->aux->dst_trampoline = NULL;
2858 	mutex_unlock(&prog->aux->dst_mutex);
2859 
2860 	return bpf_link_settle(&link_primer);
2861 out_unlock:
2862 	if (tr && tr != prog->aux->dst_trampoline)
2863 		bpf_trampoline_put(tr);
2864 	mutex_unlock(&prog->aux->dst_mutex);
2865 	kfree(link);
2866 out_put_prog:
2867 	if (tgt_prog_fd && tgt_prog)
2868 		bpf_prog_put(tgt_prog);
2869 	return err;
2870 }
2871 
2872 struct bpf_raw_tp_link {
2873 	struct bpf_link link;
2874 	struct bpf_raw_event_map *btp;
2875 };
2876 
2877 static void bpf_raw_tp_link_release(struct bpf_link *link)
2878 {
2879 	struct bpf_raw_tp_link *raw_tp =
2880 		container_of(link, struct bpf_raw_tp_link, link);
2881 
2882 	bpf_probe_unregister(raw_tp->btp, raw_tp->link.prog);
2883 	bpf_put_raw_tracepoint(raw_tp->btp);
2884 }
2885 
2886 static void bpf_raw_tp_link_dealloc(struct bpf_link *link)
2887 {
2888 	struct bpf_raw_tp_link *raw_tp =
2889 		container_of(link, struct bpf_raw_tp_link, link);
2890 
2891 	kfree(raw_tp);
2892 }
2893 
2894 static void bpf_raw_tp_link_show_fdinfo(const struct bpf_link *link,
2895 					struct seq_file *seq)
2896 {
2897 	struct bpf_raw_tp_link *raw_tp_link =
2898 		container_of(link, struct bpf_raw_tp_link, link);
2899 
2900 	seq_printf(seq,
2901 		   "tp_name:\t%s\n",
2902 		   raw_tp_link->btp->tp->name);
2903 }
2904 
2905 static int bpf_raw_tp_link_fill_link_info(const struct bpf_link *link,
2906 					  struct bpf_link_info *info)
2907 {
2908 	struct bpf_raw_tp_link *raw_tp_link =
2909 		container_of(link, struct bpf_raw_tp_link, link);
2910 	char __user *ubuf = u64_to_user_ptr(info->raw_tracepoint.tp_name);
2911 	const char *tp_name = raw_tp_link->btp->tp->name;
2912 	u32 ulen = info->raw_tracepoint.tp_name_len;
2913 	size_t tp_len = strlen(tp_name);
2914 
2915 	if (!ulen ^ !ubuf)
2916 		return -EINVAL;
2917 
2918 	info->raw_tracepoint.tp_name_len = tp_len + 1;
2919 
2920 	if (!ubuf)
2921 		return 0;
2922 
2923 	if (ulen >= tp_len + 1) {
2924 		if (copy_to_user(ubuf, tp_name, tp_len + 1))
2925 			return -EFAULT;
2926 	} else {
2927 		char zero = '\0';
2928 
2929 		if (copy_to_user(ubuf, tp_name, ulen - 1))
2930 			return -EFAULT;
2931 		if (put_user(zero, ubuf + ulen - 1))
2932 			return -EFAULT;
2933 		return -ENOSPC;
2934 	}
2935 
2936 	return 0;
2937 }
2938 
2939 static const struct bpf_link_ops bpf_raw_tp_link_lops = {
2940 	.release = bpf_raw_tp_link_release,
2941 	.dealloc = bpf_raw_tp_link_dealloc,
2942 	.show_fdinfo = bpf_raw_tp_link_show_fdinfo,
2943 	.fill_link_info = bpf_raw_tp_link_fill_link_info,
2944 };
2945 
2946 #ifdef CONFIG_PERF_EVENTS
2947 struct bpf_perf_link {
2948 	struct bpf_link link;
2949 	struct file *perf_file;
2950 };
2951 
2952 static void bpf_perf_link_release(struct bpf_link *link)
2953 {
2954 	struct bpf_perf_link *perf_link = container_of(link, struct bpf_perf_link, link);
2955 	struct perf_event *event = perf_link->perf_file->private_data;
2956 
2957 	perf_event_free_bpf_prog(event);
2958 	fput(perf_link->perf_file);
2959 }
2960 
2961 static void bpf_perf_link_dealloc(struct bpf_link *link)
2962 {
2963 	struct bpf_perf_link *perf_link = container_of(link, struct bpf_perf_link, link);
2964 
2965 	kfree(perf_link);
2966 }
2967 
2968 static const struct bpf_link_ops bpf_perf_link_lops = {
2969 	.release = bpf_perf_link_release,
2970 	.dealloc = bpf_perf_link_dealloc,
2971 };
2972 
2973 static int bpf_perf_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
2974 {
2975 	struct bpf_link_primer link_primer;
2976 	struct bpf_perf_link *link;
2977 	struct perf_event *event;
2978 	struct file *perf_file;
2979 	int err;
2980 
2981 	if (attr->link_create.flags)
2982 		return -EINVAL;
2983 
2984 	perf_file = perf_event_get(attr->link_create.target_fd);
2985 	if (IS_ERR(perf_file))
2986 		return PTR_ERR(perf_file);
2987 
2988 	link = kzalloc(sizeof(*link), GFP_USER);
2989 	if (!link) {
2990 		err = -ENOMEM;
2991 		goto out_put_file;
2992 	}
2993 	bpf_link_init(&link->link, BPF_LINK_TYPE_PERF_EVENT, &bpf_perf_link_lops, prog);
2994 	link->perf_file = perf_file;
2995 
2996 	err = bpf_link_prime(&link->link, &link_primer);
2997 	if (err) {
2998 		kfree(link);
2999 		goto out_put_file;
3000 	}
3001 
3002 	event = perf_file->private_data;
3003 	err = perf_event_set_bpf_prog(event, prog, attr->link_create.perf_event.bpf_cookie);
3004 	if (err) {
3005 		bpf_link_cleanup(&link_primer);
3006 		goto out_put_file;
3007 	}
3008 	/* perf_event_set_bpf_prog() doesn't take its own refcnt on prog */
3009 	bpf_prog_inc(prog);
3010 
3011 	return bpf_link_settle(&link_primer);
3012 
3013 out_put_file:
3014 	fput(perf_file);
3015 	return err;
3016 }
3017 #endif /* CONFIG_PERF_EVENTS */
3018 
3019 #define BPF_RAW_TRACEPOINT_OPEN_LAST_FIELD raw_tracepoint.prog_fd
3020 
3021 static int bpf_raw_tracepoint_open(const union bpf_attr *attr)
3022 {
3023 	struct bpf_link_primer link_primer;
3024 	struct bpf_raw_tp_link *link;
3025 	struct bpf_raw_event_map *btp;
3026 	struct bpf_prog *prog;
3027 	const char *tp_name;
3028 	char buf[128];
3029 	int err;
3030 
3031 	if (CHECK_ATTR(BPF_RAW_TRACEPOINT_OPEN))
3032 		return -EINVAL;
3033 
3034 	prog = bpf_prog_get(attr->raw_tracepoint.prog_fd);
3035 	if (IS_ERR(prog))
3036 		return PTR_ERR(prog);
3037 
3038 	switch (prog->type) {
3039 	case BPF_PROG_TYPE_TRACING:
3040 	case BPF_PROG_TYPE_EXT:
3041 	case BPF_PROG_TYPE_LSM:
3042 		if (attr->raw_tracepoint.name) {
3043 			/* The attach point for this category of programs
3044 			 * should be specified via btf_id during program load.
3045 			 */
3046 			err = -EINVAL;
3047 			goto out_put_prog;
3048 		}
3049 		if (prog->type == BPF_PROG_TYPE_TRACING &&
3050 		    prog->expected_attach_type == BPF_TRACE_RAW_TP) {
3051 			tp_name = prog->aux->attach_func_name;
3052 			break;
3053 		}
3054 		err = bpf_tracing_prog_attach(prog, 0, 0);
3055 		if (err >= 0)
3056 			return err;
3057 		goto out_put_prog;
3058 	case BPF_PROG_TYPE_RAW_TRACEPOINT:
3059 	case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE:
3060 		if (strncpy_from_user(buf,
3061 				      u64_to_user_ptr(attr->raw_tracepoint.name),
3062 				      sizeof(buf) - 1) < 0) {
3063 			err = -EFAULT;
3064 			goto out_put_prog;
3065 		}
3066 		buf[sizeof(buf) - 1] = 0;
3067 		tp_name = buf;
3068 		break;
3069 	default:
3070 		err = -EINVAL;
3071 		goto out_put_prog;
3072 	}
3073 
3074 	btp = bpf_get_raw_tracepoint(tp_name);
3075 	if (!btp) {
3076 		err = -ENOENT;
3077 		goto out_put_prog;
3078 	}
3079 
3080 	link = kzalloc(sizeof(*link), GFP_USER);
3081 	if (!link) {
3082 		err = -ENOMEM;
3083 		goto out_put_btp;
3084 	}
3085 	bpf_link_init(&link->link, BPF_LINK_TYPE_RAW_TRACEPOINT,
3086 		      &bpf_raw_tp_link_lops, prog);
3087 	link->btp = btp;
3088 
3089 	err = bpf_link_prime(&link->link, &link_primer);
3090 	if (err) {
3091 		kfree(link);
3092 		goto out_put_btp;
3093 	}
3094 
3095 	err = bpf_probe_register(link->btp, prog);
3096 	if (err) {
3097 		bpf_link_cleanup(&link_primer);
3098 		goto out_put_btp;
3099 	}
3100 
3101 	return bpf_link_settle(&link_primer);
3102 
3103 out_put_btp:
3104 	bpf_put_raw_tracepoint(btp);
3105 out_put_prog:
3106 	bpf_prog_put(prog);
3107 	return err;
3108 }
3109 
3110 static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog,
3111 					     enum bpf_attach_type attach_type)
3112 {
3113 	switch (prog->type) {
3114 	case BPF_PROG_TYPE_CGROUP_SOCK:
3115 	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
3116 	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
3117 	case BPF_PROG_TYPE_SK_LOOKUP:
3118 		return attach_type == prog->expected_attach_type ? 0 : -EINVAL;
3119 	case BPF_PROG_TYPE_CGROUP_SKB:
3120 		if (!capable(CAP_NET_ADMIN))
3121 			/* cg-skb progs can be loaded by unpriv user.
3122 			 * check permissions at attach time.
3123 			 */
3124 			return -EPERM;
3125 		return prog->enforce_expected_attach_type &&
3126 			prog->expected_attach_type != attach_type ?
3127 			-EINVAL : 0;
3128 	default:
3129 		return 0;
3130 	}
3131 }
3132 
3133 static enum bpf_prog_type
3134 attach_type_to_prog_type(enum bpf_attach_type attach_type)
3135 {
3136 	switch (attach_type) {
3137 	case BPF_CGROUP_INET_INGRESS:
3138 	case BPF_CGROUP_INET_EGRESS:
3139 		return BPF_PROG_TYPE_CGROUP_SKB;
3140 	case BPF_CGROUP_INET_SOCK_CREATE:
3141 	case BPF_CGROUP_INET_SOCK_RELEASE:
3142 	case BPF_CGROUP_INET4_POST_BIND:
3143 	case BPF_CGROUP_INET6_POST_BIND:
3144 		return BPF_PROG_TYPE_CGROUP_SOCK;
3145 	case BPF_CGROUP_INET4_BIND:
3146 	case BPF_CGROUP_INET6_BIND:
3147 	case BPF_CGROUP_INET4_CONNECT:
3148 	case BPF_CGROUP_INET6_CONNECT:
3149 	case BPF_CGROUP_INET4_GETPEERNAME:
3150 	case BPF_CGROUP_INET6_GETPEERNAME:
3151 	case BPF_CGROUP_INET4_GETSOCKNAME:
3152 	case BPF_CGROUP_INET6_GETSOCKNAME:
3153 	case BPF_CGROUP_UDP4_SENDMSG:
3154 	case BPF_CGROUP_UDP6_SENDMSG:
3155 	case BPF_CGROUP_UDP4_RECVMSG:
3156 	case BPF_CGROUP_UDP6_RECVMSG:
3157 		return BPF_PROG_TYPE_CGROUP_SOCK_ADDR;
3158 	case BPF_CGROUP_SOCK_OPS:
3159 		return BPF_PROG_TYPE_SOCK_OPS;
3160 	case BPF_CGROUP_DEVICE:
3161 		return BPF_PROG_TYPE_CGROUP_DEVICE;
3162 	case BPF_SK_MSG_VERDICT:
3163 		return BPF_PROG_TYPE_SK_MSG;
3164 	case BPF_SK_SKB_STREAM_PARSER:
3165 	case BPF_SK_SKB_STREAM_VERDICT:
3166 	case BPF_SK_SKB_VERDICT:
3167 		return BPF_PROG_TYPE_SK_SKB;
3168 	case BPF_LIRC_MODE2:
3169 		return BPF_PROG_TYPE_LIRC_MODE2;
3170 	case BPF_FLOW_DISSECTOR:
3171 		return BPF_PROG_TYPE_FLOW_DISSECTOR;
3172 	case BPF_CGROUP_SYSCTL:
3173 		return BPF_PROG_TYPE_CGROUP_SYSCTL;
3174 	case BPF_CGROUP_GETSOCKOPT:
3175 	case BPF_CGROUP_SETSOCKOPT:
3176 		return BPF_PROG_TYPE_CGROUP_SOCKOPT;
3177 	case BPF_TRACE_ITER:
3178 		return BPF_PROG_TYPE_TRACING;
3179 	case BPF_SK_LOOKUP:
3180 		return BPF_PROG_TYPE_SK_LOOKUP;
3181 	case BPF_XDP:
3182 		return BPF_PROG_TYPE_XDP;
3183 	default:
3184 		return BPF_PROG_TYPE_UNSPEC;
3185 	}
3186 }
3187 
3188 #define BPF_PROG_ATTACH_LAST_FIELD replace_bpf_fd
3189 
3190 #define BPF_F_ATTACH_MASK \
3191 	(BPF_F_ALLOW_OVERRIDE | BPF_F_ALLOW_MULTI | BPF_F_REPLACE)
3192 
3193 static int bpf_prog_attach(const union bpf_attr *attr)
3194 {
3195 	enum bpf_prog_type ptype;
3196 	struct bpf_prog *prog;
3197 	int ret;
3198 
3199 	if (CHECK_ATTR(BPF_PROG_ATTACH))
3200 		return -EINVAL;
3201 
3202 	if (attr->attach_flags & ~BPF_F_ATTACH_MASK)
3203 		return -EINVAL;
3204 
3205 	ptype = attach_type_to_prog_type(attr->attach_type);
3206 	if (ptype == BPF_PROG_TYPE_UNSPEC)
3207 		return -EINVAL;
3208 
3209 	prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype);
3210 	if (IS_ERR(prog))
3211 		return PTR_ERR(prog);
3212 
3213 	if (bpf_prog_attach_check_attach_type(prog, attr->attach_type)) {
3214 		bpf_prog_put(prog);
3215 		return -EINVAL;
3216 	}
3217 
3218 	switch (ptype) {
3219 	case BPF_PROG_TYPE_SK_SKB:
3220 	case BPF_PROG_TYPE_SK_MSG:
3221 		ret = sock_map_get_from_fd(attr, prog);
3222 		break;
3223 	case BPF_PROG_TYPE_LIRC_MODE2:
3224 		ret = lirc_prog_attach(attr, prog);
3225 		break;
3226 	case BPF_PROG_TYPE_FLOW_DISSECTOR:
3227 		ret = netns_bpf_prog_attach(attr, prog);
3228 		break;
3229 	case BPF_PROG_TYPE_CGROUP_DEVICE:
3230 	case BPF_PROG_TYPE_CGROUP_SKB:
3231 	case BPF_PROG_TYPE_CGROUP_SOCK:
3232 	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
3233 	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
3234 	case BPF_PROG_TYPE_CGROUP_SYSCTL:
3235 	case BPF_PROG_TYPE_SOCK_OPS:
3236 		ret = cgroup_bpf_prog_attach(attr, ptype, prog);
3237 		break;
3238 	default:
3239 		ret = -EINVAL;
3240 	}
3241 
3242 	if (ret)
3243 		bpf_prog_put(prog);
3244 	return ret;
3245 }
3246 
3247 #define BPF_PROG_DETACH_LAST_FIELD attach_type
3248 
3249 static int bpf_prog_detach(const union bpf_attr *attr)
3250 {
3251 	enum bpf_prog_type ptype;
3252 
3253 	if (CHECK_ATTR(BPF_PROG_DETACH))
3254 		return -EINVAL;
3255 
3256 	ptype = attach_type_to_prog_type(attr->attach_type);
3257 
3258 	switch (ptype) {
3259 	case BPF_PROG_TYPE_SK_MSG:
3260 	case BPF_PROG_TYPE_SK_SKB:
3261 		return sock_map_prog_detach(attr, ptype);
3262 	case BPF_PROG_TYPE_LIRC_MODE2:
3263 		return lirc_prog_detach(attr);
3264 	case BPF_PROG_TYPE_FLOW_DISSECTOR:
3265 		return netns_bpf_prog_detach(attr, ptype);
3266 	case BPF_PROG_TYPE_CGROUP_DEVICE:
3267 	case BPF_PROG_TYPE_CGROUP_SKB:
3268 	case BPF_PROG_TYPE_CGROUP_SOCK:
3269 	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
3270 	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
3271 	case BPF_PROG_TYPE_CGROUP_SYSCTL:
3272 	case BPF_PROG_TYPE_SOCK_OPS:
3273 		return cgroup_bpf_prog_detach(attr, ptype);
3274 	default:
3275 		return -EINVAL;
3276 	}
3277 }
3278 
3279 #define BPF_PROG_QUERY_LAST_FIELD query.prog_cnt
3280 
3281 static int bpf_prog_query(const union bpf_attr *attr,
3282 			  union bpf_attr __user *uattr)
3283 {
3284 	if (!capable(CAP_NET_ADMIN))
3285 		return -EPERM;
3286 	if (CHECK_ATTR(BPF_PROG_QUERY))
3287 		return -EINVAL;
3288 	if (attr->query.query_flags & ~BPF_F_QUERY_EFFECTIVE)
3289 		return -EINVAL;
3290 
3291 	switch (attr->query.attach_type) {
3292 	case BPF_CGROUP_INET_INGRESS:
3293 	case BPF_CGROUP_INET_EGRESS:
3294 	case BPF_CGROUP_INET_SOCK_CREATE:
3295 	case BPF_CGROUP_INET_SOCK_RELEASE:
3296 	case BPF_CGROUP_INET4_BIND:
3297 	case BPF_CGROUP_INET6_BIND:
3298 	case BPF_CGROUP_INET4_POST_BIND:
3299 	case BPF_CGROUP_INET6_POST_BIND:
3300 	case BPF_CGROUP_INET4_CONNECT:
3301 	case BPF_CGROUP_INET6_CONNECT:
3302 	case BPF_CGROUP_INET4_GETPEERNAME:
3303 	case BPF_CGROUP_INET6_GETPEERNAME:
3304 	case BPF_CGROUP_INET4_GETSOCKNAME:
3305 	case BPF_CGROUP_INET6_GETSOCKNAME:
3306 	case BPF_CGROUP_UDP4_SENDMSG:
3307 	case BPF_CGROUP_UDP6_SENDMSG:
3308 	case BPF_CGROUP_UDP4_RECVMSG:
3309 	case BPF_CGROUP_UDP6_RECVMSG:
3310 	case BPF_CGROUP_SOCK_OPS:
3311 	case BPF_CGROUP_DEVICE:
3312 	case BPF_CGROUP_SYSCTL:
3313 	case BPF_CGROUP_GETSOCKOPT:
3314 	case BPF_CGROUP_SETSOCKOPT:
3315 		return cgroup_bpf_prog_query(attr, uattr);
3316 	case BPF_LIRC_MODE2:
3317 		return lirc_prog_query(attr, uattr);
3318 	case BPF_FLOW_DISSECTOR:
3319 	case BPF_SK_LOOKUP:
3320 		return netns_bpf_prog_query(attr, uattr);
3321 	default:
3322 		return -EINVAL;
3323 	}
3324 }
3325 
3326 #define BPF_PROG_TEST_RUN_LAST_FIELD test.cpu
3327 
3328 static int bpf_prog_test_run(const union bpf_attr *attr,
3329 			     union bpf_attr __user *uattr)
3330 {
3331 	struct bpf_prog *prog;
3332 	int ret = -ENOTSUPP;
3333 
3334 	if (CHECK_ATTR(BPF_PROG_TEST_RUN))
3335 		return -EINVAL;
3336 
3337 	if ((attr->test.ctx_size_in && !attr->test.ctx_in) ||
3338 	    (!attr->test.ctx_size_in && attr->test.ctx_in))
3339 		return -EINVAL;
3340 
3341 	if ((attr->test.ctx_size_out && !attr->test.ctx_out) ||
3342 	    (!attr->test.ctx_size_out && attr->test.ctx_out))
3343 		return -EINVAL;
3344 
3345 	prog = bpf_prog_get(attr->test.prog_fd);
3346 	if (IS_ERR(prog))
3347 		return PTR_ERR(prog);
3348 
3349 	if (prog->aux->ops->test_run)
3350 		ret = prog->aux->ops->test_run(prog, attr, uattr);
3351 
3352 	bpf_prog_put(prog);
3353 	return ret;
3354 }
3355 
3356 #define BPF_OBJ_GET_NEXT_ID_LAST_FIELD next_id
3357 
3358 static int bpf_obj_get_next_id(const union bpf_attr *attr,
3359 			       union bpf_attr __user *uattr,
3360 			       struct idr *idr,
3361 			       spinlock_t *lock)
3362 {
3363 	u32 next_id = attr->start_id;
3364 	int err = 0;
3365 
3366 	if (CHECK_ATTR(BPF_OBJ_GET_NEXT_ID) || next_id >= INT_MAX)
3367 		return -EINVAL;
3368 
3369 	if (!capable(CAP_SYS_ADMIN))
3370 		return -EPERM;
3371 
3372 	next_id++;
3373 	spin_lock_bh(lock);
3374 	if (!idr_get_next(idr, &next_id))
3375 		err = -ENOENT;
3376 	spin_unlock_bh(lock);
3377 
3378 	if (!err)
3379 		err = put_user(next_id, &uattr->next_id);
3380 
3381 	return err;
3382 }
3383 
3384 struct bpf_map *bpf_map_get_curr_or_next(u32 *id)
3385 {
3386 	struct bpf_map *map;
3387 
3388 	spin_lock_bh(&map_idr_lock);
3389 again:
3390 	map = idr_get_next(&map_idr, id);
3391 	if (map) {
3392 		map = __bpf_map_inc_not_zero(map, false);
3393 		if (IS_ERR(map)) {
3394 			(*id)++;
3395 			goto again;
3396 		}
3397 	}
3398 	spin_unlock_bh(&map_idr_lock);
3399 
3400 	return map;
3401 }
3402 
3403 struct bpf_prog *bpf_prog_get_curr_or_next(u32 *id)
3404 {
3405 	struct bpf_prog *prog;
3406 
3407 	spin_lock_bh(&prog_idr_lock);
3408 again:
3409 	prog = idr_get_next(&prog_idr, id);
3410 	if (prog) {
3411 		prog = bpf_prog_inc_not_zero(prog);
3412 		if (IS_ERR(prog)) {
3413 			(*id)++;
3414 			goto again;
3415 		}
3416 	}
3417 	spin_unlock_bh(&prog_idr_lock);
3418 
3419 	return prog;
3420 }
3421 
3422 #define BPF_PROG_GET_FD_BY_ID_LAST_FIELD prog_id
3423 
3424 struct bpf_prog *bpf_prog_by_id(u32 id)
3425 {
3426 	struct bpf_prog *prog;
3427 
3428 	if (!id)
3429 		return ERR_PTR(-ENOENT);
3430 
3431 	spin_lock_bh(&prog_idr_lock);
3432 	prog = idr_find(&prog_idr, id);
3433 	if (prog)
3434 		prog = bpf_prog_inc_not_zero(prog);
3435 	else
3436 		prog = ERR_PTR(-ENOENT);
3437 	spin_unlock_bh(&prog_idr_lock);
3438 	return prog;
3439 }
3440 
3441 static int bpf_prog_get_fd_by_id(const union bpf_attr *attr)
3442 {
3443 	struct bpf_prog *prog;
3444 	u32 id = attr->prog_id;
3445 	int fd;
3446 
3447 	if (CHECK_ATTR(BPF_PROG_GET_FD_BY_ID))
3448 		return -EINVAL;
3449 
3450 	if (!capable(CAP_SYS_ADMIN))
3451 		return -EPERM;
3452 
3453 	prog = bpf_prog_by_id(id);
3454 	if (IS_ERR(prog))
3455 		return PTR_ERR(prog);
3456 
3457 	fd = bpf_prog_new_fd(prog);
3458 	if (fd < 0)
3459 		bpf_prog_put(prog);
3460 
3461 	return fd;
3462 }
3463 
3464 #define BPF_MAP_GET_FD_BY_ID_LAST_FIELD open_flags
3465 
3466 static int bpf_map_get_fd_by_id(const union bpf_attr *attr)
3467 {
3468 	struct bpf_map *map;
3469 	u32 id = attr->map_id;
3470 	int f_flags;
3471 	int fd;
3472 
3473 	if (CHECK_ATTR(BPF_MAP_GET_FD_BY_ID) ||
3474 	    attr->open_flags & ~BPF_OBJ_FLAG_MASK)
3475 		return -EINVAL;
3476 
3477 	if (!capable(CAP_SYS_ADMIN))
3478 		return -EPERM;
3479 
3480 	f_flags = bpf_get_file_flag(attr->open_flags);
3481 	if (f_flags < 0)
3482 		return f_flags;
3483 
3484 	spin_lock_bh(&map_idr_lock);
3485 	map = idr_find(&map_idr, id);
3486 	if (map)
3487 		map = __bpf_map_inc_not_zero(map, true);
3488 	else
3489 		map = ERR_PTR(-ENOENT);
3490 	spin_unlock_bh(&map_idr_lock);
3491 
3492 	if (IS_ERR(map))
3493 		return PTR_ERR(map);
3494 
3495 	fd = bpf_map_new_fd(map, f_flags);
3496 	if (fd < 0)
3497 		bpf_map_put_with_uref(map);
3498 
3499 	return fd;
3500 }
3501 
3502 static const struct bpf_map *bpf_map_from_imm(const struct bpf_prog *prog,
3503 					      unsigned long addr, u32 *off,
3504 					      u32 *type)
3505 {
3506 	const struct bpf_map *map;
3507 	int i;
3508 
3509 	mutex_lock(&prog->aux->used_maps_mutex);
3510 	for (i = 0, *off = 0; i < prog->aux->used_map_cnt; i++) {
3511 		map = prog->aux->used_maps[i];
3512 		if (map == (void *)addr) {
3513 			*type = BPF_PSEUDO_MAP_FD;
3514 			goto out;
3515 		}
3516 		if (!map->ops->map_direct_value_meta)
3517 			continue;
3518 		if (!map->ops->map_direct_value_meta(map, addr, off)) {
3519 			*type = BPF_PSEUDO_MAP_VALUE;
3520 			goto out;
3521 		}
3522 	}
3523 	map = NULL;
3524 
3525 out:
3526 	mutex_unlock(&prog->aux->used_maps_mutex);
3527 	return map;
3528 }
3529 
3530 static struct bpf_insn *bpf_insn_prepare_dump(const struct bpf_prog *prog,
3531 					      const struct cred *f_cred)
3532 {
3533 	const struct bpf_map *map;
3534 	struct bpf_insn *insns;
3535 	u32 off, type;
3536 	u64 imm;
3537 	u8 code;
3538 	int i;
3539 
3540 	insns = kmemdup(prog->insnsi, bpf_prog_insn_size(prog),
3541 			GFP_USER);
3542 	if (!insns)
3543 		return insns;
3544 
3545 	for (i = 0; i < prog->len; i++) {
3546 		code = insns[i].code;
3547 
3548 		if (code == (BPF_JMP | BPF_TAIL_CALL)) {
3549 			insns[i].code = BPF_JMP | BPF_CALL;
3550 			insns[i].imm = BPF_FUNC_tail_call;
3551 			/* fall-through */
3552 		}
3553 		if (code == (BPF_JMP | BPF_CALL) ||
3554 		    code == (BPF_JMP | BPF_CALL_ARGS)) {
3555 			if (code == (BPF_JMP | BPF_CALL_ARGS))
3556 				insns[i].code = BPF_JMP | BPF_CALL;
3557 			if (!bpf_dump_raw_ok(f_cred))
3558 				insns[i].imm = 0;
3559 			continue;
3560 		}
3561 		if (BPF_CLASS(code) == BPF_LDX && BPF_MODE(code) == BPF_PROBE_MEM) {
3562 			insns[i].code = BPF_LDX | BPF_SIZE(code) | BPF_MEM;
3563 			continue;
3564 		}
3565 
3566 		if (code != (BPF_LD | BPF_IMM | BPF_DW))
3567 			continue;
3568 
3569 		imm = ((u64)insns[i + 1].imm << 32) | (u32)insns[i].imm;
3570 		map = bpf_map_from_imm(prog, imm, &off, &type);
3571 		if (map) {
3572 			insns[i].src_reg = type;
3573 			insns[i].imm = map->id;
3574 			insns[i + 1].imm = off;
3575 			continue;
3576 		}
3577 	}
3578 
3579 	return insns;
3580 }
3581 
3582 static int set_info_rec_size(struct bpf_prog_info *info)
3583 {
3584 	/*
3585 	 * Ensure info.*_rec_size is the same as kernel expected size
3586 	 *
3587 	 * or
3588 	 *
3589 	 * Only allow zero *_rec_size if both _rec_size and _cnt are
3590 	 * zero.  In this case, the kernel will set the expected
3591 	 * _rec_size back to the info.
3592 	 */
3593 
3594 	if ((info->nr_func_info || info->func_info_rec_size) &&
3595 	    info->func_info_rec_size != sizeof(struct bpf_func_info))
3596 		return -EINVAL;
3597 
3598 	if ((info->nr_line_info || info->line_info_rec_size) &&
3599 	    info->line_info_rec_size != sizeof(struct bpf_line_info))
3600 		return -EINVAL;
3601 
3602 	if ((info->nr_jited_line_info || info->jited_line_info_rec_size) &&
3603 	    info->jited_line_info_rec_size != sizeof(__u64))
3604 		return -EINVAL;
3605 
3606 	info->func_info_rec_size = sizeof(struct bpf_func_info);
3607 	info->line_info_rec_size = sizeof(struct bpf_line_info);
3608 	info->jited_line_info_rec_size = sizeof(__u64);
3609 
3610 	return 0;
3611 }
3612 
3613 static int bpf_prog_get_info_by_fd(struct file *file,
3614 				   struct bpf_prog *prog,
3615 				   const union bpf_attr *attr,
3616 				   union bpf_attr __user *uattr)
3617 {
3618 	struct bpf_prog_info __user *uinfo = u64_to_user_ptr(attr->info.info);
3619 	struct bpf_prog_info info;
3620 	u32 info_len = attr->info.info_len;
3621 	struct bpf_prog_kstats stats;
3622 	char __user *uinsns;
3623 	u32 ulen;
3624 	int err;
3625 
3626 	err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len);
3627 	if (err)
3628 		return err;
3629 	info_len = min_t(u32, sizeof(info), info_len);
3630 
3631 	memset(&info, 0, sizeof(info));
3632 	if (copy_from_user(&info, uinfo, info_len))
3633 		return -EFAULT;
3634 
3635 	info.type = prog->type;
3636 	info.id = prog->aux->id;
3637 	info.load_time = prog->aux->load_time;
3638 	info.created_by_uid = from_kuid_munged(current_user_ns(),
3639 					       prog->aux->user->uid);
3640 	info.gpl_compatible = prog->gpl_compatible;
3641 
3642 	memcpy(info.tag, prog->tag, sizeof(prog->tag));
3643 	memcpy(info.name, prog->aux->name, sizeof(prog->aux->name));
3644 
3645 	mutex_lock(&prog->aux->used_maps_mutex);
3646 	ulen = info.nr_map_ids;
3647 	info.nr_map_ids = prog->aux->used_map_cnt;
3648 	ulen = min_t(u32, info.nr_map_ids, ulen);
3649 	if (ulen) {
3650 		u32 __user *user_map_ids = u64_to_user_ptr(info.map_ids);
3651 		u32 i;
3652 
3653 		for (i = 0; i < ulen; i++)
3654 			if (put_user(prog->aux->used_maps[i]->id,
3655 				     &user_map_ids[i])) {
3656 				mutex_unlock(&prog->aux->used_maps_mutex);
3657 				return -EFAULT;
3658 			}
3659 	}
3660 	mutex_unlock(&prog->aux->used_maps_mutex);
3661 
3662 	err = set_info_rec_size(&info);
3663 	if (err)
3664 		return err;
3665 
3666 	bpf_prog_get_stats(prog, &stats);
3667 	info.run_time_ns = stats.nsecs;
3668 	info.run_cnt = stats.cnt;
3669 	info.recursion_misses = stats.misses;
3670 
3671 	info.verified_insns = prog->aux->verified_insns;
3672 
3673 	if (!bpf_capable()) {
3674 		info.jited_prog_len = 0;
3675 		info.xlated_prog_len = 0;
3676 		info.nr_jited_ksyms = 0;
3677 		info.nr_jited_func_lens = 0;
3678 		info.nr_func_info = 0;
3679 		info.nr_line_info = 0;
3680 		info.nr_jited_line_info = 0;
3681 		goto done;
3682 	}
3683 
3684 	ulen = info.xlated_prog_len;
3685 	info.xlated_prog_len = bpf_prog_insn_size(prog);
3686 	if (info.xlated_prog_len && ulen) {
3687 		struct bpf_insn *insns_sanitized;
3688 		bool fault;
3689 
3690 		if (prog->blinded && !bpf_dump_raw_ok(file->f_cred)) {
3691 			info.xlated_prog_insns = 0;
3692 			goto done;
3693 		}
3694 		insns_sanitized = bpf_insn_prepare_dump(prog, file->f_cred);
3695 		if (!insns_sanitized)
3696 			return -ENOMEM;
3697 		uinsns = u64_to_user_ptr(info.xlated_prog_insns);
3698 		ulen = min_t(u32, info.xlated_prog_len, ulen);
3699 		fault = copy_to_user(uinsns, insns_sanitized, ulen);
3700 		kfree(insns_sanitized);
3701 		if (fault)
3702 			return -EFAULT;
3703 	}
3704 
3705 	if (bpf_prog_is_dev_bound(prog->aux)) {
3706 		err = bpf_prog_offload_info_fill(&info, prog);
3707 		if (err)
3708 			return err;
3709 		goto done;
3710 	}
3711 
3712 	/* NOTE: the following code is supposed to be skipped for offload.
3713 	 * bpf_prog_offload_info_fill() is the place to fill similar fields
3714 	 * for offload.
3715 	 */
3716 	ulen = info.jited_prog_len;
3717 	if (prog->aux->func_cnt) {
3718 		u32 i;
3719 
3720 		info.jited_prog_len = 0;
3721 		for (i = 0; i < prog->aux->func_cnt; i++)
3722 			info.jited_prog_len += prog->aux->func[i]->jited_len;
3723 	} else {
3724 		info.jited_prog_len = prog->jited_len;
3725 	}
3726 
3727 	if (info.jited_prog_len && ulen) {
3728 		if (bpf_dump_raw_ok(file->f_cred)) {
3729 			uinsns = u64_to_user_ptr(info.jited_prog_insns);
3730 			ulen = min_t(u32, info.jited_prog_len, ulen);
3731 
3732 			/* for multi-function programs, copy the JITed
3733 			 * instructions for all the functions
3734 			 */
3735 			if (prog->aux->func_cnt) {
3736 				u32 len, free, i;
3737 				u8 *img;
3738 
3739 				free = ulen;
3740 				for (i = 0; i < prog->aux->func_cnt; i++) {
3741 					len = prog->aux->func[i]->jited_len;
3742 					len = min_t(u32, len, free);
3743 					img = (u8 *) prog->aux->func[i]->bpf_func;
3744 					if (copy_to_user(uinsns, img, len))
3745 						return -EFAULT;
3746 					uinsns += len;
3747 					free -= len;
3748 					if (!free)
3749 						break;
3750 				}
3751 			} else {
3752 				if (copy_to_user(uinsns, prog->bpf_func, ulen))
3753 					return -EFAULT;
3754 			}
3755 		} else {
3756 			info.jited_prog_insns = 0;
3757 		}
3758 	}
3759 
3760 	ulen = info.nr_jited_ksyms;
3761 	info.nr_jited_ksyms = prog->aux->func_cnt ? : 1;
3762 	if (ulen) {
3763 		if (bpf_dump_raw_ok(file->f_cred)) {
3764 			unsigned long ksym_addr;
3765 			u64 __user *user_ksyms;
3766 			u32 i;
3767 
3768 			/* copy the address of the kernel symbol
3769 			 * corresponding to each function
3770 			 */
3771 			ulen = min_t(u32, info.nr_jited_ksyms, ulen);
3772 			user_ksyms = u64_to_user_ptr(info.jited_ksyms);
3773 			if (prog->aux->func_cnt) {
3774 				for (i = 0; i < ulen; i++) {
3775 					ksym_addr = (unsigned long)
3776 						prog->aux->func[i]->bpf_func;
3777 					if (put_user((u64) ksym_addr,
3778 						     &user_ksyms[i]))
3779 						return -EFAULT;
3780 				}
3781 			} else {
3782 				ksym_addr = (unsigned long) prog->bpf_func;
3783 				if (put_user((u64) ksym_addr, &user_ksyms[0]))
3784 					return -EFAULT;
3785 			}
3786 		} else {
3787 			info.jited_ksyms = 0;
3788 		}
3789 	}
3790 
3791 	ulen = info.nr_jited_func_lens;
3792 	info.nr_jited_func_lens = prog->aux->func_cnt ? : 1;
3793 	if (ulen) {
3794 		if (bpf_dump_raw_ok(file->f_cred)) {
3795 			u32 __user *user_lens;
3796 			u32 func_len, i;
3797 
3798 			/* copy the JITed image lengths for each function */
3799 			ulen = min_t(u32, info.nr_jited_func_lens, ulen);
3800 			user_lens = u64_to_user_ptr(info.jited_func_lens);
3801 			if (prog->aux->func_cnt) {
3802 				for (i = 0; i < ulen; i++) {
3803 					func_len =
3804 						prog->aux->func[i]->jited_len;
3805 					if (put_user(func_len, &user_lens[i]))
3806 						return -EFAULT;
3807 				}
3808 			} else {
3809 				func_len = prog->jited_len;
3810 				if (put_user(func_len, &user_lens[0]))
3811 					return -EFAULT;
3812 			}
3813 		} else {
3814 			info.jited_func_lens = 0;
3815 		}
3816 	}
3817 
3818 	if (prog->aux->btf)
3819 		info.btf_id = btf_obj_id(prog->aux->btf);
3820 
3821 	ulen = info.nr_func_info;
3822 	info.nr_func_info = prog->aux->func_info_cnt;
3823 	if (info.nr_func_info && ulen) {
3824 		char __user *user_finfo;
3825 
3826 		user_finfo = u64_to_user_ptr(info.func_info);
3827 		ulen = min_t(u32, info.nr_func_info, ulen);
3828 		if (copy_to_user(user_finfo, prog->aux->func_info,
3829 				 info.func_info_rec_size * ulen))
3830 			return -EFAULT;
3831 	}
3832 
3833 	ulen = info.nr_line_info;
3834 	info.nr_line_info = prog->aux->nr_linfo;
3835 	if (info.nr_line_info && ulen) {
3836 		__u8 __user *user_linfo;
3837 
3838 		user_linfo = u64_to_user_ptr(info.line_info);
3839 		ulen = min_t(u32, info.nr_line_info, ulen);
3840 		if (copy_to_user(user_linfo, prog->aux->linfo,
3841 				 info.line_info_rec_size * ulen))
3842 			return -EFAULT;
3843 	}
3844 
3845 	ulen = info.nr_jited_line_info;
3846 	if (prog->aux->jited_linfo)
3847 		info.nr_jited_line_info = prog->aux->nr_linfo;
3848 	else
3849 		info.nr_jited_line_info = 0;
3850 	if (info.nr_jited_line_info && ulen) {
3851 		if (bpf_dump_raw_ok(file->f_cred)) {
3852 			__u64 __user *user_linfo;
3853 			u32 i;
3854 
3855 			user_linfo = u64_to_user_ptr(info.jited_line_info);
3856 			ulen = min_t(u32, info.nr_jited_line_info, ulen);
3857 			for (i = 0; i < ulen; i++) {
3858 				if (put_user((__u64)(long)prog->aux->jited_linfo[i],
3859 					     &user_linfo[i]))
3860 					return -EFAULT;
3861 			}
3862 		} else {
3863 			info.jited_line_info = 0;
3864 		}
3865 	}
3866 
3867 	ulen = info.nr_prog_tags;
3868 	info.nr_prog_tags = prog->aux->func_cnt ? : 1;
3869 	if (ulen) {
3870 		__u8 __user (*user_prog_tags)[BPF_TAG_SIZE];
3871 		u32 i;
3872 
3873 		user_prog_tags = u64_to_user_ptr(info.prog_tags);
3874 		ulen = min_t(u32, info.nr_prog_tags, ulen);
3875 		if (prog->aux->func_cnt) {
3876 			for (i = 0; i < ulen; i++) {
3877 				if (copy_to_user(user_prog_tags[i],
3878 						 prog->aux->func[i]->tag,
3879 						 BPF_TAG_SIZE))
3880 					return -EFAULT;
3881 			}
3882 		} else {
3883 			if (copy_to_user(user_prog_tags[0],
3884 					 prog->tag, BPF_TAG_SIZE))
3885 				return -EFAULT;
3886 		}
3887 	}
3888 
3889 done:
3890 	if (copy_to_user(uinfo, &info, info_len) ||
3891 	    put_user(info_len, &uattr->info.info_len))
3892 		return -EFAULT;
3893 
3894 	return 0;
3895 }
3896 
3897 static int bpf_map_get_info_by_fd(struct file *file,
3898 				  struct bpf_map *map,
3899 				  const union bpf_attr *attr,
3900 				  union bpf_attr __user *uattr)
3901 {
3902 	struct bpf_map_info __user *uinfo = u64_to_user_ptr(attr->info.info);
3903 	struct bpf_map_info info;
3904 	u32 info_len = attr->info.info_len;
3905 	int err;
3906 
3907 	err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len);
3908 	if (err)
3909 		return err;
3910 	info_len = min_t(u32, sizeof(info), info_len);
3911 
3912 	memset(&info, 0, sizeof(info));
3913 	info.type = map->map_type;
3914 	info.id = map->id;
3915 	info.key_size = map->key_size;
3916 	info.value_size = map->value_size;
3917 	info.max_entries = map->max_entries;
3918 	info.map_flags = map->map_flags;
3919 	info.map_extra = map->map_extra;
3920 	memcpy(info.name, map->name, sizeof(map->name));
3921 
3922 	if (map->btf) {
3923 		info.btf_id = btf_obj_id(map->btf);
3924 		info.btf_key_type_id = map->btf_key_type_id;
3925 		info.btf_value_type_id = map->btf_value_type_id;
3926 	}
3927 	info.btf_vmlinux_value_type_id = map->btf_vmlinux_value_type_id;
3928 
3929 	if (bpf_map_is_dev_bound(map)) {
3930 		err = bpf_map_offload_info_fill(&info, map);
3931 		if (err)
3932 			return err;
3933 	}
3934 
3935 	if (copy_to_user(uinfo, &info, info_len) ||
3936 	    put_user(info_len, &uattr->info.info_len))
3937 		return -EFAULT;
3938 
3939 	return 0;
3940 }
3941 
3942 static int bpf_btf_get_info_by_fd(struct file *file,
3943 				  struct btf *btf,
3944 				  const union bpf_attr *attr,
3945 				  union bpf_attr __user *uattr)
3946 {
3947 	struct bpf_btf_info __user *uinfo = u64_to_user_ptr(attr->info.info);
3948 	u32 info_len = attr->info.info_len;
3949 	int err;
3950 
3951 	err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(*uinfo), info_len);
3952 	if (err)
3953 		return err;
3954 
3955 	return btf_get_info_by_fd(btf, attr, uattr);
3956 }
3957 
3958 static int bpf_link_get_info_by_fd(struct file *file,
3959 				  struct bpf_link *link,
3960 				  const union bpf_attr *attr,
3961 				  union bpf_attr __user *uattr)
3962 {
3963 	struct bpf_link_info __user *uinfo = u64_to_user_ptr(attr->info.info);
3964 	struct bpf_link_info info;
3965 	u32 info_len = attr->info.info_len;
3966 	int err;
3967 
3968 	err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len);
3969 	if (err)
3970 		return err;
3971 	info_len = min_t(u32, sizeof(info), info_len);
3972 
3973 	memset(&info, 0, sizeof(info));
3974 	if (copy_from_user(&info, uinfo, info_len))
3975 		return -EFAULT;
3976 
3977 	info.type = link->type;
3978 	info.id = link->id;
3979 	info.prog_id = link->prog->aux->id;
3980 
3981 	if (link->ops->fill_link_info) {
3982 		err = link->ops->fill_link_info(link, &info);
3983 		if (err)
3984 			return err;
3985 	}
3986 
3987 	if (copy_to_user(uinfo, &info, info_len) ||
3988 	    put_user(info_len, &uattr->info.info_len))
3989 		return -EFAULT;
3990 
3991 	return 0;
3992 }
3993 
3994 
3995 #define BPF_OBJ_GET_INFO_BY_FD_LAST_FIELD info.info
3996 
3997 static int bpf_obj_get_info_by_fd(const union bpf_attr *attr,
3998 				  union bpf_attr __user *uattr)
3999 {
4000 	int ufd = attr->info.bpf_fd;
4001 	struct fd f;
4002 	int err;
4003 
4004 	if (CHECK_ATTR(BPF_OBJ_GET_INFO_BY_FD))
4005 		return -EINVAL;
4006 
4007 	f = fdget(ufd);
4008 	if (!f.file)
4009 		return -EBADFD;
4010 
4011 	if (f.file->f_op == &bpf_prog_fops)
4012 		err = bpf_prog_get_info_by_fd(f.file, f.file->private_data, attr,
4013 					      uattr);
4014 	else if (f.file->f_op == &bpf_map_fops)
4015 		err = bpf_map_get_info_by_fd(f.file, f.file->private_data, attr,
4016 					     uattr);
4017 	else if (f.file->f_op == &btf_fops)
4018 		err = bpf_btf_get_info_by_fd(f.file, f.file->private_data, attr, uattr);
4019 	else if (f.file->f_op == &bpf_link_fops)
4020 		err = bpf_link_get_info_by_fd(f.file, f.file->private_data,
4021 					      attr, uattr);
4022 	else
4023 		err = -EINVAL;
4024 
4025 	fdput(f);
4026 	return err;
4027 }
4028 
4029 #define BPF_BTF_LOAD_LAST_FIELD btf_log_level
4030 
4031 static int bpf_btf_load(const union bpf_attr *attr, bpfptr_t uattr)
4032 {
4033 	if (CHECK_ATTR(BPF_BTF_LOAD))
4034 		return -EINVAL;
4035 
4036 	if (!bpf_capable())
4037 		return -EPERM;
4038 
4039 	return btf_new_fd(attr, uattr);
4040 }
4041 
4042 #define BPF_BTF_GET_FD_BY_ID_LAST_FIELD btf_id
4043 
4044 static int bpf_btf_get_fd_by_id(const union bpf_attr *attr)
4045 {
4046 	if (CHECK_ATTR(BPF_BTF_GET_FD_BY_ID))
4047 		return -EINVAL;
4048 
4049 	if (!capable(CAP_SYS_ADMIN))
4050 		return -EPERM;
4051 
4052 	return btf_get_fd_by_id(attr->btf_id);
4053 }
4054 
4055 static int bpf_task_fd_query_copy(const union bpf_attr *attr,
4056 				    union bpf_attr __user *uattr,
4057 				    u32 prog_id, u32 fd_type,
4058 				    const char *buf, u64 probe_offset,
4059 				    u64 probe_addr)
4060 {
4061 	char __user *ubuf = u64_to_user_ptr(attr->task_fd_query.buf);
4062 	u32 len = buf ? strlen(buf) : 0, input_len;
4063 	int err = 0;
4064 
4065 	if (put_user(len, &uattr->task_fd_query.buf_len))
4066 		return -EFAULT;
4067 	input_len = attr->task_fd_query.buf_len;
4068 	if (input_len && ubuf) {
4069 		if (!len) {
4070 			/* nothing to copy, just make ubuf NULL terminated */
4071 			char zero = '\0';
4072 
4073 			if (put_user(zero, ubuf))
4074 				return -EFAULT;
4075 		} else if (input_len >= len + 1) {
4076 			/* ubuf can hold the string with NULL terminator */
4077 			if (copy_to_user(ubuf, buf, len + 1))
4078 				return -EFAULT;
4079 		} else {
4080 			/* ubuf cannot hold the string with NULL terminator,
4081 			 * do a partial copy with NULL terminator.
4082 			 */
4083 			char zero = '\0';
4084 
4085 			err = -ENOSPC;
4086 			if (copy_to_user(ubuf, buf, input_len - 1))
4087 				return -EFAULT;
4088 			if (put_user(zero, ubuf + input_len - 1))
4089 				return -EFAULT;
4090 		}
4091 	}
4092 
4093 	if (put_user(prog_id, &uattr->task_fd_query.prog_id) ||
4094 	    put_user(fd_type, &uattr->task_fd_query.fd_type) ||
4095 	    put_user(probe_offset, &uattr->task_fd_query.probe_offset) ||
4096 	    put_user(probe_addr, &uattr->task_fd_query.probe_addr))
4097 		return -EFAULT;
4098 
4099 	return err;
4100 }
4101 
4102 #define BPF_TASK_FD_QUERY_LAST_FIELD task_fd_query.probe_addr
4103 
4104 static int bpf_task_fd_query(const union bpf_attr *attr,
4105 			     union bpf_attr __user *uattr)
4106 {
4107 	pid_t pid = attr->task_fd_query.pid;
4108 	u32 fd = attr->task_fd_query.fd;
4109 	const struct perf_event *event;
4110 	struct task_struct *task;
4111 	struct file *file;
4112 	int err;
4113 
4114 	if (CHECK_ATTR(BPF_TASK_FD_QUERY))
4115 		return -EINVAL;
4116 
4117 	if (!capable(CAP_SYS_ADMIN))
4118 		return -EPERM;
4119 
4120 	if (attr->task_fd_query.flags != 0)
4121 		return -EINVAL;
4122 
4123 	task = get_pid_task(find_vpid(pid), PIDTYPE_PID);
4124 	if (!task)
4125 		return -ENOENT;
4126 
4127 	err = 0;
4128 	file = fget_task(task, fd);
4129 	put_task_struct(task);
4130 	if (!file)
4131 		return -EBADF;
4132 
4133 	if (file->f_op == &bpf_link_fops) {
4134 		struct bpf_link *link = file->private_data;
4135 
4136 		if (link->ops == &bpf_raw_tp_link_lops) {
4137 			struct bpf_raw_tp_link *raw_tp =
4138 				container_of(link, struct bpf_raw_tp_link, link);
4139 			struct bpf_raw_event_map *btp = raw_tp->btp;
4140 
4141 			err = bpf_task_fd_query_copy(attr, uattr,
4142 						     raw_tp->link.prog->aux->id,
4143 						     BPF_FD_TYPE_RAW_TRACEPOINT,
4144 						     btp->tp->name, 0, 0);
4145 			goto put_file;
4146 		}
4147 		goto out_not_supp;
4148 	}
4149 
4150 	event = perf_get_event(file);
4151 	if (!IS_ERR(event)) {
4152 		u64 probe_offset, probe_addr;
4153 		u32 prog_id, fd_type;
4154 		const char *buf;
4155 
4156 		err = bpf_get_perf_event_info(event, &prog_id, &fd_type,
4157 					      &buf, &probe_offset,
4158 					      &probe_addr);
4159 		if (!err)
4160 			err = bpf_task_fd_query_copy(attr, uattr, prog_id,
4161 						     fd_type, buf,
4162 						     probe_offset,
4163 						     probe_addr);
4164 		goto put_file;
4165 	}
4166 
4167 out_not_supp:
4168 	err = -ENOTSUPP;
4169 put_file:
4170 	fput(file);
4171 	return err;
4172 }
4173 
4174 #define BPF_MAP_BATCH_LAST_FIELD batch.flags
4175 
4176 #define BPF_DO_BATCH(fn)			\
4177 	do {					\
4178 		if (!fn) {			\
4179 			err = -ENOTSUPP;	\
4180 			goto err_put;		\
4181 		}				\
4182 		err = fn(map, attr, uattr);	\
4183 	} while (0)
4184 
4185 static int bpf_map_do_batch(const union bpf_attr *attr,
4186 			    union bpf_attr __user *uattr,
4187 			    int cmd)
4188 {
4189 	bool has_read  = cmd == BPF_MAP_LOOKUP_BATCH ||
4190 			 cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH;
4191 	bool has_write = cmd != BPF_MAP_LOOKUP_BATCH;
4192 	struct bpf_map *map;
4193 	int err, ufd;
4194 	struct fd f;
4195 
4196 	if (CHECK_ATTR(BPF_MAP_BATCH))
4197 		return -EINVAL;
4198 
4199 	ufd = attr->batch.map_fd;
4200 	f = fdget(ufd);
4201 	map = __bpf_map_get(f);
4202 	if (IS_ERR(map))
4203 		return PTR_ERR(map);
4204 	if (has_write)
4205 		bpf_map_write_active_inc(map);
4206 	if (has_read && !(map_get_sys_perms(map, f) & FMODE_CAN_READ)) {
4207 		err = -EPERM;
4208 		goto err_put;
4209 	}
4210 	if (has_write && !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
4211 		err = -EPERM;
4212 		goto err_put;
4213 	}
4214 
4215 	if (cmd == BPF_MAP_LOOKUP_BATCH)
4216 		BPF_DO_BATCH(map->ops->map_lookup_batch);
4217 	else if (cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH)
4218 		BPF_DO_BATCH(map->ops->map_lookup_and_delete_batch);
4219 	else if (cmd == BPF_MAP_UPDATE_BATCH)
4220 		BPF_DO_BATCH(map->ops->map_update_batch);
4221 	else
4222 		BPF_DO_BATCH(map->ops->map_delete_batch);
4223 err_put:
4224 	if (has_write)
4225 		bpf_map_write_active_dec(map);
4226 	fdput(f);
4227 	return err;
4228 }
4229 
4230 static int tracing_bpf_link_attach(const union bpf_attr *attr, bpfptr_t uattr,
4231 				   struct bpf_prog *prog)
4232 {
4233 	if (attr->link_create.attach_type != prog->expected_attach_type)
4234 		return -EINVAL;
4235 
4236 	if (prog->expected_attach_type == BPF_TRACE_ITER)
4237 		return bpf_iter_link_attach(attr, uattr, prog);
4238 	else if (prog->type == BPF_PROG_TYPE_EXT)
4239 		return bpf_tracing_prog_attach(prog,
4240 					       attr->link_create.target_fd,
4241 					       attr->link_create.target_btf_id);
4242 	return -EINVAL;
4243 }
4244 
4245 #define BPF_LINK_CREATE_LAST_FIELD link_create.iter_info_len
4246 static int link_create(union bpf_attr *attr, bpfptr_t uattr)
4247 {
4248 	enum bpf_prog_type ptype;
4249 	struct bpf_prog *prog;
4250 	int ret;
4251 
4252 	if (CHECK_ATTR(BPF_LINK_CREATE))
4253 		return -EINVAL;
4254 
4255 	prog = bpf_prog_get(attr->link_create.prog_fd);
4256 	if (IS_ERR(prog))
4257 		return PTR_ERR(prog);
4258 
4259 	ret = bpf_prog_attach_check_attach_type(prog,
4260 						attr->link_create.attach_type);
4261 	if (ret)
4262 		goto out;
4263 
4264 	switch (prog->type) {
4265 	case BPF_PROG_TYPE_EXT:
4266 		ret = tracing_bpf_link_attach(attr, uattr, prog);
4267 		goto out;
4268 	case BPF_PROG_TYPE_PERF_EVENT:
4269 	case BPF_PROG_TYPE_KPROBE:
4270 	case BPF_PROG_TYPE_TRACEPOINT:
4271 		if (attr->link_create.attach_type != BPF_PERF_EVENT) {
4272 			ret = -EINVAL;
4273 			goto out;
4274 		}
4275 		ptype = prog->type;
4276 		break;
4277 	default:
4278 		ptype = attach_type_to_prog_type(attr->link_create.attach_type);
4279 		if (ptype == BPF_PROG_TYPE_UNSPEC || ptype != prog->type) {
4280 			ret = -EINVAL;
4281 			goto out;
4282 		}
4283 		break;
4284 	}
4285 
4286 	switch (ptype) {
4287 	case BPF_PROG_TYPE_CGROUP_SKB:
4288 	case BPF_PROG_TYPE_CGROUP_SOCK:
4289 	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
4290 	case BPF_PROG_TYPE_SOCK_OPS:
4291 	case BPF_PROG_TYPE_CGROUP_DEVICE:
4292 	case BPF_PROG_TYPE_CGROUP_SYSCTL:
4293 	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
4294 		ret = cgroup_bpf_link_attach(attr, prog);
4295 		break;
4296 	case BPF_PROG_TYPE_TRACING:
4297 		ret = tracing_bpf_link_attach(attr, uattr, prog);
4298 		break;
4299 	case BPF_PROG_TYPE_FLOW_DISSECTOR:
4300 	case BPF_PROG_TYPE_SK_LOOKUP:
4301 		ret = netns_bpf_link_create(attr, prog);
4302 		break;
4303 #ifdef CONFIG_NET
4304 	case BPF_PROG_TYPE_XDP:
4305 		ret = bpf_xdp_link_attach(attr, prog);
4306 		break;
4307 #endif
4308 #ifdef CONFIG_PERF_EVENTS
4309 	case BPF_PROG_TYPE_PERF_EVENT:
4310 	case BPF_PROG_TYPE_TRACEPOINT:
4311 	case BPF_PROG_TYPE_KPROBE:
4312 		ret = bpf_perf_link_attach(attr, prog);
4313 		break;
4314 #endif
4315 	default:
4316 		ret = -EINVAL;
4317 	}
4318 
4319 out:
4320 	if (ret < 0)
4321 		bpf_prog_put(prog);
4322 	return ret;
4323 }
4324 
4325 #define BPF_LINK_UPDATE_LAST_FIELD link_update.old_prog_fd
4326 
4327 static int link_update(union bpf_attr *attr)
4328 {
4329 	struct bpf_prog *old_prog = NULL, *new_prog;
4330 	struct bpf_link *link;
4331 	u32 flags;
4332 	int ret;
4333 
4334 	if (CHECK_ATTR(BPF_LINK_UPDATE))
4335 		return -EINVAL;
4336 
4337 	flags = attr->link_update.flags;
4338 	if (flags & ~BPF_F_REPLACE)
4339 		return -EINVAL;
4340 
4341 	link = bpf_link_get_from_fd(attr->link_update.link_fd);
4342 	if (IS_ERR(link))
4343 		return PTR_ERR(link);
4344 
4345 	new_prog = bpf_prog_get(attr->link_update.new_prog_fd);
4346 	if (IS_ERR(new_prog)) {
4347 		ret = PTR_ERR(new_prog);
4348 		goto out_put_link;
4349 	}
4350 
4351 	if (flags & BPF_F_REPLACE) {
4352 		old_prog = bpf_prog_get(attr->link_update.old_prog_fd);
4353 		if (IS_ERR(old_prog)) {
4354 			ret = PTR_ERR(old_prog);
4355 			old_prog = NULL;
4356 			goto out_put_progs;
4357 		}
4358 	} else if (attr->link_update.old_prog_fd) {
4359 		ret = -EINVAL;
4360 		goto out_put_progs;
4361 	}
4362 
4363 	if (link->ops->update_prog)
4364 		ret = link->ops->update_prog(link, new_prog, old_prog);
4365 	else
4366 		ret = -EINVAL;
4367 
4368 out_put_progs:
4369 	if (old_prog)
4370 		bpf_prog_put(old_prog);
4371 	if (ret)
4372 		bpf_prog_put(new_prog);
4373 out_put_link:
4374 	bpf_link_put(link);
4375 	return ret;
4376 }
4377 
4378 #define BPF_LINK_DETACH_LAST_FIELD link_detach.link_fd
4379 
4380 static int link_detach(union bpf_attr *attr)
4381 {
4382 	struct bpf_link *link;
4383 	int ret;
4384 
4385 	if (CHECK_ATTR(BPF_LINK_DETACH))
4386 		return -EINVAL;
4387 
4388 	link = bpf_link_get_from_fd(attr->link_detach.link_fd);
4389 	if (IS_ERR(link))
4390 		return PTR_ERR(link);
4391 
4392 	if (link->ops->detach)
4393 		ret = link->ops->detach(link);
4394 	else
4395 		ret = -EOPNOTSUPP;
4396 
4397 	bpf_link_put(link);
4398 	return ret;
4399 }
4400 
4401 static struct bpf_link *bpf_link_inc_not_zero(struct bpf_link *link)
4402 {
4403 	return atomic64_fetch_add_unless(&link->refcnt, 1, 0) ? link : ERR_PTR(-ENOENT);
4404 }
4405 
4406 struct bpf_link *bpf_link_by_id(u32 id)
4407 {
4408 	struct bpf_link *link;
4409 
4410 	if (!id)
4411 		return ERR_PTR(-ENOENT);
4412 
4413 	spin_lock_bh(&link_idr_lock);
4414 	/* before link is "settled", ID is 0, pretend it doesn't exist yet */
4415 	link = idr_find(&link_idr, id);
4416 	if (link) {
4417 		if (link->id)
4418 			link = bpf_link_inc_not_zero(link);
4419 		else
4420 			link = ERR_PTR(-EAGAIN);
4421 	} else {
4422 		link = ERR_PTR(-ENOENT);
4423 	}
4424 	spin_unlock_bh(&link_idr_lock);
4425 	return link;
4426 }
4427 
4428 #define BPF_LINK_GET_FD_BY_ID_LAST_FIELD link_id
4429 
4430 static int bpf_link_get_fd_by_id(const union bpf_attr *attr)
4431 {
4432 	struct bpf_link *link;
4433 	u32 id = attr->link_id;
4434 	int fd;
4435 
4436 	if (CHECK_ATTR(BPF_LINK_GET_FD_BY_ID))
4437 		return -EINVAL;
4438 
4439 	if (!capable(CAP_SYS_ADMIN))
4440 		return -EPERM;
4441 
4442 	link = bpf_link_by_id(id);
4443 	if (IS_ERR(link))
4444 		return PTR_ERR(link);
4445 
4446 	fd = bpf_link_new_fd(link);
4447 	if (fd < 0)
4448 		bpf_link_put(link);
4449 
4450 	return fd;
4451 }
4452 
4453 DEFINE_MUTEX(bpf_stats_enabled_mutex);
4454 
4455 static int bpf_stats_release(struct inode *inode, struct file *file)
4456 {
4457 	mutex_lock(&bpf_stats_enabled_mutex);
4458 	static_key_slow_dec(&bpf_stats_enabled_key.key);
4459 	mutex_unlock(&bpf_stats_enabled_mutex);
4460 	return 0;
4461 }
4462 
4463 static const struct file_operations bpf_stats_fops = {
4464 	.release = bpf_stats_release,
4465 };
4466 
4467 static int bpf_enable_runtime_stats(void)
4468 {
4469 	int fd;
4470 
4471 	mutex_lock(&bpf_stats_enabled_mutex);
4472 
4473 	/* Set a very high limit to avoid overflow */
4474 	if (static_key_count(&bpf_stats_enabled_key.key) > INT_MAX / 2) {
4475 		mutex_unlock(&bpf_stats_enabled_mutex);
4476 		return -EBUSY;
4477 	}
4478 
4479 	fd = anon_inode_getfd("bpf-stats", &bpf_stats_fops, NULL, O_CLOEXEC);
4480 	if (fd >= 0)
4481 		static_key_slow_inc(&bpf_stats_enabled_key.key);
4482 
4483 	mutex_unlock(&bpf_stats_enabled_mutex);
4484 	return fd;
4485 }
4486 
4487 #define BPF_ENABLE_STATS_LAST_FIELD enable_stats.type
4488 
4489 static int bpf_enable_stats(union bpf_attr *attr)
4490 {
4491 
4492 	if (CHECK_ATTR(BPF_ENABLE_STATS))
4493 		return -EINVAL;
4494 
4495 	if (!capable(CAP_SYS_ADMIN))
4496 		return -EPERM;
4497 
4498 	switch (attr->enable_stats.type) {
4499 	case BPF_STATS_RUN_TIME:
4500 		return bpf_enable_runtime_stats();
4501 	default:
4502 		break;
4503 	}
4504 	return -EINVAL;
4505 }
4506 
4507 #define BPF_ITER_CREATE_LAST_FIELD iter_create.flags
4508 
4509 static int bpf_iter_create(union bpf_attr *attr)
4510 {
4511 	struct bpf_link *link;
4512 	int err;
4513 
4514 	if (CHECK_ATTR(BPF_ITER_CREATE))
4515 		return -EINVAL;
4516 
4517 	if (attr->iter_create.flags)
4518 		return -EINVAL;
4519 
4520 	link = bpf_link_get_from_fd(attr->iter_create.link_fd);
4521 	if (IS_ERR(link))
4522 		return PTR_ERR(link);
4523 
4524 	err = bpf_iter_new_fd(link);
4525 	bpf_link_put(link);
4526 
4527 	return err;
4528 }
4529 
4530 #define BPF_PROG_BIND_MAP_LAST_FIELD prog_bind_map.flags
4531 
4532 static int bpf_prog_bind_map(union bpf_attr *attr)
4533 {
4534 	struct bpf_prog *prog;
4535 	struct bpf_map *map;
4536 	struct bpf_map **used_maps_old, **used_maps_new;
4537 	int i, ret = 0;
4538 
4539 	if (CHECK_ATTR(BPF_PROG_BIND_MAP))
4540 		return -EINVAL;
4541 
4542 	if (attr->prog_bind_map.flags)
4543 		return -EINVAL;
4544 
4545 	prog = bpf_prog_get(attr->prog_bind_map.prog_fd);
4546 	if (IS_ERR(prog))
4547 		return PTR_ERR(prog);
4548 
4549 	map = bpf_map_get(attr->prog_bind_map.map_fd);
4550 	if (IS_ERR(map)) {
4551 		ret = PTR_ERR(map);
4552 		goto out_prog_put;
4553 	}
4554 
4555 	mutex_lock(&prog->aux->used_maps_mutex);
4556 
4557 	used_maps_old = prog->aux->used_maps;
4558 
4559 	for (i = 0; i < prog->aux->used_map_cnt; i++)
4560 		if (used_maps_old[i] == map) {
4561 			bpf_map_put(map);
4562 			goto out_unlock;
4563 		}
4564 
4565 	used_maps_new = kmalloc_array(prog->aux->used_map_cnt + 1,
4566 				      sizeof(used_maps_new[0]),
4567 				      GFP_KERNEL);
4568 	if (!used_maps_new) {
4569 		ret = -ENOMEM;
4570 		goto out_unlock;
4571 	}
4572 
4573 	memcpy(used_maps_new, used_maps_old,
4574 	       sizeof(used_maps_old[0]) * prog->aux->used_map_cnt);
4575 	used_maps_new[prog->aux->used_map_cnt] = map;
4576 
4577 	prog->aux->used_map_cnt++;
4578 	prog->aux->used_maps = used_maps_new;
4579 
4580 	kfree(used_maps_old);
4581 
4582 out_unlock:
4583 	mutex_unlock(&prog->aux->used_maps_mutex);
4584 
4585 	if (ret)
4586 		bpf_map_put(map);
4587 out_prog_put:
4588 	bpf_prog_put(prog);
4589 	return ret;
4590 }
4591 
4592 static int __sys_bpf(int cmd, bpfptr_t uattr, unsigned int size)
4593 {
4594 	union bpf_attr attr;
4595 	int err;
4596 
4597 	if (sysctl_unprivileged_bpf_disabled && !bpf_capable())
4598 		return -EPERM;
4599 
4600 	err = bpf_check_uarg_tail_zero(uattr, sizeof(attr), size);
4601 	if (err)
4602 		return err;
4603 	size = min_t(u32, size, sizeof(attr));
4604 
4605 	/* copy attributes from user space, may be less than sizeof(bpf_attr) */
4606 	memset(&attr, 0, sizeof(attr));
4607 	if (copy_from_bpfptr(&attr, uattr, size) != 0)
4608 		return -EFAULT;
4609 
4610 	err = security_bpf(cmd, &attr, size);
4611 	if (err < 0)
4612 		return err;
4613 
4614 	switch (cmd) {
4615 	case BPF_MAP_CREATE:
4616 		err = map_create(&attr);
4617 		break;
4618 	case BPF_MAP_LOOKUP_ELEM:
4619 		err = map_lookup_elem(&attr);
4620 		break;
4621 	case BPF_MAP_UPDATE_ELEM:
4622 		err = map_update_elem(&attr, uattr);
4623 		break;
4624 	case BPF_MAP_DELETE_ELEM:
4625 		err = map_delete_elem(&attr);
4626 		break;
4627 	case BPF_MAP_GET_NEXT_KEY:
4628 		err = map_get_next_key(&attr);
4629 		break;
4630 	case BPF_MAP_FREEZE:
4631 		err = map_freeze(&attr);
4632 		break;
4633 	case BPF_PROG_LOAD:
4634 		err = bpf_prog_load(&attr, uattr);
4635 		break;
4636 	case BPF_OBJ_PIN:
4637 		err = bpf_obj_pin(&attr);
4638 		break;
4639 	case BPF_OBJ_GET:
4640 		err = bpf_obj_get(&attr);
4641 		break;
4642 	case BPF_PROG_ATTACH:
4643 		err = bpf_prog_attach(&attr);
4644 		break;
4645 	case BPF_PROG_DETACH:
4646 		err = bpf_prog_detach(&attr);
4647 		break;
4648 	case BPF_PROG_QUERY:
4649 		err = bpf_prog_query(&attr, uattr.user);
4650 		break;
4651 	case BPF_PROG_TEST_RUN:
4652 		err = bpf_prog_test_run(&attr, uattr.user);
4653 		break;
4654 	case BPF_PROG_GET_NEXT_ID:
4655 		err = bpf_obj_get_next_id(&attr, uattr.user,
4656 					  &prog_idr, &prog_idr_lock);
4657 		break;
4658 	case BPF_MAP_GET_NEXT_ID:
4659 		err = bpf_obj_get_next_id(&attr, uattr.user,
4660 					  &map_idr, &map_idr_lock);
4661 		break;
4662 	case BPF_BTF_GET_NEXT_ID:
4663 		err = bpf_obj_get_next_id(&attr, uattr.user,
4664 					  &btf_idr, &btf_idr_lock);
4665 		break;
4666 	case BPF_PROG_GET_FD_BY_ID:
4667 		err = bpf_prog_get_fd_by_id(&attr);
4668 		break;
4669 	case BPF_MAP_GET_FD_BY_ID:
4670 		err = bpf_map_get_fd_by_id(&attr);
4671 		break;
4672 	case BPF_OBJ_GET_INFO_BY_FD:
4673 		err = bpf_obj_get_info_by_fd(&attr, uattr.user);
4674 		break;
4675 	case BPF_RAW_TRACEPOINT_OPEN:
4676 		err = bpf_raw_tracepoint_open(&attr);
4677 		break;
4678 	case BPF_BTF_LOAD:
4679 		err = bpf_btf_load(&attr, uattr);
4680 		break;
4681 	case BPF_BTF_GET_FD_BY_ID:
4682 		err = bpf_btf_get_fd_by_id(&attr);
4683 		break;
4684 	case BPF_TASK_FD_QUERY:
4685 		err = bpf_task_fd_query(&attr, uattr.user);
4686 		break;
4687 	case BPF_MAP_LOOKUP_AND_DELETE_ELEM:
4688 		err = map_lookup_and_delete_elem(&attr);
4689 		break;
4690 	case BPF_MAP_LOOKUP_BATCH:
4691 		err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_LOOKUP_BATCH);
4692 		break;
4693 	case BPF_MAP_LOOKUP_AND_DELETE_BATCH:
4694 		err = bpf_map_do_batch(&attr, uattr.user,
4695 				       BPF_MAP_LOOKUP_AND_DELETE_BATCH);
4696 		break;
4697 	case BPF_MAP_UPDATE_BATCH:
4698 		err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_UPDATE_BATCH);
4699 		break;
4700 	case BPF_MAP_DELETE_BATCH:
4701 		err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_DELETE_BATCH);
4702 		break;
4703 	case BPF_LINK_CREATE:
4704 		err = link_create(&attr, uattr);
4705 		break;
4706 	case BPF_LINK_UPDATE:
4707 		err = link_update(&attr);
4708 		break;
4709 	case BPF_LINK_GET_FD_BY_ID:
4710 		err = bpf_link_get_fd_by_id(&attr);
4711 		break;
4712 	case BPF_LINK_GET_NEXT_ID:
4713 		err = bpf_obj_get_next_id(&attr, uattr.user,
4714 					  &link_idr, &link_idr_lock);
4715 		break;
4716 	case BPF_ENABLE_STATS:
4717 		err = bpf_enable_stats(&attr);
4718 		break;
4719 	case BPF_ITER_CREATE:
4720 		err = bpf_iter_create(&attr);
4721 		break;
4722 	case BPF_LINK_DETACH:
4723 		err = link_detach(&attr);
4724 		break;
4725 	case BPF_PROG_BIND_MAP:
4726 		err = bpf_prog_bind_map(&attr);
4727 		break;
4728 	default:
4729 		err = -EINVAL;
4730 		break;
4731 	}
4732 
4733 	return err;
4734 }
4735 
4736 SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size)
4737 {
4738 	return __sys_bpf(cmd, USER_BPFPTR(uattr), size);
4739 }
4740 
4741 static bool syscall_prog_is_valid_access(int off, int size,
4742 					 enum bpf_access_type type,
4743 					 const struct bpf_prog *prog,
4744 					 struct bpf_insn_access_aux *info)
4745 {
4746 	if (off < 0 || off >= U16_MAX)
4747 		return false;
4748 	if (off % size != 0)
4749 		return false;
4750 	return true;
4751 }
4752 
4753 BPF_CALL_3(bpf_sys_bpf, int, cmd, void *, attr, u32, attr_size)
4754 {
4755 	switch (cmd) {
4756 	case BPF_MAP_CREATE:
4757 	case BPF_MAP_UPDATE_ELEM:
4758 	case BPF_MAP_FREEZE:
4759 	case BPF_PROG_LOAD:
4760 	case BPF_BTF_LOAD:
4761 		break;
4762 	/* case BPF_PROG_TEST_RUN:
4763 	 * is not part of this list to prevent recursive test_run
4764 	 */
4765 	default:
4766 		return -EINVAL;
4767 	}
4768 	return __sys_bpf(cmd, KERNEL_BPFPTR(attr), attr_size);
4769 }
4770 
4771 static const struct bpf_func_proto bpf_sys_bpf_proto = {
4772 	.func		= bpf_sys_bpf,
4773 	.gpl_only	= false,
4774 	.ret_type	= RET_INTEGER,
4775 	.arg1_type	= ARG_ANYTHING,
4776 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
4777 	.arg3_type	= ARG_CONST_SIZE,
4778 };
4779 
4780 const struct bpf_func_proto * __weak
4781 tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
4782 {
4783 	return bpf_base_func_proto(func_id);
4784 }
4785 
4786 BPF_CALL_1(bpf_sys_close, u32, fd)
4787 {
4788 	/* When bpf program calls this helper there should not be
4789 	 * an fdget() without matching completed fdput().
4790 	 * This helper is allowed in the following callchain only:
4791 	 * sys_bpf->prog_test_run->bpf_prog->bpf_sys_close
4792 	 */
4793 	return close_fd(fd);
4794 }
4795 
4796 static const struct bpf_func_proto bpf_sys_close_proto = {
4797 	.func		= bpf_sys_close,
4798 	.gpl_only	= false,
4799 	.ret_type	= RET_INTEGER,
4800 	.arg1_type	= ARG_ANYTHING,
4801 };
4802 
4803 BPF_CALL_4(bpf_kallsyms_lookup_name, const char *, name, int, name_sz, int, flags, u64 *, res)
4804 {
4805 	if (flags)
4806 		return -EINVAL;
4807 
4808 	if (name_sz <= 1 || name[name_sz - 1])
4809 		return -EINVAL;
4810 
4811 	if (!bpf_dump_raw_ok(current_cred()))
4812 		return -EPERM;
4813 
4814 	*res = kallsyms_lookup_name(name);
4815 	return *res ? 0 : -ENOENT;
4816 }
4817 
4818 const struct bpf_func_proto bpf_kallsyms_lookup_name_proto = {
4819 	.func		= bpf_kallsyms_lookup_name,
4820 	.gpl_only	= false,
4821 	.ret_type	= RET_INTEGER,
4822 	.arg1_type	= ARG_PTR_TO_MEM,
4823 	.arg2_type	= ARG_CONST_SIZE_OR_ZERO,
4824 	.arg3_type	= ARG_ANYTHING,
4825 	.arg4_type	= ARG_PTR_TO_LONG,
4826 };
4827 
4828 static const struct bpf_func_proto *
4829 syscall_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
4830 {
4831 	switch (func_id) {
4832 	case BPF_FUNC_sys_bpf:
4833 		return &bpf_sys_bpf_proto;
4834 	case BPF_FUNC_btf_find_by_name_kind:
4835 		return &bpf_btf_find_by_name_kind_proto;
4836 	case BPF_FUNC_sys_close:
4837 		return &bpf_sys_close_proto;
4838 	case BPF_FUNC_kallsyms_lookup_name:
4839 		return &bpf_kallsyms_lookup_name_proto;
4840 	default:
4841 		return tracing_prog_func_proto(func_id, prog);
4842 	}
4843 }
4844 
4845 const struct bpf_verifier_ops bpf_syscall_verifier_ops = {
4846 	.get_func_proto  = syscall_prog_func_proto,
4847 	.is_valid_access = syscall_prog_is_valid_access,
4848 };
4849 
4850 const struct bpf_prog_ops bpf_syscall_prog_ops = {
4851 	.test_run = bpf_prog_test_run_syscall,
4852 };
4853