xref: /openbmc/linux/kernel/bpf/syscall.c (revision c4a11bf4)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
3  */
4 #include <linux/bpf.h>
5 #include <linux/bpf_trace.h>
6 #include <linux/bpf_lirc.h>
7 #include <linux/bpf_verifier.h>
8 #include <linux/btf.h>
9 #include <linux/syscalls.h>
10 #include <linux/slab.h>
11 #include <linux/sched/signal.h>
12 #include <linux/vmalloc.h>
13 #include <linux/mmzone.h>
14 #include <linux/anon_inodes.h>
15 #include <linux/fdtable.h>
16 #include <linux/file.h>
17 #include <linux/fs.h>
18 #include <linux/license.h>
19 #include <linux/filter.h>
20 #include <linux/kernel.h>
21 #include <linux/idr.h>
22 #include <linux/cred.h>
23 #include <linux/timekeeping.h>
24 #include <linux/ctype.h>
25 #include <linux/nospec.h>
26 #include <linux/audit.h>
27 #include <uapi/linux/btf.h>
28 #include <linux/pgtable.h>
29 #include <linux/bpf_lsm.h>
30 #include <linux/poll.h>
31 #include <linux/bpf-netns.h>
32 #include <linux/rcupdate_trace.h>
33 #include <linux/memcontrol.h>
34 
35 #define IS_FD_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || \
36 			  (map)->map_type == BPF_MAP_TYPE_CGROUP_ARRAY || \
37 			  (map)->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS)
38 #define IS_FD_PROG_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PROG_ARRAY)
39 #define IS_FD_HASH(map) ((map)->map_type == BPF_MAP_TYPE_HASH_OF_MAPS)
40 #define IS_FD_MAP(map) (IS_FD_ARRAY(map) || IS_FD_PROG_ARRAY(map) || \
41 			IS_FD_HASH(map))
42 
43 #define BPF_OBJ_FLAG_MASK   (BPF_F_RDONLY | BPF_F_WRONLY)
44 
45 DEFINE_PER_CPU(int, bpf_prog_active);
46 static DEFINE_IDR(prog_idr);
47 static DEFINE_SPINLOCK(prog_idr_lock);
48 static DEFINE_IDR(map_idr);
49 static DEFINE_SPINLOCK(map_idr_lock);
50 static DEFINE_IDR(link_idr);
51 static DEFINE_SPINLOCK(link_idr_lock);
52 
53 int sysctl_unprivileged_bpf_disabled __read_mostly =
54 	IS_BUILTIN(CONFIG_BPF_UNPRIV_DEFAULT_OFF) ? 2 : 0;
55 
56 static const struct bpf_map_ops * const bpf_map_types[] = {
57 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type)
58 #define BPF_MAP_TYPE(_id, _ops) \
59 	[_id] = &_ops,
60 #define BPF_LINK_TYPE(_id, _name)
61 #include <linux/bpf_types.h>
62 #undef BPF_PROG_TYPE
63 #undef BPF_MAP_TYPE
64 #undef BPF_LINK_TYPE
65 };
66 
67 /*
68  * If we're handed a bigger struct than we know of, ensure all the unknown bits
69  * are 0 - i.e. new user-space does not rely on any kernel feature extensions
70  * we don't know about yet.
71  *
72  * There is a ToCToU between this function call and the following
73  * copy_from_user() call. However, this is not a concern since this function is
74  * meant to be a future-proofing of bits.
75  */
76 int bpf_check_uarg_tail_zero(bpfptr_t uaddr,
77 			     size_t expected_size,
78 			     size_t actual_size)
79 {
80 	int res;
81 
82 	if (unlikely(actual_size > PAGE_SIZE))	/* silly large */
83 		return -E2BIG;
84 
85 	if (actual_size <= expected_size)
86 		return 0;
87 
88 	if (uaddr.is_kernel)
89 		res = memchr_inv(uaddr.kernel + expected_size, 0,
90 				 actual_size - expected_size) == NULL;
91 	else
92 		res = check_zeroed_user(uaddr.user + expected_size,
93 					actual_size - expected_size);
94 	if (res < 0)
95 		return res;
96 	return res ? 0 : -E2BIG;
97 }
98 
99 const struct bpf_map_ops bpf_map_offload_ops = {
100 	.map_meta_equal = bpf_map_meta_equal,
101 	.map_alloc = bpf_map_offload_map_alloc,
102 	.map_free = bpf_map_offload_map_free,
103 	.map_check_btf = map_check_no_btf,
104 };
105 
106 static struct bpf_map *find_and_alloc_map(union bpf_attr *attr)
107 {
108 	const struct bpf_map_ops *ops;
109 	u32 type = attr->map_type;
110 	struct bpf_map *map;
111 	int err;
112 
113 	if (type >= ARRAY_SIZE(bpf_map_types))
114 		return ERR_PTR(-EINVAL);
115 	type = array_index_nospec(type, ARRAY_SIZE(bpf_map_types));
116 	ops = bpf_map_types[type];
117 	if (!ops)
118 		return ERR_PTR(-EINVAL);
119 
120 	if (ops->map_alloc_check) {
121 		err = ops->map_alloc_check(attr);
122 		if (err)
123 			return ERR_PTR(err);
124 	}
125 	if (attr->map_ifindex)
126 		ops = &bpf_map_offload_ops;
127 	map = ops->map_alloc(attr);
128 	if (IS_ERR(map))
129 		return map;
130 	map->ops = ops;
131 	map->map_type = type;
132 	return map;
133 }
134 
135 static u32 bpf_map_value_size(const struct bpf_map *map)
136 {
137 	if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
138 	    map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH ||
139 	    map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY ||
140 	    map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE)
141 		return round_up(map->value_size, 8) * num_possible_cpus();
142 	else if (IS_FD_MAP(map))
143 		return sizeof(u32);
144 	else
145 		return  map->value_size;
146 }
147 
148 static void maybe_wait_bpf_programs(struct bpf_map *map)
149 {
150 	/* Wait for any running BPF programs to complete so that
151 	 * userspace, when we return to it, knows that all programs
152 	 * that could be running use the new map value.
153 	 */
154 	if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS ||
155 	    map->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS)
156 		synchronize_rcu();
157 }
158 
159 static int bpf_map_update_value(struct bpf_map *map, struct fd f, void *key,
160 				void *value, __u64 flags)
161 {
162 	int err;
163 
164 	/* Need to create a kthread, thus must support schedule */
165 	if (bpf_map_is_dev_bound(map)) {
166 		return bpf_map_offload_update_elem(map, key, value, flags);
167 	} else if (map->map_type == BPF_MAP_TYPE_CPUMAP ||
168 		   map->map_type == BPF_MAP_TYPE_STRUCT_OPS) {
169 		return map->ops->map_update_elem(map, key, value, flags);
170 	} else if (map->map_type == BPF_MAP_TYPE_SOCKHASH ||
171 		   map->map_type == BPF_MAP_TYPE_SOCKMAP) {
172 		return sock_map_update_elem_sys(map, key, value, flags);
173 	} else if (IS_FD_PROG_ARRAY(map)) {
174 		return bpf_fd_array_map_update_elem(map, f.file, key, value,
175 						    flags);
176 	}
177 
178 	bpf_disable_instrumentation();
179 	if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
180 	    map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
181 		err = bpf_percpu_hash_update(map, key, value, flags);
182 	} else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) {
183 		err = bpf_percpu_array_update(map, key, value, flags);
184 	} else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) {
185 		err = bpf_percpu_cgroup_storage_update(map, key, value,
186 						       flags);
187 	} else if (IS_FD_ARRAY(map)) {
188 		rcu_read_lock();
189 		err = bpf_fd_array_map_update_elem(map, f.file, key, value,
190 						   flags);
191 		rcu_read_unlock();
192 	} else if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) {
193 		rcu_read_lock();
194 		err = bpf_fd_htab_map_update_elem(map, f.file, key, value,
195 						  flags);
196 		rcu_read_unlock();
197 	} else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) {
198 		/* rcu_read_lock() is not needed */
199 		err = bpf_fd_reuseport_array_update_elem(map, key, value,
200 							 flags);
201 	} else if (map->map_type == BPF_MAP_TYPE_QUEUE ||
202 		   map->map_type == BPF_MAP_TYPE_STACK ||
203 		   map->map_type == BPF_MAP_TYPE_BLOOM_FILTER) {
204 		err = map->ops->map_push_elem(map, value, flags);
205 	} else {
206 		rcu_read_lock();
207 		err = map->ops->map_update_elem(map, key, value, flags);
208 		rcu_read_unlock();
209 	}
210 	bpf_enable_instrumentation();
211 	maybe_wait_bpf_programs(map);
212 
213 	return err;
214 }
215 
216 static int bpf_map_copy_value(struct bpf_map *map, void *key, void *value,
217 			      __u64 flags)
218 {
219 	void *ptr;
220 	int err;
221 
222 	if (bpf_map_is_dev_bound(map))
223 		return bpf_map_offload_lookup_elem(map, key, value);
224 
225 	bpf_disable_instrumentation();
226 	if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
227 	    map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
228 		err = bpf_percpu_hash_copy(map, key, value);
229 	} else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) {
230 		err = bpf_percpu_array_copy(map, key, value);
231 	} else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) {
232 		err = bpf_percpu_cgroup_storage_copy(map, key, value);
233 	} else if (map->map_type == BPF_MAP_TYPE_STACK_TRACE) {
234 		err = bpf_stackmap_copy(map, key, value);
235 	} else if (IS_FD_ARRAY(map) || IS_FD_PROG_ARRAY(map)) {
236 		err = bpf_fd_array_map_lookup_elem(map, key, value);
237 	} else if (IS_FD_HASH(map)) {
238 		err = bpf_fd_htab_map_lookup_elem(map, key, value);
239 	} else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) {
240 		err = bpf_fd_reuseport_array_lookup_elem(map, key, value);
241 	} else if (map->map_type == BPF_MAP_TYPE_QUEUE ||
242 		   map->map_type == BPF_MAP_TYPE_STACK ||
243 		   map->map_type == BPF_MAP_TYPE_BLOOM_FILTER) {
244 		err = map->ops->map_peek_elem(map, value);
245 	} else if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS) {
246 		/* struct_ops map requires directly updating "value" */
247 		err = bpf_struct_ops_map_sys_lookup_elem(map, key, value);
248 	} else {
249 		rcu_read_lock();
250 		if (map->ops->map_lookup_elem_sys_only)
251 			ptr = map->ops->map_lookup_elem_sys_only(map, key);
252 		else
253 			ptr = map->ops->map_lookup_elem(map, key);
254 		if (IS_ERR(ptr)) {
255 			err = PTR_ERR(ptr);
256 		} else if (!ptr) {
257 			err = -ENOENT;
258 		} else {
259 			err = 0;
260 			if (flags & BPF_F_LOCK)
261 				/* lock 'ptr' and copy everything but lock */
262 				copy_map_value_locked(map, value, ptr, true);
263 			else
264 				copy_map_value(map, value, ptr);
265 			/* mask lock and timer, since value wasn't zero inited */
266 			check_and_init_map_value(map, value);
267 		}
268 		rcu_read_unlock();
269 	}
270 
271 	bpf_enable_instrumentation();
272 	maybe_wait_bpf_programs(map);
273 
274 	return err;
275 }
276 
277 /* Please, do not use this function outside from the map creation path
278  * (e.g. in map update path) without taking care of setting the active
279  * memory cgroup (see at bpf_map_kmalloc_node() for example).
280  */
281 static void *__bpf_map_area_alloc(u64 size, int numa_node, bool mmapable)
282 {
283 	/* We really just want to fail instead of triggering OOM killer
284 	 * under memory pressure, therefore we set __GFP_NORETRY to kmalloc,
285 	 * which is used for lower order allocation requests.
286 	 *
287 	 * It has been observed that higher order allocation requests done by
288 	 * vmalloc with __GFP_NORETRY being set might fail due to not trying
289 	 * to reclaim memory from the page cache, thus we set
290 	 * __GFP_RETRY_MAYFAIL to avoid such situations.
291 	 */
292 
293 	const gfp_t gfp = __GFP_NOWARN | __GFP_ZERO | __GFP_ACCOUNT;
294 	unsigned int flags = 0;
295 	unsigned long align = 1;
296 	void *area;
297 
298 	if (size >= SIZE_MAX)
299 		return NULL;
300 
301 	/* kmalloc()'ed memory can't be mmap()'ed */
302 	if (mmapable) {
303 		BUG_ON(!PAGE_ALIGNED(size));
304 		align = SHMLBA;
305 		flags = VM_USERMAP;
306 	} else if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) {
307 		area = kmalloc_node(size, gfp | GFP_USER | __GFP_NORETRY,
308 				    numa_node);
309 		if (area != NULL)
310 			return area;
311 	}
312 
313 	return __vmalloc_node_range(size, align, VMALLOC_START, VMALLOC_END,
314 			gfp | GFP_KERNEL | __GFP_RETRY_MAYFAIL, PAGE_KERNEL,
315 			flags, numa_node, __builtin_return_address(0));
316 }
317 
318 void *bpf_map_area_alloc(u64 size, int numa_node)
319 {
320 	return __bpf_map_area_alloc(size, numa_node, false);
321 }
322 
323 void *bpf_map_area_mmapable_alloc(u64 size, int numa_node)
324 {
325 	return __bpf_map_area_alloc(size, numa_node, true);
326 }
327 
328 void bpf_map_area_free(void *area)
329 {
330 	kvfree(area);
331 }
332 
333 static u32 bpf_map_flags_retain_permanent(u32 flags)
334 {
335 	/* Some map creation flags are not tied to the map object but
336 	 * rather to the map fd instead, so they have no meaning upon
337 	 * map object inspection since multiple file descriptors with
338 	 * different (access) properties can exist here. Thus, given
339 	 * this has zero meaning for the map itself, lets clear these
340 	 * from here.
341 	 */
342 	return flags & ~(BPF_F_RDONLY | BPF_F_WRONLY);
343 }
344 
345 void bpf_map_init_from_attr(struct bpf_map *map, union bpf_attr *attr)
346 {
347 	map->map_type = attr->map_type;
348 	map->key_size = attr->key_size;
349 	map->value_size = attr->value_size;
350 	map->max_entries = attr->max_entries;
351 	map->map_flags = bpf_map_flags_retain_permanent(attr->map_flags);
352 	map->numa_node = bpf_map_attr_numa_node(attr);
353 	map->map_extra = attr->map_extra;
354 }
355 
356 static int bpf_map_alloc_id(struct bpf_map *map)
357 {
358 	int id;
359 
360 	idr_preload(GFP_KERNEL);
361 	spin_lock_bh(&map_idr_lock);
362 	id = idr_alloc_cyclic(&map_idr, map, 1, INT_MAX, GFP_ATOMIC);
363 	if (id > 0)
364 		map->id = id;
365 	spin_unlock_bh(&map_idr_lock);
366 	idr_preload_end();
367 
368 	if (WARN_ON_ONCE(!id))
369 		return -ENOSPC;
370 
371 	return id > 0 ? 0 : id;
372 }
373 
374 void bpf_map_free_id(struct bpf_map *map, bool do_idr_lock)
375 {
376 	unsigned long flags;
377 
378 	/* Offloaded maps are removed from the IDR store when their device
379 	 * disappears - even if someone holds an fd to them they are unusable,
380 	 * the memory is gone, all ops will fail; they are simply waiting for
381 	 * refcnt to drop to be freed.
382 	 */
383 	if (!map->id)
384 		return;
385 
386 	if (do_idr_lock)
387 		spin_lock_irqsave(&map_idr_lock, flags);
388 	else
389 		__acquire(&map_idr_lock);
390 
391 	idr_remove(&map_idr, map->id);
392 	map->id = 0;
393 
394 	if (do_idr_lock)
395 		spin_unlock_irqrestore(&map_idr_lock, flags);
396 	else
397 		__release(&map_idr_lock);
398 }
399 
400 #ifdef CONFIG_MEMCG_KMEM
401 static void bpf_map_save_memcg(struct bpf_map *map)
402 {
403 	map->memcg = get_mem_cgroup_from_mm(current->mm);
404 }
405 
406 static void bpf_map_release_memcg(struct bpf_map *map)
407 {
408 	mem_cgroup_put(map->memcg);
409 }
410 
411 void *bpf_map_kmalloc_node(const struct bpf_map *map, size_t size, gfp_t flags,
412 			   int node)
413 {
414 	struct mem_cgroup *old_memcg;
415 	void *ptr;
416 
417 	old_memcg = set_active_memcg(map->memcg);
418 	ptr = kmalloc_node(size, flags | __GFP_ACCOUNT, node);
419 	set_active_memcg(old_memcg);
420 
421 	return ptr;
422 }
423 
424 void *bpf_map_kzalloc(const struct bpf_map *map, size_t size, gfp_t flags)
425 {
426 	struct mem_cgroup *old_memcg;
427 	void *ptr;
428 
429 	old_memcg = set_active_memcg(map->memcg);
430 	ptr = kzalloc(size, flags | __GFP_ACCOUNT);
431 	set_active_memcg(old_memcg);
432 
433 	return ptr;
434 }
435 
436 void __percpu *bpf_map_alloc_percpu(const struct bpf_map *map, size_t size,
437 				    size_t align, gfp_t flags)
438 {
439 	struct mem_cgroup *old_memcg;
440 	void __percpu *ptr;
441 
442 	old_memcg = set_active_memcg(map->memcg);
443 	ptr = __alloc_percpu_gfp(size, align, flags | __GFP_ACCOUNT);
444 	set_active_memcg(old_memcg);
445 
446 	return ptr;
447 }
448 
449 #else
450 static void bpf_map_save_memcg(struct bpf_map *map)
451 {
452 }
453 
454 static void bpf_map_release_memcg(struct bpf_map *map)
455 {
456 }
457 #endif
458 
459 /* called from workqueue */
460 static void bpf_map_free_deferred(struct work_struct *work)
461 {
462 	struct bpf_map *map = container_of(work, struct bpf_map, work);
463 
464 	security_bpf_map_free(map);
465 	bpf_map_release_memcg(map);
466 	/* implementation dependent freeing */
467 	map->ops->map_free(map);
468 }
469 
470 static void bpf_map_put_uref(struct bpf_map *map)
471 {
472 	if (atomic64_dec_and_test(&map->usercnt)) {
473 		if (map->ops->map_release_uref)
474 			map->ops->map_release_uref(map);
475 	}
476 }
477 
478 /* decrement map refcnt and schedule it for freeing via workqueue
479  * (unrelying map implementation ops->map_free() might sleep)
480  */
481 static void __bpf_map_put(struct bpf_map *map, bool do_idr_lock)
482 {
483 	if (atomic64_dec_and_test(&map->refcnt)) {
484 		/* bpf_map_free_id() must be called first */
485 		bpf_map_free_id(map, do_idr_lock);
486 		btf_put(map->btf);
487 		INIT_WORK(&map->work, bpf_map_free_deferred);
488 		schedule_work(&map->work);
489 	}
490 }
491 
492 void bpf_map_put(struct bpf_map *map)
493 {
494 	__bpf_map_put(map, true);
495 }
496 EXPORT_SYMBOL_GPL(bpf_map_put);
497 
498 void bpf_map_put_with_uref(struct bpf_map *map)
499 {
500 	bpf_map_put_uref(map);
501 	bpf_map_put(map);
502 }
503 
504 static int bpf_map_release(struct inode *inode, struct file *filp)
505 {
506 	struct bpf_map *map = filp->private_data;
507 
508 	if (map->ops->map_release)
509 		map->ops->map_release(map, filp);
510 
511 	bpf_map_put_with_uref(map);
512 	return 0;
513 }
514 
515 static fmode_t map_get_sys_perms(struct bpf_map *map, struct fd f)
516 {
517 	fmode_t mode = f.file->f_mode;
518 
519 	/* Our file permissions may have been overridden by global
520 	 * map permissions facing syscall side.
521 	 */
522 	if (READ_ONCE(map->frozen))
523 		mode &= ~FMODE_CAN_WRITE;
524 	return mode;
525 }
526 
527 #ifdef CONFIG_PROC_FS
528 /* Provides an approximation of the map's memory footprint.
529  * Used only to provide a backward compatibility and display
530  * a reasonable "memlock" info.
531  */
532 static unsigned long bpf_map_memory_footprint(const struct bpf_map *map)
533 {
534 	unsigned long size;
535 
536 	size = round_up(map->key_size + bpf_map_value_size(map), 8);
537 
538 	return round_up(map->max_entries * size, PAGE_SIZE);
539 }
540 
541 static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp)
542 {
543 	const struct bpf_map *map = filp->private_data;
544 	const struct bpf_array *array;
545 	u32 type = 0, jited = 0;
546 
547 	if (map->map_type == BPF_MAP_TYPE_PROG_ARRAY) {
548 		array = container_of(map, struct bpf_array, map);
549 		spin_lock(&array->aux->owner.lock);
550 		type  = array->aux->owner.type;
551 		jited = array->aux->owner.jited;
552 		spin_unlock(&array->aux->owner.lock);
553 	}
554 
555 	seq_printf(m,
556 		   "map_type:\t%u\n"
557 		   "key_size:\t%u\n"
558 		   "value_size:\t%u\n"
559 		   "max_entries:\t%u\n"
560 		   "map_flags:\t%#x\n"
561 		   "map_extra:\t%#llx\n"
562 		   "memlock:\t%lu\n"
563 		   "map_id:\t%u\n"
564 		   "frozen:\t%u\n",
565 		   map->map_type,
566 		   map->key_size,
567 		   map->value_size,
568 		   map->max_entries,
569 		   map->map_flags,
570 		   (unsigned long long)map->map_extra,
571 		   bpf_map_memory_footprint(map),
572 		   map->id,
573 		   READ_ONCE(map->frozen));
574 	if (type) {
575 		seq_printf(m, "owner_prog_type:\t%u\n", type);
576 		seq_printf(m, "owner_jited:\t%u\n", jited);
577 	}
578 }
579 #endif
580 
581 static ssize_t bpf_dummy_read(struct file *filp, char __user *buf, size_t siz,
582 			      loff_t *ppos)
583 {
584 	/* We need this handler such that alloc_file() enables
585 	 * f_mode with FMODE_CAN_READ.
586 	 */
587 	return -EINVAL;
588 }
589 
590 static ssize_t bpf_dummy_write(struct file *filp, const char __user *buf,
591 			       size_t siz, loff_t *ppos)
592 {
593 	/* We need this handler such that alloc_file() enables
594 	 * f_mode with FMODE_CAN_WRITE.
595 	 */
596 	return -EINVAL;
597 }
598 
599 /* called for any extra memory-mapped regions (except initial) */
600 static void bpf_map_mmap_open(struct vm_area_struct *vma)
601 {
602 	struct bpf_map *map = vma->vm_file->private_data;
603 
604 	if (vma->vm_flags & VM_MAYWRITE) {
605 		mutex_lock(&map->freeze_mutex);
606 		map->writecnt++;
607 		mutex_unlock(&map->freeze_mutex);
608 	}
609 }
610 
611 /* called for all unmapped memory region (including initial) */
612 static void bpf_map_mmap_close(struct vm_area_struct *vma)
613 {
614 	struct bpf_map *map = vma->vm_file->private_data;
615 
616 	if (vma->vm_flags & VM_MAYWRITE) {
617 		mutex_lock(&map->freeze_mutex);
618 		map->writecnt--;
619 		mutex_unlock(&map->freeze_mutex);
620 	}
621 }
622 
623 static const struct vm_operations_struct bpf_map_default_vmops = {
624 	.open		= bpf_map_mmap_open,
625 	.close		= bpf_map_mmap_close,
626 };
627 
628 static int bpf_map_mmap(struct file *filp, struct vm_area_struct *vma)
629 {
630 	struct bpf_map *map = filp->private_data;
631 	int err;
632 
633 	if (!map->ops->map_mmap || map_value_has_spin_lock(map) ||
634 	    map_value_has_timer(map))
635 		return -ENOTSUPP;
636 
637 	if (!(vma->vm_flags & VM_SHARED))
638 		return -EINVAL;
639 
640 	mutex_lock(&map->freeze_mutex);
641 
642 	if (vma->vm_flags & VM_WRITE) {
643 		if (map->frozen) {
644 			err = -EPERM;
645 			goto out;
646 		}
647 		/* map is meant to be read-only, so do not allow mapping as
648 		 * writable, because it's possible to leak a writable page
649 		 * reference and allows user-space to still modify it after
650 		 * freezing, while verifier will assume contents do not change
651 		 */
652 		if (map->map_flags & BPF_F_RDONLY_PROG) {
653 			err = -EACCES;
654 			goto out;
655 		}
656 	}
657 
658 	/* set default open/close callbacks */
659 	vma->vm_ops = &bpf_map_default_vmops;
660 	vma->vm_private_data = map;
661 	vma->vm_flags &= ~VM_MAYEXEC;
662 	if (!(vma->vm_flags & VM_WRITE))
663 		/* disallow re-mapping with PROT_WRITE */
664 		vma->vm_flags &= ~VM_MAYWRITE;
665 
666 	err = map->ops->map_mmap(map, vma);
667 	if (err)
668 		goto out;
669 
670 	if (vma->vm_flags & VM_MAYWRITE)
671 		map->writecnt++;
672 out:
673 	mutex_unlock(&map->freeze_mutex);
674 	return err;
675 }
676 
677 static __poll_t bpf_map_poll(struct file *filp, struct poll_table_struct *pts)
678 {
679 	struct bpf_map *map = filp->private_data;
680 
681 	if (map->ops->map_poll)
682 		return map->ops->map_poll(map, filp, pts);
683 
684 	return EPOLLERR;
685 }
686 
687 const struct file_operations bpf_map_fops = {
688 #ifdef CONFIG_PROC_FS
689 	.show_fdinfo	= bpf_map_show_fdinfo,
690 #endif
691 	.release	= bpf_map_release,
692 	.read		= bpf_dummy_read,
693 	.write		= bpf_dummy_write,
694 	.mmap		= bpf_map_mmap,
695 	.poll		= bpf_map_poll,
696 };
697 
698 int bpf_map_new_fd(struct bpf_map *map, int flags)
699 {
700 	int ret;
701 
702 	ret = security_bpf_map(map, OPEN_FMODE(flags));
703 	if (ret < 0)
704 		return ret;
705 
706 	return anon_inode_getfd("bpf-map", &bpf_map_fops, map,
707 				flags | O_CLOEXEC);
708 }
709 
710 int bpf_get_file_flag(int flags)
711 {
712 	if ((flags & BPF_F_RDONLY) && (flags & BPF_F_WRONLY))
713 		return -EINVAL;
714 	if (flags & BPF_F_RDONLY)
715 		return O_RDONLY;
716 	if (flags & BPF_F_WRONLY)
717 		return O_WRONLY;
718 	return O_RDWR;
719 }
720 
721 /* helper macro to check that unused fields 'union bpf_attr' are zero */
722 #define CHECK_ATTR(CMD) \
723 	memchr_inv((void *) &attr->CMD##_LAST_FIELD + \
724 		   sizeof(attr->CMD##_LAST_FIELD), 0, \
725 		   sizeof(*attr) - \
726 		   offsetof(union bpf_attr, CMD##_LAST_FIELD) - \
727 		   sizeof(attr->CMD##_LAST_FIELD)) != NULL
728 
729 /* dst and src must have at least "size" number of bytes.
730  * Return strlen on success and < 0 on error.
731  */
732 int bpf_obj_name_cpy(char *dst, const char *src, unsigned int size)
733 {
734 	const char *end = src + size;
735 	const char *orig_src = src;
736 
737 	memset(dst, 0, size);
738 	/* Copy all isalnum(), '_' and '.' chars. */
739 	while (src < end && *src) {
740 		if (!isalnum(*src) &&
741 		    *src != '_' && *src != '.')
742 			return -EINVAL;
743 		*dst++ = *src++;
744 	}
745 
746 	/* No '\0' found in "size" number of bytes */
747 	if (src == end)
748 		return -EINVAL;
749 
750 	return src - orig_src;
751 }
752 
753 int map_check_no_btf(const struct bpf_map *map,
754 		     const struct btf *btf,
755 		     const struct btf_type *key_type,
756 		     const struct btf_type *value_type)
757 {
758 	return -ENOTSUPP;
759 }
760 
761 static int map_check_btf(struct bpf_map *map, const struct btf *btf,
762 			 u32 btf_key_id, u32 btf_value_id)
763 {
764 	const struct btf_type *key_type, *value_type;
765 	u32 key_size, value_size;
766 	int ret = 0;
767 
768 	/* Some maps allow key to be unspecified. */
769 	if (btf_key_id) {
770 		key_type = btf_type_id_size(btf, &btf_key_id, &key_size);
771 		if (!key_type || key_size != map->key_size)
772 			return -EINVAL;
773 	} else {
774 		key_type = btf_type_by_id(btf, 0);
775 		if (!map->ops->map_check_btf)
776 			return -EINVAL;
777 	}
778 
779 	value_type = btf_type_id_size(btf, &btf_value_id, &value_size);
780 	if (!value_type || value_size != map->value_size)
781 		return -EINVAL;
782 
783 	map->spin_lock_off = btf_find_spin_lock(btf, value_type);
784 
785 	if (map_value_has_spin_lock(map)) {
786 		if (map->map_flags & BPF_F_RDONLY_PROG)
787 			return -EACCES;
788 		if (map->map_type != BPF_MAP_TYPE_HASH &&
789 		    map->map_type != BPF_MAP_TYPE_ARRAY &&
790 		    map->map_type != BPF_MAP_TYPE_CGROUP_STORAGE &&
791 		    map->map_type != BPF_MAP_TYPE_SK_STORAGE &&
792 		    map->map_type != BPF_MAP_TYPE_INODE_STORAGE &&
793 		    map->map_type != BPF_MAP_TYPE_TASK_STORAGE)
794 			return -ENOTSUPP;
795 		if (map->spin_lock_off + sizeof(struct bpf_spin_lock) >
796 		    map->value_size) {
797 			WARN_ONCE(1,
798 				  "verifier bug spin_lock_off %d value_size %d\n",
799 				  map->spin_lock_off, map->value_size);
800 			return -EFAULT;
801 		}
802 	}
803 
804 	map->timer_off = btf_find_timer(btf, value_type);
805 	if (map_value_has_timer(map)) {
806 		if (map->map_flags & BPF_F_RDONLY_PROG)
807 			return -EACCES;
808 		if (map->map_type != BPF_MAP_TYPE_HASH &&
809 		    map->map_type != BPF_MAP_TYPE_LRU_HASH &&
810 		    map->map_type != BPF_MAP_TYPE_ARRAY)
811 			return -EOPNOTSUPP;
812 	}
813 
814 	if (map->ops->map_check_btf)
815 		ret = map->ops->map_check_btf(map, btf, key_type, value_type);
816 
817 	return ret;
818 }
819 
820 #define BPF_MAP_CREATE_LAST_FIELD map_extra
821 /* called via syscall */
822 static int map_create(union bpf_attr *attr)
823 {
824 	int numa_node = bpf_map_attr_numa_node(attr);
825 	struct bpf_map *map;
826 	int f_flags;
827 	int err;
828 
829 	err = CHECK_ATTR(BPF_MAP_CREATE);
830 	if (err)
831 		return -EINVAL;
832 
833 	if (attr->btf_vmlinux_value_type_id) {
834 		if (attr->map_type != BPF_MAP_TYPE_STRUCT_OPS ||
835 		    attr->btf_key_type_id || attr->btf_value_type_id)
836 			return -EINVAL;
837 	} else if (attr->btf_key_type_id && !attr->btf_value_type_id) {
838 		return -EINVAL;
839 	}
840 
841 	if (attr->map_type != BPF_MAP_TYPE_BLOOM_FILTER &&
842 	    attr->map_extra != 0)
843 		return -EINVAL;
844 
845 	f_flags = bpf_get_file_flag(attr->map_flags);
846 	if (f_flags < 0)
847 		return f_flags;
848 
849 	if (numa_node != NUMA_NO_NODE &&
850 	    ((unsigned int)numa_node >= nr_node_ids ||
851 	     !node_online(numa_node)))
852 		return -EINVAL;
853 
854 	/* find map type and init map: hashtable vs rbtree vs bloom vs ... */
855 	map = find_and_alloc_map(attr);
856 	if (IS_ERR(map))
857 		return PTR_ERR(map);
858 
859 	err = bpf_obj_name_cpy(map->name, attr->map_name,
860 			       sizeof(attr->map_name));
861 	if (err < 0)
862 		goto free_map;
863 
864 	atomic64_set(&map->refcnt, 1);
865 	atomic64_set(&map->usercnt, 1);
866 	mutex_init(&map->freeze_mutex);
867 
868 	map->spin_lock_off = -EINVAL;
869 	map->timer_off = -EINVAL;
870 	if (attr->btf_key_type_id || attr->btf_value_type_id ||
871 	    /* Even the map's value is a kernel's struct,
872 	     * the bpf_prog.o must have BTF to begin with
873 	     * to figure out the corresponding kernel's
874 	     * counter part.  Thus, attr->btf_fd has
875 	     * to be valid also.
876 	     */
877 	    attr->btf_vmlinux_value_type_id) {
878 		struct btf *btf;
879 
880 		btf = btf_get_by_fd(attr->btf_fd);
881 		if (IS_ERR(btf)) {
882 			err = PTR_ERR(btf);
883 			goto free_map;
884 		}
885 		if (btf_is_kernel(btf)) {
886 			btf_put(btf);
887 			err = -EACCES;
888 			goto free_map;
889 		}
890 		map->btf = btf;
891 
892 		if (attr->btf_value_type_id) {
893 			err = map_check_btf(map, btf, attr->btf_key_type_id,
894 					    attr->btf_value_type_id);
895 			if (err)
896 				goto free_map;
897 		}
898 
899 		map->btf_key_type_id = attr->btf_key_type_id;
900 		map->btf_value_type_id = attr->btf_value_type_id;
901 		map->btf_vmlinux_value_type_id =
902 			attr->btf_vmlinux_value_type_id;
903 	}
904 
905 	err = security_bpf_map_alloc(map);
906 	if (err)
907 		goto free_map;
908 
909 	err = bpf_map_alloc_id(map);
910 	if (err)
911 		goto free_map_sec;
912 
913 	bpf_map_save_memcg(map);
914 
915 	err = bpf_map_new_fd(map, f_flags);
916 	if (err < 0) {
917 		/* failed to allocate fd.
918 		 * bpf_map_put_with_uref() is needed because the above
919 		 * bpf_map_alloc_id() has published the map
920 		 * to the userspace and the userspace may
921 		 * have refcnt-ed it through BPF_MAP_GET_FD_BY_ID.
922 		 */
923 		bpf_map_put_with_uref(map);
924 		return err;
925 	}
926 
927 	return err;
928 
929 free_map_sec:
930 	security_bpf_map_free(map);
931 free_map:
932 	btf_put(map->btf);
933 	map->ops->map_free(map);
934 	return err;
935 }
936 
937 /* if error is returned, fd is released.
938  * On success caller should complete fd access with matching fdput()
939  */
940 struct bpf_map *__bpf_map_get(struct fd f)
941 {
942 	if (!f.file)
943 		return ERR_PTR(-EBADF);
944 	if (f.file->f_op != &bpf_map_fops) {
945 		fdput(f);
946 		return ERR_PTR(-EINVAL);
947 	}
948 
949 	return f.file->private_data;
950 }
951 
952 void bpf_map_inc(struct bpf_map *map)
953 {
954 	atomic64_inc(&map->refcnt);
955 }
956 EXPORT_SYMBOL_GPL(bpf_map_inc);
957 
958 void bpf_map_inc_with_uref(struct bpf_map *map)
959 {
960 	atomic64_inc(&map->refcnt);
961 	atomic64_inc(&map->usercnt);
962 }
963 EXPORT_SYMBOL_GPL(bpf_map_inc_with_uref);
964 
965 struct bpf_map *bpf_map_get(u32 ufd)
966 {
967 	struct fd f = fdget(ufd);
968 	struct bpf_map *map;
969 
970 	map = __bpf_map_get(f);
971 	if (IS_ERR(map))
972 		return map;
973 
974 	bpf_map_inc(map);
975 	fdput(f);
976 
977 	return map;
978 }
979 
980 struct bpf_map *bpf_map_get_with_uref(u32 ufd)
981 {
982 	struct fd f = fdget(ufd);
983 	struct bpf_map *map;
984 
985 	map = __bpf_map_get(f);
986 	if (IS_ERR(map))
987 		return map;
988 
989 	bpf_map_inc_with_uref(map);
990 	fdput(f);
991 
992 	return map;
993 }
994 
995 /* map_idr_lock should have been held */
996 static struct bpf_map *__bpf_map_inc_not_zero(struct bpf_map *map, bool uref)
997 {
998 	int refold;
999 
1000 	refold = atomic64_fetch_add_unless(&map->refcnt, 1, 0);
1001 	if (!refold)
1002 		return ERR_PTR(-ENOENT);
1003 	if (uref)
1004 		atomic64_inc(&map->usercnt);
1005 
1006 	return map;
1007 }
1008 
1009 struct bpf_map *bpf_map_inc_not_zero(struct bpf_map *map)
1010 {
1011 	spin_lock_bh(&map_idr_lock);
1012 	map = __bpf_map_inc_not_zero(map, false);
1013 	spin_unlock_bh(&map_idr_lock);
1014 
1015 	return map;
1016 }
1017 EXPORT_SYMBOL_GPL(bpf_map_inc_not_zero);
1018 
1019 int __weak bpf_stackmap_copy(struct bpf_map *map, void *key, void *value)
1020 {
1021 	return -ENOTSUPP;
1022 }
1023 
1024 static void *__bpf_copy_key(void __user *ukey, u64 key_size)
1025 {
1026 	if (key_size)
1027 		return vmemdup_user(ukey, key_size);
1028 
1029 	if (ukey)
1030 		return ERR_PTR(-EINVAL);
1031 
1032 	return NULL;
1033 }
1034 
1035 static void *___bpf_copy_key(bpfptr_t ukey, u64 key_size)
1036 {
1037 	if (key_size)
1038 		return kvmemdup_bpfptr(ukey, key_size);
1039 
1040 	if (!bpfptr_is_null(ukey))
1041 		return ERR_PTR(-EINVAL);
1042 
1043 	return NULL;
1044 }
1045 
1046 /* last field in 'union bpf_attr' used by this command */
1047 #define BPF_MAP_LOOKUP_ELEM_LAST_FIELD flags
1048 
1049 static int map_lookup_elem(union bpf_attr *attr)
1050 {
1051 	void __user *ukey = u64_to_user_ptr(attr->key);
1052 	void __user *uvalue = u64_to_user_ptr(attr->value);
1053 	int ufd = attr->map_fd;
1054 	struct bpf_map *map;
1055 	void *key, *value;
1056 	u32 value_size;
1057 	struct fd f;
1058 	int err;
1059 
1060 	if (CHECK_ATTR(BPF_MAP_LOOKUP_ELEM))
1061 		return -EINVAL;
1062 
1063 	if (attr->flags & ~BPF_F_LOCK)
1064 		return -EINVAL;
1065 
1066 	f = fdget(ufd);
1067 	map = __bpf_map_get(f);
1068 	if (IS_ERR(map))
1069 		return PTR_ERR(map);
1070 	if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) {
1071 		err = -EPERM;
1072 		goto err_put;
1073 	}
1074 
1075 	if ((attr->flags & BPF_F_LOCK) &&
1076 	    !map_value_has_spin_lock(map)) {
1077 		err = -EINVAL;
1078 		goto err_put;
1079 	}
1080 
1081 	key = __bpf_copy_key(ukey, map->key_size);
1082 	if (IS_ERR(key)) {
1083 		err = PTR_ERR(key);
1084 		goto err_put;
1085 	}
1086 
1087 	value_size = bpf_map_value_size(map);
1088 
1089 	err = -ENOMEM;
1090 	value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN);
1091 	if (!value)
1092 		goto free_key;
1093 
1094 	if (map->map_type == BPF_MAP_TYPE_BLOOM_FILTER) {
1095 		if (copy_from_user(value, uvalue, value_size))
1096 			err = -EFAULT;
1097 		else
1098 			err = bpf_map_copy_value(map, key, value, attr->flags);
1099 		goto free_value;
1100 	}
1101 
1102 	err = bpf_map_copy_value(map, key, value, attr->flags);
1103 	if (err)
1104 		goto free_value;
1105 
1106 	err = -EFAULT;
1107 	if (copy_to_user(uvalue, value, value_size) != 0)
1108 		goto free_value;
1109 
1110 	err = 0;
1111 
1112 free_value:
1113 	kvfree(value);
1114 free_key:
1115 	kvfree(key);
1116 err_put:
1117 	fdput(f);
1118 	return err;
1119 }
1120 
1121 
1122 #define BPF_MAP_UPDATE_ELEM_LAST_FIELD flags
1123 
1124 static int map_update_elem(union bpf_attr *attr, bpfptr_t uattr)
1125 {
1126 	bpfptr_t ukey = make_bpfptr(attr->key, uattr.is_kernel);
1127 	bpfptr_t uvalue = make_bpfptr(attr->value, uattr.is_kernel);
1128 	int ufd = attr->map_fd;
1129 	struct bpf_map *map;
1130 	void *key, *value;
1131 	u32 value_size;
1132 	struct fd f;
1133 	int err;
1134 
1135 	if (CHECK_ATTR(BPF_MAP_UPDATE_ELEM))
1136 		return -EINVAL;
1137 
1138 	f = fdget(ufd);
1139 	map = __bpf_map_get(f);
1140 	if (IS_ERR(map))
1141 		return PTR_ERR(map);
1142 	if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
1143 		err = -EPERM;
1144 		goto err_put;
1145 	}
1146 
1147 	if ((attr->flags & BPF_F_LOCK) &&
1148 	    !map_value_has_spin_lock(map)) {
1149 		err = -EINVAL;
1150 		goto err_put;
1151 	}
1152 
1153 	key = ___bpf_copy_key(ukey, map->key_size);
1154 	if (IS_ERR(key)) {
1155 		err = PTR_ERR(key);
1156 		goto err_put;
1157 	}
1158 
1159 	value_size = bpf_map_value_size(map);
1160 
1161 	err = -ENOMEM;
1162 	value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN);
1163 	if (!value)
1164 		goto free_key;
1165 
1166 	err = -EFAULT;
1167 	if (copy_from_bpfptr(value, uvalue, value_size) != 0)
1168 		goto free_value;
1169 
1170 	err = bpf_map_update_value(map, f, key, value, attr->flags);
1171 
1172 free_value:
1173 	kvfree(value);
1174 free_key:
1175 	kvfree(key);
1176 err_put:
1177 	fdput(f);
1178 	return err;
1179 }
1180 
1181 #define BPF_MAP_DELETE_ELEM_LAST_FIELD key
1182 
1183 static int map_delete_elem(union bpf_attr *attr)
1184 {
1185 	void __user *ukey = u64_to_user_ptr(attr->key);
1186 	int ufd = attr->map_fd;
1187 	struct bpf_map *map;
1188 	struct fd f;
1189 	void *key;
1190 	int err;
1191 
1192 	if (CHECK_ATTR(BPF_MAP_DELETE_ELEM))
1193 		return -EINVAL;
1194 
1195 	f = fdget(ufd);
1196 	map = __bpf_map_get(f);
1197 	if (IS_ERR(map))
1198 		return PTR_ERR(map);
1199 	if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
1200 		err = -EPERM;
1201 		goto err_put;
1202 	}
1203 
1204 	key = __bpf_copy_key(ukey, map->key_size);
1205 	if (IS_ERR(key)) {
1206 		err = PTR_ERR(key);
1207 		goto err_put;
1208 	}
1209 
1210 	if (bpf_map_is_dev_bound(map)) {
1211 		err = bpf_map_offload_delete_elem(map, key);
1212 		goto out;
1213 	} else if (IS_FD_PROG_ARRAY(map) ||
1214 		   map->map_type == BPF_MAP_TYPE_STRUCT_OPS) {
1215 		/* These maps require sleepable context */
1216 		err = map->ops->map_delete_elem(map, key);
1217 		goto out;
1218 	}
1219 
1220 	bpf_disable_instrumentation();
1221 	rcu_read_lock();
1222 	err = map->ops->map_delete_elem(map, key);
1223 	rcu_read_unlock();
1224 	bpf_enable_instrumentation();
1225 	maybe_wait_bpf_programs(map);
1226 out:
1227 	kvfree(key);
1228 err_put:
1229 	fdput(f);
1230 	return err;
1231 }
1232 
1233 /* last field in 'union bpf_attr' used by this command */
1234 #define BPF_MAP_GET_NEXT_KEY_LAST_FIELD next_key
1235 
1236 static int map_get_next_key(union bpf_attr *attr)
1237 {
1238 	void __user *ukey = u64_to_user_ptr(attr->key);
1239 	void __user *unext_key = u64_to_user_ptr(attr->next_key);
1240 	int ufd = attr->map_fd;
1241 	struct bpf_map *map;
1242 	void *key, *next_key;
1243 	struct fd f;
1244 	int err;
1245 
1246 	if (CHECK_ATTR(BPF_MAP_GET_NEXT_KEY))
1247 		return -EINVAL;
1248 
1249 	f = fdget(ufd);
1250 	map = __bpf_map_get(f);
1251 	if (IS_ERR(map))
1252 		return PTR_ERR(map);
1253 	if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) {
1254 		err = -EPERM;
1255 		goto err_put;
1256 	}
1257 
1258 	if (ukey) {
1259 		key = __bpf_copy_key(ukey, map->key_size);
1260 		if (IS_ERR(key)) {
1261 			err = PTR_ERR(key);
1262 			goto err_put;
1263 		}
1264 	} else {
1265 		key = NULL;
1266 	}
1267 
1268 	err = -ENOMEM;
1269 	next_key = kvmalloc(map->key_size, GFP_USER);
1270 	if (!next_key)
1271 		goto free_key;
1272 
1273 	if (bpf_map_is_dev_bound(map)) {
1274 		err = bpf_map_offload_get_next_key(map, key, next_key);
1275 		goto out;
1276 	}
1277 
1278 	rcu_read_lock();
1279 	err = map->ops->map_get_next_key(map, key, next_key);
1280 	rcu_read_unlock();
1281 out:
1282 	if (err)
1283 		goto free_next_key;
1284 
1285 	err = -EFAULT;
1286 	if (copy_to_user(unext_key, next_key, map->key_size) != 0)
1287 		goto free_next_key;
1288 
1289 	err = 0;
1290 
1291 free_next_key:
1292 	kvfree(next_key);
1293 free_key:
1294 	kvfree(key);
1295 err_put:
1296 	fdput(f);
1297 	return err;
1298 }
1299 
1300 int generic_map_delete_batch(struct bpf_map *map,
1301 			     const union bpf_attr *attr,
1302 			     union bpf_attr __user *uattr)
1303 {
1304 	void __user *keys = u64_to_user_ptr(attr->batch.keys);
1305 	u32 cp, max_count;
1306 	int err = 0;
1307 	void *key;
1308 
1309 	if (attr->batch.elem_flags & ~BPF_F_LOCK)
1310 		return -EINVAL;
1311 
1312 	if ((attr->batch.elem_flags & BPF_F_LOCK) &&
1313 	    !map_value_has_spin_lock(map)) {
1314 		return -EINVAL;
1315 	}
1316 
1317 	max_count = attr->batch.count;
1318 	if (!max_count)
1319 		return 0;
1320 
1321 	key = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN);
1322 	if (!key)
1323 		return -ENOMEM;
1324 
1325 	for (cp = 0; cp < max_count; cp++) {
1326 		err = -EFAULT;
1327 		if (copy_from_user(key, keys + cp * map->key_size,
1328 				   map->key_size))
1329 			break;
1330 
1331 		if (bpf_map_is_dev_bound(map)) {
1332 			err = bpf_map_offload_delete_elem(map, key);
1333 			break;
1334 		}
1335 
1336 		bpf_disable_instrumentation();
1337 		rcu_read_lock();
1338 		err = map->ops->map_delete_elem(map, key);
1339 		rcu_read_unlock();
1340 		bpf_enable_instrumentation();
1341 		maybe_wait_bpf_programs(map);
1342 		if (err)
1343 			break;
1344 	}
1345 	if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp)))
1346 		err = -EFAULT;
1347 
1348 	kvfree(key);
1349 	return err;
1350 }
1351 
1352 int generic_map_update_batch(struct bpf_map *map,
1353 			     const union bpf_attr *attr,
1354 			     union bpf_attr __user *uattr)
1355 {
1356 	void __user *values = u64_to_user_ptr(attr->batch.values);
1357 	void __user *keys = u64_to_user_ptr(attr->batch.keys);
1358 	u32 value_size, cp, max_count;
1359 	int ufd = attr->batch.map_fd;
1360 	void *key, *value;
1361 	struct fd f;
1362 	int err = 0;
1363 
1364 	if (attr->batch.elem_flags & ~BPF_F_LOCK)
1365 		return -EINVAL;
1366 
1367 	if ((attr->batch.elem_flags & BPF_F_LOCK) &&
1368 	    !map_value_has_spin_lock(map)) {
1369 		return -EINVAL;
1370 	}
1371 
1372 	value_size = bpf_map_value_size(map);
1373 
1374 	max_count = attr->batch.count;
1375 	if (!max_count)
1376 		return 0;
1377 
1378 	key = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN);
1379 	if (!key)
1380 		return -ENOMEM;
1381 
1382 	value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN);
1383 	if (!value) {
1384 		kvfree(key);
1385 		return -ENOMEM;
1386 	}
1387 
1388 	f = fdget(ufd); /* bpf_map_do_batch() guarantees ufd is valid */
1389 	for (cp = 0; cp < max_count; cp++) {
1390 		err = -EFAULT;
1391 		if (copy_from_user(key, keys + cp * map->key_size,
1392 		    map->key_size) ||
1393 		    copy_from_user(value, values + cp * value_size, value_size))
1394 			break;
1395 
1396 		err = bpf_map_update_value(map, f, key, value,
1397 					   attr->batch.elem_flags);
1398 
1399 		if (err)
1400 			break;
1401 	}
1402 
1403 	if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp)))
1404 		err = -EFAULT;
1405 
1406 	kvfree(value);
1407 	kvfree(key);
1408 	fdput(f);
1409 	return err;
1410 }
1411 
1412 #define MAP_LOOKUP_RETRIES 3
1413 
1414 int generic_map_lookup_batch(struct bpf_map *map,
1415 				    const union bpf_attr *attr,
1416 				    union bpf_attr __user *uattr)
1417 {
1418 	void __user *uobatch = u64_to_user_ptr(attr->batch.out_batch);
1419 	void __user *ubatch = u64_to_user_ptr(attr->batch.in_batch);
1420 	void __user *values = u64_to_user_ptr(attr->batch.values);
1421 	void __user *keys = u64_to_user_ptr(attr->batch.keys);
1422 	void *buf, *buf_prevkey, *prev_key, *key, *value;
1423 	int err, retry = MAP_LOOKUP_RETRIES;
1424 	u32 value_size, cp, max_count;
1425 
1426 	if (attr->batch.elem_flags & ~BPF_F_LOCK)
1427 		return -EINVAL;
1428 
1429 	if ((attr->batch.elem_flags & BPF_F_LOCK) &&
1430 	    !map_value_has_spin_lock(map))
1431 		return -EINVAL;
1432 
1433 	value_size = bpf_map_value_size(map);
1434 
1435 	max_count = attr->batch.count;
1436 	if (!max_count)
1437 		return 0;
1438 
1439 	if (put_user(0, &uattr->batch.count))
1440 		return -EFAULT;
1441 
1442 	buf_prevkey = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN);
1443 	if (!buf_prevkey)
1444 		return -ENOMEM;
1445 
1446 	buf = kvmalloc(map->key_size + value_size, GFP_USER | __GFP_NOWARN);
1447 	if (!buf) {
1448 		kvfree(buf_prevkey);
1449 		return -ENOMEM;
1450 	}
1451 
1452 	err = -EFAULT;
1453 	prev_key = NULL;
1454 	if (ubatch && copy_from_user(buf_prevkey, ubatch, map->key_size))
1455 		goto free_buf;
1456 	key = buf;
1457 	value = key + map->key_size;
1458 	if (ubatch)
1459 		prev_key = buf_prevkey;
1460 
1461 	for (cp = 0; cp < max_count;) {
1462 		rcu_read_lock();
1463 		err = map->ops->map_get_next_key(map, prev_key, key);
1464 		rcu_read_unlock();
1465 		if (err)
1466 			break;
1467 		err = bpf_map_copy_value(map, key, value,
1468 					 attr->batch.elem_flags);
1469 
1470 		if (err == -ENOENT) {
1471 			if (retry) {
1472 				retry--;
1473 				continue;
1474 			}
1475 			err = -EINTR;
1476 			break;
1477 		}
1478 
1479 		if (err)
1480 			goto free_buf;
1481 
1482 		if (copy_to_user(keys + cp * map->key_size, key,
1483 				 map->key_size)) {
1484 			err = -EFAULT;
1485 			goto free_buf;
1486 		}
1487 		if (copy_to_user(values + cp * value_size, value, value_size)) {
1488 			err = -EFAULT;
1489 			goto free_buf;
1490 		}
1491 
1492 		if (!prev_key)
1493 			prev_key = buf_prevkey;
1494 
1495 		swap(prev_key, key);
1496 		retry = MAP_LOOKUP_RETRIES;
1497 		cp++;
1498 	}
1499 
1500 	if (err == -EFAULT)
1501 		goto free_buf;
1502 
1503 	if ((copy_to_user(&uattr->batch.count, &cp, sizeof(cp)) ||
1504 		    (cp && copy_to_user(uobatch, prev_key, map->key_size))))
1505 		err = -EFAULT;
1506 
1507 free_buf:
1508 	kvfree(buf_prevkey);
1509 	kvfree(buf);
1510 	return err;
1511 }
1512 
1513 #define BPF_MAP_LOOKUP_AND_DELETE_ELEM_LAST_FIELD flags
1514 
1515 static int map_lookup_and_delete_elem(union bpf_attr *attr)
1516 {
1517 	void __user *ukey = u64_to_user_ptr(attr->key);
1518 	void __user *uvalue = u64_to_user_ptr(attr->value);
1519 	int ufd = attr->map_fd;
1520 	struct bpf_map *map;
1521 	void *key, *value;
1522 	u32 value_size;
1523 	struct fd f;
1524 	int err;
1525 
1526 	if (CHECK_ATTR(BPF_MAP_LOOKUP_AND_DELETE_ELEM))
1527 		return -EINVAL;
1528 
1529 	if (attr->flags & ~BPF_F_LOCK)
1530 		return -EINVAL;
1531 
1532 	f = fdget(ufd);
1533 	map = __bpf_map_get(f);
1534 	if (IS_ERR(map))
1535 		return PTR_ERR(map);
1536 	if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ) ||
1537 	    !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
1538 		err = -EPERM;
1539 		goto err_put;
1540 	}
1541 
1542 	if (attr->flags &&
1543 	    (map->map_type == BPF_MAP_TYPE_QUEUE ||
1544 	     map->map_type == BPF_MAP_TYPE_STACK)) {
1545 		err = -EINVAL;
1546 		goto err_put;
1547 	}
1548 
1549 	if ((attr->flags & BPF_F_LOCK) &&
1550 	    !map_value_has_spin_lock(map)) {
1551 		err = -EINVAL;
1552 		goto err_put;
1553 	}
1554 
1555 	key = __bpf_copy_key(ukey, map->key_size);
1556 	if (IS_ERR(key)) {
1557 		err = PTR_ERR(key);
1558 		goto err_put;
1559 	}
1560 
1561 	value_size = bpf_map_value_size(map);
1562 
1563 	err = -ENOMEM;
1564 	value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN);
1565 	if (!value)
1566 		goto free_key;
1567 
1568 	err = -ENOTSUPP;
1569 	if (map->map_type == BPF_MAP_TYPE_QUEUE ||
1570 	    map->map_type == BPF_MAP_TYPE_STACK) {
1571 		err = map->ops->map_pop_elem(map, value);
1572 	} else if (map->map_type == BPF_MAP_TYPE_HASH ||
1573 		   map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
1574 		   map->map_type == BPF_MAP_TYPE_LRU_HASH ||
1575 		   map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
1576 		if (!bpf_map_is_dev_bound(map)) {
1577 			bpf_disable_instrumentation();
1578 			rcu_read_lock();
1579 			err = map->ops->map_lookup_and_delete_elem(map, key, value, attr->flags);
1580 			rcu_read_unlock();
1581 			bpf_enable_instrumentation();
1582 		}
1583 	}
1584 
1585 	if (err)
1586 		goto free_value;
1587 
1588 	if (copy_to_user(uvalue, value, value_size) != 0) {
1589 		err = -EFAULT;
1590 		goto free_value;
1591 	}
1592 
1593 	err = 0;
1594 
1595 free_value:
1596 	kvfree(value);
1597 free_key:
1598 	kvfree(key);
1599 err_put:
1600 	fdput(f);
1601 	return err;
1602 }
1603 
1604 #define BPF_MAP_FREEZE_LAST_FIELD map_fd
1605 
1606 static int map_freeze(const union bpf_attr *attr)
1607 {
1608 	int err = 0, ufd = attr->map_fd;
1609 	struct bpf_map *map;
1610 	struct fd f;
1611 
1612 	if (CHECK_ATTR(BPF_MAP_FREEZE))
1613 		return -EINVAL;
1614 
1615 	f = fdget(ufd);
1616 	map = __bpf_map_get(f);
1617 	if (IS_ERR(map))
1618 		return PTR_ERR(map);
1619 
1620 	if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS ||
1621 	    map_value_has_timer(map)) {
1622 		fdput(f);
1623 		return -ENOTSUPP;
1624 	}
1625 
1626 	mutex_lock(&map->freeze_mutex);
1627 
1628 	if (map->writecnt) {
1629 		err = -EBUSY;
1630 		goto err_put;
1631 	}
1632 	if (READ_ONCE(map->frozen)) {
1633 		err = -EBUSY;
1634 		goto err_put;
1635 	}
1636 	if (!bpf_capable()) {
1637 		err = -EPERM;
1638 		goto err_put;
1639 	}
1640 
1641 	WRITE_ONCE(map->frozen, true);
1642 err_put:
1643 	mutex_unlock(&map->freeze_mutex);
1644 	fdput(f);
1645 	return err;
1646 }
1647 
1648 static const struct bpf_prog_ops * const bpf_prog_types[] = {
1649 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) \
1650 	[_id] = & _name ## _prog_ops,
1651 #define BPF_MAP_TYPE(_id, _ops)
1652 #define BPF_LINK_TYPE(_id, _name)
1653 #include <linux/bpf_types.h>
1654 #undef BPF_PROG_TYPE
1655 #undef BPF_MAP_TYPE
1656 #undef BPF_LINK_TYPE
1657 };
1658 
1659 static int find_prog_type(enum bpf_prog_type type, struct bpf_prog *prog)
1660 {
1661 	const struct bpf_prog_ops *ops;
1662 
1663 	if (type >= ARRAY_SIZE(bpf_prog_types))
1664 		return -EINVAL;
1665 	type = array_index_nospec(type, ARRAY_SIZE(bpf_prog_types));
1666 	ops = bpf_prog_types[type];
1667 	if (!ops)
1668 		return -EINVAL;
1669 
1670 	if (!bpf_prog_is_dev_bound(prog->aux))
1671 		prog->aux->ops = ops;
1672 	else
1673 		prog->aux->ops = &bpf_offload_prog_ops;
1674 	prog->type = type;
1675 	return 0;
1676 }
1677 
1678 enum bpf_audit {
1679 	BPF_AUDIT_LOAD,
1680 	BPF_AUDIT_UNLOAD,
1681 	BPF_AUDIT_MAX,
1682 };
1683 
1684 static const char * const bpf_audit_str[BPF_AUDIT_MAX] = {
1685 	[BPF_AUDIT_LOAD]   = "LOAD",
1686 	[BPF_AUDIT_UNLOAD] = "UNLOAD",
1687 };
1688 
1689 static void bpf_audit_prog(const struct bpf_prog *prog, unsigned int op)
1690 {
1691 	struct audit_context *ctx = NULL;
1692 	struct audit_buffer *ab;
1693 
1694 	if (WARN_ON_ONCE(op >= BPF_AUDIT_MAX))
1695 		return;
1696 	if (audit_enabled == AUDIT_OFF)
1697 		return;
1698 	if (op == BPF_AUDIT_LOAD)
1699 		ctx = audit_context();
1700 	ab = audit_log_start(ctx, GFP_ATOMIC, AUDIT_BPF);
1701 	if (unlikely(!ab))
1702 		return;
1703 	audit_log_format(ab, "prog-id=%u op=%s",
1704 			 prog->aux->id, bpf_audit_str[op]);
1705 	audit_log_end(ab);
1706 }
1707 
1708 static int bpf_prog_alloc_id(struct bpf_prog *prog)
1709 {
1710 	int id;
1711 
1712 	idr_preload(GFP_KERNEL);
1713 	spin_lock_bh(&prog_idr_lock);
1714 	id = idr_alloc_cyclic(&prog_idr, prog, 1, INT_MAX, GFP_ATOMIC);
1715 	if (id > 0)
1716 		prog->aux->id = id;
1717 	spin_unlock_bh(&prog_idr_lock);
1718 	idr_preload_end();
1719 
1720 	/* id is in [1, INT_MAX) */
1721 	if (WARN_ON_ONCE(!id))
1722 		return -ENOSPC;
1723 
1724 	return id > 0 ? 0 : id;
1725 }
1726 
1727 void bpf_prog_free_id(struct bpf_prog *prog, bool do_idr_lock)
1728 {
1729 	unsigned long flags;
1730 
1731 	/* cBPF to eBPF migrations are currently not in the idr store.
1732 	 * Offloaded programs are removed from the store when their device
1733 	 * disappears - even if someone grabs an fd to them they are unusable,
1734 	 * simply waiting for refcnt to drop to be freed.
1735 	 */
1736 	if (!prog->aux->id)
1737 		return;
1738 
1739 	if (do_idr_lock)
1740 		spin_lock_irqsave(&prog_idr_lock, flags);
1741 	else
1742 		__acquire(&prog_idr_lock);
1743 
1744 	idr_remove(&prog_idr, prog->aux->id);
1745 	prog->aux->id = 0;
1746 
1747 	if (do_idr_lock)
1748 		spin_unlock_irqrestore(&prog_idr_lock, flags);
1749 	else
1750 		__release(&prog_idr_lock);
1751 }
1752 
1753 static void __bpf_prog_put_rcu(struct rcu_head *rcu)
1754 {
1755 	struct bpf_prog_aux *aux = container_of(rcu, struct bpf_prog_aux, rcu);
1756 
1757 	kvfree(aux->func_info);
1758 	kfree(aux->func_info_aux);
1759 	free_uid(aux->user);
1760 	security_bpf_prog_free(aux);
1761 	bpf_prog_free(aux->prog);
1762 }
1763 
1764 static void __bpf_prog_put_noref(struct bpf_prog *prog, bool deferred)
1765 {
1766 	bpf_prog_kallsyms_del_all(prog);
1767 	btf_put(prog->aux->btf);
1768 	kvfree(prog->aux->jited_linfo);
1769 	kvfree(prog->aux->linfo);
1770 	kfree(prog->aux->kfunc_tab);
1771 	if (prog->aux->attach_btf)
1772 		btf_put(prog->aux->attach_btf);
1773 
1774 	if (deferred) {
1775 		if (prog->aux->sleepable)
1776 			call_rcu_tasks_trace(&prog->aux->rcu, __bpf_prog_put_rcu);
1777 		else
1778 			call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu);
1779 	} else {
1780 		__bpf_prog_put_rcu(&prog->aux->rcu);
1781 	}
1782 }
1783 
1784 static void bpf_prog_put_deferred(struct work_struct *work)
1785 {
1786 	struct bpf_prog_aux *aux;
1787 	struct bpf_prog *prog;
1788 
1789 	aux = container_of(work, struct bpf_prog_aux, work);
1790 	prog = aux->prog;
1791 	perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_UNLOAD, 0);
1792 	bpf_audit_prog(prog, BPF_AUDIT_UNLOAD);
1793 	__bpf_prog_put_noref(prog, true);
1794 }
1795 
1796 static void __bpf_prog_put(struct bpf_prog *prog, bool do_idr_lock)
1797 {
1798 	struct bpf_prog_aux *aux = prog->aux;
1799 
1800 	if (atomic64_dec_and_test(&aux->refcnt)) {
1801 		/* bpf_prog_free_id() must be called first */
1802 		bpf_prog_free_id(prog, do_idr_lock);
1803 
1804 		if (in_irq() || irqs_disabled()) {
1805 			INIT_WORK(&aux->work, bpf_prog_put_deferred);
1806 			schedule_work(&aux->work);
1807 		} else {
1808 			bpf_prog_put_deferred(&aux->work);
1809 		}
1810 	}
1811 }
1812 
1813 void bpf_prog_put(struct bpf_prog *prog)
1814 {
1815 	__bpf_prog_put(prog, true);
1816 }
1817 EXPORT_SYMBOL_GPL(bpf_prog_put);
1818 
1819 static int bpf_prog_release(struct inode *inode, struct file *filp)
1820 {
1821 	struct bpf_prog *prog = filp->private_data;
1822 
1823 	bpf_prog_put(prog);
1824 	return 0;
1825 }
1826 
1827 struct bpf_prog_kstats {
1828 	u64 nsecs;
1829 	u64 cnt;
1830 	u64 misses;
1831 };
1832 
1833 static void bpf_prog_get_stats(const struct bpf_prog *prog,
1834 			       struct bpf_prog_kstats *stats)
1835 {
1836 	u64 nsecs = 0, cnt = 0, misses = 0;
1837 	int cpu;
1838 
1839 	for_each_possible_cpu(cpu) {
1840 		const struct bpf_prog_stats *st;
1841 		unsigned int start;
1842 		u64 tnsecs, tcnt, tmisses;
1843 
1844 		st = per_cpu_ptr(prog->stats, cpu);
1845 		do {
1846 			start = u64_stats_fetch_begin_irq(&st->syncp);
1847 			tnsecs = u64_stats_read(&st->nsecs);
1848 			tcnt = u64_stats_read(&st->cnt);
1849 			tmisses = u64_stats_read(&st->misses);
1850 		} while (u64_stats_fetch_retry_irq(&st->syncp, start));
1851 		nsecs += tnsecs;
1852 		cnt += tcnt;
1853 		misses += tmisses;
1854 	}
1855 	stats->nsecs = nsecs;
1856 	stats->cnt = cnt;
1857 	stats->misses = misses;
1858 }
1859 
1860 #ifdef CONFIG_PROC_FS
1861 static void bpf_prog_show_fdinfo(struct seq_file *m, struct file *filp)
1862 {
1863 	const struct bpf_prog *prog = filp->private_data;
1864 	char prog_tag[sizeof(prog->tag) * 2 + 1] = { };
1865 	struct bpf_prog_kstats stats;
1866 
1867 	bpf_prog_get_stats(prog, &stats);
1868 	bin2hex(prog_tag, prog->tag, sizeof(prog->tag));
1869 	seq_printf(m,
1870 		   "prog_type:\t%u\n"
1871 		   "prog_jited:\t%u\n"
1872 		   "prog_tag:\t%s\n"
1873 		   "memlock:\t%llu\n"
1874 		   "prog_id:\t%u\n"
1875 		   "run_time_ns:\t%llu\n"
1876 		   "run_cnt:\t%llu\n"
1877 		   "recursion_misses:\t%llu\n"
1878 		   "verified_insns:\t%u\n",
1879 		   prog->type,
1880 		   prog->jited,
1881 		   prog_tag,
1882 		   prog->pages * 1ULL << PAGE_SHIFT,
1883 		   prog->aux->id,
1884 		   stats.nsecs,
1885 		   stats.cnt,
1886 		   stats.misses,
1887 		   prog->aux->verified_insns);
1888 }
1889 #endif
1890 
1891 const struct file_operations bpf_prog_fops = {
1892 #ifdef CONFIG_PROC_FS
1893 	.show_fdinfo	= bpf_prog_show_fdinfo,
1894 #endif
1895 	.release	= bpf_prog_release,
1896 	.read		= bpf_dummy_read,
1897 	.write		= bpf_dummy_write,
1898 };
1899 
1900 int bpf_prog_new_fd(struct bpf_prog *prog)
1901 {
1902 	int ret;
1903 
1904 	ret = security_bpf_prog(prog);
1905 	if (ret < 0)
1906 		return ret;
1907 
1908 	return anon_inode_getfd("bpf-prog", &bpf_prog_fops, prog,
1909 				O_RDWR | O_CLOEXEC);
1910 }
1911 
1912 static struct bpf_prog *____bpf_prog_get(struct fd f)
1913 {
1914 	if (!f.file)
1915 		return ERR_PTR(-EBADF);
1916 	if (f.file->f_op != &bpf_prog_fops) {
1917 		fdput(f);
1918 		return ERR_PTR(-EINVAL);
1919 	}
1920 
1921 	return f.file->private_data;
1922 }
1923 
1924 void bpf_prog_add(struct bpf_prog *prog, int i)
1925 {
1926 	atomic64_add(i, &prog->aux->refcnt);
1927 }
1928 EXPORT_SYMBOL_GPL(bpf_prog_add);
1929 
1930 void bpf_prog_sub(struct bpf_prog *prog, int i)
1931 {
1932 	/* Only to be used for undoing previous bpf_prog_add() in some
1933 	 * error path. We still know that another entity in our call
1934 	 * path holds a reference to the program, thus atomic_sub() can
1935 	 * be safely used in such cases!
1936 	 */
1937 	WARN_ON(atomic64_sub_return(i, &prog->aux->refcnt) == 0);
1938 }
1939 EXPORT_SYMBOL_GPL(bpf_prog_sub);
1940 
1941 void bpf_prog_inc(struct bpf_prog *prog)
1942 {
1943 	atomic64_inc(&prog->aux->refcnt);
1944 }
1945 EXPORT_SYMBOL_GPL(bpf_prog_inc);
1946 
1947 /* prog_idr_lock should have been held */
1948 struct bpf_prog *bpf_prog_inc_not_zero(struct bpf_prog *prog)
1949 {
1950 	int refold;
1951 
1952 	refold = atomic64_fetch_add_unless(&prog->aux->refcnt, 1, 0);
1953 
1954 	if (!refold)
1955 		return ERR_PTR(-ENOENT);
1956 
1957 	return prog;
1958 }
1959 EXPORT_SYMBOL_GPL(bpf_prog_inc_not_zero);
1960 
1961 bool bpf_prog_get_ok(struct bpf_prog *prog,
1962 			    enum bpf_prog_type *attach_type, bool attach_drv)
1963 {
1964 	/* not an attachment, just a refcount inc, always allow */
1965 	if (!attach_type)
1966 		return true;
1967 
1968 	if (prog->type != *attach_type)
1969 		return false;
1970 	if (bpf_prog_is_dev_bound(prog->aux) && !attach_drv)
1971 		return false;
1972 
1973 	return true;
1974 }
1975 
1976 static struct bpf_prog *__bpf_prog_get(u32 ufd, enum bpf_prog_type *attach_type,
1977 				       bool attach_drv)
1978 {
1979 	struct fd f = fdget(ufd);
1980 	struct bpf_prog *prog;
1981 
1982 	prog = ____bpf_prog_get(f);
1983 	if (IS_ERR(prog))
1984 		return prog;
1985 	if (!bpf_prog_get_ok(prog, attach_type, attach_drv)) {
1986 		prog = ERR_PTR(-EINVAL);
1987 		goto out;
1988 	}
1989 
1990 	bpf_prog_inc(prog);
1991 out:
1992 	fdput(f);
1993 	return prog;
1994 }
1995 
1996 struct bpf_prog *bpf_prog_get(u32 ufd)
1997 {
1998 	return __bpf_prog_get(ufd, NULL, false);
1999 }
2000 
2001 struct bpf_prog *bpf_prog_get_type_dev(u32 ufd, enum bpf_prog_type type,
2002 				       bool attach_drv)
2003 {
2004 	return __bpf_prog_get(ufd, &type, attach_drv);
2005 }
2006 EXPORT_SYMBOL_GPL(bpf_prog_get_type_dev);
2007 
2008 /* Initially all BPF programs could be loaded w/o specifying
2009  * expected_attach_type. Later for some of them specifying expected_attach_type
2010  * at load time became required so that program could be validated properly.
2011  * Programs of types that are allowed to be loaded both w/ and w/o (for
2012  * backward compatibility) expected_attach_type, should have the default attach
2013  * type assigned to expected_attach_type for the latter case, so that it can be
2014  * validated later at attach time.
2015  *
2016  * bpf_prog_load_fixup_attach_type() sets expected_attach_type in @attr if
2017  * prog type requires it but has some attach types that have to be backward
2018  * compatible.
2019  */
2020 static void bpf_prog_load_fixup_attach_type(union bpf_attr *attr)
2021 {
2022 	switch (attr->prog_type) {
2023 	case BPF_PROG_TYPE_CGROUP_SOCK:
2024 		/* Unfortunately BPF_ATTACH_TYPE_UNSPEC enumeration doesn't
2025 		 * exist so checking for non-zero is the way to go here.
2026 		 */
2027 		if (!attr->expected_attach_type)
2028 			attr->expected_attach_type =
2029 				BPF_CGROUP_INET_SOCK_CREATE;
2030 		break;
2031 	case BPF_PROG_TYPE_SK_REUSEPORT:
2032 		if (!attr->expected_attach_type)
2033 			attr->expected_attach_type =
2034 				BPF_SK_REUSEPORT_SELECT;
2035 		break;
2036 	}
2037 }
2038 
2039 static int
2040 bpf_prog_load_check_attach(enum bpf_prog_type prog_type,
2041 			   enum bpf_attach_type expected_attach_type,
2042 			   struct btf *attach_btf, u32 btf_id,
2043 			   struct bpf_prog *dst_prog)
2044 {
2045 	if (btf_id) {
2046 		if (btf_id > BTF_MAX_TYPE)
2047 			return -EINVAL;
2048 
2049 		if (!attach_btf && !dst_prog)
2050 			return -EINVAL;
2051 
2052 		switch (prog_type) {
2053 		case BPF_PROG_TYPE_TRACING:
2054 		case BPF_PROG_TYPE_LSM:
2055 		case BPF_PROG_TYPE_STRUCT_OPS:
2056 		case BPF_PROG_TYPE_EXT:
2057 			break;
2058 		default:
2059 			return -EINVAL;
2060 		}
2061 	}
2062 
2063 	if (attach_btf && (!btf_id || dst_prog))
2064 		return -EINVAL;
2065 
2066 	if (dst_prog && prog_type != BPF_PROG_TYPE_TRACING &&
2067 	    prog_type != BPF_PROG_TYPE_EXT)
2068 		return -EINVAL;
2069 
2070 	switch (prog_type) {
2071 	case BPF_PROG_TYPE_CGROUP_SOCK:
2072 		switch (expected_attach_type) {
2073 		case BPF_CGROUP_INET_SOCK_CREATE:
2074 		case BPF_CGROUP_INET_SOCK_RELEASE:
2075 		case BPF_CGROUP_INET4_POST_BIND:
2076 		case BPF_CGROUP_INET6_POST_BIND:
2077 			return 0;
2078 		default:
2079 			return -EINVAL;
2080 		}
2081 	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
2082 		switch (expected_attach_type) {
2083 		case BPF_CGROUP_INET4_BIND:
2084 		case BPF_CGROUP_INET6_BIND:
2085 		case BPF_CGROUP_INET4_CONNECT:
2086 		case BPF_CGROUP_INET6_CONNECT:
2087 		case BPF_CGROUP_INET4_GETPEERNAME:
2088 		case BPF_CGROUP_INET6_GETPEERNAME:
2089 		case BPF_CGROUP_INET4_GETSOCKNAME:
2090 		case BPF_CGROUP_INET6_GETSOCKNAME:
2091 		case BPF_CGROUP_UDP4_SENDMSG:
2092 		case BPF_CGROUP_UDP6_SENDMSG:
2093 		case BPF_CGROUP_UDP4_RECVMSG:
2094 		case BPF_CGROUP_UDP6_RECVMSG:
2095 			return 0;
2096 		default:
2097 			return -EINVAL;
2098 		}
2099 	case BPF_PROG_TYPE_CGROUP_SKB:
2100 		switch (expected_attach_type) {
2101 		case BPF_CGROUP_INET_INGRESS:
2102 		case BPF_CGROUP_INET_EGRESS:
2103 			return 0;
2104 		default:
2105 			return -EINVAL;
2106 		}
2107 	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
2108 		switch (expected_attach_type) {
2109 		case BPF_CGROUP_SETSOCKOPT:
2110 		case BPF_CGROUP_GETSOCKOPT:
2111 			return 0;
2112 		default:
2113 			return -EINVAL;
2114 		}
2115 	case BPF_PROG_TYPE_SK_LOOKUP:
2116 		if (expected_attach_type == BPF_SK_LOOKUP)
2117 			return 0;
2118 		return -EINVAL;
2119 	case BPF_PROG_TYPE_SK_REUSEPORT:
2120 		switch (expected_attach_type) {
2121 		case BPF_SK_REUSEPORT_SELECT:
2122 		case BPF_SK_REUSEPORT_SELECT_OR_MIGRATE:
2123 			return 0;
2124 		default:
2125 			return -EINVAL;
2126 		}
2127 	case BPF_PROG_TYPE_SYSCALL:
2128 	case BPF_PROG_TYPE_EXT:
2129 		if (expected_attach_type)
2130 			return -EINVAL;
2131 		fallthrough;
2132 	default:
2133 		return 0;
2134 	}
2135 }
2136 
2137 static bool is_net_admin_prog_type(enum bpf_prog_type prog_type)
2138 {
2139 	switch (prog_type) {
2140 	case BPF_PROG_TYPE_SCHED_CLS:
2141 	case BPF_PROG_TYPE_SCHED_ACT:
2142 	case BPF_PROG_TYPE_XDP:
2143 	case BPF_PROG_TYPE_LWT_IN:
2144 	case BPF_PROG_TYPE_LWT_OUT:
2145 	case BPF_PROG_TYPE_LWT_XMIT:
2146 	case BPF_PROG_TYPE_LWT_SEG6LOCAL:
2147 	case BPF_PROG_TYPE_SK_SKB:
2148 	case BPF_PROG_TYPE_SK_MSG:
2149 	case BPF_PROG_TYPE_LIRC_MODE2:
2150 	case BPF_PROG_TYPE_FLOW_DISSECTOR:
2151 	case BPF_PROG_TYPE_CGROUP_DEVICE:
2152 	case BPF_PROG_TYPE_CGROUP_SOCK:
2153 	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
2154 	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
2155 	case BPF_PROG_TYPE_CGROUP_SYSCTL:
2156 	case BPF_PROG_TYPE_SOCK_OPS:
2157 	case BPF_PROG_TYPE_EXT: /* extends any prog */
2158 		return true;
2159 	case BPF_PROG_TYPE_CGROUP_SKB:
2160 		/* always unpriv */
2161 	case BPF_PROG_TYPE_SK_REUSEPORT:
2162 		/* equivalent to SOCKET_FILTER. need CAP_BPF only */
2163 	default:
2164 		return false;
2165 	}
2166 }
2167 
2168 static bool is_perfmon_prog_type(enum bpf_prog_type prog_type)
2169 {
2170 	switch (prog_type) {
2171 	case BPF_PROG_TYPE_KPROBE:
2172 	case BPF_PROG_TYPE_TRACEPOINT:
2173 	case BPF_PROG_TYPE_PERF_EVENT:
2174 	case BPF_PROG_TYPE_RAW_TRACEPOINT:
2175 	case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE:
2176 	case BPF_PROG_TYPE_TRACING:
2177 	case BPF_PROG_TYPE_LSM:
2178 	case BPF_PROG_TYPE_STRUCT_OPS: /* has access to struct sock */
2179 	case BPF_PROG_TYPE_EXT: /* extends any prog */
2180 		return true;
2181 	default:
2182 		return false;
2183 	}
2184 }
2185 
2186 /* last field in 'union bpf_attr' used by this command */
2187 #define	BPF_PROG_LOAD_LAST_FIELD fd_array
2188 
2189 static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr)
2190 {
2191 	enum bpf_prog_type type = attr->prog_type;
2192 	struct bpf_prog *prog, *dst_prog = NULL;
2193 	struct btf *attach_btf = NULL;
2194 	int err;
2195 	char license[128];
2196 	bool is_gpl;
2197 
2198 	if (CHECK_ATTR(BPF_PROG_LOAD))
2199 		return -EINVAL;
2200 
2201 	if (attr->prog_flags & ~(BPF_F_STRICT_ALIGNMENT |
2202 				 BPF_F_ANY_ALIGNMENT |
2203 				 BPF_F_TEST_STATE_FREQ |
2204 				 BPF_F_SLEEPABLE |
2205 				 BPF_F_TEST_RND_HI32))
2206 		return -EINVAL;
2207 
2208 	if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) &&
2209 	    (attr->prog_flags & BPF_F_ANY_ALIGNMENT) &&
2210 	    !bpf_capable())
2211 		return -EPERM;
2212 
2213 	/* copy eBPF program license from user space */
2214 	if (strncpy_from_bpfptr(license,
2215 				make_bpfptr(attr->license, uattr.is_kernel),
2216 				sizeof(license) - 1) < 0)
2217 		return -EFAULT;
2218 	license[sizeof(license) - 1] = 0;
2219 
2220 	/* eBPF programs must be GPL compatible to use GPL-ed functions */
2221 	is_gpl = license_is_gpl_compatible(license);
2222 
2223 	if (attr->insn_cnt == 0 ||
2224 	    attr->insn_cnt > (bpf_capable() ? BPF_COMPLEXITY_LIMIT_INSNS : BPF_MAXINSNS))
2225 		return -E2BIG;
2226 	if (type != BPF_PROG_TYPE_SOCKET_FILTER &&
2227 	    type != BPF_PROG_TYPE_CGROUP_SKB &&
2228 	    !bpf_capable())
2229 		return -EPERM;
2230 
2231 	if (is_net_admin_prog_type(type) && !capable(CAP_NET_ADMIN) && !capable(CAP_SYS_ADMIN))
2232 		return -EPERM;
2233 	if (is_perfmon_prog_type(type) && !perfmon_capable())
2234 		return -EPERM;
2235 
2236 	/* attach_prog_fd/attach_btf_obj_fd can specify fd of either bpf_prog
2237 	 * or btf, we need to check which one it is
2238 	 */
2239 	if (attr->attach_prog_fd) {
2240 		dst_prog = bpf_prog_get(attr->attach_prog_fd);
2241 		if (IS_ERR(dst_prog)) {
2242 			dst_prog = NULL;
2243 			attach_btf = btf_get_by_fd(attr->attach_btf_obj_fd);
2244 			if (IS_ERR(attach_btf))
2245 				return -EINVAL;
2246 			if (!btf_is_kernel(attach_btf)) {
2247 				/* attaching through specifying bpf_prog's BTF
2248 				 * objects directly might be supported eventually
2249 				 */
2250 				btf_put(attach_btf);
2251 				return -ENOTSUPP;
2252 			}
2253 		}
2254 	} else if (attr->attach_btf_id) {
2255 		/* fall back to vmlinux BTF, if BTF type ID is specified */
2256 		attach_btf = bpf_get_btf_vmlinux();
2257 		if (IS_ERR(attach_btf))
2258 			return PTR_ERR(attach_btf);
2259 		if (!attach_btf)
2260 			return -EINVAL;
2261 		btf_get(attach_btf);
2262 	}
2263 
2264 	bpf_prog_load_fixup_attach_type(attr);
2265 	if (bpf_prog_load_check_attach(type, attr->expected_attach_type,
2266 				       attach_btf, attr->attach_btf_id,
2267 				       dst_prog)) {
2268 		if (dst_prog)
2269 			bpf_prog_put(dst_prog);
2270 		if (attach_btf)
2271 			btf_put(attach_btf);
2272 		return -EINVAL;
2273 	}
2274 
2275 	/* plain bpf_prog allocation */
2276 	prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER);
2277 	if (!prog) {
2278 		if (dst_prog)
2279 			bpf_prog_put(dst_prog);
2280 		if (attach_btf)
2281 			btf_put(attach_btf);
2282 		return -ENOMEM;
2283 	}
2284 
2285 	prog->expected_attach_type = attr->expected_attach_type;
2286 	prog->aux->attach_btf = attach_btf;
2287 	prog->aux->attach_btf_id = attr->attach_btf_id;
2288 	prog->aux->dst_prog = dst_prog;
2289 	prog->aux->offload_requested = !!attr->prog_ifindex;
2290 	prog->aux->sleepable = attr->prog_flags & BPF_F_SLEEPABLE;
2291 
2292 	err = security_bpf_prog_alloc(prog->aux);
2293 	if (err)
2294 		goto free_prog;
2295 
2296 	prog->aux->user = get_current_user();
2297 	prog->len = attr->insn_cnt;
2298 
2299 	err = -EFAULT;
2300 	if (copy_from_bpfptr(prog->insns,
2301 			     make_bpfptr(attr->insns, uattr.is_kernel),
2302 			     bpf_prog_insn_size(prog)) != 0)
2303 		goto free_prog_sec;
2304 
2305 	prog->orig_prog = NULL;
2306 	prog->jited = 0;
2307 
2308 	atomic64_set(&prog->aux->refcnt, 1);
2309 	prog->gpl_compatible = is_gpl ? 1 : 0;
2310 
2311 	if (bpf_prog_is_dev_bound(prog->aux)) {
2312 		err = bpf_prog_offload_init(prog, attr);
2313 		if (err)
2314 			goto free_prog_sec;
2315 	}
2316 
2317 	/* find program type: socket_filter vs tracing_filter */
2318 	err = find_prog_type(type, prog);
2319 	if (err < 0)
2320 		goto free_prog_sec;
2321 
2322 	prog->aux->load_time = ktime_get_boottime_ns();
2323 	err = bpf_obj_name_cpy(prog->aux->name, attr->prog_name,
2324 			       sizeof(attr->prog_name));
2325 	if (err < 0)
2326 		goto free_prog_sec;
2327 
2328 	/* run eBPF verifier */
2329 	err = bpf_check(&prog, attr, uattr);
2330 	if (err < 0)
2331 		goto free_used_maps;
2332 
2333 	prog = bpf_prog_select_runtime(prog, &err);
2334 	if (err < 0)
2335 		goto free_used_maps;
2336 
2337 	err = bpf_prog_alloc_id(prog);
2338 	if (err)
2339 		goto free_used_maps;
2340 
2341 	/* Upon success of bpf_prog_alloc_id(), the BPF prog is
2342 	 * effectively publicly exposed. However, retrieving via
2343 	 * bpf_prog_get_fd_by_id() will take another reference,
2344 	 * therefore it cannot be gone underneath us.
2345 	 *
2346 	 * Only for the time /after/ successful bpf_prog_new_fd()
2347 	 * and before returning to userspace, we might just hold
2348 	 * one reference and any parallel close on that fd could
2349 	 * rip everything out. Hence, below notifications must
2350 	 * happen before bpf_prog_new_fd().
2351 	 *
2352 	 * Also, any failure handling from this point onwards must
2353 	 * be using bpf_prog_put() given the program is exposed.
2354 	 */
2355 	bpf_prog_kallsyms_add(prog);
2356 	perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_LOAD, 0);
2357 	bpf_audit_prog(prog, BPF_AUDIT_LOAD);
2358 
2359 	err = bpf_prog_new_fd(prog);
2360 	if (err < 0)
2361 		bpf_prog_put(prog);
2362 	return err;
2363 
2364 free_used_maps:
2365 	/* In case we have subprogs, we need to wait for a grace
2366 	 * period before we can tear down JIT memory since symbols
2367 	 * are already exposed under kallsyms.
2368 	 */
2369 	__bpf_prog_put_noref(prog, prog->aux->func_cnt);
2370 	return err;
2371 free_prog_sec:
2372 	free_uid(prog->aux->user);
2373 	security_bpf_prog_free(prog->aux);
2374 free_prog:
2375 	if (prog->aux->attach_btf)
2376 		btf_put(prog->aux->attach_btf);
2377 	bpf_prog_free(prog);
2378 	return err;
2379 }
2380 
2381 #define BPF_OBJ_LAST_FIELD file_flags
2382 
2383 static int bpf_obj_pin(const union bpf_attr *attr)
2384 {
2385 	if (CHECK_ATTR(BPF_OBJ) || attr->file_flags != 0)
2386 		return -EINVAL;
2387 
2388 	return bpf_obj_pin_user(attr->bpf_fd, u64_to_user_ptr(attr->pathname));
2389 }
2390 
2391 static int bpf_obj_get(const union bpf_attr *attr)
2392 {
2393 	if (CHECK_ATTR(BPF_OBJ) || attr->bpf_fd != 0 ||
2394 	    attr->file_flags & ~BPF_OBJ_FLAG_MASK)
2395 		return -EINVAL;
2396 
2397 	return bpf_obj_get_user(u64_to_user_ptr(attr->pathname),
2398 				attr->file_flags);
2399 }
2400 
2401 void bpf_link_init(struct bpf_link *link, enum bpf_link_type type,
2402 		   const struct bpf_link_ops *ops, struct bpf_prog *prog)
2403 {
2404 	atomic64_set(&link->refcnt, 1);
2405 	link->type = type;
2406 	link->id = 0;
2407 	link->ops = ops;
2408 	link->prog = prog;
2409 }
2410 
2411 static void bpf_link_free_id(int id)
2412 {
2413 	if (!id)
2414 		return;
2415 
2416 	spin_lock_bh(&link_idr_lock);
2417 	idr_remove(&link_idr, id);
2418 	spin_unlock_bh(&link_idr_lock);
2419 }
2420 
2421 /* Clean up bpf_link and corresponding anon_inode file and FD. After
2422  * anon_inode is created, bpf_link can't be just kfree()'d due to deferred
2423  * anon_inode's release() call. This helper marksbpf_link as
2424  * defunct, releases anon_inode file and puts reserved FD. bpf_prog's refcnt
2425  * is not decremented, it's the responsibility of a calling code that failed
2426  * to complete bpf_link initialization.
2427  */
2428 void bpf_link_cleanup(struct bpf_link_primer *primer)
2429 {
2430 	primer->link->prog = NULL;
2431 	bpf_link_free_id(primer->id);
2432 	fput(primer->file);
2433 	put_unused_fd(primer->fd);
2434 }
2435 
2436 void bpf_link_inc(struct bpf_link *link)
2437 {
2438 	atomic64_inc(&link->refcnt);
2439 }
2440 
2441 /* bpf_link_free is guaranteed to be called from process context */
2442 static void bpf_link_free(struct bpf_link *link)
2443 {
2444 	bpf_link_free_id(link->id);
2445 	if (link->prog) {
2446 		/* detach BPF program, clean up used resources */
2447 		link->ops->release(link);
2448 		bpf_prog_put(link->prog);
2449 	}
2450 	/* free bpf_link and its containing memory */
2451 	link->ops->dealloc(link);
2452 }
2453 
2454 static void bpf_link_put_deferred(struct work_struct *work)
2455 {
2456 	struct bpf_link *link = container_of(work, struct bpf_link, work);
2457 
2458 	bpf_link_free(link);
2459 }
2460 
2461 /* bpf_link_put can be called from atomic context, but ensures that resources
2462  * are freed from process context
2463  */
2464 void bpf_link_put(struct bpf_link *link)
2465 {
2466 	if (!atomic64_dec_and_test(&link->refcnt))
2467 		return;
2468 
2469 	if (in_atomic()) {
2470 		INIT_WORK(&link->work, bpf_link_put_deferred);
2471 		schedule_work(&link->work);
2472 	} else {
2473 		bpf_link_free(link);
2474 	}
2475 }
2476 
2477 static int bpf_link_release(struct inode *inode, struct file *filp)
2478 {
2479 	struct bpf_link *link = filp->private_data;
2480 
2481 	bpf_link_put(link);
2482 	return 0;
2483 }
2484 
2485 #ifdef CONFIG_PROC_FS
2486 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type)
2487 #define BPF_MAP_TYPE(_id, _ops)
2488 #define BPF_LINK_TYPE(_id, _name) [_id] = #_name,
2489 static const char *bpf_link_type_strs[] = {
2490 	[BPF_LINK_TYPE_UNSPEC] = "<invalid>",
2491 #include <linux/bpf_types.h>
2492 };
2493 #undef BPF_PROG_TYPE
2494 #undef BPF_MAP_TYPE
2495 #undef BPF_LINK_TYPE
2496 
2497 static void bpf_link_show_fdinfo(struct seq_file *m, struct file *filp)
2498 {
2499 	const struct bpf_link *link = filp->private_data;
2500 	const struct bpf_prog *prog = link->prog;
2501 	char prog_tag[sizeof(prog->tag) * 2 + 1] = { };
2502 
2503 	bin2hex(prog_tag, prog->tag, sizeof(prog->tag));
2504 	seq_printf(m,
2505 		   "link_type:\t%s\n"
2506 		   "link_id:\t%u\n"
2507 		   "prog_tag:\t%s\n"
2508 		   "prog_id:\t%u\n",
2509 		   bpf_link_type_strs[link->type],
2510 		   link->id,
2511 		   prog_tag,
2512 		   prog->aux->id);
2513 	if (link->ops->show_fdinfo)
2514 		link->ops->show_fdinfo(link, m);
2515 }
2516 #endif
2517 
2518 static const struct file_operations bpf_link_fops = {
2519 #ifdef CONFIG_PROC_FS
2520 	.show_fdinfo	= bpf_link_show_fdinfo,
2521 #endif
2522 	.release	= bpf_link_release,
2523 	.read		= bpf_dummy_read,
2524 	.write		= bpf_dummy_write,
2525 };
2526 
2527 static int bpf_link_alloc_id(struct bpf_link *link)
2528 {
2529 	int id;
2530 
2531 	idr_preload(GFP_KERNEL);
2532 	spin_lock_bh(&link_idr_lock);
2533 	id = idr_alloc_cyclic(&link_idr, link, 1, INT_MAX, GFP_ATOMIC);
2534 	spin_unlock_bh(&link_idr_lock);
2535 	idr_preload_end();
2536 
2537 	return id;
2538 }
2539 
2540 /* Prepare bpf_link to be exposed to user-space by allocating anon_inode file,
2541  * reserving unused FD and allocating ID from link_idr. This is to be paired
2542  * with bpf_link_settle() to install FD and ID and expose bpf_link to
2543  * user-space, if bpf_link is successfully attached. If not, bpf_link and
2544  * pre-allocated resources are to be freed with bpf_cleanup() call. All the
2545  * transient state is passed around in struct bpf_link_primer.
2546  * This is preferred way to create and initialize bpf_link, especially when
2547  * there are complicated and expensive operations inbetween creating bpf_link
2548  * itself and attaching it to BPF hook. By using bpf_link_prime() and
2549  * bpf_link_settle() kernel code using bpf_link doesn't have to perform
2550  * expensive (and potentially failing) roll back operations in a rare case
2551  * that file, FD, or ID can't be allocated.
2552  */
2553 int bpf_link_prime(struct bpf_link *link, struct bpf_link_primer *primer)
2554 {
2555 	struct file *file;
2556 	int fd, id;
2557 
2558 	fd = get_unused_fd_flags(O_CLOEXEC);
2559 	if (fd < 0)
2560 		return fd;
2561 
2562 
2563 	id = bpf_link_alloc_id(link);
2564 	if (id < 0) {
2565 		put_unused_fd(fd);
2566 		return id;
2567 	}
2568 
2569 	file = anon_inode_getfile("bpf_link", &bpf_link_fops, link, O_CLOEXEC);
2570 	if (IS_ERR(file)) {
2571 		bpf_link_free_id(id);
2572 		put_unused_fd(fd);
2573 		return PTR_ERR(file);
2574 	}
2575 
2576 	primer->link = link;
2577 	primer->file = file;
2578 	primer->fd = fd;
2579 	primer->id = id;
2580 	return 0;
2581 }
2582 
2583 int bpf_link_settle(struct bpf_link_primer *primer)
2584 {
2585 	/* make bpf_link fetchable by ID */
2586 	spin_lock_bh(&link_idr_lock);
2587 	primer->link->id = primer->id;
2588 	spin_unlock_bh(&link_idr_lock);
2589 	/* make bpf_link fetchable by FD */
2590 	fd_install(primer->fd, primer->file);
2591 	/* pass through installed FD */
2592 	return primer->fd;
2593 }
2594 
2595 int bpf_link_new_fd(struct bpf_link *link)
2596 {
2597 	return anon_inode_getfd("bpf-link", &bpf_link_fops, link, O_CLOEXEC);
2598 }
2599 
2600 struct bpf_link *bpf_link_get_from_fd(u32 ufd)
2601 {
2602 	struct fd f = fdget(ufd);
2603 	struct bpf_link *link;
2604 
2605 	if (!f.file)
2606 		return ERR_PTR(-EBADF);
2607 	if (f.file->f_op != &bpf_link_fops) {
2608 		fdput(f);
2609 		return ERR_PTR(-EINVAL);
2610 	}
2611 
2612 	link = f.file->private_data;
2613 	bpf_link_inc(link);
2614 	fdput(f);
2615 
2616 	return link;
2617 }
2618 
2619 struct bpf_tracing_link {
2620 	struct bpf_link link;
2621 	enum bpf_attach_type attach_type;
2622 	struct bpf_trampoline *trampoline;
2623 	struct bpf_prog *tgt_prog;
2624 };
2625 
2626 static void bpf_tracing_link_release(struct bpf_link *link)
2627 {
2628 	struct bpf_tracing_link *tr_link =
2629 		container_of(link, struct bpf_tracing_link, link);
2630 
2631 	WARN_ON_ONCE(bpf_trampoline_unlink_prog(link->prog,
2632 						tr_link->trampoline));
2633 
2634 	bpf_trampoline_put(tr_link->trampoline);
2635 
2636 	/* tgt_prog is NULL if target is a kernel function */
2637 	if (tr_link->tgt_prog)
2638 		bpf_prog_put(tr_link->tgt_prog);
2639 }
2640 
2641 static void bpf_tracing_link_dealloc(struct bpf_link *link)
2642 {
2643 	struct bpf_tracing_link *tr_link =
2644 		container_of(link, struct bpf_tracing_link, link);
2645 
2646 	kfree(tr_link);
2647 }
2648 
2649 static void bpf_tracing_link_show_fdinfo(const struct bpf_link *link,
2650 					 struct seq_file *seq)
2651 {
2652 	struct bpf_tracing_link *tr_link =
2653 		container_of(link, struct bpf_tracing_link, link);
2654 
2655 	seq_printf(seq,
2656 		   "attach_type:\t%d\n",
2657 		   tr_link->attach_type);
2658 }
2659 
2660 static int bpf_tracing_link_fill_link_info(const struct bpf_link *link,
2661 					   struct bpf_link_info *info)
2662 {
2663 	struct bpf_tracing_link *tr_link =
2664 		container_of(link, struct bpf_tracing_link, link);
2665 
2666 	info->tracing.attach_type = tr_link->attach_type;
2667 	bpf_trampoline_unpack_key(tr_link->trampoline->key,
2668 				  &info->tracing.target_obj_id,
2669 				  &info->tracing.target_btf_id);
2670 
2671 	return 0;
2672 }
2673 
2674 static const struct bpf_link_ops bpf_tracing_link_lops = {
2675 	.release = bpf_tracing_link_release,
2676 	.dealloc = bpf_tracing_link_dealloc,
2677 	.show_fdinfo = bpf_tracing_link_show_fdinfo,
2678 	.fill_link_info = bpf_tracing_link_fill_link_info,
2679 };
2680 
2681 static int bpf_tracing_prog_attach(struct bpf_prog *prog,
2682 				   int tgt_prog_fd,
2683 				   u32 btf_id)
2684 {
2685 	struct bpf_link_primer link_primer;
2686 	struct bpf_prog *tgt_prog = NULL;
2687 	struct bpf_trampoline *tr = NULL;
2688 	struct bpf_tracing_link *link;
2689 	u64 key = 0;
2690 	int err;
2691 
2692 	switch (prog->type) {
2693 	case BPF_PROG_TYPE_TRACING:
2694 		if (prog->expected_attach_type != BPF_TRACE_FENTRY &&
2695 		    prog->expected_attach_type != BPF_TRACE_FEXIT &&
2696 		    prog->expected_attach_type != BPF_MODIFY_RETURN) {
2697 			err = -EINVAL;
2698 			goto out_put_prog;
2699 		}
2700 		break;
2701 	case BPF_PROG_TYPE_EXT:
2702 		if (prog->expected_attach_type != 0) {
2703 			err = -EINVAL;
2704 			goto out_put_prog;
2705 		}
2706 		break;
2707 	case BPF_PROG_TYPE_LSM:
2708 		if (prog->expected_attach_type != BPF_LSM_MAC) {
2709 			err = -EINVAL;
2710 			goto out_put_prog;
2711 		}
2712 		break;
2713 	default:
2714 		err = -EINVAL;
2715 		goto out_put_prog;
2716 	}
2717 
2718 	if (!!tgt_prog_fd != !!btf_id) {
2719 		err = -EINVAL;
2720 		goto out_put_prog;
2721 	}
2722 
2723 	if (tgt_prog_fd) {
2724 		/* For now we only allow new targets for BPF_PROG_TYPE_EXT */
2725 		if (prog->type != BPF_PROG_TYPE_EXT) {
2726 			err = -EINVAL;
2727 			goto out_put_prog;
2728 		}
2729 
2730 		tgt_prog = bpf_prog_get(tgt_prog_fd);
2731 		if (IS_ERR(tgt_prog)) {
2732 			err = PTR_ERR(tgt_prog);
2733 			tgt_prog = NULL;
2734 			goto out_put_prog;
2735 		}
2736 
2737 		key = bpf_trampoline_compute_key(tgt_prog, NULL, btf_id);
2738 	}
2739 
2740 	link = kzalloc(sizeof(*link), GFP_USER);
2741 	if (!link) {
2742 		err = -ENOMEM;
2743 		goto out_put_prog;
2744 	}
2745 	bpf_link_init(&link->link, BPF_LINK_TYPE_TRACING,
2746 		      &bpf_tracing_link_lops, prog);
2747 	link->attach_type = prog->expected_attach_type;
2748 
2749 	mutex_lock(&prog->aux->dst_mutex);
2750 
2751 	/* There are a few possible cases here:
2752 	 *
2753 	 * - if prog->aux->dst_trampoline is set, the program was just loaded
2754 	 *   and not yet attached to anything, so we can use the values stored
2755 	 *   in prog->aux
2756 	 *
2757 	 * - if prog->aux->dst_trampoline is NULL, the program has already been
2758          *   attached to a target and its initial target was cleared (below)
2759 	 *
2760 	 * - if tgt_prog != NULL, the caller specified tgt_prog_fd +
2761 	 *   target_btf_id using the link_create API.
2762 	 *
2763 	 * - if tgt_prog == NULL when this function was called using the old
2764 	 *   raw_tracepoint_open API, and we need a target from prog->aux
2765 	 *
2766 	 * - if prog->aux->dst_trampoline and tgt_prog is NULL, the program
2767 	 *   was detached and is going for re-attachment.
2768 	 */
2769 	if (!prog->aux->dst_trampoline && !tgt_prog) {
2770 		/*
2771 		 * Allow re-attach for TRACING and LSM programs. If it's
2772 		 * currently linked, bpf_trampoline_link_prog will fail.
2773 		 * EXT programs need to specify tgt_prog_fd, so they
2774 		 * re-attach in separate code path.
2775 		 */
2776 		if (prog->type != BPF_PROG_TYPE_TRACING &&
2777 		    prog->type != BPF_PROG_TYPE_LSM) {
2778 			err = -EINVAL;
2779 			goto out_unlock;
2780 		}
2781 		btf_id = prog->aux->attach_btf_id;
2782 		key = bpf_trampoline_compute_key(NULL, prog->aux->attach_btf, btf_id);
2783 	}
2784 
2785 	if (!prog->aux->dst_trampoline ||
2786 	    (key && key != prog->aux->dst_trampoline->key)) {
2787 		/* If there is no saved target, or the specified target is
2788 		 * different from the destination specified at load time, we
2789 		 * need a new trampoline and a check for compatibility
2790 		 */
2791 		struct bpf_attach_target_info tgt_info = {};
2792 
2793 		err = bpf_check_attach_target(NULL, prog, tgt_prog, btf_id,
2794 					      &tgt_info);
2795 		if (err)
2796 			goto out_unlock;
2797 
2798 		tr = bpf_trampoline_get(key, &tgt_info);
2799 		if (!tr) {
2800 			err = -ENOMEM;
2801 			goto out_unlock;
2802 		}
2803 	} else {
2804 		/* The caller didn't specify a target, or the target was the
2805 		 * same as the destination supplied during program load. This
2806 		 * means we can reuse the trampoline and reference from program
2807 		 * load time, and there is no need to allocate a new one. This
2808 		 * can only happen once for any program, as the saved values in
2809 		 * prog->aux are cleared below.
2810 		 */
2811 		tr = prog->aux->dst_trampoline;
2812 		tgt_prog = prog->aux->dst_prog;
2813 	}
2814 
2815 	err = bpf_link_prime(&link->link, &link_primer);
2816 	if (err)
2817 		goto out_unlock;
2818 
2819 	err = bpf_trampoline_link_prog(prog, tr);
2820 	if (err) {
2821 		bpf_link_cleanup(&link_primer);
2822 		link = NULL;
2823 		goto out_unlock;
2824 	}
2825 
2826 	link->tgt_prog = tgt_prog;
2827 	link->trampoline = tr;
2828 
2829 	/* Always clear the trampoline and target prog from prog->aux to make
2830 	 * sure the original attach destination is not kept alive after a
2831 	 * program is (re-)attached to another target.
2832 	 */
2833 	if (prog->aux->dst_prog &&
2834 	    (tgt_prog_fd || tr != prog->aux->dst_trampoline))
2835 		/* got extra prog ref from syscall, or attaching to different prog */
2836 		bpf_prog_put(prog->aux->dst_prog);
2837 	if (prog->aux->dst_trampoline && tr != prog->aux->dst_trampoline)
2838 		/* we allocated a new trampoline, so free the old one */
2839 		bpf_trampoline_put(prog->aux->dst_trampoline);
2840 
2841 	prog->aux->dst_prog = NULL;
2842 	prog->aux->dst_trampoline = NULL;
2843 	mutex_unlock(&prog->aux->dst_mutex);
2844 
2845 	return bpf_link_settle(&link_primer);
2846 out_unlock:
2847 	if (tr && tr != prog->aux->dst_trampoline)
2848 		bpf_trampoline_put(tr);
2849 	mutex_unlock(&prog->aux->dst_mutex);
2850 	kfree(link);
2851 out_put_prog:
2852 	if (tgt_prog_fd && tgt_prog)
2853 		bpf_prog_put(tgt_prog);
2854 	return err;
2855 }
2856 
2857 struct bpf_raw_tp_link {
2858 	struct bpf_link link;
2859 	struct bpf_raw_event_map *btp;
2860 };
2861 
2862 static void bpf_raw_tp_link_release(struct bpf_link *link)
2863 {
2864 	struct bpf_raw_tp_link *raw_tp =
2865 		container_of(link, struct bpf_raw_tp_link, link);
2866 
2867 	bpf_probe_unregister(raw_tp->btp, raw_tp->link.prog);
2868 	bpf_put_raw_tracepoint(raw_tp->btp);
2869 }
2870 
2871 static void bpf_raw_tp_link_dealloc(struct bpf_link *link)
2872 {
2873 	struct bpf_raw_tp_link *raw_tp =
2874 		container_of(link, struct bpf_raw_tp_link, link);
2875 
2876 	kfree(raw_tp);
2877 }
2878 
2879 static void bpf_raw_tp_link_show_fdinfo(const struct bpf_link *link,
2880 					struct seq_file *seq)
2881 {
2882 	struct bpf_raw_tp_link *raw_tp_link =
2883 		container_of(link, struct bpf_raw_tp_link, link);
2884 
2885 	seq_printf(seq,
2886 		   "tp_name:\t%s\n",
2887 		   raw_tp_link->btp->tp->name);
2888 }
2889 
2890 static int bpf_raw_tp_link_fill_link_info(const struct bpf_link *link,
2891 					  struct bpf_link_info *info)
2892 {
2893 	struct bpf_raw_tp_link *raw_tp_link =
2894 		container_of(link, struct bpf_raw_tp_link, link);
2895 	char __user *ubuf = u64_to_user_ptr(info->raw_tracepoint.tp_name);
2896 	const char *tp_name = raw_tp_link->btp->tp->name;
2897 	u32 ulen = info->raw_tracepoint.tp_name_len;
2898 	size_t tp_len = strlen(tp_name);
2899 
2900 	if (!ulen ^ !ubuf)
2901 		return -EINVAL;
2902 
2903 	info->raw_tracepoint.tp_name_len = tp_len + 1;
2904 
2905 	if (!ubuf)
2906 		return 0;
2907 
2908 	if (ulen >= tp_len + 1) {
2909 		if (copy_to_user(ubuf, tp_name, tp_len + 1))
2910 			return -EFAULT;
2911 	} else {
2912 		char zero = '\0';
2913 
2914 		if (copy_to_user(ubuf, tp_name, ulen - 1))
2915 			return -EFAULT;
2916 		if (put_user(zero, ubuf + ulen - 1))
2917 			return -EFAULT;
2918 		return -ENOSPC;
2919 	}
2920 
2921 	return 0;
2922 }
2923 
2924 static const struct bpf_link_ops bpf_raw_tp_link_lops = {
2925 	.release = bpf_raw_tp_link_release,
2926 	.dealloc = bpf_raw_tp_link_dealloc,
2927 	.show_fdinfo = bpf_raw_tp_link_show_fdinfo,
2928 	.fill_link_info = bpf_raw_tp_link_fill_link_info,
2929 };
2930 
2931 #ifdef CONFIG_PERF_EVENTS
2932 struct bpf_perf_link {
2933 	struct bpf_link link;
2934 	struct file *perf_file;
2935 };
2936 
2937 static void bpf_perf_link_release(struct bpf_link *link)
2938 {
2939 	struct bpf_perf_link *perf_link = container_of(link, struct bpf_perf_link, link);
2940 	struct perf_event *event = perf_link->perf_file->private_data;
2941 
2942 	perf_event_free_bpf_prog(event);
2943 	fput(perf_link->perf_file);
2944 }
2945 
2946 static void bpf_perf_link_dealloc(struct bpf_link *link)
2947 {
2948 	struct bpf_perf_link *perf_link = container_of(link, struct bpf_perf_link, link);
2949 
2950 	kfree(perf_link);
2951 }
2952 
2953 static const struct bpf_link_ops bpf_perf_link_lops = {
2954 	.release = bpf_perf_link_release,
2955 	.dealloc = bpf_perf_link_dealloc,
2956 };
2957 
2958 static int bpf_perf_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
2959 {
2960 	struct bpf_link_primer link_primer;
2961 	struct bpf_perf_link *link;
2962 	struct perf_event *event;
2963 	struct file *perf_file;
2964 	int err;
2965 
2966 	if (attr->link_create.flags)
2967 		return -EINVAL;
2968 
2969 	perf_file = perf_event_get(attr->link_create.target_fd);
2970 	if (IS_ERR(perf_file))
2971 		return PTR_ERR(perf_file);
2972 
2973 	link = kzalloc(sizeof(*link), GFP_USER);
2974 	if (!link) {
2975 		err = -ENOMEM;
2976 		goto out_put_file;
2977 	}
2978 	bpf_link_init(&link->link, BPF_LINK_TYPE_PERF_EVENT, &bpf_perf_link_lops, prog);
2979 	link->perf_file = perf_file;
2980 
2981 	err = bpf_link_prime(&link->link, &link_primer);
2982 	if (err) {
2983 		kfree(link);
2984 		goto out_put_file;
2985 	}
2986 
2987 	event = perf_file->private_data;
2988 	err = perf_event_set_bpf_prog(event, prog, attr->link_create.perf_event.bpf_cookie);
2989 	if (err) {
2990 		bpf_link_cleanup(&link_primer);
2991 		goto out_put_file;
2992 	}
2993 	/* perf_event_set_bpf_prog() doesn't take its own refcnt on prog */
2994 	bpf_prog_inc(prog);
2995 
2996 	return bpf_link_settle(&link_primer);
2997 
2998 out_put_file:
2999 	fput(perf_file);
3000 	return err;
3001 }
3002 #endif /* CONFIG_PERF_EVENTS */
3003 
3004 #define BPF_RAW_TRACEPOINT_OPEN_LAST_FIELD raw_tracepoint.prog_fd
3005 
3006 static int bpf_raw_tracepoint_open(const union bpf_attr *attr)
3007 {
3008 	struct bpf_link_primer link_primer;
3009 	struct bpf_raw_tp_link *link;
3010 	struct bpf_raw_event_map *btp;
3011 	struct bpf_prog *prog;
3012 	const char *tp_name;
3013 	char buf[128];
3014 	int err;
3015 
3016 	if (CHECK_ATTR(BPF_RAW_TRACEPOINT_OPEN))
3017 		return -EINVAL;
3018 
3019 	prog = bpf_prog_get(attr->raw_tracepoint.prog_fd);
3020 	if (IS_ERR(prog))
3021 		return PTR_ERR(prog);
3022 
3023 	switch (prog->type) {
3024 	case BPF_PROG_TYPE_TRACING:
3025 	case BPF_PROG_TYPE_EXT:
3026 	case BPF_PROG_TYPE_LSM:
3027 		if (attr->raw_tracepoint.name) {
3028 			/* The attach point for this category of programs
3029 			 * should be specified via btf_id during program load.
3030 			 */
3031 			err = -EINVAL;
3032 			goto out_put_prog;
3033 		}
3034 		if (prog->type == BPF_PROG_TYPE_TRACING &&
3035 		    prog->expected_attach_type == BPF_TRACE_RAW_TP) {
3036 			tp_name = prog->aux->attach_func_name;
3037 			break;
3038 		}
3039 		err = bpf_tracing_prog_attach(prog, 0, 0);
3040 		if (err >= 0)
3041 			return err;
3042 		goto out_put_prog;
3043 	case BPF_PROG_TYPE_RAW_TRACEPOINT:
3044 	case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE:
3045 		if (strncpy_from_user(buf,
3046 				      u64_to_user_ptr(attr->raw_tracepoint.name),
3047 				      sizeof(buf) - 1) < 0) {
3048 			err = -EFAULT;
3049 			goto out_put_prog;
3050 		}
3051 		buf[sizeof(buf) - 1] = 0;
3052 		tp_name = buf;
3053 		break;
3054 	default:
3055 		err = -EINVAL;
3056 		goto out_put_prog;
3057 	}
3058 
3059 	btp = bpf_get_raw_tracepoint(tp_name);
3060 	if (!btp) {
3061 		err = -ENOENT;
3062 		goto out_put_prog;
3063 	}
3064 
3065 	link = kzalloc(sizeof(*link), GFP_USER);
3066 	if (!link) {
3067 		err = -ENOMEM;
3068 		goto out_put_btp;
3069 	}
3070 	bpf_link_init(&link->link, BPF_LINK_TYPE_RAW_TRACEPOINT,
3071 		      &bpf_raw_tp_link_lops, prog);
3072 	link->btp = btp;
3073 
3074 	err = bpf_link_prime(&link->link, &link_primer);
3075 	if (err) {
3076 		kfree(link);
3077 		goto out_put_btp;
3078 	}
3079 
3080 	err = bpf_probe_register(link->btp, prog);
3081 	if (err) {
3082 		bpf_link_cleanup(&link_primer);
3083 		goto out_put_btp;
3084 	}
3085 
3086 	return bpf_link_settle(&link_primer);
3087 
3088 out_put_btp:
3089 	bpf_put_raw_tracepoint(btp);
3090 out_put_prog:
3091 	bpf_prog_put(prog);
3092 	return err;
3093 }
3094 
3095 static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog,
3096 					     enum bpf_attach_type attach_type)
3097 {
3098 	switch (prog->type) {
3099 	case BPF_PROG_TYPE_CGROUP_SOCK:
3100 	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
3101 	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
3102 	case BPF_PROG_TYPE_SK_LOOKUP:
3103 		return attach_type == prog->expected_attach_type ? 0 : -EINVAL;
3104 	case BPF_PROG_TYPE_CGROUP_SKB:
3105 		if (!capable(CAP_NET_ADMIN))
3106 			/* cg-skb progs can be loaded by unpriv user.
3107 			 * check permissions at attach time.
3108 			 */
3109 			return -EPERM;
3110 		return prog->enforce_expected_attach_type &&
3111 			prog->expected_attach_type != attach_type ?
3112 			-EINVAL : 0;
3113 	default:
3114 		return 0;
3115 	}
3116 }
3117 
3118 static enum bpf_prog_type
3119 attach_type_to_prog_type(enum bpf_attach_type attach_type)
3120 {
3121 	switch (attach_type) {
3122 	case BPF_CGROUP_INET_INGRESS:
3123 	case BPF_CGROUP_INET_EGRESS:
3124 		return BPF_PROG_TYPE_CGROUP_SKB;
3125 	case BPF_CGROUP_INET_SOCK_CREATE:
3126 	case BPF_CGROUP_INET_SOCK_RELEASE:
3127 	case BPF_CGROUP_INET4_POST_BIND:
3128 	case BPF_CGROUP_INET6_POST_BIND:
3129 		return BPF_PROG_TYPE_CGROUP_SOCK;
3130 	case BPF_CGROUP_INET4_BIND:
3131 	case BPF_CGROUP_INET6_BIND:
3132 	case BPF_CGROUP_INET4_CONNECT:
3133 	case BPF_CGROUP_INET6_CONNECT:
3134 	case BPF_CGROUP_INET4_GETPEERNAME:
3135 	case BPF_CGROUP_INET6_GETPEERNAME:
3136 	case BPF_CGROUP_INET4_GETSOCKNAME:
3137 	case BPF_CGROUP_INET6_GETSOCKNAME:
3138 	case BPF_CGROUP_UDP4_SENDMSG:
3139 	case BPF_CGROUP_UDP6_SENDMSG:
3140 	case BPF_CGROUP_UDP4_RECVMSG:
3141 	case BPF_CGROUP_UDP6_RECVMSG:
3142 		return BPF_PROG_TYPE_CGROUP_SOCK_ADDR;
3143 	case BPF_CGROUP_SOCK_OPS:
3144 		return BPF_PROG_TYPE_SOCK_OPS;
3145 	case BPF_CGROUP_DEVICE:
3146 		return BPF_PROG_TYPE_CGROUP_DEVICE;
3147 	case BPF_SK_MSG_VERDICT:
3148 		return BPF_PROG_TYPE_SK_MSG;
3149 	case BPF_SK_SKB_STREAM_PARSER:
3150 	case BPF_SK_SKB_STREAM_VERDICT:
3151 	case BPF_SK_SKB_VERDICT:
3152 		return BPF_PROG_TYPE_SK_SKB;
3153 	case BPF_LIRC_MODE2:
3154 		return BPF_PROG_TYPE_LIRC_MODE2;
3155 	case BPF_FLOW_DISSECTOR:
3156 		return BPF_PROG_TYPE_FLOW_DISSECTOR;
3157 	case BPF_CGROUP_SYSCTL:
3158 		return BPF_PROG_TYPE_CGROUP_SYSCTL;
3159 	case BPF_CGROUP_GETSOCKOPT:
3160 	case BPF_CGROUP_SETSOCKOPT:
3161 		return BPF_PROG_TYPE_CGROUP_SOCKOPT;
3162 	case BPF_TRACE_ITER:
3163 		return BPF_PROG_TYPE_TRACING;
3164 	case BPF_SK_LOOKUP:
3165 		return BPF_PROG_TYPE_SK_LOOKUP;
3166 	case BPF_XDP:
3167 		return BPF_PROG_TYPE_XDP;
3168 	default:
3169 		return BPF_PROG_TYPE_UNSPEC;
3170 	}
3171 }
3172 
3173 #define BPF_PROG_ATTACH_LAST_FIELD replace_bpf_fd
3174 
3175 #define BPF_F_ATTACH_MASK \
3176 	(BPF_F_ALLOW_OVERRIDE | BPF_F_ALLOW_MULTI | BPF_F_REPLACE)
3177 
3178 static int bpf_prog_attach(const union bpf_attr *attr)
3179 {
3180 	enum bpf_prog_type ptype;
3181 	struct bpf_prog *prog;
3182 	int ret;
3183 
3184 	if (CHECK_ATTR(BPF_PROG_ATTACH))
3185 		return -EINVAL;
3186 
3187 	if (attr->attach_flags & ~BPF_F_ATTACH_MASK)
3188 		return -EINVAL;
3189 
3190 	ptype = attach_type_to_prog_type(attr->attach_type);
3191 	if (ptype == BPF_PROG_TYPE_UNSPEC)
3192 		return -EINVAL;
3193 
3194 	prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype);
3195 	if (IS_ERR(prog))
3196 		return PTR_ERR(prog);
3197 
3198 	if (bpf_prog_attach_check_attach_type(prog, attr->attach_type)) {
3199 		bpf_prog_put(prog);
3200 		return -EINVAL;
3201 	}
3202 
3203 	switch (ptype) {
3204 	case BPF_PROG_TYPE_SK_SKB:
3205 	case BPF_PROG_TYPE_SK_MSG:
3206 		ret = sock_map_get_from_fd(attr, prog);
3207 		break;
3208 	case BPF_PROG_TYPE_LIRC_MODE2:
3209 		ret = lirc_prog_attach(attr, prog);
3210 		break;
3211 	case BPF_PROG_TYPE_FLOW_DISSECTOR:
3212 		ret = netns_bpf_prog_attach(attr, prog);
3213 		break;
3214 	case BPF_PROG_TYPE_CGROUP_DEVICE:
3215 	case BPF_PROG_TYPE_CGROUP_SKB:
3216 	case BPF_PROG_TYPE_CGROUP_SOCK:
3217 	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
3218 	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
3219 	case BPF_PROG_TYPE_CGROUP_SYSCTL:
3220 	case BPF_PROG_TYPE_SOCK_OPS:
3221 		ret = cgroup_bpf_prog_attach(attr, ptype, prog);
3222 		break;
3223 	default:
3224 		ret = -EINVAL;
3225 	}
3226 
3227 	if (ret)
3228 		bpf_prog_put(prog);
3229 	return ret;
3230 }
3231 
3232 #define BPF_PROG_DETACH_LAST_FIELD attach_type
3233 
3234 static int bpf_prog_detach(const union bpf_attr *attr)
3235 {
3236 	enum bpf_prog_type ptype;
3237 
3238 	if (CHECK_ATTR(BPF_PROG_DETACH))
3239 		return -EINVAL;
3240 
3241 	ptype = attach_type_to_prog_type(attr->attach_type);
3242 
3243 	switch (ptype) {
3244 	case BPF_PROG_TYPE_SK_MSG:
3245 	case BPF_PROG_TYPE_SK_SKB:
3246 		return sock_map_prog_detach(attr, ptype);
3247 	case BPF_PROG_TYPE_LIRC_MODE2:
3248 		return lirc_prog_detach(attr);
3249 	case BPF_PROG_TYPE_FLOW_DISSECTOR:
3250 		return netns_bpf_prog_detach(attr, ptype);
3251 	case BPF_PROG_TYPE_CGROUP_DEVICE:
3252 	case BPF_PROG_TYPE_CGROUP_SKB:
3253 	case BPF_PROG_TYPE_CGROUP_SOCK:
3254 	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
3255 	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
3256 	case BPF_PROG_TYPE_CGROUP_SYSCTL:
3257 	case BPF_PROG_TYPE_SOCK_OPS:
3258 		return cgroup_bpf_prog_detach(attr, ptype);
3259 	default:
3260 		return -EINVAL;
3261 	}
3262 }
3263 
3264 #define BPF_PROG_QUERY_LAST_FIELD query.prog_cnt
3265 
3266 static int bpf_prog_query(const union bpf_attr *attr,
3267 			  union bpf_attr __user *uattr)
3268 {
3269 	if (!capable(CAP_NET_ADMIN))
3270 		return -EPERM;
3271 	if (CHECK_ATTR(BPF_PROG_QUERY))
3272 		return -EINVAL;
3273 	if (attr->query.query_flags & ~BPF_F_QUERY_EFFECTIVE)
3274 		return -EINVAL;
3275 
3276 	switch (attr->query.attach_type) {
3277 	case BPF_CGROUP_INET_INGRESS:
3278 	case BPF_CGROUP_INET_EGRESS:
3279 	case BPF_CGROUP_INET_SOCK_CREATE:
3280 	case BPF_CGROUP_INET_SOCK_RELEASE:
3281 	case BPF_CGROUP_INET4_BIND:
3282 	case BPF_CGROUP_INET6_BIND:
3283 	case BPF_CGROUP_INET4_POST_BIND:
3284 	case BPF_CGROUP_INET6_POST_BIND:
3285 	case BPF_CGROUP_INET4_CONNECT:
3286 	case BPF_CGROUP_INET6_CONNECT:
3287 	case BPF_CGROUP_INET4_GETPEERNAME:
3288 	case BPF_CGROUP_INET6_GETPEERNAME:
3289 	case BPF_CGROUP_INET4_GETSOCKNAME:
3290 	case BPF_CGROUP_INET6_GETSOCKNAME:
3291 	case BPF_CGROUP_UDP4_SENDMSG:
3292 	case BPF_CGROUP_UDP6_SENDMSG:
3293 	case BPF_CGROUP_UDP4_RECVMSG:
3294 	case BPF_CGROUP_UDP6_RECVMSG:
3295 	case BPF_CGROUP_SOCK_OPS:
3296 	case BPF_CGROUP_DEVICE:
3297 	case BPF_CGROUP_SYSCTL:
3298 	case BPF_CGROUP_GETSOCKOPT:
3299 	case BPF_CGROUP_SETSOCKOPT:
3300 		return cgroup_bpf_prog_query(attr, uattr);
3301 	case BPF_LIRC_MODE2:
3302 		return lirc_prog_query(attr, uattr);
3303 	case BPF_FLOW_DISSECTOR:
3304 	case BPF_SK_LOOKUP:
3305 		return netns_bpf_prog_query(attr, uattr);
3306 	default:
3307 		return -EINVAL;
3308 	}
3309 }
3310 
3311 #define BPF_PROG_TEST_RUN_LAST_FIELD test.cpu
3312 
3313 static int bpf_prog_test_run(const union bpf_attr *attr,
3314 			     union bpf_attr __user *uattr)
3315 {
3316 	struct bpf_prog *prog;
3317 	int ret = -ENOTSUPP;
3318 
3319 	if (CHECK_ATTR(BPF_PROG_TEST_RUN))
3320 		return -EINVAL;
3321 
3322 	if ((attr->test.ctx_size_in && !attr->test.ctx_in) ||
3323 	    (!attr->test.ctx_size_in && attr->test.ctx_in))
3324 		return -EINVAL;
3325 
3326 	if ((attr->test.ctx_size_out && !attr->test.ctx_out) ||
3327 	    (!attr->test.ctx_size_out && attr->test.ctx_out))
3328 		return -EINVAL;
3329 
3330 	prog = bpf_prog_get(attr->test.prog_fd);
3331 	if (IS_ERR(prog))
3332 		return PTR_ERR(prog);
3333 
3334 	if (prog->aux->ops->test_run)
3335 		ret = prog->aux->ops->test_run(prog, attr, uattr);
3336 
3337 	bpf_prog_put(prog);
3338 	return ret;
3339 }
3340 
3341 #define BPF_OBJ_GET_NEXT_ID_LAST_FIELD next_id
3342 
3343 static int bpf_obj_get_next_id(const union bpf_attr *attr,
3344 			       union bpf_attr __user *uattr,
3345 			       struct idr *idr,
3346 			       spinlock_t *lock)
3347 {
3348 	u32 next_id = attr->start_id;
3349 	int err = 0;
3350 
3351 	if (CHECK_ATTR(BPF_OBJ_GET_NEXT_ID) || next_id >= INT_MAX)
3352 		return -EINVAL;
3353 
3354 	if (!capable(CAP_SYS_ADMIN))
3355 		return -EPERM;
3356 
3357 	next_id++;
3358 	spin_lock_bh(lock);
3359 	if (!idr_get_next(idr, &next_id))
3360 		err = -ENOENT;
3361 	spin_unlock_bh(lock);
3362 
3363 	if (!err)
3364 		err = put_user(next_id, &uattr->next_id);
3365 
3366 	return err;
3367 }
3368 
3369 struct bpf_map *bpf_map_get_curr_or_next(u32 *id)
3370 {
3371 	struct bpf_map *map;
3372 
3373 	spin_lock_bh(&map_idr_lock);
3374 again:
3375 	map = idr_get_next(&map_idr, id);
3376 	if (map) {
3377 		map = __bpf_map_inc_not_zero(map, false);
3378 		if (IS_ERR(map)) {
3379 			(*id)++;
3380 			goto again;
3381 		}
3382 	}
3383 	spin_unlock_bh(&map_idr_lock);
3384 
3385 	return map;
3386 }
3387 
3388 struct bpf_prog *bpf_prog_get_curr_or_next(u32 *id)
3389 {
3390 	struct bpf_prog *prog;
3391 
3392 	spin_lock_bh(&prog_idr_lock);
3393 again:
3394 	prog = idr_get_next(&prog_idr, id);
3395 	if (prog) {
3396 		prog = bpf_prog_inc_not_zero(prog);
3397 		if (IS_ERR(prog)) {
3398 			(*id)++;
3399 			goto again;
3400 		}
3401 	}
3402 	spin_unlock_bh(&prog_idr_lock);
3403 
3404 	return prog;
3405 }
3406 
3407 #define BPF_PROG_GET_FD_BY_ID_LAST_FIELD prog_id
3408 
3409 struct bpf_prog *bpf_prog_by_id(u32 id)
3410 {
3411 	struct bpf_prog *prog;
3412 
3413 	if (!id)
3414 		return ERR_PTR(-ENOENT);
3415 
3416 	spin_lock_bh(&prog_idr_lock);
3417 	prog = idr_find(&prog_idr, id);
3418 	if (prog)
3419 		prog = bpf_prog_inc_not_zero(prog);
3420 	else
3421 		prog = ERR_PTR(-ENOENT);
3422 	spin_unlock_bh(&prog_idr_lock);
3423 	return prog;
3424 }
3425 
3426 static int bpf_prog_get_fd_by_id(const union bpf_attr *attr)
3427 {
3428 	struct bpf_prog *prog;
3429 	u32 id = attr->prog_id;
3430 	int fd;
3431 
3432 	if (CHECK_ATTR(BPF_PROG_GET_FD_BY_ID))
3433 		return -EINVAL;
3434 
3435 	if (!capable(CAP_SYS_ADMIN))
3436 		return -EPERM;
3437 
3438 	prog = bpf_prog_by_id(id);
3439 	if (IS_ERR(prog))
3440 		return PTR_ERR(prog);
3441 
3442 	fd = bpf_prog_new_fd(prog);
3443 	if (fd < 0)
3444 		bpf_prog_put(prog);
3445 
3446 	return fd;
3447 }
3448 
3449 #define BPF_MAP_GET_FD_BY_ID_LAST_FIELD open_flags
3450 
3451 static int bpf_map_get_fd_by_id(const union bpf_attr *attr)
3452 {
3453 	struct bpf_map *map;
3454 	u32 id = attr->map_id;
3455 	int f_flags;
3456 	int fd;
3457 
3458 	if (CHECK_ATTR(BPF_MAP_GET_FD_BY_ID) ||
3459 	    attr->open_flags & ~BPF_OBJ_FLAG_MASK)
3460 		return -EINVAL;
3461 
3462 	if (!capable(CAP_SYS_ADMIN))
3463 		return -EPERM;
3464 
3465 	f_flags = bpf_get_file_flag(attr->open_flags);
3466 	if (f_flags < 0)
3467 		return f_flags;
3468 
3469 	spin_lock_bh(&map_idr_lock);
3470 	map = idr_find(&map_idr, id);
3471 	if (map)
3472 		map = __bpf_map_inc_not_zero(map, true);
3473 	else
3474 		map = ERR_PTR(-ENOENT);
3475 	spin_unlock_bh(&map_idr_lock);
3476 
3477 	if (IS_ERR(map))
3478 		return PTR_ERR(map);
3479 
3480 	fd = bpf_map_new_fd(map, f_flags);
3481 	if (fd < 0)
3482 		bpf_map_put_with_uref(map);
3483 
3484 	return fd;
3485 }
3486 
3487 static const struct bpf_map *bpf_map_from_imm(const struct bpf_prog *prog,
3488 					      unsigned long addr, u32 *off,
3489 					      u32 *type)
3490 {
3491 	const struct bpf_map *map;
3492 	int i;
3493 
3494 	mutex_lock(&prog->aux->used_maps_mutex);
3495 	for (i = 0, *off = 0; i < prog->aux->used_map_cnt; i++) {
3496 		map = prog->aux->used_maps[i];
3497 		if (map == (void *)addr) {
3498 			*type = BPF_PSEUDO_MAP_FD;
3499 			goto out;
3500 		}
3501 		if (!map->ops->map_direct_value_meta)
3502 			continue;
3503 		if (!map->ops->map_direct_value_meta(map, addr, off)) {
3504 			*type = BPF_PSEUDO_MAP_VALUE;
3505 			goto out;
3506 		}
3507 	}
3508 	map = NULL;
3509 
3510 out:
3511 	mutex_unlock(&prog->aux->used_maps_mutex);
3512 	return map;
3513 }
3514 
3515 static struct bpf_insn *bpf_insn_prepare_dump(const struct bpf_prog *prog,
3516 					      const struct cred *f_cred)
3517 {
3518 	const struct bpf_map *map;
3519 	struct bpf_insn *insns;
3520 	u32 off, type;
3521 	u64 imm;
3522 	u8 code;
3523 	int i;
3524 
3525 	insns = kmemdup(prog->insnsi, bpf_prog_insn_size(prog),
3526 			GFP_USER);
3527 	if (!insns)
3528 		return insns;
3529 
3530 	for (i = 0; i < prog->len; i++) {
3531 		code = insns[i].code;
3532 
3533 		if (code == (BPF_JMP | BPF_TAIL_CALL)) {
3534 			insns[i].code = BPF_JMP | BPF_CALL;
3535 			insns[i].imm = BPF_FUNC_tail_call;
3536 			/* fall-through */
3537 		}
3538 		if (code == (BPF_JMP | BPF_CALL) ||
3539 		    code == (BPF_JMP | BPF_CALL_ARGS)) {
3540 			if (code == (BPF_JMP | BPF_CALL_ARGS))
3541 				insns[i].code = BPF_JMP | BPF_CALL;
3542 			if (!bpf_dump_raw_ok(f_cred))
3543 				insns[i].imm = 0;
3544 			continue;
3545 		}
3546 		if (BPF_CLASS(code) == BPF_LDX && BPF_MODE(code) == BPF_PROBE_MEM) {
3547 			insns[i].code = BPF_LDX | BPF_SIZE(code) | BPF_MEM;
3548 			continue;
3549 		}
3550 
3551 		if (code != (BPF_LD | BPF_IMM | BPF_DW))
3552 			continue;
3553 
3554 		imm = ((u64)insns[i + 1].imm << 32) | (u32)insns[i].imm;
3555 		map = bpf_map_from_imm(prog, imm, &off, &type);
3556 		if (map) {
3557 			insns[i].src_reg = type;
3558 			insns[i].imm = map->id;
3559 			insns[i + 1].imm = off;
3560 			continue;
3561 		}
3562 	}
3563 
3564 	return insns;
3565 }
3566 
3567 static int set_info_rec_size(struct bpf_prog_info *info)
3568 {
3569 	/*
3570 	 * Ensure info.*_rec_size is the same as kernel expected size
3571 	 *
3572 	 * or
3573 	 *
3574 	 * Only allow zero *_rec_size if both _rec_size and _cnt are
3575 	 * zero.  In this case, the kernel will set the expected
3576 	 * _rec_size back to the info.
3577 	 */
3578 
3579 	if ((info->nr_func_info || info->func_info_rec_size) &&
3580 	    info->func_info_rec_size != sizeof(struct bpf_func_info))
3581 		return -EINVAL;
3582 
3583 	if ((info->nr_line_info || info->line_info_rec_size) &&
3584 	    info->line_info_rec_size != sizeof(struct bpf_line_info))
3585 		return -EINVAL;
3586 
3587 	if ((info->nr_jited_line_info || info->jited_line_info_rec_size) &&
3588 	    info->jited_line_info_rec_size != sizeof(__u64))
3589 		return -EINVAL;
3590 
3591 	info->func_info_rec_size = sizeof(struct bpf_func_info);
3592 	info->line_info_rec_size = sizeof(struct bpf_line_info);
3593 	info->jited_line_info_rec_size = sizeof(__u64);
3594 
3595 	return 0;
3596 }
3597 
3598 static int bpf_prog_get_info_by_fd(struct file *file,
3599 				   struct bpf_prog *prog,
3600 				   const union bpf_attr *attr,
3601 				   union bpf_attr __user *uattr)
3602 {
3603 	struct bpf_prog_info __user *uinfo = u64_to_user_ptr(attr->info.info);
3604 	struct bpf_prog_info info;
3605 	u32 info_len = attr->info.info_len;
3606 	struct bpf_prog_kstats stats;
3607 	char __user *uinsns;
3608 	u32 ulen;
3609 	int err;
3610 
3611 	err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len);
3612 	if (err)
3613 		return err;
3614 	info_len = min_t(u32, sizeof(info), info_len);
3615 
3616 	memset(&info, 0, sizeof(info));
3617 	if (copy_from_user(&info, uinfo, info_len))
3618 		return -EFAULT;
3619 
3620 	info.type = prog->type;
3621 	info.id = prog->aux->id;
3622 	info.load_time = prog->aux->load_time;
3623 	info.created_by_uid = from_kuid_munged(current_user_ns(),
3624 					       prog->aux->user->uid);
3625 	info.gpl_compatible = prog->gpl_compatible;
3626 
3627 	memcpy(info.tag, prog->tag, sizeof(prog->tag));
3628 	memcpy(info.name, prog->aux->name, sizeof(prog->aux->name));
3629 
3630 	mutex_lock(&prog->aux->used_maps_mutex);
3631 	ulen = info.nr_map_ids;
3632 	info.nr_map_ids = prog->aux->used_map_cnt;
3633 	ulen = min_t(u32, info.nr_map_ids, ulen);
3634 	if (ulen) {
3635 		u32 __user *user_map_ids = u64_to_user_ptr(info.map_ids);
3636 		u32 i;
3637 
3638 		for (i = 0; i < ulen; i++)
3639 			if (put_user(prog->aux->used_maps[i]->id,
3640 				     &user_map_ids[i])) {
3641 				mutex_unlock(&prog->aux->used_maps_mutex);
3642 				return -EFAULT;
3643 			}
3644 	}
3645 	mutex_unlock(&prog->aux->used_maps_mutex);
3646 
3647 	err = set_info_rec_size(&info);
3648 	if (err)
3649 		return err;
3650 
3651 	bpf_prog_get_stats(prog, &stats);
3652 	info.run_time_ns = stats.nsecs;
3653 	info.run_cnt = stats.cnt;
3654 	info.recursion_misses = stats.misses;
3655 
3656 	info.verified_insns = prog->aux->verified_insns;
3657 
3658 	if (!bpf_capable()) {
3659 		info.jited_prog_len = 0;
3660 		info.xlated_prog_len = 0;
3661 		info.nr_jited_ksyms = 0;
3662 		info.nr_jited_func_lens = 0;
3663 		info.nr_func_info = 0;
3664 		info.nr_line_info = 0;
3665 		info.nr_jited_line_info = 0;
3666 		goto done;
3667 	}
3668 
3669 	ulen = info.xlated_prog_len;
3670 	info.xlated_prog_len = bpf_prog_insn_size(prog);
3671 	if (info.xlated_prog_len && ulen) {
3672 		struct bpf_insn *insns_sanitized;
3673 		bool fault;
3674 
3675 		if (prog->blinded && !bpf_dump_raw_ok(file->f_cred)) {
3676 			info.xlated_prog_insns = 0;
3677 			goto done;
3678 		}
3679 		insns_sanitized = bpf_insn_prepare_dump(prog, file->f_cred);
3680 		if (!insns_sanitized)
3681 			return -ENOMEM;
3682 		uinsns = u64_to_user_ptr(info.xlated_prog_insns);
3683 		ulen = min_t(u32, info.xlated_prog_len, ulen);
3684 		fault = copy_to_user(uinsns, insns_sanitized, ulen);
3685 		kfree(insns_sanitized);
3686 		if (fault)
3687 			return -EFAULT;
3688 	}
3689 
3690 	if (bpf_prog_is_dev_bound(prog->aux)) {
3691 		err = bpf_prog_offload_info_fill(&info, prog);
3692 		if (err)
3693 			return err;
3694 		goto done;
3695 	}
3696 
3697 	/* NOTE: the following code is supposed to be skipped for offload.
3698 	 * bpf_prog_offload_info_fill() is the place to fill similar fields
3699 	 * for offload.
3700 	 */
3701 	ulen = info.jited_prog_len;
3702 	if (prog->aux->func_cnt) {
3703 		u32 i;
3704 
3705 		info.jited_prog_len = 0;
3706 		for (i = 0; i < prog->aux->func_cnt; i++)
3707 			info.jited_prog_len += prog->aux->func[i]->jited_len;
3708 	} else {
3709 		info.jited_prog_len = prog->jited_len;
3710 	}
3711 
3712 	if (info.jited_prog_len && ulen) {
3713 		if (bpf_dump_raw_ok(file->f_cred)) {
3714 			uinsns = u64_to_user_ptr(info.jited_prog_insns);
3715 			ulen = min_t(u32, info.jited_prog_len, ulen);
3716 
3717 			/* for multi-function programs, copy the JITed
3718 			 * instructions for all the functions
3719 			 */
3720 			if (prog->aux->func_cnt) {
3721 				u32 len, free, i;
3722 				u8 *img;
3723 
3724 				free = ulen;
3725 				for (i = 0; i < prog->aux->func_cnt; i++) {
3726 					len = prog->aux->func[i]->jited_len;
3727 					len = min_t(u32, len, free);
3728 					img = (u8 *) prog->aux->func[i]->bpf_func;
3729 					if (copy_to_user(uinsns, img, len))
3730 						return -EFAULT;
3731 					uinsns += len;
3732 					free -= len;
3733 					if (!free)
3734 						break;
3735 				}
3736 			} else {
3737 				if (copy_to_user(uinsns, prog->bpf_func, ulen))
3738 					return -EFAULT;
3739 			}
3740 		} else {
3741 			info.jited_prog_insns = 0;
3742 		}
3743 	}
3744 
3745 	ulen = info.nr_jited_ksyms;
3746 	info.nr_jited_ksyms = prog->aux->func_cnt ? : 1;
3747 	if (ulen) {
3748 		if (bpf_dump_raw_ok(file->f_cred)) {
3749 			unsigned long ksym_addr;
3750 			u64 __user *user_ksyms;
3751 			u32 i;
3752 
3753 			/* copy the address of the kernel symbol
3754 			 * corresponding to each function
3755 			 */
3756 			ulen = min_t(u32, info.nr_jited_ksyms, ulen);
3757 			user_ksyms = u64_to_user_ptr(info.jited_ksyms);
3758 			if (prog->aux->func_cnt) {
3759 				for (i = 0; i < ulen; i++) {
3760 					ksym_addr = (unsigned long)
3761 						prog->aux->func[i]->bpf_func;
3762 					if (put_user((u64) ksym_addr,
3763 						     &user_ksyms[i]))
3764 						return -EFAULT;
3765 				}
3766 			} else {
3767 				ksym_addr = (unsigned long) prog->bpf_func;
3768 				if (put_user((u64) ksym_addr, &user_ksyms[0]))
3769 					return -EFAULT;
3770 			}
3771 		} else {
3772 			info.jited_ksyms = 0;
3773 		}
3774 	}
3775 
3776 	ulen = info.nr_jited_func_lens;
3777 	info.nr_jited_func_lens = prog->aux->func_cnt ? : 1;
3778 	if (ulen) {
3779 		if (bpf_dump_raw_ok(file->f_cred)) {
3780 			u32 __user *user_lens;
3781 			u32 func_len, i;
3782 
3783 			/* copy the JITed image lengths for each function */
3784 			ulen = min_t(u32, info.nr_jited_func_lens, ulen);
3785 			user_lens = u64_to_user_ptr(info.jited_func_lens);
3786 			if (prog->aux->func_cnt) {
3787 				for (i = 0; i < ulen; i++) {
3788 					func_len =
3789 						prog->aux->func[i]->jited_len;
3790 					if (put_user(func_len, &user_lens[i]))
3791 						return -EFAULT;
3792 				}
3793 			} else {
3794 				func_len = prog->jited_len;
3795 				if (put_user(func_len, &user_lens[0]))
3796 					return -EFAULT;
3797 			}
3798 		} else {
3799 			info.jited_func_lens = 0;
3800 		}
3801 	}
3802 
3803 	if (prog->aux->btf)
3804 		info.btf_id = btf_obj_id(prog->aux->btf);
3805 
3806 	ulen = info.nr_func_info;
3807 	info.nr_func_info = prog->aux->func_info_cnt;
3808 	if (info.nr_func_info && ulen) {
3809 		char __user *user_finfo;
3810 
3811 		user_finfo = u64_to_user_ptr(info.func_info);
3812 		ulen = min_t(u32, info.nr_func_info, ulen);
3813 		if (copy_to_user(user_finfo, prog->aux->func_info,
3814 				 info.func_info_rec_size * ulen))
3815 			return -EFAULT;
3816 	}
3817 
3818 	ulen = info.nr_line_info;
3819 	info.nr_line_info = prog->aux->nr_linfo;
3820 	if (info.nr_line_info && ulen) {
3821 		__u8 __user *user_linfo;
3822 
3823 		user_linfo = u64_to_user_ptr(info.line_info);
3824 		ulen = min_t(u32, info.nr_line_info, ulen);
3825 		if (copy_to_user(user_linfo, prog->aux->linfo,
3826 				 info.line_info_rec_size * ulen))
3827 			return -EFAULT;
3828 	}
3829 
3830 	ulen = info.nr_jited_line_info;
3831 	if (prog->aux->jited_linfo)
3832 		info.nr_jited_line_info = prog->aux->nr_linfo;
3833 	else
3834 		info.nr_jited_line_info = 0;
3835 	if (info.nr_jited_line_info && ulen) {
3836 		if (bpf_dump_raw_ok(file->f_cred)) {
3837 			__u64 __user *user_linfo;
3838 			u32 i;
3839 
3840 			user_linfo = u64_to_user_ptr(info.jited_line_info);
3841 			ulen = min_t(u32, info.nr_jited_line_info, ulen);
3842 			for (i = 0; i < ulen; i++) {
3843 				if (put_user((__u64)(long)prog->aux->jited_linfo[i],
3844 					     &user_linfo[i]))
3845 					return -EFAULT;
3846 			}
3847 		} else {
3848 			info.jited_line_info = 0;
3849 		}
3850 	}
3851 
3852 	ulen = info.nr_prog_tags;
3853 	info.nr_prog_tags = prog->aux->func_cnt ? : 1;
3854 	if (ulen) {
3855 		__u8 __user (*user_prog_tags)[BPF_TAG_SIZE];
3856 		u32 i;
3857 
3858 		user_prog_tags = u64_to_user_ptr(info.prog_tags);
3859 		ulen = min_t(u32, info.nr_prog_tags, ulen);
3860 		if (prog->aux->func_cnt) {
3861 			for (i = 0; i < ulen; i++) {
3862 				if (copy_to_user(user_prog_tags[i],
3863 						 prog->aux->func[i]->tag,
3864 						 BPF_TAG_SIZE))
3865 					return -EFAULT;
3866 			}
3867 		} else {
3868 			if (copy_to_user(user_prog_tags[0],
3869 					 prog->tag, BPF_TAG_SIZE))
3870 				return -EFAULT;
3871 		}
3872 	}
3873 
3874 done:
3875 	if (copy_to_user(uinfo, &info, info_len) ||
3876 	    put_user(info_len, &uattr->info.info_len))
3877 		return -EFAULT;
3878 
3879 	return 0;
3880 }
3881 
3882 static int bpf_map_get_info_by_fd(struct file *file,
3883 				  struct bpf_map *map,
3884 				  const union bpf_attr *attr,
3885 				  union bpf_attr __user *uattr)
3886 {
3887 	struct bpf_map_info __user *uinfo = u64_to_user_ptr(attr->info.info);
3888 	struct bpf_map_info info;
3889 	u32 info_len = attr->info.info_len;
3890 	int err;
3891 
3892 	err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len);
3893 	if (err)
3894 		return err;
3895 	info_len = min_t(u32, sizeof(info), info_len);
3896 
3897 	memset(&info, 0, sizeof(info));
3898 	info.type = map->map_type;
3899 	info.id = map->id;
3900 	info.key_size = map->key_size;
3901 	info.value_size = map->value_size;
3902 	info.max_entries = map->max_entries;
3903 	info.map_flags = map->map_flags;
3904 	info.map_extra = map->map_extra;
3905 	memcpy(info.name, map->name, sizeof(map->name));
3906 
3907 	if (map->btf) {
3908 		info.btf_id = btf_obj_id(map->btf);
3909 		info.btf_key_type_id = map->btf_key_type_id;
3910 		info.btf_value_type_id = map->btf_value_type_id;
3911 	}
3912 	info.btf_vmlinux_value_type_id = map->btf_vmlinux_value_type_id;
3913 
3914 	if (bpf_map_is_dev_bound(map)) {
3915 		err = bpf_map_offload_info_fill(&info, map);
3916 		if (err)
3917 			return err;
3918 	}
3919 
3920 	if (copy_to_user(uinfo, &info, info_len) ||
3921 	    put_user(info_len, &uattr->info.info_len))
3922 		return -EFAULT;
3923 
3924 	return 0;
3925 }
3926 
3927 static int bpf_btf_get_info_by_fd(struct file *file,
3928 				  struct btf *btf,
3929 				  const union bpf_attr *attr,
3930 				  union bpf_attr __user *uattr)
3931 {
3932 	struct bpf_btf_info __user *uinfo = u64_to_user_ptr(attr->info.info);
3933 	u32 info_len = attr->info.info_len;
3934 	int err;
3935 
3936 	err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(*uinfo), info_len);
3937 	if (err)
3938 		return err;
3939 
3940 	return btf_get_info_by_fd(btf, attr, uattr);
3941 }
3942 
3943 static int bpf_link_get_info_by_fd(struct file *file,
3944 				  struct bpf_link *link,
3945 				  const union bpf_attr *attr,
3946 				  union bpf_attr __user *uattr)
3947 {
3948 	struct bpf_link_info __user *uinfo = u64_to_user_ptr(attr->info.info);
3949 	struct bpf_link_info info;
3950 	u32 info_len = attr->info.info_len;
3951 	int err;
3952 
3953 	err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len);
3954 	if (err)
3955 		return err;
3956 	info_len = min_t(u32, sizeof(info), info_len);
3957 
3958 	memset(&info, 0, sizeof(info));
3959 	if (copy_from_user(&info, uinfo, info_len))
3960 		return -EFAULT;
3961 
3962 	info.type = link->type;
3963 	info.id = link->id;
3964 	info.prog_id = link->prog->aux->id;
3965 
3966 	if (link->ops->fill_link_info) {
3967 		err = link->ops->fill_link_info(link, &info);
3968 		if (err)
3969 			return err;
3970 	}
3971 
3972 	if (copy_to_user(uinfo, &info, info_len) ||
3973 	    put_user(info_len, &uattr->info.info_len))
3974 		return -EFAULT;
3975 
3976 	return 0;
3977 }
3978 
3979 
3980 #define BPF_OBJ_GET_INFO_BY_FD_LAST_FIELD info.info
3981 
3982 static int bpf_obj_get_info_by_fd(const union bpf_attr *attr,
3983 				  union bpf_attr __user *uattr)
3984 {
3985 	int ufd = attr->info.bpf_fd;
3986 	struct fd f;
3987 	int err;
3988 
3989 	if (CHECK_ATTR(BPF_OBJ_GET_INFO_BY_FD))
3990 		return -EINVAL;
3991 
3992 	f = fdget(ufd);
3993 	if (!f.file)
3994 		return -EBADFD;
3995 
3996 	if (f.file->f_op == &bpf_prog_fops)
3997 		err = bpf_prog_get_info_by_fd(f.file, f.file->private_data, attr,
3998 					      uattr);
3999 	else if (f.file->f_op == &bpf_map_fops)
4000 		err = bpf_map_get_info_by_fd(f.file, f.file->private_data, attr,
4001 					     uattr);
4002 	else if (f.file->f_op == &btf_fops)
4003 		err = bpf_btf_get_info_by_fd(f.file, f.file->private_data, attr, uattr);
4004 	else if (f.file->f_op == &bpf_link_fops)
4005 		err = bpf_link_get_info_by_fd(f.file, f.file->private_data,
4006 					      attr, uattr);
4007 	else
4008 		err = -EINVAL;
4009 
4010 	fdput(f);
4011 	return err;
4012 }
4013 
4014 #define BPF_BTF_LOAD_LAST_FIELD btf_log_level
4015 
4016 static int bpf_btf_load(const union bpf_attr *attr, bpfptr_t uattr)
4017 {
4018 	if (CHECK_ATTR(BPF_BTF_LOAD))
4019 		return -EINVAL;
4020 
4021 	if (!bpf_capable())
4022 		return -EPERM;
4023 
4024 	return btf_new_fd(attr, uattr);
4025 }
4026 
4027 #define BPF_BTF_GET_FD_BY_ID_LAST_FIELD btf_id
4028 
4029 static int bpf_btf_get_fd_by_id(const union bpf_attr *attr)
4030 {
4031 	if (CHECK_ATTR(BPF_BTF_GET_FD_BY_ID))
4032 		return -EINVAL;
4033 
4034 	if (!capable(CAP_SYS_ADMIN))
4035 		return -EPERM;
4036 
4037 	return btf_get_fd_by_id(attr->btf_id);
4038 }
4039 
4040 static int bpf_task_fd_query_copy(const union bpf_attr *attr,
4041 				    union bpf_attr __user *uattr,
4042 				    u32 prog_id, u32 fd_type,
4043 				    const char *buf, u64 probe_offset,
4044 				    u64 probe_addr)
4045 {
4046 	char __user *ubuf = u64_to_user_ptr(attr->task_fd_query.buf);
4047 	u32 len = buf ? strlen(buf) : 0, input_len;
4048 	int err = 0;
4049 
4050 	if (put_user(len, &uattr->task_fd_query.buf_len))
4051 		return -EFAULT;
4052 	input_len = attr->task_fd_query.buf_len;
4053 	if (input_len && ubuf) {
4054 		if (!len) {
4055 			/* nothing to copy, just make ubuf NULL terminated */
4056 			char zero = '\0';
4057 
4058 			if (put_user(zero, ubuf))
4059 				return -EFAULT;
4060 		} else if (input_len >= len + 1) {
4061 			/* ubuf can hold the string with NULL terminator */
4062 			if (copy_to_user(ubuf, buf, len + 1))
4063 				return -EFAULT;
4064 		} else {
4065 			/* ubuf cannot hold the string with NULL terminator,
4066 			 * do a partial copy with NULL terminator.
4067 			 */
4068 			char zero = '\0';
4069 
4070 			err = -ENOSPC;
4071 			if (copy_to_user(ubuf, buf, input_len - 1))
4072 				return -EFAULT;
4073 			if (put_user(zero, ubuf + input_len - 1))
4074 				return -EFAULT;
4075 		}
4076 	}
4077 
4078 	if (put_user(prog_id, &uattr->task_fd_query.prog_id) ||
4079 	    put_user(fd_type, &uattr->task_fd_query.fd_type) ||
4080 	    put_user(probe_offset, &uattr->task_fd_query.probe_offset) ||
4081 	    put_user(probe_addr, &uattr->task_fd_query.probe_addr))
4082 		return -EFAULT;
4083 
4084 	return err;
4085 }
4086 
4087 #define BPF_TASK_FD_QUERY_LAST_FIELD task_fd_query.probe_addr
4088 
4089 static int bpf_task_fd_query(const union bpf_attr *attr,
4090 			     union bpf_attr __user *uattr)
4091 {
4092 	pid_t pid = attr->task_fd_query.pid;
4093 	u32 fd = attr->task_fd_query.fd;
4094 	const struct perf_event *event;
4095 	struct task_struct *task;
4096 	struct file *file;
4097 	int err;
4098 
4099 	if (CHECK_ATTR(BPF_TASK_FD_QUERY))
4100 		return -EINVAL;
4101 
4102 	if (!capable(CAP_SYS_ADMIN))
4103 		return -EPERM;
4104 
4105 	if (attr->task_fd_query.flags != 0)
4106 		return -EINVAL;
4107 
4108 	task = get_pid_task(find_vpid(pid), PIDTYPE_PID);
4109 	if (!task)
4110 		return -ENOENT;
4111 
4112 	err = 0;
4113 	file = fget_task(task, fd);
4114 	put_task_struct(task);
4115 	if (!file)
4116 		return -EBADF;
4117 
4118 	if (file->f_op == &bpf_link_fops) {
4119 		struct bpf_link *link = file->private_data;
4120 
4121 		if (link->ops == &bpf_raw_tp_link_lops) {
4122 			struct bpf_raw_tp_link *raw_tp =
4123 				container_of(link, struct bpf_raw_tp_link, link);
4124 			struct bpf_raw_event_map *btp = raw_tp->btp;
4125 
4126 			err = bpf_task_fd_query_copy(attr, uattr,
4127 						     raw_tp->link.prog->aux->id,
4128 						     BPF_FD_TYPE_RAW_TRACEPOINT,
4129 						     btp->tp->name, 0, 0);
4130 			goto put_file;
4131 		}
4132 		goto out_not_supp;
4133 	}
4134 
4135 	event = perf_get_event(file);
4136 	if (!IS_ERR(event)) {
4137 		u64 probe_offset, probe_addr;
4138 		u32 prog_id, fd_type;
4139 		const char *buf;
4140 
4141 		err = bpf_get_perf_event_info(event, &prog_id, &fd_type,
4142 					      &buf, &probe_offset,
4143 					      &probe_addr);
4144 		if (!err)
4145 			err = bpf_task_fd_query_copy(attr, uattr, prog_id,
4146 						     fd_type, buf,
4147 						     probe_offset,
4148 						     probe_addr);
4149 		goto put_file;
4150 	}
4151 
4152 out_not_supp:
4153 	err = -ENOTSUPP;
4154 put_file:
4155 	fput(file);
4156 	return err;
4157 }
4158 
4159 #define BPF_MAP_BATCH_LAST_FIELD batch.flags
4160 
4161 #define BPF_DO_BATCH(fn)			\
4162 	do {					\
4163 		if (!fn) {			\
4164 			err = -ENOTSUPP;	\
4165 			goto err_put;		\
4166 		}				\
4167 		err = fn(map, attr, uattr);	\
4168 	} while (0)
4169 
4170 static int bpf_map_do_batch(const union bpf_attr *attr,
4171 			    union bpf_attr __user *uattr,
4172 			    int cmd)
4173 {
4174 	struct bpf_map *map;
4175 	int err, ufd;
4176 	struct fd f;
4177 
4178 	if (CHECK_ATTR(BPF_MAP_BATCH))
4179 		return -EINVAL;
4180 
4181 	ufd = attr->batch.map_fd;
4182 	f = fdget(ufd);
4183 	map = __bpf_map_get(f);
4184 	if (IS_ERR(map))
4185 		return PTR_ERR(map);
4186 
4187 	if ((cmd == BPF_MAP_LOOKUP_BATCH ||
4188 	     cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH) &&
4189 	    !(map_get_sys_perms(map, f) & FMODE_CAN_READ)) {
4190 		err = -EPERM;
4191 		goto err_put;
4192 	}
4193 
4194 	if (cmd != BPF_MAP_LOOKUP_BATCH &&
4195 	    !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
4196 		err = -EPERM;
4197 		goto err_put;
4198 	}
4199 
4200 	if (cmd == BPF_MAP_LOOKUP_BATCH)
4201 		BPF_DO_BATCH(map->ops->map_lookup_batch);
4202 	else if (cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH)
4203 		BPF_DO_BATCH(map->ops->map_lookup_and_delete_batch);
4204 	else if (cmd == BPF_MAP_UPDATE_BATCH)
4205 		BPF_DO_BATCH(map->ops->map_update_batch);
4206 	else
4207 		BPF_DO_BATCH(map->ops->map_delete_batch);
4208 
4209 err_put:
4210 	fdput(f);
4211 	return err;
4212 }
4213 
4214 static int tracing_bpf_link_attach(const union bpf_attr *attr, bpfptr_t uattr,
4215 				   struct bpf_prog *prog)
4216 {
4217 	if (attr->link_create.attach_type != prog->expected_attach_type)
4218 		return -EINVAL;
4219 
4220 	if (prog->expected_attach_type == BPF_TRACE_ITER)
4221 		return bpf_iter_link_attach(attr, uattr, prog);
4222 	else if (prog->type == BPF_PROG_TYPE_EXT)
4223 		return bpf_tracing_prog_attach(prog,
4224 					       attr->link_create.target_fd,
4225 					       attr->link_create.target_btf_id);
4226 	return -EINVAL;
4227 }
4228 
4229 #define BPF_LINK_CREATE_LAST_FIELD link_create.iter_info_len
4230 static int link_create(union bpf_attr *attr, bpfptr_t uattr)
4231 {
4232 	enum bpf_prog_type ptype;
4233 	struct bpf_prog *prog;
4234 	int ret;
4235 
4236 	if (CHECK_ATTR(BPF_LINK_CREATE))
4237 		return -EINVAL;
4238 
4239 	prog = bpf_prog_get(attr->link_create.prog_fd);
4240 	if (IS_ERR(prog))
4241 		return PTR_ERR(prog);
4242 
4243 	ret = bpf_prog_attach_check_attach_type(prog,
4244 						attr->link_create.attach_type);
4245 	if (ret)
4246 		goto out;
4247 
4248 	switch (prog->type) {
4249 	case BPF_PROG_TYPE_EXT:
4250 		ret = tracing_bpf_link_attach(attr, uattr, prog);
4251 		goto out;
4252 	case BPF_PROG_TYPE_PERF_EVENT:
4253 	case BPF_PROG_TYPE_KPROBE:
4254 	case BPF_PROG_TYPE_TRACEPOINT:
4255 		if (attr->link_create.attach_type != BPF_PERF_EVENT) {
4256 			ret = -EINVAL;
4257 			goto out;
4258 		}
4259 		ptype = prog->type;
4260 		break;
4261 	default:
4262 		ptype = attach_type_to_prog_type(attr->link_create.attach_type);
4263 		if (ptype == BPF_PROG_TYPE_UNSPEC || ptype != prog->type) {
4264 			ret = -EINVAL;
4265 			goto out;
4266 		}
4267 		break;
4268 	}
4269 
4270 	switch (ptype) {
4271 	case BPF_PROG_TYPE_CGROUP_SKB:
4272 	case BPF_PROG_TYPE_CGROUP_SOCK:
4273 	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
4274 	case BPF_PROG_TYPE_SOCK_OPS:
4275 	case BPF_PROG_TYPE_CGROUP_DEVICE:
4276 	case BPF_PROG_TYPE_CGROUP_SYSCTL:
4277 	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
4278 		ret = cgroup_bpf_link_attach(attr, prog);
4279 		break;
4280 	case BPF_PROG_TYPE_TRACING:
4281 		ret = tracing_bpf_link_attach(attr, uattr, prog);
4282 		break;
4283 	case BPF_PROG_TYPE_FLOW_DISSECTOR:
4284 	case BPF_PROG_TYPE_SK_LOOKUP:
4285 		ret = netns_bpf_link_create(attr, prog);
4286 		break;
4287 #ifdef CONFIG_NET
4288 	case BPF_PROG_TYPE_XDP:
4289 		ret = bpf_xdp_link_attach(attr, prog);
4290 		break;
4291 #endif
4292 #ifdef CONFIG_PERF_EVENTS
4293 	case BPF_PROG_TYPE_PERF_EVENT:
4294 	case BPF_PROG_TYPE_TRACEPOINT:
4295 	case BPF_PROG_TYPE_KPROBE:
4296 		ret = bpf_perf_link_attach(attr, prog);
4297 		break;
4298 #endif
4299 	default:
4300 		ret = -EINVAL;
4301 	}
4302 
4303 out:
4304 	if (ret < 0)
4305 		bpf_prog_put(prog);
4306 	return ret;
4307 }
4308 
4309 #define BPF_LINK_UPDATE_LAST_FIELD link_update.old_prog_fd
4310 
4311 static int link_update(union bpf_attr *attr)
4312 {
4313 	struct bpf_prog *old_prog = NULL, *new_prog;
4314 	struct bpf_link *link;
4315 	u32 flags;
4316 	int ret;
4317 
4318 	if (CHECK_ATTR(BPF_LINK_UPDATE))
4319 		return -EINVAL;
4320 
4321 	flags = attr->link_update.flags;
4322 	if (flags & ~BPF_F_REPLACE)
4323 		return -EINVAL;
4324 
4325 	link = bpf_link_get_from_fd(attr->link_update.link_fd);
4326 	if (IS_ERR(link))
4327 		return PTR_ERR(link);
4328 
4329 	new_prog = bpf_prog_get(attr->link_update.new_prog_fd);
4330 	if (IS_ERR(new_prog)) {
4331 		ret = PTR_ERR(new_prog);
4332 		goto out_put_link;
4333 	}
4334 
4335 	if (flags & BPF_F_REPLACE) {
4336 		old_prog = bpf_prog_get(attr->link_update.old_prog_fd);
4337 		if (IS_ERR(old_prog)) {
4338 			ret = PTR_ERR(old_prog);
4339 			old_prog = NULL;
4340 			goto out_put_progs;
4341 		}
4342 	} else if (attr->link_update.old_prog_fd) {
4343 		ret = -EINVAL;
4344 		goto out_put_progs;
4345 	}
4346 
4347 	if (link->ops->update_prog)
4348 		ret = link->ops->update_prog(link, new_prog, old_prog);
4349 	else
4350 		ret = -EINVAL;
4351 
4352 out_put_progs:
4353 	if (old_prog)
4354 		bpf_prog_put(old_prog);
4355 	if (ret)
4356 		bpf_prog_put(new_prog);
4357 out_put_link:
4358 	bpf_link_put(link);
4359 	return ret;
4360 }
4361 
4362 #define BPF_LINK_DETACH_LAST_FIELD link_detach.link_fd
4363 
4364 static int link_detach(union bpf_attr *attr)
4365 {
4366 	struct bpf_link *link;
4367 	int ret;
4368 
4369 	if (CHECK_ATTR(BPF_LINK_DETACH))
4370 		return -EINVAL;
4371 
4372 	link = bpf_link_get_from_fd(attr->link_detach.link_fd);
4373 	if (IS_ERR(link))
4374 		return PTR_ERR(link);
4375 
4376 	if (link->ops->detach)
4377 		ret = link->ops->detach(link);
4378 	else
4379 		ret = -EOPNOTSUPP;
4380 
4381 	bpf_link_put(link);
4382 	return ret;
4383 }
4384 
4385 static struct bpf_link *bpf_link_inc_not_zero(struct bpf_link *link)
4386 {
4387 	return atomic64_fetch_add_unless(&link->refcnt, 1, 0) ? link : ERR_PTR(-ENOENT);
4388 }
4389 
4390 struct bpf_link *bpf_link_by_id(u32 id)
4391 {
4392 	struct bpf_link *link;
4393 
4394 	if (!id)
4395 		return ERR_PTR(-ENOENT);
4396 
4397 	spin_lock_bh(&link_idr_lock);
4398 	/* before link is "settled", ID is 0, pretend it doesn't exist yet */
4399 	link = idr_find(&link_idr, id);
4400 	if (link) {
4401 		if (link->id)
4402 			link = bpf_link_inc_not_zero(link);
4403 		else
4404 			link = ERR_PTR(-EAGAIN);
4405 	} else {
4406 		link = ERR_PTR(-ENOENT);
4407 	}
4408 	spin_unlock_bh(&link_idr_lock);
4409 	return link;
4410 }
4411 
4412 #define BPF_LINK_GET_FD_BY_ID_LAST_FIELD link_id
4413 
4414 static int bpf_link_get_fd_by_id(const union bpf_attr *attr)
4415 {
4416 	struct bpf_link *link;
4417 	u32 id = attr->link_id;
4418 	int fd;
4419 
4420 	if (CHECK_ATTR(BPF_LINK_GET_FD_BY_ID))
4421 		return -EINVAL;
4422 
4423 	if (!capable(CAP_SYS_ADMIN))
4424 		return -EPERM;
4425 
4426 	link = bpf_link_by_id(id);
4427 	if (IS_ERR(link))
4428 		return PTR_ERR(link);
4429 
4430 	fd = bpf_link_new_fd(link);
4431 	if (fd < 0)
4432 		bpf_link_put(link);
4433 
4434 	return fd;
4435 }
4436 
4437 DEFINE_MUTEX(bpf_stats_enabled_mutex);
4438 
4439 static int bpf_stats_release(struct inode *inode, struct file *file)
4440 {
4441 	mutex_lock(&bpf_stats_enabled_mutex);
4442 	static_key_slow_dec(&bpf_stats_enabled_key.key);
4443 	mutex_unlock(&bpf_stats_enabled_mutex);
4444 	return 0;
4445 }
4446 
4447 static const struct file_operations bpf_stats_fops = {
4448 	.release = bpf_stats_release,
4449 };
4450 
4451 static int bpf_enable_runtime_stats(void)
4452 {
4453 	int fd;
4454 
4455 	mutex_lock(&bpf_stats_enabled_mutex);
4456 
4457 	/* Set a very high limit to avoid overflow */
4458 	if (static_key_count(&bpf_stats_enabled_key.key) > INT_MAX / 2) {
4459 		mutex_unlock(&bpf_stats_enabled_mutex);
4460 		return -EBUSY;
4461 	}
4462 
4463 	fd = anon_inode_getfd("bpf-stats", &bpf_stats_fops, NULL, O_CLOEXEC);
4464 	if (fd >= 0)
4465 		static_key_slow_inc(&bpf_stats_enabled_key.key);
4466 
4467 	mutex_unlock(&bpf_stats_enabled_mutex);
4468 	return fd;
4469 }
4470 
4471 #define BPF_ENABLE_STATS_LAST_FIELD enable_stats.type
4472 
4473 static int bpf_enable_stats(union bpf_attr *attr)
4474 {
4475 
4476 	if (CHECK_ATTR(BPF_ENABLE_STATS))
4477 		return -EINVAL;
4478 
4479 	if (!capable(CAP_SYS_ADMIN))
4480 		return -EPERM;
4481 
4482 	switch (attr->enable_stats.type) {
4483 	case BPF_STATS_RUN_TIME:
4484 		return bpf_enable_runtime_stats();
4485 	default:
4486 		break;
4487 	}
4488 	return -EINVAL;
4489 }
4490 
4491 #define BPF_ITER_CREATE_LAST_FIELD iter_create.flags
4492 
4493 static int bpf_iter_create(union bpf_attr *attr)
4494 {
4495 	struct bpf_link *link;
4496 	int err;
4497 
4498 	if (CHECK_ATTR(BPF_ITER_CREATE))
4499 		return -EINVAL;
4500 
4501 	if (attr->iter_create.flags)
4502 		return -EINVAL;
4503 
4504 	link = bpf_link_get_from_fd(attr->iter_create.link_fd);
4505 	if (IS_ERR(link))
4506 		return PTR_ERR(link);
4507 
4508 	err = bpf_iter_new_fd(link);
4509 	bpf_link_put(link);
4510 
4511 	return err;
4512 }
4513 
4514 #define BPF_PROG_BIND_MAP_LAST_FIELD prog_bind_map.flags
4515 
4516 static int bpf_prog_bind_map(union bpf_attr *attr)
4517 {
4518 	struct bpf_prog *prog;
4519 	struct bpf_map *map;
4520 	struct bpf_map **used_maps_old, **used_maps_new;
4521 	int i, ret = 0;
4522 
4523 	if (CHECK_ATTR(BPF_PROG_BIND_MAP))
4524 		return -EINVAL;
4525 
4526 	if (attr->prog_bind_map.flags)
4527 		return -EINVAL;
4528 
4529 	prog = bpf_prog_get(attr->prog_bind_map.prog_fd);
4530 	if (IS_ERR(prog))
4531 		return PTR_ERR(prog);
4532 
4533 	map = bpf_map_get(attr->prog_bind_map.map_fd);
4534 	if (IS_ERR(map)) {
4535 		ret = PTR_ERR(map);
4536 		goto out_prog_put;
4537 	}
4538 
4539 	mutex_lock(&prog->aux->used_maps_mutex);
4540 
4541 	used_maps_old = prog->aux->used_maps;
4542 
4543 	for (i = 0; i < prog->aux->used_map_cnt; i++)
4544 		if (used_maps_old[i] == map) {
4545 			bpf_map_put(map);
4546 			goto out_unlock;
4547 		}
4548 
4549 	used_maps_new = kmalloc_array(prog->aux->used_map_cnt + 1,
4550 				      sizeof(used_maps_new[0]),
4551 				      GFP_KERNEL);
4552 	if (!used_maps_new) {
4553 		ret = -ENOMEM;
4554 		goto out_unlock;
4555 	}
4556 
4557 	memcpy(used_maps_new, used_maps_old,
4558 	       sizeof(used_maps_old[0]) * prog->aux->used_map_cnt);
4559 	used_maps_new[prog->aux->used_map_cnt] = map;
4560 
4561 	prog->aux->used_map_cnt++;
4562 	prog->aux->used_maps = used_maps_new;
4563 
4564 	kfree(used_maps_old);
4565 
4566 out_unlock:
4567 	mutex_unlock(&prog->aux->used_maps_mutex);
4568 
4569 	if (ret)
4570 		bpf_map_put(map);
4571 out_prog_put:
4572 	bpf_prog_put(prog);
4573 	return ret;
4574 }
4575 
4576 static int __sys_bpf(int cmd, bpfptr_t uattr, unsigned int size)
4577 {
4578 	union bpf_attr attr;
4579 	int err;
4580 
4581 	if (sysctl_unprivileged_bpf_disabled && !bpf_capable())
4582 		return -EPERM;
4583 
4584 	err = bpf_check_uarg_tail_zero(uattr, sizeof(attr), size);
4585 	if (err)
4586 		return err;
4587 	size = min_t(u32, size, sizeof(attr));
4588 
4589 	/* copy attributes from user space, may be less than sizeof(bpf_attr) */
4590 	memset(&attr, 0, sizeof(attr));
4591 	if (copy_from_bpfptr(&attr, uattr, size) != 0)
4592 		return -EFAULT;
4593 
4594 	err = security_bpf(cmd, &attr, size);
4595 	if (err < 0)
4596 		return err;
4597 
4598 	switch (cmd) {
4599 	case BPF_MAP_CREATE:
4600 		err = map_create(&attr);
4601 		break;
4602 	case BPF_MAP_LOOKUP_ELEM:
4603 		err = map_lookup_elem(&attr);
4604 		break;
4605 	case BPF_MAP_UPDATE_ELEM:
4606 		err = map_update_elem(&attr, uattr);
4607 		break;
4608 	case BPF_MAP_DELETE_ELEM:
4609 		err = map_delete_elem(&attr);
4610 		break;
4611 	case BPF_MAP_GET_NEXT_KEY:
4612 		err = map_get_next_key(&attr);
4613 		break;
4614 	case BPF_MAP_FREEZE:
4615 		err = map_freeze(&attr);
4616 		break;
4617 	case BPF_PROG_LOAD:
4618 		err = bpf_prog_load(&attr, uattr);
4619 		break;
4620 	case BPF_OBJ_PIN:
4621 		err = bpf_obj_pin(&attr);
4622 		break;
4623 	case BPF_OBJ_GET:
4624 		err = bpf_obj_get(&attr);
4625 		break;
4626 	case BPF_PROG_ATTACH:
4627 		err = bpf_prog_attach(&attr);
4628 		break;
4629 	case BPF_PROG_DETACH:
4630 		err = bpf_prog_detach(&attr);
4631 		break;
4632 	case BPF_PROG_QUERY:
4633 		err = bpf_prog_query(&attr, uattr.user);
4634 		break;
4635 	case BPF_PROG_TEST_RUN:
4636 		err = bpf_prog_test_run(&attr, uattr.user);
4637 		break;
4638 	case BPF_PROG_GET_NEXT_ID:
4639 		err = bpf_obj_get_next_id(&attr, uattr.user,
4640 					  &prog_idr, &prog_idr_lock);
4641 		break;
4642 	case BPF_MAP_GET_NEXT_ID:
4643 		err = bpf_obj_get_next_id(&attr, uattr.user,
4644 					  &map_idr, &map_idr_lock);
4645 		break;
4646 	case BPF_BTF_GET_NEXT_ID:
4647 		err = bpf_obj_get_next_id(&attr, uattr.user,
4648 					  &btf_idr, &btf_idr_lock);
4649 		break;
4650 	case BPF_PROG_GET_FD_BY_ID:
4651 		err = bpf_prog_get_fd_by_id(&attr);
4652 		break;
4653 	case BPF_MAP_GET_FD_BY_ID:
4654 		err = bpf_map_get_fd_by_id(&attr);
4655 		break;
4656 	case BPF_OBJ_GET_INFO_BY_FD:
4657 		err = bpf_obj_get_info_by_fd(&attr, uattr.user);
4658 		break;
4659 	case BPF_RAW_TRACEPOINT_OPEN:
4660 		err = bpf_raw_tracepoint_open(&attr);
4661 		break;
4662 	case BPF_BTF_LOAD:
4663 		err = bpf_btf_load(&attr, uattr);
4664 		break;
4665 	case BPF_BTF_GET_FD_BY_ID:
4666 		err = bpf_btf_get_fd_by_id(&attr);
4667 		break;
4668 	case BPF_TASK_FD_QUERY:
4669 		err = bpf_task_fd_query(&attr, uattr.user);
4670 		break;
4671 	case BPF_MAP_LOOKUP_AND_DELETE_ELEM:
4672 		err = map_lookup_and_delete_elem(&attr);
4673 		break;
4674 	case BPF_MAP_LOOKUP_BATCH:
4675 		err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_LOOKUP_BATCH);
4676 		break;
4677 	case BPF_MAP_LOOKUP_AND_DELETE_BATCH:
4678 		err = bpf_map_do_batch(&attr, uattr.user,
4679 				       BPF_MAP_LOOKUP_AND_DELETE_BATCH);
4680 		break;
4681 	case BPF_MAP_UPDATE_BATCH:
4682 		err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_UPDATE_BATCH);
4683 		break;
4684 	case BPF_MAP_DELETE_BATCH:
4685 		err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_DELETE_BATCH);
4686 		break;
4687 	case BPF_LINK_CREATE:
4688 		err = link_create(&attr, uattr);
4689 		break;
4690 	case BPF_LINK_UPDATE:
4691 		err = link_update(&attr);
4692 		break;
4693 	case BPF_LINK_GET_FD_BY_ID:
4694 		err = bpf_link_get_fd_by_id(&attr);
4695 		break;
4696 	case BPF_LINK_GET_NEXT_ID:
4697 		err = bpf_obj_get_next_id(&attr, uattr.user,
4698 					  &link_idr, &link_idr_lock);
4699 		break;
4700 	case BPF_ENABLE_STATS:
4701 		err = bpf_enable_stats(&attr);
4702 		break;
4703 	case BPF_ITER_CREATE:
4704 		err = bpf_iter_create(&attr);
4705 		break;
4706 	case BPF_LINK_DETACH:
4707 		err = link_detach(&attr);
4708 		break;
4709 	case BPF_PROG_BIND_MAP:
4710 		err = bpf_prog_bind_map(&attr);
4711 		break;
4712 	default:
4713 		err = -EINVAL;
4714 		break;
4715 	}
4716 
4717 	return err;
4718 }
4719 
4720 SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size)
4721 {
4722 	return __sys_bpf(cmd, USER_BPFPTR(uattr), size);
4723 }
4724 
4725 static bool syscall_prog_is_valid_access(int off, int size,
4726 					 enum bpf_access_type type,
4727 					 const struct bpf_prog *prog,
4728 					 struct bpf_insn_access_aux *info)
4729 {
4730 	if (off < 0 || off >= U16_MAX)
4731 		return false;
4732 	if (off % size != 0)
4733 		return false;
4734 	return true;
4735 }
4736 
4737 BPF_CALL_3(bpf_sys_bpf, int, cmd, void *, attr, u32, attr_size)
4738 {
4739 	switch (cmd) {
4740 	case BPF_MAP_CREATE:
4741 	case BPF_MAP_UPDATE_ELEM:
4742 	case BPF_MAP_FREEZE:
4743 	case BPF_PROG_LOAD:
4744 	case BPF_BTF_LOAD:
4745 		break;
4746 	/* case BPF_PROG_TEST_RUN:
4747 	 * is not part of this list to prevent recursive test_run
4748 	 */
4749 	default:
4750 		return -EINVAL;
4751 	}
4752 	return __sys_bpf(cmd, KERNEL_BPFPTR(attr), attr_size);
4753 }
4754 
4755 static const struct bpf_func_proto bpf_sys_bpf_proto = {
4756 	.func		= bpf_sys_bpf,
4757 	.gpl_only	= false,
4758 	.ret_type	= RET_INTEGER,
4759 	.arg1_type	= ARG_ANYTHING,
4760 	.arg2_type	= ARG_PTR_TO_MEM,
4761 	.arg3_type	= ARG_CONST_SIZE,
4762 };
4763 
4764 const struct bpf_func_proto * __weak
4765 tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
4766 {
4767 	return bpf_base_func_proto(func_id);
4768 }
4769 
4770 BPF_CALL_1(bpf_sys_close, u32, fd)
4771 {
4772 	/* When bpf program calls this helper there should not be
4773 	 * an fdget() without matching completed fdput().
4774 	 * This helper is allowed in the following callchain only:
4775 	 * sys_bpf->prog_test_run->bpf_prog->bpf_sys_close
4776 	 */
4777 	return close_fd(fd);
4778 }
4779 
4780 static const struct bpf_func_proto bpf_sys_close_proto = {
4781 	.func		= bpf_sys_close,
4782 	.gpl_only	= false,
4783 	.ret_type	= RET_INTEGER,
4784 	.arg1_type	= ARG_ANYTHING,
4785 };
4786 
4787 BPF_CALL_4(bpf_kallsyms_lookup_name, const char *, name, int, name_sz, int, flags, u64 *, res)
4788 {
4789 	if (flags)
4790 		return -EINVAL;
4791 
4792 	if (name_sz <= 1 || name[name_sz - 1])
4793 		return -EINVAL;
4794 
4795 	if (!bpf_dump_raw_ok(current_cred()))
4796 		return -EPERM;
4797 
4798 	*res = kallsyms_lookup_name(name);
4799 	return *res ? 0 : -ENOENT;
4800 }
4801 
4802 const struct bpf_func_proto bpf_kallsyms_lookup_name_proto = {
4803 	.func		= bpf_kallsyms_lookup_name,
4804 	.gpl_only	= false,
4805 	.ret_type	= RET_INTEGER,
4806 	.arg1_type	= ARG_PTR_TO_MEM,
4807 	.arg2_type	= ARG_CONST_SIZE,
4808 	.arg3_type	= ARG_ANYTHING,
4809 	.arg4_type	= ARG_PTR_TO_LONG,
4810 };
4811 
4812 static const struct bpf_func_proto *
4813 syscall_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
4814 {
4815 	switch (func_id) {
4816 	case BPF_FUNC_sys_bpf:
4817 		return &bpf_sys_bpf_proto;
4818 	case BPF_FUNC_btf_find_by_name_kind:
4819 		return &bpf_btf_find_by_name_kind_proto;
4820 	case BPF_FUNC_sys_close:
4821 		return &bpf_sys_close_proto;
4822 	case BPF_FUNC_kallsyms_lookup_name:
4823 		return &bpf_kallsyms_lookup_name_proto;
4824 	default:
4825 		return tracing_prog_func_proto(func_id, prog);
4826 	}
4827 }
4828 
4829 const struct bpf_verifier_ops bpf_syscall_verifier_ops = {
4830 	.get_func_proto  = syscall_prog_func_proto,
4831 	.is_valid_access = syscall_prog_is_valid_access,
4832 };
4833 
4834 const struct bpf_prog_ops bpf_syscall_prog_ops = {
4835 	.test_run = bpf_prog_test_run_syscall,
4836 };
4837