xref: /linux/kernel/bpf/syscall.c (revision cc8c418b4fc09ed58ddd27b8e90ec797e9ca1e67)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
3  */
4 #include <linux/bpf.h>
5 #include <linux/bpf-cgroup.h>
6 #include <linux/bpf_trace.h>
7 #include <linux/bpf_lirc.h>
8 #include <linux/bpf_verifier.h>
9 #include <linux/bsearch.h>
10 #include <linux/btf.h>
11 #include <linux/syscalls.h>
12 #include <linux/slab.h>
13 #include <linux/sched/signal.h>
14 #include <linux/vmalloc.h>
15 #include <linux/mmzone.h>
16 #include <linux/anon_inodes.h>
17 #include <linux/fdtable.h>
18 #include <linux/file.h>
19 #include <linux/fs.h>
20 #include <linux/license.h>
21 #include <linux/filter.h>
22 #include <linux/kernel.h>
23 #include <linux/idr.h>
24 #include <linux/cred.h>
25 #include <linux/timekeeping.h>
26 #include <linux/ctype.h>
27 #include <linux/nospec.h>
28 #include <linux/audit.h>
29 #include <uapi/linux/btf.h>
30 #include <linux/pgtable.h>
31 #include <linux/bpf_lsm.h>
32 #include <linux/poll.h>
33 #include <linux/sort.h>
34 #include <linux/bpf-netns.h>
35 #include <linux/rcupdate_trace.h>
36 #include <linux/memcontrol.h>
37 #include <linux/trace_events.h>
38 
39 #define IS_FD_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || \
40 			  (map)->map_type == BPF_MAP_TYPE_CGROUP_ARRAY || \
41 			  (map)->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS)
42 #define IS_FD_PROG_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PROG_ARRAY)
43 #define IS_FD_HASH(map) ((map)->map_type == BPF_MAP_TYPE_HASH_OF_MAPS)
44 #define IS_FD_MAP(map) (IS_FD_ARRAY(map) || IS_FD_PROG_ARRAY(map) || \
45 			IS_FD_HASH(map))
46 
47 #define BPF_OBJ_FLAG_MASK   (BPF_F_RDONLY | BPF_F_WRONLY)
48 
49 DEFINE_PER_CPU(int, bpf_prog_active);
50 static DEFINE_IDR(prog_idr);
51 static DEFINE_SPINLOCK(prog_idr_lock);
52 static DEFINE_IDR(map_idr);
53 static DEFINE_SPINLOCK(map_idr_lock);
54 static DEFINE_IDR(link_idr);
55 static DEFINE_SPINLOCK(link_idr_lock);
56 
57 int sysctl_unprivileged_bpf_disabled __read_mostly =
58 	IS_BUILTIN(CONFIG_BPF_UNPRIV_DEFAULT_OFF) ? 2 : 0;
59 
60 static const struct bpf_map_ops * const bpf_map_types[] = {
61 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type)
62 #define BPF_MAP_TYPE(_id, _ops) \
63 	[_id] = &_ops,
64 #define BPF_LINK_TYPE(_id, _name)
65 #include <linux/bpf_types.h>
66 #undef BPF_PROG_TYPE
67 #undef BPF_MAP_TYPE
68 #undef BPF_LINK_TYPE
69 };
70 
71 /*
72  * If we're handed a bigger struct than we know of, ensure all the unknown bits
73  * are 0 - i.e. new user-space does not rely on any kernel feature extensions
74  * we don't know about yet.
75  *
76  * There is a ToCToU between this function call and the following
77  * copy_from_user() call. However, this is not a concern since this function is
78  * meant to be a future-proofing of bits.
79  */
80 int bpf_check_uarg_tail_zero(bpfptr_t uaddr,
81 			     size_t expected_size,
82 			     size_t actual_size)
83 {
84 	int res;
85 
86 	if (unlikely(actual_size > PAGE_SIZE))	/* silly large */
87 		return -E2BIG;
88 
89 	if (actual_size <= expected_size)
90 		return 0;
91 
92 	if (uaddr.is_kernel)
93 		res = memchr_inv(uaddr.kernel + expected_size, 0,
94 				 actual_size - expected_size) == NULL;
95 	else
96 		res = check_zeroed_user(uaddr.user + expected_size,
97 					actual_size - expected_size);
98 	if (res < 0)
99 		return res;
100 	return res ? 0 : -E2BIG;
101 }
102 
103 const struct bpf_map_ops bpf_map_offload_ops = {
104 	.map_meta_equal = bpf_map_meta_equal,
105 	.map_alloc = bpf_map_offload_map_alloc,
106 	.map_free = bpf_map_offload_map_free,
107 	.map_check_btf = map_check_no_btf,
108 };
109 
110 static struct bpf_map *find_and_alloc_map(union bpf_attr *attr)
111 {
112 	const struct bpf_map_ops *ops;
113 	u32 type = attr->map_type;
114 	struct bpf_map *map;
115 	int err;
116 
117 	if (type >= ARRAY_SIZE(bpf_map_types))
118 		return ERR_PTR(-EINVAL);
119 	type = array_index_nospec(type, ARRAY_SIZE(bpf_map_types));
120 	ops = bpf_map_types[type];
121 	if (!ops)
122 		return ERR_PTR(-EINVAL);
123 
124 	if (ops->map_alloc_check) {
125 		err = ops->map_alloc_check(attr);
126 		if (err)
127 			return ERR_PTR(err);
128 	}
129 	if (attr->map_ifindex)
130 		ops = &bpf_map_offload_ops;
131 	map = ops->map_alloc(attr);
132 	if (IS_ERR(map))
133 		return map;
134 	map->ops = ops;
135 	map->map_type = type;
136 	return map;
137 }
138 
139 static void bpf_map_write_active_inc(struct bpf_map *map)
140 {
141 	atomic64_inc(&map->writecnt);
142 }
143 
144 static void bpf_map_write_active_dec(struct bpf_map *map)
145 {
146 	atomic64_dec(&map->writecnt);
147 }
148 
149 bool bpf_map_write_active(const struct bpf_map *map)
150 {
151 	return atomic64_read(&map->writecnt) != 0;
152 }
153 
154 static u32 bpf_map_value_size(const struct bpf_map *map)
155 {
156 	if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
157 	    map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH ||
158 	    map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY ||
159 	    map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE)
160 		return round_up(map->value_size, 8) * num_possible_cpus();
161 	else if (IS_FD_MAP(map))
162 		return sizeof(u32);
163 	else
164 		return  map->value_size;
165 }
166 
167 static void maybe_wait_bpf_programs(struct bpf_map *map)
168 {
169 	/* Wait for any running BPF programs to complete so that
170 	 * userspace, when we return to it, knows that all programs
171 	 * that could be running use the new map value.
172 	 */
173 	if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS ||
174 	    map->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS)
175 		synchronize_rcu();
176 }
177 
178 static int bpf_map_update_value(struct bpf_map *map, struct fd f, void *key,
179 				void *value, __u64 flags)
180 {
181 	int err;
182 
183 	/* Need to create a kthread, thus must support schedule */
184 	if (bpf_map_is_dev_bound(map)) {
185 		return bpf_map_offload_update_elem(map, key, value, flags);
186 	} else if (map->map_type == BPF_MAP_TYPE_CPUMAP ||
187 		   map->map_type == BPF_MAP_TYPE_STRUCT_OPS) {
188 		return map->ops->map_update_elem(map, key, value, flags);
189 	} else if (map->map_type == BPF_MAP_TYPE_SOCKHASH ||
190 		   map->map_type == BPF_MAP_TYPE_SOCKMAP) {
191 		return sock_map_update_elem_sys(map, key, value, flags);
192 	} else if (IS_FD_PROG_ARRAY(map)) {
193 		return bpf_fd_array_map_update_elem(map, f.file, key, value,
194 						    flags);
195 	}
196 
197 	bpf_disable_instrumentation();
198 	if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
199 	    map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
200 		err = bpf_percpu_hash_update(map, key, value, flags);
201 	} else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) {
202 		err = bpf_percpu_array_update(map, key, value, flags);
203 	} else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) {
204 		err = bpf_percpu_cgroup_storage_update(map, key, value,
205 						       flags);
206 	} else if (IS_FD_ARRAY(map)) {
207 		rcu_read_lock();
208 		err = bpf_fd_array_map_update_elem(map, f.file, key, value,
209 						   flags);
210 		rcu_read_unlock();
211 	} else if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) {
212 		rcu_read_lock();
213 		err = bpf_fd_htab_map_update_elem(map, f.file, key, value,
214 						  flags);
215 		rcu_read_unlock();
216 	} else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) {
217 		/* rcu_read_lock() is not needed */
218 		err = bpf_fd_reuseport_array_update_elem(map, key, value,
219 							 flags);
220 	} else if (map->map_type == BPF_MAP_TYPE_QUEUE ||
221 		   map->map_type == BPF_MAP_TYPE_STACK ||
222 		   map->map_type == BPF_MAP_TYPE_BLOOM_FILTER) {
223 		err = map->ops->map_push_elem(map, value, flags);
224 	} else {
225 		rcu_read_lock();
226 		err = map->ops->map_update_elem(map, key, value, flags);
227 		rcu_read_unlock();
228 	}
229 	bpf_enable_instrumentation();
230 	maybe_wait_bpf_programs(map);
231 
232 	return err;
233 }
234 
235 static int bpf_map_copy_value(struct bpf_map *map, void *key, void *value,
236 			      __u64 flags)
237 {
238 	void *ptr;
239 	int err;
240 
241 	if (bpf_map_is_dev_bound(map))
242 		return bpf_map_offload_lookup_elem(map, key, value);
243 
244 	bpf_disable_instrumentation();
245 	if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
246 	    map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
247 		err = bpf_percpu_hash_copy(map, key, value);
248 	} else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) {
249 		err = bpf_percpu_array_copy(map, key, value);
250 	} else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) {
251 		err = bpf_percpu_cgroup_storage_copy(map, key, value);
252 	} else if (map->map_type == BPF_MAP_TYPE_STACK_TRACE) {
253 		err = bpf_stackmap_copy(map, key, value);
254 	} else if (IS_FD_ARRAY(map) || IS_FD_PROG_ARRAY(map)) {
255 		err = bpf_fd_array_map_lookup_elem(map, key, value);
256 	} else if (IS_FD_HASH(map)) {
257 		err = bpf_fd_htab_map_lookup_elem(map, key, value);
258 	} else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) {
259 		err = bpf_fd_reuseport_array_lookup_elem(map, key, value);
260 	} else if (map->map_type == BPF_MAP_TYPE_QUEUE ||
261 		   map->map_type == BPF_MAP_TYPE_STACK ||
262 		   map->map_type == BPF_MAP_TYPE_BLOOM_FILTER) {
263 		err = map->ops->map_peek_elem(map, value);
264 	} else if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS) {
265 		/* struct_ops map requires directly updating "value" */
266 		err = bpf_struct_ops_map_sys_lookup_elem(map, key, value);
267 	} else {
268 		rcu_read_lock();
269 		if (map->ops->map_lookup_elem_sys_only)
270 			ptr = map->ops->map_lookup_elem_sys_only(map, key);
271 		else
272 			ptr = map->ops->map_lookup_elem(map, key);
273 		if (IS_ERR(ptr)) {
274 			err = PTR_ERR(ptr);
275 		} else if (!ptr) {
276 			err = -ENOENT;
277 		} else {
278 			err = 0;
279 			if (flags & BPF_F_LOCK)
280 				/* lock 'ptr' and copy everything but lock */
281 				copy_map_value_locked(map, value, ptr, true);
282 			else
283 				copy_map_value(map, value, ptr);
284 			/* mask lock and timer, since value wasn't zero inited */
285 			check_and_init_map_value(map, value);
286 		}
287 		rcu_read_unlock();
288 	}
289 
290 	bpf_enable_instrumentation();
291 	maybe_wait_bpf_programs(map);
292 
293 	return err;
294 }
295 
296 /* Please, do not use this function outside from the map creation path
297  * (e.g. in map update path) without taking care of setting the active
298  * memory cgroup (see at bpf_map_kmalloc_node() for example).
299  */
300 static void *__bpf_map_area_alloc(u64 size, int numa_node, bool mmapable)
301 {
302 	/* We really just want to fail instead of triggering OOM killer
303 	 * under memory pressure, therefore we set __GFP_NORETRY to kmalloc,
304 	 * which is used for lower order allocation requests.
305 	 *
306 	 * It has been observed that higher order allocation requests done by
307 	 * vmalloc with __GFP_NORETRY being set might fail due to not trying
308 	 * to reclaim memory from the page cache, thus we set
309 	 * __GFP_RETRY_MAYFAIL to avoid such situations.
310 	 */
311 
312 	const gfp_t gfp = __GFP_NOWARN | __GFP_ZERO | __GFP_ACCOUNT;
313 	unsigned int flags = 0;
314 	unsigned long align = 1;
315 	void *area;
316 
317 	if (size >= SIZE_MAX)
318 		return NULL;
319 
320 	/* kmalloc()'ed memory can't be mmap()'ed */
321 	if (mmapable) {
322 		BUG_ON(!PAGE_ALIGNED(size));
323 		align = SHMLBA;
324 		flags = VM_USERMAP;
325 	} else if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) {
326 		area = kmalloc_node(size, gfp | GFP_USER | __GFP_NORETRY,
327 				    numa_node);
328 		if (area != NULL)
329 			return area;
330 	}
331 
332 	return __vmalloc_node_range(size, align, VMALLOC_START, VMALLOC_END,
333 			gfp | GFP_KERNEL | __GFP_RETRY_MAYFAIL, PAGE_KERNEL,
334 			flags, numa_node, __builtin_return_address(0));
335 }
336 
337 void *bpf_map_area_alloc(u64 size, int numa_node)
338 {
339 	return __bpf_map_area_alloc(size, numa_node, false);
340 }
341 
342 void *bpf_map_area_mmapable_alloc(u64 size, int numa_node)
343 {
344 	return __bpf_map_area_alloc(size, numa_node, true);
345 }
346 
347 void bpf_map_area_free(void *area)
348 {
349 	kvfree(area);
350 }
351 
352 static u32 bpf_map_flags_retain_permanent(u32 flags)
353 {
354 	/* Some map creation flags are not tied to the map object but
355 	 * rather to the map fd instead, so they have no meaning upon
356 	 * map object inspection since multiple file descriptors with
357 	 * different (access) properties can exist here. Thus, given
358 	 * this has zero meaning for the map itself, lets clear these
359 	 * from here.
360 	 */
361 	return flags & ~(BPF_F_RDONLY | BPF_F_WRONLY);
362 }
363 
364 void bpf_map_init_from_attr(struct bpf_map *map, union bpf_attr *attr)
365 {
366 	map->map_type = attr->map_type;
367 	map->key_size = attr->key_size;
368 	map->value_size = attr->value_size;
369 	map->max_entries = attr->max_entries;
370 	map->map_flags = bpf_map_flags_retain_permanent(attr->map_flags);
371 	map->numa_node = bpf_map_attr_numa_node(attr);
372 	map->map_extra = attr->map_extra;
373 }
374 
375 static int bpf_map_alloc_id(struct bpf_map *map)
376 {
377 	int id;
378 
379 	idr_preload(GFP_KERNEL);
380 	spin_lock_bh(&map_idr_lock);
381 	id = idr_alloc_cyclic(&map_idr, map, 1, INT_MAX, GFP_ATOMIC);
382 	if (id > 0)
383 		map->id = id;
384 	spin_unlock_bh(&map_idr_lock);
385 	idr_preload_end();
386 
387 	if (WARN_ON_ONCE(!id))
388 		return -ENOSPC;
389 
390 	return id > 0 ? 0 : id;
391 }
392 
393 void bpf_map_free_id(struct bpf_map *map, bool do_idr_lock)
394 {
395 	unsigned long flags;
396 
397 	/* Offloaded maps are removed from the IDR store when their device
398 	 * disappears - even if someone holds an fd to them they are unusable,
399 	 * the memory is gone, all ops will fail; they are simply waiting for
400 	 * refcnt to drop to be freed.
401 	 */
402 	if (!map->id)
403 		return;
404 
405 	if (do_idr_lock)
406 		spin_lock_irqsave(&map_idr_lock, flags);
407 	else
408 		__acquire(&map_idr_lock);
409 
410 	idr_remove(&map_idr, map->id);
411 	map->id = 0;
412 
413 	if (do_idr_lock)
414 		spin_unlock_irqrestore(&map_idr_lock, flags);
415 	else
416 		__release(&map_idr_lock);
417 }
418 
419 #ifdef CONFIG_MEMCG_KMEM
420 static void bpf_map_save_memcg(struct bpf_map *map)
421 {
422 	/* Currently if a map is created by a process belonging to the root
423 	 * memory cgroup, get_obj_cgroup_from_current() will return NULL.
424 	 * So we have to check map->objcg for being NULL each time it's
425 	 * being used.
426 	 */
427 	map->objcg = get_obj_cgroup_from_current();
428 }
429 
430 static void bpf_map_release_memcg(struct bpf_map *map)
431 {
432 	if (map->objcg)
433 		obj_cgroup_put(map->objcg);
434 }
435 
436 static struct mem_cgroup *bpf_map_get_memcg(const struct bpf_map *map)
437 {
438 	if (map->objcg)
439 		return get_mem_cgroup_from_objcg(map->objcg);
440 
441 	return root_mem_cgroup;
442 }
443 
444 void *bpf_map_kmalloc_node(const struct bpf_map *map, size_t size, gfp_t flags,
445 			   int node)
446 {
447 	struct mem_cgroup *memcg, *old_memcg;
448 	void *ptr;
449 
450 	memcg = bpf_map_get_memcg(map);
451 	old_memcg = set_active_memcg(memcg);
452 	ptr = kmalloc_node(size, flags | __GFP_ACCOUNT, node);
453 	set_active_memcg(old_memcg);
454 	mem_cgroup_put(memcg);
455 
456 	return ptr;
457 }
458 
459 void *bpf_map_kzalloc(const struct bpf_map *map, size_t size, gfp_t flags)
460 {
461 	struct mem_cgroup *memcg, *old_memcg;
462 	void *ptr;
463 
464 	memcg = bpf_map_get_memcg(map);
465 	old_memcg = set_active_memcg(memcg);
466 	ptr = kzalloc(size, flags | __GFP_ACCOUNT);
467 	set_active_memcg(old_memcg);
468 	mem_cgroup_put(memcg);
469 
470 	return ptr;
471 }
472 
473 void __percpu *bpf_map_alloc_percpu(const struct bpf_map *map, size_t size,
474 				    size_t align, gfp_t flags)
475 {
476 	struct mem_cgroup *memcg, *old_memcg;
477 	void __percpu *ptr;
478 
479 	memcg = bpf_map_get_memcg(map);
480 	old_memcg = set_active_memcg(memcg);
481 	ptr = __alloc_percpu_gfp(size, align, flags | __GFP_ACCOUNT);
482 	set_active_memcg(old_memcg);
483 	mem_cgroup_put(memcg);
484 
485 	return ptr;
486 }
487 
488 #else
489 static void bpf_map_save_memcg(struct bpf_map *map)
490 {
491 }
492 
493 static void bpf_map_release_memcg(struct bpf_map *map)
494 {
495 }
496 #endif
497 
498 static int bpf_map_kptr_off_cmp(const void *a, const void *b)
499 {
500 	const struct bpf_map_value_off_desc *off_desc1 = a, *off_desc2 = b;
501 
502 	if (off_desc1->offset < off_desc2->offset)
503 		return -1;
504 	else if (off_desc1->offset > off_desc2->offset)
505 		return 1;
506 	return 0;
507 }
508 
509 struct bpf_map_value_off_desc *bpf_map_kptr_off_contains(struct bpf_map *map, u32 offset)
510 {
511 	/* Since members are iterated in btf_find_field in increasing order,
512 	 * offsets appended to kptr_off_tab are in increasing order, so we can
513 	 * do bsearch to find exact match.
514 	 */
515 	struct bpf_map_value_off *tab;
516 
517 	if (!map_value_has_kptrs(map))
518 		return NULL;
519 	tab = map->kptr_off_tab;
520 	return bsearch(&offset, tab->off, tab->nr_off, sizeof(tab->off[0]), bpf_map_kptr_off_cmp);
521 }
522 
523 void bpf_map_free_kptr_off_tab(struct bpf_map *map)
524 {
525 	struct bpf_map_value_off *tab = map->kptr_off_tab;
526 	int i;
527 
528 	if (!map_value_has_kptrs(map))
529 		return;
530 	for (i = 0; i < tab->nr_off; i++) {
531 		if (tab->off[i].kptr.module)
532 			module_put(tab->off[i].kptr.module);
533 		btf_put(tab->off[i].kptr.btf);
534 	}
535 	kfree(tab);
536 	map->kptr_off_tab = NULL;
537 }
538 
539 struct bpf_map_value_off *bpf_map_copy_kptr_off_tab(const struct bpf_map *map)
540 {
541 	struct bpf_map_value_off *tab = map->kptr_off_tab, *new_tab;
542 	int size, i;
543 
544 	if (!map_value_has_kptrs(map))
545 		return ERR_PTR(-ENOENT);
546 	size = offsetof(struct bpf_map_value_off, off[tab->nr_off]);
547 	new_tab = kmemdup(tab, size, GFP_KERNEL | __GFP_NOWARN);
548 	if (!new_tab)
549 		return ERR_PTR(-ENOMEM);
550 	/* Do a deep copy of the kptr_off_tab */
551 	for (i = 0; i < tab->nr_off; i++) {
552 		btf_get(tab->off[i].kptr.btf);
553 		if (tab->off[i].kptr.module && !try_module_get(tab->off[i].kptr.module)) {
554 			while (i--) {
555 				if (tab->off[i].kptr.module)
556 					module_put(tab->off[i].kptr.module);
557 				btf_put(tab->off[i].kptr.btf);
558 			}
559 			kfree(new_tab);
560 			return ERR_PTR(-ENXIO);
561 		}
562 	}
563 	return new_tab;
564 }
565 
566 bool bpf_map_equal_kptr_off_tab(const struct bpf_map *map_a, const struct bpf_map *map_b)
567 {
568 	struct bpf_map_value_off *tab_a = map_a->kptr_off_tab, *tab_b = map_b->kptr_off_tab;
569 	bool a_has_kptr = map_value_has_kptrs(map_a), b_has_kptr = map_value_has_kptrs(map_b);
570 	int size;
571 
572 	if (!a_has_kptr && !b_has_kptr)
573 		return true;
574 	if (a_has_kptr != b_has_kptr)
575 		return false;
576 	if (tab_a->nr_off != tab_b->nr_off)
577 		return false;
578 	size = offsetof(struct bpf_map_value_off, off[tab_a->nr_off]);
579 	return !memcmp(tab_a, tab_b, size);
580 }
581 
582 /* Caller must ensure map_value_has_kptrs is true. Note that this function can
583  * be called on a map value while the map_value is visible to BPF programs, as
584  * it ensures the correct synchronization, and we already enforce the same using
585  * the bpf_kptr_xchg helper on the BPF program side for referenced kptrs.
586  */
587 void bpf_map_free_kptrs(struct bpf_map *map, void *map_value)
588 {
589 	struct bpf_map_value_off *tab = map->kptr_off_tab;
590 	unsigned long *btf_id_ptr;
591 	int i;
592 
593 	for (i = 0; i < tab->nr_off; i++) {
594 		struct bpf_map_value_off_desc *off_desc = &tab->off[i];
595 		unsigned long old_ptr;
596 
597 		btf_id_ptr = map_value + off_desc->offset;
598 		if (off_desc->type == BPF_KPTR_UNREF) {
599 			u64 *p = (u64 *)btf_id_ptr;
600 
601 			WRITE_ONCE(*p, 0);
602 			continue;
603 		}
604 		old_ptr = xchg(btf_id_ptr, 0);
605 		off_desc->kptr.dtor((void *)old_ptr);
606 	}
607 }
608 
609 /* called from workqueue */
610 static void bpf_map_free_deferred(struct work_struct *work)
611 {
612 	struct bpf_map *map = container_of(work, struct bpf_map, work);
613 
614 	security_bpf_map_free(map);
615 	kfree(map->off_arr);
616 	bpf_map_release_memcg(map);
617 	/* implementation dependent freeing, map_free callback also does
618 	 * bpf_map_free_kptr_off_tab, if needed.
619 	 */
620 	map->ops->map_free(map);
621 }
622 
623 static void bpf_map_put_uref(struct bpf_map *map)
624 {
625 	if (atomic64_dec_and_test(&map->usercnt)) {
626 		if (map->ops->map_release_uref)
627 			map->ops->map_release_uref(map);
628 	}
629 }
630 
631 /* decrement map refcnt and schedule it for freeing via workqueue
632  * (unrelying map implementation ops->map_free() might sleep)
633  */
634 static void __bpf_map_put(struct bpf_map *map, bool do_idr_lock)
635 {
636 	if (atomic64_dec_and_test(&map->refcnt)) {
637 		/* bpf_map_free_id() must be called first */
638 		bpf_map_free_id(map, do_idr_lock);
639 		btf_put(map->btf);
640 		INIT_WORK(&map->work, bpf_map_free_deferred);
641 		/* Avoid spawning kworkers, since they all might contend
642 		 * for the same mutex like slab_mutex.
643 		 */
644 		queue_work(system_unbound_wq, &map->work);
645 	}
646 }
647 
648 void bpf_map_put(struct bpf_map *map)
649 {
650 	__bpf_map_put(map, true);
651 }
652 EXPORT_SYMBOL_GPL(bpf_map_put);
653 
654 void bpf_map_put_with_uref(struct bpf_map *map)
655 {
656 	bpf_map_put_uref(map);
657 	bpf_map_put(map);
658 }
659 
660 static int bpf_map_release(struct inode *inode, struct file *filp)
661 {
662 	struct bpf_map *map = filp->private_data;
663 
664 	if (map->ops->map_release)
665 		map->ops->map_release(map, filp);
666 
667 	bpf_map_put_with_uref(map);
668 	return 0;
669 }
670 
671 static fmode_t map_get_sys_perms(struct bpf_map *map, struct fd f)
672 {
673 	fmode_t mode = f.file->f_mode;
674 
675 	/* Our file permissions may have been overridden by global
676 	 * map permissions facing syscall side.
677 	 */
678 	if (READ_ONCE(map->frozen))
679 		mode &= ~FMODE_CAN_WRITE;
680 	return mode;
681 }
682 
683 #ifdef CONFIG_PROC_FS
684 /* Provides an approximation of the map's memory footprint.
685  * Used only to provide a backward compatibility and display
686  * a reasonable "memlock" info.
687  */
688 static unsigned long bpf_map_memory_footprint(const struct bpf_map *map)
689 {
690 	unsigned long size;
691 
692 	size = round_up(map->key_size + bpf_map_value_size(map), 8);
693 
694 	return round_up(map->max_entries * size, PAGE_SIZE);
695 }
696 
697 static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp)
698 {
699 	struct bpf_map *map = filp->private_data;
700 	u32 type = 0, jited = 0;
701 
702 	if (map_type_contains_progs(map)) {
703 		spin_lock(&map->owner.lock);
704 		type  = map->owner.type;
705 		jited = map->owner.jited;
706 		spin_unlock(&map->owner.lock);
707 	}
708 
709 	seq_printf(m,
710 		   "map_type:\t%u\n"
711 		   "key_size:\t%u\n"
712 		   "value_size:\t%u\n"
713 		   "max_entries:\t%u\n"
714 		   "map_flags:\t%#x\n"
715 		   "map_extra:\t%#llx\n"
716 		   "memlock:\t%lu\n"
717 		   "map_id:\t%u\n"
718 		   "frozen:\t%u\n",
719 		   map->map_type,
720 		   map->key_size,
721 		   map->value_size,
722 		   map->max_entries,
723 		   map->map_flags,
724 		   (unsigned long long)map->map_extra,
725 		   bpf_map_memory_footprint(map),
726 		   map->id,
727 		   READ_ONCE(map->frozen));
728 	if (type) {
729 		seq_printf(m, "owner_prog_type:\t%u\n", type);
730 		seq_printf(m, "owner_jited:\t%u\n", jited);
731 	}
732 }
733 #endif
734 
735 static ssize_t bpf_dummy_read(struct file *filp, char __user *buf, size_t siz,
736 			      loff_t *ppos)
737 {
738 	/* We need this handler such that alloc_file() enables
739 	 * f_mode with FMODE_CAN_READ.
740 	 */
741 	return -EINVAL;
742 }
743 
744 static ssize_t bpf_dummy_write(struct file *filp, const char __user *buf,
745 			       size_t siz, loff_t *ppos)
746 {
747 	/* We need this handler such that alloc_file() enables
748 	 * f_mode with FMODE_CAN_WRITE.
749 	 */
750 	return -EINVAL;
751 }
752 
753 /* called for any extra memory-mapped regions (except initial) */
754 static void bpf_map_mmap_open(struct vm_area_struct *vma)
755 {
756 	struct bpf_map *map = vma->vm_file->private_data;
757 
758 	if (vma->vm_flags & VM_MAYWRITE)
759 		bpf_map_write_active_inc(map);
760 }
761 
762 /* called for all unmapped memory region (including initial) */
763 static void bpf_map_mmap_close(struct vm_area_struct *vma)
764 {
765 	struct bpf_map *map = vma->vm_file->private_data;
766 
767 	if (vma->vm_flags & VM_MAYWRITE)
768 		bpf_map_write_active_dec(map);
769 }
770 
771 static const struct vm_operations_struct bpf_map_default_vmops = {
772 	.open		= bpf_map_mmap_open,
773 	.close		= bpf_map_mmap_close,
774 };
775 
776 static int bpf_map_mmap(struct file *filp, struct vm_area_struct *vma)
777 {
778 	struct bpf_map *map = filp->private_data;
779 	int err;
780 
781 	if (!map->ops->map_mmap || map_value_has_spin_lock(map) ||
782 	    map_value_has_timer(map) || map_value_has_kptrs(map))
783 		return -ENOTSUPP;
784 
785 	if (!(vma->vm_flags & VM_SHARED))
786 		return -EINVAL;
787 
788 	mutex_lock(&map->freeze_mutex);
789 
790 	if (vma->vm_flags & VM_WRITE) {
791 		if (map->frozen) {
792 			err = -EPERM;
793 			goto out;
794 		}
795 		/* map is meant to be read-only, so do not allow mapping as
796 		 * writable, because it's possible to leak a writable page
797 		 * reference and allows user-space to still modify it after
798 		 * freezing, while verifier will assume contents do not change
799 		 */
800 		if (map->map_flags & BPF_F_RDONLY_PROG) {
801 			err = -EACCES;
802 			goto out;
803 		}
804 	}
805 
806 	/* set default open/close callbacks */
807 	vma->vm_ops = &bpf_map_default_vmops;
808 	vma->vm_private_data = map;
809 	vma->vm_flags &= ~VM_MAYEXEC;
810 	if (!(vma->vm_flags & VM_WRITE))
811 		/* disallow re-mapping with PROT_WRITE */
812 		vma->vm_flags &= ~VM_MAYWRITE;
813 
814 	err = map->ops->map_mmap(map, vma);
815 	if (err)
816 		goto out;
817 
818 	if (vma->vm_flags & VM_MAYWRITE)
819 		bpf_map_write_active_inc(map);
820 out:
821 	mutex_unlock(&map->freeze_mutex);
822 	return err;
823 }
824 
825 static __poll_t bpf_map_poll(struct file *filp, struct poll_table_struct *pts)
826 {
827 	struct bpf_map *map = filp->private_data;
828 
829 	if (map->ops->map_poll)
830 		return map->ops->map_poll(map, filp, pts);
831 
832 	return EPOLLERR;
833 }
834 
835 const struct file_operations bpf_map_fops = {
836 #ifdef CONFIG_PROC_FS
837 	.show_fdinfo	= bpf_map_show_fdinfo,
838 #endif
839 	.release	= bpf_map_release,
840 	.read		= bpf_dummy_read,
841 	.write		= bpf_dummy_write,
842 	.mmap		= bpf_map_mmap,
843 	.poll		= bpf_map_poll,
844 };
845 
846 int bpf_map_new_fd(struct bpf_map *map, int flags)
847 {
848 	int ret;
849 
850 	ret = security_bpf_map(map, OPEN_FMODE(flags));
851 	if (ret < 0)
852 		return ret;
853 
854 	return anon_inode_getfd("bpf-map", &bpf_map_fops, map,
855 				flags | O_CLOEXEC);
856 }
857 
858 int bpf_get_file_flag(int flags)
859 {
860 	if ((flags & BPF_F_RDONLY) && (flags & BPF_F_WRONLY))
861 		return -EINVAL;
862 	if (flags & BPF_F_RDONLY)
863 		return O_RDONLY;
864 	if (flags & BPF_F_WRONLY)
865 		return O_WRONLY;
866 	return O_RDWR;
867 }
868 
869 /* helper macro to check that unused fields 'union bpf_attr' are zero */
870 #define CHECK_ATTR(CMD) \
871 	memchr_inv((void *) &attr->CMD##_LAST_FIELD + \
872 		   sizeof(attr->CMD##_LAST_FIELD), 0, \
873 		   sizeof(*attr) - \
874 		   offsetof(union bpf_attr, CMD##_LAST_FIELD) - \
875 		   sizeof(attr->CMD##_LAST_FIELD)) != NULL
876 
877 /* dst and src must have at least "size" number of bytes.
878  * Return strlen on success and < 0 on error.
879  */
880 int bpf_obj_name_cpy(char *dst, const char *src, unsigned int size)
881 {
882 	const char *end = src + size;
883 	const char *orig_src = src;
884 
885 	memset(dst, 0, size);
886 	/* Copy all isalnum(), '_' and '.' chars. */
887 	while (src < end && *src) {
888 		if (!isalnum(*src) &&
889 		    *src != '_' && *src != '.')
890 			return -EINVAL;
891 		*dst++ = *src++;
892 	}
893 
894 	/* No '\0' found in "size" number of bytes */
895 	if (src == end)
896 		return -EINVAL;
897 
898 	return src - orig_src;
899 }
900 
901 int map_check_no_btf(const struct bpf_map *map,
902 		     const struct btf *btf,
903 		     const struct btf_type *key_type,
904 		     const struct btf_type *value_type)
905 {
906 	return -ENOTSUPP;
907 }
908 
909 static int map_off_arr_cmp(const void *_a, const void *_b, const void *priv)
910 {
911 	const u32 a = *(const u32 *)_a;
912 	const u32 b = *(const u32 *)_b;
913 
914 	if (a < b)
915 		return -1;
916 	else if (a > b)
917 		return 1;
918 	return 0;
919 }
920 
921 static void map_off_arr_swap(void *_a, void *_b, int size, const void *priv)
922 {
923 	struct bpf_map *map = (struct bpf_map *)priv;
924 	u32 *off_base = map->off_arr->field_off;
925 	u32 *a = _a, *b = _b;
926 	u8 *sz_a, *sz_b;
927 
928 	sz_a = map->off_arr->field_sz + (a - off_base);
929 	sz_b = map->off_arr->field_sz + (b - off_base);
930 
931 	swap(*a, *b);
932 	swap(*sz_a, *sz_b);
933 }
934 
935 static int bpf_map_alloc_off_arr(struct bpf_map *map)
936 {
937 	bool has_spin_lock = map_value_has_spin_lock(map);
938 	bool has_timer = map_value_has_timer(map);
939 	bool has_kptrs = map_value_has_kptrs(map);
940 	struct bpf_map_off_arr *off_arr;
941 	u32 i;
942 
943 	if (!has_spin_lock && !has_timer && !has_kptrs) {
944 		map->off_arr = NULL;
945 		return 0;
946 	}
947 
948 	off_arr = kmalloc(sizeof(*map->off_arr), GFP_KERNEL | __GFP_NOWARN);
949 	if (!off_arr)
950 		return -ENOMEM;
951 	map->off_arr = off_arr;
952 
953 	off_arr->cnt = 0;
954 	if (has_spin_lock) {
955 		i = off_arr->cnt;
956 
957 		off_arr->field_off[i] = map->spin_lock_off;
958 		off_arr->field_sz[i] = sizeof(struct bpf_spin_lock);
959 		off_arr->cnt++;
960 	}
961 	if (has_timer) {
962 		i = off_arr->cnt;
963 
964 		off_arr->field_off[i] = map->timer_off;
965 		off_arr->field_sz[i] = sizeof(struct bpf_timer);
966 		off_arr->cnt++;
967 	}
968 	if (has_kptrs) {
969 		struct bpf_map_value_off *tab = map->kptr_off_tab;
970 		u32 *off = &off_arr->field_off[off_arr->cnt];
971 		u8 *sz = &off_arr->field_sz[off_arr->cnt];
972 
973 		for (i = 0; i < tab->nr_off; i++) {
974 			*off++ = tab->off[i].offset;
975 			*sz++ = sizeof(u64);
976 		}
977 		off_arr->cnt += tab->nr_off;
978 	}
979 
980 	if (off_arr->cnt == 1)
981 		return 0;
982 	sort_r(off_arr->field_off, off_arr->cnt, sizeof(off_arr->field_off[0]),
983 	       map_off_arr_cmp, map_off_arr_swap, map);
984 	return 0;
985 }
986 
987 static int map_check_btf(struct bpf_map *map, const struct btf *btf,
988 			 u32 btf_key_id, u32 btf_value_id)
989 {
990 	const struct btf_type *key_type, *value_type;
991 	u32 key_size, value_size;
992 	int ret = 0;
993 
994 	/* Some maps allow key to be unspecified. */
995 	if (btf_key_id) {
996 		key_type = btf_type_id_size(btf, &btf_key_id, &key_size);
997 		if (!key_type || key_size != map->key_size)
998 			return -EINVAL;
999 	} else {
1000 		key_type = btf_type_by_id(btf, 0);
1001 		if (!map->ops->map_check_btf)
1002 			return -EINVAL;
1003 	}
1004 
1005 	value_type = btf_type_id_size(btf, &btf_value_id, &value_size);
1006 	if (!value_type || value_size != map->value_size)
1007 		return -EINVAL;
1008 
1009 	map->spin_lock_off = btf_find_spin_lock(btf, value_type);
1010 
1011 	if (map_value_has_spin_lock(map)) {
1012 		if (map->map_flags & BPF_F_RDONLY_PROG)
1013 			return -EACCES;
1014 		if (map->map_type != BPF_MAP_TYPE_HASH &&
1015 		    map->map_type != BPF_MAP_TYPE_ARRAY &&
1016 		    map->map_type != BPF_MAP_TYPE_CGROUP_STORAGE &&
1017 		    map->map_type != BPF_MAP_TYPE_SK_STORAGE &&
1018 		    map->map_type != BPF_MAP_TYPE_INODE_STORAGE &&
1019 		    map->map_type != BPF_MAP_TYPE_TASK_STORAGE)
1020 			return -ENOTSUPP;
1021 		if (map->spin_lock_off + sizeof(struct bpf_spin_lock) >
1022 		    map->value_size) {
1023 			WARN_ONCE(1,
1024 				  "verifier bug spin_lock_off %d value_size %d\n",
1025 				  map->spin_lock_off, map->value_size);
1026 			return -EFAULT;
1027 		}
1028 	}
1029 
1030 	map->timer_off = btf_find_timer(btf, value_type);
1031 	if (map_value_has_timer(map)) {
1032 		if (map->map_flags & BPF_F_RDONLY_PROG)
1033 			return -EACCES;
1034 		if (map->map_type != BPF_MAP_TYPE_HASH &&
1035 		    map->map_type != BPF_MAP_TYPE_LRU_HASH &&
1036 		    map->map_type != BPF_MAP_TYPE_ARRAY)
1037 			return -EOPNOTSUPP;
1038 	}
1039 
1040 	map->kptr_off_tab = btf_parse_kptrs(btf, value_type);
1041 	if (map_value_has_kptrs(map)) {
1042 		if (!bpf_capable()) {
1043 			ret = -EPERM;
1044 			goto free_map_tab;
1045 		}
1046 		if (map->map_flags & (BPF_F_RDONLY_PROG | BPF_F_WRONLY_PROG)) {
1047 			ret = -EACCES;
1048 			goto free_map_tab;
1049 		}
1050 		if (map->map_type != BPF_MAP_TYPE_HASH &&
1051 		    map->map_type != BPF_MAP_TYPE_LRU_HASH &&
1052 		    map->map_type != BPF_MAP_TYPE_ARRAY &&
1053 		    map->map_type != BPF_MAP_TYPE_PERCPU_ARRAY) {
1054 			ret = -EOPNOTSUPP;
1055 			goto free_map_tab;
1056 		}
1057 	}
1058 
1059 	if (map->ops->map_check_btf) {
1060 		ret = map->ops->map_check_btf(map, btf, key_type, value_type);
1061 		if (ret < 0)
1062 			goto free_map_tab;
1063 	}
1064 
1065 	return ret;
1066 free_map_tab:
1067 	bpf_map_free_kptr_off_tab(map);
1068 	return ret;
1069 }
1070 
1071 #define BPF_MAP_CREATE_LAST_FIELD map_extra
1072 /* called via syscall */
1073 static int map_create(union bpf_attr *attr)
1074 {
1075 	int numa_node = bpf_map_attr_numa_node(attr);
1076 	struct bpf_map *map;
1077 	int f_flags;
1078 	int err;
1079 
1080 	err = CHECK_ATTR(BPF_MAP_CREATE);
1081 	if (err)
1082 		return -EINVAL;
1083 
1084 	if (attr->btf_vmlinux_value_type_id) {
1085 		if (attr->map_type != BPF_MAP_TYPE_STRUCT_OPS ||
1086 		    attr->btf_key_type_id || attr->btf_value_type_id)
1087 			return -EINVAL;
1088 	} else if (attr->btf_key_type_id && !attr->btf_value_type_id) {
1089 		return -EINVAL;
1090 	}
1091 
1092 	if (attr->map_type != BPF_MAP_TYPE_BLOOM_FILTER &&
1093 	    attr->map_extra != 0)
1094 		return -EINVAL;
1095 
1096 	f_flags = bpf_get_file_flag(attr->map_flags);
1097 	if (f_flags < 0)
1098 		return f_flags;
1099 
1100 	if (numa_node != NUMA_NO_NODE &&
1101 	    ((unsigned int)numa_node >= nr_node_ids ||
1102 	     !node_online(numa_node)))
1103 		return -EINVAL;
1104 
1105 	/* find map type and init map: hashtable vs rbtree vs bloom vs ... */
1106 	map = find_and_alloc_map(attr);
1107 	if (IS_ERR(map))
1108 		return PTR_ERR(map);
1109 
1110 	err = bpf_obj_name_cpy(map->name, attr->map_name,
1111 			       sizeof(attr->map_name));
1112 	if (err < 0)
1113 		goto free_map;
1114 
1115 	atomic64_set(&map->refcnt, 1);
1116 	atomic64_set(&map->usercnt, 1);
1117 	mutex_init(&map->freeze_mutex);
1118 	spin_lock_init(&map->owner.lock);
1119 
1120 	map->spin_lock_off = -EINVAL;
1121 	map->timer_off = -EINVAL;
1122 	if (attr->btf_key_type_id || attr->btf_value_type_id ||
1123 	    /* Even the map's value is a kernel's struct,
1124 	     * the bpf_prog.o must have BTF to begin with
1125 	     * to figure out the corresponding kernel's
1126 	     * counter part.  Thus, attr->btf_fd has
1127 	     * to be valid also.
1128 	     */
1129 	    attr->btf_vmlinux_value_type_id) {
1130 		struct btf *btf;
1131 
1132 		btf = btf_get_by_fd(attr->btf_fd);
1133 		if (IS_ERR(btf)) {
1134 			err = PTR_ERR(btf);
1135 			goto free_map;
1136 		}
1137 		if (btf_is_kernel(btf)) {
1138 			btf_put(btf);
1139 			err = -EACCES;
1140 			goto free_map;
1141 		}
1142 		map->btf = btf;
1143 
1144 		if (attr->btf_value_type_id) {
1145 			err = map_check_btf(map, btf, attr->btf_key_type_id,
1146 					    attr->btf_value_type_id);
1147 			if (err)
1148 				goto free_map;
1149 		}
1150 
1151 		map->btf_key_type_id = attr->btf_key_type_id;
1152 		map->btf_value_type_id = attr->btf_value_type_id;
1153 		map->btf_vmlinux_value_type_id =
1154 			attr->btf_vmlinux_value_type_id;
1155 	}
1156 
1157 	err = bpf_map_alloc_off_arr(map);
1158 	if (err)
1159 		goto free_map;
1160 
1161 	err = security_bpf_map_alloc(map);
1162 	if (err)
1163 		goto free_map_off_arr;
1164 
1165 	err = bpf_map_alloc_id(map);
1166 	if (err)
1167 		goto free_map_sec;
1168 
1169 	bpf_map_save_memcg(map);
1170 
1171 	err = bpf_map_new_fd(map, f_flags);
1172 	if (err < 0) {
1173 		/* failed to allocate fd.
1174 		 * bpf_map_put_with_uref() is needed because the above
1175 		 * bpf_map_alloc_id() has published the map
1176 		 * to the userspace and the userspace may
1177 		 * have refcnt-ed it through BPF_MAP_GET_FD_BY_ID.
1178 		 */
1179 		bpf_map_put_with_uref(map);
1180 		return err;
1181 	}
1182 
1183 	return err;
1184 
1185 free_map_sec:
1186 	security_bpf_map_free(map);
1187 free_map_off_arr:
1188 	kfree(map->off_arr);
1189 free_map:
1190 	btf_put(map->btf);
1191 	map->ops->map_free(map);
1192 	return err;
1193 }
1194 
1195 /* if error is returned, fd is released.
1196  * On success caller should complete fd access with matching fdput()
1197  */
1198 struct bpf_map *__bpf_map_get(struct fd f)
1199 {
1200 	if (!f.file)
1201 		return ERR_PTR(-EBADF);
1202 	if (f.file->f_op != &bpf_map_fops) {
1203 		fdput(f);
1204 		return ERR_PTR(-EINVAL);
1205 	}
1206 
1207 	return f.file->private_data;
1208 }
1209 
1210 void bpf_map_inc(struct bpf_map *map)
1211 {
1212 	atomic64_inc(&map->refcnt);
1213 }
1214 EXPORT_SYMBOL_GPL(bpf_map_inc);
1215 
1216 void bpf_map_inc_with_uref(struct bpf_map *map)
1217 {
1218 	atomic64_inc(&map->refcnt);
1219 	atomic64_inc(&map->usercnt);
1220 }
1221 EXPORT_SYMBOL_GPL(bpf_map_inc_with_uref);
1222 
1223 struct bpf_map *bpf_map_get(u32 ufd)
1224 {
1225 	struct fd f = fdget(ufd);
1226 	struct bpf_map *map;
1227 
1228 	map = __bpf_map_get(f);
1229 	if (IS_ERR(map))
1230 		return map;
1231 
1232 	bpf_map_inc(map);
1233 	fdput(f);
1234 
1235 	return map;
1236 }
1237 EXPORT_SYMBOL(bpf_map_get);
1238 
1239 struct bpf_map *bpf_map_get_with_uref(u32 ufd)
1240 {
1241 	struct fd f = fdget(ufd);
1242 	struct bpf_map *map;
1243 
1244 	map = __bpf_map_get(f);
1245 	if (IS_ERR(map))
1246 		return map;
1247 
1248 	bpf_map_inc_with_uref(map);
1249 	fdput(f);
1250 
1251 	return map;
1252 }
1253 
1254 /* map_idr_lock should have been held */
1255 static struct bpf_map *__bpf_map_inc_not_zero(struct bpf_map *map, bool uref)
1256 {
1257 	int refold;
1258 
1259 	refold = atomic64_fetch_add_unless(&map->refcnt, 1, 0);
1260 	if (!refold)
1261 		return ERR_PTR(-ENOENT);
1262 	if (uref)
1263 		atomic64_inc(&map->usercnt);
1264 
1265 	return map;
1266 }
1267 
1268 struct bpf_map *bpf_map_inc_not_zero(struct bpf_map *map)
1269 {
1270 	spin_lock_bh(&map_idr_lock);
1271 	map = __bpf_map_inc_not_zero(map, false);
1272 	spin_unlock_bh(&map_idr_lock);
1273 
1274 	return map;
1275 }
1276 EXPORT_SYMBOL_GPL(bpf_map_inc_not_zero);
1277 
1278 int __weak bpf_stackmap_copy(struct bpf_map *map, void *key, void *value)
1279 {
1280 	return -ENOTSUPP;
1281 }
1282 
1283 static void *__bpf_copy_key(void __user *ukey, u64 key_size)
1284 {
1285 	if (key_size)
1286 		return vmemdup_user(ukey, key_size);
1287 
1288 	if (ukey)
1289 		return ERR_PTR(-EINVAL);
1290 
1291 	return NULL;
1292 }
1293 
1294 static void *___bpf_copy_key(bpfptr_t ukey, u64 key_size)
1295 {
1296 	if (key_size)
1297 		return kvmemdup_bpfptr(ukey, key_size);
1298 
1299 	if (!bpfptr_is_null(ukey))
1300 		return ERR_PTR(-EINVAL);
1301 
1302 	return NULL;
1303 }
1304 
1305 /* last field in 'union bpf_attr' used by this command */
1306 #define BPF_MAP_LOOKUP_ELEM_LAST_FIELD flags
1307 
1308 static int map_lookup_elem(union bpf_attr *attr)
1309 {
1310 	void __user *ukey = u64_to_user_ptr(attr->key);
1311 	void __user *uvalue = u64_to_user_ptr(attr->value);
1312 	int ufd = attr->map_fd;
1313 	struct bpf_map *map;
1314 	void *key, *value;
1315 	u32 value_size;
1316 	struct fd f;
1317 	int err;
1318 
1319 	if (CHECK_ATTR(BPF_MAP_LOOKUP_ELEM))
1320 		return -EINVAL;
1321 
1322 	if (attr->flags & ~BPF_F_LOCK)
1323 		return -EINVAL;
1324 
1325 	f = fdget(ufd);
1326 	map = __bpf_map_get(f);
1327 	if (IS_ERR(map))
1328 		return PTR_ERR(map);
1329 	if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) {
1330 		err = -EPERM;
1331 		goto err_put;
1332 	}
1333 
1334 	if ((attr->flags & BPF_F_LOCK) &&
1335 	    !map_value_has_spin_lock(map)) {
1336 		err = -EINVAL;
1337 		goto err_put;
1338 	}
1339 
1340 	key = __bpf_copy_key(ukey, map->key_size);
1341 	if (IS_ERR(key)) {
1342 		err = PTR_ERR(key);
1343 		goto err_put;
1344 	}
1345 
1346 	value_size = bpf_map_value_size(map);
1347 
1348 	err = -ENOMEM;
1349 	value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN);
1350 	if (!value)
1351 		goto free_key;
1352 
1353 	if (map->map_type == BPF_MAP_TYPE_BLOOM_FILTER) {
1354 		if (copy_from_user(value, uvalue, value_size))
1355 			err = -EFAULT;
1356 		else
1357 			err = bpf_map_copy_value(map, key, value, attr->flags);
1358 		goto free_value;
1359 	}
1360 
1361 	err = bpf_map_copy_value(map, key, value, attr->flags);
1362 	if (err)
1363 		goto free_value;
1364 
1365 	err = -EFAULT;
1366 	if (copy_to_user(uvalue, value, value_size) != 0)
1367 		goto free_value;
1368 
1369 	err = 0;
1370 
1371 free_value:
1372 	kvfree(value);
1373 free_key:
1374 	kvfree(key);
1375 err_put:
1376 	fdput(f);
1377 	return err;
1378 }
1379 
1380 
1381 #define BPF_MAP_UPDATE_ELEM_LAST_FIELD flags
1382 
1383 static int map_update_elem(union bpf_attr *attr, bpfptr_t uattr)
1384 {
1385 	bpfptr_t ukey = make_bpfptr(attr->key, uattr.is_kernel);
1386 	bpfptr_t uvalue = make_bpfptr(attr->value, uattr.is_kernel);
1387 	int ufd = attr->map_fd;
1388 	struct bpf_map *map;
1389 	void *key, *value;
1390 	u32 value_size;
1391 	struct fd f;
1392 	int err;
1393 
1394 	if (CHECK_ATTR(BPF_MAP_UPDATE_ELEM))
1395 		return -EINVAL;
1396 
1397 	f = fdget(ufd);
1398 	map = __bpf_map_get(f);
1399 	if (IS_ERR(map))
1400 		return PTR_ERR(map);
1401 	bpf_map_write_active_inc(map);
1402 	if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
1403 		err = -EPERM;
1404 		goto err_put;
1405 	}
1406 
1407 	if ((attr->flags & BPF_F_LOCK) &&
1408 	    !map_value_has_spin_lock(map)) {
1409 		err = -EINVAL;
1410 		goto err_put;
1411 	}
1412 
1413 	key = ___bpf_copy_key(ukey, map->key_size);
1414 	if (IS_ERR(key)) {
1415 		err = PTR_ERR(key);
1416 		goto err_put;
1417 	}
1418 
1419 	value_size = bpf_map_value_size(map);
1420 	value = kvmemdup_bpfptr(uvalue, value_size);
1421 	if (IS_ERR(value)) {
1422 		err = PTR_ERR(value);
1423 		goto free_key;
1424 	}
1425 
1426 	err = bpf_map_update_value(map, f, key, value, attr->flags);
1427 
1428 	kvfree(value);
1429 free_key:
1430 	kvfree(key);
1431 err_put:
1432 	bpf_map_write_active_dec(map);
1433 	fdput(f);
1434 	return err;
1435 }
1436 
1437 #define BPF_MAP_DELETE_ELEM_LAST_FIELD key
1438 
1439 static int map_delete_elem(union bpf_attr *attr, bpfptr_t uattr)
1440 {
1441 	bpfptr_t ukey = make_bpfptr(attr->key, uattr.is_kernel);
1442 	int ufd = attr->map_fd;
1443 	struct bpf_map *map;
1444 	struct fd f;
1445 	void *key;
1446 	int err;
1447 
1448 	if (CHECK_ATTR(BPF_MAP_DELETE_ELEM))
1449 		return -EINVAL;
1450 
1451 	f = fdget(ufd);
1452 	map = __bpf_map_get(f);
1453 	if (IS_ERR(map))
1454 		return PTR_ERR(map);
1455 	bpf_map_write_active_inc(map);
1456 	if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
1457 		err = -EPERM;
1458 		goto err_put;
1459 	}
1460 
1461 	key = ___bpf_copy_key(ukey, map->key_size);
1462 	if (IS_ERR(key)) {
1463 		err = PTR_ERR(key);
1464 		goto err_put;
1465 	}
1466 
1467 	if (bpf_map_is_dev_bound(map)) {
1468 		err = bpf_map_offload_delete_elem(map, key);
1469 		goto out;
1470 	} else if (IS_FD_PROG_ARRAY(map) ||
1471 		   map->map_type == BPF_MAP_TYPE_STRUCT_OPS) {
1472 		/* These maps require sleepable context */
1473 		err = map->ops->map_delete_elem(map, key);
1474 		goto out;
1475 	}
1476 
1477 	bpf_disable_instrumentation();
1478 	rcu_read_lock();
1479 	err = map->ops->map_delete_elem(map, key);
1480 	rcu_read_unlock();
1481 	bpf_enable_instrumentation();
1482 	maybe_wait_bpf_programs(map);
1483 out:
1484 	kvfree(key);
1485 err_put:
1486 	bpf_map_write_active_dec(map);
1487 	fdput(f);
1488 	return err;
1489 }
1490 
1491 /* last field in 'union bpf_attr' used by this command */
1492 #define BPF_MAP_GET_NEXT_KEY_LAST_FIELD next_key
1493 
1494 static int map_get_next_key(union bpf_attr *attr)
1495 {
1496 	void __user *ukey = u64_to_user_ptr(attr->key);
1497 	void __user *unext_key = u64_to_user_ptr(attr->next_key);
1498 	int ufd = attr->map_fd;
1499 	struct bpf_map *map;
1500 	void *key, *next_key;
1501 	struct fd f;
1502 	int err;
1503 
1504 	if (CHECK_ATTR(BPF_MAP_GET_NEXT_KEY))
1505 		return -EINVAL;
1506 
1507 	f = fdget(ufd);
1508 	map = __bpf_map_get(f);
1509 	if (IS_ERR(map))
1510 		return PTR_ERR(map);
1511 	if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) {
1512 		err = -EPERM;
1513 		goto err_put;
1514 	}
1515 
1516 	if (ukey) {
1517 		key = __bpf_copy_key(ukey, map->key_size);
1518 		if (IS_ERR(key)) {
1519 			err = PTR_ERR(key);
1520 			goto err_put;
1521 		}
1522 	} else {
1523 		key = NULL;
1524 	}
1525 
1526 	err = -ENOMEM;
1527 	next_key = kvmalloc(map->key_size, GFP_USER);
1528 	if (!next_key)
1529 		goto free_key;
1530 
1531 	if (bpf_map_is_dev_bound(map)) {
1532 		err = bpf_map_offload_get_next_key(map, key, next_key);
1533 		goto out;
1534 	}
1535 
1536 	rcu_read_lock();
1537 	err = map->ops->map_get_next_key(map, key, next_key);
1538 	rcu_read_unlock();
1539 out:
1540 	if (err)
1541 		goto free_next_key;
1542 
1543 	err = -EFAULT;
1544 	if (copy_to_user(unext_key, next_key, map->key_size) != 0)
1545 		goto free_next_key;
1546 
1547 	err = 0;
1548 
1549 free_next_key:
1550 	kvfree(next_key);
1551 free_key:
1552 	kvfree(key);
1553 err_put:
1554 	fdput(f);
1555 	return err;
1556 }
1557 
1558 int generic_map_delete_batch(struct bpf_map *map,
1559 			     const union bpf_attr *attr,
1560 			     union bpf_attr __user *uattr)
1561 {
1562 	void __user *keys = u64_to_user_ptr(attr->batch.keys);
1563 	u32 cp, max_count;
1564 	int err = 0;
1565 	void *key;
1566 
1567 	if (attr->batch.elem_flags & ~BPF_F_LOCK)
1568 		return -EINVAL;
1569 
1570 	if ((attr->batch.elem_flags & BPF_F_LOCK) &&
1571 	    !map_value_has_spin_lock(map)) {
1572 		return -EINVAL;
1573 	}
1574 
1575 	max_count = attr->batch.count;
1576 	if (!max_count)
1577 		return 0;
1578 
1579 	key = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN);
1580 	if (!key)
1581 		return -ENOMEM;
1582 
1583 	for (cp = 0; cp < max_count; cp++) {
1584 		err = -EFAULT;
1585 		if (copy_from_user(key, keys + cp * map->key_size,
1586 				   map->key_size))
1587 			break;
1588 
1589 		if (bpf_map_is_dev_bound(map)) {
1590 			err = bpf_map_offload_delete_elem(map, key);
1591 			break;
1592 		}
1593 
1594 		bpf_disable_instrumentation();
1595 		rcu_read_lock();
1596 		err = map->ops->map_delete_elem(map, key);
1597 		rcu_read_unlock();
1598 		bpf_enable_instrumentation();
1599 		if (err)
1600 			break;
1601 		cond_resched();
1602 	}
1603 	if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp)))
1604 		err = -EFAULT;
1605 
1606 	kvfree(key);
1607 
1608 	maybe_wait_bpf_programs(map);
1609 	return err;
1610 }
1611 
1612 int generic_map_update_batch(struct bpf_map *map,
1613 			     const union bpf_attr *attr,
1614 			     union bpf_attr __user *uattr)
1615 {
1616 	void __user *values = u64_to_user_ptr(attr->batch.values);
1617 	void __user *keys = u64_to_user_ptr(attr->batch.keys);
1618 	u32 value_size, cp, max_count;
1619 	int ufd = attr->batch.map_fd;
1620 	void *key, *value;
1621 	struct fd f;
1622 	int err = 0;
1623 
1624 	if (attr->batch.elem_flags & ~BPF_F_LOCK)
1625 		return -EINVAL;
1626 
1627 	if ((attr->batch.elem_flags & BPF_F_LOCK) &&
1628 	    !map_value_has_spin_lock(map)) {
1629 		return -EINVAL;
1630 	}
1631 
1632 	value_size = bpf_map_value_size(map);
1633 
1634 	max_count = attr->batch.count;
1635 	if (!max_count)
1636 		return 0;
1637 
1638 	key = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN);
1639 	if (!key)
1640 		return -ENOMEM;
1641 
1642 	value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN);
1643 	if (!value) {
1644 		kvfree(key);
1645 		return -ENOMEM;
1646 	}
1647 
1648 	f = fdget(ufd); /* bpf_map_do_batch() guarantees ufd is valid */
1649 	for (cp = 0; cp < max_count; cp++) {
1650 		err = -EFAULT;
1651 		if (copy_from_user(key, keys + cp * map->key_size,
1652 		    map->key_size) ||
1653 		    copy_from_user(value, values + cp * value_size, value_size))
1654 			break;
1655 
1656 		err = bpf_map_update_value(map, f, key, value,
1657 					   attr->batch.elem_flags);
1658 
1659 		if (err)
1660 			break;
1661 		cond_resched();
1662 	}
1663 
1664 	if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp)))
1665 		err = -EFAULT;
1666 
1667 	kvfree(value);
1668 	kvfree(key);
1669 	fdput(f);
1670 	return err;
1671 }
1672 
1673 #define MAP_LOOKUP_RETRIES 3
1674 
1675 int generic_map_lookup_batch(struct bpf_map *map,
1676 				    const union bpf_attr *attr,
1677 				    union bpf_attr __user *uattr)
1678 {
1679 	void __user *uobatch = u64_to_user_ptr(attr->batch.out_batch);
1680 	void __user *ubatch = u64_to_user_ptr(attr->batch.in_batch);
1681 	void __user *values = u64_to_user_ptr(attr->batch.values);
1682 	void __user *keys = u64_to_user_ptr(attr->batch.keys);
1683 	void *buf, *buf_prevkey, *prev_key, *key, *value;
1684 	int err, retry = MAP_LOOKUP_RETRIES;
1685 	u32 value_size, cp, max_count;
1686 
1687 	if (attr->batch.elem_flags & ~BPF_F_LOCK)
1688 		return -EINVAL;
1689 
1690 	if ((attr->batch.elem_flags & BPF_F_LOCK) &&
1691 	    !map_value_has_spin_lock(map))
1692 		return -EINVAL;
1693 
1694 	value_size = bpf_map_value_size(map);
1695 
1696 	max_count = attr->batch.count;
1697 	if (!max_count)
1698 		return 0;
1699 
1700 	if (put_user(0, &uattr->batch.count))
1701 		return -EFAULT;
1702 
1703 	buf_prevkey = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN);
1704 	if (!buf_prevkey)
1705 		return -ENOMEM;
1706 
1707 	buf = kvmalloc(map->key_size + value_size, GFP_USER | __GFP_NOWARN);
1708 	if (!buf) {
1709 		kvfree(buf_prevkey);
1710 		return -ENOMEM;
1711 	}
1712 
1713 	err = -EFAULT;
1714 	prev_key = NULL;
1715 	if (ubatch && copy_from_user(buf_prevkey, ubatch, map->key_size))
1716 		goto free_buf;
1717 	key = buf;
1718 	value = key + map->key_size;
1719 	if (ubatch)
1720 		prev_key = buf_prevkey;
1721 
1722 	for (cp = 0; cp < max_count;) {
1723 		rcu_read_lock();
1724 		err = map->ops->map_get_next_key(map, prev_key, key);
1725 		rcu_read_unlock();
1726 		if (err)
1727 			break;
1728 		err = bpf_map_copy_value(map, key, value,
1729 					 attr->batch.elem_flags);
1730 
1731 		if (err == -ENOENT) {
1732 			if (retry) {
1733 				retry--;
1734 				continue;
1735 			}
1736 			err = -EINTR;
1737 			break;
1738 		}
1739 
1740 		if (err)
1741 			goto free_buf;
1742 
1743 		if (copy_to_user(keys + cp * map->key_size, key,
1744 				 map->key_size)) {
1745 			err = -EFAULT;
1746 			goto free_buf;
1747 		}
1748 		if (copy_to_user(values + cp * value_size, value, value_size)) {
1749 			err = -EFAULT;
1750 			goto free_buf;
1751 		}
1752 
1753 		if (!prev_key)
1754 			prev_key = buf_prevkey;
1755 
1756 		swap(prev_key, key);
1757 		retry = MAP_LOOKUP_RETRIES;
1758 		cp++;
1759 		cond_resched();
1760 	}
1761 
1762 	if (err == -EFAULT)
1763 		goto free_buf;
1764 
1765 	if ((copy_to_user(&uattr->batch.count, &cp, sizeof(cp)) ||
1766 		    (cp && copy_to_user(uobatch, prev_key, map->key_size))))
1767 		err = -EFAULT;
1768 
1769 free_buf:
1770 	kvfree(buf_prevkey);
1771 	kvfree(buf);
1772 	return err;
1773 }
1774 
1775 #define BPF_MAP_LOOKUP_AND_DELETE_ELEM_LAST_FIELD flags
1776 
1777 static int map_lookup_and_delete_elem(union bpf_attr *attr)
1778 {
1779 	void __user *ukey = u64_to_user_ptr(attr->key);
1780 	void __user *uvalue = u64_to_user_ptr(attr->value);
1781 	int ufd = attr->map_fd;
1782 	struct bpf_map *map;
1783 	void *key, *value;
1784 	u32 value_size;
1785 	struct fd f;
1786 	int err;
1787 
1788 	if (CHECK_ATTR(BPF_MAP_LOOKUP_AND_DELETE_ELEM))
1789 		return -EINVAL;
1790 
1791 	if (attr->flags & ~BPF_F_LOCK)
1792 		return -EINVAL;
1793 
1794 	f = fdget(ufd);
1795 	map = __bpf_map_get(f);
1796 	if (IS_ERR(map))
1797 		return PTR_ERR(map);
1798 	bpf_map_write_active_inc(map);
1799 	if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ) ||
1800 	    !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
1801 		err = -EPERM;
1802 		goto err_put;
1803 	}
1804 
1805 	if (attr->flags &&
1806 	    (map->map_type == BPF_MAP_TYPE_QUEUE ||
1807 	     map->map_type == BPF_MAP_TYPE_STACK)) {
1808 		err = -EINVAL;
1809 		goto err_put;
1810 	}
1811 
1812 	if ((attr->flags & BPF_F_LOCK) &&
1813 	    !map_value_has_spin_lock(map)) {
1814 		err = -EINVAL;
1815 		goto err_put;
1816 	}
1817 
1818 	key = __bpf_copy_key(ukey, map->key_size);
1819 	if (IS_ERR(key)) {
1820 		err = PTR_ERR(key);
1821 		goto err_put;
1822 	}
1823 
1824 	value_size = bpf_map_value_size(map);
1825 
1826 	err = -ENOMEM;
1827 	value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN);
1828 	if (!value)
1829 		goto free_key;
1830 
1831 	err = -ENOTSUPP;
1832 	if (map->map_type == BPF_MAP_TYPE_QUEUE ||
1833 	    map->map_type == BPF_MAP_TYPE_STACK) {
1834 		err = map->ops->map_pop_elem(map, value);
1835 	} else if (map->map_type == BPF_MAP_TYPE_HASH ||
1836 		   map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
1837 		   map->map_type == BPF_MAP_TYPE_LRU_HASH ||
1838 		   map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
1839 		if (!bpf_map_is_dev_bound(map)) {
1840 			bpf_disable_instrumentation();
1841 			rcu_read_lock();
1842 			err = map->ops->map_lookup_and_delete_elem(map, key, value, attr->flags);
1843 			rcu_read_unlock();
1844 			bpf_enable_instrumentation();
1845 		}
1846 	}
1847 
1848 	if (err)
1849 		goto free_value;
1850 
1851 	if (copy_to_user(uvalue, value, value_size) != 0) {
1852 		err = -EFAULT;
1853 		goto free_value;
1854 	}
1855 
1856 	err = 0;
1857 
1858 free_value:
1859 	kvfree(value);
1860 free_key:
1861 	kvfree(key);
1862 err_put:
1863 	bpf_map_write_active_dec(map);
1864 	fdput(f);
1865 	return err;
1866 }
1867 
1868 #define BPF_MAP_FREEZE_LAST_FIELD map_fd
1869 
1870 static int map_freeze(const union bpf_attr *attr)
1871 {
1872 	int err = 0, ufd = attr->map_fd;
1873 	struct bpf_map *map;
1874 	struct fd f;
1875 
1876 	if (CHECK_ATTR(BPF_MAP_FREEZE))
1877 		return -EINVAL;
1878 
1879 	f = fdget(ufd);
1880 	map = __bpf_map_get(f);
1881 	if (IS_ERR(map))
1882 		return PTR_ERR(map);
1883 
1884 	if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS ||
1885 	    map_value_has_timer(map) || map_value_has_kptrs(map)) {
1886 		fdput(f);
1887 		return -ENOTSUPP;
1888 	}
1889 
1890 	mutex_lock(&map->freeze_mutex);
1891 	if (bpf_map_write_active(map)) {
1892 		err = -EBUSY;
1893 		goto err_put;
1894 	}
1895 	if (READ_ONCE(map->frozen)) {
1896 		err = -EBUSY;
1897 		goto err_put;
1898 	}
1899 	if (!bpf_capable()) {
1900 		err = -EPERM;
1901 		goto err_put;
1902 	}
1903 
1904 	WRITE_ONCE(map->frozen, true);
1905 err_put:
1906 	mutex_unlock(&map->freeze_mutex);
1907 	fdput(f);
1908 	return err;
1909 }
1910 
1911 static const struct bpf_prog_ops * const bpf_prog_types[] = {
1912 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) \
1913 	[_id] = & _name ## _prog_ops,
1914 #define BPF_MAP_TYPE(_id, _ops)
1915 #define BPF_LINK_TYPE(_id, _name)
1916 #include <linux/bpf_types.h>
1917 #undef BPF_PROG_TYPE
1918 #undef BPF_MAP_TYPE
1919 #undef BPF_LINK_TYPE
1920 };
1921 
1922 static int find_prog_type(enum bpf_prog_type type, struct bpf_prog *prog)
1923 {
1924 	const struct bpf_prog_ops *ops;
1925 
1926 	if (type >= ARRAY_SIZE(bpf_prog_types))
1927 		return -EINVAL;
1928 	type = array_index_nospec(type, ARRAY_SIZE(bpf_prog_types));
1929 	ops = bpf_prog_types[type];
1930 	if (!ops)
1931 		return -EINVAL;
1932 
1933 	if (!bpf_prog_is_dev_bound(prog->aux))
1934 		prog->aux->ops = ops;
1935 	else
1936 		prog->aux->ops = &bpf_offload_prog_ops;
1937 	prog->type = type;
1938 	return 0;
1939 }
1940 
1941 enum bpf_audit {
1942 	BPF_AUDIT_LOAD,
1943 	BPF_AUDIT_UNLOAD,
1944 	BPF_AUDIT_MAX,
1945 };
1946 
1947 static const char * const bpf_audit_str[BPF_AUDIT_MAX] = {
1948 	[BPF_AUDIT_LOAD]   = "LOAD",
1949 	[BPF_AUDIT_UNLOAD] = "UNLOAD",
1950 };
1951 
1952 static void bpf_audit_prog(const struct bpf_prog *prog, unsigned int op)
1953 {
1954 	struct audit_context *ctx = NULL;
1955 	struct audit_buffer *ab;
1956 
1957 	if (WARN_ON_ONCE(op >= BPF_AUDIT_MAX))
1958 		return;
1959 	if (audit_enabled == AUDIT_OFF)
1960 		return;
1961 	if (op == BPF_AUDIT_LOAD)
1962 		ctx = audit_context();
1963 	ab = audit_log_start(ctx, GFP_ATOMIC, AUDIT_BPF);
1964 	if (unlikely(!ab))
1965 		return;
1966 	audit_log_format(ab, "prog-id=%u op=%s",
1967 			 prog->aux->id, bpf_audit_str[op]);
1968 	audit_log_end(ab);
1969 }
1970 
1971 static int bpf_prog_alloc_id(struct bpf_prog *prog)
1972 {
1973 	int id;
1974 
1975 	idr_preload(GFP_KERNEL);
1976 	spin_lock_bh(&prog_idr_lock);
1977 	id = idr_alloc_cyclic(&prog_idr, prog, 1, INT_MAX, GFP_ATOMIC);
1978 	if (id > 0)
1979 		prog->aux->id = id;
1980 	spin_unlock_bh(&prog_idr_lock);
1981 	idr_preload_end();
1982 
1983 	/* id is in [1, INT_MAX) */
1984 	if (WARN_ON_ONCE(!id))
1985 		return -ENOSPC;
1986 
1987 	return id > 0 ? 0 : id;
1988 }
1989 
1990 void bpf_prog_free_id(struct bpf_prog *prog, bool do_idr_lock)
1991 {
1992 	unsigned long flags;
1993 
1994 	/* cBPF to eBPF migrations are currently not in the idr store.
1995 	 * Offloaded programs are removed from the store when their device
1996 	 * disappears - even if someone grabs an fd to them they are unusable,
1997 	 * simply waiting for refcnt to drop to be freed.
1998 	 */
1999 	if (!prog->aux->id)
2000 		return;
2001 
2002 	if (do_idr_lock)
2003 		spin_lock_irqsave(&prog_idr_lock, flags);
2004 	else
2005 		__acquire(&prog_idr_lock);
2006 
2007 	idr_remove(&prog_idr, prog->aux->id);
2008 	prog->aux->id = 0;
2009 
2010 	if (do_idr_lock)
2011 		spin_unlock_irqrestore(&prog_idr_lock, flags);
2012 	else
2013 		__release(&prog_idr_lock);
2014 }
2015 
2016 static void __bpf_prog_put_rcu(struct rcu_head *rcu)
2017 {
2018 	struct bpf_prog_aux *aux = container_of(rcu, struct bpf_prog_aux, rcu);
2019 
2020 	kvfree(aux->func_info);
2021 	kfree(aux->func_info_aux);
2022 	free_uid(aux->user);
2023 	security_bpf_prog_free(aux);
2024 	bpf_prog_free(aux->prog);
2025 }
2026 
2027 static void __bpf_prog_put_noref(struct bpf_prog *prog, bool deferred)
2028 {
2029 	bpf_prog_kallsyms_del_all(prog);
2030 	btf_put(prog->aux->btf);
2031 	kvfree(prog->aux->jited_linfo);
2032 	kvfree(prog->aux->linfo);
2033 	kfree(prog->aux->kfunc_tab);
2034 	if (prog->aux->attach_btf)
2035 		btf_put(prog->aux->attach_btf);
2036 
2037 	if (deferred) {
2038 		if (prog->aux->sleepable)
2039 			call_rcu_tasks_trace(&prog->aux->rcu, __bpf_prog_put_rcu);
2040 		else
2041 			call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu);
2042 	} else {
2043 		__bpf_prog_put_rcu(&prog->aux->rcu);
2044 	}
2045 }
2046 
2047 static void bpf_prog_put_deferred(struct work_struct *work)
2048 {
2049 	struct bpf_prog_aux *aux;
2050 	struct bpf_prog *prog;
2051 
2052 	aux = container_of(work, struct bpf_prog_aux, work);
2053 	prog = aux->prog;
2054 	perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_UNLOAD, 0);
2055 	bpf_audit_prog(prog, BPF_AUDIT_UNLOAD);
2056 	__bpf_prog_put_noref(prog, true);
2057 }
2058 
2059 static void __bpf_prog_put(struct bpf_prog *prog, bool do_idr_lock)
2060 {
2061 	struct bpf_prog_aux *aux = prog->aux;
2062 
2063 	if (atomic64_dec_and_test(&aux->refcnt)) {
2064 		/* bpf_prog_free_id() must be called first */
2065 		bpf_prog_free_id(prog, do_idr_lock);
2066 
2067 		if (in_irq() || irqs_disabled()) {
2068 			INIT_WORK(&aux->work, bpf_prog_put_deferred);
2069 			schedule_work(&aux->work);
2070 		} else {
2071 			bpf_prog_put_deferred(&aux->work);
2072 		}
2073 	}
2074 }
2075 
2076 void bpf_prog_put(struct bpf_prog *prog)
2077 {
2078 	__bpf_prog_put(prog, true);
2079 }
2080 EXPORT_SYMBOL_GPL(bpf_prog_put);
2081 
2082 static int bpf_prog_release(struct inode *inode, struct file *filp)
2083 {
2084 	struct bpf_prog *prog = filp->private_data;
2085 
2086 	bpf_prog_put(prog);
2087 	return 0;
2088 }
2089 
2090 struct bpf_prog_kstats {
2091 	u64 nsecs;
2092 	u64 cnt;
2093 	u64 misses;
2094 };
2095 
2096 void notrace bpf_prog_inc_misses_counter(struct bpf_prog *prog)
2097 {
2098 	struct bpf_prog_stats *stats;
2099 	unsigned int flags;
2100 
2101 	stats = this_cpu_ptr(prog->stats);
2102 	flags = u64_stats_update_begin_irqsave(&stats->syncp);
2103 	u64_stats_inc(&stats->misses);
2104 	u64_stats_update_end_irqrestore(&stats->syncp, flags);
2105 }
2106 
2107 static void bpf_prog_get_stats(const struct bpf_prog *prog,
2108 			       struct bpf_prog_kstats *stats)
2109 {
2110 	u64 nsecs = 0, cnt = 0, misses = 0;
2111 	int cpu;
2112 
2113 	for_each_possible_cpu(cpu) {
2114 		const struct bpf_prog_stats *st;
2115 		unsigned int start;
2116 		u64 tnsecs, tcnt, tmisses;
2117 
2118 		st = per_cpu_ptr(prog->stats, cpu);
2119 		do {
2120 			start = u64_stats_fetch_begin_irq(&st->syncp);
2121 			tnsecs = u64_stats_read(&st->nsecs);
2122 			tcnt = u64_stats_read(&st->cnt);
2123 			tmisses = u64_stats_read(&st->misses);
2124 		} while (u64_stats_fetch_retry_irq(&st->syncp, start));
2125 		nsecs += tnsecs;
2126 		cnt += tcnt;
2127 		misses += tmisses;
2128 	}
2129 	stats->nsecs = nsecs;
2130 	stats->cnt = cnt;
2131 	stats->misses = misses;
2132 }
2133 
2134 #ifdef CONFIG_PROC_FS
2135 static void bpf_prog_show_fdinfo(struct seq_file *m, struct file *filp)
2136 {
2137 	const struct bpf_prog *prog = filp->private_data;
2138 	char prog_tag[sizeof(prog->tag) * 2 + 1] = { };
2139 	struct bpf_prog_kstats stats;
2140 
2141 	bpf_prog_get_stats(prog, &stats);
2142 	bin2hex(prog_tag, prog->tag, sizeof(prog->tag));
2143 	seq_printf(m,
2144 		   "prog_type:\t%u\n"
2145 		   "prog_jited:\t%u\n"
2146 		   "prog_tag:\t%s\n"
2147 		   "memlock:\t%llu\n"
2148 		   "prog_id:\t%u\n"
2149 		   "run_time_ns:\t%llu\n"
2150 		   "run_cnt:\t%llu\n"
2151 		   "recursion_misses:\t%llu\n"
2152 		   "verified_insns:\t%u\n",
2153 		   prog->type,
2154 		   prog->jited,
2155 		   prog_tag,
2156 		   prog->pages * 1ULL << PAGE_SHIFT,
2157 		   prog->aux->id,
2158 		   stats.nsecs,
2159 		   stats.cnt,
2160 		   stats.misses,
2161 		   prog->aux->verified_insns);
2162 }
2163 #endif
2164 
2165 const struct file_operations bpf_prog_fops = {
2166 #ifdef CONFIG_PROC_FS
2167 	.show_fdinfo	= bpf_prog_show_fdinfo,
2168 #endif
2169 	.release	= bpf_prog_release,
2170 	.read		= bpf_dummy_read,
2171 	.write		= bpf_dummy_write,
2172 };
2173 
2174 int bpf_prog_new_fd(struct bpf_prog *prog)
2175 {
2176 	int ret;
2177 
2178 	ret = security_bpf_prog(prog);
2179 	if (ret < 0)
2180 		return ret;
2181 
2182 	return anon_inode_getfd("bpf-prog", &bpf_prog_fops, prog,
2183 				O_RDWR | O_CLOEXEC);
2184 }
2185 
2186 static struct bpf_prog *____bpf_prog_get(struct fd f)
2187 {
2188 	if (!f.file)
2189 		return ERR_PTR(-EBADF);
2190 	if (f.file->f_op != &bpf_prog_fops) {
2191 		fdput(f);
2192 		return ERR_PTR(-EINVAL);
2193 	}
2194 
2195 	return f.file->private_data;
2196 }
2197 
2198 void bpf_prog_add(struct bpf_prog *prog, int i)
2199 {
2200 	atomic64_add(i, &prog->aux->refcnt);
2201 }
2202 EXPORT_SYMBOL_GPL(bpf_prog_add);
2203 
2204 void bpf_prog_sub(struct bpf_prog *prog, int i)
2205 {
2206 	/* Only to be used for undoing previous bpf_prog_add() in some
2207 	 * error path. We still know that another entity in our call
2208 	 * path holds a reference to the program, thus atomic_sub() can
2209 	 * be safely used in such cases!
2210 	 */
2211 	WARN_ON(atomic64_sub_return(i, &prog->aux->refcnt) == 0);
2212 }
2213 EXPORT_SYMBOL_GPL(bpf_prog_sub);
2214 
2215 void bpf_prog_inc(struct bpf_prog *prog)
2216 {
2217 	atomic64_inc(&prog->aux->refcnt);
2218 }
2219 EXPORT_SYMBOL_GPL(bpf_prog_inc);
2220 
2221 /* prog_idr_lock should have been held */
2222 struct bpf_prog *bpf_prog_inc_not_zero(struct bpf_prog *prog)
2223 {
2224 	int refold;
2225 
2226 	refold = atomic64_fetch_add_unless(&prog->aux->refcnt, 1, 0);
2227 
2228 	if (!refold)
2229 		return ERR_PTR(-ENOENT);
2230 
2231 	return prog;
2232 }
2233 EXPORT_SYMBOL_GPL(bpf_prog_inc_not_zero);
2234 
2235 bool bpf_prog_get_ok(struct bpf_prog *prog,
2236 			    enum bpf_prog_type *attach_type, bool attach_drv)
2237 {
2238 	/* not an attachment, just a refcount inc, always allow */
2239 	if (!attach_type)
2240 		return true;
2241 
2242 	if (prog->type != *attach_type)
2243 		return false;
2244 	if (bpf_prog_is_dev_bound(prog->aux) && !attach_drv)
2245 		return false;
2246 
2247 	return true;
2248 }
2249 
2250 static struct bpf_prog *__bpf_prog_get(u32 ufd, enum bpf_prog_type *attach_type,
2251 				       bool attach_drv)
2252 {
2253 	struct fd f = fdget(ufd);
2254 	struct bpf_prog *prog;
2255 
2256 	prog = ____bpf_prog_get(f);
2257 	if (IS_ERR(prog))
2258 		return prog;
2259 	if (!bpf_prog_get_ok(prog, attach_type, attach_drv)) {
2260 		prog = ERR_PTR(-EINVAL);
2261 		goto out;
2262 	}
2263 
2264 	bpf_prog_inc(prog);
2265 out:
2266 	fdput(f);
2267 	return prog;
2268 }
2269 
2270 struct bpf_prog *bpf_prog_get(u32 ufd)
2271 {
2272 	return __bpf_prog_get(ufd, NULL, false);
2273 }
2274 
2275 struct bpf_prog *bpf_prog_get_type_dev(u32 ufd, enum bpf_prog_type type,
2276 				       bool attach_drv)
2277 {
2278 	return __bpf_prog_get(ufd, &type, attach_drv);
2279 }
2280 EXPORT_SYMBOL_GPL(bpf_prog_get_type_dev);
2281 
2282 /* Initially all BPF programs could be loaded w/o specifying
2283  * expected_attach_type. Later for some of them specifying expected_attach_type
2284  * at load time became required so that program could be validated properly.
2285  * Programs of types that are allowed to be loaded both w/ and w/o (for
2286  * backward compatibility) expected_attach_type, should have the default attach
2287  * type assigned to expected_attach_type for the latter case, so that it can be
2288  * validated later at attach time.
2289  *
2290  * bpf_prog_load_fixup_attach_type() sets expected_attach_type in @attr if
2291  * prog type requires it but has some attach types that have to be backward
2292  * compatible.
2293  */
2294 static void bpf_prog_load_fixup_attach_type(union bpf_attr *attr)
2295 {
2296 	switch (attr->prog_type) {
2297 	case BPF_PROG_TYPE_CGROUP_SOCK:
2298 		/* Unfortunately BPF_ATTACH_TYPE_UNSPEC enumeration doesn't
2299 		 * exist so checking for non-zero is the way to go here.
2300 		 */
2301 		if (!attr->expected_attach_type)
2302 			attr->expected_attach_type =
2303 				BPF_CGROUP_INET_SOCK_CREATE;
2304 		break;
2305 	case BPF_PROG_TYPE_SK_REUSEPORT:
2306 		if (!attr->expected_attach_type)
2307 			attr->expected_attach_type =
2308 				BPF_SK_REUSEPORT_SELECT;
2309 		break;
2310 	}
2311 }
2312 
2313 static int
2314 bpf_prog_load_check_attach(enum bpf_prog_type prog_type,
2315 			   enum bpf_attach_type expected_attach_type,
2316 			   struct btf *attach_btf, u32 btf_id,
2317 			   struct bpf_prog *dst_prog)
2318 {
2319 	if (btf_id) {
2320 		if (btf_id > BTF_MAX_TYPE)
2321 			return -EINVAL;
2322 
2323 		if (!attach_btf && !dst_prog)
2324 			return -EINVAL;
2325 
2326 		switch (prog_type) {
2327 		case BPF_PROG_TYPE_TRACING:
2328 		case BPF_PROG_TYPE_LSM:
2329 		case BPF_PROG_TYPE_STRUCT_OPS:
2330 		case BPF_PROG_TYPE_EXT:
2331 			break;
2332 		default:
2333 			return -EINVAL;
2334 		}
2335 	}
2336 
2337 	if (attach_btf && (!btf_id || dst_prog))
2338 		return -EINVAL;
2339 
2340 	if (dst_prog && prog_type != BPF_PROG_TYPE_TRACING &&
2341 	    prog_type != BPF_PROG_TYPE_EXT)
2342 		return -EINVAL;
2343 
2344 	switch (prog_type) {
2345 	case BPF_PROG_TYPE_CGROUP_SOCK:
2346 		switch (expected_attach_type) {
2347 		case BPF_CGROUP_INET_SOCK_CREATE:
2348 		case BPF_CGROUP_INET_SOCK_RELEASE:
2349 		case BPF_CGROUP_INET4_POST_BIND:
2350 		case BPF_CGROUP_INET6_POST_BIND:
2351 			return 0;
2352 		default:
2353 			return -EINVAL;
2354 		}
2355 	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
2356 		switch (expected_attach_type) {
2357 		case BPF_CGROUP_INET4_BIND:
2358 		case BPF_CGROUP_INET6_BIND:
2359 		case BPF_CGROUP_INET4_CONNECT:
2360 		case BPF_CGROUP_INET6_CONNECT:
2361 		case BPF_CGROUP_INET4_GETPEERNAME:
2362 		case BPF_CGROUP_INET6_GETPEERNAME:
2363 		case BPF_CGROUP_INET4_GETSOCKNAME:
2364 		case BPF_CGROUP_INET6_GETSOCKNAME:
2365 		case BPF_CGROUP_UDP4_SENDMSG:
2366 		case BPF_CGROUP_UDP6_SENDMSG:
2367 		case BPF_CGROUP_UDP4_RECVMSG:
2368 		case BPF_CGROUP_UDP6_RECVMSG:
2369 			return 0;
2370 		default:
2371 			return -EINVAL;
2372 		}
2373 	case BPF_PROG_TYPE_CGROUP_SKB:
2374 		switch (expected_attach_type) {
2375 		case BPF_CGROUP_INET_INGRESS:
2376 		case BPF_CGROUP_INET_EGRESS:
2377 			return 0;
2378 		default:
2379 			return -EINVAL;
2380 		}
2381 	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
2382 		switch (expected_attach_type) {
2383 		case BPF_CGROUP_SETSOCKOPT:
2384 		case BPF_CGROUP_GETSOCKOPT:
2385 			return 0;
2386 		default:
2387 			return -EINVAL;
2388 		}
2389 	case BPF_PROG_TYPE_SK_LOOKUP:
2390 		if (expected_attach_type == BPF_SK_LOOKUP)
2391 			return 0;
2392 		return -EINVAL;
2393 	case BPF_PROG_TYPE_SK_REUSEPORT:
2394 		switch (expected_attach_type) {
2395 		case BPF_SK_REUSEPORT_SELECT:
2396 		case BPF_SK_REUSEPORT_SELECT_OR_MIGRATE:
2397 			return 0;
2398 		default:
2399 			return -EINVAL;
2400 		}
2401 	case BPF_PROG_TYPE_SYSCALL:
2402 	case BPF_PROG_TYPE_EXT:
2403 		if (expected_attach_type)
2404 			return -EINVAL;
2405 		fallthrough;
2406 	default:
2407 		return 0;
2408 	}
2409 }
2410 
2411 static bool is_net_admin_prog_type(enum bpf_prog_type prog_type)
2412 {
2413 	switch (prog_type) {
2414 	case BPF_PROG_TYPE_SCHED_CLS:
2415 	case BPF_PROG_TYPE_SCHED_ACT:
2416 	case BPF_PROG_TYPE_XDP:
2417 	case BPF_PROG_TYPE_LWT_IN:
2418 	case BPF_PROG_TYPE_LWT_OUT:
2419 	case BPF_PROG_TYPE_LWT_XMIT:
2420 	case BPF_PROG_TYPE_LWT_SEG6LOCAL:
2421 	case BPF_PROG_TYPE_SK_SKB:
2422 	case BPF_PROG_TYPE_SK_MSG:
2423 	case BPF_PROG_TYPE_LIRC_MODE2:
2424 	case BPF_PROG_TYPE_FLOW_DISSECTOR:
2425 	case BPF_PROG_TYPE_CGROUP_DEVICE:
2426 	case BPF_PROG_TYPE_CGROUP_SOCK:
2427 	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
2428 	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
2429 	case BPF_PROG_TYPE_CGROUP_SYSCTL:
2430 	case BPF_PROG_TYPE_SOCK_OPS:
2431 	case BPF_PROG_TYPE_EXT: /* extends any prog */
2432 		return true;
2433 	case BPF_PROG_TYPE_CGROUP_SKB:
2434 		/* always unpriv */
2435 	case BPF_PROG_TYPE_SK_REUSEPORT:
2436 		/* equivalent to SOCKET_FILTER. need CAP_BPF only */
2437 	default:
2438 		return false;
2439 	}
2440 }
2441 
2442 static bool is_perfmon_prog_type(enum bpf_prog_type prog_type)
2443 {
2444 	switch (prog_type) {
2445 	case BPF_PROG_TYPE_KPROBE:
2446 	case BPF_PROG_TYPE_TRACEPOINT:
2447 	case BPF_PROG_TYPE_PERF_EVENT:
2448 	case BPF_PROG_TYPE_RAW_TRACEPOINT:
2449 	case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE:
2450 	case BPF_PROG_TYPE_TRACING:
2451 	case BPF_PROG_TYPE_LSM:
2452 	case BPF_PROG_TYPE_STRUCT_OPS: /* has access to struct sock */
2453 	case BPF_PROG_TYPE_EXT: /* extends any prog */
2454 		return true;
2455 	default:
2456 		return false;
2457 	}
2458 }
2459 
2460 /* last field in 'union bpf_attr' used by this command */
2461 #define	BPF_PROG_LOAD_LAST_FIELD core_relo_rec_size
2462 
2463 static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr)
2464 {
2465 	enum bpf_prog_type type = attr->prog_type;
2466 	struct bpf_prog *prog, *dst_prog = NULL;
2467 	struct btf *attach_btf = NULL;
2468 	int err;
2469 	char license[128];
2470 	bool is_gpl;
2471 
2472 	if (CHECK_ATTR(BPF_PROG_LOAD))
2473 		return -EINVAL;
2474 
2475 	if (attr->prog_flags & ~(BPF_F_STRICT_ALIGNMENT |
2476 				 BPF_F_ANY_ALIGNMENT |
2477 				 BPF_F_TEST_STATE_FREQ |
2478 				 BPF_F_SLEEPABLE |
2479 				 BPF_F_TEST_RND_HI32 |
2480 				 BPF_F_XDP_HAS_FRAGS))
2481 		return -EINVAL;
2482 
2483 	if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) &&
2484 	    (attr->prog_flags & BPF_F_ANY_ALIGNMENT) &&
2485 	    !bpf_capable())
2486 		return -EPERM;
2487 
2488 	/* copy eBPF program license from user space */
2489 	if (strncpy_from_bpfptr(license,
2490 				make_bpfptr(attr->license, uattr.is_kernel),
2491 				sizeof(license) - 1) < 0)
2492 		return -EFAULT;
2493 	license[sizeof(license) - 1] = 0;
2494 
2495 	/* eBPF programs must be GPL compatible to use GPL-ed functions */
2496 	is_gpl = license_is_gpl_compatible(license);
2497 
2498 	if (attr->insn_cnt == 0 ||
2499 	    attr->insn_cnt > (bpf_capable() ? BPF_COMPLEXITY_LIMIT_INSNS : BPF_MAXINSNS))
2500 		return -E2BIG;
2501 	if (type != BPF_PROG_TYPE_SOCKET_FILTER &&
2502 	    type != BPF_PROG_TYPE_CGROUP_SKB &&
2503 	    !bpf_capable())
2504 		return -EPERM;
2505 
2506 	if (is_net_admin_prog_type(type) && !capable(CAP_NET_ADMIN) && !capable(CAP_SYS_ADMIN))
2507 		return -EPERM;
2508 	if (is_perfmon_prog_type(type) && !perfmon_capable())
2509 		return -EPERM;
2510 
2511 	/* attach_prog_fd/attach_btf_obj_fd can specify fd of either bpf_prog
2512 	 * or btf, we need to check which one it is
2513 	 */
2514 	if (attr->attach_prog_fd) {
2515 		dst_prog = bpf_prog_get(attr->attach_prog_fd);
2516 		if (IS_ERR(dst_prog)) {
2517 			dst_prog = NULL;
2518 			attach_btf = btf_get_by_fd(attr->attach_btf_obj_fd);
2519 			if (IS_ERR(attach_btf))
2520 				return -EINVAL;
2521 			if (!btf_is_kernel(attach_btf)) {
2522 				/* attaching through specifying bpf_prog's BTF
2523 				 * objects directly might be supported eventually
2524 				 */
2525 				btf_put(attach_btf);
2526 				return -ENOTSUPP;
2527 			}
2528 		}
2529 	} else if (attr->attach_btf_id) {
2530 		/* fall back to vmlinux BTF, if BTF type ID is specified */
2531 		attach_btf = bpf_get_btf_vmlinux();
2532 		if (IS_ERR(attach_btf))
2533 			return PTR_ERR(attach_btf);
2534 		if (!attach_btf)
2535 			return -EINVAL;
2536 		btf_get(attach_btf);
2537 	}
2538 
2539 	bpf_prog_load_fixup_attach_type(attr);
2540 	if (bpf_prog_load_check_attach(type, attr->expected_attach_type,
2541 				       attach_btf, attr->attach_btf_id,
2542 				       dst_prog)) {
2543 		if (dst_prog)
2544 			bpf_prog_put(dst_prog);
2545 		if (attach_btf)
2546 			btf_put(attach_btf);
2547 		return -EINVAL;
2548 	}
2549 
2550 	/* plain bpf_prog allocation */
2551 	prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER);
2552 	if (!prog) {
2553 		if (dst_prog)
2554 			bpf_prog_put(dst_prog);
2555 		if (attach_btf)
2556 			btf_put(attach_btf);
2557 		return -ENOMEM;
2558 	}
2559 
2560 	prog->expected_attach_type = attr->expected_attach_type;
2561 	prog->aux->attach_btf = attach_btf;
2562 	prog->aux->attach_btf_id = attr->attach_btf_id;
2563 	prog->aux->dst_prog = dst_prog;
2564 	prog->aux->offload_requested = !!attr->prog_ifindex;
2565 	prog->aux->sleepable = attr->prog_flags & BPF_F_SLEEPABLE;
2566 	prog->aux->xdp_has_frags = attr->prog_flags & BPF_F_XDP_HAS_FRAGS;
2567 
2568 	err = security_bpf_prog_alloc(prog->aux);
2569 	if (err)
2570 		goto free_prog;
2571 
2572 	prog->aux->user = get_current_user();
2573 	prog->len = attr->insn_cnt;
2574 
2575 	err = -EFAULT;
2576 	if (copy_from_bpfptr(prog->insns,
2577 			     make_bpfptr(attr->insns, uattr.is_kernel),
2578 			     bpf_prog_insn_size(prog)) != 0)
2579 		goto free_prog_sec;
2580 
2581 	prog->orig_prog = NULL;
2582 	prog->jited = 0;
2583 
2584 	atomic64_set(&prog->aux->refcnt, 1);
2585 	prog->gpl_compatible = is_gpl ? 1 : 0;
2586 
2587 	if (bpf_prog_is_dev_bound(prog->aux)) {
2588 		err = bpf_prog_offload_init(prog, attr);
2589 		if (err)
2590 			goto free_prog_sec;
2591 	}
2592 
2593 	/* find program type: socket_filter vs tracing_filter */
2594 	err = find_prog_type(type, prog);
2595 	if (err < 0)
2596 		goto free_prog_sec;
2597 
2598 	prog->aux->load_time = ktime_get_boottime_ns();
2599 	err = bpf_obj_name_cpy(prog->aux->name, attr->prog_name,
2600 			       sizeof(attr->prog_name));
2601 	if (err < 0)
2602 		goto free_prog_sec;
2603 
2604 	/* run eBPF verifier */
2605 	err = bpf_check(&prog, attr, uattr);
2606 	if (err < 0)
2607 		goto free_used_maps;
2608 
2609 	prog = bpf_prog_select_runtime(prog, &err);
2610 	if (err < 0)
2611 		goto free_used_maps;
2612 
2613 	err = bpf_prog_alloc_id(prog);
2614 	if (err)
2615 		goto free_used_maps;
2616 
2617 	/* Upon success of bpf_prog_alloc_id(), the BPF prog is
2618 	 * effectively publicly exposed. However, retrieving via
2619 	 * bpf_prog_get_fd_by_id() will take another reference,
2620 	 * therefore it cannot be gone underneath us.
2621 	 *
2622 	 * Only for the time /after/ successful bpf_prog_new_fd()
2623 	 * and before returning to userspace, we might just hold
2624 	 * one reference and any parallel close on that fd could
2625 	 * rip everything out. Hence, below notifications must
2626 	 * happen before bpf_prog_new_fd().
2627 	 *
2628 	 * Also, any failure handling from this point onwards must
2629 	 * be using bpf_prog_put() given the program is exposed.
2630 	 */
2631 	bpf_prog_kallsyms_add(prog);
2632 	perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_LOAD, 0);
2633 	bpf_audit_prog(prog, BPF_AUDIT_LOAD);
2634 
2635 	err = bpf_prog_new_fd(prog);
2636 	if (err < 0)
2637 		bpf_prog_put(prog);
2638 	return err;
2639 
2640 free_used_maps:
2641 	/* In case we have subprogs, we need to wait for a grace
2642 	 * period before we can tear down JIT memory since symbols
2643 	 * are already exposed under kallsyms.
2644 	 */
2645 	__bpf_prog_put_noref(prog, prog->aux->func_cnt);
2646 	return err;
2647 free_prog_sec:
2648 	free_uid(prog->aux->user);
2649 	security_bpf_prog_free(prog->aux);
2650 free_prog:
2651 	if (prog->aux->attach_btf)
2652 		btf_put(prog->aux->attach_btf);
2653 	bpf_prog_free(prog);
2654 	return err;
2655 }
2656 
2657 #define BPF_OBJ_LAST_FIELD file_flags
2658 
2659 static int bpf_obj_pin(const union bpf_attr *attr)
2660 {
2661 	if (CHECK_ATTR(BPF_OBJ) || attr->file_flags != 0)
2662 		return -EINVAL;
2663 
2664 	return bpf_obj_pin_user(attr->bpf_fd, u64_to_user_ptr(attr->pathname));
2665 }
2666 
2667 static int bpf_obj_get(const union bpf_attr *attr)
2668 {
2669 	if (CHECK_ATTR(BPF_OBJ) || attr->bpf_fd != 0 ||
2670 	    attr->file_flags & ~BPF_OBJ_FLAG_MASK)
2671 		return -EINVAL;
2672 
2673 	return bpf_obj_get_user(u64_to_user_ptr(attr->pathname),
2674 				attr->file_flags);
2675 }
2676 
2677 void bpf_link_init(struct bpf_link *link, enum bpf_link_type type,
2678 		   const struct bpf_link_ops *ops, struct bpf_prog *prog)
2679 {
2680 	atomic64_set(&link->refcnt, 1);
2681 	link->type = type;
2682 	link->id = 0;
2683 	link->ops = ops;
2684 	link->prog = prog;
2685 }
2686 
2687 static void bpf_link_free_id(int id)
2688 {
2689 	if (!id)
2690 		return;
2691 
2692 	spin_lock_bh(&link_idr_lock);
2693 	idr_remove(&link_idr, id);
2694 	spin_unlock_bh(&link_idr_lock);
2695 }
2696 
2697 /* Clean up bpf_link and corresponding anon_inode file and FD. After
2698  * anon_inode is created, bpf_link can't be just kfree()'d due to deferred
2699  * anon_inode's release() call. This helper marksbpf_link as
2700  * defunct, releases anon_inode file and puts reserved FD. bpf_prog's refcnt
2701  * is not decremented, it's the responsibility of a calling code that failed
2702  * to complete bpf_link initialization.
2703  */
2704 void bpf_link_cleanup(struct bpf_link_primer *primer)
2705 {
2706 	primer->link->prog = NULL;
2707 	bpf_link_free_id(primer->id);
2708 	fput(primer->file);
2709 	put_unused_fd(primer->fd);
2710 }
2711 
2712 void bpf_link_inc(struct bpf_link *link)
2713 {
2714 	atomic64_inc(&link->refcnt);
2715 }
2716 
2717 /* bpf_link_free is guaranteed to be called from process context */
2718 static void bpf_link_free(struct bpf_link *link)
2719 {
2720 	bpf_link_free_id(link->id);
2721 	if (link->prog) {
2722 		/* detach BPF program, clean up used resources */
2723 		link->ops->release(link);
2724 		bpf_prog_put(link->prog);
2725 	}
2726 	/* free bpf_link and its containing memory */
2727 	link->ops->dealloc(link);
2728 }
2729 
2730 static void bpf_link_put_deferred(struct work_struct *work)
2731 {
2732 	struct bpf_link *link = container_of(work, struct bpf_link, work);
2733 
2734 	bpf_link_free(link);
2735 }
2736 
2737 /* bpf_link_put can be called from atomic context, but ensures that resources
2738  * are freed from process context
2739  */
2740 void bpf_link_put(struct bpf_link *link)
2741 {
2742 	if (!atomic64_dec_and_test(&link->refcnt))
2743 		return;
2744 
2745 	if (in_atomic()) {
2746 		INIT_WORK(&link->work, bpf_link_put_deferred);
2747 		schedule_work(&link->work);
2748 	} else {
2749 		bpf_link_free(link);
2750 	}
2751 }
2752 EXPORT_SYMBOL(bpf_link_put);
2753 
2754 static int bpf_link_release(struct inode *inode, struct file *filp)
2755 {
2756 	struct bpf_link *link = filp->private_data;
2757 
2758 	bpf_link_put(link);
2759 	return 0;
2760 }
2761 
2762 #ifdef CONFIG_PROC_FS
2763 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type)
2764 #define BPF_MAP_TYPE(_id, _ops)
2765 #define BPF_LINK_TYPE(_id, _name) [_id] = #_name,
2766 static const char *bpf_link_type_strs[] = {
2767 	[BPF_LINK_TYPE_UNSPEC] = "<invalid>",
2768 #include <linux/bpf_types.h>
2769 };
2770 #undef BPF_PROG_TYPE
2771 #undef BPF_MAP_TYPE
2772 #undef BPF_LINK_TYPE
2773 
2774 static void bpf_link_show_fdinfo(struct seq_file *m, struct file *filp)
2775 {
2776 	const struct bpf_link *link = filp->private_data;
2777 	const struct bpf_prog *prog = link->prog;
2778 	char prog_tag[sizeof(prog->tag) * 2 + 1] = { };
2779 
2780 	bin2hex(prog_tag, prog->tag, sizeof(prog->tag));
2781 	seq_printf(m,
2782 		   "link_type:\t%s\n"
2783 		   "link_id:\t%u\n"
2784 		   "prog_tag:\t%s\n"
2785 		   "prog_id:\t%u\n",
2786 		   bpf_link_type_strs[link->type],
2787 		   link->id,
2788 		   prog_tag,
2789 		   prog->aux->id);
2790 	if (link->ops->show_fdinfo)
2791 		link->ops->show_fdinfo(link, m);
2792 }
2793 #endif
2794 
2795 static const struct file_operations bpf_link_fops = {
2796 #ifdef CONFIG_PROC_FS
2797 	.show_fdinfo	= bpf_link_show_fdinfo,
2798 #endif
2799 	.release	= bpf_link_release,
2800 	.read		= bpf_dummy_read,
2801 	.write		= bpf_dummy_write,
2802 };
2803 
2804 static int bpf_link_alloc_id(struct bpf_link *link)
2805 {
2806 	int id;
2807 
2808 	idr_preload(GFP_KERNEL);
2809 	spin_lock_bh(&link_idr_lock);
2810 	id = idr_alloc_cyclic(&link_idr, link, 1, INT_MAX, GFP_ATOMIC);
2811 	spin_unlock_bh(&link_idr_lock);
2812 	idr_preload_end();
2813 
2814 	return id;
2815 }
2816 
2817 /* Prepare bpf_link to be exposed to user-space by allocating anon_inode file,
2818  * reserving unused FD and allocating ID from link_idr. This is to be paired
2819  * with bpf_link_settle() to install FD and ID and expose bpf_link to
2820  * user-space, if bpf_link is successfully attached. If not, bpf_link and
2821  * pre-allocated resources are to be freed with bpf_cleanup() call. All the
2822  * transient state is passed around in struct bpf_link_primer.
2823  * This is preferred way to create and initialize bpf_link, especially when
2824  * there are complicated and expensive operations in between creating bpf_link
2825  * itself and attaching it to BPF hook. By using bpf_link_prime() and
2826  * bpf_link_settle() kernel code using bpf_link doesn't have to perform
2827  * expensive (and potentially failing) roll back operations in a rare case
2828  * that file, FD, or ID can't be allocated.
2829  */
2830 int bpf_link_prime(struct bpf_link *link, struct bpf_link_primer *primer)
2831 {
2832 	struct file *file;
2833 	int fd, id;
2834 
2835 	fd = get_unused_fd_flags(O_CLOEXEC);
2836 	if (fd < 0)
2837 		return fd;
2838 
2839 
2840 	id = bpf_link_alloc_id(link);
2841 	if (id < 0) {
2842 		put_unused_fd(fd);
2843 		return id;
2844 	}
2845 
2846 	file = anon_inode_getfile("bpf_link", &bpf_link_fops, link, O_CLOEXEC);
2847 	if (IS_ERR(file)) {
2848 		bpf_link_free_id(id);
2849 		put_unused_fd(fd);
2850 		return PTR_ERR(file);
2851 	}
2852 
2853 	primer->link = link;
2854 	primer->file = file;
2855 	primer->fd = fd;
2856 	primer->id = id;
2857 	return 0;
2858 }
2859 
2860 int bpf_link_settle(struct bpf_link_primer *primer)
2861 {
2862 	/* make bpf_link fetchable by ID */
2863 	spin_lock_bh(&link_idr_lock);
2864 	primer->link->id = primer->id;
2865 	spin_unlock_bh(&link_idr_lock);
2866 	/* make bpf_link fetchable by FD */
2867 	fd_install(primer->fd, primer->file);
2868 	/* pass through installed FD */
2869 	return primer->fd;
2870 }
2871 
2872 int bpf_link_new_fd(struct bpf_link *link)
2873 {
2874 	return anon_inode_getfd("bpf-link", &bpf_link_fops, link, O_CLOEXEC);
2875 }
2876 
2877 struct bpf_link *bpf_link_get_from_fd(u32 ufd)
2878 {
2879 	struct fd f = fdget(ufd);
2880 	struct bpf_link *link;
2881 
2882 	if (!f.file)
2883 		return ERR_PTR(-EBADF);
2884 	if (f.file->f_op != &bpf_link_fops) {
2885 		fdput(f);
2886 		return ERR_PTR(-EINVAL);
2887 	}
2888 
2889 	link = f.file->private_data;
2890 	bpf_link_inc(link);
2891 	fdput(f);
2892 
2893 	return link;
2894 }
2895 EXPORT_SYMBOL(bpf_link_get_from_fd);
2896 
2897 static void bpf_tracing_link_release(struct bpf_link *link)
2898 {
2899 	struct bpf_tracing_link *tr_link =
2900 		container_of(link, struct bpf_tracing_link, link.link);
2901 
2902 	WARN_ON_ONCE(bpf_trampoline_unlink_prog(&tr_link->link,
2903 						tr_link->trampoline));
2904 
2905 	bpf_trampoline_put(tr_link->trampoline);
2906 
2907 	/* tgt_prog is NULL if target is a kernel function */
2908 	if (tr_link->tgt_prog)
2909 		bpf_prog_put(tr_link->tgt_prog);
2910 }
2911 
2912 static void bpf_tracing_link_dealloc(struct bpf_link *link)
2913 {
2914 	struct bpf_tracing_link *tr_link =
2915 		container_of(link, struct bpf_tracing_link, link.link);
2916 
2917 	kfree(tr_link);
2918 }
2919 
2920 static void bpf_tracing_link_show_fdinfo(const struct bpf_link *link,
2921 					 struct seq_file *seq)
2922 {
2923 	struct bpf_tracing_link *tr_link =
2924 		container_of(link, struct bpf_tracing_link, link.link);
2925 
2926 	seq_printf(seq,
2927 		   "attach_type:\t%d\n",
2928 		   tr_link->attach_type);
2929 }
2930 
2931 static int bpf_tracing_link_fill_link_info(const struct bpf_link *link,
2932 					   struct bpf_link_info *info)
2933 {
2934 	struct bpf_tracing_link *tr_link =
2935 		container_of(link, struct bpf_tracing_link, link.link);
2936 
2937 	info->tracing.attach_type = tr_link->attach_type;
2938 	bpf_trampoline_unpack_key(tr_link->trampoline->key,
2939 				  &info->tracing.target_obj_id,
2940 				  &info->tracing.target_btf_id);
2941 
2942 	return 0;
2943 }
2944 
2945 static const struct bpf_link_ops bpf_tracing_link_lops = {
2946 	.release = bpf_tracing_link_release,
2947 	.dealloc = bpf_tracing_link_dealloc,
2948 	.show_fdinfo = bpf_tracing_link_show_fdinfo,
2949 	.fill_link_info = bpf_tracing_link_fill_link_info,
2950 };
2951 
2952 static int bpf_tracing_prog_attach(struct bpf_prog *prog,
2953 				   int tgt_prog_fd,
2954 				   u32 btf_id,
2955 				   u64 bpf_cookie)
2956 {
2957 	struct bpf_link_primer link_primer;
2958 	struct bpf_prog *tgt_prog = NULL;
2959 	struct bpf_trampoline *tr = NULL;
2960 	struct bpf_tracing_link *link;
2961 	u64 key = 0;
2962 	int err;
2963 
2964 	switch (prog->type) {
2965 	case BPF_PROG_TYPE_TRACING:
2966 		if (prog->expected_attach_type != BPF_TRACE_FENTRY &&
2967 		    prog->expected_attach_type != BPF_TRACE_FEXIT &&
2968 		    prog->expected_attach_type != BPF_MODIFY_RETURN) {
2969 			err = -EINVAL;
2970 			goto out_put_prog;
2971 		}
2972 		break;
2973 	case BPF_PROG_TYPE_EXT:
2974 		if (prog->expected_attach_type != 0) {
2975 			err = -EINVAL;
2976 			goto out_put_prog;
2977 		}
2978 		break;
2979 	case BPF_PROG_TYPE_LSM:
2980 		if (prog->expected_attach_type != BPF_LSM_MAC) {
2981 			err = -EINVAL;
2982 			goto out_put_prog;
2983 		}
2984 		break;
2985 	default:
2986 		err = -EINVAL;
2987 		goto out_put_prog;
2988 	}
2989 
2990 	if (!!tgt_prog_fd != !!btf_id) {
2991 		err = -EINVAL;
2992 		goto out_put_prog;
2993 	}
2994 
2995 	if (tgt_prog_fd) {
2996 		/* For now we only allow new targets for BPF_PROG_TYPE_EXT */
2997 		if (prog->type != BPF_PROG_TYPE_EXT) {
2998 			err = -EINVAL;
2999 			goto out_put_prog;
3000 		}
3001 
3002 		tgt_prog = bpf_prog_get(tgt_prog_fd);
3003 		if (IS_ERR(tgt_prog)) {
3004 			err = PTR_ERR(tgt_prog);
3005 			tgt_prog = NULL;
3006 			goto out_put_prog;
3007 		}
3008 
3009 		key = bpf_trampoline_compute_key(tgt_prog, NULL, btf_id);
3010 	}
3011 
3012 	link = kzalloc(sizeof(*link), GFP_USER);
3013 	if (!link) {
3014 		err = -ENOMEM;
3015 		goto out_put_prog;
3016 	}
3017 	bpf_link_init(&link->link.link, BPF_LINK_TYPE_TRACING,
3018 		      &bpf_tracing_link_lops, prog);
3019 	link->attach_type = prog->expected_attach_type;
3020 	link->link.cookie = bpf_cookie;
3021 
3022 	mutex_lock(&prog->aux->dst_mutex);
3023 
3024 	/* There are a few possible cases here:
3025 	 *
3026 	 * - if prog->aux->dst_trampoline is set, the program was just loaded
3027 	 *   and not yet attached to anything, so we can use the values stored
3028 	 *   in prog->aux
3029 	 *
3030 	 * - if prog->aux->dst_trampoline is NULL, the program has already been
3031          *   attached to a target and its initial target was cleared (below)
3032 	 *
3033 	 * - if tgt_prog != NULL, the caller specified tgt_prog_fd +
3034 	 *   target_btf_id using the link_create API.
3035 	 *
3036 	 * - if tgt_prog == NULL when this function was called using the old
3037 	 *   raw_tracepoint_open API, and we need a target from prog->aux
3038 	 *
3039 	 * - if prog->aux->dst_trampoline and tgt_prog is NULL, the program
3040 	 *   was detached and is going for re-attachment.
3041 	 */
3042 	if (!prog->aux->dst_trampoline && !tgt_prog) {
3043 		/*
3044 		 * Allow re-attach for TRACING and LSM programs. If it's
3045 		 * currently linked, bpf_trampoline_link_prog will fail.
3046 		 * EXT programs need to specify tgt_prog_fd, so they
3047 		 * re-attach in separate code path.
3048 		 */
3049 		if (prog->type != BPF_PROG_TYPE_TRACING &&
3050 		    prog->type != BPF_PROG_TYPE_LSM) {
3051 			err = -EINVAL;
3052 			goto out_unlock;
3053 		}
3054 		btf_id = prog->aux->attach_btf_id;
3055 		key = bpf_trampoline_compute_key(NULL, prog->aux->attach_btf, btf_id);
3056 	}
3057 
3058 	if (!prog->aux->dst_trampoline ||
3059 	    (key && key != prog->aux->dst_trampoline->key)) {
3060 		/* If there is no saved target, or the specified target is
3061 		 * different from the destination specified at load time, we
3062 		 * need a new trampoline and a check for compatibility
3063 		 */
3064 		struct bpf_attach_target_info tgt_info = {};
3065 
3066 		err = bpf_check_attach_target(NULL, prog, tgt_prog, btf_id,
3067 					      &tgt_info);
3068 		if (err)
3069 			goto out_unlock;
3070 
3071 		tr = bpf_trampoline_get(key, &tgt_info);
3072 		if (!tr) {
3073 			err = -ENOMEM;
3074 			goto out_unlock;
3075 		}
3076 	} else {
3077 		/* The caller didn't specify a target, or the target was the
3078 		 * same as the destination supplied during program load. This
3079 		 * means we can reuse the trampoline and reference from program
3080 		 * load time, and there is no need to allocate a new one. This
3081 		 * can only happen once for any program, as the saved values in
3082 		 * prog->aux are cleared below.
3083 		 */
3084 		tr = prog->aux->dst_trampoline;
3085 		tgt_prog = prog->aux->dst_prog;
3086 	}
3087 
3088 	err = bpf_link_prime(&link->link.link, &link_primer);
3089 	if (err)
3090 		goto out_unlock;
3091 
3092 	err = bpf_trampoline_link_prog(&link->link, tr);
3093 	if (err) {
3094 		bpf_link_cleanup(&link_primer);
3095 		link = NULL;
3096 		goto out_unlock;
3097 	}
3098 
3099 	link->tgt_prog = tgt_prog;
3100 	link->trampoline = tr;
3101 
3102 	/* Always clear the trampoline and target prog from prog->aux to make
3103 	 * sure the original attach destination is not kept alive after a
3104 	 * program is (re-)attached to another target.
3105 	 */
3106 	if (prog->aux->dst_prog &&
3107 	    (tgt_prog_fd || tr != prog->aux->dst_trampoline))
3108 		/* got extra prog ref from syscall, or attaching to different prog */
3109 		bpf_prog_put(prog->aux->dst_prog);
3110 	if (prog->aux->dst_trampoline && tr != prog->aux->dst_trampoline)
3111 		/* we allocated a new trampoline, so free the old one */
3112 		bpf_trampoline_put(prog->aux->dst_trampoline);
3113 
3114 	prog->aux->dst_prog = NULL;
3115 	prog->aux->dst_trampoline = NULL;
3116 	mutex_unlock(&prog->aux->dst_mutex);
3117 
3118 	return bpf_link_settle(&link_primer);
3119 out_unlock:
3120 	if (tr && tr != prog->aux->dst_trampoline)
3121 		bpf_trampoline_put(tr);
3122 	mutex_unlock(&prog->aux->dst_mutex);
3123 	kfree(link);
3124 out_put_prog:
3125 	if (tgt_prog_fd && tgt_prog)
3126 		bpf_prog_put(tgt_prog);
3127 	return err;
3128 }
3129 
3130 struct bpf_raw_tp_link {
3131 	struct bpf_link link;
3132 	struct bpf_raw_event_map *btp;
3133 };
3134 
3135 static void bpf_raw_tp_link_release(struct bpf_link *link)
3136 {
3137 	struct bpf_raw_tp_link *raw_tp =
3138 		container_of(link, struct bpf_raw_tp_link, link);
3139 
3140 	bpf_probe_unregister(raw_tp->btp, raw_tp->link.prog);
3141 	bpf_put_raw_tracepoint(raw_tp->btp);
3142 }
3143 
3144 static void bpf_raw_tp_link_dealloc(struct bpf_link *link)
3145 {
3146 	struct bpf_raw_tp_link *raw_tp =
3147 		container_of(link, struct bpf_raw_tp_link, link);
3148 
3149 	kfree(raw_tp);
3150 }
3151 
3152 static void bpf_raw_tp_link_show_fdinfo(const struct bpf_link *link,
3153 					struct seq_file *seq)
3154 {
3155 	struct bpf_raw_tp_link *raw_tp_link =
3156 		container_of(link, struct bpf_raw_tp_link, link);
3157 
3158 	seq_printf(seq,
3159 		   "tp_name:\t%s\n",
3160 		   raw_tp_link->btp->tp->name);
3161 }
3162 
3163 static int bpf_raw_tp_link_fill_link_info(const struct bpf_link *link,
3164 					  struct bpf_link_info *info)
3165 {
3166 	struct bpf_raw_tp_link *raw_tp_link =
3167 		container_of(link, struct bpf_raw_tp_link, link);
3168 	char __user *ubuf = u64_to_user_ptr(info->raw_tracepoint.tp_name);
3169 	const char *tp_name = raw_tp_link->btp->tp->name;
3170 	u32 ulen = info->raw_tracepoint.tp_name_len;
3171 	size_t tp_len = strlen(tp_name);
3172 
3173 	if (!ulen ^ !ubuf)
3174 		return -EINVAL;
3175 
3176 	info->raw_tracepoint.tp_name_len = tp_len + 1;
3177 
3178 	if (!ubuf)
3179 		return 0;
3180 
3181 	if (ulen >= tp_len + 1) {
3182 		if (copy_to_user(ubuf, tp_name, tp_len + 1))
3183 			return -EFAULT;
3184 	} else {
3185 		char zero = '\0';
3186 
3187 		if (copy_to_user(ubuf, tp_name, ulen - 1))
3188 			return -EFAULT;
3189 		if (put_user(zero, ubuf + ulen - 1))
3190 			return -EFAULT;
3191 		return -ENOSPC;
3192 	}
3193 
3194 	return 0;
3195 }
3196 
3197 static const struct bpf_link_ops bpf_raw_tp_link_lops = {
3198 	.release = bpf_raw_tp_link_release,
3199 	.dealloc = bpf_raw_tp_link_dealloc,
3200 	.show_fdinfo = bpf_raw_tp_link_show_fdinfo,
3201 	.fill_link_info = bpf_raw_tp_link_fill_link_info,
3202 };
3203 
3204 #ifdef CONFIG_PERF_EVENTS
3205 struct bpf_perf_link {
3206 	struct bpf_link link;
3207 	struct file *perf_file;
3208 };
3209 
3210 static void bpf_perf_link_release(struct bpf_link *link)
3211 {
3212 	struct bpf_perf_link *perf_link = container_of(link, struct bpf_perf_link, link);
3213 	struct perf_event *event = perf_link->perf_file->private_data;
3214 
3215 	perf_event_free_bpf_prog(event);
3216 	fput(perf_link->perf_file);
3217 }
3218 
3219 static void bpf_perf_link_dealloc(struct bpf_link *link)
3220 {
3221 	struct bpf_perf_link *perf_link = container_of(link, struct bpf_perf_link, link);
3222 
3223 	kfree(perf_link);
3224 }
3225 
3226 static const struct bpf_link_ops bpf_perf_link_lops = {
3227 	.release = bpf_perf_link_release,
3228 	.dealloc = bpf_perf_link_dealloc,
3229 };
3230 
3231 static int bpf_perf_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
3232 {
3233 	struct bpf_link_primer link_primer;
3234 	struct bpf_perf_link *link;
3235 	struct perf_event *event;
3236 	struct file *perf_file;
3237 	int err;
3238 
3239 	if (attr->link_create.flags)
3240 		return -EINVAL;
3241 
3242 	perf_file = perf_event_get(attr->link_create.target_fd);
3243 	if (IS_ERR(perf_file))
3244 		return PTR_ERR(perf_file);
3245 
3246 	link = kzalloc(sizeof(*link), GFP_USER);
3247 	if (!link) {
3248 		err = -ENOMEM;
3249 		goto out_put_file;
3250 	}
3251 	bpf_link_init(&link->link, BPF_LINK_TYPE_PERF_EVENT, &bpf_perf_link_lops, prog);
3252 	link->perf_file = perf_file;
3253 
3254 	err = bpf_link_prime(&link->link, &link_primer);
3255 	if (err) {
3256 		kfree(link);
3257 		goto out_put_file;
3258 	}
3259 
3260 	event = perf_file->private_data;
3261 	err = perf_event_set_bpf_prog(event, prog, attr->link_create.perf_event.bpf_cookie);
3262 	if (err) {
3263 		bpf_link_cleanup(&link_primer);
3264 		goto out_put_file;
3265 	}
3266 	/* perf_event_set_bpf_prog() doesn't take its own refcnt on prog */
3267 	bpf_prog_inc(prog);
3268 
3269 	return bpf_link_settle(&link_primer);
3270 
3271 out_put_file:
3272 	fput(perf_file);
3273 	return err;
3274 }
3275 #else
3276 static int bpf_perf_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
3277 {
3278 	return -EOPNOTSUPP;
3279 }
3280 #endif /* CONFIG_PERF_EVENTS */
3281 
3282 static int bpf_raw_tp_link_attach(struct bpf_prog *prog,
3283 				  const char __user *user_tp_name)
3284 {
3285 	struct bpf_link_primer link_primer;
3286 	struct bpf_raw_tp_link *link;
3287 	struct bpf_raw_event_map *btp;
3288 	const char *tp_name;
3289 	char buf[128];
3290 	int err;
3291 
3292 	switch (prog->type) {
3293 	case BPF_PROG_TYPE_TRACING:
3294 	case BPF_PROG_TYPE_EXT:
3295 	case BPF_PROG_TYPE_LSM:
3296 		if (user_tp_name)
3297 			/* The attach point for this category of programs
3298 			 * should be specified via btf_id during program load.
3299 			 */
3300 			return -EINVAL;
3301 		if (prog->type == BPF_PROG_TYPE_TRACING &&
3302 		    prog->expected_attach_type == BPF_TRACE_RAW_TP) {
3303 			tp_name = prog->aux->attach_func_name;
3304 			break;
3305 		}
3306 		return bpf_tracing_prog_attach(prog, 0, 0, 0);
3307 	case BPF_PROG_TYPE_RAW_TRACEPOINT:
3308 	case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE:
3309 		if (strncpy_from_user(buf, user_tp_name, sizeof(buf) - 1) < 0)
3310 			return -EFAULT;
3311 		buf[sizeof(buf) - 1] = 0;
3312 		tp_name = buf;
3313 		break;
3314 	default:
3315 		return -EINVAL;
3316 	}
3317 
3318 	btp = bpf_get_raw_tracepoint(tp_name);
3319 	if (!btp)
3320 		return -ENOENT;
3321 
3322 	link = kzalloc(sizeof(*link), GFP_USER);
3323 	if (!link) {
3324 		err = -ENOMEM;
3325 		goto out_put_btp;
3326 	}
3327 	bpf_link_init(&link->link, BPF_LINK_TYPE_RAW_TRACEPOINT,
3328 		      &bpf_raw_tp_link_lops, prog);
3329 	link->btp = btp;
3330 
3331 	err = bpf_link_prime(&link->link, &link_primer);
3332 	if (err) {
3333 		kfree(link);
3334 		goto out_put_btp;
3335 	}
3336 
3337 	err = bpf_probe_register(link->btp, prog);
3338 	if (err) {
3339 		bpf_link_cleanup(&link_primer);
3340 		goto out_put_btp;
3341 	}
3342 
3343 	return bpf_link_settle(&link_primer);
3344 
3345 out_put_btp:
3346 	bpf_put_raw_tracepoint(btp);
3347 	return err;
3348 }
3349 
3350 #define BPF_RAW_TRACEPOINT_OPEN_LAST_FIELD raw_tracepoint.prog_fd
3351 
3352 static int bpf_raw_tracepoint_open(const union bpf_attr *attr)
3353 {
3354 	struct bpf_prog *prog;
3355 	int fd;
3356 
3357 	if (CHECK_ATTR(BPF_RAW_TRACEPOINT_OPEN))
3358 		return -EINVAL;
3359 
3360 	prog = bpf_prog_get(attr->raw_tracepoint.prog_fd);
3361 	if (IS_ERR(prog))
3362 		return PTR_ERR(prog);
3363 
3364 	fd = bpf_raw_tp_link_attach(prog, u64_to_user_ptr(attr->raw_tracepoint.name));
3365 	if (fd < 0)
3366 		bpf_prog_put(prog);
3367 	return fd;
3368 }
3369 
3370 static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog,
3371 					     enum bpf_attach_type attach_type)
3372 {
3373 	switch (prog->type) {
3374 	case BPF_PROG_TYPE_CGROUP_SOCK:
3375 	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
3376 	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
3377 	case BPF_PROG_TYPE_SK_LOOKUP:
3378 		return attach_type == prog->expected_attach_type ? 0 : -EINVAL;
3379 	case BPF_PROG_TYPE_CGROUP_SKB:
3380 		if (!capable(CAP_NET_ADMIN))
3381 			/* cg-skb progs can be loaded by unpriv user.
3382 			 * check permissions at attach time.
3383 			 */
3384 			return -EPERM;
3385 		return prog->enforce_expected_attach_type &&
3386 			prog->expected_attach_type != attach_type ?
3387 			-EINVAL : 0;
3388 	default:
3389 		return 0;
3390 	}
3391 }
3392 
3393 static enum bpf_prog_type
3394 attach_type_to_prog_type(enum bpf_attach_type attach_type)
3395 {
3396 	switch (attach_type) {
3397 	case BPF_CGROUP_INET_INGRESS:
3398 	case BPF_CGROUP_INET_EGRESS:
3399 		return BPF_PROG_TYPE_CGROUP_SKB;
3400 	case BPF_CGROUP_INET_SOCK_CREATE:
3401 	case BPF_CGROUP_INET_SOCK_RELEASE:
3402 	case BPF_CGROUP_INET4_POST_BIND:
3403 	case BPF_CGROUP_INET6_POST_BIND:
3404 		return BPF_PROG_TYPE_CGROUP_SOCK;
3405 	case BPF_CGROUP_INET4_BIND:
3406 	case BPF_CGROUP_INET6_BIND:
3407 	case BPF_CGROUP_INET4_CONNECT:
3408 	case BPF_CGROUP_INET6_CONNECT:
3409 	case BPF_CGROUP_INET4_GETPEERNAME:
3410 	case BPF_CGROUP_INET6_GETPEERNAME:
3411 	case BPF_CGROUP_INET4_GETSOCKNAME:
3412 	case BPF_CGROUP_INET6_GETSOCKNAME:
3413 	case BPF_CGROUP_UDP4_SENDMSG:
3414 	case BPF_CGROUP_UDP6_SENDMSG:
3415 	case BPF_CGROUP_UDP4_RECVMSG:
3416 	case BPF_CGROUP_UDP6_RECVMSG:
3417 		return BPF_PROG_TYPE_CGROUP_SOCK_ADDR;
3418 	case BPF_CGROUP_SOCK_OPS:
3419 		return BPF_PROG_TYPE_SOCK_OPS;
3420 	case BPF_CGROUP_DEVICE:
3421 		return BPF_PROG_TYPE_CGROUP_DEVICE;
3422 	case BPF_SK_MSG_VERDICT:
3423 		return BPF_PROG_TYPE_SK_MSG;
3424 	case BPF_SK_SKB_STREAM_PARSER:
3425 	case BPF_SK_SKB_STREAM_VERDICT:
3426 	case BPF_SK_SKB_VERDICT:
3427 		return BPF_PROG_TYPE_SK_SKB;
3428 	case BPF_LIRC_MODE2:
3429 		return BPF_PROG_TYPE_LIRC_MODE2;
3430 	case BPF_FLOW_DISSECTOR:
3431 		return BPF_PROG_TYPE_FLOW_DISSECTOR;
3432 	case BPF_CGROUP_SYSCTL:
3433 		return BPF_PROG_TYPE_CGROUP_SYSCTL;
3434 	case BPF_CGROUP_GETSOCKOPT:
3435 	case BPF_CGROUP_SETSOCKOPT:
3436 		return BPF_PROG_TYPE_CGROUP_SOCKOPT;
3437 	case BPF_TRACE_ITER:
3438 	case BPF_TRACE_RAW_TP:
3439 	case BPF_TRACE_FENTRY:
3440 	case BPF_TRACE_FEXIT:
3441 	case BPF_MODIFY_RETURN:
3442 		return BPF_PROG_TYPE_TRACING;
3443 	case BPF_LSM_MAC:
3444 		return BPF_PROG_TYPE_LSM;
3445 	case BPF_SK_LOOKUP:
3446 		return BPF_PROG_TYPE_SK_LOOKUP;
3447 	case BPF_XDP:
3448 		return BPF_PROG_TYPE_XDP;
3449 	case BPF_LSM_CGROUP:
3450 		return BPF_PROG_TYPE_LSM;
3451 	default:
3452 		return BPF_PROG_TYPE_UNSPEC;
3453 	}
3454 }
3455 
3456 #define BPF_PROG_ATTACH_LAST_FIELD replace_bpf_fd
3457 
3458 #define BPF_F_ATTACH_MASK \
3459 	(BPF_F_ALLOW_OVERRIDE | BPF_F_ALLOW_MULTI | BPF_F_REPLACE)
3460 
3461 static int bpf_prog_attach(const union bpf_attr *attr)
3462 {
3463 	enum bpf_prog_type ptype;
3464 	struct bpf_prog *prog;
3465 	int ret;
3466 
3467 	if (CHECK_ATTR(BPF_PROG_ATTACH))
3468 		return -EINVAL;
3469 
3470 	if (attr->attach_flags & ~BPF_F_ATTACH_MASK)
3471 		return -EINVAL;
3472 
3473 	ptype = attach_type_to_prog_type(attr->attach_type);
3474 	if (ptype == BPF_PROG_TYPE_UNSPEC)
3475 		return -EINVAL;
3476 
3477 	prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype);
3478 	if (IS_ERR(prog))
3479 		return PTR_ERR(prog);
3480 
3481 	if (bpf_prog_attach_check_attach_type(prog, attr->attach_type)) {
3482 		bpf_prog_put(prog);
3483 		return -EINVAL;
3484 	}
3485 
3486 	switch (ptype) {
3487 	case BPF_PROG_TYPE_SK_SKB:
3488 	case BPF_PROG_TYPE_SK_MSG:
3489 		ret = sock_map_get_from_fd(attr, prog);
3490 		break;
3491 	case BPF_PROG_TYPE_LIRC_MODE2:
3492 		ret = lirc_prog_attach(attr, prog);
3493 		break;
3494 	case BPF_PROG_TYPE_FLOW_DISSECTOR:
3495 		ret = netns_bpf_prog_attach(attr, prog);
3496 		break;
3497 	case BPF_PROG_TYPE_CGROUP_DEVICE:
3498 	case BPF_PROG_TYPE_CGROUP_SKB:
3499 	case BPF_PROG_TYPE_CGROUP_SOCK:
3500 	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
3501 	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
3502 	case BPF_PROG_TYPE_CGROUP_SYSCTL:
3503 	case BPF_PROG_TYPE_SOCK_OPS:
3504 	case BPF_PROG_TYPE_LSM:
3505 		if (ptype == BPF_PROG_TYPE_LSM &&
3506 		    prog->expected_attach_type != BPF_LSM_CGROUP)
3507 			return -EINVAL;
3508 
3509 		ret = cgroup_bpf_prog_attach(attr, ptype, prog);
3510 		break;
3511 	default:
3512 		ret = -EINVAL;
3513 	}
3514 
3515 	if (ret)
3516 		bpf_prog_put(prog);
3517 	return ret;
3518 }
3519 
3520 #define BPF_PROG_DETACH_LAST_FIELD attach_type
3521 
3522 static int bpf_prog_detach(const union bpf_attr *attr)
3523 {
3524 	enum bpf_prog_type ptype;
3525 
3526 	if (CHECK_ATTR(BPF_PROG_DETACH))
3527 		return -EINVAL;
3528 
3529 	ptype = attach_type_to_prog_type(attr->attach_type);
3530 
3531 	switch (ptype) {
3532 	case BPF_PROG_TYPE_SK_MSG:
3533 	case BPF_PROG_TYPE_SK_SKB:
3534 		return sock_map_prog_detach(attr, ptype);
3535 	case BPF_PROG_TYPE_LIRC_MODE2:
3536 		return lirc_prog_detach(attr);
3537 	case BPF_PROG_TYPE_FLOW_DISSECTOR:
3538 		return netns_bpf_prog_detach(attr, ptype);
3539 	case BPF_PROG_TYPE_CGROUP_DEVICE:
3540 	case BPF_PROG_TYPE_CGROUP_SKB:
3541 	case BPF_PROG_TYPE_CGROUP_SOCK:
3542 	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
3543 	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
3544 	case BPF_PROG_TYPE_CGROUP_SYSCTL:
3545 	case BPF_PROG_TYPE_SOCK_OPS:
3546 	case BPF_PROG_TYPE_LSM:
3547 		return cgroup_bpf_prog_detach(attr, ptype);
3548 	default:
3549 		return -EINVAL;
3550 	}
3551 }
3552 
3553 #define BPF_PROG_QUERY_LAST_FIELD query.prog_attach_flags
3554 
3555 static int bpf_prog_query(const union bpf_attr *attr,
3556 			  union bpf_attr __user *uattr)
3557 {
3558 	if (!capable(CAP_NET_ADMIN))
3559 		return -EPERM;
3560 	if (CHECK_ATTR(BPF_PROG_QUERY))
3561 		return -EINVAL;
3562 	if (attr->query.query_flags & ~BPF_F_QUERY_EFFECTIVE)
3563 		return -EINVAL;
3564 
3565 	switch (attr->query.attach_type) {
3566 	case BPF_CGROUP_INET_INGRESS:
3567 	case BPF_CGROUP_INET_EGRESS:
3568 	case BPF_CGROUP_INET_SOCK_CREATE:
3569 	case BPF_CGROUP_INET_SOCK_RELEASE:
3570 	case BPF_CGROUP_INET4_BIND:
3571 	case BPF_CGROUP_INET6_BIND:
3572 	case BPF_CGROUP_INET4_POST_BIND:
3573 	case BPF_CGROUP_INET6_POST_BIND:
3574 	case BPF_CGROUP_INET4_CONNECT:
3575 	case BPF_CGROUP_INET6_CONNECT:
3576 	case BPF_CGROUP_INET4_GETPEERNAME:
3577 	case BPF_CGROUP_INET6_GETPEERNAME:
3578 	case BPF_CGROUP_INET4_GETSOCKNAME:
3579 	case BPF_CGROUP_INET6_GETSOCKNAME:
3580 	case BPF_CGROUP_UDP4_SENDMSG:
3581 	case BPF_CGROUP_UDP6_SENDMSG:
3582 	case BPF_CGROUP_UDP4_RECVMSG:
3583 	case BPF_CGROUP_UDP6_RECVMSG:
3584 	case BPF_CGROUP_SOCK_OPS:
3585 	case BPF_CGROUP_DEVICE:
3586 	case BPF_CGROUP_SYSCTL:
3587 	case BPF_CGROUP_GETSOCKOPT:
3588 	case BPF_CGROUP_SETSOCKOPT:
3589 	case BPF_LSM_CGROUP:
3590 		return cgroup_bpf_prog_query(attr, uattr);
3591 	case BPF_LIRC_MODE2:
3592 		return lirc_prog_query(attr, uattr);
3593 	case BPF_FLOW_DISSECTOR:
3594 	case BPF_SK_LOOKUP:
3595 		return netns_bpf_prog_query(attr, uattr);
3596 	case BPF_SK_SKB_STREAM_PARSER:
3597 	case BPF_SK_SKB_STREAM_VERDICT:
3598 	case BPF_SK_MSG_VERDICT:
3599 	case BPF_SK_SKB_VERDICT:
3600 		return sock_map_bpf_prog_query(attr, uattr);
3601 	default:
3602 		return -EINVAL;
3603 	}
3604 }
3605 
3606 #define BPF_PROG_TEST_RUN_LAST_FIELD test.batch_size
3607 
3608 static int bpf_prog_test_run(const union bpf_attr *attr,
3609 			     union bpf_attr __user *uattr)
3610 {
3611 	struct bpf_prog *prog;
3612 	int ret = -ENOTSUPP;
3613 
3614 	if (CHECK_ATTR(BPF_PROG_TEST_RUN))
3615 		return -EINVAL;
3616 
3617 	if ((attr->test.ctx_size_in && !attr->test.ctx_in) ||
3618 	    (!attr->test.ctx_size_in && attr->test.ctx_in))
3619 		return -EINVAL;
3620 
3621 	if ((attr->test.ctx_size_out && !attr->test.ctx_out) ||
3622 	    (!attr->test.ctx_size_out && attr->test.ctx_out))
3623 		return -EINVAL;
3624 
3625 	prog = bpf_prog_get(attr->test.prog_fd);
3626 	if (IS_ERR(prog))
3627 		return PTR_ERR(prog);
3628 
3629 	if (prog->aux->ops->test_run)
3630 		ret = prog->aux->ops->test_run(prog, attr, uattr);
3631 
3632 	bpf_prog_put(prog);
3633 	return ret;
3634 }
3635 
3636 #define BPF_OBJ_GET_NEXT_ID_LAST_FIELD next_id
3637 
3638 static int bpf_obj_get_next_id(const union bpf_attr *attr,
3639 			       union bpf_attr __user *uattr,
3640 			       struct idr *idr,
3641 			       spinlock_t *lock)
3642 {
3643 	u32 next_id = attr->start_id;
3644 	int err = 0;
3645 
3646 	if (CHECK_ATTR(BPF_OBJ_GET_NEXT_ID) || next_id >= INT_MAX)
3647 		return -EINVAL;
3648 
3649 	if (!capable(CAP_SYS_ADMIN))
3650 		return -EPERM;
3651 
3652 	next_id++;
3653 	spin_lock_bh(lock);
3654 	if (!idr_get_next(idr, &next_id))
3655 		err = -ENOENT;
3656 	spin_unlock_bh(lock);
3657 
3658 	if (!err)
3659 		err = put_user(next_id, &uattr->next_id);
3660 
3661 	return err;
3662 }
3663 
3664 struct bpf_map *bpf_map_get_curr_or_next(u32 *id)
3665 {
3666 	struct bpf_map *map;
3667 
3668 	spin_lock_bh(&map_idr_lock);
3669 again:
3670 	map = idr_get_next(&map_idr, id);
3671 	if (map) {
3672 		map = __bpf_map_inc_not_zero(map, false);
3673 		if (IS_ERR(map)) {
3674 			(*id)++;
3675 			goto again;
3676 		}
3677 	}
3678 	spin_unlock_bh(&map_idr_lock);
3679 
3680 	return map;
3681 }
3682 
3683 struct bpf_prog *bpf_prog_get_curr_or_next(u32 *id)
3684 {
3685 	struct bpf_prog *prog;
3686 
3687 	spin_lock_bh(&prog_idr_lock);
3688 again:
3689 	prog = idr_get_next(&prog_idr, id);
3690 	if (prog) {
3691 		prog = bpf_prog_inc_not_zero(prog);
3692 		if (IS_ERR(prog)) {
3693 			(*id)++;
3694 			goto again;
3695 		}
3696 	}
3697 	spin_unlock_bh(&prog_idr_lock);
3698 
3699 	return prog;
3700 }
3701 
3702 #define BPF_PROG_GET_FD_BY_ID_LAST_FIELD prog_id
3703 
3704 struct bpf_prog *bpf_prog_by_id(u32 id)
3705 {
3706 	struct bpf_prog *prog;
3707 
3708 	if (!id)
3709 		return ERR_PTR(-ENOENT);
3710 
3711 	spin_lock_bh(&prog_idr_lock);
3712 	prog = idr_find(&prog_idr, id);
3713 	if (prog)
3714 		prog = bpf_prog_inc_not_zero(prog);
3715 	else
3716 		prog = ERR_PTR(-ENOENT);
3717 	spin_unlock_bh(&prog_idr_lock);
3718 	return prog;
3719 }
3720 
3721 static int bpf_prog_get_fd_by_id(const union bpf_attr *attr)
3722 {
3723 	struct bpf_prog *prog;
3724 	u32 id = attr->prog_id;
3725 	int fd;
3726 
3727 	if (CHECK_ATTR(BPF_PROG_GET_FD_BY_ID))
3728 		return -EINVAL;
3729 
3730 	if (!capable(CAP_SYS_ADMIN))
3731 		return -EPERM;
3732 
3733 	prog = bpf_prog_by_id(id);
3734 	if (IS_ERR(prog))
3735 		return PTR_ERR(prog);
3736 
3737 	fd = bpf_prog_new_fd(prog);
3738 	if (fd < 0)
3739 		bpf_prog_put(prog);
3740 
3741 	return fd;
3742 }
3743 
3744 #define BPF_MAP_GET_FD_BY_ID_LAST_FIELD open_flags
3745 
3746 static int bpf_map_get_fd_by_id(const union bpf_attr *attr)
3747 {
3748 	struct bpf_map *map;
3749 	u32 id = attr->map_id;
3750 	int f_flags;
3751 	int fd;
3752 
3753 	if (CHECK_ATTR(BPF_MAP_GET_FD_BY_ID) ||
3754 	    attr->open_flags & ~BPF_OBJ_FLAG_MASK)
3755 		return -EINVAL;
3756 
3757 	if (!capable(CAP_SYS_ADMIN))
3758 		return -EPERM;
3759 
3760 	f_flags = bpf_get_file_flag(attr->open_flags);
3761 	if (f_flags < 0)
3762 		return f_flags;
3763 
3764 	spin_lock_bh(&map_idr_lock);
3765 	map = idr_find(&map_idr, id);
3766 	if (map)
3767 		map = __bpf_map_inc_not_zero(map, true);
3768 	else
3769 		map = ERR_PTR(-ENOENT);
3770 	spin_unlock_bh(&map_idr_lock);
3771 
3772 	if (IS_ERR(map))
3773 		return PTR_ERR(map);
3774 
3775 	fd = bpf_map_new_fd(map, f_flags);
3776 	if (fd < 0)
3777 		bpf_map_put_with_uref(map);
3778 
3779 	return fd;
3780 }
3781 
3782 static const struct bpf_map *bpf_map_from_imm(const struct bpf_prog *prog,
3783 					      unsigned long addr, u32 *off,
3784 					      u32 *type)
3785 {
3786 	const struct bpf_map *map;
3787 	int i;
3788 
3789 	mutex_lock(&prog->aux->used_maps_mutex);
3790 	for (i = 0, *off = 0; i < prog->aux->used_map_cnt; i++) {
3791 		map = prog->aux->used_maps[i];
3792 		if (map == (void *)addr) {
3793 			*type = BPF_PSEUDO_MAP_FD;
3794 			goto out;
3795 		}
3796 		if (!map->ops->map_direct_value_meta)
3797 			continue;
3798 		if (!map->ops->map_direct_value_meta(map, addr, off)) {
3799 			*type = BPF_PSEUDO_MAP_VALUE;
3800 			goto out;
3801 		}
3802 	}
3803 	map = NULL;
3804 
3805 out:
3806 	mutex_unlock(&prog->aux->used_maps_mutex);
3807 	return map;
3808 }
3809 
3810 static struct bpf_insn *bpf_insn_prepare_dump(const struct bpf_prog *prog,
3811 					      const struct cred *f_cred)
3812 {
3813 	const struct bpf_map *map;
3814 	struct bpf_insn *insns;
3815 	u32 off, type;
3816 	u64 imm;
3817 	u8 code;
3818 	int i;
3819 
3820 	insns = kmemdup(prog->insnsi, bpf_prog_insn_size(prog),
3821 			GFP_USER);
3822 	if (!insns)
3823 		return insns;
3824 
3825 	for (i = 0; i < prog->len; i++) {
3826 		code = insns[i].code;
3827 
3828 		if (code == (BPF_JMP | BPF_TAIL_CALL)) {
3829 			insns[i].code = BPF_JMP | BPF_CALL;
3830 			insns[i].imm = BPF_FUNC_tail_call;
3831 			/* fall-through */
3832 		}
3833 		if (code == (BPF_JMP | BPF_CALL) ||
3834 		    code == (BPF_JMP | BPF_CALL_ARGS)) {
3835 			if (code == (BPF_JMP | BPF_CALL_ARGS))
3836 				insns[i].code = BPF_JMP | BPF_CALL;
3837 			if (!bpf_dump_raw_ok(f_cred))
3838 				insns[i].imm = 0;
3839 			continue;
3840 		}
3841 		if (BPF_CLASS(code) == BPF_LDX && BPF_MODE(code) == BPF_PROBE_MEM) {
3842 			insns[i].code = BPF_LDX | BPF_SIZE(code) | BPF_MEM;
3843 			continue;
3844 		}
3845 
3846 		if (code != (BPF_LD | BPF_IMM | BPF_DW))
3847 			continue;
3848 
3849 		imm = ((u64)insns[i + 1].imm << 32) | (u32)insns[i].imm;
3850 		map = bpf_map_from_imm(prog, imm, &off, &type);
3851 		if (map) {
3852 			insns[i].src_reg = type;
3853 			insns[i].imm = map->id;
3854 			insns[i + 1].imm = off;
3855 			continue;
3856 		}
3857 	}
3858 
3859 	return insns;
3860 }
3861 
3862 static int set_info_rec_size(struct bpf_prog_info *info)
3863 {
3864 	/*
3865 	 * Ensure info.*_rec_size is the same as kernel expected size
3866 	 *
3867 	 * or
3868 	 *
3869 	 * Only allow zero *_rec_size if both _rec_size and _cnt are
3870 	 * zero.  In this case, the kernel will set the expected
3871 	 * _rec_size back to the info.
3872 	 */
3873 
3874 	if ((info->nr_func_info || info->func_info_rec_size) &&
3875 	    info->func_info_rec_size != sizeof(struct bpf_func_info))
3876 		return -EINVAL;
3877 
3878 	if ((info->nr_line_info || info->line_info_rec_size) &&
3879 	    info->line_info_rec_size != sizeof(struct bpf_line_info))
3880 		return -EINVAL;
3881 
3882 	if ((info->nr_jited_line_info || info->jited_line_info_rec_size) &&
3883 	    info->jited_line_info_rec_size != sizeof(__u64))
3884 		return -EINVAL;
3885 
3886 	info->func_info_rec_size = sizeof(struct bpf_func_info);
3887 	info->line_info_rec_size = sizeof(struct bpf_line_info);
3888 	info->jited_line_info_rec_size = sizeof(__u64);
3889 
3890 	return 0;
3891 }
3892 
3893 static int bpf_prog_get_info_by_fd(struct file *file,
3894 				   struct bpf_prog *prog,
3895 				   const union bpf_attr *attr,
3896 				   union bpf_attr __user *uattr)
3897 {
3898 	struct bpf_prog_info __user *uinfo = u64_to_user_ptr(attr->info.info);
3899 	struct btf *attach_btf = bpf_prog_get_target_btf(prog);
3900 	struct bpf_prog_info info;
3901 	u32 info_len = attr->info.info_len;
3902 	struct bpf_prog_kstats stats;
3903 	char __user *uinsns;
3904 	u32 ulen;
3905 	int err;
3906 
3907 	err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len);
3908 	if (err)
3909 		return err;
3910 	info_len = min_t(u32, sizeof(info), info_len);
3911 
3912 	memset(&info, 0, sizeof(info));
3913 	if (copy_from_user(&info, uinfo, info_len))
3914 		return -EFAULT;
3915 
3916 	info.type = prog->type;
3917 	info.id = prog->aux->id;
3918 	info.load_time = prog->aux->load_time;
3919 	info.created_by_uid = from_kuid_munged(current_user_ns(),
3920 					       prog->aux->user->uid);
3921 	info.gpl_compatible = prog->gpl_compatible;
3922 
3923 	memcpy(info.tag, prog->tag, sizeof(prog->tag));
3924 	memcpy(info.name, prog->aux->name, sizeof(prog->aux->name));
3925 
3926 	mutex_lock(&prog->aux->used_maps_mutex);
3927 	ulen = info.nr_map_ids;
3928 	info.nr_map_ids = prog->aux->used_map_cnt;
3929 	ulen = min_t(u32, info.nr_map_ids, ulen);
3930 	if (ulen) {
3931 		u32 __user *user_map_ids = u64_to_user_ptr(info.map_ids);
3932 		u32 i;
3933 
3934 		for (i = 0; i < ulen; i++)
3935 			if (put_user(prog->aux->used_maps[i]->id,
3936 				     &user_map_ids[i])) {
3937 				mutex_unlock(&prog->aux->used_maps_mutex);
3938 				return -EFAULT;
3939 			}
3940 	}
3941 	mutex_unlock(&prog->aux->used_maps_mutex);
3942 
3943 	err = set_info_rec_size(&info);
3944 	if (err)
3945 		return err;
3946 
3947 	bpf_prog_get_stats(prog, &stats);
3948 	info.run_time_ns = stats.nsecs;
3949 	info.run_cnt = stats.cnt;
3950 	info.recursion_misses = stats.misses;
3951 
3952 	info.verified_insns = prog->aux->verified_insns;
3953 
3954 	if (!bpf_capable()) {
3955 		info.jited_prog_len = 0;
3956 		info.xlated_prog_len = 0;
3957 		info.nr_jited_ksyms = 0;
3958 		info.nr_jited_func_lens = 0;
3959 		info.nr_func_info = 0;
3960 		info.nr_line_info = 0;
3961 		info.nr_jited_line_info = 0;
3962 		goto done;
3963 	}
3964 
3965 	ulen = info.xlated_prog_len;
3966 	info.xlated_prog_len = bpf_prog_insn_size(prog);
3967 	if (info.xlated_prog_len && ulen) {
3968 		struct bpf_insn *insns_sanitized;
3969 		bool fault;
3970 
3971 		if (prog->blinded && !bpf_dump_raw_ok(file->f_cred)) {
3972 			info.xlated_prog_insns = 0;
3973 			goto done;
3974 		}
3975 		insns_sanitized = bpf_insn_prepare_dump(prog, file->f_cred);
3976 		if (!insns_sanitized)
3977 			return -ENOMEM;
3978 		uinsns = u64_to_user_ptr(info.xlated_prog_insns);
3979 		ulen = min_t(u32, info.xlated_prog_len, ulen);
3980 		fault = copy_to_user(uinsns, insns_sanitized, ulen);
3981 		kfree(insns_sanitized);
3982 		if (fault)
3983 			return -EFAULT;
3984 	}
3985 
3986 	if (bpf_prog_is_dev_bound(prog->aux)) {
3987 		err = bpf_prog_offload_info_fill(&info, prog);
3988 		if (err)
3989 			return err;
3990 		goto done;
3991 	}
3992 
3993 	/* NOTE: the following code is supposed to be skipped for offload.
3994 	 * bpf_prog_offload_info_fill() is the place to fill similar fields
3995 	 * for offload.
3996 	 */
3997 	ulen = info.jited_prog_len;
3998 	if (prog->aux->func_cnt) {
3999 		u32 i;
4000 
4001 		info.jited_prog_len = 0;
4002 		for (i = 0; i < prog->aux->func_cnt; i++)
4003 			info.jited_prog_len += prog->aux->func[i]->jited_len;
4004 	} else {
4005 		info.jited_prog_len = prog->jited_len;
4006 	}
4007 
4008 	if (info.jited_prog_len && ulen) {
4009 		if (bpf_dump_raw_ok(file->f_cred)) {
4010 			uinsns = u64_to_user_ptr(info.jited_prog_insns);
4011 			ulen = min_t(u32, info.jited_prog_len, ulen);
4012 
4013 			/* for multi-function programs, copy the JITed
4014 			 * instructions for all the functions
4015 			 */
4016 			if (prog->aux->func_cnt) {
4017 				u32 len, free, i;
4018 				u8 *img;
4019 
4020 				free = ulen;
4021 				for (i = 0; i < prog->aux->func_cnt; i++) {
4022 					len = prog->aux->func[i]->jited_len;
4023 					len = min_t(u32, len, free);
4024 					img = (u8 *) prog->aux->func[i]->bpf_func;
4025 					if (copy_to_user(uinsns, img, len))
4026 						return -EFAULT;
4027 					uinsns += len;
4028 					free -= len;
4029 					if (!free)
4030 						break;
4031 				}
4032 			} else {
4033 				if (copy_to_user(uinsns, prog->bpf_func, ulen))
4034 					return -EFAULT;
4035 			}
4036 		} else {
4037 			info.jited_prog_insns = 0;
4038 		}
4039 	}
4040 
4041 	ulen = info.nr_jited_ksyms;
4042 	info.nr_jited_ksyms = prog->aux->func_cnt ? : 1;
4043 	if (ulen) {
4044 		if (bpf_dump_raw_ok(file->f_cred)) {
4045 			unsigned long ksym_addr;
4046 			u64 __user *user_ksyms;
4047 			u32 i;
4048 
4049 			/* copy the address of the kernel symbol
4050 			 * corresponding to each function
4051 			 */
4052 			ulen = min_t(u32, info.nr_jited_ksyms, ulen);
4053 			user_ksyms = u64_to_user_ptr(info.jited_ksyms);
4054 			if (prog->aux->func_cnt) {
4055 				for (i = 0; i < ulen; i++) {
4056 					ksym_addr = (unsigned long)
4057 						prog->aux->func[i]->bpf_func;
4058 					if (put_user((u64) ksym_addr,
4059 						     &user_ksyms[i]))
4060 						return -EFAULT;
4061 				}
4062 			} else {
4063 				ksym_addr = (unsigned long) prog->bpf_func;
4064 				if (put_user((u64) ksym_addr, &user_ksyms[0]))
4065 					return -EFAULT;
4066 			}
4067 		} else {
4068 			info.jited_ksyms = 0;
4069 		}
4070 	}
4071 
4072 	ulen = info.nr_jited_func_lens;
4073 	info.nr_jited_func_lens = prog->aux->func_cnt ? : 1;
4074 	if (ulen) {
4075 		if (bpf_dump_raw_ok(file->f_cred)) {
4076 			u32 __user *user_lens;
4077 			u32 func_len, i;
4078 
4079 			/* copy the JITed image lengths for each function */
4080 			ulen = min_t(u32, info.nr_jited_func_lens, ulen);
4081 			user_lens = u64_to_user_ptr(info.jited_func_lens);
4082 			if (prog->aux->func_cnt) {
4083 				for (i = 0; i < ulen; i++) {
4084 					func_len =
4085 						prog->aux->func[i]->jited_len;
4086 					if (put_user(func_len, &user_lens[i]))
4087 						return -EFAULT;
4088 				}
4089 			} else {
4090 				func_len = prog->jited_len;
4091 				if (put_user(func_len, &user_lens[0]))
4092 					return -EFAULT;
4093 			}
4094 		} else {
4095 			info.jited_func_lens = 0;
4096 		}
4097 	}
4098 
4099 	if (prog->aux->btf)
4100 		info.btf_id = btf_obj_id(prog->aux->btf);
4101 	info.attach_btf_id = prog->aux->attach_btf_id;
4102 	if (attach_btf)
4103 		info.attach_btf_obj_id = btf_obj_id(attach_btf);
4104 
4105 	ulen = info.nr_func_info;
4106 	info.nr_func_info = prog->aux->func_info_cnt;
4107 	if (info.nr_func_info && ulen) {
4108 		char __user *user_finfo;
4109 
4110 		user_finfo = u64_to_user_ptr(info.func_info);
4111 		ulen = min_t(u32, info.nr_func_info, ulen);
4112 		if (copy_to_user(user_finfo, prog->aux->func_info,
4113 				 info.func_info_rec_size * ulen))
4114 			return -EFAULT;
4115 	}
4116 
4117 	ulen = info.nr_line_info;
4118 	info.nr_line_info = prog->aux->nr_linfo;
4119 	if (info.nr_line_info && ulen) {
4120 		__u8 __user *user_linfo;
4121 
4122 		user_linfo = u64_to_user_ptr(info.line_info);
4123 		ulen = min_t(u32, info.nr_line_info, ulen);
4124 		if (copy_to_user(user_linfo, prog->aux->linfo,
4125 				 info.line_info_rec_size * ulen))
4126 			return -EFAULT;
4127 	}
4128 
4129 	ulen = info.nr_jited_line_info;
4130 	if (prog->aux->jited_linfo)
4131 		info.nr_jited_line_info = prog->aux->nr_linfo;
4132 	else
4133 		info.nr_jited_line_info = 0;
4134 	if (info.nr_jited_line_info && ulen) {
4135 		if (bpf_dump_raw_ok(file->f_cred)) {
4136 			unsigned long line_addr;
4137 			__u64 __user *user_linfo;
4138 			u32 i;
4139 
4140 			user_linfo = u64_to_user_ptr(info.jited_line_info);
4141 			ulen = min_t(u32, info.nr_jited_line_info, ulen);
4142 			for (i = 0; i < ulen; i++) {
4143 				line_addr = (unsigned long)prog->aux->jited_linfo[i];
4144 				if (put_user((__u64)line_addr, &user_linfo[i]))
4145 					return -EFAULT;
4146 			}
4147 		} else {
4148 			info.jited_line_info = 0;
4149 		}
4150 	}
4151 
4152 	ulen = info.nr_prog_tags;
4153 	info.nr_prog_tags = prog->aux->func_cnt ? : 1;
4154 	if (ulen) {
4155 		__u8 __user (*user_prog_tags)[BPF_TAG_SIZE];
4156 		u32 i;
4157 
4158 		user_prog_tags = u64_to_user_ptr(info.prog_tags);
4159 		ulen = min_t(u32, info.nr_prog_tags, ulen);
4160 		if (prog->aux->func_cnt) {
4161 			for (i = 0; i < ulen; i++) {
4162 				if (copy_to_user(user_prog_tags[i],
4163 						 prog->aux->func[i]->tag,
4164 						 BPF_TAG_SIZE))
4165 					return -EFAULT;
4166 			}
4167 		} else {
4168 			if (copy_to_user(user_prog_tags[0],
4169 					 prog->tag, BPF_TAG_SIZE))
4170 				return -EFAULT;
4171 		}
4172 	}
4173 
4174 done:
4175 	if (copy_to_user(uinfo, &info, info_len) ||
4176 	    put_user(info_len, &uattr->info.info_len))
4177 		return -EFAULT;
4178 
4179 	return 0;
4180 }
4181 
4182 static int bpf_map_get_info_by_fd(struct file *file,
4183 				  struct bpf_map *map,
4184 				  const union bpf_attr *attr,
4185 				  union bpf_attr __user *uattr)
4186 {
4187 	struct bpf_map_info __user *uinfo = u64_to_user_ptr(attr->info.info);
4188 	struct bpf_map_info info;
4189 	u32 info_len = attr->info.info_len;
4190 	int err;
4191 
4192 	err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len);
4193 	if (err)
4194 		return err;
4195 	info_len = min_t(u32, sizeof(info), info_len);
4196 
4197 	memset(&info, 0, sizeof(info));
4198 	info.type = map->map_type;
4199 	info.id = map->id;
4200 	info.key_size = map->key_size;
4201 	info.value_size = map->value_size;
4202 	info.max_entries = map->max_entries;
4203 	info.map_flags = map->map_flags;
4204 	info.map_extra = map->map_extra;
4205 	memcpy(info.name, map->name, sizeof(map->name));
4206 
4207 	if (map->btf) {
4208 		info.btf_id = btf_obj_id(map->btf);
4209 		info.btf_key_type_id = map->btf_key_type_id;
4210 		info.btf_value_type_id = map->btf_value_type_id;
4211 	}
4212 	info.btf_vmlinux_value_type_id = map->btf_vmlinux_value_type_id;
4213 
4214 	if (bpf_map_is_dev_bound(map)) {
4215 		err = bpf_map_offload_info_fill(&info, map);
4216 		if (err)
4217 			return err;
4218 	}
4219 
4220 	if (copy_to_user(uinfo, &info, info_len) ||
4221 	    put_user(info_len, &uattr->info.info_len))
4222 		return -EFAULT;
4223 
4224 	return 0;
4225 }
4226 
4227 static int bpf_btf_get_info_by_fd(struct file *file,
4228 				  struct btf *btf,
4229 				  const union bpf_attr *attr,
4230 				  union bpf_attr __user *uattr)
4231 {
4232 	struct bpf_btf_info __user *uinfo = u64_to_user_ptr(attr->info.info);
4233 	u32 info_len = attr->info.info_len;
4234 	int err;
4235 
4236 	err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(*uinfo), info_len);
4237 	if (err)
4238 		return err;
4239 
4240 	return btf_get_info_by_fd(btf, attr, uattr);
4241 }
4242 
4243 static int bpf_link_get_info_by_fd(struct file *file,
4244 				  struct bpf_link *link,
4245 				  const union bpf_attr *attr,
4246 				  union bpf_attr __user *uattr)
4247 {
4248 	struct bpf_link_info __user *uinfo = u64_to_user_ptr(attr->info.info);
4249 	struct bpf_link_info info;
4250 	u32 info_len = attr->info.info_len;
4251 	int err;
4252 
4253 	err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len);
4254 	if (err)
4255 		return err;
4256 	info_len = min_t(u32, sizeof(info), info_len);
4257 
4258 	memset(&info, 0, sizeof(info));
4259 	if (copy_from_user(&info, uinfo, info_len))
4260 		return -EFAULT;
4261 
4262 	info.type = link->type;
4263 	info.id = link->id;
4264 	info.prog_id = link->prog->aux->id;
4265 
4266 	if (link->ops->fill_link_info) {
4267 		err = link->ops->fill_link_info(link, &info);
4268 		if (err)
4269 			return err;
4270 	}
4271 
4272 	if (copy_to_user(uinfo, &info, info_len) ||
4273 	    put_user(info_len, &uattr->info.info_len))
4274 		return -EFAULT;
4275 
4276 	return 0;
4277 }
4278 
4279 
4280 #define BPF_OBJ_GET_INFO_BY_FD_LAST_FIELD info.info
4281 
4282 static int bpf_obj_get_info_by_fd(const union bpf_attr *attr,
4283 				  union bpf_attr __user *uattr)
4284 {
4285 	int ufd = attr->info.bpf_fd;
4286 	struct fd f;
4287 	int err;
4288 
4289 	if (CHECK_ATTR(BPF_OBJ_GET_INFO_BY_FD))
4290 		return -EINVAL;
4291 
4292 	f = fdget(ufd);
4293 	if (!f.file)
4294 		return -EBADFD;
4295 
4296 	if (f.file->f_op == &bpf_prog_fops)
4297 		err = bpf_prog_get_info_by_fd(f.file, f.file->private_data, attr,
4298 					      uattr);
4299 	else if (f.file->f_op == &bpf_map_fops)
4300 		err = bpf_map_get_info_by_fd(f.file, f.file->private_data, attr,
4301 					     uattr);
4302 	else if (f.file->f_op == &btf_fops)
4303 		err = bpf_btf_get_info_by_fd(f.file, f.file->private_data, attr, uattr);
4304 	else if (f.file->f_op == &bpf_link_fops)
4305 		err = bpf_link_get_info_by_fd(f.file, f.file->private_data,
4306 					      attr, uattr);
4307 	else
4308 		err = -EINVAL;
4309 
4310 	fdput(f);
4311 	return err;
4312 }
4313 
4314 #define BPF_BTF_LOAD_LAST_FIELD btf_log_level
4315 
4316 static int bpf_btf_load(const union bpf_attr *attr, bpfptr_t uattr)
4317 {
4318 	if (CHECK_ATTR(BPF_BTF_LOAD))
4319 		return -EINVAL;
4320 
4321 	if (!bpf_capable())
4322 		return -EPERM;
4323 
4324 	return btf_new_fd(attr, uattr);
4325 }
4326 
4327 #define BPF_BTF_GET_FD_BY_ID_LAST_FIELD btf_id
4328 
4329 static int bpf_btf_get_fd_by_id(const union bpf_attr *attr)
4330 {
4331 	if (CHECK_ATTR(BPF_BTF_GET_FD_BY_ID))
4332 		return -EINVAL;
4333 
4334 	if (!capable(CAP_SYS_ADMIN))
4335 		return -EPERM;
4336 
4337 	return btf_get_fd_by_id(attr->btf_id);
4338 }
4339 
4340 static int bpf_task_fd_query_copy(const union bpf_attr *attr,
4341 				    union bpf_attr __user *uattr,
4342 				    u32 prog_id, u32 fd_type,
4343 				    const char *buf, u64 probe_offset,
4344 				    u64 probe_addr)
4345 {
4346 	char __user *ubuf = u64_to_user_ptr(attr->task_fd_query.buf);
4347 	u32 len = buf ? strlen(buf) : 0, input_len;
4348 	int err = 0;
4349 
4350 	if (put_user(len, &uattr->task_fd_query.buf_len))
4351 		return -EFAULT;
4352 	input_len = attr->task_fd_query.buf_len;
4353 	if (input_len && ubuf) {
4354 		if (!len) {
4355 			/* nothing to copy, just make ubuf NULL terminated */
4356 			char zero = '\0';
4357 
4358 			if (put_user(zero, ubuf))
4359 				return -EFAULT;
4360 		} else if (input_len >= len + 1) {
4361 			/* ubuf can hold the string with NULL terminator */
4362 			if (copy_to_user(ubuf, buf, len + 1))
4363 				return -EFAULT;
4364 		} else {
4365 			/* ubuf cannot hold the string with NULL terminator,
4366 			 * do a partial copy with NULL terminator.
4367 			 */
4368 			char zero = '\0';
4369 
4370 			err = -ENOSPC;
4371 			if (copy_to_user(ubuf, buf, input_len - 1))
4372 				return -EFAULT;
4373 			if (put_user(zero, ubuf + input_len - 1))
4374 				return -EFAULT;
4375 		}
4376 	}
4377 
4378 	if (put_user(prog_id, &uattr->task_fd_query.prog_id) ||
4379 	    put_user(fd_type, &uattr->task_fd_query.fd_type) ||
4380 	    put_user(probe_offset, &uattr->task_fd_query.probe_offset) ||
4381 	    put_user(probe_addr, &uattr->task_fd_query.probe_addr))
4382 		return -EFAULT;
4383 
4384 	return err;
4385 }
4386 
4387 #define BPF_TASK_FD_QUERY_LAST_FIELD task_fd_query.probe_addr
4388 
4389 static int bpf_task_fd_query(const union bpf_attr *attr,
4390 			     union bpf_attr __user *uattr)
4391 {
4392 	pid_t pid = attr->task_fd_query.pid;
4393 	u32 fd = attr->task_fd_query.fd;
4394 	const struct perf_event *event;
4395 	struct task_struct *task;
4396 	struct file *file;
4397 	int err;
4398 
4399 	if (CHECK_ATTR(BPF_TASK_FD_QUERY))
4400 		return -EINVAL;
4401 
4402 	if (!capable(CAP_SYS_ADMIN))
4403 		return -EPERM;
4404 
4405 	if (attr->task_fd_query.flags != 0)
4406 		return -EINVAL;
4407 
4408 	rcu_read_lock();
4409 	task = get_pid_task(find_vpid(pid), PIDTYPE_PID);
4410 	rcu_read_unlock();
4411 	if (!task)
4412 		return -ENOENT;
4413 
4414 	err = 0;
4415 	file = fget_task(task, fd);
4416 	put_task_struct(task);
4417 	if (!file)
4418 		return -EBADF;
4419 
4420 	if (file->f_op == &bpf_link_fops) {
4421 		struct bpf_link *link = file->private_data;
4422 
4423 		if (link->ops == &bpf_raw_tp_link_lops) {
4424 			struct bpf_raw_tp_link *raw_tp =
4425 				container_of(link, struct bpf_raw_tp_link, link);
4426 			struct bpf_raw_event_map *btp = raw_tp->btp;
4427 
4428 			err = bpf_task_fd_query_copy(attr, uattr,
4429 						     raw_tp->link.prog->aux->id,
4430 						     BPF_FD_TYPE_RAW_TRACEPOINT,
4431 						     btp->tp->name, 0, 0);
4432 			goto put_file;
4433 		}
4434 		goto out_not_supp;
4435 	}
4436 
4437 	event = perf_get_event(file);
4438 	if (!IS_ERR(event)) {
4439 		u64 probe_offset, probe_addr;
4440 		u32 prog_id, fd_type;
4441 		const char *buf;
4442 
4443 		err = bpf_get_perf_event_info(event, &prog_id, &fd_type,
4444 					      &buf, &probe_offset,
4445 					      &probe_addr);
4446 		if (!err)
4447 			err = bpf_task_fd_query_copy(attr, uattr, prog_id,
4448 						     fd_type, buf,
4449 						     probe_offset,
4450 						     probe_addr);
4451 		goto put_file;
4452 	}
4453 
4454 out_not_supp:
4455 	err = -ENOTSUPP;
4456 put_file:
4457 	fput(file);
4458 	return err;
4459 }
4460 
4461 #define BPF_MAP_BATCH_LAST_FIELD batch.flags
4462 
4463 #define BPF_DO_BATCH(fn)			\
4464 	do {					\
4465 		if (!fn) {			\
4466 			err = -ENOTSUPP;	\
4467 			goto err_put;		\
4468 		}				\
4469 		err = fn(map, attr, uattr);	\
4470 	} while (0)
4471 
4472 static int bpf_map_do_batch(const union bpf_attr *attr,
4473 			    union bpf_attr __user *uattr,
4474 			    int cmd)
4475 {
4476 	bool has_read  = cmd == BPF_MAP_LOOKUP_BATCH ||
4477 			 cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH;
4478 	bool has_write = cmd != BPF_MAP_LOOKUP_BATCH;
4479 	struct bpf_map *map;
4480 	int err, ufd;
4481 	struct fd f;
4482 
4483 	if (CHECK_ATTR(BPF_MAP_BATCH))
4484 		return -EINVAL;
4485 
4486 	ufd = attr->batch.map_fd;
4487 	f = fdget(ufd);
4488 	map = __bpf_map_get(f);
4489 	if (IS_ERR(map))
4490 		return PTR_ERR(map);
4491 	if (has_write)
4492 		bpf_map_write_active_inc(map);
4493 	if (has_read && !(map_get_sys_perms(map, f) & FMODE_CAN_READ)) {
4494 		err = -EPERM;
4495 		goto err_put;
4496 	}
4497 	if (has_write && !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
4498 		err = -EPERM;
4499 		goto err_put;
4500 	}
4501 
4502 	if (cmd == BPF_MAP_LOOKUP_BATCH)
4503 		BPF_DO_BATCH(map->ops->map_lookup_batch);
4504 	else if (cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH)
4505 		BPF_DO_BATCH(map->ops->map_lookup_and_delete_batch);
4506 	else if (cmd == BPF_MAP_UPDATE_BATCH)
4507 		BPF_DO_BATCH(map->ops->map_update_batch);
4508 	else
4509 		BPF_DO_BATCH(map->ops->map_delete_batch);
4510 err_put:
4511 	if (has_write)
4512 		bpf_map_write_active_dec(map);
4513 	fdput(f);
4514 	return err;
4515 }
4516 
4517 #define BPF_LINK_CREATE_LAST_FIELD link_create.kprobe_multi.cookies
4518 static int link_create(union bpf_attr *attr, bpfptr_t uattr)
4519 {
4520 	enum bpf_prog_type ptype;
4521 	struct bpf_prog *prog;
4522 	int ret;
4523 
4524 	if (CHECK_ATTR(BPF_LINK_CREATE))
4525 		return -EINVAL;
4526 
4527 	prog = bpf_prog_get(attr->link_create.prog_fd);
4528 	if (IS_ERR(prog))
4529 		return PTR_ERR(prog);
4530 
4531 	ret = bpf_prog_attach_check_attach_type(prog,
4532 						attr->link_create.attach_type);
4533 	if (ret)
4534 		goto out;
4535 
4536 	switch (prog->type) {
4537 	case BPF_PROG_TYPE_EXT:
4538 		break;
4539 	case BPF_PROG_TYPE_PERF_EVENT:
4540 	case BPF_PROG_TYPE_TRACEPOINT:
4541 		if (attr->link_create.attach_type != BPF_PERF_EVENT) {
4542 			ret = -EINVAL;
4543 			goto out;
4544 		}
4545 		break;
4546 	case BPF_PROG_TYPE_KPROBE:
4547 		if (attr->link_create.attach_type != BPF_PERF_EVENT &&
4548 		    attr->link_create.attach_type != BPF_TRACE_KPROBE_MULTI) {
4549 			ret = -EINVAL;
4550 			goto out;
4551 		}
4552 		break;
4553 	default:
4554 		ptype = attach_type_to_prog_type(attr->link_create.attach_type);
4555 		if (ptype == BPF_PROG_TYPE_UNSPEC || ptype != prog->type) {
4556 			ret = -EINVAL;
4557 			goto out;
4558 		}
4559 		break;
4560 	}
4561 
4562 	switch (prog->type) {
4563 	case BPF_PROG_TYPE_CGROUP_SKB:
4564 	case BPF_PROG_TYPE_CGROUP_SOCK:
4565 	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
4566 	case BPF_PROG_TYPE_SOCK_OPS:
4567 	case BPF_PROG_TYPE_CGROUP_DEVICE:
4568 	case BPF_PROG_TYPE_CGROUP_SYSCTL:
4569 	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
4570 		ret = cgroup_bpf_link_attach(attr, prog);
4571 		break;
4572 	case BPF_PROG_TYPE_EXT:
4573 		ret = bpf_tracing_prog_attach(prog,
4574 					      attr->link_create.target_fd,
4575 					      attr->link_create.target_btf_id,
4576 					      attr->link_create.tracing.cookie);
4577 		break;
4578 	case BPF_PROG_TYPE_LSM:
4579 	case BPF_PROG_TYPE_TRACING:
4580 		if (attr->link_create.attach_type != prog->expected_attach_type) {
4581 			ret = -EINVAL;
4582 			goto out;
4583 		}
4584 		if (prog->expected_attach_type == BPF_TRACE_RAW_TP)
4585 			ret = bpf_raw_tp_link_attach(prog, NULL);
4586 		else if (prog->expected_attach_type == BPF_TRACE_ITER)
4587 			ret = bpf_iter_link_attach(attr, uattr, prog);
4588 		else if (prog->expected_attach_type == BPF_LSM_CGROUP)
4589 			ret = cgroup_bpf_link_attach(attr, prog);
4590 		else
4591 			ret = bpf_tracing_prog_attach(prog,
4592 						      attr->link_create.target_fd,
4593 						      attr->link_create.target_btf_id,
4594 						      attr->link_create.tracing.cookie);
4595 		break;
4596 	case BPF_PROG_TYPE_FLOW_DISSECTOR:
4597 	case BPF_PROG_TYPE_SK_LOOKUP:
4598 		ret = netns_bpf_link_create(attr, prog);
4599 		break;
4600 #ifdef CONFIG_NET
4601 	case BPF_PROG_TYPE_XDP:
4602 		ret = bpf_xdp_link_attach(attr, prog);
4603 		break;
4604 #endif
4605 	case BPF_PROG_TYPE_PERF_EVENT:
4606 	case BPF_PROG_TYPE_TRACEPOINT:
4607 		ret = bpf_perf_link_attach(attr, prog);
4608 		break;
4609 	case BPF_PROG_TYPE_KPROBE:
4610 		if (attr->link_create.attach_type == BPF_PERF_EVENT)
4611 			ret = bpf_perf_link_attach(attr, prog);
4612 		else
4613 			ret = bpf_kprobe_multi_link_attach(attr, prog);
4614 		break;
4615 	default:
4616 		ret = -EINVAL;
4617 	}
4618 
4619 out:
4620 	if (ret < 0)
4621 		bpf_prog_put(prog);
4622 	return ret;
4623 }
4624 
4625 #define BPF_LINK_UPDATE_LAST_FIELD link_update.old_prog_fd
4626 
4627 static int link_update(union bpf_attr *attr)
4628 {
4629 	struct bpf_prog *old_prog = NULL, *new_prog;
4630 	struct bpf_link *link;
4631 	u32 flags;
4632 	int ret;
4633 
4634 	if (CHECK_ATTR(BPF_LINK_UPDATE))
4635 		return -EINVAL;
4636 
4637 	flags = attr->link_update.flags;
4638 	if (flags & ~BPF_F_REPLACE)
4639 		return -EINVAL;
4640 
4641 	link = bpf_link_get_from_fd(attr->link_update.link_fd);
4642 	if (IS_ERR(link))
4643 		return PTR_ERR(link);
4644 
4645 	new_prog = bpf_prog_get(attr->link_update.new_prog_fd);
4646 	if (IS_ERR(new_prog)) {
4647 		ret = PTR_ERR(new_prog);
4648 		goto out_put_link;
4649 	}
4650 
4651 	if (flags & BPF_F_REPLACE) {
4652 		old_prog = bpf_prog_get(attr->link_update.old_prog_fd);
4653 		if (IS_ERR(old_prog)) {
4654 			ret = PTR_ERR(old_prog);
4655 			old_prog = NULL;
4656 			goto out_put_progs;
4657 		}
4658 	} else if (attr->link_update.old_prog_fd) {
4659 		ret = -EINVAL;
4660 		goto out_put_progs;
4661 	}
4662 
4663 	if (link->ops->update_prog)
4664 		ret = link->ops->update_prog(link, new_prog, old_prog);
4665 	else
4666 		ret = -EINVAL;
4667 
4668 out_put_progs:
4669 	if (old_prog)
4670 		bpf_prog_put(old_prog);
4671 	if (ret)
4672 		bpf_prog_put(new_prog);
4673 out_put_link:
4674 	bpf_link_put(link);
4675 	return ret;
4676 }
4677 
4678 #define BPF_LINK_DETACH_LAST_FIELD link_detach.link_fd
4679 
4680 static int link_detach(union bpf_attr *attr)
4681 {
4682 	struct bpf_link *link;
4683 	int ret;
4684 
4685 	if (CHECK_ATTR(BPF_LINK_DETACH))
4686 		return -EINVAL;
4687 
4688 	link = bpf_link_get_from_fd(attr->link_detach.link_fd);
4689 	if (IS_ERR(link))
4690 		return PTR_ERR(link);
4691 
4692 	if (link->ops->detach)
4693 		ret = link->ops->detach(link);
4694 	else
4695 		ret = -EOPNOTSUPP;
4696 
4697 	bpf_link_put(link);
4698 	return ret;
4699 }
4700 
4701 static struct bpf_link *bpf_link_inc_not_zero(struct bpf_link *link)
4702 {
4703 	return atomic64_fetch_add_unless(&link->refcnt, 1, 0) ? link : ERR_PTR(-ENOENT);
4704 }
4705 
4706 struct bpf_link *bpf_link_by_id(u32 id)
4707 {
4708 	struct bpf_link *link;
4709 
4710 	if (!id)
4711 		return ERR_PTR(-ENOENT);
4712 
4713 	spin_lock_bh(&link_idr_lock);
4714 	/* before link is "settled", ID is 0, pretend it doesn't exist yet */
4715 	link = idr_find(&link_idr, id);
4716 	if (link) {
4717 		if (link->id)
4718 			link = bpf_link_inc_not_zero(link);
4719 		else
4720 			link = ERR_PTR(-EAGAIN);
4721 	} else {
4722 		link = ERR_PTR(-ENOENT);
4723 	}
4724 	spin_unlock_bh(&link_idr_lock);
4725 	return link;
4726 }
4727 
4728 struct bpf_link *bpf_link_get_curr_or_next(u32 *id)
4729 {
4730 	struct bpf_link *link;
4731 
4732 	spin_lock_bh(&link_idr_lock);
4733 again:
4734 	link = idr_get_next(&link_idr, id);
4735 	if (link) {
4736 		link = bpf_link_inc_not_zero(link);
4737 		if (IS_ERR(link)) {
4738 			(*id)++;
4739 			goto again;
4740 		}
4741 	}
4742 	spin_unlock_bh(&link_idr_lock);
4743 
4744 	return link;
4745 }
4746 
4747 #define BPF_LINK_GET_FD_BY_ID_LAST_FIELD link_id
4748 
4749 static int bpf_link_get_fd_by_id(const union bpf_attr *attr)
4750 {
4751 	struct bpf_link *link;
4752 	u32 id = attr->link_id;
4753 	int fd;
4754 
4755 	if (CHECK_ATTR(BPF_LINK_GET_FD_BY_ID))
4756 		return -EINVAL;
4757 
4758 	if (!capable(CAP_SYS_ADMIN))
4759 		return -EPERM;
4760 
4761 	link = bpf_link_by_id(id);
4762 	if (IS_ERR(link))
4763 		return PTR_ERR(link);
4764 
4765 	fd = bpf_link_new_fd(link);
4766 	if (fd < 0)
4767 		bpf_link_put(link);
4768 
4769 	return fd;
4770 }
4771 
4772 DEFINE_MUTEX(bpf_stats_enabled_mutex);
4773 
4774 static int bpf_stats_release(struct inode *inode, struct file *file)
4775 {
4776 	mutex_lock(&bpf_stats_enabled_mutex);
4777 	static_key_slow_dec(&bpf_stats_enabled_key.key);
4778 	mutex_unlock(&bpf_stats_enabled_mutex);
4779 	return 0;
4780 }
4781 
4782 static const struct file_operations bpf_stats_fops = {
4783 	.release = bpf_stats_release,
4784 };
4785 
4786 static int bpf_enable_runtime_stats(void)
4787 {
4788 	int fd;
4789 
4790 	mutex_lock(&bpf_stats_enabled_mutex);
4791 
4792 	/* Set a very high limit to avoid overflow */
4793 	if (static_key_count(&bpf_stats_enabled_key.key) > INT_MAX / 2) {
4794 		mutex_unlock(&bpf_stats_enabled_mutex);
4795 		return -EBUSY;
4796 	}
4797 
4798 	fd = anon_inode_getfd("bpf-stats", &bpf_stats_fops, NULL, O_CLOEXEC);
4799 	if (fd >= 0)
4800 		static_key_slow_inc(&bpf_stats_enabled_key.key);
4801 
4802 	mutex_unlock(&bpf_stats_enabled_mutex);
4803 	return fd;
4804 }
4805 
4806 #define BPF_ENABLE_STATS_LAST_FIELD enable_stats.type
4807 
4808 static int bpf_enable_stats(union bpf_attr *attr)
4809 {
4810 
4811 	if (CHECK_ATTR(BPF_ENABLE_STATS))
4812 		return -EINVAL;
4813 
4814 	if (!capable(CAP_SYS_ADMIN))
4815 		return -EPERM;
4816 
4817 	switch (attr->enable_stats.type) {
4818 	case BPF_STATS_RUN_TIME:
4819 		return bpf_enable_runtime_stats();
4820 	default:
4821 		break;
4822 	}
4823 	return -EINVAL;
4824 }
4825 
4826 #define BPF_ITER_CREATE_LAST_FIELD iter_create.flags
4827 
4828 static int bpf_iter_create(union bpf_attr *attr)
4829 {
4830 	struct bpf_link *link;
4831 	int err;
4832 
4833 	if (CHECK_ATTR(BPF_ITER_CREATE))
4834 		return -EINVAL;
4835 
4836 	if (attr->iter_create.flags)
4837 		return -EINVAL;
4838 
4839 	link = bpf_link_get_from_fd(attr->iter_create.link_fd);
4840 	if (IS_ERR(link))
4841 		return PTR_ERR(link);
4842 
4843 	err = bpf_iter_new_fd(link);
4844 	bpf_link_put(link);
4845 
4846 	return err;
4847 }
4848 
4849 #define BPF_PROG_BIND_MAP_LAST_FIELD prog_bind_map.flags
4850 
4851 static int bpf_prog_bind_map(union bpf_attr *attr)
4852 {
4853 	struct bpf_prog *prog;
4854 	struct bpf_map *map;
4855 	struct bpf_map **used_maps_old, **used_maps_new;
4856 	int i, ret = 0;
4857 
4858 	if (CHECK_ATTR(BPF_PROG_BIND_MAP))
4859 		return -EINVAL;
4860 
4861 	if (attr->prog_bind_map.flags)
4862 		return -EINVAL;
4863 
4864 	prog = bpf_prog_get(attr->prog_bind_map.prog_fd);
4865 	if (IS_ERR(prog))
4866 		return PTR_ERR(prog);
4867 
4868 	map = bpf_map_get(attr->prog_bind_map.map_fd);
4869 	if (IS_ERR(map)) {
4870 		ret = PTR_ERR(map);
4871 		goto out_prog_put;
4872 	}
4873 
4874 	mutex_lock(&prog->aux->used_maps_mutex);
4875 
4876 	used_maps_old = prog->aux->used_maps;
4877 
4878 	for (i = 0; i < prog->aux->used_map_cnt; i++)
4879 		if (used_maps_old[i] == map) {
4880 			bpf_map_put(map);
4881 			goto out_unlock;
4882 		}
4883 
4884 	used_maps_new = kmalloc_array(prog->aux->used_map_cnt + 1,
4885 				      sizeof(used_maps_new[0]),
4886 				      GFP_KERNEL);
4887 	if (!used_maps_new) {
4888 		ret = -ENOMEM;
4889 		goto out_unlock;
4890 	}
4891 
4892 	memcpy(used_maps_new, used_maps_old,
4893 	       sizeof(used_maps_old[0]) * prog->aux->used_map_cnt);
4894 	used_maps_new[prog->aux->used_map_cnt] = map;
4895 
4896 	prog->aux->used_map_cnt++;
4897 	prog->aux->used_maps = used_maps_new;
4898 
4899 	kfree(used_maps_old);
4900 
4901 out_unlock:
4902 	mutex_unlock(&prog->aux->used_maps_mutex);
4903 
4904 	if (ret)
4905 		bpf_map_put(map);
4906 out_prog_put:
4907 	bpf_prog_put(prog);
4908 	return ret;
4909 }
4910 
4911 static int __sys_bpf(int cmd, bpfptr_t uattr, unsigned int size)
4912 {
4913 	union bpf_attr attr;
4914 	bool capable;
4915 	int err;
4916 
4917 	capable = bpf_capable() || !sysctl_unprivileged_bpf_disabled;
4918 
4919 	/* Intent here is for unprivileged_bpf_disabled to block key object
4920 	 * creation commands for unprivileged users; other actions depend
4921 	 * of fd availability and access to bpffs, so are dependent on
4922 	 * object creation success.  Capabilities are later verified for
4923 	 * operations such as load and map create, so even with unprivileged
4924 	 * BPF disabled, capability checks are still carried out for these
4925 	 * and other operations.
4926 	 */
4927 	if (!capable &&
4928 	    (cmd == BPF_MAP_CREATE || cmd == BPF_PROG_LOAD))
4929 		return -EPERM;
4930 
4931 	err = bpf_check_uarg_tail_zero(uattr, sizeof(attr), size);
4932 	if (err)
4933 		return err;
4934 	size = min_t(u32, size, sizeof(attr));
4935 
4936 	/* copy attributes from user space, may be less than sizeof(bpf_attr) */
4937 	memset(&attr, 0, sizeof(attr));
4938 	if (copy_from_bpfptr(&attr, uattr, size) != 0)
4939 		return -EFAULT;
4940 
4941 	err = security_bpf(cmd, &attr, size);
4942 	if (err < 0)
4943 		return err;
4944 
4945 	switch (cmd) {
4946 	case BPF_MAP_CREATE:
4947 		err = map_create(&attr);
4948 		break;
4949 	case BPF_MAP_LOOKUP_ELEM:
4950 		err = map_lookup_elem(&attr);
4951 		break;
4952 	case BPF_MAP_UPDATE_ELEM:
4953 		err = map_update_elem(&attr, uattr);
4954 		break;
4955 	case BPF_MAP_DELETE_ELEM:
4956 		err = map_delete_elem(&attr, uattr);
4957 		break;
4958 	case BPF_MAP_GET_NEXT_KEY:
4959 		err = map_get_next_key(&attr);
4960 		break;
4961 	case BPF_MAP_FREEZE:
4962 		err = map_freeze(&attr);
4963 		break;
4964 	case BPF_PROG_LOAD:
4965 		err = bpf_prog_load(&attr, uattr);
4966 		break;
4967 	case BPF_OBJ_PIN:
4968 		err = bpf_obj_pin(&attr);
4969 		break;
4970 	case BPF_OBJ_GET:
4971 		err = bpf_obj_get(&attr);
4972 		break;
4973 	case BPF_PROG_ATTACH:
4974 		err = bpf_prog_attach(&attr);
4975 		break;
4976 	case BPF_PROG_DETACH:
4977 		err = bpf_prog_detach(&attr);
4978 		break;
4979 	case BPF_PROG_QUERY:
4980 		err = bpf_prog_query(&attr, uattr.user);
4981 		break;
4982 	case BPF_PROG_TEST_RUN:
4983 		err = bpf_prog_test_run(&attr, uattr.user);
4984 		break;
4985 	case BPF_PROG_GET_NEXT_ID:
4986 		err = bpf_obj_get_next_id(&attr, uattr.user,
4987 					  &prog_idr, &prog_idr_lock);
4988 		break;
4989 	case BPF_MAP_GET_NEXT_ID:
4990 		err = bpf_obj_get_next_id(&attr, uattr.user,
4991 					  &map_idr, &map_idr_lock);
4992 		break;
4993 	case BPF_BTF_GET_NEXT_ID:
4994 		err = bpf_obj_get_next_id(&attr, uattr.user,
4995 					  &btf_idr, &btf_idr_lock);
4996 		break;
4997 	case BPF_PROG_GET_FD_BY_ID:
4998 		err = bpf_prog_get_fd_by_id(&attr);
4999 		break;
5000 	case BPF_MAP_GET_FD_BY_ID:
5001 		err = bpf_map_get_fd_by_id(&attr);
5002 		break;
5003 	case BPF_OBJ_GET_INFO_BY_FD:
5004 		err = bpf_obj_get_info_by_fd(&attr, uattr.user);
5005 		break;
5006 	case BPF_RAW_TRACEPOINT_OPEN:
5007 		err = bpf_raw_tracepoint_open(&attr);
5008 		break;
5009 	case BPF_BTF_LOAD:
5010 		err = bpf_btf_load(&attr, uattr);
5011 		break;
5012 	case BPF_BTF_GET_FD_BY_ID:
5013 		err = bpf_btf_get_fd_by_id(&attr);
5014 		break;
5015 	case BPF_TASK_FD_QUERY:
5016 		err = bpf_task_fd_query(&attr, uattr.user);
5017 		break;
5018 	case BPF_MAP_LOOKUP_AND_DELETE_ELEM:
5019 		err = map_lookup_and_delete_elem(&attr);
5020 		break;
5021 	case BPF_MAP_LOOKUP_BATCH:
5022 		err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_LOOKUP_BATCH);
5023 		break;
5024 	case BPF_MAP_LOOKUP_AND_DELETE_BATCH:
5025 		err = bpf_map_do_batch(&attr, uattr.user,
5026 				       BPF_MAP_LOOKUP_AND_DELETE_BATCH);
5027 		break;
5028 	case BPF_MAP_UPDATE_BATCH:
5029 		err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_UPDATE_BATCH);
5030 		break;
5031 	case BPF_MAP_DELETE_BATCH:
5032 		err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_DELETE_BATCH);
5033 		break;
5034 	case BPF_LINK_CREATE:
5035 		err = link_create(&attr, uattr);
5036 		break;
5037 	case BPF_LINK_UPDATE:
5038 		err = link_update(&attr);
5039 		break;
5040 	case BPF_LINK_GET_FD_BY_ID:
5041 		err = bpf_link_get_fd_by_id(&attr);
5042 		break;
5043 	case BPF_LINK_GET_NEXT_ID:
5044 		err = bpf_obj_get_next_id(&attr, uattr.user,
5045 					  &link_idr, &link_idr_lock);
5046 		break;
5047 	case BPF_ENABLE_STATS:
5048 		err = bpf_enable_stats(&attr);
5049 		break;
5050 	case BPF_ITER_CREATE:
5051 		err = bpf_iter_create(&attr);
5052 		break;
5053 	case BPF_LINK_DETACH:
5054 		err = link_detach(&attr);
5055 		break;
5056 	case BPF_PROG_BIND_MAP:
5057 		err = bpf_prog_bind_map(&attr);
5058 		break;
5059 	default:
5060 		err = -EINVAL;
5061 		break;
5062 	}
5063 
5064 	return err;
5065 }
5066 
5067 SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size)
5068 {
5069 	return __sys_bpf(cmd, USER_BPFPTR(uattr), size);
5070 }
5071 
5072 static bool syscall_prog_is_valid_access(int off, int size,
5073 					 enum bpf_access_type type,
5074 					 const struct bpf_prog *prog,
5075 					 struct bpf_insn_access_aux *info)
5076 {
5077 	if (off < 0 || off >= U16_MAX)
5078 		return false;
5079 	if (off % size != 0)
5080 		return false;
5081 	return true;
5082 }
5083 
5084 BPF_CALL_3(bpf_sys_bpf, int, cmd, union bpf_attr *, attr, u32, attr_size)
5085 {
5086 	switch (cmd) {
5087 	case BPF_MAP_CREATE:
5088 	case BPF_MAP_DELETE_ELEM:
5089 	case BPF_MAP_UPDATE_ELEM:
5090 	case BPF_MAP_FREEZE:
5091 	case BPF_MAP_GET_FD_BY_ID:
5092 	case BPF_PROG_LOAD:
5093 	case BPF_BTF_LOAD:
5094 	case BPF_LINK_CREATE:
5095 	case BPF_RAW_TRACEPOINT_OPEN:
5096 		break;
5097 	default:
5098 		return -EINVAL;
5099 	}
5100 	return __sys_bpf(cmd, KERNEL_BPFPTR(attr), attr_size);
5101 }
5102 
5103 
5104 /* To shut up -Wmissing-prototypes.
5105  * This function is used by the kernel light skeleton
5106  * to load bpf programs when modules are loaded or during kernel boot.
5107  * See tools/lib/bpf/skel_internal.h
5108  */
5109 int kern_sys_bpf(int cmd, union bpf_attr *attr, unsigned int size);
5110 
5111 int kern_sys_bpf(int cmd, union bpf_attr *attr, unsigned int size)
5112 {
5113 	struct bpf_prog * __maybe_unused prog;
5114 	struct bpf_tramp_run_ctx __maybe_unused run_ctx;
5115 
5116 	switch (cmd) {
5117 #ifdef CONFIG_BPF_JIT /* __bpf_prog_enter_sleepable used by trampoline and JIT */
5118 	case BPF_PROG_TEST_RUN:
5119 		if (attr->test.data_in || attr->test.data_out ||
5120 		    attr->test.ctx_out || attr->test.duration ||
5121 		    attr->test.repeat || attr->test.flags)
5122 			return -EINVAL;
5123 
5124 		prog = bpf_prog_get_type(attr->test.prog_fd, BPF_PROG_TYPE_SYSCALL);
5125 		if (IS_ERR(prog))
5126 			return PTR_ERR(prog);
5127 
5128 		if (attr->test.ctx_size_in < prog->aux->max_ctx_offset ||
5129 		    attr->test.ctx_size_in > U16_MAX) {
5130 			bpf_prog_put(prog);
5131 			return -EINVAL;
5132 		}
5133 
5134 		run_ctx.bpf_cookie = 0;
5135 		run_ctx.saved_run_ctx = NULL;
5136 		if (!__bpf_prog_enter_sleepable(prog, &run_ctx)) {
5137 			/* recursion detected */
5138 			bpf_prog_put(prog);
5139 			return -EBUSY;
5140 		}
5141 		attr->test.retval = bpf_prog_run(prog, (void *) (long) attr->test.ctx_in);
5142 		__bpf_prog_exit_sleepable(prog, 0 /* bpf_prog_run does runtime stats */, &run_ctx);
5143 		bpf_prog_put(prog);
5144 		return 0;
5145 #endif
5146 	default:
5147 		return ____bpf_sys_bpf(cmd, attr, size);
5148 	}
5149 }
5150 EXPORT_SYMBOL(kern_sys_bpf);
5151 
5152 static const struct bpf_func_proto bpf_sys_bpf_proto = {
5153 	.func		= bpf_sys_bpf,
5154 	.gpl_only	= false,
5155 	.ret_type	= RET_INTEGER,
5156 	.arg1_type	= ARG_ANYTHING,
5157 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
5158 	.arg3_type	= ARG_CONST_SIZE,
5159 };
5160 
5161 const struct bpf_func_proto * __weak
5162 tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
5163 {
5164 	return bpf_base_func_proto(func_id);
5165 }
5166 
5167 BPF_CALL_1(bpf_sys_close, u32, fd)
5168 {
5169 	/* When bpf program calls this helper there should not be
5170 	 * an fdget() without matching completed fdput().
5171 	 * This helper is allowed in the following callchain only:
5172 	 * sys_bpf->prog_test_run->bpf_prog->bpf_sys_close
5173 	 */
5174 	return close_fd(fd);
5175 }
5176 
5177 static const struct bpf_func_proto bpf_sys_close_proto = {
5178 	.func		= bpf_sys_close,
5179 	.gpl_only	= false,
5180 	.ret_type	= RET_INTEGER,
5181 	.arg1_type	= ARG_ANYTHING,
5182 };
5183 
5184 BPF_CALL_4(bpf_kallsyms_lookup_name, const char *, name, int, name_sz, int, flags, u64 *, res)
5185 {
5186 	if (flags)
5187 		return -EINVAL;
5188 
5189 	if (name_sz <= 1 || name[name_sz - 1])
5190 		return -EINVAL;
5191 
5192 	if (!bpf_dump_raw_ok(current_cred()))
5193 		return -EPERM;
5194 
5195 	*res = kallsyms_lookup_name(name);
5196 	return *res ? 0 : -ENOENT;
5197 }
5198 
5199 static const struct bpf_func_proto bpf_kallsyms_lookup_name_proto = {
5200 	.func		= bpf_kallsyms_lookup_name,
5201 	.gpl_only	= false,
5202 	.ret_type	= RET_INTEGER,
5203 	.arg1_type	= ARG_PTR_TO_MEM,
5204 	.arg2_type	= ARG_CONST_SIZE_OR_ZERO,
5205 	.arg3_type	= ARG_ANYTHING,
5206 	.arg4_type	= ARG_PTR_TO_LONG,
5207 };
5208 
5209 static const struct bpf_func_proto *
5210 syscall_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
5211 {
5212 	switch (func_id) {
5213 	case BPF_FUNC_sys_bpf:
5214 		return !perfmon_capable() ? NULL : &bpf_sys_bpf_proto;
5215 	case BPF_FUNC_btf_find_by_name_kind:
5216 		return &bpf_btf_find_by_name_kind_proto;
5217 	case BPF_FUNC_sys_close:
5218 		return &bpf_sys_close_proto;
5219 	case BPF_FUNC_kallsyms_lookup_name:
5220 		return &bpf_kallsyms_lookup_name_proto;
5221 	default:
5222 		return tracing_prog_func_proto(func_id, prog);
5223 	}
5224 }
5225 
5226 const struct bpf_verifier_ops bpf_syscall_verifier_ops = {
5227 	.get_func_proto  = syscall_prog_func_proto,
5228 	.is_valid_access = syscall_prog_is_valid_access,
5229 };
5230 
5231 const struct bpf_prog_ops bpf_syscall_prog_ops = {
5232 	.test_run = bpf_prog_test_run_syscall,
5233 };
5234 
5235 #ifdef CONFIG_SYSCTL
5236 static int bpf_stats_handler(struct ctl_table *table, int write,
5237 			     void *buffer, size_t *lenp, loff_t *ppos)
5238 {
5239 	struct static_key *key = (struct static_key *)table->data;
5240 	static int saved_val;
5241 	int val, ret;
5242 	struct ctl_table tmp = {
5243 		.data   = &val,
5244 		.maxlen = sizeof(val),
5245 		.mode   = table->mode,
5246 		.extra1 = SYSCTL_ZERO,
5247 		.extra2 = SYSCTL_ONE,
5248 	};
5249 
5250 	if (write && !capable(CAP_SYS_ADMIN))
5251 		return -EPERM;
5252 
5253 	mutex_lock(&bpf_stats_enabled_mutex);
5254 	val = saved_val;
5255 	ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
5256 	if (write && !ret && val != saved_val) {
5257 		if (val)
5258 			static_key_slow_inc(key);
5259 		else
5260 			static_key_slow_dec(key);
5261 		saved_val = val;
5262 	}
5263 	mutex_unlock(&bpf_stats_enabled_mutex);
5264 	return ret;
5265 }
5266 
5267 void __weak unpriv_ebpf_notify(int new_state)
5268 {
5269 }
5270 
5271 static int bpf_unpriv_handler(struct ctl_table *table, int write,
5272 			      void *buffer, size_t *lenp, loff_t *ppos)
5273 {
5274 	int ret, unpriv_enable = *(int *)table->data;
5275 	bool locked_state = unpriv_enable == 1;
5276 	struct ctl_table tmp = *table;
5277 
5278 	if (write && !capable(CAP_SYS_ADMIN))
5279 		return -EPERM;
5280 
5281 	tmp.data = &unpriv_enable;
5282 	ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
5283 	if (write && !ret) {
5284 		if (locked_state && unpriv_enable != 1)
5285 			return -EPERM;
5286 		*(int *)table->data = unpriv_enable;
5287 	}
5288 
5289 	unpriv_ebpf_notify(unpriv_enable);
5290 
5291 	return ret;
5292 }
5293 
5294 static struct ctl_table bpf_syscall_table[] = {
5295 	{
5296 		.procname	= "unprivileged_bpf_disabled",
5297 		.data		= &sysctl_unprivileged_bpf_disabled,
5298 		.maxlen		= sizeof(sysctl_unprivileged_bpf_disabled),
5299 		.mode		= 0644,
5300 		.proc_handler	= bpf_unpriv_handler,
5301 		.extra1		= SYSCTL_ZERO,
5302 		.extra2		= SYSCTL_TWO,
5303 	},
5304 	{
5305 		.procname	= "bpf_stats_enabled",
5306 		.data		= &bpf_stats_enabled_key.key,
5307 		.maxlen		= sizeof(bpf_stats_enabled_key),
5308 		.mode		= 0644,
5309 		.proc_handler	= bpf_stats_handler,
5310 	},
5311 	{ }
5312 };
5313 
5314 static int __init bpf_syscall_sysctl_init(void)
5315 {
5316 	register_sysctl_init("kernel", bpf_syscall_table);
5317 	return 0;
5318 }
5319 late_initcall(bpf_syscall_sysctl_init);
5320 #endif /* CONFIG_SYSCTL */
5321