xref: /linux/kernel/bpf/syscall.c (revision 0ad53fe3ae82443c74ff8cfd7bd13377cc1134a3)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
3  */
4 #include <linux/bpf.h>
5 #include <linux/bpf_trace.h>
6 #include <linux/bpf_lirc.h>
7 #include <linux/bpf_verifier.h>
8 #include <linux/btf.h>
9 #include <linux/syscalls.h>
10 #include <linux/slab.h>
11 #include <linux/sched/signal.h>
12 #include <linux/vmalloc.h>
13 #include <linux/mmzone.h>
14 #include <linux/anon_inodes.h>
15 #include <linux/fdtable.h>
16 #include <linux/file.h>
17 #include <linux/fs.h>
18 #include <linux/license.h>
19 #include <linux/filter.h>
20 #include <linux/kernel.h>
21 #include <linux/idr.h>
22 #include <linux/cred.h>
23 #include <linux/timekeeping.h>
24 #include <linux/ctype.h>
25 #include <linux/nospec.h>
26 #include <linux/audit.h>
27 #include <uapi/linux/btf.h>
28 #include <linux/pgtable.h>
29 #include <linux/bpf_lsm.h>
30 #include <linux/poll.h>
31 #include <linux/bpf-netns.h>
32 #include <linux/rcupdate_trace.h>
33 #include <linux/memcontrol.h>
34 
35 #define IS_FD_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || \
36 			  (map)->map_type == BPF_MAP_TYPE_CGROUP_ARRAY || \
37 			  (map)->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS)
38 #define IS_FD_PROG_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PROG_ARRAY)
39 #define IS_FD_HASH(map) ((map)->map_type == BPF_MAP_TYPE_HASH_OF_MAPS)
40 #define IS_FD_MAP(map) (IS_FD_ARRAY(map) || IS_FD_PROG_ARRAY(map) || \
41 			IS_FD_HASH(map))
42 
43 #define BPF_OBJ_FLAG_MASK   (BPF_F_RDONLY | BPF_F_WRONLY)
44 
45 DEFINE_PER_CPU(int, bpf_prog_active);
46 static DEFINE_IDR(prog_idr);
47 static DEFINE_SPINLOCK(prog_idr_lock);
48 static DEFINE_IDR(map_idr);
49 static DEFINE_SPINLOCK(map_idr_lock);
50 static DEFINE_IDR(link_idr);
51 static DEFINE_SPINLOCK(link_idr_lock);
52 
53 int sysctl_unprivileged_bpf_disabled __read_mostly =
54 	IS_BUILTIN(CONFIG_BPF_UNPRIV_DEFAULT_OFF) ? 2 : 0;
55 
56 static const struct bpf_map_ops * const bpf_map_types[] = {
57 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type)
58 #define BPF_MAP_TYPE(_id, _ops) \
59 	[_id] = &_ops,
60 #define BPF_LINK_TYPE(_id, _name)
61 #include <linux/bpf_types.h>
62 #undef BPF_PROG_TYPE
63 #undef BPF_MAP_TYPE
64 #undef BPF_LINK_TYPE
65 };
66 
67 /*
68  * If we're handed a bigger struct than we know of, ensure all the unknown bits
69  * are 0 - i.e. new user-space does not rely on any kernel feature extensions
70  * we don't know about yet.
71  *
72  * There is a ToCToU between this function call and the following
73  * copy_from_user() call. However, this is not a concern since this function is
74  * meant to be a future-proofing of bits.
75  */
76 int bpf_check_uarg_tail_zero(bpfptr_t uaddr,
77 			     size_t expected_size,
78 			     size_t actual_size)
79 {
80 	int res;
81 
82 	if (unlikely(actual_size > PAGE_SIZE))	/* silly large */
83 		return -E2BIG;
84 
85 	if (actual_size <= expected_size)
86 		return 0;
87 
88 	if (uaddr.is_kernel)
89 		res = memchr_inv(uaddr.kernel + expected_size, 0,
90 				 actual_size - expected_size) == NULL;
91 	else
92 		res = check_zeroed_user(uaddr.user + expected_size,
93 					actual_size - expected_size);
94 	if (res < 0)
95 		return res;
96 	return res ? 0 : -E2BIG;
97 }
98 
99 const struct bpf_map_ops bpf_map_offload_ops = {
100 	.map_meta_equal = bpf_map_meta_equal,
101 	.map_alloc = bpf_map_offload_map_alloc,
102 	.map_free = bpf_map_offload_map_free,
103 	.map_check_btf = map_check_no_btf,
104 };
105 
106 static struct bpf_map *find_and_alloc_map(union bpf_attr *attr)
107 {
108 	const struct bpf_map_ops *ops;
109 	u32 type = attr->map_type;
110 	struct bpf_map *map;
111 	int err;
112 
113 	if (type >= ARRAY_SIZE(bpf_map_types))
114 		return ERR_PTR(-EINVAL);
115 	type = array_index_nospec(type, ARRAY_SIZE(bpf_map_types));
116 	ops = bpf_map_types[type];
117 	if (!ops)
118 		return ERR_PTR(-EINVAL);
119 
120 	if (ops->map_alloc_check) {
121 		err = ops->map_alloc_check(attr);
122 		if (err)
123 			return ERR_PTR(err);
124 	}
125 	if (attr->map_ifindex)
126 		ops = &bpf_map_offload_ops;
127 	map = ops->map_alloc(attr);
128 	if (IS_ERR(map))
129 		return map;
130 	map->ops = ops;
131 	map->map_type = type;
132 	return map;
133 }
134 
135 static u32 bpf_map_value_size(const struct bpf_map *map)
136 {
137 	if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
138 	    map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH ||
139 	    map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY ||
140 	    map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE)
141 		return round_up(map->value_size, 8) * num_possible_cpus();
142 	else if (IS_FD_MAP(map))
143 		return sizeof(u32);
144 	else
145 		return  map->value_size;
146 }
147 
148 static void maybe_wait_bpf_programs(struct bpf_map *map)
149 {
150 	/* Wait for any running BPF programs to complete so that
151 	 * userspace, when we return to it, knows that all programs
152 	 * that could be running use the new map value.
153 	 */
154 	if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS ||
155 	    map->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS)
156 		synchronize_rcu();
157 }
158 
159 static int bpf_map_update_value(struct bpf_map *map, struct fd f, void *key,
160 				void *value, __u64 flags)
161 {
162 	int err;
163 
164 	/* Need to create a kthread, thus must support schedule */
165 	if (bpf_map_is_dev_bound(map)) {
166 		return bpf_map_offload_update_elem(map, key, value, flags);
167 	} else if (map->map_type == BPF_MAP_TYPE_CPUMAP ||
168 		   map->map_type == BPF_MAP_TYPE_STRUCT_OPS) {
169 		return map->ops->map_update_elem(map, key, value, flags);
170 	} else if (map->map_type == BPF_MAP_TYPE_SOCKHASH ||
171 		   map->map_type == BPF_MAP_TYPE_SOCKMAP) {
172 		return sock_map_update_elem_sys(map, key, value, flags);
173 	} else if (IS_FD_PROG_ARRAY(map)) {
174 		return bpf_fd_array_map_update_elem(map, f.file, key, value,
175 						    flags);
176 	}
177 
178 	bpf_disable_instrumentation();
179 	if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
180 	    map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
181 		err = bpf_percpu_hash_update(map, key, value, flags);
182 	} else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) {
183 		err = bpf_percpu_array_update(map, key, value, flags);
184 	} else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) {
185 		err = bpf_percpu_cgroup_storage_update(map, key, value,
186 						       flags);
187 	} else if (IS_FD_ARRAY(map)) {
188 		rcu_read_lock();
189 		err = bpf_fd_array_map_update_elem(map, f.file, key, value,
190 						   flags);
191 		rcu_read_unlock();
192 	} else if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) {
193 		rcu_read_lock();
194 		err = bpf_fd_htab_map_update_elem(map, f.file, key, value,
195 						  flags);
196 		rcu_read_unlock();
197 	} else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) {
198 		/* rcu_read_lock() is not needed */
199 		err = bpf_fd_reuseport_array_update_elem(map, key, value,
200 							 flags);
201 	} else if (map->map_type == BPF_MAP_TYPE_QUEUE ||
202 		   map->map_type == BPF_MAP_TYPE_STACK) {
203 		err = map->ops->map_push_elem(map, value, flags);
204 	} else {
205 		rcu_read_lock();
206 		err = map->ops->map_update_elem(map, key, value, flags);
207 		rcu_read_unlock();
208 	}
209 	bpf_enable_instrumentation();
210 	maybe_wait_bpf_programs(map);
211 
212 	return err;
213 }
214 
215 static int bpf_map_copy_value(struct bpf_map *map, void *key, void *value,
216 			      __u64 flags)
217 {
218 	void *ptr;
219 	int err;
220 
221 	if (bpf_map_is_dev_bound(map))
222 		return bpf_map_offload_lookup_elem(map, key, value);
223 
224 	bpf_disable_instrumentation();
225 	if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
226 	    map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
227 		err = bpf_percpu_hash_copy(map, key, value);
228 	} else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) {
229 		err = bpf_percpu_array_copy(map, key, value);
230 	} else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) {
231 		err = bpf_percpu_cgroup_storage_copy(map, key, value);
232 	} else if (map->map_type == BPF_MAP_TYPE_STACK_TRACE) {
233 		err = bpf_stackmap_copy(map, key, value);
234 	} else if (IS_FD_ARRAY(map) || IS_FD_PROG_ARRAY(map)) {
235 		err = bpf_fd_array_map_lookup_elem(map, key, value);
236 	} else if (IS_FD_HASH(map)) {
237 		err = bpf_fd_htab_map_lookup_elem(map, key, value);
238 	} else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) {
239 		err = bpf_fd_reuseport_array_lookup_elem(map, key, value);
240 	} else if (map->map_type == BPF_MAP_TYPE_QUEUE ||
241 		   map->map_type == BPF_MAP_TYPE_STACK) {
242 		err = map->ops->map_peek_elem(map, value);
243 	} else if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS) {
244 		/* struct_ops map requires directly updating "value" */
245 		err = bpf_struct_ops_map_sys_lookup_elem(map, key, value);
246 	} else {
247 		rcu_read_lock();
248 		if (map->ops->map_lookup_elem_sys_only)
249 			ptr = map->ops->map_lookup_elem_sys_only(map, key);
250 		else
251 			ptr = map->ops->map_lookup_elem(map, key);
252 		if (IS_ERR(ptr)) {
253 			err = PTR_ERR(ptr);
254 		} else if (!ptr) {
255 			err = -ENOENT;
256 		} else {
257 			err = 0;
258 			if (flags & BPF_F_LOCK)
259 				/* lock 'ptr' and copy everything but lock */
260 				copy_map_value_locked(map, value, ptr, true);
261 			else
262 				copy_map_value(map, value, ptr);
263 			/* mask lock and timer, since value wasn't zero inited */
264 			check_and_init_map_value(map, value);
265 		}
266 		rcu_read_unlock();
267 	}
268 
269 	bpf_enable_instrumentation();
270 	maybe_wait_bpf_programs(map);
271 
272 	return err;
273 }
274 
275 /* Please, do not use this function outside from the map creation path
276  * (e.g. in map update path) without taking care of setting the active
277  * memory cgroup (see at bpf_map_kmalloc_node() for example).
278  */
279 static void *__bpf_map_area_alloc(u64 size, int numa_node, bool mmapable)
280 {
281 	/* We really just want to fail instead of triggering OOM killer
282 	 * under memory pressure, therefore we set __GFP_NORETRY to kmalloc,
283 	 * which is used for lower order allocation requests.
284 	 *
285 	 * It has been observed that higher order allocation requests done by
286 	 * vmalloc with __GFP_NORETRY being set might fail due to not trying
287 	 * to reclaim memory from the page cache, thus we set
288 	 * __GFP_RETRY_MAYFAIL to avoid such situations.
289 	 */
290 
291 	const gfp_t gfp = __GFP_NOWARN | __GFP_ZERO | __GFP_ACCOUNT;
292 	unsigned int flags = 0;
293 	unsigned long align = 1;
294 	void *area;
295 
296 	if (size >= SIZE_MAX)
297 		return NULL;
298 
299 	/* kmalloc()'ed memory can't be mmap()'ed */
300 	if (mmapable) {
301 		BUG_ON(!PAGE_ALIGNED(size));
302 		align = SHMLBA;
303 		flags = VM_USERMAP;
304 	} else if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) {
305 		area = kmalloc_node(size, gfp | GFP_USER | __GFP_NORETRY,
306 				    numa_node);
307 		if (area != NULL)
308 			return area;
309 	}
310 
311 	return __vmalloc_node_range(size, align, VMALLOC_START, VMALLOC_END,
312 			gfp | GFP_KERNEL | __GFP_RETRY_MAYFAIL, PAGE_KERNEL,
313 			flags, numa_node, __builtin_return_address(0));
314 }
315 
316 void *bpf_map_area_alloc(u64 size, int numa_node)
317 {
318 	return __bpf_map_area_alloc(size, numa_node, false);
319 }
320 
321 void *bpf_map_area_mmapable_alloc(u64 size, int numa_node)
322 {
323 	return __bpf_map_area_alloc(size, numa_node, true);
324 }
325 
326 void bpf_map_area_free(void *area)
327 {
328 	kvfree(area);
329 }
330 
331 static u32 bpf_map_flags_retain_permanent(u32 flags)
332 {
333 	/* Some map creation flags are not tied to the map object but
334 	 * rather to the map fd instead, so they have no meaning upon
335 	 * map object inspection since multiple file descriptors with
336 	 * different (access) properties can exist here. Thus, given
337 	 * this has zero meaning for the map itself, lets clear these
338 	 * from here.
339 	 */
340 	return flags & ~(BPF_F_RDONLY | BPF_F_WRONLY);
341 }
342 
343 void bpf_map_init_from_attr(struct bpf_map *map, union bpf_attr *attr)
344 {
345 	map->map_type = attr->map_type;
346 	map->key_size = attr->key_size;
347 	map->value_size = attr->value_size;
348 	map->max_entries = attr->max_entries;
349 	map->map_flags = bpf_map_flags_retain_permanent(attr->map_flags);
350 	map->numa_node = bpf_map_attr_numa_node(attr);
351 }
352 
353 static int bpf_map_alloc_id(struct bpf_map *map)
354 {
355 	int id;
356 
357 	idr_preload(GFP_KERNEL);
358 	spin_lock_bh(&map_idr_lock);
359 	id = idr_alloc_cyclic(&map_idr, map, 1, INT_MAX, GFP_ATOMIC);
360 	if (id > 0)
361 		map->id = id;
362 	spin_unlock_bh(&map_idr_lock);
363 	idr_preload_end();
364 
365 	if (WARN_ON_ONCE(!id))
366 		return -ENOSPC;
367 
368 	return id > 0 ? 0 : id;
369 }
370 
371 void bpf_map_free_id(struct bpf_map *map, bool do_idr_lock)
372 {
373 	unsigned long flags;
374 
375 	/* Offloaded maps are removed from the IDR store when their device
376 	 * disappears - even if someone holds an fd to them they are unusable,
377 	 * the memory is gone, all ops will fail; they are simply waiting for
378 	 * refcnt to drop to be freed.
379 	 */
380 	if (!map->id)
381 		return;
382 
383 	if (do_idr_lock)
384 		spin_lock_irqsave(&map_idr_lock, flags);
385 	else
386 		__acquire(&map_idr_lock);
387 
388 	idr_remove(&map_idr, map->id);
389 	map->id = 0;
390 
391 	if (do_idr_lock)
392 		spin_unlock_irqrestore(&map_idr_lock, flags);
393 	else
394 		__release(&map_idr_lock);
395 }
396 
397 #ifdef CONFIG_MEMCG_KMEM
398 static void bpf_map_save_memcg(struct bpf_map *map)
399 {
400 	map->memcg = get_mem_cgroup_from_mm(current->mm);
401 }
402 
403 static void bpf_map_release_memcg(struct bpf_map *map)
404 {
405 	mem_cgroup_put(map->memcg);
406 }
407 
408 void *bpf_map_kmalloc_node(const struct bpf_map *map, size_t size, gfp_t flags,
409 			   int node)
410 {
411 	struct mem_cgroup *old_memcg;
412 	void *ptr;
413 
414 	old_memcg = set_active_memcg(map->memcg);
415 	ptr = kmalloc_node(size, flags | __GFP_ACCOUNT, node);
416 	set_active_memcg(old_memcg);
417 
418 	return ptr;
419 }
420 
421 void *bpf_map_kzalloc(const struct bpf_map *map, size_t size, gfp_t flags)
422 {
423 	struct mem_cgroup *old_memcg;
424 	void *ptr;
425 
426 	old_memcg = set_active_memcg(map->memcg);
427 	ptr = kzalloc(size, flags | __GFP_ACCOUNT);
428 	set_active_memcg(old_memcg);
429 
430 	return ptr;
431 }
432 
433 void __percpu *bpf_map_alloc_percpu(const struct bpf_map *map, size_t size,
434 				    size_t align, gfp_t flags)
435 {
436 	struct mem_cgroup *old_memcg;
437 	void __percpu *ptr;
438 
439 	old_memcg = set_active_memcg(map->memcg);
440 	ptr = __alloc_percpu_gfp(size, align, flags | __GFP_ACCOUNT);
441 	set_active_memcg(old_memcg);
442 
443 	return ptr;
444 }
445 
446 #else
447 static void bpf_map_save_memcg(struct bpf_map *map)
448 {
449 }
450 
451 static void bpf_map_release_memcg(struct bpf_map *map)
452 {
453 }
454 #endif
455 
456 /* called from workqueue */
457 static void bpf_map_free_deferred(struct work_struct *work)
458 {
459 	struct bpf_map *map = container_of(work, struct bpf_map, work);
460 
461 	security_bpf_map_free(map);
462 	bpf_map_release_memcg(map);
463 	/* implementation dependent freeing */
464 	map->ops->map_free(map);
465 }
466 
467 static void bpf_map_put_uref(struct bpf_map *map)
468 {
469 	if (atomic64_dec_and_test(&map->usercnt)) {
470 		if (map->ops->map_release_uref)
471 			map->ops->map_release_uref(map);
472 	}
473 }
474 
475 /* decrement map refcnt and schedule it for freeing via workqueue
476  * (unrelying map implementation ops->map_free() might sleep)
477  */
478 static void __bpf_map_put(struct bpf_map *map, bool do_idr_lock)
479 {
480 	if (atomic64_dec_and_test(&map->refcnt)) {
481 		/* bpf_map_free_id() must be called first */
482 		bpf_map_free_id(map, do_idr_lock);
483 		btf_put(map->btf);
484 		INIT_WORK(&map->work, bpf_map_free_deferred);
485 		schedule_work(&map->work);
486 	}
487 }
488 
489 void bpf_map_put(struct bpf_map *map)
490 {
491 	__bpf_map_put(map, true);
492 }
493 EXPORT_SYMBOL_GPL(bpf_map_put);
494 
495 void bpf_map_put_with_uref(struct bpf_map *map)
496 {
497 	bpf_map_put_uref(map);
498 	bpf_map_put(map);
499 }
500 
501 static int bpf_map_release(struct inode *inode, struct file *filp)
502 {
503 	struct bpf_map *map = filp->private_data;
504 
505 	if (map->ops->map_release)
506 		map->ops->map_release(map, filp);
507 
508 	bpf_map_put_with_uref(map);
509 	return 0;
510 }
511 
512 static fmode_t map_get_sys_perms(struct bpf_map *map, struct fd f)
513 {
514 	fmode_t mode = f.file->f_mode;
515 
516 	/* Our file permissions may have been overridden by global
517 	 * map permissions facing syscall side.
518 	 */
519 	if (READ_ONCE(map->frozen))
520 		mode &= ~FMODE_CAN_WRITE;
521 	return mode;
522 }
523 
524 #ifdef CONFIG_PROC_FS
525 /* Provides an approximation of the map's memory footprint.
526  * Used only to provide a backward compatibility and display
527  * a reasonable "memlock" info.
528  */
529 static unsigned long bpf_map_memory_footprint(const struct bpf_map *map)
530 {
531 	unsigned long size;
532 
533 	size = round_up(map->key_size + bpf_map_value_size(map), 8);
534 
535 	return round_up(map->max_entries * size, PAGE_SIZE);
536 }
537 
538 static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp)
539 {
540 	const struct bpf_map *map = filp->private_data;
541 	const struct bpf_array *array;
542 	u32 type = 0, jited = 0;
543 
544 	if (map->map_type == BPF_MAP_TYPE_PROG_ARRAY) {
545 		array = container_of(map, struct bpf_array, map);
546 		type  = array->aux->type;
547 		jited = array->aux->jited;
548 	}
549 
550 	seq_printf(m,
551 		   "map_type:\t%u\n"
552 		   "key_size:\t%u\n"
553 		   "value_size:\t%u\n"
554 		   "max_entries:\t%u\n"
555 		   "map_flags:\t%#x\n"
556 		   "memlock:\t%lu\n"
557 		   "map_id:\t%u\n"
558 		   "frozen:\t%u\n",
559 		   map->map_type,
560 		   map->key_size,
561 		   map->value_size,
562 		   map->max_entries,
563 		   map->map_flags,
564 		   bpf_map_memory_footprint(map),
565 		   map->id,
566 		   READ_ONCE(map->frozen));
567 	if (type) {
568 		seq_printf(m, "owner_prog_type:\t%u\n", type);
569 		seq_printf(m, "owner_jited:\t%u\n", jited);
570 	}
571 }
572 #endif
573 
574 static ssize_t bpf_dummy_read(struct file *filp, char __user *buf, size_t siz,
575 			      loff_t *ppos)
576 {
577 	/* We need this handler such that alloc_file() enables
578 	 * f_mode with FMODE_CAN_READ.
579 	 */
580 	return -EINVAL;
581 }
582 
583 static ssize_t bpf_dummy_write(struct file *filp, const char __user *buf,
584 			       size_t siz, loff_t *ppos)
585 {
586 	/* We need this handler such that alloc_file() enables
587 	 * f_mode with FMODE_CAN_WRITE.
588 	 */
589 	return -EINVAL;
590 }
591 
592 /* called for any extra memory-mapped regions (except initial) */
593 static void bpf_map_mmap_open(struct vm_area_struct *vma)
594 {
595 	struct bpf_map *map = vma->vm_file->private_data;
596 
597 	if (vma->vm_flags & VM_MAYWRITE) {
598 		mutex_lock(&map->freeze_mutex);
599 		map->writecnt++;
600 		mutex_unlock(&map->freeze_mutex);
601 	}
602 }
603 
604 /* called for all unmapped memory region (including initial) */
605 static void bpf_map_mmap_close(struct vm_area_struct *vma)
606 {
607 	struct bpf_map *map = vma->vm_file->private_data;
608 
609 	if (vma->vm_flags & VM_MAYWRITE) {
610 		mutex_lock(&map->freeze_mutex);
611 		map->writecnt--;
612 		mutex_unlock(&map->freeze_mutex);
613 	}
614 }
615 
616 static const struct vm_operations_struct bpf_map_default_vmops = {
617 	.open		= bpf_map_mmap_open,
618 	.close		= bpf_map_mmap_close,
619 };
620 
621 static int bpf_map_mmap(struct file *filp, struct vm_area_struct *vma)
622 {
623 	struct bpf_map *map = filp->private_data;
624 	int err;
625 
626 	if (!map->ops->map_mmap || map_value_has_spin_lock(map) ||
627 	    map_value_has_timer(map))
628 		return -ENOTSUPP;
629 
630 	if (!(vma->vm_flags & VM_SHARED))
631 		return -EINVAL;
632 
633 	mutex_lock(&map->freeze_mutex);
634 
635 	if (vma->vm_flags & VM_WRITE) {
636 		if (map->frozen) {
637 			err = -EPERM;
638 			goto out;
639 		}
640 		/* map is meant to be read-only, so do not allow mapping as
641 		 * writable, because it's possible to leak a writable page
642 		 * reference and allows user-space to still modify it after
643 		 * freezing, while verifier will assume contents do not change
644 		 */
645 		if (map->map_flags & BPF_F_RDONLY_PROG) {
646 			err = -EACCES;
647 			goto out;
648 		}
649 	}
650 
651 	/* set default open/close callbacks */
652 	vma->vm_ops = &bpf_map_default_vmops;
653 	vma->vm_private_data = map;
654 	vma->vm_flags &= ~VM_MAYEXEC;
655 	if (!(vma->vm_flags & VM_WRITE))
656 		/* disallow re-mapping with PROT_WRITE */
657 		vma->vm_flags &= ~VM_MAYWRITE;
658 
659 	err = map->ops->map_mmap(map, vma);
660 	if (err)
661 		goto out;
662 
663 	if (vma->vm_flags & VM_MAYWRITE)
664 		map->writecnt++;
665 out:
666 	mutex_unlock(&map->freeze_mutex);
667 	return err;
668 }
669 
670 static __poll_t bpf_map_poll(struct file *filp, struct poll_table_struct *pts)
671 {
672 	struct bpf_map *map = filp->private_data;
673 
674 	if (map->ops->map_poll)
675 		return map->ops->map_poll(map, filp, pts);
676 
677 	return EPOLLERR;
678 }
679 
680 const struct file_operations bpf_map_fops = {
681 #ifdef CONFIG_PROC_FS
682 	.show_fdinfo	= bpf_map_show_fdinfo,
683 #endif
684 	.release	= bpf_map_release,
685 	.read		= bpf_dummy_read,
686 	.write		= bpf_dummy_write,
687 	.mmap		= bpf_map_mmap,
688 	.poll		= bpf_map_poll,
689 };
690 
691 int bpf_map_new_fd(struct bpf_map *map, int flags)
692 {
693 	int ret;
694 
695 	ret = security_bpf_map(map, OPEN_FMODE(flags));
696 	if (ret < 0)
697 		return ret;
698 
699 	return anon_inode_getfd("bpf-map", &bpf_map_fops, map,
700 				flags | O_CLOEXEC);
701 }
702 
703 int bpf_get_file_flag(int flags)
704 {
705 	if ((flags & BPF_F_RDONLY) && (flags & BPF_F_WRONLY))
706 		return -EINVAL;
707 	if (flags & BPF_F_RDONLY)
708 		return O_RDONLY;
709 	if (flags & BPF_F_WRONLY)
710 		return O_WRONLY;
711 	return O_RDWR;
712 }
713 
714 /* helper macro to check that unused fields 'union bpf_attr' are zero */
715 #define CHECK_ATTR(CMD) \
716 	memchr_inv((void *) &attr->CMD##_LAST_FIELD + \
717 		   sizeof(attr->CMD##_LAST_FIELD), 0, \
718 		   sizeof(*attr) - \
719 		   offsetof(union bpf_attr, CMD##_LAST_FIELD) - \
720 		   sizeof(attr->CMD##_LAST_FIELD)) != NULL
721 
722 /* dst and src must have at least "size" number of bytes.
723  * Return strlen on success and < 0 on error.
724  */
725 int bpf_obj_name_cpy(char *dst, const char *src, unsigned int size)
726 {
727 	const char *end = src + size;
728 	const char *orig_src = src;
729 
730 	memset(dst, 0, size);
731 	/* Copy all isalnum(), '_' and '.' chars. */
732 	while (src < end && *src) {
733 		if (!isalnum(*src) &&
734 		    *src != '_' && *src != '.')
735 			return -EINVAL;
736 		*dst++ = *src++;
737 	}
738 
739 	/* No '\0' found in "size" number of bytes */
740 	if (src == end)
741 		return -EINVAL;
742 
743 	return src - orig_src;
744 }
745 
746 int map_check_no_btf(const struct bpf_map *map,
747 		     const struct btf *btf,
748 		     const struct btf_type *key_type,
749 		     const struct btf_type *value_type)
750 {
751 	return -ENOTSUPP;
752 }
753 
754 static int map_check_btf(struct bpf_map *map, const struct btf *btf,
755 			 u32 btf_key_id, u32 btf_value_id)
756 {
757 	const struct btf_type *key_type, *value_type;
758 	u32 key_size, value_size;
759 	int ret = 0;
760 
761 	/* Some maps allow key to be unspecified. */
762 	if (btf_key_id) {
763 		key_type = btf_type_id_size(btf, &btf_key_id, &key_size);
764 		if (!key_type || key_size != map->key_size)
765 			return -EINVAL;
766 	} else {
767 		key_type = btf_type_by_id(btf, 0);
768 		if (!map->ops->map_check_btf)
769 			return -EINVAL;
770 	}
771 
772 	value_type = btf_type_id_size(btf, &btf_value_id, &value_size);
773 	if (!value_type || value_size != map->value_size)
774 		return -EINVAL;
775 
776 	map->spin_lock_off = btf_find_spin_lock(btf, value_type);
777 
778 	if (map_value_has_spin_lock(map)) {
779 		if (map->map_flags & BPF_F_RDONLY_PROG)
780 			return -EACCES;
781 		if (map->map_type != BPF_MAP_TYPE_HASH &&
782 		    map->map_type != BPF_MAP_TYPE_ARRAY &&
783 		    map->map_type != BPF_MAP_TYPE_CGROUP_STORAGE &&
784 		    map->map_type != BPF_MAP_TYPE_SK_STORAGE &&
785 		    map->map_type != BPF_MAP_TYPE_INODE_STORAGE &&
786 		    map->map_type != BPF_MAP_TYPE_TASK_STORAGE)
787 			return -ENOTSUPP;
788 		if (map->spin_lock_off + sizeof(struct bpf_spin_lock) >
789 		    map->value_size) {
790 			WARN_ONCE(1,
791 				  "verifier bug spin_lock_off %d value_size %d\n",
792 				  map->spin_lock_off, map->value_size);
793 			return -EFAULT;
794 		}
795 	}
796 
797 	map->timer_off = btf_find_timer(btf, value_type);
798 	if (map_value_has_timer(map)) {
799 		if (map->map_flags & BPF_F_RDONLY_PROG)
800 			return -EACCES;
801 		if (map->map_type != BPF_MAP_TYPE_HASH &&
802 		    map->map_type != BPF_MAP_TYPE_LRU_HASH &&
803 		    map->map_type != BPF_MAP_TYPE_ARRAY)
804 			return -EOPNOTSUPP;
805 	}
806 
807 	if (map->ops->map_check_btf)
808 		ret = map->ops->map_check_btf(map, btf, key_type, value_type);
809 
810 	return ret;
811 }
812 
813 #define BPF_MAP_CREATE_LAST_FIELD btf_vmlinux_value_type_id
814 /* called via syscall */
815 static int map_create(union bpf_attr *attr)
816 {
817 	int numa_node = bpf_map_attr_numa_node(attr);
818 	struct bpf_map *map;
819 	int f_flags;
820 	int err;
821 
822 	err = CHECK_ATTR(BPF_MAP_CREATE);
823 	if (err)
824 		return -EINVAL;
825 
826 	if (attr->btf_vmlinux_value_type_id) {
827 		if (attr->map_type != BPF_MAP_TYPE_STRUCT_OPS ||
828 		    attr->btf_key_type_id || attr->btf_value_type_id)
829 			return -EINVAL;
830 	} else if (attr->btf_key_type_id && !attr->btf_value_type_id) {
831 		return -EINVAL;
832 	}
833 
834 	f_flags = bpf_get_file_flag(attr->map_flags);
835 	if (f_flags < 0)
836 		return f_flags;
837 
838 	if (numa_node != NUMA_NO_NODE &&
839 	    ((unsigned int)numa_node >= nr_node_ids ||
840 	     !node_online(numa_node)))
841 		return -EINVAL;
842 
843 	/* find map type and init map: hashtable vs rbtree vs bloom vs ... */
844 	map = find_and_alloc_map(attr);
845 	if (IS_ERR(map))
846 		return PTR_ERR(map);
847 
848 	err = bpf_obj_name_cpy(map->name, attr->map_name,
849 			       sizeof(attr->map_name));
850 	if (err < 0)
851 		goto free_map;
852 
853 	atomic64_set(&map->refcnt, 1);
854 	atomic64_set(&map->usercnt, 1);
855 	mutex_init(&map->freeze_mutex);
856 
857 	map->spin_lock_off = -EINVAL;
858 	map->timer_off = -EINVAL;
859 	if (attr->btf_key_type_id || attr->btf_value_type_id ||
860 	    /* Even the map's value is a kernel's struct,
861 	     * the bpf_prog.o must have BTF to begin with
862 	     * to figure out the corresponding kernel's
863 	     * counter part.  Thus, attr->btf_fd has
864 	     * to be valid also.
865 	     */
866 	    attr->btf_vmlinux_value_type_id) {
867 		struct btf *btf;
868 
869 		btf = btf_get_by_fd(attr->btf_fd);
870 		if (IS_ERR(btf)) {
871 			err = PTR_ERR(btf);
872 			goto free_map;
873 		}
874 		if (btf_is_kernel(btf)) {
875 			btf_put(btf);
876 			err = -EACCES;
877 			goto free_map;
878 		}
879 		map->btf = btf;
880 
881 		if (attr->btf_value_type_id) {
882 			err = map_check_btf(map, btf, attr->btf_key_type_id,
883 					    attr->btf_value_type_id);
884 			if (err)
885 				goto free_map;
886 		}
887 
888 		map->btf_key_type_id = attr->btf_key_type_id;
889 		map->btf_value_type_id = attr->btf_value_type_id;
890 		map->btf_vmlinux_value_type_id =
891 			attr->btf_vmlinux_value_type_id;
892 	}
893 
894 	err = security_bpf_map_alloc(map);
895 	if (err)
896 		goto free_map;
897 
898 	err = bpf_map_alloc_id(map);
899 	if (err)
900 		goto free_map_sec;
901 
902 	bpf_map_save_memcg(map);
903 
904 	err = bpf_map_new_fd(map, f_flags);
905 	if (err < 0) {
906 		/* failed to allocate fd.
907 		 * bpf_map_put_with_uref() is needed because the above
908 		 * bpf_map_alloc_id() has published the map
909 		 * to the userspace and the userspace may
910 		 * have refcnt-ed it through BPF_MAP_GET_FD_BY_ID.
911 		 */
912 		bpf_map_put_with_uref(map);
913 		return err;
914 	}
915 
916 	return err;
917 
918 free_map_sec:
919 	security_bpf_map_free(map);
920 free_map:
921 	btf_put(map->btf);
922 	map->ops->map_free(map);
923 	return err;
924 }
925 
926 /* if error is returned, fd is released.
927  * On success caller should complete fd access with matching fdput()
928  */
929 struct bpf_map *__bpf_map_get(struct fd f)
930 {
931 	if (!f.file)
932 		return ERR_PTR(-EBADF);
933 	if (f.file->f_op != &bpf_map_fops) {
934 		fdput(f);
935 		return ERR_PTR(-EINVAL);
936 	}
937 
938 	return f.file->private_data;
939 }
940 
941 void bpf_map_inc(struct bpf_map *map)
942 {
943 	atomic64_inc(&map->refcnt);
944 }
945 EXPORT_SYMBOL_GPL(bpf_map_inc);
946 
947 void bpf_map_inc_with_uref(struct bpf_map *map)
948 {
949 	atomic64_inc(&map->refcnt);
950 	atomic64_inc(&map->usercnt);
951 }
952 EXPORT_SYMBOL_GPL(bpf_map_inc_with_uref);
953 
954 struct bpf_map *bpf_map_get(u32 ufd)
955 {
956 	struct fd f = fdget(ufd);
957 	struct bpf_map *map;
958 
959 	map = __bpf_map_get(f);
960 	if (IS_ERR(map))
961 		return map;
962 
963 	bpf_map_inc(map);
964 	fdput(f);
965 
966 	return map;
967 }
968 
969 struct bpf_map *bpf_map_get_with_uref(u32 ufd)
970 {
971 	struct fd f = fdget(ufd);
972 	struct bpf_map *map;
973 
974 	map = __bpf_map_get(f);
975 	if (IS_ERR(map))
976 		return map;
977 
978 	bpf_map_inc_with_uref(map);
979 	fdput(f);
980 
981 	return map;
982 }
983 
984 /* map_idr_lock should have been held */
985 static struct bpf_map *__bpf_map_inc_not_zero(struct bpf_map *map, bool uref)
986 {
987 	int refold;
988 
989 	refold = atomic64_fetch_add_unless(&map->refcnt, 1, 0);
990 	if (!refold)
991 		return ERR_PTR(-ENOENT);
992 	if (uref)
993 		atomic64_inc(&map->usercnt);
994 
995 	return map;
996 }
997 
998 struct bpf_map *bpf_map_inc_not_zero(struct bpf_map *map)
999 {
1000 	spin_lock_bh(&map_idr_lock);
1001 	map = __bpf_map_inc_not_zero(map, false);
1002 	spin_unlock_bh(&map_idr_lock);
1003 
1004 	return map;
1005 }
1006 EXPORT_SYMBOL_GPL(bpf_map_inc_not_zero);
1007 
1008 int __weak bpf_stackmap_copy(struct bpf_map *map, void *key, void *value)
1009 {
1010 	return -ENOTSUPP;
1011 }
1012 
1013 static void *__bpf_copy_key(void __user *ukey, u64 key_size)
1014 {
1015 	if (key_size)
1016 		return vmemdup_user(ukey, key_size);
1017 
1018 	if (ukey)
1019 		return ERR_PTR(-EINVAL);
1020 
1021 	return NULL;
1022 }
1023 
1024 static void *___bpf_copy_key(bpfptr_t ukey, u64 key_size)
1025 {
1026 	if (key_size)
1027 		return kvmemdup_bpfptr(ukey, key_size);
1028 
1029 	if (!bpfptr_is_null(ukey))
1030 		return ERR_PTR(-EINVAL);
1031 
1032 	return NULL;
1033 }
1034 
1035 /* last field in 'union bpf_attr' used by this command */
1036 #define BPF_MAP_LOOKUP_ELEM_LAST_FIELD flags
1037 
1038 static int map_lookup_elem(union bpf_attr *attr)
1039 {
1040 	void __user *ukey = u64_to_user_ptr(attr->key);
1041 	void __user *uvalue = u64_to_user_ptr(attr->value);
1042 	int ufd = attr->map_fd;
1043 	struct bpf_map *map;
1044 	void *key, *value;
1045 	u32 value_size;
1046 	struct fd f;
1047 	int err;
1048 
1049 	if (CHECK_ATTR(BPF_MAP_LOOKUP_ELEM))
1050 		return -EINVAL;
1051 
1052 	if (attr->flags & ~BPF_F_LOCK)
1053 		return -EINVAL;
1054 
1055 	f = fdget(ufd);
1056 	map = __bpf_map_get(f);
1057 	if (IS_ERR(map))
1058 		return PTR_ERR(map);
1059 	if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) {
1060 		err = -EPERM;
1061 		goto err_put;
1062 	}
1063 
1064 	if ((attr->flags & BPF_F_LOCK) &&
1065 	    !map_value_has_spin_lock(map)) {
1066 		err = -EINVAL;
1067 		goto err_put;
1068 	}
1069 
1070 	key = __bpf_copy_key(ukey, map->key_size);
1071 	if (IS_ERR(key)) {
1072 		err = PTR_ERR(key);
1073 		goto err_put;
1074 	}
1075 
1076 	value_size = bpf_map_value_size(map);
1077 
1078 	err = -ENOMEM;
1079 	value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN);
1080 	if (!value)
1081 		goto free_key;
1082 
1083 	err = bpf_map_copy_value(map, key, value, attr->flags);
1084 	if (err)
1085 		goto free_value;
1086 
1087 	err = -EFAULT;
1088 	if (copy_to_user(uvalue, value, value_size) != 0)
1089 		goto free_value;
1090 
1091 	err = 0;
1092 
1093 free_value:
1094 	kvfree(value);
1095 free_key:
1096 	kvfree(key);
1097 err_put:
1098 	fdput(f);
1099 	return err;
1100 }
1101 
1102 
1103 #define BPF_MAP_UPDATE_ELEM_LAST_FIELD flags
1104 
1105 static int map_update_elem(union bpf_attr *attr, bpfptr_t uattr)
1106 {
1107 	bpfptr_t ukey = make_bpfptr(attr->key, uattr.is_kernel);
1108 	bpfptr_t uvalue = make_bpfptr(attr->value, uattr.is_kernel);
1109 	int ufd = attr->map_fd;
1110 	struct bpf_map *map;
1111 	void *key, *value;
1112 	u32 value_size;
1113 	struct fd f;
1114 	int err;
1115 
1116 	if (CHECK_ATTR(BPF_MAP_UPDATE_ELEM))
1117 		return -EINVAL;
1118 
1119 	f = fdget(ufd);
1120 	map = __bpf_map_get(f);
1121 	if (IS_ERR(map))
1122 		return PTR_ERR(map);
1123 	if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
1124 		err = -EPERM;
1125 		goto err_put;
1126 	}
1127 
1128 	if ((attr->flags & BPF_F_LOCK) &&
1129 	    !map_value_has_spin_lock(map)) {
1130 		err = -EINVAL;
1131 		goto err_put;
1132 	}
1133 
1134 	key = ___bpf_copy_key(ukey, map->key_size);
1135 	if (IS_ERR(key)) {
1136 		err = PTR_ERR(key);
1137 		goto err_put;
1138 	}
1139 
1140 	value_size = bpf_map_value_size(map);
1141 
1142 	err = -ENOMEM;
1143 	value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN);
1144 	if (!value)
1145 		goto free_key;
1146 
1147 	err = -EFAULT;
1148 	if (copy_from_bpfptr(value, uvalue, value_size) != 0)
1149 		goto free_value;
1150 
1151 	err = bpf_map_update_value(map, f, key, value, attr->flags);
1152 
1153 free_value:
1154 	kvfree(value);
1155 free_key:
1156 	kvfree(key);
1157 err_put:
1158 	fdput(f);
1159 	return err;
1160 }
1161 
1162 #define BPF_MAP_DELETE_ELEM_LAST_FIELD key
1163 
1164 static int map_delete_elem(union bpf_attr *attr)
1165 {
1166 	void __user *ukey = u64_to_user_ptr(attr->key);
1167 	int ufd = attr->map_fd;
1168 	struct bpf_map *map;
1169 	struct fd f;
1170 	void *key;
1171 	int err;
1172 
1173 	if (CHECK_ATTR(BPF_MAP_DELETE_ELEM))
1174 		return -EINVAL;
1175 
1176 	f = fdget(ufd);
1177 	map = __bpf_map_get(f);
1178 	if (IS_ERR(map))
1179 		return PTR_ERR(map);
1180 	if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
1181 		err = -EPERM;
1182 		goto err_put;
1183 	}
1184 
1185 	key = __bpf_copy_key(ukey, map->key_size);
1186 	if (IS_ERR(key)) {
1187 		err = PTR_ERR(key);
1188 		goto err_put;
1189 	}
1190 
1191 	if (bpf_map_is_dev_bound(map)) {
1192 		err = bpf_map_offload_delete_elem(map, key);
1193 		goto out;
1194 	} else if (IS_FD_PROG_ARRAY(map) ||
1195 		   map->map_type == BPF_MAP_TYPE_STRUCT_OPS) {
1196 		/* These maps require sleepable context */
1197 		err = map->ops->map_delete_elem(map, key);
1198 		goto out;
1199 	}
1200 
1201 	bpf_disable_instrumentation();
1202 	rcu_read_lock();
1203 	err = map->ops->map_delete_elem(map, key);
1204 	rcu_read_unlock();
1205 	bpf_enable_instrumentation();
1206 	maybe_wait_bpf_programs(map);
1207 out:
1208 	kvfree(key);
1209 err_put:
1210 	fdput(f);
1211 	return err;
1212 }
1213 
1214 /* last field in 'union bpf_attr' used by this command */
1215 #define BPF_MAP_GET_NEXT_KEY_LAST_FIELD next_key
1216 
1217 static int map_get_next_key(union bpf_attr *attr)
1218 {
1219 	void __user *ukey = u64_to_user_ptr(attr->key);
1220 	void __user *unext_key = u64_to_user_ptr(attr->next_key);
1221 	int ufd = attr->map_fd;
1222 	struct bpf_map *map;
1223 	void *key, *next_key;
1224 	struct fd f;
1225 	int err;
1226 
1227 	if (CHECK_ATTR(BPF_MAP_GET_NEXT_KEY))
1228 		return -EINVAL;
1229 
1230 	f = fdget(ufd);
1231 	map = __bpf_map_get(f);
1232 	if (IS_ERR(map))
1233 		return PTR_ERR(map);
1234 	if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) {
1235 		err = -EPERM;
1236 		goto err_put;
1237 	}
1238 
1239 	if (ukey) {
1240 		key = __bpf_copy_key(ukey, map->key_size);
1241 		if (IS_ERR(key)) {
1242 			err = PTR_ERR(key);
1243 			goto err_put;
1244 		}
1245 	} else {
1246 		key = NULL;
1247 	}
1248 
1249 	err = -ENOMEM;
1250 	next_key = kvmalloc(map->key_size, GFP_USER);
1251 	if (!next_key)
1252 		goto free_key;
1253 
1254 	if (bpf_map_is_dev_bound(map)) {
1255 		err = bpf_map_offload_get_next_key(map, key, next_key);
1256 		goto out;
1257 	}
1258 
1259 	rcu_read_lock();
1260 	err = map->ops->map_get_next_key(map, key, next_key);
1261 	rcu_read_unlock();
1262 out:
1263 	if (err)
1264 		goto free_next_key;
1265 
1266 	err = -EFAULT;
1267 	if (copy_to_user(unext_key, next_key, map->key_size) != 0)
1268 		goto free_next_key;
1269 
1270 	err = 0;
1271 
1272 free_next_key:
1273 	kvfree(next_key);
1274 free_key:
1275 	kvfree(key);
1276 err_put:
1277 	fdput(f);
1278 	return err;
1279 }
1280 
1281 int generic_map_delete_batch(struct bpf_map *map,
1282 			     const union bpf_attr *attr,
1283 			     union bpf_attr __user *uattr)
1284 {
1285 	void __user *keys = u64_to_user_ptr(attr->batch.keys);
1286 	u32 cp, max_count;
1287 	int err = 0;
1288 	void *key;
1289 
1290 	if (attr->batch.elem_flags & ~BPF_F_LOCK)
1291 		return -EINVAL;
1292 
1293 	if ((attr->batch.elem_flags & BPF_F_LOCK) &&
1294 	    !map_value_has_spin_lock(map)) {
1295 		return -EINVAL;
1296 	}
1297 
1298 	max_count = attr->batch.count;
1299 	if (!max_count)
1300 		return 0;
1301 
1302 	key = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN);
1303 	if (!key)
1304 		return -ENOMEM;
1305 
1306 	for (cp = 0; cp < max_count; cp++) {
1307 		err = -EFAULT;
1308 		if (copy_from_user(key, keys + cp * map->key_size,
1309 				   map->key_size))
1310 			break;
1311 
1312 		if (bpf_map_is_dev_bound(map)) {
1313 			err = bpf_map_offload_delete_elem(map, key);
1314 			break;
1315 		}
1316 
1317 		bpf_disable_instrumentation();
1318 		rcu_read_lock();
1319 		err = map->ops->map_delete_elem(map, key);
1320 		rcu_read_unlock();
1321 		bpf_enable_instrumentation();
1322 		maybe_wait_bpf_programs(map);
1323 		if (err)
1324 			break;
1325 	}
1326 	if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp)))
1327 		err = -EFAULT;
1328 
1329 	kvfree(key);
1330 	return err;
1331 }
1332 
1333 int generic_map_update_batch(struct bpf_map *map,
1334 			     const union bpf_attr *attr,
1335 			     union bpf_attr __user *uattr)
1336 {
1337 	void __user *values = u64_to_user_ptr(attr->batch.values);
1338 	void __user *keys = u64_to_user_ptr(attr->batch.keys);
1339 	u32 value_size, cp, max_count;
1340 	int ufd = attr->map_fd;
1341 	void *key, *value;
1342 	struct fd f;
1343 	int err = 0;
1344 
1345 	f = fdget(ufd);
1346 	if (attr->batch.elem_flags & ~BPF_F_LOCK)
1347 		return -EINVAL;
1348 
1349 	if ((attr->batch.elem_flags & BPF_F_LOCK) &&
1350 	    !map_value_has_spin_lock(map)) {
1351 		return -EINVAL;
1352 	}
1353 
1354 	value_size = bpf_map_value_size(map);
1355 
1356 	max_count = attr->batch.count;
1357 	if (!max_count)
1358 		return 0;
1359 
1360 	key = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN);
1361 	if (!key)
1362 		return -ENOMEM;
1363 
1364 	value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN);
1365 	if (!value) {
1366 		kvfree(key);
1367 		return -ENOMEM;
1368 	}
1369 
1370 	for (cp = 0; cp < max_count; cp++) {
1371 		err = -EFAULT;
1372 		if (copy_from_user(key, keys + cp * map->key_size,
1373 		    map->key_size) ||
1374 		    copy_from_user(value, values + cp * value_size, value_size))
1375 			break;
1376 
1377 		err = bpf_map_update_value(map, f, key, value,
1378 					   attr->batch.elem_flags);
1379 
1380 		if (err)
1381 			break;
1382 	}
1383 
1384 	if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp)))
1385 		err = -EFAULT;
1386 
1387 	kvfree(value);
1388 	kvfree(key);
1389 	return err;
1390 }
1391 
1392 #define MAP_LOOKUP_RETRIES 3
1393 
1394 int generic_map_lookup_batch(struct bpf_map *map,
1395 				    const union bpf_attr *attr,
1396 				    union bpf_attr __user *uattr)
1397 {
1398 	void __user *uobatch = u64_to_user_ptr(attr->batch.out_batch);
1399 	void __user *ubatch = u64_to_user_ptr(attr->batch.in_batch);
1400 	void __user *values = u64_to_user_ptr(attr->batch.values);
1401 	void __user *keys = u64_to_user_ptr(attr->batch.keys);
1402 	void *buf, *buf_prevkey, *prev_key, *key, *value;
1403 	int err, retry = MAP_LOOKUP_RETRIES;
1404 	u32 value_size, cp, max_count;
1405 
1406 	if (attr->batch.elem_flags & ~BPF_F_LOCK)
1407 		return -EINVAL;
1408 
1409 	if ((attr->batch.elem_flags & BPF_F_LOCK) &&
1410 	    !map_value_has_spin_lock(map))
1411 		return -EINVAL;
1412 
1413 	value_size = bpf_map_value_size(map);
1414 
1415 	max_count = attr->batch.count;
1416 	if (!max_count)
1417 		return 0;
1418 
1419 	if (put_user(0, &uattr->batch.count))
1420 		return -EFAULT;
1421 
1422 	buf_prevkey = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN);
1423 	if (!buf_prevkey)
1424 		return -ENOMEM;
1425 
1426 	buf = kvmalloc(map->key_size + value_size, GFP_USER | __GFP_NOWARN);
1427 	if (!buf) {
1428 		kvfree(buf_prevkey);
1429 		return -ENOMEM;
1430 	}
1431 
1432 	err = -EFAULT;
1433 	prev_key = NULL;
1434 	if (ubatch && copy_from_user(buf_prevkey, ubatch, map->key_size))
1435 		goto free_buf;
1436 	key = buf;
1437 	value = key + map->key_size;
1438 	if (ubatch)
1439 		prev_key = buf_prevkey;
1440 
1441 	for (cp = 0; cp < max_count;) {
1442 		rcu_read_lock();
1443 		err = map->ops->map_get_next_key(map, prev_key, key);
1444 		rcu_read_unlock();
1445 		if (err)
1446 			break;
1447 		err = bpf_map_copy_value(map, key, value,
1448 					 attr->batch.elem_flags);
1449 
1450 		if (err == -ENOENT) {
1451 			if (retry) {
1452 				retry--;
1453 				continue;
1454 			}
1455 			err = -EINTR;
1456 			break;
1457 		}
1458 
1459 		if (err)
1460 			goto free_buf;
1461 
1462 		if (copy_to_user(keys + cp * map->key_size, key,
1463 				 map->key_size)) {
1464 			err = -EFAULT;
1465 			goto free_buf;
1466 		}
1467 		if (copy_to_user(values + cp * value_size, value, value_size)) {
1468 			err = -EFAULT;
1469 			goto free_buf;
1470 		}
1471 
1472 		if (!prev_key)
1473 			prev_key = buf_prevkey;
1474 
1475 		swap(prev_key, key);
1476 		retry = MAP_LOOKUP_RETRIES;
1477 		cp++;
1478 	}
1479 
1480 	if (err == -EFAULT)
1481 		goto free_buf;
1482 
1483 	if ((copy_to_user(&uattr->batch.count, &cp, sizeof(cp)) ||
1484 		    (cp && copy_to_user(uobatch, prev_key, map->key_size))))
1485 		err = -EFAULT;
1486 
1487 free_buf:
1488 	kvfree(buf_prevkey);
1489 	kvfree(buf);
1490 	return err;
1491 }
1492 
1493 #define BPF_MAP_LOOKUP_AND_DELETE_ELEM_LAST_FIELD flags
1494 
1495 static int map_lookup_and_delete_elem(union bpf_attr *attr)
1496 {
1497 	void __user *ukey = u64_to_user_ptr(attr->key);
1498 	void __user *uvalue = u64_to_user_ptr(attr->value);
1499 	int ufd = attr->map_fd;
1500 	struct bpf_map *map;
1501 	void *key, *value;
1502 	u32 value_size;
1503 	struct fd f;
1504 	int err;
1505 
1506 	if (CHECK_ATTR(BPF_MAP_LOOKUP_AND_DELETE_ELEM))
1507 		return -EINVAL;
1508 
1509 	if (attr->flags & ~BPF_F_LOCK)
1510 		return -EINVAL;
1511 
1512 	f = fdget(ufd);
1513 	map = __bpf_map_get(f);
1514 	if (IS_ERR(map))
1515 		return PTR_ERR(map);
1516 	if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ) ||
1517 	    !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
1518 		err = -EPERM;
1519 		goto err_put;
1520 	}
1521 
1522 	if (attr->flags &&
1523 	    (map->map_type == BPF_MAP_TYPE_QUEUE ||
1524 	     map->map_type == BPF_MAP_TYPE_STACK)) {
1525 		err = -EINVAL;
1526 		goto err_put;
1527 	}
1528 
1529 	if ((attr->flags & BPF_F_LOCK) &&
1530 	    !map_value_has_spin_lock(map)) {
1531 		err = -EINVAL;
1532 		goto err_put;
1533 	}
1534 
1535 	key = __bpf_copy_key(ukey, map->key_size);
1536 	if (IS_ERR(key)) {
1537 		err = PTR_ERR(key);
1538 		goto err_put;
1539 	}
1540 
1541 	value_size = bpf_map_value_size(map);
1542 
1543 	err = -ENOMEM;
1544 	value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN);
1545 	if (!value)
1546 		goto free_key;
1547 
1548 	err = -ENOTSUPP;
1549 	if (map->map_type == BPF_MAP_TYPE_QUEUE ||
1550 	    map->map_type == BPF_MAP_TYPE_STACK) {
1551 		err = map->ops->map_pop_elem(map, value);
1552 	} else if (map->map_type == BPF_MAP_TYPE_HASH ||
1553 		   map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
1554 		   map->map_type == BPF_MAP_TYPE_LRU_HASH ||
1555 		   map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
1556 		if (!bpf_map_is_dev_bound(map)) {
1557 			bpf_disable_instrumentation();
1558 			rcu_read_lock();
1559 			err = map->ops->map_lookup_and_delete_elem(map, key, value, attr->flags);
1560 			rcu_read_unlock();
1561 			bpf_enable_instrumentation();
1562 		}
1563 	}
1564 
1565 	if (err)
1566 		goto free_value;
1567 
1568 	if (copy_to_user(uvalue, value, value_size) != 0) {
1569 		err = -EFAULT;
1570 		goto free_value;
1571 	}
1572 
1573 	err = 0;
1574 
1575 free_value:
1576 	kvfree(value);
1577 free_key:
1578 	kvfree(key);
1579 err_put:
1580 	fdput(f);
1581 	return err;
1582 }
1583 
1584 #define BPF_MAP_FREEZE_LAST_FIELD map_fd
1585 
1586 static int map_freeze(const union bpf_attr *attr)
1587 {
1588 	int err = 0, ufd = attr->map_fd;
1589 	struct bpf_map *map;
1590 	struct fd f;
1591 
1592 	if (CHECK_ATTR(BPF_MAP_FREEZE))
1593 		return -EINVAL;
1594 
1595 	f = fdget(ufd);
1596 	map = __bpf_map_get(f);
1597 	if (IS_ERR(map))
1598 		return PTR_ERR(map);
1599 
1600 	if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS ||
1601 	    map_value_has_timer(map)) {
1602 		fdput(f);
1603 		return -ENOTSUPP;
1604 	}
1605 
1606 	mutex_lock(&map->freeze_mutex);
1607 
1608 	if (map->writecnt) {
1609 		err = -EBUSY;
1610 		goto err_put;
1611 	}
1612 	if (READ_ONCE(map->frozen)) {
1613 		err = -EBUSY;
1614 		goto err_put;
1615 	}
1616 	if (!bpf_capable()) {
1617 		err = -EPERM;
1618 		goto err_put;
1619 	}
1620 
1621 	WRITE_ONCE(map->frozen, true);
1622 err_put:
1623 	mutex_unlock(&map->freeze_mutex);
1624 	fdput(f);
1625 	return err;
1626 }
1627 
1628 static const struct bpf_prog_ops * const bpf_prog_types[] = {
1629 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) \
1630 	[_id] = & _name ## _prog_ops,
1631 #define BPF_MAP_TYPE(_id, _ops)
1632 #define BPF_LINK_TYPE(_id, _name)
1633 #include <linux/bpf_types.h>
1634 #undef BPF_PROG_TYPE
1635 #undef BPF_MAP_TYPE
1636 #undef BPF_LINK_TYPE
1637 };
1638 
1639 static int find_prog_type(enum bpf_prog_type type, struct bpf_prog *prog)
1640 {
1641 	const struct bpf_prog_ops *ops;
1642 
1643 	if (type >= ARRAY_SIZE(bpf_prog_types))
1644 		return -EINVAL;
1645 	type = array_index_nospec(type, ARRAY_SIZE(bpf_prog_types));
1646 	ops = bpf_prog_types[type];
1647 	if (!ops)
1648 		return -EINVAL;
1649 
1650 	if (!bpf_prog_is_dev_bound(prog->aux))
1651 		prog->aux->ops = ops;
1652 	else
1653 		prog->aux->ops = &bpf_offload_prog_ops;
1654 	prog->type = type;
1655 	return 0;
1656 }
1657 
1658 enum bpf_audit {
1659 	BPF_AUDIT_LOAD,
1660 	BPF_AUDIT_UNLOAD,
1661 	BPF_AUDIT_MAX,
1662 };
1663 
1664 static const char * const bpf_audit_str[BPF_AUDIT_MAX] = {
1665 	[BPF_AUDIT_LOAD]   = "LOAD",
1666 	[BPF_AUDIT_UNLOAD] = "UNLOAD",
1667 };
1668 
1669 static void bpf_audit_prog(const struct bpf_prog *prog, unsigned int op)
1670 {
1671 	struct audit_context *ctx = NULL;
1672 	struct audit_buffer *ab;
1673 
1674 	if (WARN_ON_ONCE(op >= BPF_AUDIT_MAX))
1675 		return;
1676 	if (audit_enabled == AUDIT_OFF)
1677 		return;
1678 	if (op == BPF_AUDIT_LOAD)
1679 		ctx = audit_context();
1680 	ab = audit_log_start(ctx, GFP_ATOMIC, AUDIT_BPF);
1681 	if (unlikely(!ab))
1682 		return;
1683 	audit_log_format(ab, "prog-id=%u op=%s",
1684 			 prog->aux->id, bpf_audit_str[op]);
1685 	audit_log_end(ab);
1686 }
1687 
1688 static int bpf_prog_alloc_id(struct bpf_prog *prog)
1689 {
1690 	int id;
1691 
1692 	idr_preload(GFP_KERNEL);
1693 	spin_lock_bh(&prog_idr_lock);
1694 	id = idr_alloc_cyclic(&prog_idr, prog, 1, INT_MAX, GFP_ATOMIC);
1695 	if (id > 0)
1696 		prog->aux->id = id;
1697 	spin_unlock_bh(&prog_idr_lock);
1698 	idr_preload_end();
1699 
1700 	/* id is in [1, INT_MAX) */
1701 	if (WARN_ON_ONCE(!id))
1702 		return -ENOSPC;
1703 
1704 	return id > 0 ? 0 : id;
1705 }
1706 
1707 void bpf_prog_free_id(struct bpf_prog *prog, bool do_idr_lock)
1708 {
1709 	unsigned long flags;
1710 
1711 	/* cBPF to eBPF migrations are currently not in the idr store.
1712 	 * Offloaded programs are removed from the store when their device
1713 	 * disappears - even if someone grabs an fd to them they are unusable,
1714 	 * simply waiting for refcnt to drop to be freed.
1715 	 */
1716 	if (!prog->aux->id)
1717 		return;
1718 
1719 	if (do_idr_lock)
1720 		spin_lock_irqsave(&prog_idr_lock, flags);
1721 	else
1722 		__acquire(&prog_idr_lock);
1723 
1724 	idr_remove(&prog_idr, prog->aux->id);
1725 	prog->aux->id = 0;
1726 
1727 	if (do_idr_lock)
1728 		spin_unlock_irqrestore(&prog_idr_lock, flags);
1729 	else
1730 		__release(&prog_idr_lock);
1731 }
1732 
1733 static void __bpf_prog_put_rcu(struct rcu_head *rcu)
1734 {
1735 	struct bpf_prog_aux *aux = container_of(rcu, struct bpf_prog_aux, rcu);
1736 
1737 	kvfree(aux->func_info);
1738 	kfree(aux->func_info_aux);
1739 	free_uid(aux->user);
1740 	security_bpf_prog_free(aux);
1741 	bpf_prog_free(aux->prog);
1742 }
1743 
1744 static void __bpf_prog_put_noref(struct bpf_prog *prog, bool deferred)
1745 {
1746 	bpf_prog_kallsyms_del_all(prog);
1747 	btf_put(prog->aux->btf);
1748 	kvfree(prog->aux->jited_linfo);
1749 	kvfree(prog->aux->linfo);
1750 	kfree(prog->aux->kfunc_tab);
1751 	if (prog->aux->attach_btf)
1752 		btf_put(prog->aux->attach_btf);
1753 
1754 	if (deferred) {
1755 		if (prog->aux->sleepable)
1756 			call_rcu_tasks_trace(&prog->aux->rcu, __bpf_prog_put_rcu);
1757 		else
1758 			call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu);
1759 	} else {
1760 		__bpf_prog_put_rcu(&prog->aux->rcu);
1761 	}
1762 }
1763 
1764 static void bpf_prog_put_deferred(struct work_struct *work)
1765 {
1766 	struct bpf_prog_aux *aux;
1767 	struct bpf_prog *prog;
1768 
1769 	aux = container_of(work, struct bpf_prog_aux, work);
1770 	prog = aux->prog;
1771 	perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_UNLOAD, 0);
1772 	bpf_audit_prog(prog, BPF_AUDIT_UNLOAD);
1773 	__bpf_prog_put_noref(prog, true);
1774 }
1775 
1776 static void __bpf_prog_put(struct bpf_prog *prog, bool do_idr_lock)
1777 {
1778 	struct bpf_prog_aux *aux = prog->aux;
1779 
1780 	if (atomic64_dec_and_test(&aux->refcnt)) {
1781 		/* bpf_prog_free_id() must be called first */
1782 		bpf_prog_free_id(prog, do_idr_lock);
1783 
1784 		if (in_irq() || irqs_disabled()) {
1785 			INIT_WORK(&aux->work, bpf_prog_put_deferred);
1786 			schedule_work(&aux->work);
1787 		} else {
1788 			bpf_prog_put_deferred(&aux->work);
1789 		}
1790 	}
1791 }
1792 
1793 void bpf_prog_put(struct bpf_prog *prog)
1794 {
1795 	__bpf_prog_put(prog, true);
1796 }
1797 EXPORT_SYMBOL_GPL(bpf_prog_put);
1798 
1799 static int bpf_prog_release(struct inode *inode, struct file *filp)
1800 {
1801 	struct bpf_prog *prog = filp->private_data;
1802 
1803 	bpf_prog_put(prog);
1804 	return 0;
1805 }
1806 
1807 static void bpf_prog_get_stats(const struct bpf_prog *prog,
1808 			       struct bpf_prog_stats *stats)
1809 {
1810 	u64 nsecs = 0, cnt = 0, misses = 0;
1811 	int cpu;
1812 
1813 	for_each_possible_cpu(cpu) {
1814 		const struct bpf_prog_stats *st;
1815 		unsigned int start;
1816 		u64 tnsecs, tcnt, tmisses;
1817 
1818 		st = per_cpu_ptr(prog->stats, cpu);
1819 		do {
1820 			start = u64_stats_fetch_begin_irq(&st->syncp);
1821 			tnsecs = st->nsecs;
1822 			tcnt = st->cnt;
1823 			tmisses = st->misses;
1824 		} while (u64_stats_fetch_retry_irq(&st->syncp, start));
1825 		nsecs += tnsecs;
1826 		cnt += tcnt;
1827 		misses += tmisses;
1828 	}
1829 	stats->nsecs = nsecs;
1830 	stats->cnt = cnt;
1831 	stats->misses = misses;
1832 }
1833 
1834 #ifdef CONFIG_PROC_FS
1835 static void bpf_prog_show_fdinfo(struct seq_file *m, struct file *filp)
1836 {
1837 	const struct bpf_prog *prog = filp->private_data;
1838 	char prog_tag[sizeof(prog->tag) * 2 + 1] = { };
1839 	struct bpf_prog_stats stats;
1840 
1841 	bpf_prog_get_stats(prog, &stats);
1842 	bin2hex(prog_tag, prog->tag, sizeof(prog->tag));
1843 	seq_printf(m,
1844 		   "prog_type:\t%u\n"
1845 		   "prog_jited:\t%u\n"
1846 		   "prog_tag:\t%s\n"
1847 		   "memlock:\t%llu\n"
1848 		   "prog_id:\t%u\n"
1849 		   "run_time_ns:\t%llu\n"
1850 		   "run_cnt:\t%llu\n"
1851 		   "recursion_misses:\t%llu\n",
1852 		   prog->type,
1853 		   prog->jited,
1854 		   prog_tag,
1855 		   prog->pages * 1ULL << PAGE_SHIFT,
1856 		   prog->aux->id,
1857 		   stats.nsecs,
1858 		   stats.cnt,
1859 		   stats.misses);
1860 }
1861 #endif
1862 
1863 const struct file_operations bpf_prog_fops = {
1864 #ifdef CONFIG_PROC_FS
1865 	.show_fdinfo	= bpf_prog_show_fdinfo,
1866 #endif
1867 	.release	= bpf_prog_release,
1868 	.read		= bpf_dummy_read,
1869 	.write		= bpf_dummy_write,
1870 };
1871 
1872 int bpf_prog_new_fd(struct bpf_prog *prog)
1873 {
1874 	int ret;
1875 
1876 	ret = security_bpf_prog(prog);
1877 	if (ret < 0)
1878 		return ret;
1879 
1880 	return anon_inode_getfd("bpf-prog", &bpf_prog_fops, prog,
1881 				O_RDWR | O_CLOEXEC);
1882 }
1883 
1884 static struct bpf_prog *____bpf_prog_get(struct fd f)
1885 {
1886 	if (!f.file)
1887 		return ERR_PTR(-EBADF);
1888 	if (f.file->f_op != &bpf_prog_fops) {
1889 		fdput(f);
1890 		return ERR_PTR(-EINVAL);
1891 	}
1892 
1893 	return f.file->private_data;
1894 }
1895 
1896 void bpf_prog_add(struct bpf_prog *prog, int i)
1897 {
1898 	atomic64_add(i, &prog->aux->refcnt);
1899 }
1900 EXPORT_SYMBOL_GPL(bpf_prog_add);
1901 
1902 void bpf_prog_sub(struct bpf_prog *prog, int i)
1903 {
1904 	/* Only to be used for undoing previous bpf_prog_add() in some
1905 	 * error path. We still know that another entity in our call
1906 	 * path holds a reference to the program, thus atomic_sub() can
1907 	 * be safely used in such cases!
1908 	 */
1909 	WARN_ON(atomic64_sub_return(i, &prog->aux->refcnt) == 0);
1910 }
1911 EXPORT_SYMBOL_GPL(bpf_prog_sub);
1912 
1913 void bpf_prog_inc(struct bpf_prog *prog)
1914 {
1915 	atomic64_inc(&prog->aux->refcnt);
1916 }
1917 EXPORT_SYMBOL_GPL(bpf_prog_inc);
1918 
1919 /* prog_idr_lock should have been held */
1920 struct bpf_prog *bpf_prog_inc_not_zero(struct bpf_prog *prog)
1921 {
1922 	int refold;
1923 
1924 	refold = atomic64_fetch_add_unless(&prog->aux->refcnt, 1, 0);
1925 
1926 	if (!refold)
1927 		return ERR_PTR(-ENOENT);
1928 
1929 	return prog;
1930 }
1931 EXPORT_SYMBOL_GPL(bpf_prog_inc_not_zero);
1932 
1933 bool bpf_prog_get_ok(struct bpf_prog *prog,
1934 			    enum bpf_prog_type *attach_type, bool attach_drv)
1935 {
1936 	/* not an attachment, just a refcount inc, always allow */
1937 	if (!attach_type)
1938 		return true;
1939 
1940 	if (prog->type != *attach_type)
1941 		return false;
1942 	if (bpf_prog_is_dev_bound(prog->aux) && !attach_drv)
1943 		return false;
1944 
1945 	return true;
1946 }
1947 
1948 static struct bpf_prog *__bpf_prog_get(u32 ufd, enum bpf_prog_type *attach_type,
1949 				       bool attach_drv)
1950 {
1951 	struct fd f = fdget(ufd);
1952 	struct bpf_prog *prog;
1953 
1954 	prog = ____bpf_prog_get(f);
1955 	if (IS_ERR(prog))
1956 		return prog;
1957 	if (!bpf_prog_get_ok(prog, attach_type, attach_drv)) {
1958 		prog = ERR_PTR(-EINVAL);
1959 		goto out;
1960 	}
1961 
1962 	bpf_prog_inc(prog);
1963 out:
1964 	fdput(f);
1965 	return prog;
1966 }
1967 
1968 struct bpf_prog *bpf_prog_get(u32 ufd)
1969 {
1970 	return __bpf_prog_get(ufd, NULL, false);
1971 }
1972 
1973 struct bpf_prog *bpf_prog_get_type_dev(u32 ufd, enum bpf_prog_type type,
1974 				       bool attach_drv)
1975 {
1976 	return __bpf_prog_get(ufd, &type, attach_drv);
1977 }
1978 EXPORT_SYMBOL_GPL(bpf_prog_get_type_dev);
1979 
1980 /* Initially all BPF programs could be loaded w/o specifying
1981  * expected_attach_type. Later for some of them specifying expected_attach_type
1982  * at load time became required so that program could be validated properly.
1983  * Programs of types that are allowed to be loaded both w/ and w/o (for
1984  * backward compatibility) expected_attach_type, should have the default attach
1985  * type assigned to expected_attach_type for the latter case, so that it can be
1986  * validated later at attach time.
1987  *
1988  * bpf_prog_load_fixup_attach_type() sets expected_attach_type in @attr if
1989  * prog type requires it but has some attach types that have to be backward
1990  * compatible.
1991  */
1992 static void bpf_prog_load_fixup_attach_type(union bpf_attr *attr)
1993 {
1994 	switch (attr->prog_type) {
1995 	case BPF_PROG_TYPE_CGROUP_SOCK:
1996 		/* Unfortunately BPF_ATTACH_TYPE_UNSPEC enumeration doesn't
1997 		 * exist so checking for non-zero is the way to go here.
1998 		 */
1999 		if (!attr->expected_attach_type)
2000 			attr->expected_attach_type =
2001 				BPF_CGROUP_INET_SOCK_CREATE;
2002 		break;
2003 	case BPF_PROG_TYPE_SK_REUSEPORT:
2004 		if (!attr->expected_attach_type)
2005 			attr->expected_attach_type =
2006 				BPF_SK_REUSEPORT_SELECT;
2007 		break;
2008 	}
2009 }
2010 
2011 static int
2012 bpf_prog_load_check_attach(enum bpf_prog_type prog_type,
2013 			   enum bpf_attach_type expected_attach_type,
2014 			   struct btf *attach_btf, u32 btf_id,
2015 			   struct bpf_prog *dst_prog)
2016 {
2017 	if (btf_id) {
2018 		if (btf_id > BTF_MAX_TYPE)
2019 			return -EINVAL;
2020 
2021 		if (!attach_btf && !dst_prog)
2022 			return -EINVAL;
2023 
2024 		switch (prog_type) {
2025 		case BPF_PROG_TYPE_TRACING:
2026 		case BPF_PROG_TYPE_LSM:
2027 		case BPF_PROG_TYPE_STRUCT_OPS:
2028 		case BPF_PROG_TYPE_EXT:
2029 			break;
2030 		default:
2031 			return -EINVAL;
2032 		}
2033 	}
2034 
2035 	if (attach_btf && (!btf_id || dst_prog))
2036 		return -EINVAL;
2037 
2038 	if (dst_prog && prog_type != BPF_PROG_TYPE_TRACING &&
2039 	    prog_type != BPF_PROG_TYPE_EXT)
2040 		return -EINVAL;
2041 
2042 	switch (prog_type) {
2043 	case BPF_PROG_TYPE_CGROUP_SOCK:
2044 		switch (expected_attach_type) {
2045 		case BPF_CGROUP_INET_SOCK_CREATE:
2046 		case BPF_CGROUP_INET_SOCK_RELEASE:
2047 		case BPF_CGROUP_INET4_POST_BIND:
2048 		case BPF_CGROUP_INET6_POST_BIND:
2049 			return 0;
2050 		default:
2051 			return -EINVAL;
2052 		}
2053 	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
2054 		switch (expected_attach_type) {
2055 		case BPF_CGROUP_INET4_BIND:
2056 		case BPF_CGROUP_INET6_BIND:
2057 		case BPF_CGROUP_INET4_CONNECT:
2058 		case BPF_CGROUP_INET6_CONNECT:
2059 		case BPF_CGROUP_INET4_GETPEERNAME:
2060 		case BPF_CGROUP_INET6_GETPEERNAME:
2061 		case BPF_CGROUP_INET4_GETSOCKNAME:
2062 		case BPF_CGROUP_INET6_GETSOCKNAME:
2063 		case BPF_CGROUP_UDP4_SENDMSG:
2064 		case BPF_CGROUP_UDP6_SENDMSG:
2065 		case BPF_CGROUP_UDP4_RECVMSG:
2066 		case BPF_CGROUP_UDP6_RECVMSG:
2067 			return 0;
2068 		default:
2069 			return -EINVAL;
2070 		}
2071 	case BPF_PROG_TYPE_CGROUP_SKB:
2072 		switch (expected_attach_type) {
2073 		case BPF_CGROUP_INET_INGRESS:
2074 		case BPF_CGROUP_INET_EGRESS:
2075 			return 0;
2076 		default:
2077 			return -EINVAL;
2078 		}
2079 	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
2080 		switch (expected_attach_type) {
2081 		case BPF_CGROUP_SETSOCKOPT:
2082 		case BPF_CGROUP_GETSOCKOPT:
2083 			return 0;
2084 		default:
2085 			return -EINVAL;
2086 		}
2087 	case BPF_PROG_TYPE_SK_LOOKUP:
2088 		if (expected_attach_type == BPF_SK_LOOKUP)
2089 			return 0;
2090 		return -EINVAL;
2091 	case BPF_PROG_TYPE_SK_REUSEPORT:
2092 		switch (expected_attach_type) {
2093 		case BPF_SK_REUSEPORT_SELECT:
2094 		case BPF_SK_REUSEPORT_SELECT_OR_MIGRATE:
2095 			return 0;
2096 		default:
2097 			return -EINVAL;
2098 		}
2099 	case BPF_PROG_TYPE_SYSCALL:
2100 	case BPF_PROG_TYPE_EXT:
2101 		if (expected_attach_type)
2102 			return -EINVAL;
2103 		fallthrough;
2104 	default:
2105 		return 0;
2106 	}
2107 }
2108 
2109 static bool is_net_admin_prog_type(enum bpf_prog_type prog_type)
2110 {
2111 	switch (prog_type) {
2112 	case BPF_PROG_TYPE_SCHED_CLS:
2113 	case BPF_PROG_TYPE_SCHED_ACT:
2114 	case BPF_PROG_TYPE_XDP:
2115 	case BPF_PROG_TYPE_LWT_IN:
2116 	case BPF_PROG_TYPE_LWT_OUT:
2117 	case BPF_PROG_TYPE_LWT_XMIT:
2118 	case BPF_PROG_TYPE_LWT_SEG6LOCAL:
2119 	case BPF_PROG_TYPE_SK_SKB:
2120 	case BPF_PROG_TYPE_SK_MSG:
2121 	case BPF_PROG_TYPE_LIRC_MODE2:
2122 	case BPF_PROG_TYPE_FLOW_DISSECTOR:
2123 	case BPF_PROG_TYPE_CGROUP_DEVICE:
2124 	case BPF_PROG_TYPE_CGROUP_SOCK:
2125 	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
2126 	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
2127 	case BPF_PROG_TYPE_CGROUP_SYSCTL:
2128 	case BPF_PROG_TYPE_SOCK_OPS:
2129 	case BPF_PROG_TYPE_EXT: /* extends any prog */
2130 		return true;
2131 	case BPF_PROG_TYPE_CGROUP_SKB:
2132 		/* always unpriv */
2133 	case BPF_PROG_TYPE_SK_REUSEPORT:
2134 		/* equivalent to SOCKET_FILTER. need CAP_BPF only */
2135 	default:
2136 		return false;
2137 	}
2138 }
2139 
2140 static bool is_perfmon_prog_type(enum bpf_prog_type prog_type)
2141 {
2142 	switch (prog_type) {
2143 	case BPF_PROG_TYPE_KPROBE:
2144 	case BPF_PROG_TYPE_TRACEPOINT:
2145 	case BPF_PROG_TYPE_PERF_EVENT:
2146 	case BPF_PROG_TYPE_RAW_TRACEPOINT:
2147 	case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE:
2148 	case BPF_PROG_TYPE_TRACING:
2149 	case BPF_PROG_TYPE_LSM:
2150 	case BPF_PROG_TYPE_STRUCT_OPS: /* has access to struct sock */
2151 	case BPF_PROG_TYPE_EXT: /* extends any prog */
2152 		return true;
2153 	default:
2154 		return false;
2155 	}
2156 }
2157 
2158 /* last field in 'union bpf_attr' used by this command */
2159 #define	BPF_PROG_LOAD_LAST_FIELD fd_array
2160 
2161 static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr)
2162 {
2163 	enum bpf_prog_type type = attr->prog_type;
2164 	struct bpf_prog *prog, *dst_prog = NULL;
2165 	struct btf *attach_btf = NULL;
2166 	int err;
2167 	char license[128];
2168 	bool is_gpl;
2169 
2170 	if (CHECK_ATTR(BPF_PROG_LOAD))
2171 		return -EINVAL;
2172 
2173 	if (attr->prog_flags & ~(BPF_F_STRICT_ALIGNMENT |
2174 				 BPF_F_ANY_ALIGNMENT |
2175 				 BPF_F_TEST_STATE_FREQ |
2176 				 BPF_F_SLEEPABLE |
2177 				 BPF_F_TEST_RND_HI32))
2178 		return -EINVAL;
2179 
2180 	if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) &&
2181 	    (attr->prog_flags & BPF_F_ANY_ALIGNMENT) &&
2182 	    !bpf_capable())
2183 		return -EPERM;
2184 
2185 	/* copy eBPF program license from user space */
2186 	if (strncpy_from_bpfptr(license,
2187 				make_bpfptr(attr->license, uattr.is_kernel),
2188 				sizeof(license) - 1) < 0)
2189 		return -EFAULT;
2190 	license[sizeof(license) - 1] = 0;
2191 
2192 	/* eBPF programs must be GPL compatible to use GPL-ed functions */
2193 	is_gpl = license_is_gpl_compatible(license);
2194 
2195 	if (attr->insn_cnt == 0 ||
2196 	    attr->insn_cnt > (bpf_capable() ? BPF_COMPLEXITY_LIMIT_INSNS : BPF_MAXINSNS))
2197 		return -E2BIG;
2198 	if (type != BPF_PROG_TYPE_SOCKET_FILTER &&
2199 	    type != BPF_PROG_TYPE_CGROUP_SKB &&
2200 	    !bpf_capable())
2201 		return -EPERM;
2202 
2203 	if (is_net_admin_prog_type(type) && !capable(CAP_NET_ADMIN) && !capable(CAP_SYS_ADMIN))
2204 		return -EPERM;
2205 	if (is_perfmon_prog_type(type) && !perfmon_capable())
2206 		return -EPERM;
2207 
2208 	/* attach_prog_fd/attach_btf_obj_fd can specify fd of either bpf_prog
2209 	 * or btf, we need to check which one it is
2210 	 */
2211 	if (attr->attach_prog_fd) {
2212 		dst_prog = bpf_prog_get(attr->attach_prog_fd);
2213 		if (IS_ERR(dst_prog)) {
2214 			dst_prog = NULL;
2215 			attach_btf = btf_get_by_fd(attr->attach_btf_obj_fd);
2216 			if (IS_ERR(attach_btf))
2217 				return -EINVAL;
2218 			if (!btf_is_kernel(attach_btf)) {
2219 				/* attaching through specifying bpf_prog's BTF
2220 				 * objects directly might be supported eventually
2221 				 */
2222 				btf_put(attach_btf);
2223 				return -ENOTSUPP;
2224 			}
2225 		}
2226 	} else if (attr->attach_btf_id) {
2227 		/* fall back to vmlinux BTF, if BTF type ID is specified */
2228 		attach_btf = bpf_get_btf_vmlinux();
2229 		if (IS_ERR(attach_btf))
2230 			return PTR_ERR(attach_btf);
2231 		if (!attach_btf)
2232 			return -EINVAL;
2233 		btf_get(attach_btf);
2234 	}
2235 
2236 	bpf_prog_load_fixup_attach_type(attr);
2237 	if (bpf_prog_load_check_attach(type, attr->expected_attach_type,
2238 				       attach_btf, attr->attach_btf_id,
2239 				       dst_prog)) {
2240 		if (dst_prog)
2241 			bpf_prog_put(dst_prog);
2242 		if (attach_btf)
2243 			btf_put(attach_btf);
2244 		return -EINVAL;
2245 	}
2246 
2247 	/* plain bpf_prog allocation */
2248 	prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER);
2249 	if (!prog) {
2250 		if (dst_prog)
2251 			bpf_prog_put(dst_prog);
2252 		if (attach_btf)
2253 			btf_put(attach_btf);
2254 		return -ENOMEM;
2255 	}
2256 
2257 	prog->expected_attach_type = attr->expected_attach_type;
2258 	prog->aux->attach_btf = attach_btf;
2259 	prog->aux->attach_btf_id = attr->attach_btf_id;
2260 	prog->aux->dst_prog = dst_prog;
2261 	prog->aux->offload_requested = !!attr->prog_ifindex;
2262 	prog->aux->sleepable = attr->prog_flags & BPF_F_SLEEPABLE;
2263 
2264 	err = security_bpf_prog_alloc(prog->aux);
2265 	if (err)
2266 		goto free_prog;
2267 
2268 	prog->aux->user = get_current_user();
2269 	prog->len = attr->insn_cnt;
2270 
2271 	err = -EFAULT;
2272 	if (copy_from_bpfptr(prog->insns,
2273 			     make_bpfptr(attr->insns, uattr.is_kernel),
2274 			     bpf_prog_insn_size(prog)) != 0)
2275 		goto free_prog_sec;
2276 
2277 	prog->orig_prog = NULL;
2278 	prog->jited = 0;
2279 
2280 	atomic64_set(&prog->aux->refcnt, 1);
2281 	prog->gpl_compatible = is_gpl ? 1 : 0;
2282 
2283 	if (bpf_prog_is_dev_bound(prog->aux)) {
2284 		err = bpf_prog_offload_init(prog, attr);
2285 		if (err)
2286 			goto free_prog_sec;
2287 	}
2288 
2289 	/* find program type: socket_filter vs tracing_filter */
2290 	err = find_prog_type(type, prog);
2291 	if (err < 0)
2292 		goto free_prog_sec;
2293 
2294 	prog->aux->load_time = ktime_get_boottime_ns();
2295 	err = bpf_obj_name_cpy(prog->aux->name, attr->prog_name,
2296 			       sizeof(attr->prog_name));
2297 	if (err < 0)
2298 		goto free_prog_sec;
2299 
2300 	/* run eBPF verifier */
2301 	err = bpf_check(&prog, attr, uattr);
2302 	if (err < 0)
2303 		goto free_used_maps;
2304 
2305 	prog = bpf_prog_select_runtime(prog, &err);
2306 	if (err < 0)
2307 		goto free_used_maps;
2308 
2309 	err = bpf_prog_alloc_id(prog);
2310 	if (err)
2311 		goto free_used_maps;
2312 
2313 	/* Upon success of bpf_prog_alloc_id(), the BPF prog is
2314 	 * effectively publicly exposed. However, retrieving via
2315 	 * bpf_prog_get_fd_by_id() will take another reference,
2316 	 * therefore it cannot be gone underneath us.
2317 	 *
2318 	 * Only for the time /after/ successful bpf_prog_new_fd()
2319 	 * and before returning to userspace, we might just hold
2320 	 * one reference and any parallel close on that fd could
2321 	 * rip everything out. Hence, below notifications must
2322 	 * happen before bpf_prog_new_fd().
2323 	 *
2324 	 * Also, any failure handling from this point onwards must
2325 	 * be using bpf_prog_put() given the program is exposed.
2326 	 */
2327 	bpf_prog_kallsyms_add(prog);
2328 	perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_LOAD, 0);
2329 	bpf_audit_prog(prog, BPF_AUDIT_LOAD);
2330 
2331 	err = bpf_prog_new_fd(prog);
2332 	if (err < 0)
2333 		bpf_prog_put(prog);
2334 	return err;
2335 
2336 free_used_maps:
2337 	/* In case we have subprogs, we need to wait for a grace
2338 	 * period before we can tear down JIT memory since symbols
2339 	 * are already exposed under kallsyms.
2340 	 */
2341 	__bpf_prog_put_noref(prog, prog->aux->func_cnt);
2342 	return err;
2343 free_prog_sec:
2344 	free_uid(prog->aux->user);
2345 	security_bpf_prog_free(prog->aux);
2346 free_prog:
2347 	if (prog->aux->attach_btf)
2348 		btf_put(prog->aux->attach_btf);
2349 	bpf_prog_free(prog);
2350 	return err;
2351 }
2352 
2353 #define BPF_OBJ_LAST_FIELD file_flags
2354 
2355 static int bpf_obj_pin(const union bpf_attr *attr)
2356 {
2357 	if (CHECK_ATTR(BPF_OBJ) || attr->file_flags != 0)
2358 		return -EINVAL;
2359 
2360 	return bpf_obj_pin_user(attr->bpf_fd, u64_to_user_ptr(attr->pathname));
2361 }
2362 
2363 static int bpf_obj_get(const union bpf_attr *attr)
2364 {
2365 	if (CHECK_ATTR(BPF_OBJ) || attr->bpf_fd != 0 ||
2366 	    attr->file_flags & ~BPF_OBJ_FLAG_MASK)
2367 		return -EINVAL;
2368 
2369 	return bpf_obj_get_user(u64_to_user_ptr(attr->pathname),
2370 				attr->file_flags);
2371 }
2372 
2373 void bpf_link_init(struct bpf_link *link, enum bpf_link_type type,
2374 		   const struct bpf_link_ops *ops, struct bpf_prog *prog)
2375 {
2376 	atomic64_set(&link->refcnt, 1);
2377 	link->type = type;
2378 	link->id = 0;
2379 	link->ops = ops;
2380 	link->prog = prog;
2381 }
2382 
2383 static void bpf_link_free_id(int id)
2384 {
2385 	if (!id)
2386 		return;
2387 
2388 	spin_lock_bh(&link_idr_lock);
2389 	idr_remove(&link_idr, id);
2390 	spin_unlock_bh(&link_idr_lock);
2391 }
2392 
2393 /* Clean up bpf_link and corresponding anon_inode file and FD. After
2394  * anon_inode is created, bpf_link can't be just kfree()'d due to deferred
2395  * anon_inode's release() call. This helper marksbpf_link as
2396  * defunct, releases anon_inode file and puts reserved FD. bpf_prog's refcnt
2397  * is not decremented, it's the responsibility of a calling code that failed
2398  * to complete bpf_link initialization.
2399  */
2400 void bpf_link_cleanup(struct bpf_link_primer *primer)
2401 {
2402 	primer->link->prog = NULL;
2403 	bpf_link_free_id(primer->id);
2404 	fput(primer->file);
2405 	put_unused_fd(primer->fd);
2406 }
2407 
2408 void bpf_link_inc(struct bpf_link *link)
2409 {
2410 	atomic64_inc(&link->refcnt);
2411 }
2412 
2413 /* bpf_link_free is guaranteed to be called from process context */
2414 static void bpf_link_free(struct bpf_link *link)
2415 {
2416 	bpf_link_free_id(link->id);
2417 	if (link->prog) {
2418 		/* detach BPF program, clean up used resources */
2419 		link->ops->release(link);
2420 		bpf_prog_put(link->prog);
2421 	}
2422 	/* free bpf_link and its containing memory */
2423 	link->ops->dealloc(link);
2424 }
2425 
2426 static void bpf_link_put_deferred(struct work_struct *work)
2427 {
2428 	struct bpf_link *link = container_of(work, struct bpf_link, work);
2429 
2430 	bpf_link_free(link);
2431 }
2432 
2433 /* bpf_link_put can be called from atomic context, but ensures that resources
2434  * are freed from process context
2435  */
2436 void bpf_link_put(struct bpf_link *link)
2437 {
2438 	if (!atomic64_dec_and_test(&link->refcnt))
2439 		return;
2440 
2441 	if (in_atomic()) {
2442 		INIT_WORK(&link->work, bpf_link_put_deferred);
2443 		schedule_work(&link->work);
2444 	} else {
2445 		bpf_link_free(link);
2446 	}
2447 }
2448 
2449 static int bpf_link_release(struct inode *inode, struct file *filp)
2450 {
2451 	struct bpf_link *link = filp->private_data;
2452 
2453 	bpf_link_put(link);
2454 	return 0;
2455 }
2456 
2457 #ifdef CONFIG_PROC_FS
2458 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type)
2459 #define BPF_MAP_TYPE(_id, _ops)
2460 #define BPF_LINK_TYPE(_id, _name) [_id] = #_name,
2461 static const char *bpf_link_type_strs[] = {
2462 	[BPF_LINK_TYPE_UNSPEC] = "<invalid>",
2463 #include <linux/bpf_types.h>
2464 };
2465 #undef BPF_PROG_TYPE
2466 #undef BPF_MAP_TYPE
2467 #undef BPF_LINK_TYPE
2468 
2469 static void bpf_link_show_fdinfo(struct seq_file *m, struct file *filp)
2470 {
2471 	const struct bpf_link *link = filp->private_data;
2472 	const struct bpf_prog *prog = link->prog;
2473 	char prog_tag[sizeof(prog->tag) * 2 + 1] = { };
2474 
2475 	bin2hex(prog_tag, prog->tag, sizeof(prog->tag));
2476 	seq_printf(m,
2477 		   "link_type:\t%s\n"
2478 		   "link_id:\t%u\n"
2479 		   "prog_tag:\t%s\n"
2480 		   "prog_id:\t%u\n",
2481 		   bpf_link_type_strs[link->type],
2482 		   link->id,
2483 		   prog_tag,
2484 		   prog->aux->id);
2485 	if (link->ops->show_fdinfo)
2486 		link->ops->show_fdinfo(link, m);
2487 }
2488 #endif
2489 
2490 static const struct file_operations bpf_link_fops = {
2491 #ifdef CONFIG_PROC_FS
2492 	.show_fdinfo	= bpf_link_show_fdinfo,
2493 #endif
2494 	.release	= bpf_link_release,
2495 	.read		= bpf_dummy_read,
2496 	.write		= bpf_dummy_write,
2497 };
2498 
2499 static int bpf_link_alloc_id(struct bpf_link *link)
2500 {
2501 	int id;
2502 
2503 	idr_preload(GFP_KERNEL);
2504 	spin_lock_bh(&link_idr_lock);
2505 	id = idr_alloc_cyclic(&link_idr, link, 1, INT_MAX, GFP_ATOMIC);
2506 	spin_unlock_bh(&link_idr_lock);
2507 	idr_preload_end();
2508 
2509 	return id;
2510 }
2511 
2512 /* Prepare bpf_link to be exposed to user-space by allocating anon_inode file,
2513  * reserving unused FD and allocating ID from link_idr. This is to be paired
2514  * with bpf_link_settle() to install FD and ID and expose bpf_link to
2515  * user-space, if bpf_link is successfully attached. If not, bpf_link and
2516  * pre-allocated resources are to be freed with bpf_cleanup() call. All the
2517  * transient state is passed around in struct bpf_link_primer.
2518  * This is preferred way to create and initialize bpf_link, especially when
2519  * there are complicated and expensive operations inbetween creating bpf_link
2520  * itself and attaching it to BPF hook. By using bpf_link_prime() and
2521  * bpf_link_settle() kernel code using bpf_link doesn't have to perform
2522  * expensive (and potentially failing) roll back operations in a rare case
2523  * that file, FD, or ID can't be allocated.
2524  */
2525 int bpf_link_prime(struct bpf_link *link, struct bpf_link_primer *primer)
2526 {
2527 	struct file *file;
2528 	int fd, id;
2529 
2530 	fd = get_unused_fd_flags(O_CLOEXEC);
2531 	if (fd < 0)
2532 		return fd;
2533 
2534 
2535 	id = bpf_link_alloc_id(link);
2536 	if (id < 0) {
2537 		put_unused_fd(fd);
2538 		return id;
2539 	}
2540 
2541 	file = anon_inode_getfile("bpf_link", &bpf_link_fops, link, O_CLOEXEC);
2542 	if (IS_ERR(file)) {
2543 		bpf_link_free_id(id);
2544 		put_unused_fd(fd);
2545 		return PTR_ERR(file);
2546 	}
2547 
2548 	primer->link = link;
2549 	primer->file = file;
2550 	primer->fd = fd;
2551 	primer->id = id;
2552 	return 0;
2553 }
2554 
2555 int bpf_link_settle(struct bpf_link_primer *primer)
2556 {
2557 	/* make bpf_link fetchable by ID */
2558 	spin_lock_bh(&link_idr_lock);
2559 	primer->link->id = primer->id;
2560 	spin_unlock_bh(&link_idr_lock);
2561 	/* make bpf_link fetchable by FD */
2562 	fd_install(primer->fd, primer->file);
2563 	/* pass through installed FD */
2564 	return primer->fd;
2565 }
2566 
2567 int bpf_link_new_fd(struct bpf_link *link)
2568 {
2569 	return anon_inode_getfd("bpf-link", &bpf_link_fops, link, O_CLOEXEC);
2570 }
2571 
2572 struct bpf_link *bpf_link_get_from_fd(u32 ufd)
2573 {
2574 	struct fd f = fdget(ufd);
2575 	struct bpf_link *link;
2576 
2577 	if (!f.file)
2578 		return ERR_PTR(-EBADF);
2579 	if (f.file->f_op != &bpf_link_fops) {
2580 		fdput(f);
2581 		return ERR_PTR(-EINVAL);
2582 	}
2583 
2584 	link = f.file->private_data;
2585 	bpf_link_inc(link);
2586 	fdput(f);
2587 
2588 	return link;
2589 }
2590 
2591 struct bpf_tracing_link {
2592 	struct bpf_link link;
2593 	enum bpf_attach_type attach_type;
2594 	struct bpf_trampoline *trampoline;
2595 	struct bpf_prog *tgt_prog;
2596 };
2597 
2598 static void bpf_tracing_link_release(struct bpf_link *link)
2599 {
2600 	struct bpf_tracing_link *tr_link =
2601 		container_of(link, struct bpf_tracing_link, link);
2602 
2603 	WARN_ON_ONCE(bpf_trampoline_unlink_prog(link->prog,
2604 						tr_link->trampoline));
2605 
2606 	bpf_trampoline_put(tr_link->trampoline);
2607 
2608 	/* tgt_prog is NULL if target is a kernel function */
2609 	if (tr_link->tgt_prog)
2610 		bpf_prog_put(tr_link->tgt_prog);
2611 }
2612 
2613 static void bpf_tracing_link_dealloc(struct bpf_link *link)
2614 {
2615 	struct bpf_tracing_link *tr_link =
2616 		container_of(link, struct bpf_tracing_link, link);
2617 
2618 	kfree(tr_link);
2619 }
2620 
2621 static void bpf_tracing_link_show_fdinfo(const struct bpf_link *link,
2622 					 struct seq_file *seq)
2623 {
2624 	struct bpf_tracing_link *tr_link =
2625 		container_of(link, struct bpf_tracing_link, link);
2626 
2627 	seq_printf(seq,
2628 		   "attach_type:\t%d\n",
2629 		   tr_link->attach_type);
2630 }
2631 
2632 static int bpf_tracing_link_fill_link_info(const struct bpf_link *link,
2633 					   struct bpf_link_info *info)
2634 {
2635 	struct bpf_tracing_link *tr_link =
2636 		container_of(link, struct bpf_tracing_link, link);
2637 
2638 	info->tracing.attach_type = tr_link->attach_type;
2639 	bpf_trampoline_unpack_key(tr_link->trampoline->key,
2640 				  &info->tracing.target_obj_id,
2641 				  &info->tracing.target_btf_id);
2642 
2643 	return 0;
2644 }
2645 
2646 static const struct bpf_link_ops bpf_tracing_link_lops = {
2647 	.release = bpf_tracing_link_release,
2648 	.dealloc = bpf_tracing_link_dealloc,
2649 	.show_fdinfo = bpf_tracing_link_show_fdinfo,
2650 	.fill_link_info = bpf_tracing_link_fill_link_info,
2651 };
2652 
2653 static int bpf_tracing_prog_attach(struct bpf_prog *prog,
2654 				   int tgt_prog_fd,
2655 				   u32 btf_id)
2656 {
2657 	struct bpf_link_primer link_primer;
2658 	struct bpf_prog *tgt_prog = NULL;
2659 	struct bpf_trampoline *tr = NULL;
2660 	struct bpf_tracing_link *link;
2661 	u64 key = 0;
2662 	int err;
2663 
2664 	switch (prog->type) {
2665 	case BPF_PROG_TYPE_TRACING:
2666 		if (prog->expected_attach_type != BPF_TRACE_FENTRY &&
2667 		    prog->expected_attach_type != BPF_TRACE_FEXIT &&
2668 		    prog->expected_attach_type != BPF_MODIFY_RETURN) {
2669 			err = -EINVAL;
2670 			goto out_put_prog;
2671 		}
2672 		break;
2673 	case BPF_PROG_TYPE_EXT:
2674 		if (prog->expected_attach_type != 0) {
2675 			err = -EINVAL;
2676 			goto out_put_prog;
2677 		}
2678 		break;
2679 	case BPF_PROG_TYPE_LSM:
2680 		if (prog->expected_attach_type != BPF_LSM_MAC) {
2681 			err = -EINVAL;
2682 			goto out_put_prog;
2683 		}
2684 		break;
2685 	default:
2686 		err = -EINVAL;
2687 		goto out_put_prog;
2688 	}
2689 
2690 	if (!!tgt_prog_fd != !!btf_id) {
2691 		err = -EINVAL;
2692 		goto out_put_prog;
2693 	}
2694 
2695 	if (tgt_prog_fd) {
2696 		/* For now we only allow new targets for BPF_PROG_TYPE_EXT */
2697 		if (prog->type != BPF_PROG_TYPE_EXT) {
2698 			err = -EINVAL;
2699 			goto out_put_prog;
2700 		}
2701 
2702 		tgt_prog = bpf_prog_get(tgt_prog_fd);
2703 		if (IS_ERR(tgt_prog)) {
2704 			err = PTR_ERR(tgt_prog);
2705 			tgt_prog = NULL;
2706 			goto out_put_prog;
2707 		}
2708 
2709 		key = bpf_trampoline_compute_key(tgt_prog, NULL, btf_id);
2710 	}
2711 
2712 	link = kzalloc(sizeof(*link), GFP_USER);
2713 	if (!link) {
2714 		err = -ENOMEM;
2715 		goto out_put_prog;
2716 	}
2717 	bpf_link_init(&link->link, BPF_LINK_TYPE_TRACING,
2718 		      &bpf_tracing_link_lops, prog);
2719 	link->attach_type = prog->expected_attach_type;
2720 
2721 	mutex_lock(&prog->aux->dst_mutex);
2722 
2723 	/* There are a few possible cases here:
2724 	 *
2725 	 * - if prog->aux->dst_trampoline is set, the program was just loaded
2726 	 *   and not yet attached to anything, so we can use the values stored
2727 	 *   in prog->aux
2728 	 *
2729 	 * - if prog->aux->dst_trampoline is NULL, the program has already been
2730          *   attached to a target and its initial target was cleared (below)
2731 	 *
2732 	 * - if tgt_prog != NULL, the caller specified tgt_prog_fd +
2733 	 *   target_btf_id using the link_create API.
2734 	 *
2735 	 * - if tgt_prog == NULL when this function was called using the old
2736 	 *   raw_tracepoint_open API, and we need a target from prog->aux
2737 	 *
2738 	 * - if prog->aux->dst_trampoline and tgt_prog is NULL, the program
2739 	 *   was detached and is going for re-attachment.
2740 	 */
2741 	if (!prog->aux->dst_trampoline && !tgt_prog) {
2742 		/*
2743 		 * Allow re-attach for TRACING and LSM programs. If it's
2744 		 * currently linked, bpf_trampoline_link_prog will fail.
2745 		 * EXT programs need to specify tgt_prog_fd, so they
2746 		 * re-attach in separate code path.
2747 		 */
2748 		if (prog->type != BPF_PROG_TYPE_TRACING &&
2749 		    prog->type != BPF_PROG_TYPE_LSM) {
2750 			err = -EINVAL;
2751 			goto out_unlock;
2752 		}
2753 		btf_id = prog->aux->attach_btf_id;
2754 		key = bpf_trampoline_compute_key(NULL, prog->aux->attach_btf, btf_id);
2755 	}
2756 
2757 	if (!prog->aux->dst_trampoline ||
2758 	    (key && key != prog->aux->dst_trampoline->key)) {
2759 		/* If there is no saved target, or the specified target is
2760 		 * different from the destination specified at load time, we
2761 		 * need a new trampoline and a check for compatibility
2762 		 */
2763 		struct bpf_attach_target_info tgt_info = {};
2764 
2765 		err = bpf_check_attach_target(NULL, prog, tgt_prog, btf_id,
2766 					      &tgt_info);
2767 		if (err)
2768 			goto out_unlock;
2769 
2770 		tr = bpf_trampoline_get(key, &tgt_info);
2771 		if (!tr) {
2772 			err = -ENOMEM;
2773 			goto out_unlock;
2774 		}
2775 	} else {
2776 		/* The caller didn't specify a target, or the target was the
2777 		 * same as the destination supplied during program load. This
2778 		 * means we can reuse the trampoline and reference from program
2779 		 * load time, and there is no need to allocate a new one. This
2780 		 * can only happen once for any program, as the saved values in
2781 		 * prog->aux are cleared below.
2782 		 */
2783 		tr = prog->aux->dst_trampoline;
2784 		tgt_prog = prog->aux->dst_prog;
2785 	}
2786 
2787 	err = bpf_link_prime(&link->link, &link_primer);
2788 	if (err)
2789 		goto out_unlock;
2790 
2791 	err = bpf_trampoline_link_prog(prog, tr);
2792 	if (err) {
2793 		bpf_link_cleanup(&link_primer);
2794 		link = NULL;
2795 		goto out_unlock;
2796 	}
2797 
2798 	link->tgt_prog = tgt_prog;
2799 	link->trampoline = tr;
2800 
2801 	/* Always clear the trampoline and target prog from prog->aux to make
2802 	 * sure the original attach destination is not kept alive after a
2803 	 * program is (re-)attached to another target.
2804 	 */
2805 	if (prog->aux->dst_prog &&
2806 	    (tgt_prog_fd || tr != prog->aux->dst_trampoline))
2807 		/* got extra prog ref from syscall, or attaching to different prog */
2808 		bpf_prog_put(prog->aux->dst_prog);
2809 	if (prog->aux->dst_trampoline && tr != prog->aux->dst_trampoline)
2810 		/* we allocated a new trampoline, so free the old one */
2811 		bpf_trampoline_put(prog->aux->dst_trampoline);
2812 
2813 	prog->aux->dst_prog = NULL;
2814 	prog->aux->dst_trampoline = NULL;
2815 	mutex_unlock(&prog->aux->dst_mutex);
2816 
2817 	return bpf_link_settle(&link_primer);
2818 out_unlock:
2819 	if (tr && tr != prog->aux->dst_trampoline)
2820 		bpf_trampoline_put(tr);
2821 	mutex_unlock(&prog->aux->dst_mutex);
2822 	kfree(link);
2823 out_put_prog:
2824 	if (tgt_prog_fd && tgt_prog)
2825 		bpf_prog_put(tgt_prog);
2826 	return err;
2827 }
2828 
2829 struct bpf_raw_tp_link {
2830 	struct bpf_link link;
2831 	struct bpf_raw_event_map *btp;
2832 };
2833 
2834 static void bpf_raw_tp_link_release(struct bpf_link *link)
2835 {
2836 	struct bpf_raw_tp_link *raw_tp =
2837 		container_of(link, struct bpf_raw_tp_link, link);
2838 
2839 	bpf_probe_unregister(raw_tp->btp, raw_tp->link.prog);
2840 	bpf_put_raw_tracepoint(raw_tp->btp);
2841 }
2842 
2843 static void bpf_raw_tp_link_dealloc(struct bpf_link *link)
2844 {
2845 	struct bpf_raw_tp_link *raw_tp =
2846 		container_of(link, struct bpf_raw_tp_link, link);
2847 
2848 	kfree(raw_tp);
2849 }
2850 
2851 static void bpf_raw_tp_link_show_fdinfo(const struct bpf_link *link,
2852 					struct seq_file *seq)
2853 {
2854 	struct bpf_raw_tp_link *raw_tp_link =
2855 		container_of(link, struct bpf_raw_tp_link, link);
2856 
2857 	seq_printf(seq,
2858 		   "tp_name:\t%s\n",
2859 		   raw_tp_link->btp->tp->name);
2860 }
2861 
2862 static int bpf_raw_tp_link_fill_link_info(const struct bpf_link *link,
2863 					  struct bpf_link_info *info)
2864 {
2865 	struct bpf_raw_tp_link *raw_tp_link =
2866 		container_of(link, struct bpf_raw_tp_link, link);
2867 	char __user *ubuf = u64_to_user_ptr(info->raw_tracepoint.tp_name);
2868 	const char *tp_name = raw_tp_link->btp->tp->name;
2869 	u32 ulen = info->raw_tracepoint.tp_name_len;
2870 	size_t tp_len = strlen(tp_name);
2871 
2872 	if (!ulen ^ !ubuf)
2873 		return -EINVAL;
2874 
2875 	info->raw_tracepoint.tp_name_len = tp_len + 1;
2876 
2877 	if (!ubuf)
2878 		return 0;
2879 
2880 	if (ulen >= tp_len + 1) {
2881 		if (copy_to_user(ubuf, tp_name, tp_len + 1))
2882 			return -EFAULT;
2883 	} else {
2884 		char zero = '\0';
2885 
2886 		if (copy_to_user(ubuf, tp_name, ulen - 1))
2887 			return -EFAULT;
2888 		if (put_user(zero, ubuf + ulen - 1))
2889 			return -EFAULT;
2890 		return -ENOSPC;
2891 	}
2892 
2893 	return 0;
2894 }
2895 
2896 static const struct bpf_link_ops bpf_raw_tp_link_lops = {
2897 	.release = bpf_raw_tp_link_release,
2898 	.dealloc = bpf_raw_tp_link_dealloc,
2899 	.show_fdinfo = bpf_raw_tp_link_show_fdinfo,
2900 	.fill_link_info = bpf_raw_tp_link_fill_link_info,
2901 };
2902 
2903 #ifdef CONFIG_PERF_EVENTS
2904 struct bpf_perf_link {
2905 	struct bpf_link link;
2906 	struct file *perf_file;
2907 };
2908 
2909 static void bpf_perf_link_release(struct bpf_link *link)
2910 {
2911 	struct bpf_perf_link *perf_link = container_of(link, struct bpf_perf_link, link);
2912 	struct perf_event *event = perf_link->perf_file->private_data;
2913 
2914 	perf_event_free_bpf_prog(event);
2915 	fput(perf_link->perf_file);
2916 }
2917 
2918 static void bpf_perf_link_dealloc(struct bpf_link *link)
2919 {
2920 	struct bpf_perf_link *perf_link = container_of(link, struct bpf_perf_link, link);
2921 
2922 	kfree(perf_link);
2923 }
2924 
2925 static const struct bpf_link_ops bpf_perf_link_lops = {
2926 	.release = bpf_perf_link_release,
2927 	.dealloc = bpf_perf_link_dealloc,
2928 };
2929 
2930 static int bpf_perf_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
2931 {
2932 	struct bpf_link_primer link_primer;
2933 	struct bpf_perf_link *link;
2934 	struct perf_event *event;
2935 	struct file *perf_file;
2936 	int err;
2937 
2938 	if (attr->link_create.flags)
2939 		return -EINVAL;
2940 
2941 	perf_file = perf_event_get(attr->link_create.target_fd);
2942 	if (IS_ERR(perf_file))
2943 		return PTR_ERR(perf_file);
2944 
2945 	link = kzalloc(sizeof(*link), GFP_USER);
2946 	if (!link) {
2947 		err = -ENOMEM;
2948 		goto out_put_file;
2949 	}
2950 	bpf_link_init(&link->link, BPF_LINK_TYPE_PERF_EVENT, &bpf_perf_link_lops, prog);
2951 	link->perf_file = perf_file;
2952 
2953 	err = bpf_link_prime(&link->link, &link_primer);
2954 	if (err) {
2955 		kfree(link);
2956 		goto out_put_file;
2957 	}
2958 
2959 	event = perf_file->private_data;
2960 	err = perf_event_set_bpf_prog(event, prog, attr->link_create.perf_event.bpf_cookie);
2961 	if (err) {
2962 		bpf_link_cleanup(&link_primer);
2963 		goto out_put_file;
2964 	}
2965 	/* perf_event_set_bpf_prog() doesn't take its own refcnt on prog */
2966 	bpf_prog_inc(prog);
2967 
2968 	return bpf_link_settle(&link_primer);
2969 
2970 out_put_file:
2971 	fput(perf_file);
2972 	return err;
2973 }
2974 #endif /* CONFIG_PERF_EVENTS */
2975 
2976 #define BPF_RAW_TRACEPOINT_OPEN_LAST_FIELD raw_tracepoint.prog_fd
2977 
2978 static int bpf_raw_tracepoint_open(const union bpf_attr *attr)
2979 {
2980 	struct bpf_link_primer link_primer;
2981 	struct bpf_raw_tp_link *link;
2982 	struct bpf_raw_event_map *btp;
2983 	struct bpf_prog *prog;
2984 	const char *tp_name;
2985 	char buf[128];
2986 	int err;
2987 
2988 	if (CHECK_ATTR(BPF_RAW_TRACEPOINT_OPEN))
2989 		return -EINVAL;
2990 
2991 	prog = bpf_prog_get(attr->raw_tracepoint.prog_fd);
2992 	if (IS_ERR(prog))
2993 		return PTR_ERR(prog);
2994 
2995 	switch (prog->type) {
2996 	case BPF_PROG_TYPE_TRACING:
2997 	case BPF_PROG_TYPE_EXT:
2998 	case BPF_PROG_TYPE_LSM:
2999 		if (attr->raw_tracepoint.name) {
3000 			/* The attach point for this category of programs
3001 			 * should be specified via btf_id during program load.
3002 			 */
3003 			err = -EINVAL;
3004 			goto out_put_prog;
3005 		}
3006 		if (prog->type == BPF_PROG_TYPE_TRACING &&
3007 		    prog->expected_attach_type == BPF_TRACE_RAW_TP) {
3008 			tp_name = prog->aux->attach_func_name;
3009 			break;
3010 		}
3011 		err = bpf_tracing_prog_attach(prog, 0, 0);
3012 		if (err >= 0)
3013 			return err;
3014 		goto out_put_prog;
3015 	case BPF_PROG_TYPE_RAW_TRACEPOINT:
3016 	case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE:
3017 		if (strncpy_from_user(buf,
3018 				      u64_to_user_ptr(attr->raw_tracepoint.name),
3019 				      sizeof(buf) - 1) < 0) {
3020 			err = -EFAULT;
3021 			goto out_put_prog;
3022 		}
3023 		buf[sizeof(buf) - 1] = 0;
3024 		tp_name = buf;
3025 		break;
3026 	default:
3027 		err = -EINVAL;
3028 		goto out_put_prog;
3029 	}
3030 
3031 	btp = bpf_get_raw_tracepoint(tp_name);
3032 	if (!btp) {
3033 		err = -ENOENT;
3034 		goto out_put_prog;
3035 	}
3036 
3037 	link = kzalloc(sizeof(*link), GFP_USER);
3038 	if (!link) {
3039 		err = -ENOMEM;
3040 		goto out_put_btp;
3041 	}
3042 	bpf_link_init(&link->link, BPF_LINK_TYPE_RAW_TRACEPOINT,
3043 		      &bpf_raw_tp_link_lops, prog);
3044 	link->btp = btp;
3045 
3046 	err = bpf_link_prime(&link->link, &link_primer);
3047 	if (err) {
3048 		kfree(link);
3049 		goto out_put_btp;
3050 	}
3051 
3052 	err = bpf_probe_register(link->btp, prog);
3053 	if (err) {
3054 		bpf_link_cleanup(&link_primer);
3055 		goto out_put_btp;
3056 	}
3057 
3058 	return bpf_link_settle(&link_primer);
3059 
3060 out_put_btp:
3061 	bpf_put_raw_tracepoint(btp);
3062 out_put_prog:
3063 	bpf_prog_put(prog);
3064 	return err;
3065 }
3066 
3067 static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog,
3068 					     enum bpf_attach_type attach_type)
3069 {
3070 	switch (prog->type) {
3071 	case BPF_PROG_TYPE_CGROUP_SOCK:
3072 	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
3073 	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
3074 	case BPF_PROG_TYPE_SK_LOOKUP:
3075 		return attach_type == prog->expected_attach_type ? 0 : -EINVAL;
3076 	case BPF_PROG_TYPE_CGROUP_SKB:
3077 		if (!capable(CAP_NET_ADMIN))
3078 			/* cg-skb progs can be loaded by unpriv user.
3079 			 * check permissions at attach time.
3080 			 */
3081 			return -EPERM;
3082 		return prog->enforce_expected_attach_type &&
3083 			prog->expected_attach_type != attach_type ?
3084 			-EINVAL : 0;
3085 	default:
3086 		return 0;
3087 	}
3088 }
3089 
3090 static enum bpf_prog_type
3091 attach_type_to_prog_type(enum bpf_attach_type attach_type)
3092 {
3093 	switch (attach_type) {
3094 	case BPF_CGROUP_INET_INGRESS:
3095 	case BPF_CGROUP_INET_EGRESS:
3096 		return BPF_PROG_TYPE_CGROUP_SKB;
3097 	case BPF_CGROUP_INET_SOCK_CREATE:
3098 	case BPF_CGROUP_INET_SOCK_RELEASE:
3099 	case BPF_CGROUP_INET4_POST_BIND:
3100 	case BPF_CGROUP_INET6_POST_BIND:
3101 		return BPF_PROG_TYPE_CGROUP_SOCK;
3102 	case BPF_CGROUP_INET4_BIND:
3103 	case BPF_CGROUP_INET6_BIND:
3104 	case BPF_CGROUP_INET4_CONNECT:
3105 	case BPF_CGROUP_INET6_CONNECT:
3106 	case BPF_CGROUP_INET4_GETPEERNAME:
3107 	case BPF_CGROUP_INET6_GETPEERNAME:
3108 	case BPF_CGROUP_INET4_GETSOCKNAME:
3109 	case BPF_CGROUP_INET6_GETSOCKNAME:
3110 	case BPF_CGROUP_UDP4_SENDMSG:
3111 	case BPF_CGROUP_UDP6_SENDMSG:
3112 	case BPF_CGROUP_UDP4_RECVMSG:
3113 	case BPF_CGROUP_UDP6_RECVMSG:
3114 		return BPF_PROG_TYPE_CGROUP_SOCK_ADDR;
3115 	case BPF_CGROUP_SOCK_OPS:
3116 		return BPF_PROG_TYPE_SOCK_OPS;
3117 	case BPF_CGROUP_DEVICE:
3118 		return BPF_PROG_TYPE_CGROUP_DEVICE;
3119 	case BPF_SK_MSG_VERDICT:
3120 		return BPF_PROG_TYPE_SK_MSG;
3121 	case BPF_SK_SKB_STREAM_PARSER:
3122 	case BPF_SK_SKB_STREAM_VERDICT:
3123 	case BPF_SK_SKB_VERDICT:
3124 		return BPF_PROG_TYPE_SK_SKB;
3125 	case BPF_LIRC_MODE2:
3126 		return BPF_PROG_TYPE_LIRC_MODE2;
3127 	case BPF_FLOW_DISSECTOR:
3128 		return BPF_PROG_TYPE_FLOW_DISSECTOR;
3129 	case BPF_CGROUP_SYSCTL:
3130 		return BPF_PROG_TYPE_CGROUP_SYSCTL;
3131 	case BPF_CGROUP_GETSOCKOPT:
3132 	case BPF_CGROUP_SETSOCKOPT:
3133 		return BPF_PROG_TYPE_CGROUP_SOCKOPT;
3134 	case BPF_TRACE_ITER:
3135 		return BPF_PROG_TYPE_TRACING;
3136 	case BPF_SK_LOOKUP:
3137 		return BPF_PROG_TYPE_SK_LOOKUP;
3138 	case BPF_XDP:
3139 		return BPF_PROG_TYPE_XDP;
3140 	default:
3141 		return BPF_PROG_TYPE_UNSPEC;
3142 	}
3143 }
3144 
3145 #define BPF_PROG_ATTACH_LAST_FIELD replace_bpf_fd
3146 
3147 #define BPF_F_ATTACH_MASK \
3148 	(BPF_F_ALLOW_OVERRIDE | BPF_F_ALLOW_MULTI | BPF_F_REPLACE)
3149 
3150 static int bpf_prog_attach(const union bpf_attr *attr)
3151 {
3152 	enum bpf_prog_type ptype;
3153 	struct bpf_prog *prog;
3154 	int ret;
3155 
3156 	if (CHECK_ATTR(BPF_PROG_ATTACH))
3157 		return -EINVAL;
3158 
3159 	if (attr->attach_flags & ~BPF_F_ATTACH_MASK)
3160 		return -EINVAL;
3161 
3162 	ptype = attach_type_to_prog_type(attr->attach_type);
3163 	if (ptype == BPF_PROG_TYPE_UNSPEC)
3164 		return -EINVAL;
3165 
3166 	prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype);
3167 	if (IS_ERR(prog))
3168 		return PTR_ERR(prog);
3169 
3170 	if (bpf_prog_attach_check_attach_type(prog, attr->attach_type)) {
3171 		bpf_prog_put(prog);
3172 		return -EINVAL;
3173 	}
3174 
3175 	switch (ptype) {
3176 	case BPF_PROG_TYPE_SK_SKB:
3177 	case BPF_PROG_TYPE_SK_MSG:
3178 		ret = sock_map_get_from_fd(attr, prog);
3179 		break;
3180 	case BPF_PROG_TYPE_LIRC_MODE2:
3181 		ret = lirc_prog_attach(attr, prog);
3182 		break;
3183 	case BPF_PROG_TYPE_FLOW_DISSECTOR:
3184 		ret = netns_bpf_prog_attach(attr, prog);
3185 		break;
3186 	case BPF_PROG_TYPE_CGROUP_DEVICE:
3187 	case BPF_PROG_TYPE_CGROUP_SKB:
3188 	case BPF_PROG_TYPE_CGROUP_SOCK:
3189 	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
3190 	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
3191 	case BPF_PROG_TYPE_CGROUP_SYSCTL:
3192 	case BPF_PROG_TYPE_SOCK_OPS:
3193 		ret = cgroup_bpf_prog_attach(attr, ptype, prog);
3194 		break;
3195 	default:
3196 		ret = -EINVAL;
3197 	}
3198 
3199 	if (ret)
3200 		bpf_prog_put(prog);
3201 	return ret;
3202 }
3203 
3204 #define BPF_PROG_DETACH_LAST_FIELD attach_type
3205 
3206 static int bpf_prog_detach(const union bpf_attr *attr)
3207 {
3208 	enum bpf_prog_type ptype;
3209 
3210 	if (CHECK_ATTR(BPF_PROG_DETACH))
3211 		return -EINVAL;
3212 
3213 	ptype = attach_type_to_prog_type(attr->attach_type);
3214 
3215 	switch (ptype) {
3216 	case BPF_PROG_TYPE_SK_MSG:
3217 	case BPF_PROG_TYPE_SK_SKB:
3218 		return sock_map_prog_detach(attr, ptype);
3219 	case BPF_PROG_TYPE_LIRC_MODE2:
3220 		return lirc_prog_detach(attr);
3221 	case BPF_PROG_TYPE_FLOW_DISSECTOR:
3222 		return netns_bpf_prog_detach(attr, ptype);
3223 	case BPF_PROG_TYPE_CGROUP_DEVICE:
3224 	case BPF_PROG_TYPE_CGROUP_SKB:
3225 	case BPF_PROG_TYPE_CGROUP_SOCK:
3226 	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
3227 	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
3228 	case BPF_PROG_TYPE_CGROUP_SYSCTL:
3229 	case BPF_PROG_TYPE_SOCK_OPS:
3230 		return cgroup_bpf_prog_detach(attr, ptype);
3231 	default:
3232 		return -EINVAL;
3233 	}
3234 }
3235 
3236 #define BPF_PROG_QUERY_LAST_FIELD query.prog_cnt
3237 
3238 static int bpf_prog_query(const union bpf_attr *attr,
3239 			  union bpf_attr __user *uattr)
3240 {
3241 	if (!capable(CAP_NET_ADMIN))
3242 		return -EPERM;
3243 	if (CHECK_ATTR(BPF_PROG_QUERY))
3244 		return -EINVAL;
3245 	if (attr->query.query_flags & ~BPF_F_QUERY_EFFECTIVE)
3246 		return -EINVAL;
3247 
3248 	switch (attr->query.attach_type) {
3249 	case BPF_CGROUP_INET_INGRESS:
3250 	case BPF_CGROUP_INET_EGRESS:
3251 	case BPF_CGROUP_INET_SOCK_CREATE:
3252 	case BPF_CGROUP_INET_SOCK_RELEASE:
3253 	case BPF_CGROUP_INET4_BIND:
3254 	case BPF_CGROUP_INET6_BIND:
3255 	case BPF_CGROUP_INET4_POST_BIND:
3256 	case BPF_CGROUP_INET6_POST_BIND:
3257 	case BPF_CGROUP_INET4_CONNECT:
3258 	case BPF_CGROUP_INET6_CONNECT:
3259 	case BPF_CGROUP_INET4_GETPEERNAME:
3260 	case BPF_CGROUP_INET6_GETPEERNAME:
3261 	case BPF_CGROUP_INET4_GETSOCKNAME:
3262 	case BPF_CGROUP_INET6_GETSOCKNAME:
3263 	case BPF_CGROUP_UDP4_SENDMSG:
3264 	case BPF_CGROUP_UDP6_SENDMSG:
3265 	case BPF_CGROUP_UDP4_RECVMSG:
3266 	case BPF_CGROUP_UDP6_RECVMSG:
3267 	case BPF_CGROUP_SOCK_OPS:
3268 	case BPF_CGROUP_DEVICE:
3269 	case BPF_CGROUP_SYSCTL:
3270 	case BPF_CGROUP_GETSOCKOPT:
3271 	case BPF_CGROUP_SETSOCKOPT:
3272 		return cgroup_bpf_prog_query(attr, uattr);
3273 	case BPF_LIRC_MODE2:
3274 		return lirc_prog_query(attr, uattr);
3275 	case BPF_FLOW_DISSECTOR:
3276 	case BPF_SK_LOOKUP:
3277 		return netns_bpf_prog_query(attr, uattr);
3278 	default:
3279 		return -EINVAL;
3280 	}
3281 }
3282 
3283 #define BPF_PROG_TEST_RUN_LAST_FIELD test.cpu
3284 
3285 static int bpf_prog_test_run(const union bpf_attr *attr,
3286 			     union bpf_attr __user *uattr)
3287 {
3288 	struct bpf_prog *prog;
3289 	int ret = -ENOTSUPP;
3290 
3291 	if (CHECK_ATTR(BPF_PROG_TEST_RUN))
3292 		return -EINVAL;
3293 
3294 	if ((attr->test.ctx_size_in && !attr->test.ctx_in) ||
3295 	    (!attr->test.ctx_size_in && attr->test.ctx_in))
3296 		return -EINVAL;
3297 
3298 	if ((attr->test.ctx_size_out && !attr->test.ctx_out) ||
3299 	    (!attr->test.ctx_size_out && attr->test.ctx_out))
3300 		return -EINVAL;
3301 
3302 	prog = bpf_prog_get(attr->test.prog_fd);
3303 	if (IS_ERR(prog))
3304 		return PTR_ERR(prog);
3305 
3306 	if (prog->aux->ops->test_run)
3307 		ret = prog->aux->ops->test_run(prog, attr, uattr);
3308 
3309 	bpf_prog_put(prog);
3310 	return ret;
3311 }
3312 
3313 #define BPF_OBJ_GET_NEXT_ID_LAST_FIELD next_id
3314 
3315 static int bpf_obj_get_next_id(const union bpf_attr *attr,
3316 			       union bpf_attr __user *uattr,
3317 			       struct idr *idr,
3318 			       spinlock_t *lock)
3319 {
3320 	u32 next_id = attr->start_id;
3321 	int err = 0;
3322 
3323 	if (CHECK_ATTR(BPF_OBJ_GET_NEXT_ID) || next_id >= INT_MAX)
3324 		return -EINVAL;
3325 
3326 	if (!capable(CAP_SYS_ADMIN))
3327 		return -EPERM;
3328 
3329 	next_id++;
3330 	spin_lock_bh(lock);
3331 	if (!idr_get_next(idr, &next_id))
3332 		err = -ENOENT;
3333 	spin_unlock_bh(lock);
3334 
3335 	if (!err)
3336 		err = put_user(next_id, &uattr->next_id);
3337 
3338 	return err;
3339 }
3340 
3341 struct bpf_map *bpf_map_get_curr_or_next(u32 *id)
3342 {
3343 	struct bpf_map *map;
3344 
3345 	spin_lock_bh(&map_idr_lock);
3346 again:
3347 	map = idr_get_next(&map_idr, id);
3348 	if (map) {
3349 		map = __bpf_map_inc_not_zero(map, false);
3350 		if (IS_ERR(map)) {
3351 			(*id)++;
3352 			goto again;
3353 		}
3354 	}
3355 	spin_unlock_bh(&map_idr_lock);
3356 
3357 	return map;
3358 }
3359 
3360 struct bpf_prog *bpf_prog_get_curr_or_next(u32 *id)
3361 {
3362 	struct bpf_prog *prog;
3363 
3364 	spin_lock_bh(&prog_idr_lock);
3365 again:
3366 	prog = idr_get_next(&prog_idr, id);
3367 	if (prog) {
3368 		prog = bpf_prog_inc_not_zero(prog);
3369 		if (IS_ERR(prog)) {
3370 			(*id)++;
3371 			goto again;
3372 		}
3373 	}
3374 	spin_unlock_bh(&prog_idr_lock);
3375 
3376 	return prog;
3377 }
3378 
3379 #define BPF_PROG_GET_FD_BY_ID_LAST_FIELD prog_id
3380 
3381 struct bpf_prog *bpf_prog_by_id(u32 id)
3382 {
3383 	struct bpf_prog *prog;
3384 
3385 	if (!id)
3386 		return ERR_PTR(-ENOENT);
3387 
3388 	spin_lock_bh(&prog_idr_lock);
3389 	prog = idr_find(&prog_idr, id);
3390 	if (prog)
3391 		prog = bpf_prog_inc_not_zero(prog);
3392 	else
3393 		prog = ERR_PTR(-ENOENT);
3394 	spin_unlock_bh(&prog_idr_lock);
3395 	return prog;
3396 }
3397 
3398 static int bpf_prog_get_fd_by_id(const union bpf_attr *attr)
3399 {
3400 	struct bpf_prog *prog;
3401 	u32 id = attr->prog_id;
3402 	int fd;
3403 
3404 	if (CHECK_ATTR(BPF_PROG_GET_FD_BY_ID))
3405 		return -EINVAL;
3406 
3407 	if (!capable(CAP_SYS_ADMIN))
3408 		return -EPERM;
3409 
3410 	prog = bpf_prog_by_id(id);
3411 	if (IS_ERR(prog))
3412 		return PTR_ERR(prog);
3413 
3414 	fd = bpf_prog_new_fd(prog);
3415 	if (fd < 0)
3416 		bpf_prog_put(prog);
3417 
3418 	return fd;
3419 }
3420 
3421 #define BPF_MAP_GET_FD_BY_ID_LAST_FIELD open_flags
3422 
3423 static int bpf_map_get_fd_by_id(const union bpf_attr *attr)
3424 {
3425 	struct bpf_map *map;
3426 	u32 id = attr->map_id;
3427 	int f_flags;
3428 	int fd;
3429 
3430 	if (CHECK_ATTR(BPF_MAP_GET_FD_BY_ID) ||
3431 	    attr->open_flags & ~BPF_OBJ_FLAG_MASK)
3432 		return -EINVAL;
3433 
3434 	if (!capable(CAP_SYS_ADMIN))
3435 		return -EPERM;
3436 
3437 	f_flags = bpf_get_file_flag(attr->open_flags);
3438 	if (f_flags < 0)
3439 		return f_flags;
3440 
3441 	spin_lock_bh(&map_idr_lock);
3442 	map = idr_find(&map_idr, id);
3443 	if (map)
3444 		map = __bpf_map_inc_not_zero(map, true);
3445 	else
3446 		map = ERR_PTR(-ENOENT);
3447 	spin_unlock_bh(&map_idr_lock);
3448 
3449 	if (IS_ERR(map))
3450 		return PTR_ERR(map);
3451 
3452 	fd = bpf_map_new_fd(map, f_flags);
3453 	if (fd < 0)
3454 		bpf_map_put_with_uref(map);
3455 
3456 	return fd;
3457 }
3458 
3459 static const struct bpf_map *bpf_map_from_imm(const struct bpf_prog *prog,
3460 					      unsigned long addr, u32 *off,
3461 					      u32 *type)
3462 {
3463 	const struct bpf_map *map;
3464 	int i;
3465 
3466 	mutex_lock(&prog->aux->used_maps_mutex);
3467 	for (i = 0, *off = 0; i < prog->aux->used_map_cnt; i++) {
3468 		map = prog->aux->used_maps[i];
3469 		if (map == (void *)addr) {
3470 			*type = BPF_PSEUDO_MAP_FD;
3471 			goto out;
3472 		}
3473 		if (!map->ops->map_direct_value_meta)
3474 			continue;
3475 		if (!map->ops->map_direct_value_meta(map, addr, off)) {
3476 			*type = BPF_PSEUDO_MAP_VALUE;
3477 			goto out;
3478 		}
3479 	}
3480 	map = NULL;
3481 
3482 out:
3483 	mutex_unlock(&prog->aux->used_maps_mutex);
3484 	return map;
3485 }
3486 
3487 static struct bpf_insn *bpf_insn_prepare_dump(const struct bpf_prog *prog,
3488 					      const struct cred *f_cred)
3489 {
3490 	const struct bpf_map *map;
3491 	struct bpf_insn *insns;
3492 	u32 off, type;
3493 	u64 imm;
3494 	u8 code;
3495 	int i;
3496 
3497 	insns = kmemdup(prog->insnsi, bpf_prog_insn_size(prog),
3498 			GFP_USER);
3499 	if (!insns)
3500 		return insns;
3501 
3502 	for (i = 0; i < prog->len; i++) {
3503 		code = insns[i].code;
3504 
3505 		if (code == (BPF_JMP | BPF_TAIL_CALL)) {
3506 			insns[i].code = BPF_JMP | BPF_CALL;
3507 			insns[i].imm = BPF_FUNC_tail_call;
3508 			/* fall-through */
3509 		}
3510 		if (code == (BPF_JMP | BPF_CALL) ||
3511 		    code == (BPF_JMP | BPF_CALL_ARGS)) {
3512 			if (code == (BPF_JMP | BPF_CALL_ARGS))
3513 				insns[i].code = BPF_JMP | BPF_CALL;
3514 			if (!bpf_dump_raw_ok(f_cred))
3515 				insns[i].imm = 0;
3516 			continue;
3517 		}
3518 		if (BPF_CLASS(code) == BPF_LDX && BPF_MODE(code) == BPF_PROBE_MEM) {
3519 			insns[i].code = BPF_LDX | BPF_SIZE(code) | BPF_MEM;
3520 			continue;
3521 		}
3522 
3523 		if (code != (BPF_LD | BPF_IMM | BPF_DW))
3524 			continue;
3525 
3526 		imm = ((u64)insns[i + 1].imm << 32) | (u32)insns[i].imm;
3527 		map = bpf_map_from_imm(prog, imm, &off, &type);
3528 		if (map) {
3529 			insns[i].src_reg = type;
3530 			insns[i].imm = map->id;
3531 			insns[i + 1].imm = off;
3532 			continue;
3533 		}
3534 	}
3535 
3536 	return insns;
3537 }
3538 
3539 static int set_info_rec_size(struct bpf_prog_info *info)
3540 {
3541 	/*
3542 	 * Ensure info.*_rec_size is the same as kernel expected size
3543 	 *
3544 	 * or
3545 	 *
3546 	 * Only allow zero *_rec_size if both _rec_size and _cnt are
3547 	 * zero.  In this case, the kernel will set the expected
3548 	 * _rec_size back to the info.
3549 	 */
3550 
3551 	if ((info->nr_func_info || info->func_info_rec_size) &&
3552 	    info->func_info_rec_size != sizeof(struct bpf_func_info))
3553 		return -EINVAL;
3554 
3555 	if ((info->nr_line_info || info->line_info_rec_size) &&
3556 	    info->line_info_rec_size != sizeof(struct bpf_line_info))
3557 		return -EINVAL;
3558 
3559 	if ((info->nr_jited_line_info || info->jited_line_info_rec_size) &&
3560 	    info->jited_line_info_rec_size != sizeof(__u64))
3561 		return -EINVAL;
3562 
3563 	info->func_info_rec_size = sizeof(struct bpf_func_info);
3564 	info->line_info_rec_size = sizeof(struct bpf_line_info);
3565 	info->jited_line_info_rec_size = sizeof(__u64);
3566 
3567 	return 0;
3568 }
3569 
3570 static int bpf_prog_get_info_by_fd(struct file *file,
3571 				   struct bpf_prog *prog,
3572 				   const union bpf_attr *attr,
3573 				   union bpf_attr __user *uattr)
3574 {
3575 	struct bpf_prog_info __user *uinfo = u64_to_user_ptr(attr->info.info);
3576 	struct bpf_prog_info info;
3577 	u32 info_len = attr->info.info_len;
3578 	struct bpf_prog_stats stats;
3579 	char __user *uinsns;
3580 	u32 ulen;
3581 	int err;
3582 
3583 	err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len);
3584 	if (err)
3585 		return err;
3586 	info_len = min_t(u32, sizeof(info), info_len);
3587 
3588 	memset(&info, 0, sizeof(info));
3589 	if (copy_from_user(&info, uinfo, info_len))
3590 		return -EFAULT;
3591 
3592 	info.type = prog->type;
3593 	info.id = prog->aux->id;
3594 	info.load_time = prog->aux->load_time;
3595 	info.created_by_uid = from_kuid_munged(current_user_ns(),
3596 					       prog->aux->user->uid);
3597 	info.gpl_compatible = prog->gpl_compatible;
3598 
3599 	memcpy(info.tag, prog->tag, sizeof(prog->tag));
3600 	memcpy(info.name, prog->aux->name, sizeof(prog->aux->name));
3601 
3602 	mutex_lock(&prog->aux->used_maps_mutex);
3603 	ulen = info.nr_map_ids;
3604 	info.nr_map_ids = prog->aux->used_map_cnt;
3605 	ulen = min_t(u32, info.nr_map_ids, ulen);
3606 	if (ulen) {
3607 		u32 __user *user_map_ids = u64_to_user_ptr(info.map_ids);
3608 		u32 i;
3609 
3610 		for (i = 0; i < ulen; i++)
3611 			if (put_user(prog->aux->used_maps[i]->id,
3612 				     &user_map_ids[i])) {
3613 				mutex_unlock(&prog->aux->used_maps_mutex);
3614 				return -EFAULT;
3615 			}
3616 	}
3617 	mutex_unlock(&prog->aux->used_maps_mutex);
3618 
3619 	err = set_info_rec_size(&info);
3620 	if (err)
3621 		return err;
3622 
3623 	bpf_prog_get_stats(prog, &stats);
3624 	info.run_time_ns = stats.nsecs;
3625 	info.run_cnt = stats.cnt;
3626 	info.recursion_misses = stats.misses;
3627 
3628 	if (!bpf_capable()) {
3629 		info.jited_prog_len = 0;
3630 		info.xlated_prog_len = 0;
3631 		info.nr_jited_ksyms = 0;
3632 		info.nr_jited_func_lens = 0;
3633 		info.nr_func_info = 0;
3634 		info.nr_line_info = 0;
3635 		info.nr_jited_line_info = 0;
3636 		goto done;
3637 	}
3638 
3639 	ulen = info.xlated_prog_len;
3640 	info.xlated_prog_len = bpf_prog_insn_size(prog);
3641 	if (info.xlated_prog_len && ulen) {
3642 		struct bpf_insn *insns_sanitized;
3643 		bool fault;
3644 
3645 		if (prog->blinded && !bpf_dump_raw_ok(file->f_cred)) {
3646 			info.xlated_prog_insns = 0;
3647 			goto done;
3648 		}
3649 		insns_sanitized = bpf_insn_prepare_dump(prog, file->f_cred);
3650 		if (!insns_sanitized)
3651 			return -ENOMEM;
3652 		uinsns = u64_to_user_ptr(info.xlated_prog_insns);
3653 		ulen = min_t(u32, info.xlated_prog_len, ulen);
3654 		fault = copy_to_user(uinsns, insns_sanitized, ulen);
3655 		kfree(insns_sanitized);
3656 		if (fault)
3657 			return -EFAULT;
3658 	}
3659 
3660 	if (bpf_prog_is_dev_bound(prog->aux)) {
3661 		err = bpf_prog_offload_info_fill(&info, prog);
3662 		if (err)
3663 			return err;
3664 		goto done;
3665 	}
3666 
3667 	/* NOTE: the following code is supposed to be skipped for offload.
3668 	 * bpf_prog_offload_info_fill() is the place to fill similar fields
3669 	 * for offload.
3670 	 */
3671 	ulen = info.jited_prog_len;
3672 	if (prog->aux->func_cnt) {
3673 		u32 i;
3674 
3675 		info.jited_prog_len = 0;
3676 		for (i = 0; i < prog->aux->func_cnt; i++)
3677 			info.jited_prog_len += prog->aux->func[i]->jited_len;
3678 	} else {
3679 		info.jited_prog_len = prog->jited_len;
3680 	}
3681 
3682 	if (info.jited_prog_len && ulen) {
3683 		if (bpf_dump_raw_ok(file->f_cred)) {
3684 			uinsns = u64_to_user_ptr(info.jited_prog_insns);
3685 			ulen = min_t(u32, info.jited_prog_len, ulen);
3686 
3687 			/* for multi-function programs, copy the JITed
3688 			 * instructions for all the functions
3689 			 */
3690 			if (prog->aux->func_cnt) {
3691 				u32 len, free, i;
3692 				u8 *img;
3693 
3694 				free = ulen;
3695 				for (i = 0; i < prog->aux->func_cnt; i++) {
3696 					len = prog->aux->func[i]->jited_len;
3697 					len = min_t(u32, len, free);
3698 					img = (u8 *) prog->aux->func[i]->bpf_func;
3699 					if (copy_to_user(uinsns, img, len))
3700 						return -EFAULT;
3701 					uinsns += len;
3702 					free -= len;
3703 					if (!free)
3704 						break;
3705 				}
3706 			} else {
3707 				if (copy_to_user(uinsns, prog->bpf_func, ulen))
3708 					return -EFAULT;
3709 			}
3710 		} else {
3711 			info.jited_prog_insns = 0;
3712 		}
3713 	}
3714 
3715 	ulen = info.nr_jited_ksyms;
3716 	info.nr_jited_ksyms = prog->aux->func_cnt ? : 1;
3717 	if (ulen) {
3718 		if (bpf_dump_raw_ok(file->f_cred)) {
3719 			unsigned long ksym_addr;
3720 			u64 __user *user_ksyms;
3721 			u32 i;
3722 
3723 			/* copy the address of the kernel symbol
3724 			 * corresponding to each function
3725 			 */
3726 			ulen = min_t(u32, info.nr_jited_ksyms, ulen);
3727 			user_ksyms = u64_to_user_ptr(info.jited_ksyms);
3728 			if (prog->aux->func_cnt) {
3729 				for (i = 0; i < ulen; i++) {
3730 					ksym_addr = (unsigned long)
3731 						prog->aux->func[i]->bpf_func;
3732 					if (put_user((u64) ksym_addr,
3733 						     &user_ksyms[i]))
3734 						return -EFAULT;
3735 				}
3736 			} else {
3737 				ksym_addr = (unsigned long) prog->bpf_func;
3738 				if (put_user((u64) ksym_addr, &user_ksyms[0]))
3739 					return -EFAULT;
3740 			}
3741 		} else {
3742 			info.jited_ksyms = 0;
3743 		}
3744 	}
3745 
3746 	ulen = info.nr_jited_func_lens;
3747 	info.nr_jited_func_lens = prog->aux->func_cnt ? : 1;
3748 	if (ulen) {
3749 		if (bpf_dump_raw_ok(file->f_cred)) {
3750 			u32 __user *user_lens;
3751 			u32 func_len, i;
3752 
3753 			/* copy the JITed image lengths for each function */
3754 			ulen = min_t(u32, info.nr_jited_func_lens, ulen);
3755 			user_lens = u64_to_user_ptr(info.jited_func_lens);
3756 			if (prog->aux->func_cnt) {
3757 				for (i = 0; i < ulen; i++) {
3758 					func_len =
3759 						prog->aux->func[i]->jited_len;
3760 					if (put_user(func_len, &user_lens[i]))
3761 						return -EFAULT;
3762 				}
3763 			} else {
3764 				func_len = prog->jited_len;
3765 				if (put_user(func_len, &user_lens[0]))
3766 					return -EFAULT;
3767 			}
3768 		} else {
3769 			info.jited_func_lens = 0;
3770 		}
3771 	}
3772 
3773 	if (prog->aux->btf)
3774 		info.btf_id = btf_obj_id(prog->aux->btf);
3775 
3776 	ulen = info.nr_func_info;
3777 	info.nr_func_info = prog->aux->func_info_cnt;
3778 	if (info.nr_func_info && ulen) {
3779 		char __user *user_finfo;
3780 
3781 		user_finfo = u64_to_user_ptr(info.func_info);
3782 		ulen = min_t(u32, info.nr_func_info, ulen);
3783 		if (copy_to_user(user_finfo, prog->aux->func_info,
3784 				 info.func_info_rec_size * ulen))
3785 			return -EFAULT;
3786 	}
3787 
3788 	ulen = info.nr_line_info;
3789 	info.nr_line_info = prog->aux->nr_linfo;
3790 	if (info.nr_line_info && ulen) {
3791 		__u8 __user *user_linfo;
3792 
3793 		user_linfo = u64_to_user_ptr(info.line_info);
3794 		ulen = min_t(u32, info.nr_line_info, ulen);
3795 		if (copy_to_user(user_linfo, prog->aux->linfo,
3796 				 info.line_info_rec_size * ulen))
3797 			return -EFAULT;
3798 	}
3799 
3800 	ulen = info.nr_jited_line_info;
3801 	if (prog->aux->jited_linfo)
3802 		info.nr_jited_line_info = prog->aux->nr_linfo;
3803 	else
3804 		info.nr_jited_line_info = 0;
3805 	if (info.nr_jited_line_info && ulen) {
3806 		if (bpf_dump_raw_ok(file->f_cred)) {
3807 			__u64 __user *user_linfo;
3808 			u32 i;
3809 
3810 			user_linfo = u64_to_user_ptr(info.jited_line_info);
3811 			ulen = min_t(u32, info.nr_jited_line_info, ulen);
3812 			for (i = 0; i < ulen; i++) {
3813 				if (put_user((__u64)(long)prog->aux->jited_linfo[i],
3814 					     &user_linfo[i]))
3815 					return -EFAULT;
3816 			}
3817 		} else {
3818 			info.jited_line_info = 0;
3819 		}
3820 	}
3821 
3822 	ulen = info.nr_prog_tags;
3823 	info.nr_prog_tags = prog->aux->func_cnt ? : 1;
3824 	if (ulen) {
3825 		__u8 __user (*user_prog_tags)[BPF_TAG_SIZE];
3826 		u32 i;
3827 
3828 		user_prog_tags = u64_to_user_ptr(info.prog_tags);
3829 		ulen = min_t(u32, info.nr_prog_tags, ulen);
3830 		if (prog->aux->func_cnt) {
3831 			for (i = 0; i < ulen; i++) {
3832 				if (copy_to_user(user_prog_tags[i],
3833 						 prog->aux->func[i]->tag,
3834 						 BPF_TAG_SIZE))
3835 					return -EFAULT;
3836 			}
3837 		} else {
3838 			if (copy_to_user(user_prog_tags[0],
3839 					 prog->tag, BPF_TAG_SIZE))
3840 				return -EFAULT;
3841 		}
3842 	}
3843 
3844 done:
3845 	if (copy_to_user(uinfo, &info, info_len) ||
3846 	    put_user(info_len, &uattr->info.info_len))
3847 		return -EFAULT;
3848 
3849 	return 0;
3850 }
3851 
3852 static int bpf_map_get_info_by_fd(struct file *file,
3853 				  struct bpf_map *map,
3854 				  const union bpf_attr *attr,
3855 				  union bpf_attr __user *uattr)
3856 {
3857 	struct bpf_map_info __user *uinfo = u64_to_user_ptr(attr->info.info);
3858 	struct bpf_map_info info;
3859 	u32 info_len = attr->info.info_len;
3860 	int err;
3861 
3862 	err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len);
3863 	if (err)
3864 		return err;
3865 	info_len = min_t(u32, sizeof(info), info_len);
3866 
3867 	memset(&info, 0, sizeof(info));
3868 	info.type = map->map_type;
3869 	info.id = map->id;
3870 	info.key_size = map->key_size;
3871 	info.value_size = map->value_size;
3872 	info.max_entries = map->max_entries;
3873 	info.map_flags = map->map_flags;
3874 	memcpy(info.name, map->name, sizeof(map->name));
3875 
3876 	if (map->btf) {
3877 		info.btf_id = btf_obj_id(map->btf);
3878 		info.btf_key_type_id = map->btf_key_type_id;
3879 		info.btf_value_type_id = map->btf_value_type_id;
3880 	}
3881 	info.btf_vmlinux_value_type_id = map->btf_vmlinux_value_type_id;
3882 
3883 	if (bpf_map_is_dev_bound(map)) {
3884 		err = bpf_map_offload_info_fill(&info, map);
3885 		if (err)
3886 			return err;
3887 	}
3888 
3889 	if (copy_to_user(uinfo, &info, info_len) ||
3890 	    put_user(info_len, &uattr->info.info_len))
3891 		return -EFAULT;
3892 
3893 	return 0;
3894 }
3895 
3896 static int bpf_btf_get_info_by_fd(struct file *file,
3897 				  struct btf *btf,
3898 				  const union bpf_attr *attr,
3899 				  union bpf_attr __user *uattr)
3900 {
3901 	struct bpf_btf_info __user *uinfo = u64_to_user_ptr(attr->info.info);
3902 	u32 info_len = attr->info.info_len;
3903 	int err;
3904 
3905 	err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(*uinfo), info_len);
3906 	if (err)
3907 		return err;
3908 
3909 	return btf_get_info_by_fd(btf, attr, uattr);
3910 }
3911 
3912 static int bpf_link_get_info_by_fd(struct file *file,
3913 				  struct bpf_link *link,
3914 				  const union bpf_attr *attr,
3915 				  union bpf_attr __user *uattr)
3916 {
3917 	struct bpf_link_info __user *uinfo = u64_to_user_ptr(attr->info.info);
3918 	struct bpf_link_info info;
3919 	u32 info_len = attr->info.info_len;
3920 	int err;
3921 
3922 	err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len);
3923 	if (err)
3924 		return err;
3925 	info_len = min_t(u32, sizeof(info), info_len);
3926 
3927 	memset(&info, 0, sizeof(info));
3928 	if (copy_from_user(&info, uinfo, info_len))
3929 		return -EFAULT;
3930 
3931 	info.type = link->type;
3932 	info.id = link->id;
3933 	info.prog_id = link->prog->aux->id;
3934 
3935 	if (link->ops->fill_link_info) {
3936 		err = link->ops->fill_link_info(link, &info);
3937 		if (err)
3938 			return err;
3939 	}
3940 
3941 	if (copy_to_user(uinfo, &info, info_len) ||
3942 	    put_user(info_len, &uattr->info.info_len))
3943 		return -EFAULT;
3944 
3945 	return 0;
3946 }
3947 
3948 
3949 #define BPF_OBJ_GET_INFO_BY_FD_LAST_FIELD info.info
3950 
3951 static int bpf_obj_get_info_by_fd(const union bpf_attr *attr,
3952 				  union bpf_attr __user *uattr)
3953 {
3954 	int ufd = attr->info.bpf_fd;
3955 	struct fd f;
3956 	int err;
3957 
3958 	if (CHECK_ATTR(BPF_OBJ_GET_INFO_BY_FD))
3959 		return -EINVAL;
3960 
3961 	f = fdget(ufd);
3962 	if (!f.file)
3963 		return -EBADFD;
3964 
3965 	if (f.file->f_op == &bpf_prog_fops)
3966 		err = bpf_prog_get_info_by_fd(f.file, f.file->private_data, attr,
3967 					      uattr);
3968 	else if (f.file->f_op == &bpf_map_fops)
3969 		err = bpf_map_get_info_by_fd(f.file, f.file->private_data, attr,
3970 					     uattr);
3971 	else if (f.file->f_op == &btf_fops)
3972 		err = bpf_btf_get_info_by_fd(f.file, f.file->private_data, attr, uattr);
3973 	else if (f.file->f_op == &bpf_link_fops)
3974 		err = bpf_link_get_info_by_fd(f.file, f.file->private_data,
3975 					      attr, uattr);
3976 	else
3977 		err = -EINVAL;
3978 
3979 	fdput(f);
3980 	return err;
3981 }
3982 
3983 #define BPF_BTF_LOAD_LAST_FIELD btf_log_level
3984 
3985 static int bpf_btf_load(const union bpf_attr *attr, bpfptr_t uattr)
3986 {
3987 	if (CHECK_ATTR(BPF_BTF_LOAD))
3988 		return -EINVAL;
3989 
3990 	if (!bpf_capable())
3991 		return -EPERM;
3992 
3993 	return btf_new_fd(attr, uattr);
3994 }
3995 
3996 #define BPF_BTF_GET_FD_BY_ID_LAST_FIELD btf_id
3997 
3998 static int bpf_btf_get_fd_by_id(const union bpf_attr *attr)
3999 {
4000 	if (CHECK_ATTR(BPF_BTF_GET_FD_BY_ID))
4001 		return -EINVAL;
4002 
4003 	if (!capable(CAP_SYS_ADMIN))
4004 		return -EPERM;
4005 
4006 	return btf_get_fd_by_id(attr->btf_id);
4007 }
4008 
4009 static int bpf_task_fd_query_copy(const union bpf_attr *attr,
4010 				    union bpf_attr __user *uattr,
4011 				    u32 prog_id, u32 fd_type,
4012 				    const char *buf, u64 probe_offset,
4013 				    u64 probe_addr)
4014 {
4015 	char __user *ubuf = u64_to_user_ptr(attr->task_fd_query.buf);
4016 	u32 len = buf ? strlen(buf) : 0, input_len;
4017 	int err = 0;
4018 
4019 	if (put_user(len, &uattr->task_fd_query.buf_len))
4020 		return -EFAULT;
4021 	input_len = attr->task_fd_query.buf_len;
4022 	if (input_len && ubuf) {
4023 		if (!len) {
4024 			/* nothing to copy, just make ubuf NULL terminated */
4025 			char zero = '\0';
4026 
4027 			if (put_user(zero, ubuf))
4028 				return -EFAULT;
4029 		} else if (input_len >= len + 1) {
4030 			/* ubuf can hold the string with NULL terminator */
4031 			if (copy_to_user(ubuf, buf, len + 1))
4032 				return -EFAULT;
4033 		} else {
4034 			/* ubuf cannot hold the string with NULL terminator,
4035 			 * do a partial copy with NULL terminator.
4036 			 */
4037 			char zero = '\0';
4038 
4039 			err = -ENOSPC;
4040 			if (copy_to_user(ubuf, buf, input_len - 1))
4041 				return -EFAULT;
4042 			if (put_user(zero, ubuf + input_len - 1))
4043 				return -EFAULT;
4044 		}
4045 	}
4046 
4047 	if (put_user(prog_id, &uattr->task_fd_query.prog_id) ||
4048 	    put_user(fd_type, &uattr->task_fd_query.fd_type) ||
4049 	    put_user(probe_offset, &uattr->task_fd_query.probe_offset) ||
4050 	    put_user(probe_addr, &uattr->task_fd_query.probe_addr))
4051 		return -EFAULT;
4052 
4053 	return err;
4054 }
4055 
4056 #define BPF_TASK_FD_QUERY_LAST_FIELD task_fd_query.probe_addr
4057 
4058 static int bpf_task_fd_query(const union bpf_attr *attr,
4059 			     union bpf_attr __user *uattr)
4060 {
4061 	pid_t pid = attr->task_fd_query.pid;
4062 	u32 fd = attr->task_fd_query.fd;
4063 	const struct perf_event *event;
4064 	struct task_struct *task;
4065 	struct file *file;
4066 	int err;
4067 
4068 	if (CHECK_ATTR(BPF_TASK_FD_QUERY))
4069 		return -EINVAL;
4070 
4071 	if (!capable(CAP_SYS_ADMIN))
4072 		return -EPERM;
4073 
4074 	if (attr->task_fd_query.flags != 0)
4075 		return -EINVAL;
4076 
4077 	task = get_pid_task(find_vpid(pid), PIDTYPE_PID);
4078 	if (!task)
4079 		return -ENOENT;
4080 
4081 	err = 0;
4082 	file = fget_task(task, fd);
4083 	put_task_struct(task);
4084 	if (!file)
4085 		return -EBADF;
4086 
4087 	if (file->f_op == &bpf_link_fops) {
4088 		struct bpf_link *link = file->private_data;
4089 
4090 		if (link->ops == &bpf_raw_tp_link_lops) {
4091 			struct bpf_raw_tp_link *raw_tp =
4092 				container_of(link, struct bpf_raw_tp_link, link);
4093 			struct bpf_raw_event_map *btp = raw_tp->btp;
4094 
4095 			err = bpf_task_fd_query_copy(attr, uattr,
4096 						     raw_tp->link.prog->aux->id,
4097 						     BPF_FD_TYPE_RAW_TRACEPOINT,
4098 						     btp->tp->name, 0, 0);
4099 			goto put_file;
4100 		}
4101 		goto out_not_supp;
4102 	}
4103 
4104 	event = perf_get_event(file);
4105 	if (!IS_ERR(event)) {
4106 		u64 probe_offset, probe_addr;
4107 		u32 prog_id, fd_type;
4108 		const char *buf;
4109 
4110 		err = bpf_get_perf_event_info(event, &prog_id, &fd_type,
4111 					      &buf, &probe_offset,
4112 					      &probe_addr);
4113 		if (!err)
4114 			err = bpf_task_fd_query_copy(attr, uattr, prog_id,
4115 						     fd_type, buf,
4116 						     probe_offset,
4117 						     probe_addr);
4118 		goto put_file;
4119 	}
4120 
4121 out_not_supp:
4122 	err = -ENOTSUPP;
4123 put_file:
4124 	fput(file);
4125 	return err;
4126 }
4127 
4128 #define BPF_MAP_BATCH_LAST_FIELD batch.flags
4129 
4130 #define BPF_DO_BATCH(fn)			\
4131 	do {					\
4132 		if (!fn) {			\
4133 			err = -ENOTSUPP;	\
4134 			goto err_put;		\
4135 		}				\
4136 		err = fn(map, attr, uattr);	\
4137 	} while (0)
4138 
4139 static int bpf_map_do_batch(const union bpf_attr *attr,
4140 			    union bpf_attr __user *uattr,
4141 			    int cmd)
4142 {
4143 	struct bpf_map *map;
4144 	int err, ufd;
4145 	struct fd f;
4146 
4147 	if (CHECK_ATTR(BPF_MAP_BATCH))
4148 		return -EINVAL;
4149 
4150 	ufd = attr->batch.map_fd;
4151 	f = fdget(ufd);
4152 	map = __bpf_map_get(f);
4153 	if (IS_ERR(map))
4154 		return PTR_ERR(map);
4155 
4156 	if ((cmd == BPF_MAP_LOOKUP_BATCH ||
4157 	     cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH) &&
4158 	    !(map_get_sys_perms(map, f) & FMODE_CAN_READ)) {
4159 		err = -EPERM;
4160 		goto err_put;
4161 	}
4162 
4163 	if (cmd != BPF_MAP_LOOKUP_BATCH &&
4164 	    !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
4165 		err = -EPERM;
4166 		goto err_put;
4167 	}
4168 
4169 	if (cmd == BPF_MAP_LOOKUP_BATCH)
4170 		BPF_DO_BATCH(map->ops->map_lookup_batch);
4171 	else if (cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH)
4172 		BPF_DO_BATCH(map->ops->map_lookup_and_delete_batch);
4173 	else if (cmd == BPF_MAP_UPDATE_BATCH)
4174 		BPF_DO_BATCH(map->ops->map_update_batch);
4175 	else
4176 		BPF_DO_BATCH(map->ops->map_delete_batch);
4177 
4178 err_put:
4179 	fdput(f);
4180 	return err;
4181 }
4182 
4183 static int tracing_bpf_link_attach(const union bpf_attr *attr, bpfptr_t uattr,
4184 				   struct bpf_prog *prog)
4185 {
4186 	if (attr->link_create.attach_type != prog->expected_attach_type)
4187 		return -EINVAL;
4188 
4189 	if (prog->expected_attach_type == BPF_TRACE_ITER)
4190 		return bpf_iter_link_attach(attr, uattr, prog);
4191 	else if (prog->type == BPF_PROG_TYPE_EXT)
4192 		return bpf_tracing_prog_attach(prog,
4193 					       attr->link_create.target_fd,
4194 					       attr->link_create.target_btf_id);
4195 	return -EINVAL;
4196 }
4197 
4198 #define BPF_LINK_CREATE_LAST_FIELD link_create.iter_info_len
4199 static int link_create(union bpf_attr *attr, bpfptr_t uattr)
4200 {
4201 	enum bpf_prog_type ptype;
4202 	struct bpf_prog *prog;
4203 	int ret;
4204 
4205 	if (CHECK_ATTR(BPF_LINK_CREATE))
4206 		return -EINVAL;
4207 
4208 	prog = bpf_prog_get(attr->link_create.prog_fd);
4209 	if (IS_ERR(prog))
4210 		return PTR_ERR(prog);
4211 
4212 	ret = bpf_prog_attach_check_attach_type(prog,
4213 						attr->link_create.attach_type);
4214 	if (ret)
4215 		goto out;
4216 
4217 	switch (prog->type) {
4218 	case BPF_PROG_TYPE_EXT:
4219 		ret = tracing_bpf_link_attach(attr, uattr, prog);
4220 		goto out;
4221 	case BPF_PROG_TYPE_PERF_EVENT:
4222 	case BPF_PROG_TYPE_KPROBE:
4223 	case BPF_PROG_TYPE_TRACEPOINT:
4224 		if (attr->link_create.attach_type != BPF_PERF_EVENT) {
4225 			ret = -EINVAL;
4226 			goto out;
4227 		}
4228 		ptype = prog->type;
4229 		break;
4230 	default:
4231 		ptype = attach_type_to_prog_type(attr->link_create.attach_type);
4232 		if (ptype == BPF_PROG_TYPE_UNSPEC || ptype != prog->type) {
4233 			ret = -EINVAL;
4234 			goto out;
4235 		}
4236 		break;
4237 	}
4238 
4239 	switch (ptype) {
4240 	case BPF_PROG_TYPE_CGROUP_SKB:
4241 	case BPF_PROG_TYPE_CGROUP_SOCK:
4242 	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
4243 	case BPF_PROG_TYPE_SOCK_OPS:
4244 	case BPF_PROG_TYPE_CGROUP_DEVICE:
4245 	case BPF_PROG_TYPE_CGROUP_SYSCTL:
4246 	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
4247 		ret = cgroup_bpf_link_attach(attr, prog);
4248 		break;
4249 	case BPF_PROG_TYPE_TRACING:
4250 		ret = tracing_bpf_link_attach(attr, uattr, prog);
4251 		break;
4252 	case BPF_PROG_TYPE_FLOW_DISSECTOR:
4253 	case BPF_PROG_TYPE_SK_LOOKUP:
4254 		ret = netns_bpf_link_create(attr, prog);
4255 		break;
4256 #ifdef CONFIG_NET
4257 	case BPF_PROG_TYPE_XDP:
4258 		ret = bpf_xdp_link_attach(attr, prog);
4259 		break;
4260 #endif
4261 #ifdef CONFIG_PERF_EVENTS
4262 	case BPF_PROG_TYPE_PERF_EVENT:
4263 	case BPF_PROG_TYPE_TRACEPOINT:
4264 	case BPF_PROG_TYPE_KPROBE:
4265 		ret = bpf_perf_link_attach(attr, prog);
4266 		break;
4267 #endif
4268 	default:
4269 		ret = -EINVAL;
4270 	}
4271 
4272 out:
4273 	if (ret < 0)
4274 		bpf_prog_put(prog);
4275 	return ret;
4276 }
4277 
4278 #define BPF_LINK_UPDATE_LAST_FIELD link_update.old_prog_fd
4279 
4280 static int link_update(union bpf_attr *attr)
4281 {
4282 	struct bpf_prog *old_prog = NULL, *new_prog;
4283 	struct bpf_link *link;
4284 	u32 flags;
4285 	int ret;
4286 
4287 	if (CHECK_ATTR(BPF_LINK_UPDATE))
4288 		return -EINVAL;
4289 
4290 	flags = attr->link_update.flags;
4291 	if (flags & ~BPF_F_REPLACE)
4292 		return -EINVAL;
4293 
4294 	link = bpf_link_get_from_fd(attr->link_update.link_fd);
4295 	if (IS_ERR(link))
4296 		return PTR_ERR(link);
4297 
4298 	new_prog = bpf_prog_get(attr->link_update.new_prog_fd);
4299 	if (IS_ERR(new_prog)) {
4300 		ret = PTR_ERR(new_prog);
4301 		goto out_put_link;
4302 	}
4303 
4304 	if (flags & BPF_F_REPLACE) {
4305 		old_prog = bpf_prog_get(attr->link_update.old_prog_fd);
4306 		if (IS_ERR(old_prog)) {
4307 			ret = PTR_ERR(old_prog);
4308 			old_prog = NULL;
4309 			goto out_put_progs;
4310 		}
4311 	} else if (attr->link_update.old_prog_fd) {
4312 		ret = -EINVAL;
4313 		goto out_put_progs;
4314 	}
4315 
4316 	if (link->ops->update_prog)
4317 		ret = link->ops->update_prog(link, new_prog, old_prog);
4318 	else
4319 		ret = -EINVAL;
4320 
4321 out_put_progs:
4322 	if (old_prog)
4323 		bpf_prog_put(old_prog);
4324 	if (ret)
4325 		bpf_prog_put(new_prog);
4326 out_put_link:
4327 	bpf_link_put(link);
4328 	return ret;
4329 }
4330 
4331 #define BPF_LINK_DETACH_LAST_FIELD link_detach.link_fd
4332 
4333 static int link_detach(union bpf_attr *attr)
4334 {
4335 	struct bpf_link *link;
4336 	int ret;
4337 
4338 	if (CHECK_ATTR(BPF_LINK_DETACH))
4339 		return -EINVAL;
4340 
4341 	link = bpf_link_get_from_fd(attr->link_detach.link_fd);
4342 	if (IS_ERR(link))
4343 		return PTR_ERR(link);
4344 
4345 	if (link->ops->detach)
4346 		ret = link->ops->detach(link);
4347 	else
4348 		ret = -EOPNOTSUPP;
4349 
4350 	bpf_link_put(link);
4351 	return ret;
4352 }
4353 
4354 static struct bpf_link *bpf_link_inc_not_zero(struct bpf_link *link)
4355 {
4356 	return atomic64_fetch_add_unless(&link->refcnt, 1, 0) ? link : ERR_PTR(-ENOENT);
4357 }
4358 
4359 struct bpf_link *bpf_link_by_id(u32 id)
4360 {
4361 	struct bpf_link *link;
4362 
4363 	if (!id)
4364 		return ERR_PTR(-ENOENT);
4365 
4366 	spin_lock_bh(&link_idr_lock);
4367 	/* before link is "settled", ID is 0, pretend it doesn't exist yet */
4368 	link = idr_find(&link_idr, id);
4369 	if (link) {
4370 		if (link->id)
4371 			link = bpf_link_inc_not_zero(link);
4372 		else
4373 			link = ERR_PTR(-EAGAIN);
4374 	} else {
4375 		link = ERR_PTR(-ENOENT);
4376 	}
4377 	spin_unlock_bh(&link_idr_lock);
4378 	return link;
4379 }
4380 
4381 #define BPF_LINK_GET_FD_BY_ID_LAST_FIELD link_id
4382 
4383 static int bpf_link_get_fd_by_id(const union bpf_attr *attr)
4384 {
4385 	struct bpf_link *link;
4386 	u32 id = attr->link_id;
4387 	int fd;
4388 
4389 	if (CHECK_ATTR(BPF_LINK_GET_FD_BY_ID))
4390 		return -EINVAL;
4391 
4392 	if (!capable(CAP_SYS_ADMIN))
4393 		return -EPERM;
4394 
4395 	link = bpf_link_by_id(id);
4396 	if (IS_ERR(link))
4397 		return PTR_ERR(link);
4398 
4399 	fd = bpf_link_new_fd(link);
4400 	if (fd < 0)
4401 		bpf_link_put(link);
4402 
4403 	return fd;
4404 }
4405 
4406 DEFINE_MUTEX(bpf_stats_enabled_mutex);
4407 
4408 static int bpf_stats_release(struct inode *inode, struct file *file)
4409 {
4410 	mutex_lock(&bpf_stats_enabled_mutex);
4411 	static_key_slow_dec(&bpf_stats_enabled_key.key);
4412 	mutex_unlock(&bpf_stats_enabled_mutex);
4413 	return 0;
4414 }
4415 
4416 static const struct file_operations bpf_stats_fops = {
4417 	.release = bpf_stats_release,
4418 };
4419 
4420 static int bpf_enable_runtime_stats(void)
4421 {
4422 	int fd;
4423 
4424 	mutex_lock(&bpf_stats_enabled_mutex);
4425 
4426 	/* Set a very high limit to avoid overflow */
4427 	if (static_key_count(&bpf_stats_enabled_key.key) > INT_MAX / 2) {
4428 		mutex_unlock(&bpf_stats_enabled_mutex);
4429 		return -EBUSY;
4430 	}
4431 
4432 	fd = anon_inode_getfd("bpf-stats", &bpf_stats_fops, NULL, O_CLOEXEC);
4433 	if (fd >= 0)
4434 		static_key_slow_inc(&bpf_stats_enabled_key.key);
4435 
4436 	mutex_unlock(&bpf_stats_enabled_mutex);
4437 	return fd;
4438 }
4439 
4440 #define BPF_ENABLE_STATS_LAST_FIELD enable_stats.type
4441 
4442 static int bpf_enable_stats(union bpf_attr *attr)
4443 {
4444 
4445 	if (CHECK_ATTR(BPF_ENABLE_STATS))
4446 		return -EINVAL;
4447 
4448 	if (!capable(CAP_SYS_ADMIN))
4449 		return -EPERM;
4450 
4451 	switch (attr->enable_stats.type) {
4452 	case BPF_STATS_RUN_TIME:
4453 		return bpf_enable_runtime_stats();
4454 	default:
4455 		break;
4456 	}
4457 	return -EINVAL;
4458 }
4459 
4460 #define BPF_ITER_CREATE_LAST_FIELD iter_create.flags
4461 
4462 static int bpf_iter_create(union bpf_attr *attr)
4463 {
4464 	struct bpf_link *link;
4465 	int err;
4466 
4467 	if (CHECK_ATTR(BPF_ITER_CREATE))
4468 		return -EINVAL;
4469 
4470 	if (attr->iter_create.flags)
4471 		return -EINVAL;
4472 
4473 	link = bpf_link_get_from_fd(attr->iter_create.link_fd);
4474 	if (IS_ERR(link))
4475 		return PTR_ERR(link);
4476 
4477 	err = bpf_iter_new_fd(link);
4478 	bpf_link_put(link);
4479 
4480 	return err;
4481 }
4482 
4483 #define BPF_PROG_BIND_MAP_LAST_FIELD prog_bind_map.flags
4484 
4485 static int bpf_prog_bind_map(union bpf_attr *attr)
4486 {
4487 	struct bpf_prog *prog;
4488 	struct bpf_map *map;
4489 	struct bpf_map **used_maps_old, **used_maps_new;
4490 	int i, ret = 0;
4491 
4492 	if (CHECK_ATTR(BPF_PROG_BIND_MAP))
4493 		return -EINVAL;
4494 
4495 	if (attr->prog_bind_map.flags)
4496 		return -EINVAL;
4497 
4498 	prog = bpf_prog_get(attr->prog_bind_map.prog_fd);
4499 	if (IS_ERR(prog))
4500 		return PTR_ERR(prog);
4501 
4502 	map = bpf_map_get(attr->prog_bind_map.map_fd);
4503 	if (IS_ERR(map)) {
4504 		ret = PTR_ERR(map);
4505 		goto out_prog_put;
4506 	}
4507 
4508 	mutex_lock(&prog->aux->used_maps_mutex);
4509 
4510 	used_maps_old = prog->aux->used_maps;
4511 
4512 	for (i = 0; i < prog->aux->used_map_cnt; i++)
4513 		if (used_maps_old[i] == map) {
4514 			bpf_map_put(map);
4515 			goto out_unlock;
4516 		}
4517 
4518 	used_maps_new = kmalloc_array(prog->aux->used_map_cnt + 1,
4519 				      sizeof(used_maps_new[0]),
4520 				      GFP_KERNEL);
4521 	if (!used_maps_new) {
4522 		ret = -ENOMEM;
4523 		goto out_unlock;
4524 	}
4525 
4526 	memcpy(used_maps_new, used_maps_old,
4527 	       sizeof(used_maps_old[0]) * prog->aux->used_map_cnt);
4528 	used_maps_new[prog->aux->used_map_cnt] = map;
4529 
4530 	prog->aux->used_map_cnt++;
4531 	prog->aux->used_maps = used_maps_new;
4532 
4533 	kfree(used_maps_old);
4534 
4535 out_unlock:
4536 	mutex_unlock(&prog->aux->used_maps_mutex);
4537 
4538 	if (ret)
4539 		bpf_map_put(map);
4540 out_prog_put:
4541 	bpf_prog_put(prog);
4542 	return ret;
4543 }
4544 
4545 static int __sys_bpf(int cmd, bpfptr_t uattr, unsigned int size)
4546 {
4547 	union bpf_attr attr;
4548 	int err;
4549 
4550 	if (sysctl_unprivileged_bpf_disabled && !bpf_capable())
4551 		return -EPERM;
4552 
4553 	err = bpf_check_uarg_tail_zero(uattr, sizeof(attr), size);
4554 	if (err)
4555 		return err;
4556 	size = min_t(u32, size, sizeof(attr));
4557 
4558 	/* copy attributes from user space, may be less than sizeof(bpf_attr) */
4559 	memset(&attr, 0, sizeof(attr));
4560 	if (copy_from_bpfptr(&attr, uattr, size) != 0)
4561 		return -EFAULT;
4562 
4563 	err = security_bpf(cmd, &attr, size);
4564 	if (err < 0)
4565 		return err;
4566 
4567 	switch (cmd) {
4568 	case BPF_MAP_CREATE:
4569 		err = map_create(&attr);
4570 		break;
4571 	case BPF_MAP_LOOKUP_ELEM:
4572 		err = map_lookup_elem(&attr);
4573 		break;
4574 	case BPF_MAP_UPDATE_ELEM:
4575 		err = map_update_elem(&attr, uattr);
4576 		break;
4577 	case BPF_MAP_DELETE_ELEM:
4578 		err = map_delete_elem(&attr);
4579 		break;
4580 	case BPF_MAP_GET_NEXT_KEY:
4581 		err = map_get_next_key(&attr);
4582 		break;
4583 	case BPF_MAP_FREEZE:
4584 		err = map_freeze(&attr);
4585 		break;
4586 	case BPF_PROG_LOAD:
4587 		err = bpf_prog_load(&attr, uattr);
4588 		break;
4589 	case BPF_OBJ_PIN:
4590 		err = bpf_obj_pin(&attr);
4591 		break;
4592 	case BPF_OBJ_GET:
4593 		err = bpf_obj_get(&attr);
4594 		break;
4595 	case BPF_PROG_ATTACH:
4596 		err = bpf_prog_attach(&attr);
4597 		break;
4598 	case BPF_PROG_DETACH:
4599 		err = bpf_prog_detach(&attr);
4600 		break;
4601 	case BPF_PROG_QUERY:
4602 		err = bpf_prog_query(&attr, uattr.user);
4603 		break;
4604 	case BPF_PROG_TEST_RUN:
4605 		err = bpf_prog_test_run(&attr, uattr.user);
4606 		break;
4607 	case BPF_PROG_GET_NEXT_ID:
4608 		err = bpf_obj_get_next_id(&attr, uattr.user,
4609 					  &prog_idr, &prog_idr_lock);
4610 		break;
4611 	case BPF_MAP_GET_NEXT_ID:
4612 		err = bpf_obj_get_next_id(&attr, uattr.user,
4613 					  &map_idr, &map_idr_lock);
4614 		break;
4615 	case BPF_BTF_GET_NEXT_ID:
4616 		err = bpf_obj_get_next_id(&attr, uattr.user,
4617 					  &btf_idr, &btf_idr_lock);
4618 		break;
4619 	case BPF_PROG_GET_FD_BY_ID:
4620 		err = bpf_prog_get_fd_by_id(&attr);
4621 		break;
4622 	case BPF_MAP_GET_FD_BY_ID:
4623 		err = bpf_map_get_fd_by_id(&attr);
4624 		break;
4625 	case BPF_OBJ_GET_INFO_BY_FD:
4626 		err = bpf_obj_get_info_by_fd(&attr, uattr.user);
4627 		break;
4628 	case BPF_RAW_TRACEPOINT_OPEN:
4629 		err = bpf_raw_tracepoint_open(&attr);
4630 		break;
4631 	case BPF_BTF_LOAD:
4632 		err = bpf_btf_load(&attr, uattr);
4633 		break;
4634 	case BPF_BTF_GET_FD_BY_ID:
4635 		err = bpf_btf_get_fd_by_id(&attr);
4636 		break;
4637 	case BPF_TASK_FD_QUERY:
4638 		err = bpf_task_fd_query(&attr, uattr.user);
4639 		break;
4640 	case BPF_MAP_LOOKUP_AND_DELETE_ELEM:
4641 		err = map_lookup_and_delete_elem(&attr);
4642 		break;
4643 	case BPF_MAP_LOOKUP_BATCH:
4644 		err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_LOOKUP_BATCH);
4645 		break;
4646 	case BPF_MAP_LOOKUP_AND_DELETE_BATCH:
4647 		err = bpf_map_do_batch(&attr, uattr.user,
4648 				       BPF_MAP_LOOKUP_AND_DELETE_BATCH);
4649 		break;
4650 	case BPF_MAP_UPDATE_BATCH:
4651 		err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_UPDATE_BATCH);
4652 		break;
4653 	case BPF_MAP_DELETE_BATCH:
4654 		err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_DELETE_BATCH);
4655 		break;
4656 	case BPF_LINK_CREATE:
4657 		err = link_create(&attr, uattr);
4658 		break;
4659 	case BPF_LINK_UPDATE:
4660 		err = link_update(&attr);
4661 		break;
4662 	case BPF_LINK_GET_FD_BY_ID:
4663 		err = bpf_link_get_fd_by_id(&attr);
4664 		break;
4665 	case BPF_LINK_GET_NEXT_ID:
4666 		err = bpf_obj_get_next_id(&attr, uattr.user,
4667 					  &link_idr, &link_idr_lock);
4668 		break;
4669 	case BPF_ENABLE_STATS:
4670 		err = bpf_enable_stats(&attr);
4671 		break;
4672 	case BPF_ITER_CREATE:
4673 		err = bpf_iter_create(&attr);
4674 		break;
4675 	case BPF_LINK_DETACH:
4676 		err = link_detach(&attr);
4677 		break;
4678 	case BPF_PROG_BIND_MAP:
4679 		err = bpf_prog_bind_map(&attr);
4680 		break;
4681 	default:
4682 		err = -EINVAL;
4683 		break;
4684 	}
4685 
4686 	return err;
4687 }
4688 
4689 SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size)
4690 {
4691 	return __sys_bpf(cmd, USER_BPFPTR(uattr), size);
4692 }
4693 
4694 static bool syscall_prog_is_valid_access(int off, int size,
4695 					 enum bpf_access_type type,
4696 					 const struct bpf_prog *prog,
4697 					 struct bpf_insn_access_aux *info)
4698 {
4699 	if (off < 0 || off >= U16_MAX)
4700 		return false;
4701 	if (off % size != 0)
4702 		return false;
4703 	return true;
4704 }
4705 
4706 BPF_CALL_3(bpf_sys_bpf, int, cmd, void *, attr, u32, attr_size)
4707 {
4708 	switch (cmd) {
4709 	case BPF_MAP_CREATE:
4710 	case BPF_MAP_UPDATE_ELEM:
4711 	case BPF_MAP_FREEZE:
4712 	case BPF_PROG_LOAD:
4713 	case BPF_BTF_LOAD:
4714 		break;
4715 	/* case BPF_PROG_TEST_RUN:
4716 	 * is not part of this list to prevent recursive test_run
4717 	 */
4718 	default:
4719 		return -EINVAL;
4720 	}
4721 	return __sys_bpf(cmd, KERNEL_BPFPTR(attr), attr_size);
4722 }
4723 
4724 static const struct bpf_func_proto bpf_sys_bpf_proto = {
4725 	.func		= bpf_sys_bpf,
4726 	.gpl_only	= false,
4727 	.ret_type	= RET_INTEGER,
4728 	.arg1_type	= ARG_ANYTHING,
4729 	.arg2_type	= ARG_PTR_TO_MEM,
4730 	.arg3_type	= ARG_CONST_SIZE,
4731 };
4732 
4733 const struct bpf_func_proto * __weak
4734 tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
4735 {
4736 	return bpf_base_func_proto(func_id);
4737 }
4738 
4739 BPF_CALL_1(bpf_sys_close, u32, fd)
4740 {
4741 	/* When bpf program calls this helper there should not be
4742 	 * an fdget() without matching completed fdput().
4743 	 * This helper is allowed in the following callchain only:
4744 	 * sys_bpf->prog_test_run->bpf_prog->bpf_sys_close
4745 	 */
4746 	return close_fd(fd);
4747 }
4748 
4749 static const struct bpf_func_proto bpf_sys_close_proto = {
4750 	.func		= bpf_sys_close,
4751 	.gpl_only	= false,
4752 	.ret_type	= RET_INTEGER,
4753 	.arg1_type	= ARG_ANYTHING,
4754 };
4755 
4756 static const struct bpf_func_proto *
4757 syscall_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
4758 {
4759 	switch (func_id) {
4760 	case BPF_FUNC_sys_bpf:
4761 		return &bpf_sys_bpf_proto;
4762 	case BPF_FUNC_btf_find_by_name_kind:
4763 		return &bpf_btf_find_by_name_kind_proto;
4764 	case BPF_FUNC_sys_close:
4765 		return &bpf_sys_close_proto;
4766 	default:
4767 		return tracing_prog_func_proto(func_id, prog);
4768 	}
4769 }
4770 
4771 const struct bpf_verifier_ops bpf_syscall_verifier_ops = {
4772 	.get_func_proto  = syscall_prog_func_proto,
4773 	.is_valid_access = syscall_prog_is_valid_access,
4774 };
4775 
4776 const struct bpf_prog_ops bpf_syscall_prog_ops = {
4777 	.test_run = bpf_prog_test_run_syscall,
4778 };
4779