xref: /linux/kernel/bpf/syscall.c (revision 7f71507851fc7764b36a3221839607d3a45c2025)
1 // SPDX-License-Identifier: GPL-2.0-only
2 /* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
3  */
4 #include <linux/bpf.h>
5 #include <linux/bpf-cgroup.h>
6 #include <linux/bpf_trace.h>
7 #include <linux/bpf_lirc.h>
8 #include <linux/bpf_verifier.h>
9 #include <linux/bsearch.h>
10 #include <linux/btf.h>
11 #include <linux/syscalls.h>
12 #include <linux/slab.h>
13 #include <linux/sched/signal.h>
14 #include <linux/vmalloc.h>
15 #include <linux/mmzone.h>
16 #include <linux/anon_inodes.h>
17 #include <linux/fdtable.h>
18 #include <linux/file.h>
19 #include <linux/fs.h>
20 #include <linux/license.h>
21 #include <linux/filter.h>
22 #include <linux/kernel.h>
23 #include <linux/idr.h>
24 #include <linux/cred.h>
25 #include <linux/timekeeping.h>
26 #include <linux/ctype.h>
27 #include <linux/nospec.h>
28 #include <linux/audit.h>
29 #include <uapi/linux/btf.h>
30 #include <linux/pgtable.h>
31 #include <linux/bpf_lsm.h>
32 #include <linux/poll.h>
33 #include <linux/sort.h>
34 #include <linux/bpf-netns.h>
35 #include <linux/rcupdate_trace.h>
36 #include <linux/memcontrol.h>
37 #include <linux/trace_events.h>
38 #include <linux/tracepoint.h>
39 
40 #include <net/netfilter/nf_bpf_link.h>
41 #include <net/netkit.h>
42 #include <net/tcx.h>
43 
44 #define IS_FD_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || \
45 			  (map)->map_type == BPF_MAP_TYPE_CGROUP_ARRAY || \
46 			  (map)->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS)
47 #define IS_FD_PROG_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PROG_ARRAY)
48 #define IS_FD_HASH(map) ((map)->map_type == BPF_MAP_TYPE_HASH_OF_MAPS)
49 #define IS_FD_MAP(map) (IS_FD_ARRAY(map) || IS_FD_PROG_ARRAY(map) || \
50 			IS_FD_HASH(map))
51 
52 #define BPF_OBJ_FLAG_MASK   (BPF_F_RDONLY | BPF_F_WRONLY)
53 
54 DEFINE_PER_CPU(int, bpf_prog_active);
55 static DEFINE_IDR(prog_idr);
56 static DEFINE_SPINLOCK(prog_idr_lock);
57 static DEFINE_IDR(map_idr);
58 static DEFINE_SPINLOCK(map_idr_lock);
59 static DEFINE_IDR(link_idr);
60 static DEFINE_SPINLOCK(link_idr_lock);
61 
62 int sysctl_unprivileged_bpf_disabled __read_mostly =
63 	IS_BUILTIN(CONFIG_BPF_UNPRIV_DEFAULT_OFF) ? 2 : 0;
64 
65 static const struct bpf_map_ops * const bpf_map_types[] = {
66 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type)
67 #define BPF_MAP_TYPE(_id, _ops) \
68 	[_id] = &_ops,
69 #define BPF_LINK_TYPE(_id, _name)
70 #include <linux/bpf_types.h>
71 #undef BPF_PROG_TYPE
72 #undef BPF_MAP_TYPE
73 #undef BPF_LINK_TYPE
74 };
75 
76 /*
77  * If we're handed a bigger struct than we know of, ensure all the unknown bits
78  * are 0 - i.e. new user-space does not rely on any kernel feature extensions
79  * we don't know about yet.
80  *
81  * There is a ToCToU between this function call and the following
82  * copy_from_user() call. However, this is not a concern since this function is
83  * meant to be a future-proofing of bits.
84  */
85 int bpf_check_uarg_tail_zero(bpfptr_t uaddr,
86 			     size_t expected_size,
87 			     size_t actual_size)
88 {
89 	int res;
90 
91 	if (unlikely(actual_size > PAGE_SIZE))	/* silly large */
92 		return -E2BIG;
93 
94 	if (actual_size <= expected_size)
95 		return 0;
96 
97 	if (uaddr.is_kernel)
98 		res = memchr_inv(uaddr.kernel + expected_size, 0,
99 				 actual_size - expected_size) == NULL;
100 	else
101 		res = check_zeroed_user(uaddr.user + expected_size,
102 					actual_size - expected_size);
103 	if (res < 0)
104 		return res;
105 	return res ? 0 : -E2BIG;
106 }
107 
108 const struct bpf_map_ops bpf_map_offload_ops = {
109 	.map_meta_equal = bpf_map_meta_equal,
110 	.map_alloc = bpf_map_offload_map_alloc,
111 	.map_free = bpf_map_offload_map_free,
112 	.map_check_btf = map_check_no_btf,
113 	.map_mem_usage = bpf_map_offload_map_mem_usage,
114 };
115 
116 static void bpf_map_write_active_inc(struct bpf_map *map)
117 {
118 	atomic64_inc(&map->writecnt);
119 }
120 
121 static void bpf_map_write_active_dec(struct bpf_map *map)
122 {
123 	atomic64_dec(&map->writecnt);
124 }
125 
126 bool bpf_map_write_active(const struct bpf_map *map)
127 {
128 	return atomic64_read(&map->writecnt) != 0;
129 }
130 
131 static u32 bpf_map_value_size(const struct bpf_map *map)
132 {
133 	if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
134 	    map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH ||
135 	    map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY ||
136 	    map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE)
137 		return round_up(map->value_size, 8) * num_possible_cpus();
138 	else if (IS_FD_MAP(map))
139 		return sizeof(u32);
140 	else
141 		return  map->value_size;
142 }
143 
144 static void maybe_wait_bpf_programs(struct bpf_map *map)
145 {
146 	/* Wait for any running non-sleepable BPF programs to complete so that
147 	 * userspace, when we return to it, knows that all non-sleepable
148 	 * programs that could be running use the new map value. For sleepable
149 	 * BPF programs, synchronize_rcu_tasks_trace() should be used to wait
150 	 * for the completions of these programs, but considering the waiting
151 	 * time can be very long and userspace may think it will hang forever,
152 	 * so don't handle sleepable BPF programs now.
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 void unpin_uptr_kaddr(void *kaddr)
160 {
161 	if (kaddr)
162 		unpin_user_page(virt_to_page(kaddr));
163 }
164 
165 static void __bpf_obj_unpin_uptrs(struct btf_record *rec, u32 cnt, void *obj)
166 {
167 	const struct btf_field *field;
168 	void **uptr_addr;
169 	int i;
170 
171 	for (i = 0, field = rec->fields; i < cnt; i++, field++) {
172 		if (field->type != BPF_UPTR)
173 			continue;
174 
175 		uptr_addr = obj + field->offset;
176 		unpin_uptr_kaddr(*uptr_addr);
177 	}
178 }
179 
180 static void bpf_obj_unpin_uptrs(struct btf_record *rec, void *obj)
181 {
182 	if (!btf_record_has_field(rec, BPF_UPTR))
183 		return;
184 
185 	__bpf_obj_unpin_uptrs(rec, rec->cnt, obj);
186 }
187 
188 static int bpf_obj_pin_uptrs(struct btf_record *rec, void *obj)
189 {
190 	const struct btf_field *field;
191 	const struct btf_type *t;
192 	unsigned long start, end;
193 	struct page *page;
194 	void **uptr_addr;
195 	int i, err;
196 
197 	if (!btf_record_has_field(rec, BPF_UPTR))
198 		return 0;
199 
200 	for (i = 0, field = rec->fields; i < rec->cnt; i++, field++) {
201 		if (field->type != BPF_UPTR)
202 			continue;
203 
204 		uptr_addr = obj + field->offset;
205 		start = *(unsigned long *)uptr_addr;
206 		if (!start)
207 			continue;
208 
209 		t = btf_type_by_id(field->kptr.btf, field->kptr.btf_id);
210 		/* t->size was checked for zero before */
211 		if (check_add_overflow(start, t->size - 1, &end)) {
212 			err = -EFAULT;
213 			goto unpin_all;
214 		}
215 
216 		/* The uptr's struct cannot span across two pages */
217 		if ((start & PAGE_MASK) != (end & PAGE_MASK)) {
218 			err = -EOPNOTSUPP;
219 			goto unpin_all;
220 		}
221 
222 		err = pin_user_pages_fast(start, 1, FOLL_LONGTERM | FOLL_WRITE, &page);
223 		if (err != 1)
224 			goto unpin_all;
225 
226 		if (PageHighMem(page)) {
227 			err = -EOPNOTSUPP;
228 			unpin_user_page(page);
229 			goto unpin_all;
230 		}
231 
232 		*uptr_addr = page_address(page) + offset_in_page(start);
233 	}
234 
235 	return 0;
236 
237 unpin_all:
238 	__bpf_obj_unpin_uptrs(rec, i, obj);
239 	return err;
240 }
241 
242 static int bpf_map_update_value(struct bpf_map *map, struct file *map_file,
243 				void *key, void *value, __u64 flags)
244 {
245 	int err;
246 
247 	/* Need to create a kthread, thus must support schedule */
248 	if (bpf_map_is_offloaded(map)) {
249 		return bpf_map_offload_update_elem(map, key, value, flags);
250 	} else if (map->map_type == BPF_MAP_TYPE_CPUMAP ||
251 		   map->map_type == BPF_MAP_TYPE_ARENA ||
252 		   map->map_type == BPF_MAP_TYPE_STRUCT_OPS) {
253 		return map->ops->map_update_elem(map, key, value, flags);
254 	} else if (map->map_type == BPF_MAP_TYPE_SOCKHASH ||
255 		   map->map_type == BPF_MAP_TYPE_SOCKMAP) {
256 		return sock_map_update_elem_sys(map, key, value, flags);
257 	} else if (IS_FD_PROG_ARRAY(map)) {
258 		return bpf_fd_array_map_update_elem(map, map_file, key, value,
259 						    flags);
260 	}
261 
262 	bpf_disable_instrumentation();
263 	if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
264 	    map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
265 		err = bpf_percpu_hash_update(map, key, value, flags);
266 	} else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) {
267 		err = bpf_percpu_array_update(map, key, value, flags);
268 	} else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) {
269 		err = bpf_percpu_cgroup_storage_update(map, key, value,
270 						       flags);
271 	} else if (IS_FD_ARRAY(map)) {
272 		err = bpf_fd_array_map_update_elem(map, map_file, key, value,
273 						   flags);
274 	} else if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) {
275 		err = bpf_fd_htab_map_update_elem(map, map_file, key, value,
276 						  flags);
277 	} else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) {
278 		/* rcu_read_lock() is not needed */
279 		err = bpf_fd_reuseport_array_update_elem(map, key, value,
280 							 flags);
281 	} else if (map->map_type == BPF_MAP_TYPE_QUEUE ||
282 		   map->map_type == BPF_MAP_TYPE_STACK ||
283 		   map->map_type == BPF_MAP_TYPE_BLOOM_FILTER) {
284 		err = map->ops->map_push_elem(map, value, flags);
285 	} else {
286 		err = bpf_obj_pin_uptrs(map->record, value);
287 		if (!err) {
288 			rcu_read_lock();
289 			err = map->ops->map_update_elem(map, key, value, flags);
290 			rcu_read_unlock();
291 			if (err)
292 				bpf_obj_unpin_uptrs(map->record, value);
293 		}
294 	}
295 	bpf_enable_instrumentation();
296 
297 	return err;
298 }
299 
300 static int bpf_map_copy_value(struct bpf_map *map, void *key, void *value,
301 			      __u64 flags)
302 {
303 	void *ptr;
304 	int err;
305 
306 	if (bpf_map_is_offloaded(map))
307 		return bpf_map_offload_lookup_elem(map, key, value);
308 
309 	bpf_disable_instrumentation();
310 	if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
311 	    map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
312 		err = bpf_percpu_hash_copy(map, key, value);
313 	} else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) {
314 		err = bpf_percpu_array_copy(map, key, value);
315 	} else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) {
316 		err = bpf_percpu_cgroup_storage_copy(map, key, value);
317 	} else if (map->map_type == BPF_MAP_TYPE_STACK_TRACE) {
318 		err = bpf_stackmap_copy(map, key, value);
319 	} else if (IS_FD_ARRAY(map) || IS_FD_PROG_ARRAY(map)) {
320 		err = bpf_fd_array_map_lookup_elem(map, key, value);
321 	} else if (IS_FD_HASH(map)) {
322 		err = bpf_fd_htab_map_lookup_elem(map, key, value);
323 	} else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) {
324 		err = bpf_fd_reuseport_array_lookup_elem(map, key, value);
325 	} else if (map->map_type == BPF_MAP_TYPE_QUEUE ||
326 		   map->map_type == BPF_MAP_TYPE_STACK ||
327 		   map->map_type == BPF_MAP_TYPE_BLOOM_FILTER) {
328 		err = map->ops->map_peek_elem(map, value);
329 	} else if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS) {
330 		/* struct_ops map requires directly updating "value" */
331 		err = bpf_struct_ops_map_sys_lookup_elem(map, key, value);
332 	} else {
333 		rcu_read_lock();
334 		if (map->ops->map_lookup_elem_sys_only)
335 			ptr = map->ops->map_lookup_elem_sys_only(map, key);
336 		else
337 			ptr = map->ops->map_lookup_elem(map, key);
338 		if (IS_ERR(ptr)) {
339 			err = PTR_ERR(ptr);
340 		} else if (!ptr) {
341 			err = -ENOENT;
342 		} else {
343 			err = 0;
344 			if (flags & BPF_F_LOCK)
345 				/* lock 'ptr' and copy everything but lock */
346 				copy_map_value_locked(map, value, ptr, true);
347 			else
348 				copy_map_value(map, value, ptr);
349 			/* mask lock and timer, since value wasn't zero inited */
350 			check_and_init_map_value(map, value);
351 		}
352 		rcu_read_unlock();
353 	}
354 
355 	bpf_enable_instrumentation();
356 
357 	return err;
358 }
359 
360 /* Please, do not use this function outside from the map creation path
361  * (e.g. in map update path) without taking care of setting the active
362  * memory cgroup (see at bpf_map_kmalloc_node() for example).
363  */
364 static void *__bpf_map_area_alloc(u64 size, int numa_node, bool mmapable)
365 {
366 	/* We really just want to fail instead of triggering OOM killer
367 	 * under memory pressure, therefore we set __GFP_NORETRY to kmalloc,
368 	 * which is used for lower order allocation requests.
369 	 *
370 	 * It has been observed that higher order allocation requests done by
371 	 * vmalloc with __GFP_NORETRY being set might fail due to not trying
372 	 * to reclaim memory from the page cache, thus we set
373 	 * __GFP_RETRY_MAYFAIL to avoid such situations.
374 	 */
375 
376 	gfp_t gfp = bpf_memcg_flags(__GFP_NOWARN | __GFP_ZERO);
377 	unsigned int flags = 0;
378 	unsigned long align = 1;
379 	void *area;
380 
381 	if (size >= SIZE_MAX)
382 		return NULL;
383 
384 	/* kmalloc()'ed memory can't be mmap()'ed */
385 	if (mmapable) {
386 		BUG_ON(!PAGE_ALIGNED(size));
387 		align = SHMLBA;
388 		flags = VM_USERMAP;
389 	} else if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) {
390 		area = kmalloc_node(size, gfp | GFP_USER | __GFP_NORETRY,
391 				    numa_node);
392 		if (area != NULL)
393 			return area;
394 	}
395 
396 	return __vmalloc_node_range(size, align, VMALLOC_START, VMALLOC_END,
397 			gfp | GFP_KERNEL | __GFP_RETRY_MAYFAIL, PAGE_KERNEL,
398 			flags, numa_node, __builtin_return_address(0));
399 }
400 
401 void *bpf_map_area_alloc(u64 size, int numa_node)
402 {
403 	return __bpf_map_area_alloc(size, numa_node, false);
404 }
405 
406 void *bpf_map_area_mmapable_alloc(u64 size, int numa_node)
407 {
408 	return __bpf_map_area_alloc(size, numa_node, true);
409 }
410 
411 void bpf_map_area_free(void *area)
412 {
413 	kvfree(area);
414 }
415 
416 static u32 bpf_map_flags_retain_permanent(u32 flags)
417 {
418 	/* Some map creation flags are not tied to the map object but
419 	 * rather to the map fd instead, so they have no meaning upon
420 	 * map object inspection since multiple file descriptors with
421 	 * different (access) properties can exist here. Thus, given
422 	 * this has zero meaning for the map itself, lets clear these
423 	 * from here.
424 	 */
425 	return flags & ~(BPF_F_RDONLY | BPF_F_WRONLY);
426 }
427 
428 void bpf_map_init_from_attr(struct bpf_map *map, union bpf_attr *attr)
429 {
430 	map->map_type = attr->map_type;
431 	map->key_size = attr->key_size;
432 	map->value_size = attr->value_size;
433 	map->max_entries = attr->max_entries;
434 	map->map_flags = bpf_map_flags_retain_permanent(attr->map_flags);
435 	map->numa_node = bpf_map_attr_numa_node(attr);
436 	map->map_extra = attr->map_extra;
437 }
438 
439 static int bpf_map_alloc_id(struct bpf_map *map)
440 {
441 	int id;
442 
443 	idr_preload(GFP_KERNEL);
444 	spin_lock_bh(&map_idr_lock);
445 	id = idr_alloc_cyclic(&map_idr, map, 1, INT_MAX, GFP_ATOMIC);
446 	if (id > 0)
447 		map->id = id;
448 	spin_unlock_bh(&map_idr_lock);
449 	idr_preload_end();
450 
451 	if (WARN_ON_ONCE(!id))
452 		return -ENOSPC;
453 
454 	return id > 0 ? 0 : id;
455 }
456 
457 void bpf_map_free_id(struct bpf_map *map)
458 {
459 	unsigned long flags;
460 
461 	/* Offloaded maps are removed from the IDR store when their device
462 	 * disappears - even if someone holds an fd to them they are unusable,
463 	 * the memory is gone, all ops will fail; they are simply waiting for
464 	 * refcnt to drop to be freed.
465 	 */
466 	if (!map->id)
467 		return;
468 
469 	spin_lock_irqsave(&map_idr_lock, flags);
470 
471 	idr_remove(&map_idr, map->id);
472 	map->id = 0;
473 
474 	spin_unlock_irqrestore(&map_idr_lock, flags);
475 }
476 
477 #ifdef CONFIG_MEMCG
478 static void bpf_map_save_memcg(struct bpf_map *map)
479 {
480 	/* Currently if a map is created by a process belonging to the root
481 	 * memory cgroup, get_obj_cgroup_from_current() will return NULL.
482 	 * So we have to check map->objcg for being NULL each time it's
483 	 * being used.
484 	 */
485 	if (memcg_bpf_enabled())
486 		map->objcg = get_obj_cgroup_from_current();
487 }
488 
489 static void bpf_map_release_memcg(struct bpf_map *map)
490 {
491 	if (map->objcg)
492 		obj_cgroup_put(map->objcg);
493 }
494 
495 static struct mem_cgroup *bpf_map_get_memcg(const struct bpf_map *map)
496 {
497 	if (map->objcg)
498 		return get_mem_cgroup_from_objcg(map->objcg);
499 
500 	return root_mem_cgroup;
501 }
502 
503 void *bpf_map_kmalloc_node(const struct bpf_map *map, size_t size, gfp_t flags,
504 			   int node)
505 {
506 	struct mem_cgroup *memcg, *old_memcg;
507 	void *ptr;
508 
509 	memcg = bpf_map_get_memcg(map);
510 	old_memcg = set_active_memcg(memcg);
511 	ptr = kmalloc_node(size, flags | __GFP_ACCOUNT, node);
512 	set_active_memcg(old_memcg);
513 	mem_cgroup_put(memcg);
514 
515 	return ptr;
516 }
517 
518 void *bpf_map_kzalloc(const struct bpf_map *map, size_t size, gfp_t flags)
519 {
520 	struct mem_cgroup *memcg, *old_memcg;
521 	void *ptr;
522 
523 	memcg = bpf_map_get_memcg(map);
524 	old_memcg = set_active_memcg(memcg);
525 	ptr = kzalloc(size, flags | __GFP_ACCOUNT);
526 	set_active_memcg(old_memcg);
527 	mem_cgroup_put(memcg);
528 
529 	return ptr;
530 }
531 
532 void *bpf_map_kvcalloc(struct bpf_map *map, size_t n, size_t size,
533 		       gfp_t flags)
534 {
535 	struct mem_cgroup *memcg, *old_memcg;
536 	void *ptr;
537 
538 	memcg = bpf_map_get_memcg(map);
539 	old_memcg = set_active_memcg(memcg);
540 	ptr = kvcalloc(n, size, flags | __GFP_ACCOUNT);
541 	set_active_memcg(old_memcg);
542 	mem_cgroup_put(memcg);
543 
544 	return ptr;
545 }
546 
547 void __percpu *bpf_map_alloc_percpu(const struct bpf_map *map, size_t size,
548 				    size_t align, gfp_t flags)
549 {
550 	struct mem_cgroup *memcg, *old_memcg;
551 	void __percpu *ptr;
552 
553 	memcg = bpf_map_get_memcg(map);
554 	old_memcg = set_active_memcg(memcg);
555 	ptr = __alloc_percpu_gfp(size, align, flags | __GFP_ACCOUNT);
556 	set_active_memcg(old_memcg);
557 	mem_cgroup_put(memcg);
558 
559 	return ptr;
560 }
561 
562 #else
563 static void bpf_map_save_memcg(struct bpf_map *map)
564 {
565 }
566 
567 static void bpf_map_release_memcg(struct bpf_map *map)
568 {
569 }
570 #endif
571 
572 int bpf_map_alloc_pages(const struct bpf_map *map, gfp_t gfp, int nid,
573 			unsigned long nr_pages, struct page **pages)
574 {
575 	unsigned long i, j;
576 	struct page *pg;
577 	int ret = 0;
578 #ifdef CONFIG_MEMCG
579 	struct mem_cgroup *memcg, *old_memcg;
580 
581 	memcg = bpf_map_get_memcg(map);
582 	old_memcg = set_active_memcg(memcg);
583 #endif
584 	for (i = 0; i < nr_pages; i++) {
585 		pg = alloc_pages_node(nid, gfp | __GFP_ACCOUNT, 0);
586 
587 		if (pg) {
588 			pages[i] = pg;
589 			continue;
590 		}
591 		for (j = 0; j < i; j++)
592 			__free_page(pages[j]);
593 		ret = -ENOMEM;
594 		break;
595 	}
596 
597 #ifdef CONFIG_MEMCG
598 	set_active_memcg(old_memcg);
599 	mem_cgroup_put(memcg);
600 #endif
601 	return ret;
602 }
603 
604 
605 static int btf_field_cmp(const void *a, const void *b)
606 {
607 	const struct btf_field *f1 = a, *f2 = b;
608 
609 	if (f1->offset < f2->offset)
610 		return -1;
611 	else if (f1->offset > f2->offset)
612 		return 1;
613 	return 0;
614 }
615 
616 struct btf_field *btf_record_find(const struct btf_record *rec, u32 offset,
617 				  u32 field_mask)
618 {
619 	struct btf_field *field;
620 
621 	if (IS_ERR_OR_NULL(rec) || !(rec->field_mask & field_mask))
622 		return NULL;
623 	field = bsearch(&offset, rec->fields, rec->cnt, sizeof(rec->fields[0]), btf_field_cmp);
624 	if (!field || !(field->type & field_mask))
625 		return NULL;
626 	return field;
627 }
628 
629 void btf_record_free(struct btf_record *rec)
630 {
631 	int i;
632 
633 	if (IS_ERR_OR_NULL(rec))
634 		return;
635 	for (i = 0; i < rec->cnt; i++) {
636 		switch (rec->fields[i].type) {
637 		case BPF_KPTR_UNREF:
638 		case BPF_KPTR_REF:
639 		case BPF_KPTR_PERCPU:
640 		case BPF_UPTR:
641 			if (rec->fields[i].kptr.module)
642 				module_put(rec->fields[i].kptr.module);
643 			if (btf_is_kernel(rec->fields[i].kptr.btf))
644 				btf_put(rec->fields[i].kptr.btf);
645 			break;
646 		case BPF_LIST_HEAD:
647 		case BPF_LIST_NODE:
648 		case BPF_RB_ROOT:
649 		case BPF_RB_NODE:
650 		case BPF_SPIN_LOCK:
651 		case BPF_TIMER:
652 		case BPF_REFCOUNT:
653 		case BPF_WORKQUEUE:
654 			/* Nothing to release */
655 			break;
656 		default:
657 			WARN_ON_ONCE(1);
658 			continue;
659 		}
660 	}
661 	kfree(rec);
662 }
663 
664 void bpf_map_free_record(struct bpf_map *map)
665 {
666 	btf_record_free(map->record);
667 	map->record = NULL;
668 }
669 
670 struct btf_record *btf_record_dup(const struct btf_record *rec)
671 {
672 	const struct btf_field *fields;
673 	struct btf_record *new_rec;
674 	int ret, size, i;
675 
676 	if (IS_ERR_OR_NULL(rec))
677 		return NULL;
678 	size = offsetof(struct btf_record, fields[rec->cnt]);
679 	new_rec = kmemdup(rec, size, GFP_KERNEL | __GFP_NOWARN);
680 	if (!new_rec)
681 		return ERR_PTR(-ENOMEM);
682 	/* Do a deep copy of the btf_record */
683 	fields = rec->fields;
684 	new_rec->cnt = 0;
685 	for (i = 0; i < rec->cnt; i++) {
686 		switch (fields[i].type) {
687 		case BPF_KPTR_UNREF:
688 		case BPF_KPTR_REF:
689 		case BPF_KPTR_PERCPU:
690 		case BPF_UPTR:
691 			if (btf_is_kernel(fields[i].kptr.btf))
692 				btf_get(fields[i].kptr.btf);
693 			if (fields[i].kptr.module && !try_module_get(fields[i].kptr.module)) {
694 				ret = -ENXIO;
695 				goto free;
696 			}
697 			break;
698 		case BPF_LIST_HEAD:
699 		case BPF_LIST_NODE:
700 		case BPF_RB_ROOT:
701 		case BPF_RB_NODE:
702 		case BPF_SPIN_LOCK:
703 		case BPF_TIMER:
704 		case BPF_REFCOUNT:
705 		case BPF_WORKQUEUE:
706 			/* Nothing to acquire */
707 			break;
708 		default:
709 			ret = -EFAULT;
710 			WARN_ON_ONCE(1);
711 			goto free;
712 		}
713 		new_rec->cnt++;
714 	}
715 	return new_rec;
716 free:
717 	btf_record_free(new_rec);
718 	return ERR_PTR(ret);
719 }
720 
721 bool btf_record_equal(const struct btf_record *rec_a, const struct btf_record *rec_b)
722 {
723 	bool a_has_fields = !IS_ERR_OR_NULL(rec_a), b_has_fields = !IS_ERR_OR_NULL(rec_b);
724 	int size;
725 
726 	if (!a_has_fields && !b_has_fields)
727 		return true;
728 	if (a_has_fields != b_has_fields)
729 		return false;
730 	if (rec_a->cnt != rec_b->cnt)
731 		return false;
732 	size = offsetof(struct btf_record, fields[rec_a->cnt]);
733 	/* btf_parse_fields uses kzalloc to allocate a btf_record, so unused
734 	 * members are zeroed out. So memcmp is safe to do without worrying
735 	 * about padding/unused fields.
736 	 *
737 	 * While spin_lock, timer, and kptr have no relation to map BTF,
738 	 * list_head metadata is specific to map BTF, the btf and value_rec
739 	 * members in particular. btf is the map BTF, while value_rec points to
740 	 * btf_record in that map BTF.
741 	 *
742 	 * So while by default, we don't rely on the map BTF (which the records
743 	 * were parsed from) matching for both records, which is not backwards
744 	 * compatible, in case list_head is part of it, we implicitly rely on
745 	 * that by way of depending on memcmp succeeding for it.
746 	 */
747 	return !memcmp(rec_a, rec_b, size);
748 }
749 
750 void bpf_obj_free_timer(const struct btf_record *rec, void *obj)
751 {
752 	if (WARN_ON_ONCE(!btf_record_has_field(rec, BPF_TIMER)))
753 		return;
754 	bpf_timer_cancel_and_free(obj + rec->timer_off);
755 }
756 
757 void bpf_obj_free_workqueue(const struct btf_record *rec, void *obj)
758 {
759 	if (WARN_ON_ONCE(!btf_record_has_field(rec, BPF_WORKQUEUE)))
760 		return;
761 	bpf_wq_cancel_and_free(obj + rec->wq_off);
762 }
763 
764 void bpf_obj_free_fields(const struct btf_record *rec, void *obj)
765 {
766 	const struct btf_field *fields;
767 	int i;
768 
769 	if (IS_ERR_OR_NULL(rec))
770 		return;
771 	fields = rec->fields;
772 	for (i = 0; i < rec->cnt; i++) {
773 		struct btf_struct_meta *pointee_struct_meta;
774 		const struct btf_field *field = &fields[i];
775 		void *field_ptr = obj + field->offset;
776 		void *xchgd_field;
777 
778 		switch (fields[i].type) {
779 		case BPF_SPIN_LOCK:
780 			break;
781 		case BPF_TIMER:
782 			bpf_timer_cancel_and_free(field_ptr);
783 			break;
784 		case BPF_WORKQUEUE:
785 			bpf_wq_cancel_and_free(field_ptr);
786 			break;
787 		case BPF_KPTR_UNREF:
788 			WRITE_ONCE(*(u64 *)field_ptr, 0);
789 			break;
790 		case BPF_KPTR_REF:
791 		case BPF_KPTR_PERCPU:
792 			xchgd_field = (void *)xchg((unsigned long *)field_ptr, 0);
793 			if (!xchgd_field)
794 				break;
795 
796 			if (!btf_is_kernel(field->kptr.btf)) {
797 				pointee_struct_meta = btf_find_struct_meta(field->kptr.btf,
798 									   field->kptr.btf_id);
799 				migrate_disable();
800 				__bpf_obj_drop_impl(xchgd_field, pointee_struct_meta ?
801 								 pointee_struct_meta->record : NULL,
802 								 fields[i].type == BPF_KPTR_PERCPU);
803 				migrate_enable();
804 			} else {
805 				field->kptr.dtor(xchgd_field);
806 			}
807 			break;
808 		case BPF_UPTR:
809 			/* The caller ensured that no one is using the uptr */
810 			unpin_uptr_kaddr(*(void **)field_ptr);
811 			break;
812 		case BPF_LIST_HEAD:
813 			if (WARN_ON_ONCE(rec->spin_lock_off < 0))
814 				continue;
815 			bpf_list_head_free(field, field_ptr, obj + rec->spin_lock_off);
816 			break;
817 		case BPF_RB_ROOT:
818 			if (WARN_ON_ONCE(rec->spin_lock_off < 0))
819 				continue;
820 			bpf_rb_root_free(field, field_ptr, obj + rec->spin_lock_off);
821 			break;
822 		case BPF_LIST_NODE:
823 		case BPF_RB_NODE:
824 		case BPF_REFCOUNT:
825 			break;
826 		default:
827 			WARN_ON_ONCE(1);
828 			continue;
829 		}
830 	}
831 }
832 
833 static void bpf_map_free(struct bpf_map *map)
834 {
835 	struct btf_record *rec = map->record;
836 	struct btf *btf = map->btf;
837 
838 	/* implementation dependent freeing */
839 	map->ops->map_free(map);
840 	/* Delay freeing of btf_record for maps, as map_free
841 	 * callback usually needs access to them. It is better to do it here
842 	 * than require each callback to do the free itself manually.
843 	 *
844 	 * Note that the btf_record stashed in map->inner_map_meta->record was
845 	 * already freed using the map_free callback for map in map case which
846 	 * eventually calls bpf_map_free_meta, since inner_map_meta is only a
847 	 * template bpf_map struct used during verification.
848 	 */
849 	btf_record_free(rec);
850 	/* Delay freeing of btf for maps, as map_free callback may need
851 	 * struct_meta info which will be freed with btf_put().
852 	 */
853 	btf_put(btf);
854 }
855 
856 /* called from workqueue */
857 static void bpf_map_free_deferred(struct work_struct *work)
858 {
859 	struct bpf_map *map = container_of(work, struct bpf_map, work);
860 
861 	security_bpf_map_free(map);
862 	bpf_map_release_memcg(map);
863 	bpf_map_free(map);
864 }
865 
866 static void bpf_map_put_uref(struct bpf_map *map)
867 {
868 	if (atomic64_dec_and_test(&map->usercnt)) {
869 		if (map->ops->map_release_uref)
870 			map->ops->map_release_uref(map);
871 	}
872 }
873 
874 static void bpf_map_free_in_work(struct bpf_map *map)
875 {
876 	INIT_WORK(&map->work, bpf_map_free_deferred);
877 	/* Avoid spawning kworkers, since they all might contend
878 	 * for the same mutex like slab_mutex.
879 	 */
880 	queue_work(system_unbound_wq, &map->work);
881 }
882 
883 static void bpf_map_free_rcu_gp(struct rcu_head *rcu)
884 {
885 	bpf_map_free_in_work(container_of(rcu, struct bpf_map, rcu));
886 }
887 
888 static void bpf_map_free_mult_rcu_gp(struct rcu_head *rcu)
889 {
890 	if (rcu_trace_implies_rcu_gp())
891 		bpf_map_free_rcu_gp(rcu);
892 	else
893 		call_rcu(rcu, bpf_map_free_rcu_gp);
894 }
895 
896 /* decrement map refcnt and schedule it for freeing via workqueue
897  * (underlying map implementation ops->map_free() might sleep)
898  */
899 void bpf_map_put(struct bpf_map *map)
900 {
901 	if (atomic64_dec_and_test(&map->refcnt)) {
902 		/* bpf_map_free_id() must be called first */
903 		bpf_map_free_id(map);
904 
905 		WARN_ON_ONCE(atomic64_read(&map->sleepable_refcnt));
906 		if (READ_ONCE(map->free_after_mult_rcu_gp))
907 			call_rcu_tasks_trace(&map->rcu, bpf_map_free_mult_rcu_gp);
908 		else if (READ_ONCE(map->free_after_rcu_gp))
909 			call_rcu(&map->rcu, bpf_map_free_rcu_gp);
910 		else
911 			bpf_map_free_in_work(map);
912 	}
913 }
914 EXPORT_SYMBOL_GPL(bpf_map_put);
915 
916 void bpf_map_put_with_uref(struct bpf_map *map)
917 {
918 	bpf_map_put_uref(map);
919 	bpf_map_put(map);
920 }
921 
922 static int bpf_map_release(struct inode *inode, struct file *filp)
923 {
924 	struct bpf_map *map = filp->private_data;
925 
926 	if (map->ops->map_release)
927 		map->ops->map_release(map, filp);
928 
929 	bpf_map_put_with_uref(map);
930 	return 0;
931 }
932 
933 static fmode_t map_get_sys_perms(struct bpf_map *map, struct fd f)
934 {
935 	fmode_t mode = fd_file(f)->f_mode;
936 
937 	/* Our file permissions may have been overridden by global
938 	 * map permissions facing syscall side.
939 	 */
940 	if (READ_ONCE(map->frozen))
941 		mode &= ~FMODE_CAN_WRITE;
942 	return mode;
943 }
944 
945 #ifdef CONFIG_PROC_FS
946 /* Show the memory usage of a bpf map */
947 static u64 bpf_map_memory_usage(const struct bpf_map *map)
948 {
949 	return map->ops->map_mem_usage(map);
950 }
951 
952 static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp)
953 {
954 	struct bpf_map *map = filp->private_data;
955 	u32 type = 0, jited = 0;
956 
957 	if (map_type_contains_progs(map)) {
958 		spin_lock(&map->owner.lock);
959 		type  = map->owner.type;
960 		jited = map->owner.jited;
961 		spin_unlock(&map->owner.lock);
962 	}
963 
964 	seq_printf(m,
965 		   "map_type:\t%u\n"
966 		   "key_size:\t%u\n"
967 		   "value_size:\t%u\n"
968 		   "max_entries:\t%u\n"
969 		   "map_flags:\t%#x\n"
970 		   "map_extra:\t%#llx\n"
971 		   "memlock:\t%llu\n"
972 		   "map_id:\t%u\n"
973 		   "frozen:\t%u\n",
974 		   map->map_type,
975 		   map->key_size,
976 		   map->value_size,
977 		   map->max_entries,
978 		   map->map_flags,
979 		   (unsigned long long)map->map_extra,
980 		   bpf_map_memory_usage(map),
981 		   map->id,
982 		   READ_ONCE(map->frozen));
983 	if (type) {
984 		seq_printf(m, "owner_prog_type:\t%u\n", type);
985 		seq_printf(m, "owner_jited:\t%u\n", jited);
986 	}
987 }
988 #endif
989 
990 static ssize_t bpf_dummy_read(struct file *filp, char __user *buf, size_t siz,
991 			      loff_t *ppos)
992 {
993 	/* We need this handler such that alloc_file() enables
994 	 * f_mode with FMODE_CAN_READ.
995 	 */
996 	return -EINVAL;
997 }
998 
999 static ssize_t bpf_dummy_write(struct file *filp, const char __user *buf,
1000 			       size_t siz, loff_t *ppos)
1001 {
1002 	/* We need this handler such that alloc_file() enables
1003 	 * f_mode with FMODE_CAN_WRITE.
1004 	 */
1005 	return -EINVAL;
1006 }
1007 
1008 /* called for any extra memory-mapped regions (except initial) */
1009 static void bpf_map_mmap_open(struct vm_area_struct *vma)
1010 {
1011 	struct bpf_map *map = vma->vm_file->private_data;
1012 
1013 	if (vma->vm_flags & VM_MAYWRITE)
1014 		bpf_map_write_active_inc(map);
1015 }
1016 
1017 /* called for all unmapped memory region (including initial) */
1018 static void bpf_map_mmap_close(struct vm_area_struct *vma)
1019 {
1020 	struct bpf_map *map = vma->vm_file->private_data;
1021 
1022 	if (vma->vm_flags & VM_MAYWRITE)
1023 		bpf_map_write_active_dec(map);
1024 }
1025 
1026 static const struct vm_operations_struct bpf_map_default_vmops = {
1027 	.open		= bpf_map_mmap_open,
1028 	.close		= bpf_map_mmap_close,
1029 };
1030 
1031 static int bpf_map_mmap(struct file *filp, struct vm_area_struct *vma)
1032 {
1033 	struct bpf_map *map = filp->private_data;
1034 	int err;
1035 
1036 	if (!map->ops->map_mmap || !IS_ERR_OR_NULL(map->record))
1037 		return -ENOTSUPP;
1038 
1039 	if (!(vma->vm_flags & VM_SHARED))
1040 		return -EINVAL;
1041 
1042 	mutex_lock(&map->freeze_mutex);
1043 
1044 	if (vma->vm_flags & VM_WRITE) {
1045 		if (map->frozen) {
1046 			err = -EPERM;
1047 			goto out;
1048 		}
1049 		/* map is meant to be read-only, so do not allow mapping as
1050 		 * writable, because it's possible to leak a writable page
1051 		 * reference and allows user-space to still modify it after
1052 		 * freezing, while verifier will assume contents do not change
1053 		 */
1054 		if (map->map_flags & BPF_F_RDONLY_PROG) {
1055 			err = -EACCES;
1056 			goto out;
1057 		}
1058 	}
1059 
1060 	/* set default open/close callbacks */
1061 	vma->vm_ops = &bpf_map_default_vmops;
1062 	vma->vm_private_data = map;
1063 	vm_flags_clear(vma, VM_MAYEXEC);
1064 	if (!(vma->vm_flags & VM_WRITE))
1065 		/* disallow re-mapping with PROT_WRITE */
1066 		vm_flags_clear(vma, VM_MAYWRITE);
1067 
1068 	err = map->ops->map_mmap(map, vma);
1069 	if (err)
1070 		goto out;
1071 
1072 	if (vma->vm_flags & VM_MAYWRITE)
1073 		bpf_map_write_active_inc(map);
1074 out:
1075 	mutex_unlock(&map->freeze_mutex);
1076 	return err;
1077 }
1078 
1079 static __poll_t bpf_map_poll(struct file *filp, struct poll_table_struct *pts)
1080 {
1081 	struct bpf_map *map = filp->private_data;
1082 
1083 	if (map->ops->map_poll)
1084 		return map->ops->map_poll(map, filp, pts);
1085 
1086 	return EPOLLERR;
1087 }
1088 
1089 static unsigned long bpf_get_unmapped_area(struct file *filp, unsigned long addr,
1090 					   unsigned long len, unsigned long pgoff,
1091 					   unsigned long flags)
1092 {
1093 	struct bpf_map *map = filp->private_data;
1094 
1095 	if (map->ops->map_get_unmapped_area)
1096 		return map->ops->map_get_unmapped_area(filp, addr, len, pgoff, flags);
1097 #ifdef CONFIG_MMU
1098 	return mm_get_unmapped_area(current->mm, filp, addr, len, pgoff, flags);
1099 #else
1100 	return addr;
1101 #endif
1102 }
1103 
1104 const struct file_operations bpf_map_fops = {
1105 #ifdef CONFIG_PROC_FS
1106 	.show_fdinfo	= bpf_map_show_fdinfo,
1107 #endif
1108 	.release	= bpf_map_release,
1109 	.read		= bpf_dummy_read,
1110 	.write		= bpf_dummy_write,
1111 	.mmap		= bpf_map_mmap,
1112 	.poll		= bpf_map_poll,
1113 	.get_unmapped_area = bpf_get_unmapped_area,
1114 };
1115 
1116 int bpf_map_new_fd(struct bpf_map *map, int flags)
1117 {
1118 	int ret;
1119 
1120 	ret = security_bpf_map(map, OPEN_FMODE(flags));
1121 	if (ret < 0)
1122 		return ret;
1123 
1124 	return anon_inode_getfd("bpf-map", &bpf_map_fops, map,
1125 				flags | O_CLOEXEC);
1126 }
1127 
1128 int bpf_get_file_flag(int flags)
1129 {
1130 	if ((flags & BPF_F_RDONLY) && (flags & BPF_F_WRONLY))
1131 		return -EINVAL;
1132 	if (flags & BPF_F_RDONLY)
1133 		return O_RDONLY;
1134 	if (flags & BPF_F_WRONLY)
1135 		return O_WRONLY;
1136 	return O_RDWR;
1137 }
1138 
1139 /* helper macro to check that unused fields 'union bpf_attr' are zero */
1140 #define CHECK_ATTR(CMD) \
1141 	memchr_inv((void *) &attr->CMD##_LAST_FIELD + \
1142 		   sizeof(attr->CMD##_LAST_FIELD), 0, \
1143 		   sizeof(*attr) - \
1144 		   offsetof(union bpf_attr, CMD##_LAST_FIELD) - \
1145 		   sizeof(attr->CMD##_LAST_FIELD)) != NULL
1146 
1147 /* dst and src must have at least "size" number of bytes.
1148  * Return strlen on success and < 0 on error.
1149  */
1150 int bpf_obj_name_cpy(char *dst, const char *src, unsigned int size)
1151 {
1152 	const char *end = src + size;
1153 	const char *orig_src = src;
1154 
1155 	memset(dst, 0, size);
1156 	/* Copy all isalnum(), '_' and '.' chars. */
1157 	while (src < end && *src) {
1158 		if (!isalnum(*src) &&
1159 		    *src != '_' && *src != '.')
1160 			return -EINVAL;
1161 		*dst++ = *src++;
1162 	}
1163 
1164 	/* No '\0' found in "size" number of bytes */
1165 	if (src == end)
1166 		return -EINVAL;
1167 
1168 	return src - orig_src;
1169 }
1170 
1171 int map_check_no_btf(const struct bpf_map *map,
1172 		     const struct btf *btf,
1173 		     const struct btf_type *key_type,
1174 		     const struct btf_type *value_type)
1175 {
1176 	return -ENOTSUPP;
1177 }
1178 
1179 static int map_check_btf(struct bpf_map *map, struct bpf_token *token,
1180 			 const struct btf *btf, u32 btf_key_id, u32 btf_value_id)
1181 {
1182 	const struct btf_type *key_type, *value_type;
1183 	u32 key_size, value_size;
1184 	int ret = 0;
1185 
1186 	/* Some maps allow key to be unspecified. */
1187 	if (btf_key_id) {
1188 		key_type = btf_type_id_size(btf, &btf_key_id, &key_size);
1189 		if (!key_type || key_size != map->key_size)
1190 			return -EINVAL;
1191 	} else {
1192 		key_type = btf_type_by_id(btf, 0);
1193 		if (!map->ops->map_check_btf)
1194 			return -EINVAL;
1195 	}
1196 
1197 	value_type = btf_type_id_size(btf, &btf_value_id, &value_size);
1198 	if (!value_type || value_size != map->value_size)
1199 		return -EINVAL;
1200 
1201 	map->record = btf_parse_fields(btf, value_type,
1202 				       BPF_SPIN_LOCK | BPF_TIMER | BPF_KPTR | BPF_LIST_HEAD |
1203 				       BPF_RB_ROOT | BPF_REFCOUNT | BPF_WORKQUEUE | BPF_UPTR,
1204 				       map->value_size);
1205 	if (!IS_ERR_OR_NULL(map->record)) {
1206 		int i;
1207 
1208 		if (!bpf_token_capable(token, CAP_BPF)) {
1209 			ret = -EPERM;
1210 			goto free_map_tab;
1211 		}
1212 		if (map->map_flags & (BPF_F_RDONLY_PROG | BPF_F_WRONLY_PROG)) {
1213 			ret = -EACCES;
1214 			goto free_map_tab;
1215 		}
1216 		for (i = 0; i < sizeof(map->record->field_mask) * 8; i++) {
1217 			switch (map->record->field_mask & (1 << i)) {
1218 			case 0:
1219 				continue;
1220 			case BPF_SPIN_LOCK:
1221 				if (map->map_type != BPF_MAP_TYPE_HASH &&
1222 				    map->map_type != BPF_MAP_TYPE_ARRAY &&
1223 				    map->map_type != BPF_MAP_TYPE_CGROUP_STORAGE &&
1224 				    map->map_type != BPF_MAP_TYPE_SK_STORAGE &&
1225 				    map->map_type != BPF_MAP_TYPE_INODE_STORAGE &&
1226 				    map->map_type != BPF_MAP_TYPE_TASK_STORAGE &&
1227 				    map->map_type != BPF_MAP_TYPE_CGRP_STORAGE) {
1228 					ret = -EOPNOTSUPP;
1229 					goto free_map_tab;
1230 				}
1231 				break;
1232 			case BPF_TIMER:
1233 			case BPF_WORKQUEUE:
1234 				if (map->map_type != BPF_MAP_TYPE_HASH &&
1235 				    map->map_type != BPF_MAP_TYPE_LRU_HASH &&
1236 				    map->map_type != BPF_MAP_TYPE_ARRAY) {
1237 					ret = -EOPNOTSUPP;
1238 					goto free_map_tab;
1239 				}
1240 				break;
1241 			case BPF_KPTR_UNREF:
1242 			case BPF_KPTR_REF:
1243 			case BPF_KPTR_PERCPU:
1244 			case BPF_REFCOUNT:
1245 				if (map->map_type != BPF_MAP_TYPE_HASH &&
1246 				    map->map_type != BPF_MAP_TYPE_PERCPU_HASH &&
1247 				    map->map_type != BPF_MAP_TYPE_LRU_HASH &&
1248 				    map->map_type != BPF_MAP_TYPE_LRU_PERCPU_HASH &&
1249 				    map->map_type != BPF_MAP_TYPE_ARRAY &&
1250 				    map->map_type != BPF_MAP_TYPE_PERCPU_ARRAY &&
1251 				    map->map_type != BPF_MAP_TYPE_SK_STORAGE &&
1252 				    map->map_type != BPF_MAP_TYPE_INODE_STORAGE &&
1253 				    map->map_type != BPF_MAP_TYPE_TASK_STORAGE &&
1254 				    map->map_type != BPF_MAP_TYPE_CGRP_STORAGE) {
1255 					ret = -EOPNOTSUPP;
1256 					goto free_map_tab;
1257 				}
1258 				break;
1259 			case BPF_UPTR:
1260 				if (map->map_type != BPF_MAP_TYPE_TASK_STORAGE) {
1261 					ret = -EOPNOTSUPP;
1262 					goto free_map_tab;
1263 				}
1264 				break;
1265 			case BPF_LIST_HEAD:
1266 			case BPF_RB_ROOT:
1267 				if (map->map_type != BPF_MAP_TYPE_HASH &&
1268 				    map->map_type != BPF_MAP_TYPE_LRU_HASH &&
1269 				    map->map_type != BPF_MAP_TYPE_ARRAY) {
1270 					ret = -EOPNOTSUPP;
1271 					goto free_map_tab;
1272 				}
1273 				break;
1274 			default:
1275 				/* Fail if map_type checks are missing for a field type */
1276 				ret = -EOPNOTSUPP;
1277 				goto free_map_tab;
1278 			}
1279 		}
1280 	}
1281 
1282 	ret = btf_check_and_fixup_fields(btf, map->record);
1283 	if (ret < 0)
1284 		goto free_map_tab;
1285 
1286 	if (map->ops->map_check_btf) {
1287 		ret = map->ops->map_check_btf(map, btf, key_type, value_type);
1288 		if (ret < 0)
1289 			goto free_map_tab;
1290 	}
1291 
1292 	return ret;
1293 free_map_tab:
1294 	bpf_map_free_record(map);
1295 	return ret;
1296 }
1297 
1298 static bool bpf_net_capable(void)
1299 {
1300 	return capable(CAP_NET_ADMIN) || capable(CAP_SYS_ADMIN);
1301 }
1302 
1303 #define BPF_MAP_CREATE_LAST_FIELD map_token_fd
1304 /* called via syscall */
1305 static int map_create(union bpf_attr *attr)
1306 {
1307 	const struct bpf_map_ops *ops;
1308 	struct bpf_token *token = NULL;
1309 	int numa_node = bpf_map_attr_numa_node(attr);
1310 	u32 map_type = attr->map_type;
1311 	struct bpf_map *map;
1312 	bool token_flag;
1313 	int f_flags;
1314 	int err;
1315 
1316 	err = CHECK_ATTR(BPF_MAP_CREATE);
1317 	if (err)
1318 		return -EINVAL;
1319 
1320 	/* check BPF_F_TOKEN_FD flag, remember if it's set, and then clear it
1321 	 * to avoid per-map type checks tripping on unknown flag
1322 	 */
1323 	token_flag = attr->map_flags & BPF_F_TOKEN_FD;
1324 	attr->map_flags &= ~BPF_F_TOKEN_FD;
1325 
1326 	if (attr->btf_vmlinux_value_type_id) {
1327 		if (attr->map_type != BPF_MAP_TYPE_STRUCT_OPS ||
1328 		    attr->btf_key_type_id || attr->btf_value_type_id)
1329 			return -EINVAL;
1330 	} else if (attr->btf_key_type_id && !attr->btf_value_type_id) {
1331 		return -EINVAL;
1332 	}
1333 
1334 	if (attr->map_type != BPF_MAP_TYPE_BLOOM_FILTER &&
1335 	    attr->map_type != BPF_MAP_TYPE_ARENA &&
1336 	    attr->map_extra != 0)
1337 		return -EINVAL;
1338 
1339 	f_flags = bpf_get_file_flag(attr->map_flags);
1340 	if (f_flags < 0)
1341 		return f_flags;
1342 
1343 	if (numa_node != NUMA_NO_NODE &&
1344 	    ((unsigned int)numa_node >= nr_node_ids ||
1345 	     !node_online(numa_node)))
1346 		return -EINVAL;
1347 
1348 	/* find map type and init map: hashtable vs rbtree vs bloom vs ... */
1349 	map_type = attr->map_type;
1350 	if (map_type >= ARRAY_SIZE(bpf_map_types))
1351 		return -EINVAL;
1352 	map_type = array_index_nospec(map_type, ARRAY_SIZE(bpf_map_types));
1353 	ops = bpf_map_types[map_type];
1354 	if (!ops)
1355 		return -EINVAL;
1356 
1357 	if (ops->map_alloc_check) {
1358 		err = ops->map_alloc_check(attr);
1359 		if (err)
1360 			return err;
1361 	}
1362 	if (attr->map_ifindex)
1363 		ops = &bpf_map_offload_ops;
1364 	if (!ops->map_mem_usage)
1365 		return -EINVAL;
1366 
1367 	if (token_flag) {
1368 		token = bpf_token_get_from_fd(attr->map_token_fd);
1369 		if (IS_ERR(token))
1370 			return PTR_ERR(token);
1371 
1372 		/* if current token doesn't grant map creation permissions,
1373 		 * then we can't use this token, so ignore it and rely on
1374 		 * system-wide capabilities checks
1375 		 */
1376 		if (!bpf_token_allow_cmd(token, BPF_MAP_CREATE) ||
1377 		    !bpf_token_allow_map_type(token, attr->map_type)) {
1378 			bpf_token_put(token);
1379 			token = NULL;
1380 		}
1381 	}
1382 
1383 	err = -EPERM;
1384 
1385 	/* Intent here is for unprivileged_bpf_disabled to block BPF map
1386 	 * creation for unprivileged users; other actions depend
1387 	 * on fd availability and access to bpffs, so are dependent on
1388 	 * object creation success. Even with unprivileged BPF disabled,
1389 	 * capability checks are still carried out.
1390 	 */
1391 	if (sysctl_unprivileged_bpf_disabled && !bpf_token_capable(token, CAP_BPF))
1392 		goto put_token;
1393 
1394 	/* check privileged map type permissions */
1395 	switch (map_type) {
1396 	case BPF_MAP_TYPE_ARRAY:
1397 	case BPF_MAP_TYPE_PERCPU_ARRAY:
1398 	case BPF_MAP_TYPE_PROG_ARRAY:
1399 	case BPF_MAP_TYPE_PERF_EVENT_ARRAY:
1400 	case BPF_MAP_TYPE_CGROUP_ARRAY:
1401 	case BPF_MAP_TYPE_ARRAY_OF_MAPS:
1402 	case BPF_MAP_TYPE_HASH:
1403 	case BPF_MAP_TYPE_PERCPU_HASH:
1404 	case BPF_MAP_TYPE_HASH_OF_MAPS:
1405 	case BPF_MAP_TYPE_RINGBUF:
1406 	case BPF_MAP_TYPE_USER_RINGBUF:
1407 	case BPF_MAP_TYPE_CGROUP_STORAGE:
1408 	case BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE:
1409 		/* unprivileged */
1410 		break;
1411 	case BPF_MAP_TYPE_SK_STORAGE:
1412 	case BPF_MAP_TYPE_INODE_STORAGE:
1413 	case BPF_MAP_TYPE_TASK_STORAGE:
1414 	case BPF_MAP_TYPE_CGRP_STORAGE:
1415 	case BPF_MAP_TYPE_BLOOM_FILTER:
1416 	case BPF_MAP_TYPE_LPM_TRIE:
1417 	case BPF_MAP_TYPE_REUSEPORT_SOCKARRAY:
1418 	case BPF_MAP_TYPE_STACK_TRACE:
1419 	case BPF_MAP_TYPE_QUEUE:
1420 	case BPF_MAP_TYPE_STACK:
1421 	case BPF_MAP_TYPE_LRU_HASH:
1422 	case BPF_MAP_TYPE_LRU_PERCPU_HASH:
1423 	case BPF_MAP_TYPE_STRUCT_OPS:
1424 	case BPF_MAP_TYPE_CPUMAP:
1425 	case BPF_MAP_TYPE_ARENA:
1426 		if (!bpf_token_capable(token, CAP_BPF))
1427 			goto put_token;
1428 		break;
1429 	case BPF_MAP_TYPE_SOCKMAP:
1430 	case BPF_MAP_TYPE_SOCKHASH:
1431 	case BPF_MAP_TYPE_DEVMAP:
1432 	case BPF_MAP_TYPE_DEVMAP_HASH:
1433 	case BPF_MAP_TYPE_XSKMAP:
1434 		if (!bpf_token_capable(token, CAP_NET_ADMIN))
1435 			goto put_token;
1436 		break;
1437 	default:
1438 		WARN(1, "unsupported map type %d", map_type);
1439 		goto put_token;
1440 	}
1441 
1442 	map = ops->map_alloc(attr);
1443 	if (IS_ERR(map)) {
1444 		err = PTR_ERR(map);
1445 		goto put_token;
1446 	}
1447 	map->ops = ops;
1448 	map->map_type = map_type;
1449 
1450 	err = bpf_obj_name_cpy(map->name, attr->map_name,
1451 			       sizeof(attr->map_name));
1452 	if (err < 0)
1453 		goto free_map;
1454 
1455 	atomic64_set(&map->refcnt, 1);
1456 	atomic64_set(&map->usercnt, 1);
1457 	mutex_init(&map->freeze_mutex);
1458 	spin_lock_init(&map->owner.lock);
1459 
1460 	if (attr->btf_key_type_id || attr->btf_value_type_id ||
1461 	    /* Even the map's value is a kernel's struct,
1462 	     * the bpf_prog.o must have BTF to begin with
1463 	     * to figure out the corresponding kernel's
1464 	     * counter part.  Thus, attr->btf_fd has
1465 	     * to be valid also.
1466 	     */
1467 	    attr->btf_vmlinux_value_type_id) {
1468 		struct btf *btf;
1469 
1470 		btf = btf_get_by_fd(attr->btf_fd);
1471 		if (IS_ERR(btf)) {
1472 			err = PTR_ERR(btf);
1473 			goto free_map;
1474 		}
1475 		if (btf_is_kernel(btf)) {
1476 			btf_put(btf);
1477 			err = -EACCES;
1478 			goto free_map;
1479 		}
1480 		map->btf = btf;
1481 
1482 		if (attr->btf_value_type_id) {
1483 			err = map_check_btf(map, token, btf, attr->btf_key_type_id,
1484 					    attr->btf_value_type_id);
1485 			if (err)
1486 				goto free_map;
1487 		}
1488 
1489 		map->btf_key_type_id = attr->btf_key_type_id;
1490 		map->btf_value_type_id = attr->btf_value_type_id;
1491 		map->btf_vmlinux_value_type_id =
1492 			attr->btf_vmlinux_value_type_id;
1493 	}
1494 
1495 	err = security_bpf_map_create(map, attr, token);
1496 	if (err)
1497 		goto free_map_sec;
1498 
1499 	err = bpf_map_alloc_id(map);
1500 	if (err)
1501 		goto free_map_sec;
1502 
1503 	bpf_map_save_memcg(map);
1504 	bpf_token_put(token);
1505 
1506 	err = bpf_map_new_fd(map, f_flags);
1507 	if (err < 0) {
1508 		/* failed to allocate fd.
1509 		 * bpf_map_put_with_uref() is needed because the above
1510 		 * bpf_map_alloc_id() has published the map
1511 		 * to the userspace and the userspace may
1512 		 * have refcnt-ed it through BPF_MAP_GET_FD_BY_ID.
1513 		 */
1514 		bpf_map_put_with_uref(map);
1515 		return err;
1516 	}
1517 
1518 	return err;
1519 
1520 free_map_sec:
1521 	security_bpf_map_free(map);
1522 free_map:
1523 	bpf_map_free(map);
1524 put_token:
1525 	bpf_token_put(token);
1526 	return err;
1527 }
1528 
1529 void bpf_map_inc(struct bpf_map *map)
1530 {
1531 	atomic64_inc(&map->refcnt);
1532 }
1533 EXPORT_SYMBOL_GPL(bpf_map_inc);
1534 
1535 void bpf_map_inc_with_uref(struct bpf_map *map)
1536 {
1537 	atomic64_inc(&map->refcnt);
1538 	atomic64_inc(&map->usercnt);
1539 }
1540 EXPORT_SYMBOL_GPL(bpf_map_inc_with_uref);
1541 
1542 struct bpf_map *bpf_map_get(u32 ufd)
1543 {
1544 	CLASS(fd, f)(ufd);
1545 	struct bpf_map *map = __bpf_map_get(f);
1546 
1547 	if (!IS_ERR(map))
1548 		bpf_map_inc(map);
1549 
1550 	return map;
1551 }
1552 EXPORT_SYMBOL(bpf_map_get);
1553 
1554 struct bpf_map *bpf_map_get_with_uref(u32 ufd)
1555 {
1556 	CLASS(fd, f)(ufd);
1557 	struct bpf_map *map = __bpf_map_get(f);
1558 
1559 	if (!IS_ERR(map))
1560 		bpf_map_inc_with_uref(map);
1561 
1562 	return map;
1563 }
1564 
1565 /* map_idr_lock should have been held or the map should have been
1566  * protected by rcu read lock.
1567  */
1568 struct bpf_map *__bpf_map_inc_not_zero(struct bpf_map *map, bool uref)
1569 {
1570 	int refold;
1571 
1572 	refold = atomic64_fetch_add_unless(&map->refcnt, 1, 0);
1573 	if (!refold)
1574 		return ERR_PTR(-ENOENT);
1575 	if (uref)
1576 		atomic64_inc(&map->usercnt);
1577 
1578 	return map;
1579 }
1580 
1581 struct bpf_map *bpf_map_inc_not_zero(struct bpf_map *map)
1582 {
1583 	spin_lock_bh(&map_idr_lock);
1584 	map = __bpf_map_inc_not_zero(map, false);
1585 	spin_unlock_bh(&map_idr_lock);
1586 
1587 	return map;
1588 }
1589 EXPORT_SYMBOL_GPL(bpf_map_inc_not_zero);
1590 
1591 int __weak bpf_stackmap_copy(struct bpf_map *map, void *key, void *value)
1592 {
1593 	return -ENOTSUPP;
1594 }
1595 
1596 static void *__bpf_copy_key(void __user *ukey, u64 key_size)
1597 {
1598 	if (key_size)
1599 		return vmemdup_user(ukey, key_size);
1600 
1601 	if (ukey)
1602 		return ERR_PTR(-EINVAL);
1603 
1604 	return NULL;
1605 }
1606 
1607 static void *___bpf_copy_key(bpfptr_t ukey, u64 key_size)
1608 {
1609 	if (key_size)
1610 		return kvmemdup_bpfptr(ukey, key_size);
1611 
1612 	if (!bpfptr_is_null(ukey))
1613 		return ERR_PTR(-EINVAL);
1614 
1615 	return NULL;
1616 }
1617 
1618 /* last field in 'union bpf_attr' used by this command */
1619 #define BPF_MAP_LOOKUP_ELEM_LAST_FIELD flags
1620 
1621 static int map_lookup_elem(union bpf_attr *attr)
1622 {
1623 	void __user *ukey = u64_to_user_ptr(attr->key);
1624 	void __user *uvalue = u64_to_user_ptr(attr->value);
1625 	struct bpf_map *map;
1626 	void *key, *value;
1627 	u32 value_size;
1628 	int err;
1629 
1630 	if (CHECK_ATTR(BPF_MAP_LOOKUP_ELEM))
1631 		return -EINVAL;
1632 
1633 	if (attr->flags & ~BPF_F_LOCK)
1634 		return -EINVAL;
1635 
1636 	CLASS(fd, f)(attr->map_fd);
1637 	map = __bpf_map_get(f);
1638 	if (IS_ERR(map))
1639 		return PTR_ERR(map);
1640 	if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ))
1641 		return -EPERM;
1642 
1643 	if ((attr->flags & BPF_F_LOCK) &&
1644 	    !btf_record_has_field(map->record, BPF_SPIN_LOCK))
1645 		return -EINVAL;
1646 
1647 	key = __bpf_copy_key(ukey, map->key_size);
1648 	if (IS_ERR(key))
1649 		return PTR_ERR(key);
1650 
1651 	value_size = bpf_map_value_size(map);
1652 
1653 	err = -ENOMEM;
1654 	value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN);
1655 	if (!value)
1656 		goto free_key;
1657 
1658 	if (map->map_type == BPF_MAP_TYPE_BLOOM_FILTER) {
1659 		if (copy_from_user(value, uvalue, value_size))
1660 			err = -EFAULT;
1661 		else
1662 			err = bpf_map_copy_value(map, key, value, attr->flags);
1663 		goto free_value;
1664 	}
1665 
1666 	err = bpf_map_copy_value(map, key, value, attr->flags);
1667 	if (err)
1668 		goto free_value;
1669 
1670 	err = -EFAULT;
1671 	if (copy_to_user(uvalue, value, value_size) != 0)
1672 		goto free_value;
1673 
1674 	err = 0;
1675 
1676 free_value:
1677 	kvfree(value);
1678 free_key:
1679 	kvfree(key);
1680 	return err;
1681 }
1682 
1683 
1684 #define BPF_MAP_UPDATE_ELEM_LAST_FIELD flags
1685 
1686 static int map_update_elem(union bpf_attr *attr, bpfptr_t uattr)
1687 {
1688 	bpfptr_t ukey = make_bpfptr(attr->key, uattr.is_kernel);
1689 	bpfptr_t uvalue = make_bpfptr(attr->value, uattr.is_kernel);
1690 	struct bpf_map *map;
1691 	void *key, *value;
1692 	u32 value_size;
1693 	int err;
1694 
1695 	if (CHECK_ATTR(BPF_MAP_UPDATE_ELEM))
1696 		return -EINVAL;
1697 
1698 	CLASS(fd, f)(attr->map_fd);
1699 	map = __bpf_map_get(f);
1700 	if (IS_ERR(map))
1701 		return PTR_ERR(map);
1702 	bpf_map_write_active_inc(map);
1703 	if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
1704 		err = -EPERM;
1705 		goto err_put;
1706 	}
1707 
1708 	if ((attr->flags & BPF_F_LOCK) &&
1709 	    !btf_record_has_field(map->record, BPF_SPIN_LOCK)) {
1710 		err = -EINVAL;
1711 		goto err_put;
1712 	}
1713 
1714 	key = ___bpf_copy_key(ukey, map->key_size);
1715 	if (IS_ERR(key)) {
1716 		err = PTR_ERR(key);
1717 		goto err_put;
1718 	}
1719 
1720 	value_size = bpf_map_value_size(map);
1721 	value = kvmemdup_bpfptr(uvalue, value_size);
1722 	if (IS_ERR(value)) {
1723 		err = PTR_ERR(value);
1724 		goto free_key;
1725 	}
1726 
1727 	err = bpf_map_update_value(map, fd_file(f), key, value, attr->flags);
1728 	if (!err)
1729 		maybe_wait_bpf_programs(map);
1730 
1731 	kvfree(value);
1732 free_key:
1733 	kvfree(key);
1734 err_put:
1735 	bpf_map_write_active_dec(map);
1736 	return err;
1737 }
1738 
1739 #define BPF_MAP_DELETE_ELEM_LAST_FIELD key
1740 
1741 static int map_delete_elem(union bpf_attr *attr, bpfptr_t uattr)
1742 {
1743 	bpfptr_t ukey = make_bpfptr(attr->key, uattr.is_kernel);
1744 	struct bpf_map *map;
1745 	void *key;
1746 	int err;
1747 
1748 	if (CHECK_ATTR(BPF_MAP_DELETE_ELEM))
1749 		return -EINVAL;
1750 
1751 	CLASS(fd, f)(attr->map_fd);
1752 	map = __bpf_map_get(f);
1753 	if (IS_ERR(map))
1754 		return PTR_ERR(map);
1755 	bpf_map_write_active_inc(map);
1756 	if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
1757 		err = -EPERM;
1758 		goto err_put;
1759 	}
1760 
1761 	key = ___bpf_copy_key(ukey, map->key_size);
1762 	if (IS_ERR(key)) {
1763 		err = PTR_ERR(key);
1764 		goto err_put;
1765 	}
1766 
1767 	if (bpf_map_is_offloaded(map)) {
1768 		err = bpf_map_offload_delete_elem(map, key);
1769 		goto out;
1770 	} else if (IS_FD_PROG_ARRAY(map) ||
1771 		   map->map_type == BPF_MAP_TYPE_STRUCT_OPS) {
1772 		/* These maps require sleepable context */
1773 		err = map->ops->map_delete_elem(map, key);
1774 		goto out;
1775 	}
1776 
1777 	bpf_disable_instrumentation();
1778 	rcu_read_lock();
1779 	err = map->ops->map_delete_elem(map, key);
1780 	rcu_read_unlock();
1781 	bpf_enable_instrumentation();
1782 	if (!err)
1783 		maybe_wait_bpf_programs(map);
1784 out:
1785 	kvfree(key);
1786 err_put:
1787 	bpf_map_write_active_dec(map);
1788 	return err;
1789 }
1790 
1791 /* last field in 'union bpf_attr' used by this command */
1792 #define BPF_MAP_GET_NEXT_KEY_LAST_FIELD next_key
1793 
1794 static int map_get_next_key(union bpf_attr *attr)
1795 {
1796 	void __user *ukey = u64_to_user_ptr(attr->key);
1797 	void __user *unext_key = u64_to_user_ptr(attr->next_key);
1798 	struct bpf_map *map;
1799 	void *key, *next_key;
1800 	int err;
1801 
1802 	if (CHECK_ATTR(BPF_MAP_GET_NEXT_KEY))
1803 		return -EINVAL;
1804 
1805 	CLASS(fd, f)(attr->map_fd);
1806 	map = __bpf_map_get(f);
1807 	if (IS_ERR(map))
1808 		return PTR_ERR(map);
1809 	if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ))
1810 		return -EPERM;
1811 
1812 	if (ukey) {
1813 		key = __bpf_copy_key(ukey, map->key_size);
1814 		if (IS_ERR(key))
1815 			return PTR_ERR(key);
1816 	} else {
1817 		key = NULL;
1818 	}
1819 
1820 	err = -ENOMEM;
1821 	next_key = kvmalloc(map->key_size, GFP_USER);
1822 	if (!next_key)
1823 		goto free_key;
1824 
1825 	if (bpf_map_is_offloaded(map)) {
1826 		err = bpf_map_offload_get_next_key(map, key, next_key);
1827 		goto out;
1828 	}
1829 
1830 	rcu_read_lock();
1831 	err = map->ops->map_get_next_key(map, key, next_key);
1832 	rcu_read_unlock();
1833 out:
1834 	if (err)
1835 		goto free_next_key;
1836 
1837 	err = -EFAULT;
1838 	if (copy_to_user(unext_key, next_key, map->key_size) != 0)
1839 		goto free_next_key;
1840 
1841 	err = 0;
1842 
1843 free_next_key:
1844 	kvfree(next_key);
1845 free_key:
1846 	kvfree(key);
1847 	return err;
1848 }
1849 
1850 int generic_map_delete_batch(struct bpf_map *map,
1851 			     const union bpf_attr *attr,
1852 			     union bpf_attr __user *uattr)
1853 {
1854 	void __user *keys = u64_to_user_ptr(attr->batch.keys);
1855 	u32 cp, max_count;
1856 	int err = 0;
1857 	void *key;
1858 
1859 	if (attr->batch.elem_flags & ~BPF_F_LOCK)
1860 		return -EINVAL;
1861 
1862 	if ((attr->batch.elem_flags & BPF_F_LOCK) &&
1863 	    !btf_record_has_field(map->record, BPF_SPIN_LOCK)) {
1864 		return -EINVAL;
1865 	}
1866 
1867 	max_count = attr->batch.count;
1868 	if (!max_count)
1869 		return 0;
1870 
1871 	if (put_user(0, &uattr->batch.count))
1872 		return -EFAULT;
1873 
1874 	key = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN);
1875 	if (!key)
1876 		return -ENOMEM;
1877 
1878 	for (cp = 0; cp < max_count; cp++) {
1879 		err = -EFAULT;
1880 		if (copy_from_user(key, keys + cp * map->key_size,
1881 				   map->key_size))
1882 			break;
1883 
1884 		if (bpf_map_is_offloaded(map)) {
1885 			err = bpf_map_offload_delete_elem(map, key);
1886 			break;
1887 		}
1888 
1889 		bpf_disable_instrumentation();
1890 		rcu_read_lock();
1891 		err = map->ops->map_delete_elem(map, key);
1892 		rcu_read_unlock();
1893 		bpf_enable_instrumentation();
1894 		if (err)
1895 			break;
1896 		cond_resched();
1897 	}
1898 	if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp)))
1899 		err = -EFAULT;
1900 
1901 	kvfree(key);
1902 
1903 	return err;
1904 }
1905 
1906 int generic_map_update_batch(struct bpf_map *map, struct file *map_file,
1907 			     const union bpf_attr *attr,
1908 			     union bpf_attr __user *uattr)
1909 {
1910 	void __user *values = u64_to_user_ptr(attr->batch.values);
1911 	void __user *keys = u64_to_user_ptr(attr->batch.keys);
1912 	u32 value_size, cp, max_count;
1913 	void *key, *value;
1914 	int err = 0;
1915 
1916 	if (attr->batch.elem_flags & ~BPF_F_LOCK)
1917 		return -EINVAL;
1918 
1919 	if ((attr->batch.elem_flags & BPF_F_LOCK) &&
1920 	    !btf_record_has_field(map->record, BPF_SPIN_LOCK)) {
1921 		return -EINVAL;
1922 	}
1923 
1924 	value_size = bpf_map_value_size(map);
1925 
1926 	max_count = attr->batch.count;
1927 	if (!max_count)
1928 		return 0;
1929 
1930 	if (put_user(0, &uattr->batch.count))
1931 		return -EFAULT;
1932 
1933 	key = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN);
1934 	if (!key)
1935 		return -ENOMEM;
1936 
1937 	value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN);
1938 	if (!value) {
1939 		kvfree(key);
1940 		return -ENOMEM;
1941 	}
1942 
1943 	for (cp = 0; cp < max_count; cp++) {
1944 		err = -EFAULT;
1945 		if (copy_from_user(key, keys + cp * map->key_size,
1946 		    map->key_size) ||
1947 		    copy_from_user(value, values + cp * value_size, value_size))
1948 			break;
1949 
1950 		err = bpf_map_update_value(map, map_file, key, value,
1951 					   attr->batch.elem_flags);
1952 
1953 		if (err)
1954 			break;
1955 		cond_resched();
1956 	}
1957 
1958 	if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp)))
1959 		err = -EFAULT;
1960 
1961 	kvfree(value);
1962 	kvfree(key);
1963 
1964 	return err;
1965 }
1966 
1967 #define MAP_LOOKUP_RETRIES 3
1968 
1969 int generic_map_lookup_batch(struct bpf_map *map,
1970 				    const union bpf_attr *attr,
1971 				    union bpf_attr __user *uattr)
1972 {
1973 	void __user *uobatch = u64_to_user_ptr(attr->batch.out_batch);
1974 	void __user *ubatch = u64_to_user_ptr(attr->batch.in_batch);
1975 	void __user *values = u64_to_user_ptr(attr->batch.values);
1976 	void __user *keys = u64_to_user_ptr(attr->batch.keys);
1977 	void *buf, *buf_prevkey, *prev_key, *key, *value;
1978 	int err, retry = MAP_LOOKUP_RETRIES;
1979 	u32 value_size, cp, max_count;
1980 
1981 	if (attr->batch.elem_flags & ~BPF_F_LOCK)
1982 		return -EINVAL;
1983 
1984 	if ((attr->batch.elem_flags & BPF_F_LOCK) &&
1985 	    !btf_record_has_field(map->record, BPF_SPIN_LOCK))
1986 		return -EINVAL;
1987 
1988 	value_size = bpf_map_value_size(map);
1989 
1990 	max_count = attr->batch.count;
1991 	if (!max_count)
1992 		return 0;
1993 
1994 	if (put_user(0, &uattr->batch.count))
1995 		return -EFAULT;
1996 
1997 	buf_prevkey = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN);
1998 	if (!buf_prevkey)
1999 		return -ENOMEM;
2000 
2001 	buf = kvmalloc(map->key_size + value_size, GFP_USER | __GFP_NOWARN);
2002 	if (!buf) {
2003 		kvfree(buf_prevkey);
2004 		return -ENOMEM;
2005 	}
2006 
2007 	err = -EFAULT;
2008 	prev_key = NULL;
2009 	if (ubatch && copy_from_user(buf_prevkey, ubatch, map->key_size))
2010 		goto free_buf;
2011 	key = buf;
2012 	value = key + map->key_size;
2013 	if (ubatch)
2014 		prev_key = buf_prevkey;
2015 
2016 	for (cp = 0; cp < max_count;) {
2017 		rcu_read_lock();
2018 		err = map->ops->map_get_next_key(map, prev_key, key);
2019 		rcu_read_unlock();
2020 		if (err)
2021 			break;
2022 		err = bpf_map_copy_value(map, key, value,
2023 					 attr->batch.elem_flags);
2024 
2025 		if (err == -ENOENT) {
2026 			if (retry) {
2027 				retry--;
2028 				continue;
2029 			}
2030 			err = -EINTR;
2031 			break;
2032 		}
2033 
2034 		if (err)
2035 			goto free_buf;
2036 
2037 		if (copy_to_user(keys + cp * map->key_size, key,
2038 				 map->key_size)) {
2039 			err = -EFAULT;
2040 			goto free_buf;
2041 		}
2042 		if (copy_to_user(values + cp * value_size, value, value_size)) {
2043 			err = -EFAULT;
2044 			goto free_buf;
2045 		}
2046 
2047 		if (!prev_key)
2048 			prev_key = buf_prevkey;
2049 
2050 		swap(prev_key, key);
2051 		retry = MAP_LOOKUP_RETRIES;
2052 		cp++;
2053 		cond_resched();
2054 	}
2055 
2056 	if (err == -EFAULT)
2057 		goto free_buf;
2058 
2059 	if ((copy_to_user(&uattr->batch.count, &cp, sizeof(cp)) ||
2060 		    (cp && copy_to_user(uobatch, prev_key, map->key_size))))
2061 		err = -EFAULT;
2062 
2063 free_buf:
2064 	kvfree(buf_prevkey);
2065 	kvfree(buf);
2066 	return err;
2067 }
2068 
2069 #define BPF_MAP_LOOKUP_AND_DELETE_ELEM_LAST_FIELD flags
2070 
2071 static int map_lookup_and_delete_elem(union bpf_attr *attr)
2072 {
2073 	void __user *ukey = u64_to_user_ptr(attr->key);
2074 	void __user *uvalue = u64_to_user_ptr(attr->value);
2075 	struct bpf_map *map;
2076 	void *key, *value;
2077 	u32 value_size;
2078 	int err;
2079 
2080 	if (CHECK_ATTR(BPF_MAP_LOOKUP_AND_DELETE_ELEM))
2081 		return -EINVAL;
2082 
2083 	if (attr->flags & ~BPF_F_LOCK)
2084 		return -EINVAL;
2085 
2086 	CLASS(fd, f)(attr->map_fd);
2087 	map = __bpf_map_get(f);
2088 	if (IS_ERR(map))
2089 		return PTR_ERR(map);
2090 	bpf_map_write_active_inc(map);
2091 	if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ) ||
2092 	    !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
2093 		err = -EPERM;
2094 		goto err_put;
2095 	}
2096 
2097 	if (attr->flags &&
2098 	    (map->map_type == BPF_MAP_TYPE_QUEUE ||
2099 	     map->map_type == BPF_MAP_TYPE_STACK)) {
2100 		err = -EINVAL;
2101 		goto err_put;
2102 	}
2103 
2104 	if ((attr->flags & BPF_F_LOCK) &&
2105 	    !btf_record_has_field(map->record, BPF_SPIN_LOCK)) {
2106 		err = -EINVAL;
2107 		goto err_put;
2108 	}
2109 
2110 	key = __bpf_copy_key(ukey, map->key_size);
2111 	if (IS_ERR(key)) {
2112 		err = PTR_ERR(key);
2113 		goto err_put;
2114 	}
2115 
2116 	value_size = bpf_map_value_size(map);
2117 
2118 	err = -ENOMEM;
2119 	value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN);
2120 	if (!value)
2121 		goto free_key;
2122 
2123 	err = -ENOTSUPP;
2124 	if (map->map_type == BPF_MAP_TYPE_QUEUE ||
2125 	    map->map_type == BPF_MAP_TYPE_STACK) {
2126 		err = map->ops->map_pop_elem(map, value);
2127 	} else if (map->map_type == BPF_MAP_TYPE_HASH ||
2128 		   map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
2129 		   map->map_type == BPF_MAP_TYPE_LRU_HASH ||
2130 		   map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
2131 		if (!bpf_map_is_offloaded(map)) {
2132 			bpf_disable_instrumentation();
2133 			rcu_read_lock();
2134 			err = map->ops->map_lookup_and_delete_elem(map, key, value, attr->flags);
2135 			rcu_read_unlock();
2136 			bpf_enable_instrumentation();
2137 		}
2138 	}
2139 
2140 	if (err)
2141 		goto free_value;
2142 
2143 	if (copy_to_user(uvalue, value, value_size) != 0) {
2144 		err = -EFAULT;
2145 		goto free_value;
2146 	}
2147 
2148 	err = 0;
2149 
2150 free_value:
2151 	kvfree(value);
2152 free_key:
2153 	kvfree(key);
2154 err_put:
2155 	bpf_map_write_active_dec(map);
2156 	return err;
2157 }
2158 
2159 #define BPF_MAP_FREEZE_LAST_FIELD map_fd
2160 
2161 static int map_freeze(const union bpf_attr *attr)
2162 {
2163 	int err = 0;
2164 	struct bpf_map *map;
2165 
2166 	if (CHECK_ATTR(BPF_MAP_FREEZE))
2167 		return -EINVAL;
2168 
2169 	CLASS(fd, f)(attr->map_fd);
2170 	map = __bpf_map_get(f);
2171 	if (IS_ERR(map))
2172 		return PTR_ERR(map);
2173 
2174 	if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS || !IS_ERR_OR_NULL(map->record))
2175 		return -ENOTSUPP;
2176 
2177 	if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE))
2178 		return -EPERM;
2179 
2180 	mutex_lock(&map->freeze_mutex);
2181 	if (bpf_map_write_active(map)) {
2182 		err = -EBUSY;
2183 		goto err_put;
2184 	}
2185 	if (READ_ONCE(map->frozen)) {
2186 		err = -EBUSY;
2187 		goto err_put;
2188 	}
2189 
2190 	WRITE_ONCE(map->frozen, true);
2191 err_put:
2192 	mutex_unlock(&map->freeze_mutex);
2193 	return err;
2194 }
2195 
2196 static const struct bpf_prog_ops * const bpf_prog_types[] = {
2197 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) \
2198 	[_id] = & _name ## _prog_ops,
2199 #define BPF_MAP_TYPE(_id, _ops)
2200 #define BPF_LINK_TYPE(_id, _name)
2201 #include <linux/bpf_types.h>
2202 #undef BPF_PROG_TYPE
2203 #undef BPF_MAP_TYPE
2204 #undef BPF_LINK_TYPE
2205 };
2206 
2207 static int find_prog_type(enum bpf_prog_type type, struct bpf_prog *prog)
2208 {
2209 	const struct bpf_prog_ops *ops;
2210 
2211 	if (type >= ARRAY_SIZE(bpf_prog_types))
2212 		return -EINVAL;
2213 	type = array_index_nospec(type, ARRAY_SIZE(bpf_prog_types));
2214 	ops = bpf_prog_types[type];
2215 	if (!ops)
2216 		return -EINVAL;
2217 
2218 	if (!bpf_prog_is_offloaded(prog->aux))
2219 		prog->aux->ops = ops;
2220 	else
2221 		prog->aux->ops = &bpf_offload_prog_ops;
2222 	prog->type = type;
2223 	return 0;
2224 }
2225 
2226 enum bpf_audit {
2227 	BPF_AUDIT_LOAD,
2228 	BPF_AUDIT_UNLOAD,
2229 	BPF_AUDIT_MAX,
2230 };
2231 
2232 static const char * const bpf_audit_str[BPF_AUDIT_MAX] = {
2233 	[BPF_AUDIT_LOAD]   = "LOAD",
2234 	[BPF_AUDIT_UNLOAD] = "UNLOAD",
2235 };
2236 
2237 static void bpf_audit_prog(const struct bpf_prog *prog, unsigned int op)
2238 {
2239 	struct audit_context *ctx = NULL;
2240 	struct audit_buffer *ab;
2241 
2242 	if (WARN_ON_ONCE(op >= BPF_AUDIT_MAX))
2243 		return;
2244 	if (audit_enabled == AUDIT_OFF)
2245 		return;
2246 	if (!in_irq() && !irqs_disabled())
2247 		ctx = audit_context();
2248 	ab = audit_log_start(ctx, GFP_ATOMIC, AUDIT_BPF);
2249 	if (unlikely(!ab))
2250 		return;
2251 	audit_log_format(ab, "prog-id=%u op=%s",
2252 			 prog->aux->id, bpf_audit_str[op]);
2253 	audit_log_end(ab);
2254 }
2255 
2256 static int bpf_prog_alloc_id(struct bpf_prog *prog)
2257 {
2258 	int id;
2259 
2260 	idr_preload(GFP_KERNEL);
2261 	spin_lock_bh(&prog_idr_lock);
2262 	id = idr_alloc_cyclic(&prog_idr, prog, 1, INT_MAX, GFP_ATOMIC);
2263 	if (id > 0)
2264 		prog->aux->id = id;
2265 	spin_unlock_bh(&prog_idr_lock);
2266 	idr_preload_end();
2267 
2268 	/* id is in [1, INT_MAX) */
2269 	if (WARN_ON_ONCE(!id))
2270 		return -ENOSPC;
2271 
2272 	return id > 0 ? 0 : id;
2273 }
2274 
2275 void bpf_prog_free_id(struct bpf_prog *prog)
2276 {
2277 	unsigned long flags;
2278 
2279 	/* cBPF to eBPF migrations are currently not in the idr store.
2280 	 * Offloaded programs are removed from the store when their device
2281 	 * disappears - even if someone grabs an fd to them they are unusable,
2282 	 * simply waiting for refcnt to drop to be freed.
2283 	 */
2284 	if (!prog->aux->id)
2285 		return;
2286 
2287 	spin_lock_irqsave(&prog_idr_lock, flags);
2288 	idr_remove(&prog_idr, prog->aux->id);
2289 	prog->aux->id = 0;
2290 	spin_unlock_irqrestore(&prog_idr_lock, flags);
2291 }
2292 
2293 static void __bpf_prog_put_rcu(struct rcu_head *rcu)
2294 {
2295 	struct bpf_prog_aux *aux = container_of(rcu, struct bpf_prog_aux, rcu);
2296 
2297 	kvfree(aux->func_info);
2298 	kfree(aux->func_info_aux);
2299 	free_uid(aux->user);
2300 	security_bpf_prog_free(aux->prog);
2301 	bpf_prog_free(aux->prog);
2302 }
2303 
2304 static void __bpf_prog_put_noref(struct bpf_prog *prog, bool deferred)
2305 {
2306 	bpf_prog_kallsyms_del_all(prog);
2307 	btf_put(prog->aux->btf);
2308 	module_put(prog->aux->mod);
2309 	kvfree(prog->aux->jited_linfo);
2310 	kvfree(prog->aux->linfo);
2311 	kfree(prog->aux->kfunc_tab);
2312 	if (prog->aux->attach_btf)
2313 		btf_put(prog->aux->attach_btf);
2314 
2315 	if (deferred) {
2316 		if (prog->sleepable)
2317 			call_rcu_tasks_trace(&prog->aux->rcu, __bpf_prog_put_rcu);
2318 		else
2319 			call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu);
2320 	} else {
2321 		__bpf_prog_put_rcu(&prog->aux->rcu);
2322 	}
2323 }
2324 
2325 static void bpf_prog_put_deferred(struct work_struct *work)
2326 {
2327 	struct bpf_prog_aux *aux;
2328 	struct bpf_prog *prog;
2329 
2330 	aux = container_of(work, struct bpf_prog_aux, work);
2331 	prog = aux->prog;
2332 	perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_UNLOAD, 0);
2333 	bpf_audit_prog(prog, BPF_AUDIT_UNLOAD);
2334 	bpf_prog_free_id(prog);
2335 	__bpf_prog_put_noref(prog, true);
2336 }
2337 
2338 static void __bpf_prog_put(struct bpf_prog *prog)
2339 {
2340 	struct bpf_prog_aux *aux = prog->aux;
2341 
2342 	if (atomic64_dec_and_test(&aux->refcnt)) {
2343 		if (in_irq() || irqs_disabled()) {
2344 			INIT_WORK(&aux->work, bpf_prog_put_deferred);
2345 			schedule_work(&aux->work);
2346 		} else {
2347 			bpf_prog_put_deferred(&aux->work);
2348 		}
2349 	}
2350 }
2351 
2352 void bpf_prog_put(struct bpf_prog *prog)
2353 {
2354 	__bpf_prog_put(prog);
2355 }
2356 EXPORT_SYMBOL_GPL(bpf_prog_put);
2357 
2358 static int bpf_prog_release(struct inode *inode, struct file *filp)
2359 {
2360 	struct bpf_prog *prog = filp->private_data;
2361 
2362 	bpf_prog_put(prog);
2363 	return 0;
2364 }
2365 
2366 struct bpf_prog_kstats {
2367 	u64 nsecs;
2368 	u64 cnt;
2369 	u64 misses;
2370 };
2371 
2372 void notrace bpf_prog_inc_misses_counter(struct bpf_prog *prog)
2373 {
2374 	struct bpf_prog_stats *stats;
2375 	unsigned int flags;
2376 
2377 	stats = this_cpu_ptr(prog->stats);
2378 	flags = u64_stats_update_begin_irqsave(&stats->syncp);
2379 	u64_stats_inc(&stats->misses);
2380 	u64_stats_update_end_irqrestore(&stats->syncp, flags);
2381 }
2382 
2383 static void bpf_prog_get_stats(const struct bpf_prog *prog,
2384 			       struct bpf_prog_kstats *stats)
2385 {
2386 	u64 nsecs = 0, cnt = 0, misses = 0;
2387 	int cpu;
2388 
2389 	for_each_possible_cpu(cpu) {
2390 		const struct bpf_prog_stats *st;
2391 		unsigned int start;
2392 		u64 tnsecs, tcnt, tmisses;
2393 
2394 		st = per_cpu_ptr(prog->stats, cpu);
2395 		do {
2396 			start = u64_stats_fetch_begin(&st->syncp);
2397 			tnsecs = u64_stats_read(&st->nsecs);
2398 			tcnt = u64_stats_read(&st->cnt);
2399 			tmisses = u64_stats_read(&st->misses);
2400 		} while (u64_stats_fetch_retry(&st->syncp, start));
2401 		nsecs += tnsecs;
2402 		cnt += tcnt;
2403 		misses += tmisses;
2404 	}
2405 	stats->nsecs = nsecs;
2406 	stats->cnt = cnt;
2407 	stats->misses = misses;
2408 }
2409 
2410 #ifdef CONFIG_PROC_FS
2411 static void bpf_prog_show_fdinfo(struct seq_file *m, struct file *filp)
2412 {
2413 	const struct bpf_prog *prog = filp->private_data;
2414 	char prog_tag[sizeof(prog->tag) * 2 + 1] = { };
2415 	struct bpf_prog_kstats stats;
2416 
2417 	bpf_prog_get_stats(prog, &stats);
2418 	bin2hex(prog_tag, prog->tag, sizeof(prog->tag));
2419 	seq_printf(m,
2420 		   "prog_type:\t%u\n"
2421 		   "prog_jited:\t%u\n"
2422 		   "prog_tag:\t%s\n"
2423 		   "memlock:\t%llu\n"
2424 		   "prog_id:\t%u\n"
2425 		   "run_time_ns:\t%llu\n"
2426 		   "run_cnt:\t%llu\n"
2427 		   "recursion_misses:\t%llu\n"
2428 		   "verified_insns:\t%u\n",
2429 		   prog->type,
2430 		   prog->jited,
2431 		   prog_tag,
2432 		   prog->pages * 1ULL << PAGE_SHIFT,
2433 		   prog->aux->id,
2434 		   stats.nsecs,
2435 		   stats.cnt,
2436 		   stats.misses,
2437 		   prog->aux->verified_insns);
2438 }
2439 #endif
2440 
2441 const struct file_operations bpf_prog_fops = {
2442 #ifdef CONFIG_PROC_FS
2443 	.show_fdinfo	= bpf_prog_show_fdinfo,
2444 #endif
2445 	.release	= bpf_prog_release,
2446 	.read		= bpf_dummy_read,
2447 	.write		= bpf_dummy_write,
2448 };
2449 
2450 int bpf_prog_new_fd(struct bpf_prog *prog)
2451 {
2452 	int ret;
2453 
2454 	ret = security_bpf_prog(prog);
2455 	if (ret < 0)
2456 		return ret;
2457 
2458 	return anon_inode_getfd("bpf-prog", &bpf_prog_fops, prog,
2459 				O_RDWR | O_CLOEXEC);
2460 }
2461 
2462 void bpf_prog_add(struct bpf_prog *prog, int i)
2463 {
2464 	atomic64_add(i, &prog->aux->refcnt);
2465 }
2466 EXPORT_SYMBOL_GPL(bpf_prog_add);
2467 
2468 void bpf_prog_sub(struct bpf_prog *prog, int i)
2469 {
2470 	/* Only to be used for undoing previous bpf_prog_add() in some
2471 	 * error path. We still know that another entity in our call
2472 	 * path holds a reference to the program, thus atomic_sub() can
2473 	 * be safely used in such cases!
2474 	 */
2475 	WARN_ON(atomic64_sub_return(i, &prog->aux->refcnt) == 0);
2476 }
2477 EXPORT_SYMBOL_GPL(bpf_prog_sub);
2478 
2479 void bpf_prog_inc(struct bpf_prog *prog)
2480 {
2481 	atomic64_inc(&prog->aux->refcnt);
2482 }
2483 EXPORT_SYMBOL_GPL(bpf_prog_inc);
2484 
2485 /* prog_idr_lock should have been held */
2486 struct bpf_prog *bpf_prog_inc_not_zero(struct bpf_prog *prog)
2487 {
2488 	int refold;
2489 
2490 	refold = atomic64_fetch_add_unless(&prog->aux->refcnt, 1, 0);
2491 
2492 	if (!refold)
2493 		return ERR_PTR(-ENOENT);
2494 
2495 	return prog;
2496 }
2497 EXPORT_SYMBOL_GPL(bpf_prog_inc_not_zero);
2498 
2499 bool bpf_prog_get_ok(struct bpf_prog *prog,
2500 			    enum bpf_prog_type *attach_type, bool attach_drv)
2501 {
2502 	/* not an attachment, just a refcount inc, always allow */
2503 	if (!attach_type)
2504 		return true;
2505 
2506 	if (prog->type != *attach_type)
2507 		return false;
2508 	if (bpf_prog_is_offloaded(prog->aux) && !attach_drv)
2509 		return false;
2510 
2511 	return true;
2512 }
2513 
2514 static struct bpf_prog *__bpf_prog_get(u32 ufd, enum bpf_prog_type *attach_type,
2515 				       bool attach_drv)
2516 {
2517 	CLASS(fd, f)(ufd);
2518 	struct bpf_prog *prog;
2519 
2520 	if (fd_empty(f))
2521 		return ERR_PTR(-EBADF);
2522 	if (fd_file(f)->f_op != &bpf_prog_fops)
2523 		return ERR_PTR(-EINVAL);
2524 
2525 	prog = fd_file(f)->private_data;
2526 	if (!bpf_prog_get_ok(prog, attach_type, attach_drv))
2527 		return ERR_PTR(-EINVAL);
2528 
2529 	bpf_prog_inc(prog);
2530 	return prog;
2531 }
2532 
2533 struct bpf_prog *bpf_prog_get(u32 ufd)
2534 {
2535 	return __bpf_prog_get(ufd, NULL, false);
2536 }
2537 
2538 struct bpf_prog *bpf_prog_get_type_dev(u32 ufd, enum bpf_prog_type type,
2539 				       bool attach_drv)
2540 {
2541 	return __bpf_prog_get(ufd, &type, attach_drv);
2542 }
2543 EXPORT_SYMBOL_GPL(bpf_prog_get_type_dev);
2544 
2545 /* Initially all BPF programs could be loaded w/o specifying
2546  * expected_attach_type. Later for some of them specifying expected_attach_type
2547  * at load time became required so that program could be validated properly.
2548  * Programs of types that are allowed to be loaded both w/ and w/o (for
2549  * backward compatibility) expected_attach_type, should have the default attach
2550  * type assigned to expected_attach_type for the latter case, so that it can be
2551  * validated later at attach time.
2552  *
2553  * bpf_prog_load_fixup_attach_type() sets expected_attach_type in @attr if
2554  * prog type requires it but has some attach types that have to be backward
2555  * compatible.
2556  */
2557 static void bpf_prog_load_fixup_attach_type(union bpf_attr *attr)
2558 {
2559 	switch (attr->prog_type) {
2560 	case BPF_PROG_TYPE_CGROUP_SOCK:
2561 		/* Unfortunately BPF_ATTACH_TYPE_UNSPEC enumeration doesn't
2562 		 * exist so checking for non-zero is the way to go here.
2563 		 */
2564 		if (!attr->expected_attach_type)
2565 			attr->expected_attach_type =
2566 				BPF_CGROUP_INET_SOCK_CREATE;
2567 		break;
2568 	case BPF_PROG_TYPE_SK_REUSEPORT:
2569 		if (!attr->expected_attach_type)
2570 			attr->expected_attach_type =
2571 				BPF_SK_REUSEPORT_SELECT;
2572 		break;
2573 	}
2574 }
2575 
2576 static int
2577 bpf_prog_load_check_attach(enum bpf_prog_type prog_type,
2578 			   enum bpf_attach_type expected_attach_type,
2579 			   struct btf *attach_btf, u32 btf_id,
2580 			   struct bpf_prog *dst_prog)
2581 {
2582 	if (btf_id) {
2583 		if (btf_id > BTF_MAX_TYPE)
2584 			return -EINVAL;
2585 
2586 		if (!attach_btf && !dst_prog)
2587 			return -EINVAL;
2588 
2589 		switch (prog_type) {
2590 		case BPF_PROG_TYPE_TRACING:
2591 		case BPF_PROG_TYPE_LSM:
2592 		case BPF_PROG_TYPE_STRUCT_OPS:
2593 		case BPF_PROG_TYPE_EXT:
2594 			break;
2595 		default:
2596 			return -EINVAL;
2597 		}
2598 	}
2599 
2600 	if (attach_btf && (!btf_id || dst_prog))
2601 		return -EINVAL;
2602 
2603 	if (dst_prog && prog_type != BPF_PROG_TYPE_TRACING &&
2604 	    prog_type != BPF_PROG_TYPE_EXT)
2605 		return -EINVAL;
2606 
2607 	switch (prog_type) {
2608 	case BPF_PROG_TYPE_CGROUP_SOCK:
2609 		switch (expected_attach_type) {
2610 		case BPF_CGROUP_INET_SOCK_CREATE:
2611 		case BPF_CGROUP_INET_SOCK_RELEASE:
2612 		case BPF_CGROUP_INET4_POST_BIND:
2613 		case BPF_CGROUP_INET6_POST_BIND:
2614 			return 0;
2615 		default:
2616 			return -EINVAL;
2617 		}
2618 	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
2619 		switch (expected_attach_type) {
2620 		case BPF_CGROUP_INET4_BIND:
2621 		case BPF_CGROUP_INET6_BIND:
2622 		case BPF_CGROUP_INET4_CONNECT:
2623 		case BPF_CGROUP_INET6_CONNECT:
2624 		case BPF_CGROUP_UNIX_CONNECT:
2625 		case BPF_CGROUP_INET4_GETPEERNAME:
2626 		case BPF_CGROUP_INET6_GETPEERNAME:
2627 		case BPF_CGROUP_UNIX_GETPEERNAME:
2628 		case BPF_CGROUP_INET4_GETSOCKNAME:
2629 		case BPF_CGROUP_INET6_GETSOCKNAME:
2630 		case BPF_CGROUP_UNIX_GETSOCKNAME:
2631 		case BPF_CGROUP_UDP4_SENDMSG:
2632 		case BPF_CGROUP_UDP6_SENDMSG:
2633 		case BPF_CGROUP_UNIX_SENDMSG:
2634 		case BPF_CGROUP_UDP4_RECVMSG:
2635 		case BPF_CGROUP_UDP6_RECVMSG:
2636 		case BPF_CGROUP_UNIX_RECVMSG:
2637 			return 0;
2638 		default:
2639 			return -EINVAL;
2640 		}
2641 	case BPF_PROG_TYPE_CGROUP_SKB:
2642 		switch (expected_attach_type) {
2643 		case BPF_CGROUP_INET_INGRESS:
2644 		case BPF_CGROUP_INET_EGRESS:
2645 			return 0;
2646 		default:
2647 			return -EINVAL;
2648 		}
2649 	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
2650 		switch (expected_attach_type) {
2651 		case BPF_CGROUP_SETSOCKOPT:
2652 		case BPF_CGROUP_GETSOCKOPT:
2653 			return 0;
2654 		default:
2655 			return -EINVAL;
2656 		}
2657 	case BPF_PROG_TYPE_SK_LOOKUP:
2658 		if (expected_attach_type == BPF_SK_LOOKUP)
2659 			return 0;
2660 		return -EINVAL;
2661 	case BPF_PROG_TYPE_SK_REUSEPORT:
2662 		switch (expected_attach_type) {
2663 		case BPF_SK_REUSEPORT_SELECT:
2664 		case BPF_SK_REUSEPORT_SELECT_OR_MIGRATE:
2665 			return 0;
2666 		default:
2667 			return -EINVAL;
2668 		}
2669 	case BPF_PROG_TYPE_NETFILTER:
2670 		if (expected_attach_type == BPF_NETFILTER)
2671 			return 0;
2672 		return -EINVAL;
2673 	case BPF_PROG_TYPE_SYSCALL:
2674 	case BPF_PROG_TYPE_EXT:
2675 		if (expected_attach_type)
2676 			return -EINVAL;
2677 		fallthrough;
2678 	default:
2679 		return 0;
2680 	}
2681 }
2682 
2683 static bool is_net_admin_prog_type(enum bpf_prog_type prog_type)
2684 {
2685 	switch (prog_type) {
2686 	case BPF_PROG_TYPE_SCHED_CLS:
2687 	case BPF_PROG_TYPE_SCHED_ACT:
2688 	case BPF_PROG_TYPE_XDP:
2689 	case BPF_PROG_TYPE_LWT_IN:
2690 	case BPF_PROG_TYPE_LWT_OUT:
2691 	case BPF_PROG_TYPE_LWT_XMIT:
2692 	case BPF_PROG_TYPE_LWT_SEG6LOCAL:
2693 	case BPF_PROG_TYPE_SK_SKB:
2694 	case BPF_PROG_TYPE_SK_MSG:
2695 	case BPF_PROG_TYPE_FLOW_DISSECTOR:
2696 	case BPF_PROG_TYPE_CGROUP_DEVICE:
2697 	case BPF_PROG_TYPE_CGROUP_SOCK:
2698 	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
2699 	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
2700 	case BPF_PROG_TYPE_CGROUP_SYSCTL:
2701 	case BPF_PROG_TYPE_SOCK_OPS:
2702 	case BPF_PROG_TYPE_EXT: /* extends any prog */
2703 	case BPF_PROG_TYPE_NETFILTER:
2704 		return true;
2705 	case BPF_PROG_TYPE_CGROUP_SKB:
2706 		/* always unpriv */
2707 	case BPF_PROG_TYPE_SK_REUSEPORT:
2708 		/* equivalent to SOCKET_FILTER. need CAP_BPF only */
2709 	default:
2710 		return false;
2711 	}
2712 }
2713 
2714 static bool is_perfmon_prog_type(enum bpf_prog_type prog_type)
2715 {
2716 	switch (prog_type) {
2717 	case BPF_PROG_TYPE_KPROBE:
2718 	case BPF_PROG_TYPE_TRACEPOINT:
2719 	case BPF_PROG_TYPE_PERF_EVENT:
2720 	case BPF_PROG_TYPE_RAW_TRACEPOINT:
2721 	case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE:
2722 	case BPF_PROG_TYPE_TRACING:
2723 	case BPF_PROG_TYPE_LSM:
2724 	case BPF_PROG_TYPE_STRUCT_OPS: /* has access to struct sock */
2725 	case BPF_PROG_TYPE_EXT: /* extends any prog */
2726 		return true;
2727 	default:
2728 		return false;
2729 	}
2730 }
2731 
2732 /* last field in 'union bpf_attr' used by this command */
2733 #define BPF_PROG_LOAD_LAST_FIELD prog_token_fd
2734 
2735 static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr, u32 uattr_size)
2736 {
2737 	enum bpf_prog_type type = attr->prog_type;
2738 	struct bpf_prog *prog, *dst_prog = NULL;
2739 	struct btf *attach_btf = NULL;
2740 	struct bpf_token *token = NULL;
2741 	bool bpf_cap;
2742 	int err;
2743 	char license[128];
2744 
2745 	if (CHECK_ATTR(BPF_PROG_LOAD))
2746 		return -EINVAL;
2747 
2748 	if (attr->prog_flags & ~(BPF_F_STRICT_ALIGNMENT |
2749 				 BPF_F_ANY_ALIGNMENT |
2750 				 BPF_F_TEST_STATE_FREQ |
2751 				 BPF_F_SLEEPABLE |
2752 				 BPF_F_TEST_RND_HI32 |
2753 				 BPF_F_XDP_HAS_FRAGS |
2754 				 BPF_F_XDP_DEV_BOUND_ONLY |
2755 				 BPF_F_TEST_REG_INVARIANTS |
2756 				 BPF_F_TOKEN_FD))
2757 		return -EINVAL;
2758 
2759 	bpf_prog_load_fixup_attach_type(attr);
2760 
2761 	if (attr->prog_flags & BPF_F_TOKEN_FD) {
2762 		token = bpf_token_get_from_fd(attr->prog_token_fd);
2763 		if (IS_ERR(token))
2764 			return PTR_ERR(token);
2765 		/* if current token doesn't grant prog loading permissions,
2766 		 * then we can't use this token, so ignore it and rely on
2767 		 * system-wide capabilities checks
2768 		 */
2769 		if (!bpf_token_allow_cmd(token, BPF_PROG_LOAD) ||
2770 		    !bpf_token_allow_prog_type(token, attr->prog_type,
2771 					       attr->expected_attach_type)) {
2772 			bpf_token_put(token);
2773 			token = NULL;
2774 		}
2775 	}
2776 
2777 	bpf_cap = bpf_token_capable(token, CAP_BPF);
2778 	err = -EPERM;
2779 
2780 	if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) &&
2781 	    (attr->prog_flags & BPF_F_ANY_ALIGNMENT) &&
2782 	    !bpf_cap)
2783 		goto put_token;
2784 
2785 	/* Intent here is for unprivileged_bpf_disabled to block BPF program
2786 	 * creation for unprivileged users; other actions depend
2787 	 * on fd availability and access to bpffs, so are dependent on
2788 	 * object creation success. Even with unprivileged BPF disabled,
2789 	 * capability checks are still carried out for these
2790 	 * and other operations.
2791 	 */
2792 	if (sysctl_unprivileged_bpf_disabled && !bpf_cap)
2793 		goto put_token;
2794 
2795 	if (attr->insn_cnt == 0 ||
2796 	    attr->insn_cnt > (bpf_cap ? BPF_COMPLEXITY_LIMIT_INSNS : BPF_MAXINSNS)) {
2797 		err = -E2BIG;
2798 		goto put_token;
2799 	}
2800 	if (type != BPF_PROG_TYPE_SOCKET_FILTER &&
2801 	    type != BPF_PROG_TYPE_CGROUP_SKB &&
2802 	    !bpf_cap)
2803 		goto put_token;
2804 
2805 	if (is_net_admin_prog_type(type) && !bpf_token_capable(token, CAP_NET_ADMIN))
2806 		goto put_token;
2807 	if (is_perfmon_prog_type(type) && !bpf_token_capable(token, CAP_PERFMON))
2808 		goto put_token;
2809 
2810 	/* attach_prog_fd/attach_btf_obj_fd can specify fd of either bpf_prog
2811 	 * or btf, we need to check which one it is
2812 	 */
2813 	if (attr->attach_prog_fd) {
2814 		dst_prog = bpf_prog_get(attr->attach_prog_fd);
2815 		if (IS_ERR(dst_prog)) {
2816 			dst_prog = NULL;
2817 			attach_btf = btf_get_by_fd(attr->attach_btf_obj_fd);
2818 			if (IS_ERR(attach_btf)) {
2819 				err = -EINVAL;
2820 				goto put_token;
2821 			}
2822 			if (!btf_is_kernel(attach_btf)) {
2823 				/* attaching through specifying bpf_prog's BTF
2824 				 * objects directly might be supported eventually
2825 				 */
2826 				btf_put(attach_btf);
2827 				err = -ENOTSUPP;
2828 				goto put_token;
2829 			}
2830 		}
2831 	} else if (attr->attach_btf_id) {
2832 		/* fall back to vmlinux BTF, if BTF type ID is specified */
2833 		attach_btf = bpf_get_btf_vmlinux();
2834 		if (IS_ERR(attach_btf)) {
2835 			err = PTR_ERR(attach_btf);
2836 			goto put_token;
2837 		}
2838 		if (!attach_btf) {
2839 			err = -EINVAL;
2840 			goto put_token;
2841 		}
2842 		btf_get(attach_btf);
2843 	}
2844 
2845 	if (bpf_prog_load_check_attach(type, attr->expected_attach_type,
2846 				       attach_btf, attr->attach_btf_id,
2847 				       dst_prog)) {
2848 		if (dst_prog)
2849 			bpf_prog_put(dst_prog);
2850 		if (attach_btf)
2851 			btf_put(attach_btf);
2852 		err = -EINVAL;
2853 		goto put_token;
2854 	}
2855 
2856 	/* plain bpf_prog allocation */
2857 	prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER);
2858 	if (!prog) {
2859 		if (dst_prog)
2860 			bpf_prog_put(dst_prog);
2861 		if (attach_btf)
2862 			btf_put(attach_btf);
2863 		err = -EINVAL;
2864 		goto put_token;
2865 	}
2866 
2867 	prog->expected_attach_type = attr->expected_attach_type;
2868 	prog->sleepable = !!(attr->prog_flags & BPF_F_SLEEPABLE);
2869 	prog->aux->attach_btf = attach_btf;
2870 	prog->aux->attach_btf_id = attr->attach_btf_id;
2871 	prog->aux->dst_prog = dst_prog;
2872 	prog->aux->dev_bound = !!attr->prog_ifindex;
2873 	prog->aux->xdp_has_frags = attr->prog_flags & BPF_F_XDP_HAS_FRAGS;
2874 
2875 	/* move token into prog->aux, reuse taken refcnt */
2876 	prog->aux->token = token;
2877 	token = NULL;
2878 
2879 	prog->aux->user = get_current_user();
2880 	prog->len = attr->insn_cnt;
2881 
2882 	err = -EFAULT;
2883 	if (copy_from_bpfptr(prog->insns,
2884 			     make_bpfptr(attr->insns, uattr.is_kernel),
2885 			     bpf_prog_insn_size(prog)) != 0)
2886 		goto free_prog;
2887 	/* copy eBPF program license from user space */
2888 	if (strncpy_from_bpfptr(license,
2889 				make_bpfptr(attr->license, uattr.is_kernel),
2890 				sizeof(license) - 1) < 0)
2891 		goto free_prog;
2892 	license[sizeof(license) - 1] = 0;
2893 
2894 	/* eBPF programs must be GPL compatible to use GPL-ed functions */
2895 	prog->gpl_compatible = license_is_gpl_compatible(license) ? 1 : 0;
2896 
2897 	prog->orig_prog = NULL;
2898 	prog->jited = 0;
2899 
2900 	atomic64_set(&prog->aux->refcnt, 1);
2901 
2902 	if (bpf_prog_is_dev_bound(prog->aux)) {
2903 		err = bpf_prog_dev_bound_init(prog, attr);
2904 		if (err)
2905 			goto free_prog;
2906 	}
2907 
2908 	if (type == BPF_PROG_TYPE_EXT && dst_prog &&
2909 	    bpf_prog_is_dev_bound(dst_prog->aux)) {
2910 		err = bpf_prog_dev_bound_inherit(prog, dst_prog);
2911 		if (err)
2912 			goto free_prog;
2913 	}
2914 
2915 	/*
2916 	 * Bookkeeping for managing the program attachment chain.
2917 	 *
2918 	 * It might be tempting to set attach_tracing_prog flag at the attachment
2919 	 * time, but this will not prevent from loading bunch of tracing prog
2920 	 * first, then attach them one to another.
2921 	 *
2922 	 * The flag attach_tracing_prog is set for the whole program lifecycle, and
2923 	 * doesn't have to be cleared in bpf_tracing_link_release, since tracing
2924 	 * programs cannot change attachment target.
2925 	 */
2926 	if (type == BPF_PROG_TYPE_TRACING && dst_prog &&
2927 	    dst_prog->type == BPF_PROG_TYPE_TRACING) {
2928 		prog->aux->attach_tracing_prog = true;
2929 	}
2930 
2931 	/* find program type: socket_filter vs tracing_filter */
2932 	err = find_prog_type(type, prog);
2933 	if (err < 0)
2934 		goto free_prog;
2935 
2936 	prog->aux->load_time = ktime_get_boottime_ns();
2937 	err = bpf_obj_name_cpy(prog->aux->name, attr->prog_name,
2938 			       sizeof(attr->prog_name));
2939 	if (err < 0)
2940 		goto free_prog;
2941 
2942 	err = security_bpf_prog_load(prog, attr, token);
2943 	if (err)
2944 		goto free_prog_sec;
2945 
2946 	/* run eBPF verifier */
2947 	err = bpf_check(&prog, attr, uattr, uattr_size);
2948 	if (err < 0)
2949 		goto free_used_maps;
2950 
2951 	prog = bpf_prog_select_runtime(prog, &err);
2952 	if (err < 0)
2953 		goto free_used_maps;
2954 
2955 	err = bpf_prog_alloc_id(prog);
2956 	if (err)
2957 		goto free_used_maps;
2958 
2959 	/* Upon success of bpf_prog_alloc_id(), the BPF prog is
2960 	 * effectively publicly exposed. However, retrieving via
2961 	 * bpf_prog_get_fd_by_id() will take another reference,
2962 	 * therefore it cannot be gone underneath us.
2963 	 *
2964 	 * Only for the time /after/ successful bpf_prog_new_fd()
2965 	 * and before returning to userspace, we might just hold
2966 	 * one reference and any parallel close on that fd could
2967 	 * rip everything out. Hence, below notifications must
2968 	 * happen before bpf_prog_new_fd().
2969 	 *
2970 	 * Also, any failure handling from this point onwards must
2971 	 * be using bpf_prog_put() given the program is exposed.
2972 	 */
2973 	bpf_prog_kallsyms_add(prog);
2974 	perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_LOAD, 0);
2975 	bpf_audit_prog(prog, BPF_AUDIT_LOAD);
2976 
2977 	err = bpf_prog_new_fd(prog);
2978 	if (err < 0)
2979 		bpf_prog_put(prog);
2980 	return err;
2981 
2982 free_used_maps:
2983 	/* In case we have subprogs, we need to wait for a grace
2984 	 * period before we can tear down JIT memory since symbols
2985 	 * are already exposed under kallsyms.
2986 	 */
2987 	__bpf_prog_put_noref(prog, prog->aux->real_func_cnt);
2988 	return err;
2989 
2990 free_prog_sec:
2991 	security_bpf_prog_free(prog);
2992 free_prog:
2993 	free_uid(prog->aux->user);
2994 	if (prog->aux->attach_btf)
2995 		btf_put(prog->aux->attach_btf);
2996 	bpf_prog_free(prog);
2997 put_token:
2998 	bpf_token_put(token);
2999 	return err;
3000 }
3001 
3002 #define BPF_OBJ_LAST_FIELD path_fd
3003 
3004 static int bpf_obj_pin(const union bpf_attr *attr)
3005 {
3006 	int path_fd;
3007 
3008 	if (CHECK_ATTR(BPF_OBJ) || attr->file_flags & ~BPF_F_PATH_FD)
3009 		return -EINVAL;
3010 
3011 	/* path_fd has to be accompanied by BPF_F_PATH_FD flag */
3012 	if (!(attr->file_flags & BPF_F_PATH_FD) && attr->path_fd)
3013 		return -EINVAL;
3014 
3015 	path_fd = attr->file_flags & BPF_F_PATH_FD ? attr->path_fd : AT_FDCWD;
3016 	return bpf_obj_pin_user(attr->bpf_fd, path_fd,
3017 				u64_to_user_ptr(attr->pathname));
3018 }
3019 
3020 static int bpf_obj_get(const union bpf_attr *attr)
3021 {
3022 	int path_fd;
3023 
3024 	if (CHECK_ATTR(BPF_OBJ) || attr->bpf_fd != 0 ||
3025 	    attr->file_flags & ~(BPF_OBJ_FLAG_MASK | BPF_F_PATH_FD))
3026 		return -EINVAL;
3027 
3028 	/* path_fd has to be accompanied by BPF_F_PATH_FD flag */
3029 	if (!(attr->file_flags & BPF_F_PATH_FD) && attr->path_fd)
3030 		return -EINVAL;
3031 
3032 	path_fd = attr->file_flags & BPF_F_PATH_FD ? attr->path_fd : AT_FDCWD;
3033 	return bpf_obj_get_user(path_fd, u64_to_user_ptr(attr->pathname),
3034 				attr->file_flags);
3035 }
3036 
3037 /* bpf_link_init_sleepable() allows to specify whether BPF link itself has
3038  * "sleepable" semantics, which normally would mean that BPF link's attach
3039  * hook can dereference link or link's underlying program for some time after
3040  * detachment due to RCU Tasks Trace-based lifetime protection scheme.
3041  * BPF program itself can be non-sleepable, yet, because it's transitively
3042  * reachable through BPF link, its freeing has to be delayed until after RCU
3043  * Tasks Trace GP.
3044  */
3045 void bpf_link_init_sleepable(struct bpf_link *link, enum bpf_link_type type,
3046 			     const struct bpf_link_ops *ops, struct bpf_prog *prog,
3047 			     bool sleepable)
3048 {
3049 	WARN_ON(ops->dealloc && ops->dealloc_deferred);
3050 	atomic64_set(&link->refcnt, 1);
3051 	link->type = type;
3052 	link->sleepable = sleepable;
3053 	link->id = 0;
3054 	link->ops = ops;
3055 	link->prog = prog;
3056 }
3057 
3058 void bpf_link_init(struct bpf_link *link, enum bpf_link_type type,
3059 		   const struct bpf_link_ops *ops, struct bpf_prog *prog)
3060 {
3061 	bpf_link_init_sleepable(link, type, ops, prog, false);
3062 }
3063 
3064 static void bpf_link_free_id(int id)
3065 {
3066 	if (!id)
3067 		return;
3068 
3069 	spin_lock_bh(&link_idr_lock);
3070 	idr_remove(&link_idr, id);
3071 	spin_unlock_bh(&link_idr_lock);
3072 }
3073 
3074 /* Clean up bpf_link and corresponding anon_inode file and FD. After
3075  * anon_inode is created, bpf_link can't be just kfree()'d due to deferred
3076  * anon_inode's release() call. This helper marks bpf_link as
3077  * defunct, releases anon_inode file and puts reserved FD. bpf_prog's refcnt
3078  * is not decremented, it's the responsibility of a calling code that failed
3079  * to complete bpf_link initialization.
3080  * This helper eventually calls link's dealloc callback, but does not call
3081  * link's release callback.
3082  */
3083 void bpf_link_cleanup(struct bpf_link_primer *primer)
3084 {
3085 	primer->link->prog = NULL;
3086 	bpf_link_free_id(primer->id);
3087 	fput(primer->file);
3088 	put_unused_fd(primer->fd);
3089 }
3090 
3091 void bpf_link_inc(struct bpf_link *link)
3092 {
3093 	atomic64_inc(&link->refcnt);
3094 }
3095 
3096 static void bpf_link_dealloc(struct bpf_link *link)
3097 {
3098 	/* now that we know that bpf_link itself can't be reached, put underlying BPF program */
3099 	if (link->prog)
3100 		bpf_prog_put(link->prog);
3101 
3102 	/* free bpf_link and its containing memory */
3103 	if (link->ops->dealloc_deferred)
3104 		link->ops->dealloc_deferred(link);
3105 	else
3106 		link->ops->dealloc(link);
3107 }
3108 
3109 static void bpf_link_defer_dealloc_rcu_gp(struct rcu_head *rcu)
3110 {
3111 	struct bpf_link *link = container_of(rcu, struct bpf_link, rcu);
3112 
3113 	bpf_link_dealloc(link);
3114 }
3115 
3116 static void bpf_link_defer_dealloc_mult_rcu_gp(struct rcu_head *rcu)
3117 {
3118 	if (rcu_trace_implies_rcu_gp())
3119 		bpf_link_defer_dealloc_rcu_gp(rcu);
3120 	else
3121 		call_rcu(rcu, bpf_link_defer_dealloc_rcu_gp);
3122 }
3123 
3124 /* bpf_link_free is guaranteed to be called from process context */
3125 static void bpf_link_free(struct bpf_link *link)
3126 {
3127 	const struct bpf_link_ops *ops = link->ops;
3128 
3129 	bpf_link_free_id(link->id);
3130 	/* detach BPF program, clean up used resources */
3131 	if (link->prog)
3132 		ops->release(link);
3133 	if (ops->dealloc_deferred) {
3134 		/* Schedule BPF link deallocation, which will only then
3135 		 * trigger putting BPF program refcount.
3136 		 * If underlying BPF program is sleepable or BPF link's target
3137 		 * attach hookpoint is sleepable or otherwise requires RCU GPs
3138 		 * to ensure link and its underlying BPF program is not
3139 		 * reachable anymore, we need to first wait for RCU tasks
3140 		 * trace sync, and then go through "classic" RCU grace period
3141 		 */
3142 		if (link->sleepable || (link->prog && link->prog->sleepable))
3143 			call_rcu_tasks_trace(&link->rcu, bpf_link_defer_dealloc_mult_rcu_gp);
3144 		else
3145 			call_rcu(&link->rcu, bpf_link_defer_dealloc_rcu_gp);
3146 	} else if (ops->dealloc) {
3147 		bpf_link_dealloc(link);
3148 	}
3149 }
3150 
3151 static void bpf_link_put_deferred(struct work_struct *work)
3152 {
3153 	struct bpf_link *link = container_of(work, struct bpf_link, work);
3154 
3155 	bpf_link_free(link);
3156 }
3157 
3158 /* bpf_link_put might be called from atomic context. It needs to be called
3159  * from sleepable context in order to acquire sleeping locks during the process.
3160  */
3161 void bpf_link_put(struct bpf_link *link)
3162 {
3163 	if (!atomic64_dec_and_test(&link->refcnt))
3164 		return;
3165 
3166 	INIT_WORK(&link->work, bpf_link_put_deferred);
3167 	schedule_work(&link->work);
3168 }
3169 EXPORT_SYMBOL(bpf_link_put);
3170 
3171 static void bpf_link_put_direct(struct bpf_link *link)
3172 {
3173 	if (!atomic64_dec_and_test(&link->refcnt))
3174 		return;
3175 	bpf_link_free(link);
3176 }
3177 
3178 static int bpf_link_release(struct inode *inode, struct file *filp)
3179 {
3180 	struct bpf_link *link = filp->private_data;
3181 
3182 	bpf_link_put_direct(link);
3183 	return 0;
3184 }
3185 
3186 #ifdef CONFIG_PROC_FS
3187 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type)
3188 #define BPF_MAP_TYPE(_id, _ops)
3189 #define BPF_LINK_TYPE(_id, _name) [_id] = #_name,
3190 static const char *bpf_link_type_strs[] = {
3191 	[BPF_LINK_TYPE_UNSPEC] = "<invalid>",
3192 #include <linux/bpf_types.h>
3193 };
3194 #undef BPF_PROG_TYPE
3195 #undef BPF_MAP_TYPE
3196 #undef BPF_LINK_TYPE
3197 
3198 static void bpf_link_show_fdinfo(struct seq_file *m, struct file *filp)
3199 {
3200 	const struct bpf_link *link = filp->private_data;
3201 	const struct bpf_prog *prog = link->prog;
3202 	enum bpf_link_type type = link->type;
3203 	char prog_tag[sizeof(prog->tag) * 2 + 1] = { };
3204 
3205 	if (type < ARRAY_SIZE(bpf_link_type_strs) && bpf_link_type_strs[type]) {
3206 		seq_printf(m, "link_type:\t%s\n", bpf_link_type_strs[type]);
3207 	} else {
3208 		WARN_ONCE(1, "missing BPF_LINK_TYPE(...) for link type %u\n", type);
3209 		seq_printf(m, "link_type:\t<%u>\n", type);
3210 	}
3211 	seq_printf(m, "link_id:\t%u\n", link->id);
3212 
3213 	if (prog) {
3214 		bin2hex(prog_tag, prog->tag, sizeof(prog->tag));
3215 		seq_printf(m,
3216 			   "prog_tag:\t%s\n"
3217 			   "prog_id:\t%u\n",
3218 			   prog_tag,
3219 			   prog->aux->id);
3220 	}
3221 	if (link->ops->show_fdinfo)
3222 		link->ops->show_fdinfo(link, m);
3223 }
3224 #endif
3225 
3226 static __poll_t bpf_link_poll(struct file *file, struct poll_table_struct *pts)
3227 {
3228 	struct bpf_link *link = file->private_data;
3229 
3230 	return link->ops->poll(file, pts);
3231 }
3232 
3233 static const struct file_operations bpf_link_fops = {
3234 #ifdef CONFIG_PROC_FS
3235 	.show_fdinfo	= bpf_link_show_fdinfo,
3236 #endif
3237 	.release	= bpf_link_release,
3238 	.read		= bpf_dummy_read,
3239 	.write		= bpf_dummy_write,
3240 };
3241 
3242 static const struct file_operations bpf_link_fops_poll = {
3243 #ifdef CONFIG_PROC_FS
3244 	.show_fdinfo	= bpf_link_show_fdinfo,
3245 #endif
3246 	.release	= bpf_link_release,
3247 	.read		= bpf_dummy_read,
3248 	.write		= bpf_dummy_write,
3249 	.poll		= bpf_link_poll,
3250 };
3251 
3252 static int bpf_link_alloc_id(struct bpf_link *link)
3253 {
3254 	int id;
3255 
3256 	idr_preload(GFP_KERNEL);
3257 	spin_lock_bh(&link_idr_lock);
3258 	id = idr_alloc_cyclic(&link_idr, link, 1, INT_MAX, GFP_ATOMIC);
3259 	spin_unlock_bh(&link_idr_lock);
3260 	idr_preload_end();
3261 
3262 	return id;
3263 }
3264 
3265 /* Prepare bpf_link to be exposed to user-space by allocating anon_inode file,
3266  * reserving unused FD and allocating ID from link_idr. This is to be paired
3267  * with bpf_link_settle() to install FD and ID and expose bpf_link to
3268  * user-space, if bpf_link is successfully attached. If not, bpf_link and
3269  * pre-allocated resources are to be freed with bpf_cleanup() call. All the
3270  * transient state is passed around in struct bpf_link_primer.
3271  * This is preferred way to create and initialize bpf_link, especially when
3272  * there are complicated and expensive operations in between creating bpf_link
3273  * itself and attaching it to BPF hook. By using bpf_link_prime() and
3274  * bpf_link_settle() kernel code using bpf_link doesn't have to perform
3275  * expensive (and potentially failing) roll back operations in a rare case
3276  * that file, FD, or ID can't be allocated.
3277  */
3278 int bpf_link_prime(struct bpf_link *link, struct bpf_link_primer *primer)
3279 {
3280 	struct file *file;
3281 	int fd, id;
3282 
3283 	fd = get_unused_fd_flags(O_CLOEXEC);
3284 	if (fd < 0)
3285 		return fd;
3286 
3287 
3288 	id = bpf_link_alloc_id(link);
3289 	if (id < 0) {
3290 		put_unused_fd(fd);
3291 		return id;
3292 	}
3293 
3294 	file = anon_inode_getfile("bpf_link",
3295 				  link->ops->poll ? &bpf_link_fops_poll : &bpf_link_fops,
3296 				  link, O_CLOEXEC);
3297 	if (IS_ERR(file)) {
3298 		bpf_link_free_id(id);
3299 		put_unused_fd(fd);
3300 		return PTR_ERR(file);
3301 	}
3302 
3303 	primer->link = link;
3304 	primer->file = file;
3305 	primer->fd = fd;
3306 	primer->id = id;
3307 	return 0;
3308 }
3309 
3310 int bpf_link_settle(struct bpf_link_primer *primer)
3311 {
3312 	/* make bpf_link fetchable by ID */
3313 	spin_lock_bh(&link_idr_lock);
3314 	primer->link->id = primer->id;
3315 	spin_unlock_bh(&link_idr_lock);
3316 	/* make bpf_link fetchable by FD */
3317 	fd_install(primer->fd, primer->file);
3318 	/* pass through installed FD */
3319 	return primer->fd;
3320 }
3321 
3322 int bpf_link_new_fd(struct bpf_link *link)
3323 {
3324 	return anon_inode_getfd("bpf-link",
3325 				link->ops->poll ? &bpf_link_fops_poll : &bpf_link_fops,
3326 				link, O_CLOEXEC);
3327 }
3328 
3329 struct bpf_link *bpf_link_get_from_fd(u32 ufd)
3330 {
3331 	CLASS(fd, f)(ufd);
3332 	struct bpf_link *link;
3333 
3334 	if (fd_empty(f))
3335 		return ERR_PTR(-EBADF);
3336 	if (fd_file(f)->f_op != &bpf_link_fops && fd_file(f)->f_op != &bpf_link_fops_poll)
3337 		return ERR_PTR(-EINVAL);
3338 
3339 	link = fd_file(f)->private_data;
3340 	bpf_link_inc(link);
3341 	return link;
3342 }
3343 EXPORT_SYMBOL(bpf_link_get_from_fd);
3344 
3345 static void bpf_tracing_link_release(struct bpf_link *link)
3346 {
3347 	struct bpf_tracing_link *tr_link =
3348 		container_of(link, struct bpf_tracing_link, link.link);
3349 
3350 	WARN_ON_ONCE(bpf_trampoline_unlink_prog(&tr_link->link,
3351 						tr_link->trampoline,
3352 						tr_link->tgt_prog));
3353 
3354 	bpf_trampoline_put(tr_link->trampoline);
3355 
3356 	/* tgt_prog is NULL if target is a kernel function */
3357 	if (tr_link->tgt_prog)
3358 		bpf_prog_put(tr_link->tgt_prog);
3359 }
3360 
3361 static void bpf_tracing_link_dealloc(struct bpf_link *link)
3362 {
3363 	struct bpf_tracing_link *tr_link =
3364 		container_of(link, struct bpf_tracing_link, link.link);
3365 
3366 	kfree(tr_link);
3367 }
3368 
3369 static void bpf_tracing_link_show_fdinfo(const struct bpf_link *link,
3370 					 struct seq_file *seq)
3371 {
3372 	struct bpf_tracing_link *tr_link =
3373 		container_of(link, struct bpf_tracing_link, link.link);
3374 	u32 target_btf_id, target_obj_id;
3375 
3376 	bpf_trampoline_unpack_key(tr_link->trampoline->key,
3377 				  &target_obj_id, &target_btf_id);
3378 	seq_printf(seq,
3379 		   "attach_type:\t%d\n"
3380 		   "target_obj_id:\t%u\n"
3381 		   "target_btf_id:\t%u\n",
3382 		   tr_link->attach_type,
3383 		   target_obj_id,
3384 		   target_btf_id);
3385 }
3386 
3387 static int bpf_tracing_link_fill_link_info(const struct bpf_link *link,
3388 					   struct bpf_link_info *info)
3389 {
3390 	struct bpf_tracing_link *tr_link =
3391 		container_of(link, struct bpf_tracing_link, link.link);
3392 
3393 	info->tracing.attach_type = tr_link->attach_type;
3394 	bpf_trampoline_unpack_key(tr_link->trampoline->key,
3395 				  &info->tracing.target_obj_id,
3396 				  &info->tracing.target_btf_id);
3397 
3398 	return 0;
3399 }
3400 
3401 static const struct bpf_link_ops bpf_tracing_link_lops = {
3402 	.release = bpf_tracing_link_release,
3403 	.dealloc = bpf_tracing_link_dealloc,
3404 	.show_fdinfo = bpf_tracing_link_show_fdinfo,
3405 	.fill_link_info = bpf_tracing_link_fill_link_info,
3406 };
3407 
3408 static int bpf_tracing_prog_attach(struct bpf_prog *prog,
3409 				   int tgt_prog_fd,
3410 				   u32 btf_id,
3411 				   u64 bpf_cookie)
3412 {
3413 	struct bpf_link_primer link_primer;
3414 	struct bpf_prog *tgt_prog = NULL;
3415 	struct bpf_trampoline *tr = NULL;
3416 	struct bpf_tracing_link *link;
3417 	u64 key = 0;
3418 	int err;
3419 
3420 	switch (prog->type) {
3421 	case BPF_PROG_TYPE_TRACING:
3422 		if (prog->expected_attach_type != BPF_TRACE_FENTRY &&
3423 		    prog->expected_attach_type != BPF_TRACE_FEXIT &&
3424 		    prog->expected_attach_type != BPF_MODIFY_RETURN) {
3425 			err = -EINVAL;
3426 			goto out_put_prog;
3427 		}
3428 		break;
3429 	case BPF_PROG_TYPE_EXT:
3430 		if (prog->expected_attach_type != 0) {
3431 			err = -EINVAL;
3432 			goto out_put_prog;
3433 		}
3434 		break;
3435 	case BPF_PROG_TYPE_LSM:
3436 		if (prog->expected_attach_type != BPF_LSM_MAC) {
3437 			err = -EINVAL;
3438 			goto out_put_prog;
3439 		}
3440 		break;
3441 	default:
3442 		err = -EINVAL;
3443 		goto out_put_prog;
3444 	}
3445 
3446 	if (!!tgt_prog_fd != !!btf_id) {
3447 		err = -EINVAL;
3448 		goto out_put_prog;
3449 	}
3450 
3451 	if (tgt_prog_fd) {
3452 		/*
3453 		 * For now we only allow new targets for BPF_PROG_TYPE_EXT. If this
3454 		 * part would be changed to implement the same for
3455 		 * BPF_PROG_TYPE_TRACING, do not forget to update the way how
3456 		 * attach_tracing_prog flag is set.
3457 		 */
3458 		if (prog->type != BPF_PROG_TYPE_EXT) {
3459 			err = -EINVAL;
3460 			goto out_put_prog;
3461 		}
3462 
3463 		tgt_prog = bpf_prog_get(tgt_prog_fd);
3464 		if (IS_ERR(tgt_prog)) {
3465 			err = PTR_ERR(tgt_prog);
3466 			tgt_prog = NULL;
3467 			goto out_put_prog;
3468 		}
3469 
3470 		key = bpf_trampoline_compute_key(tgt_prog, NULL, btf_id);
3471 	}
3472 
3473 	link = kzalloc(sizeof(*link), GFP_USER);
3474 	if (!link) {
3475 		err = -ENOMEM;
3476 		goto out_put_prog;
3477 	}
3478 	bpf_link_init(&link->link.link, BPF_LINK_TYPE_TRACING,
3479 		      &bpf_tracing_link_lops, prog);
3480 	link->attach_type = prog->expected_attach_type;
3481 	link->link.cookie = bpf_cookie;
3482 
3483 	mutex_lock(&prog->aux->dst_mutex);
3484 
3485 	/* There are a few possible cases here:
3486 	 *
3487 	 * - if prog->aux->dst_trampoline is set, the program was just loaded
3488 	 *   and not yet attached to anything, so we can use the values stored
3489 	 *   in prog->aux
3490 	 *
3491 	 * - if prog->aux->dst_trampoline is NULL, the program has already been
3492 	 *   attached to a target and its initial target was cleared (below)
3493 	 *
3494 	 * - if tgt_prog != NULL, the caller specified tgt_prog_fd +
3495 	 *   target_btf_id using the link_create API.
3496 	 *
3497 	 * - if tgt_prog == NULL when this function was called using the old
3498 	 *   raw_tracepoint_open API, and we need a target from prog->aux
3499 	 *
3500 	 * - if prog->aux->dst_trampoline and tgt_prog is NULL, the program
3501 	 *   was detached and is going for re-attachment.
3502 	 *
3503 	 * - if prog->aux->dst_trampoline is NULL and tgt_prog and prog->aux->attach_btf
3504 	 *   are NULL, then program was already attached and user did not provide
3505 	 *   tgt_prog_fd so we have no way to find out or create trampoline
3506 	 */
3507 	if (!prog->aux->dst_trampoline && !tgt_prog) {
3508 		/*
3509 		 * Allow re-attach for TRACING and LSM programs. If it's
3510 		 * currently linked, bpf_trampoline_link_prog will fail.
3511 		 * EXT programs need to specify tgt_prog_fd, so they
3512 		 * re-attach in separate code path.
3513 		 */
3514 		if (prog->type != BPF_PROG_TYPE_TRACING &&
3515 		    prog->type != BPF_PROG_TYPE_LSM) {
3516 			err = -EINVAL;
3517 			goto out_unlock;
3518 		}
3519 		/* We can allow re-attach only if we have valid attach_btf. */
3520 		if (!prog->aux->attach_btf) {
3521 			err = -EINVAL;
3522 			goto out_unlock;
3523 		}
3524 		btf_id = prog->aux->attach_btf_id;
3525 		key = bpf_trampoline_compute_key(NULL, prog->aux->attach_btf, btf_id);
3526 	}
3527 
3528 	if (!prog->aux->dst_trampoline ||
3529 	    (key && key != prog->aux->dst_trampoline->key)) {
3530 		/* If there is no saved target, or the specified target is
3531 		 * different from the destination specified at load time, we
3532 		 * need a new trampoline and a check for compatibility
3533 		 */
3534 		struct bpf_attach_target_info tgt_info = {};
3535 
3536 		err = bpf_check_attach_target(NULL, prog, tgt_prog, btf_id,
3537 					      &tgt_info);
3538 		if (err)
3539 			goto out_unlock;
3540 
3541 		if (tgt_info.tgt_mod) {
3542 			module_put(prog->aux->mod);
3543 			prog->aux->mod = tgt_info.tgt_mod;
3544 		}
3545 
3546 		tr = bpf_trampoline_get(key, &tgt_info);
3547 		if (!tr) {
3548 			err = -ENOMEM;
3549 			goto out_unlock;
3550 		}
3551 	} else {
3552 		/* The caller didn't specify a target, or the target was the
3553 		 * same as the destination supplied during program load. This
3554 		 * means we can reuse the trampoline and reference from program
3555 		 * load time, and there is no need to allocate a new one. This
3556 		 * can only happen once for any program, as the saved values in
3557 		 * prog->aux are cleared below.
3558 		 */
3559 		tr = prog->aux->dst_trampoline;
3560 		tgt_prog = prog->aux->dst_prog;
3561 	}
3562 
3563 	err = bpf_link_prime(&link->link.link, &link_primer);
3564 	if (err)
3565 		goto out_unlock;
3566 
3567 	err = bpf_trampoline_link_prog(&link->link, tr, tgt_prog);
3568 	if (err) {
3569 		bpf_link_cleanup(&link_primer);
3570 		link = NULL;
3571 		goto out_unlock;
3572 	}
3573 
3574 	link->tgt_prog = tgt_prog;
3575 	link->trampoline = tr;
3576 
3577 	/* Always clear the trampoline and target prog from prog->aux to make
3578 	 * sure the original attach destination is not kept alive after a
3579 	 * program is (re-)attached to another target.
3580 	 */
3581 	if (prog->aux->dst_prog &&
3582 	    (tgt_prog_fd || tr != prog->aux->dst_trampoline))
3583 		/* got extra prog ref from syscall, or attaching to different prog */
3584 		bpf_prog_put(prog->aux->dst_prog);
3585 	if (prog->aux->dst_trampoline && tr != prog->aux->dst_trampoline)
3586 		/* we allocated a new trampoline, so free the old one */
3587 		bpf_trampoline_put(prog->aux->dst_trampoline);
3588 
3589 	prog->aux->dst_prog = NULL;
3590 	prog->aux->dst_trampoline = NULL;
3591 	mutex_unlock(&prog->aux->dst_mutex);
3592 
3593 	return bpf_link_settle(&link_primer);
3594 out_unlock:
3595 	if (tr && tr != prog->aux->dst_trampoline)
3596 		bpf_trampoline_put(tr);
3597 	mutex_unlock(&prog->aux->dst_mutex);
3598 	kfree(link);
3599 out_put_prog:
3600 	if (tgt_prog_fd && tgt_prog)
3601 		bpf_prog_put(tgt_prog);
3602 	return err;
3603 }
3604 
3605 static void bpf_raw_tp_link_release(struct bpf_link *link)
3606 {
3607 	struct bpf_raw_tp_link *raw_tp =
3608 		container_of(link, struct bpf_raw_tp_link, link);
3609 
3610 	bpf_probe_unregister(raw_tp->btp, raw_tp);
3611 	bpf_put_raw_tracepoint(raw_tp->btp);
3612 }
3613 
3614 static void bpf_raw_tp_link_dealloc(struct bpf_link *link)
3615 {
3616 	struct bpf_raw_tp_link *raw_tp =
3617 		container_of(link, struct bpf_raw_tp_link, link);
3618 
3619 	kfree(raw_tp);
3620 }
3621 
3622 static void bpf_raw_tp_link_show_fdinfo(const struct bpf_link *link,
3623 					struct seq_file *seq)
3624 {
3625 	struct bpf_raw_tp_link *raw_tp_link =
3626 		container_of(link, struct bpf_raw_tp_link, link);
3627 
3628 	seq_printf(seq,
3629 		   "tp_name:\t%s\n",
3630 		   raw_tp_link->btp->tp->name);
3631 }
3632 
3633 static int bpf_copy_to_user(char __user *ubuf, const char *buf, u32 ulen,
3634 			    u32 len)
3635 {
3636 	if (ulen >= len + 1) {
3637 		if (copy_to_user(ubuf, buf, len + 1))
3638 			return -EFAULT;
3639 	} else {
3640 		char zero = '\0';
3641 
3642 		if (copy_to_user(ubuf, buf, ulen - 1))
3643 			return -EFAULT;
3644 		if (put_user(zero, ubuf + ulen - 1))
3645 			return -EFAULT;
3646 		return -ENOSPC;
3647 	}
3648 
3649 	return 0;
3650 }
3651 
3652 static int bpf_raw_tp_link_fill_link_info(const struct bpf_link *link,
3653 					  struct bpf_link_info *info)
3654 {
3655 	struct bpf_raw_tp_link *raw_tp_link =
3656 		container_of(link, struct bpf_raw_tp_link, link);
3657 	char __user *ubuf = u64_to_user_ptr(info->raw_tracepoint.tp_name);
3658 	const char *tp_name = raw_tp_link->btp->tp->name;
3659 	u32 ulen = info->raw_tracepoint.tp_name_len;
3660 	size_t tp_len = strlen(tp_name);
3661 
3662 	if (!ulen ^ !ubuf)
3663 		return -EINVAL;
3664 
3665 	info->raw_tracepoint.tp_name_len = tp_len + 1;
3666 
3667 	if (!ubuf)
3668 		return 0;
3669 
3670 	return bpf_copy_to_user(ubuf, tp_name, ulen, tp_len);
3671 }
3672 
3673 static const struct bpf_link_ops bpf_raw_tp_link_lops = {
3674 	.release = bpf_raw_tp_link_release,
3675 	.dealloc_deferred = bpf_raw_tp_link_dealloc,
3676 	.show_fdinfo = bpf_raw_tp_link_show_fdinfo,
3677 	.fill_link_info = bpf_raw_tp_link_fill_link_info,
3678 };
3679 
3680 #ifdef CONFIG_PERF_EVENTS
3681 struct bpf_perf_link {
3682 	struct bpf_link link;
3683 	struct file *perf_file;
3684 };
3685 
3686 static void bpf_perf_link_release(struct bpf_link *link)
3687 {
3688 	struct bpf_perf_link *perf_link = container_of(link, struct bpf_perf_link, link);
3689 	struct perf_event *event = perf_link->perf_file->private_data;
3690 
3691 	perf_event_free_bpf_prog(event);
3692 	fput(perf_link->perf_file);
3693 }
3694 
3695 static void bpf_perf_link_dealloc(struct bpf_link *link)
3696 {
3697 	struct bpf_perf_link *perf_link = container_of(link, struct bpf_perf_link, link);
3698 
3699 	kfree(perf_link);
3700 }
3701 
3702 static int bpf_perf_link_fill_common(const struct perf_event *event,
3703 				     char __user *uname, u32 *ulenp,
3704 				     u64 *probe_offset, u64 *probe_addr,
3705 				     u32 *fd_type, unsigned long *missed)
3706 {
3707 	const char *buf;
3708 	u32 prog_id, ulen;
3709 	size_t len;
3710 	int err;
3711 
3712 	ulen = *ulenp;
3713 	if (!ulen ^ !uname)
3714 		return -EINVAL;
3715 
3716 	err = bpf_get_perf_event_info(event, &prog_id, fd_type, &buf,
3717 				      probe_offset, probe_addr, missed);
3718 	if (err)
3719 		return err;
3720 
3721 	if (buf) {
3722 		len = strlen(buf);
3723 		*ulenp = len + 1;
3724 	} else {
3725 		*ulenp = 1;
3726 	}
3727 	if (!uname)
3728 		return 0;
3729 
3730 	if (buf) {
3731 		err = bpf_copy_to_user(uname, buf, ulen, len);
3732 		if (err)
3733 			return err;
3734 	} else {
3735 		char zero = '\0';
3736 
3737 		if (put_user(zero, uname))
3738 			return -EFAULT;
3739 	}
3740 	return 0;
3741 }
3742 
3743 #ifdef CONFIG_KPROBE_EVENTS
3744 static int bpf_perf_link_fill_kprobe(const struct perf_event *event,
3745 				     struct bpf_link_info *info)
3746 {
3747 	unsigned long missed;
3748 	char __user *uname;
3749 	u64 addr, offset;
3750 	u32 ulen, type;
3751 	int err;
3752 
3753 	uname = u64_to_user_ptr(info->perf_event.kprobe.func_name);
3754 	ulen = info->perf_event.kprobe.name_len;
3755 	err = bpf_perf_link_fill_common(event, uname, &ulen, &offset, &addr,
3756 					&type, &missed);
3757 	if (err)
3758 		return err;
3759 	if (type == BPF_FD_TYPE_KRETPROBE)
3760 		info->perf_event.type = BPF_PERF_EVENT_KRETPROBE;
3761 	else
3762 		info->perf_event.type = BPF_PERF_EVENT_KPROBE;
3763 	info->perf_event.kprobe.name_len = ulen;
3764 	info->perf_event.kprobe.offset = offset;
3765 	info->perf_event.kprobe.missed = missed;
3766 	if (!kallsyms_show_value(current_cred()))
3767 		addr = 0;
3768 	info->perf_event.kprobe.addr = addr;
3769 	info->perf_event.kprobe.cookie = event->bpf_cookie;
3770 	return 0;
3771 }
3772 #endif
3773 
3774 #ifdef CONFIG_UPROBE_EVENTS
3775 static int bpf_perf_link_fill_uprobe(const struct perf_event *event,
3776 				     struct bpf_link_info *info)
3777 {
3778 	char __user *uname;
3779 	u64 addr, offset;
3780 	u32 ulen, type;
3781 	int err;
3782 
3783 	uname = u64_to_user_ptr(info->perf_event.uprobe.file_name);
3784 	ulen = info->perf_event.uprobe.name_len;
3785 	err = bpf_perf_link_fill_common(event, uname, &ulen, &offset, &addr,
3786 					&type, NULL);
3787 	if (err)
3788 		return err;
3789 
3790 	if (type == BPF_FD_TYPE_URETPROBE)
3791 		info->perf_event.type = BPF_PERF_EVENT_URETPROBE;
3792 	else
3793 		info->perf_event.type = BPF_PERF_EVENT_UPROBE;
3794 	info->perf_event.uprobe.name_len = ulen;
3795 	info->perf_event.uprobe.offset = offset;
3796 	info->perf_event.uprobe.cookie = event->bpf_cookie;
3797 	return 0;
3798 }
3799 #endif
3800 
3801 static int bpf_perf_link_fill_probe(const struct perf_event *event,
3802 				    struct bpf_link_info *info)
3803 {
3804 #ifdef CONFIG_KPROBE_EVENTS
3805 	if (event->tp_event->flags & TRACE_EVENT_FL_KPROBE)
3806 		return bpf_perf_link_fill_kprobe(event, info);
3807 #endif
3808 #ifdef CONFIG_UPROBE_EVENTS
3809 	if (event->tp_event->flags & TRACE_EVENT_FL_UPROBE)
3810 		return bpf_perf_link_fill_uprobe(event, info);
3811 #endif
3812 	return -EOPNOTSUPP;
3813 }
3814 
3815 static int bpf_perf_link_fill_tracepoint(const struct perf_event *event,
3816 					 struct bpf_link_info *info)
3817 {
3818 	char __user *uname;
3819 	u32 ulen;
3820 	int err;
3821 
3822 	uname = u64_to_user_ptr(info->perf_event.tracepoint.tp_name);
3823 	ulen = info->perf_event.tracepoint.name_len;
3824 	err = bpf_perf_link_fill_common(event, uname, &ulen, NULL, NULL, NULL, NULL);
3825 	if (err)
3826 		return err;
3827 
3828 	info->perf_event.type = BPF_PERF_EVENT_TRACEPOINT;
3829 	info->perf_event.tracepoint.name_len = ulen;
3830 	info->perf_event.tracepoint.cookie = event->bpf_cookie;
3831 	return 0;
3832 }
3833 
3834 static int bpf_perf_link_fill_perf_event(const struct perf_event *event,
3835 					 struct bpf_link_info *info)
3836 {
3837 	info->perf_event.event.type = event->attr.type;
3838 	info->perf_event.event.config = event->attr.config;
3839 	info->perf_event.event.cookie = event->bpf_cookie;
3840 	info->perf_event.type = BPF_PERF_EVENT_EVENT;
3841 	return 0;
3842 }
3843 
3844 static int bpf_perf_link_fill_link_info(const struct bpf_link *link,
3845 					struct bpf_link_info *info)
3846 {
3847 	struct bpf_perf_link *perf_link;
3848 	const struct perf_event *event;
3849 
3850 	perf_link = container_of(link, struct bpf_perf_link, link);
3851 	event = perf_get_event(perf_link->perf_file);
3852 	if (IS_ERR(event))
3853 		return PTR_ERR(event);
3854 
3855 	switch (event->prog->type) {
3856 	case BPF_PROG_TYPE_PERF_EVENT:
3857 		return bpf_perf_link_fill_perf_event(event, info);
3858 	case BPF_PROG_TYPE_TRACEPOINT:
3859 		return bpf_perf_link_fill_tracepoint(event, info);
3860 	case BPF_PROG_TYPE_KPROBE:
3861 		return bpf_perf_link_fill_probe(event, info);
3862 	default:
3863 		return -EOPNOTSUPP;
3864 	}
3865 }
3866 
3867 static const struct bpf_link_ops bpf_perf_link_lops = {
3868 	.release = bpf_perf_link_release,
3869 	.dealloc = bpf_perf_link_dealloc,
3870 	.fill_link_info = bpf_perf_link_fill_link_info,
3871 };
3872 
3873 static int bpf_perf_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
3874 {
3875 	struct bpf_link_primer link_primer;
3876 	struct bpf_perf_link *link;
3877 	struct perf_event *event;
3878 	struct file *perf_file;
3879 	int err;
3880 
3881 	if (attr->link_create.flags)
3882 		return -EINVAL;
3883 
3884 	perf_file = perf_event_get(attr->link_create.target_fd);
3885 	if (IS_ERR(perf_file))
3886 		return PTR_ERR(perf_file);
3887 
3888 	link = kzalloc(sizeof(*link), GFP_USER);
3889 	if (!link) {
3890 		err = -ENOMEM;
3891 		goto out_put_file;
3892 	}
3893 	bpf_link_init(&link->link, BPF_LINK_TYPE_PERF_EVENT, &bpf_perf_link_lops, prog);
3894 	link->perf_file = perf_file;
3895 
3896 	err = bpf_link_prime(&link->link, &link_primer);
3897 	if (err) {
3898 		kfree(link);
3899 		goto out_put_file;
3900 	}
3901 
3902 	event = perf_file->private_data;
3903 	err = perf_event_set_bpf_prog(event, prog, attr->link_create.perf_event.bpf_cookie);
3904 	if (err) {
3905 		bpf_link_cleanup(&link_primer);
3906 		goto out_put_file;
3907 	}
3908 	/* perf_event_set_bpf_prog() doesn't take its own refcnt on prog */
3909 	bpf_prog_inc(prog);
3910 
3911 	return bpf_link_settle(&link_primer);
3912 
3913 out_put_file:
3914 	fput(perf_file);
3915 	return err;
3916 }
3917 #else
3918 static int bpf_perf_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
3919 {
3920 	return -EOPNOTSUPP;
3921 }
3922 #endif /* CONFIG_PERF_EVENTS */
3923 
3924 static int bpf_raw_tp_link_attach(struct bpf_prog *prog,
3925 				  const char __user *user_tp_name, u64 cookie)
3926 {
3927 	struct bpf_link_primer link_primer;
3928 	struct bpf_raw_tp_link *link;
3929 	struct bpf_raw_event_map *btp;
3930 	const char *tp_name;
3931 	char buf[128];
3932 	int err;
3933 
3934 	switch (prog->type) {
3935 	case BPF_PROG_TYPE_TRACING:
3936 	case BPF_PROG_TYPE_EXT:
3937 	case BPF_PROG_TYPE_LSM:
3938 		if (user_tp_name)
3939 			/* The attach point for this category of programs
3940 			 * should be specified via btf_id during program load.
3941 			 */
3942 			return -EINVAL;
3943 		if (prog->type == BPF_PROG_TYPE_TRACING &&
3944 		    prog->expected_attach_type == BPF_TRACE_RAW_TP) {
3945 			tp_name = prog->aux->attach_func_name;
3946 			break;
3947 		}
3948 		return bpf_tracing_prog_attach(prog, 0, 0, 0);
3949 	case BPF_PROG_TYPE_RAW_TRACEPOINT:
3950 	case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE:
3951 		if (strncpy_from_user(buf, user_tp_name, sizeof(buf) - 1) < 0)
3952 			return -EFAULT;
3953 		buf[sizeof(buf) - 1] = 0;
3954 		tp_name = buf;
3955 		break;
3956 	default:
3957 		return -EINVAL;
3958 	}
3959 
3960 	btp = bpf_get_raw_tracepoint(tp_name);
3961 	if (!btp)
3962 		return -ENOENT;
3963 
3964 	link = kzalloc(sizeof(*link), GFP_USER);
3965 	if (!link) {
3966 		err = -ENOMEM;
3967 		goto out_put_btp;
3968 	}
3969 	bpf_link_init_sleepable(&link->link, BPF_LINK_TYPE_RAW_TRACEPOINT,
3970 				&bpf_raw_tp_link_lops, prog,
3971 				tracepoint_is_faultable(btp->tp));
3972 	link->btp = btp;
3973 	link->cookie = cookie;
3974 
3975 	err = bpf_link_prime(&link->link, &link_primer);
3976 	if (err) {
3977 		kfree(link);
3978 		goto out_put_btp;
3979 	}
3980 
3981 	err = bpf_probe_register(link->btp, link);
3982 	if (err) {
3983 		bpf_link_cleanup(&link_primer);
3984 		goto out_put_btp;
3985 	}
3986 
3987 	return bpf_link_settle(&link_primer);
3988 
3989 out_put_btp:
3990 	bpf_put_raw_tracepoint(btp);
3991 	return err;
3992 }
3993 
3994 #define BPF_RAW_TRACEPOINT_OPEN_LAST_FIELD raw_tracepoint.cookie
3995 
3996 static int bpf_raw_tracepoint_open(const union bpf_attr *attr)
3997 {
3998 	struct bpf_prog *prog;
3999 	void __user *tp_name;
4000 	__u64 cookie;
4001 	int fd;
4002 
4003 	if (CHECK_ATTR(BPF_RAW_TRACEPOINT_OPEN))
4004 		return -EINVAL;
4005 
4006 	prog = bpf_prog_get(attr->raw_tracepoint.prog_fd);
4007 	if (IS_ERR(prog))
4008 		return PTR_ERR(prog);
4009 
4010 	tp_name = u64_to_user_ptr(attr->raw_tracepoint.name);
4011 	cookie = attr->raw_tracepoint.cookie;
4012 	fd = bpf_raw_tp_link_attach(prog, tp_name, cookie);
4013 	if (fd < 0)
4014 		bpf_prog_put(prog);
4015 	return fd;
4016 }
4017 
4018 static enum bpf_prog_type
4019 attach_type_to_prog_type(enum bpf_attach_type attach_type)
4020 {
4021 	switch (attach_type) {
4022 	case BPF_CGROUP_INET_INGRESS:
4023 	case BPF_CGROUP_INET_EGRESS:
4024 		return BPF_PROG_TYPE_CGROUP_SKB;
4025 	case BPF_CGROUP_INET_SOCK_CREATE:
4026 	case BPF_CGROUP_INET_SOCK_RELEASE:
4027 	case BPF_CGROUP_INET4_POST_BIND:
4028 	case BPF_CGROUP_INET6_POST_BIND:
4029 		return BPF_PROG_TYPE_CGROUP_SOCK;
4030 	case BPF_CGROUP_INET4_BIND:
4031 	case BPF_CGROUP_INET6_BIND:
4032 	case BPF_CGROUP_INET4_CONNECT:
4033 	case BPF_CGROUP_INET6_CONNECT:
4034 	case BPF_CGROUP_UNIX_CONNECT:
4035 	case BPF_CGROUP_INET4_GETPEERNAME:
4036 	case BPF_CGROUP_INET6_GETPEERNAME:
4037 	case BPF_CGROUP_UNIX_GETPEERNAME:
4038 	case BPF_CGROUP_INET4_GETSOCKNAME:
4039 	case BPF_CGROUP_INET6_GETSOCKNAME:
4040 	case BPF_CGROUP_UNIX_GETSOCKNAME:
4041 	case BPF_CGROUP_UDP4_SENDMSG:
4042 	case BPF_CGROUP_UDP6_SENDMSG:
4043 	case BPF_CGROUP_UNIX_SENDMSG:
4044 	case BPF_CGROUP_UDP4_RECVMSG:
4045 	case BPF_CGROUP_UDP6_RECVMSG:
4046 	case BPF_CGROUP_UNIX_RECVMSG:
4047 		return BPF_PROG_TYPE_CGROUP_SOCK_ADDR;
4048 	case BPF_CGROUP_SOCK_OPS:
4049 		return BPF_PROG_TYPE_SOCK_OPS;
4050 	case BPF_CGROUP_DEVICE:
4051 		return BPF_PROG_TYPE_CGROUP_DEVICE;
4052 	case BPF_SK_MSG_VERDICT:
4053 		return BPF_PROG_TYPE_SK_MSG;
4054 	case BPF_SK_SKB_STREAM_PARSER:
4055 	case BPF_SK_SKB_STREAM_VERDICT:
4056 	case BPF_SK_SKB_VERDICT:
4057 		return BPF_PROG_TYPE_SK_SKB;
4058 	case BPF_LIRC_MODE2:
4059 		return BPF_PROG_TYPE_LIRC_MODE2;
4060 	case BPF_FLOW_DISSECTOR:
4061 		return BPF_PROG_TYPE_FLOW_DISSECTOR;
4062 	case BPF_CGROUP_SYSCTL:
4063 		return BPF_PROG_TYPE_CGROUP_SYSCTL;
4064 	case BPF_CGROUP_GETSOCKOPT:
4065 	case BPF_CGROUP_SETSOCKOPT:
4066 		return BPF_PROG_TYPE_CGROUP_SOCKOPT;
4067 	case BPF_TRACE_ITER:
4068 	case BPF_TRACE_RAW_TP:
4069 	case BPF_TRACE_FENTRY:
4070 	case BPF_TRACE_FEXIT:
4071 	case BPF_MODIFY_RETURN:
4072 		return BPF_PROG_TYPE_TRACING;
4073 	case BPF_LSM_MAC:
4074 		return BPF_PROG_TYPE_LSM;
4075 	case BPF_SK_LOOKUP:
4076 		return BPF_PROG_TYPE_SK_LOOKUP;
4077 	case BPF_XDP:
4078 		return BPF_PROG_TYPE_XDP;
4079 	case BPF_LSM_CGROUP:
4080 		return BPF_PROG_TYPE_LSM;
4081 	case BPF_TCX_INGRESS:
4082 	case BPF_TCX_EGRESS:
4083 	case BPF_NETKIT_PRIMARY:
4084 	case BPF_NETKIT_PEER:
4085 		return BPF_PROG_TYPE_SCHED_CLS;
4086 	default:
4087 		return BPF_PROG_TYPE_UNSPEC;
4088 	}
4089 }
4090 
4091 static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog,
4092 					     enum bpf_attach_type attach_type)
4093 {
4094 	enum bpf_prog_type ptype;
4095 
4096 	switch (prog->type) {
4097 	case BPF_PROG_TYPE_CGROUP_SOCK:
4098 	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
4099 	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
4100 	case BPF_PROG_TYPE_SK_LOOKUP:
4101 		return attach_type == prog->expected_attach_type ? 0 : -EINVAL;
4102 	case BPF_PROG_TYPE_CGROUP_SKB:
4103 		if (!bpf_token_capable(prog->aux->token, CAP_NET_ADMIN))
4104 			/* cg-skb progs can be loaded by unpriv user.
4105 			 * check permissions at attach time.
4106 			 */
4107 			return -EPERM;
4108 
4109 		ptype = attach_type_to_prog_type(attach_type);
4110 		if (prog->type != ptype)
4111 			return -EINVAL;
4112 
4113 		return prog->enforce_expected_attach_type &&
4114 			prog->expected_attach_type != attach_type ?
4115 			-EINVAL : 0;
4116 	case BPF_PROG_TYPE_EXT:
4117 		return 0;
4118 	case BPF_PROG_TYPE_NETFILTER:
4119 		if (attach_type != BPF_NETFILTER)
4120 			return -EINVAL;
4121 		return 0;
4122 	case BPF_PROG_TYPE_PERF_EVENT:
4123 	case BPF_PROG_TYPE_TRACEPOINT:
4124 		if (attach_type != BPF_PERF_EVENT)
4125 			return -EINVAL;
4126 		return 0;
4127 	case BPF_PROG_TYPE_KPROBE:
4128 		if (prog->expected_attach_type == BPF_TRACE_KPROBE_MULTI &&
4129 		    attach_type != BPF_TRACE_KPROBE_MULTI)
4130 			return -EINVAL;
4131 		if (prog->expected_attach_type == BPF_TRACE_KPROBE_SESSION &&
4132 		    attach_type != BPF_TRACE_KPROBE_SESSION)
4133 			return -EINVAL;
4134 		if (prog->expected_attach_type == BPF_TRACE_UPROBE_MULTI &&
4135 		    attach_type != BPF_TRACE_UPROBE_MULTI)
4136 			return -EINVAL;
4137 		if (prog->expected_attach_type == BPF_TRACE_UPROBE_SESSION &&
4138 		    attach_type != BPF_TRACE_UPROBE_SESSION)
4139 			return -EINVAL;
4140 		if (attach_type != BPF_PERF_EVENT &&
4141 		    attach_type != BPF_TRACE_KPROBE_MULTI &&
4142 		    attach_type != BPF_TRACE_KPROBE_SESSION &&
4143 		    attach_type != BPF_TRACE_UPROBE_MULTI &&
4144 		    attach_type != BPF_TRACE_UPROBE_SESSION)
4145 			return -EINVAL;
4146 		return 0;
4147 	case BPF_PROG_TYPE_SCHED_CLS:
4148 		if (attach_type != BPF_TCX_INGRESS &&
4149 		    attach_type != BPF_TCX_EGRESS &&
4150 		    attach_type != BPF_NETKIT_PRIMARY &&
4151 		    attach_type != BPF_NETKIT_PEER)
4152 			return -EINVAL;
4153 		return 0;
4154 	default:
4155 		ptype = attach_type_to_prog_type(attach_type);
4156 		if (ptype == BPF_PROG_TYPE_UNSPEC || ptype != prog->type)
4157 			return -EINVAL;
4158 		return 0;
4159 	}
4160 }
4161 
4162 #define BPF_PROG_ATTACH_LAST_FIELD expected_revision
4163 
4164 #define BPF_F_ATTACH_MASK_BASE	\
4165 	(BPF_F_ALLOW_OVERRIDE |	\
4166 	 BPF_F_ALLOW_MULTI |	\
4167 	 BPF_F_REPLACE)
4168 
4169 #define BPF_F_ATTACH_MASK_MPROG	\
4170 	(BPF_F_REPLACE |	\
4171 	 BPF_F_BEFORE |		\
4172 	 BPF_F_AFTER |		\
4173 	 BPF_F_ID |		\
4174 	 BPF_F_LINK)
4175 
4176 static int bpf_prog_attach(const union bpf_attr *attr)
4177 {
4178 	enum bpf_prog_type ptype;
4179 	struct bpf_prog *prog;
4180 	int ret;
4181 
4182 	if (CHECK_ATTR(BPF_PROG_ATTACH))
4183 		return -EINVAL;
4184 
4185 	ptype = attach_type_to_prog_type(attr->attach_type);
4186 	if (ptype == BPF_PROG_TYPE_UNSPEC)
4187 		return -EINVAL;
4188 	if (bpf_mprog_supported(ptype)) {
4189 		if (attr->attach_flags & ~BPF_F_ATTACH_MASK_MPROG)
4190 			return -EINVAL;
4191 	} else {
4192 		if (attr->attach_flags & ~BPF_F_ATTACH_MASK_BASE)
4193 			return -EINVAL;
4194 		if (attr->relative_fd ||
4195 		    attr->expected_revision)
4196 			return -EINVAL;
4197 	}
4198 
4199 	prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype);
4200 	if (IS_ERR(prog))
4201 		return PTR_ERR(prog);
4202 
4203 	if (bpf_prog_attach_check_attach_type(prog, attr->attach_type)) {
4204 		bpf_prog_put(prog);
4205 		return -EINVAL;
4206 	}
4207 
4208 	switch (ptype) {
4209 	case BPF_PROG_TYPE_SK_SKB:
4210 	case BPF_PROG_TYPE_SK_MSG:
4211 		ret = sock_map_get_from_fd(attr, prog);
4212 		break;
4213 	case BPF_PROG_TYPE_LIRC_MODE2:
4214 		ret = lirc_prog_attach(attr, prog);
4215 		break;
4216 	case BPF_PROG_TYPE_FLOW_DISSECTOR:
4217 		ret = netns_bpf_prog_attach(attr, prog);
4218 		break;
4219 	case BPF_PROG_TYPE_CGROUP_DEVICE:
4220 	case BPF_PROG_TYPE_CGROUP_SKB:
4221 	case BPF_PROG_TYPE_CGROUP_SOCK:
4222 	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
4223 	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
4224 	case BPF_PROG_TYPE_CGROUP_SYSCTL:
4225 	case BPF_PROG_TYPE_SOCK_OPS:
4226 	case BPF_PROG_TYPE_LSM:
4227 		if (ptype == BPF_PROG_TYPE_LSM &&
4228 		    prog->expected_attach_type != BPF_LSM_CGROUP)
4229 			ret = -EINVAL;
4230 		else
4231 			ret = cgroup_bpf_prog_attach(attr, ptype, prog);
4232 		break;
4233 	case BPF_PROG_TYPE_SCHED_CLS:
4234 		if (attr->attach_type == BPF_TCX_INGRESS ||
4235 		    attr->attach_type == BPF_TCX_EGRESS)
4236 			ret = tcx_prog_attach(attr, prog);
4237 		else
4238 			ret = netkit_prog_attach(attr, prog);
4239 		break;
4240 	default:
4241 		ret = -EINVAL;
4242 	}
4243 
4244 	if (ret)
4245 		bpf_prog_put(prog);
4246 	return ret;
4247 }
4248 
4249 #define BPF_PROG_DETACH_LAST_FIELD expected_revision
4250 
4251 static int bpf_prog_detach(const union bpf_attr *attr)
4252 {
4253 	struct bpf_prog *prog = NULL;
4254 	enum bpf_prog_type ptype;
4255 	int ret;
4256 
4257 	if (CHECK_ATTR(BPF_PROG_DETACH))
4258 		return -EINVAL;
4259 
4260 	ptype = attach_type_to_prog_type(attr->attach_type);
4261 	if (bpf_mprog_supported(ptype)) {
4262 		if (ptype == BPF_PROG_TYPE_UNSPEC)
4263 			return -EINVAL;
4264 		if (attr->attach_flags & ~BPF_F_ATTACH_MASK_MPROG)
4265 			return -EINVAL;
4266 		if (attr->attach_bpf_fd) {
4267 			prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype);
4268 			if (IS_ERR(prog))
4269 				return PTR_ERR(prog);
4270 		}
4271 	} else if (attr->attach_flags ||
4272 		   attr->relative_fd ||
4273 		   attr->expected_revision) {
4274 		return -EINVAL;
4275 	}
4276 
4277 	switch (ptype) {
4278 	case BPF_PROG_TYPE_SK_MSG:
4279 	case BPF_PROG_TYPE_SK_SKB:
4280 		ret = sock_map_prog_detach(attr, ptype);
4281 		break;
4282 	case BPF_PROG_TYPE_LIRC_MODE2:
4283 		ret = lirc_prog_detach(attr);
4284 		break;
4285 	case BPF_PROG_TYPE_FLOW_DISSECTOR:
4286 		ret = netns_bpf_prog_detach(attr, ptype);
4287 		break;
4288 	case BPF_PROG_TYPE_CGROUP_DEVICE:
4289 	case BPF_PROG_TYPE_CGROUP_SKB:
4290 	case BPF_PROG_TYPE_CGROUP_SOCK:
4291 	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
4292 	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
4293 	case BPF_PROG_TYPE_CGROUP_SYSCTL:
4294 	case BPF_PROG_TYPE_SOCK_OPS:
4295 	case BPF_PROG_TYPE_LSM:
4296 		ret = cgroup_bpf_prog_detach(attr, ptype);
4297 		break;
4298 	case BPF_PROG_TYPE_SCHED_CLS:
4299 		if (attr->attach_type == BPF_TCX_INGRESS ||
4300 		    attr->attach_type == BPF_TCX_EGRESS)
4301 			ret = tcx_prog_detach(attr, prog);
4302 		else
4303 			ret = netkit_prog_detach(attr, prog);
4304 		break;
4305 	default:
4306 		ret = -EINVAL;
4307 	}
4308 
4309 	if (prog)
4310 		bpf_prog_put(prog);
4311 	return ret;
4312 }
4313 
4314 #define BPF_PROG_QUERY_LAST_FIELD query.revision
4315 
4316 static int bpf_prog_query(const union bpf_attr *attr,
4317 			  union bpf_attr __user *uattr)
4318 {
4319 	if (!bpf_net_capable())
4320 		return -EPERM;
4321 	if (CHECK_ATTR(BPF_PROG_QUERY))
4322 		return -EINVAL;
4323 	if (attr->query.query_flags & ~BPF_F_QUERY_EFFECTIVE)
4324 		return -EINVAL;
4325 
4326 	switch (attr->query.attach_type) {
4327 	case BPF_CGROUP_INET_INGRESS:
4328 	case BPF_CGROUP_INET_EGRESS:
4329 	case BPF_CGROUP_INET_SOCK_CREATE:
4330 	case BPF_CGROUP_INET_SOCK_RELEASE:
4331 	case BPF_CGROUP_INET4_BIND:
4332 	case BPF_CGROUP_INET6_BIND:
4333 	case BPF_CGROUP_INET4_POST_BIND:
4334 	case BPF_CGROUP_INET6_POST_BIND:
4335 	case BPF_CGROUP_INET4_CONNECT:
4336 	case BPF_CGROUP_INET6_CONNECT:
4337 	case BPF_CGROUP_UNIX_CONNECT:
4338 	case BPF_CGROUP_INET4_GETPEERNAME:
4339 	case BPF_CGROUP_INET6_GETPEERNAME:
4340 	case BPF_CGROUP_UNIX_GETPEERNAME:
4341 	case BPF_CGROUP_INET4_GETSOCKNAME:
4342 	case BPF_CGROUP_INET6_GETSOCKNAME:
4343 	case BPF_CGROUP_UNIX_GETSOCKNAME:
4344 	case BPF_CGROUP_UDP4_SENDMSG:
4345 	case BPF_CGROUP_UDP6_SENDMSG:
4346 	case BPF_CGROUP_UNIX_SENDMSG:
4347 	case BPF_CGROUP_UDP4_RECVMSG:
4348 	case BPF_CGROUP_UDP6_RECVMSG:
4349 	case BPF_CGROUP_UNIX_RECVMSG:
4350 	case BPF_CGROUP_SOCK_OPS:
4351 	case BPF_CGROUP_DEVICE:
4352 	case BPF_CGROUP_SYSCTL:
4353 	case BPF_CGROUP_GETSOCKOPT:
4354 	case BPF_CGROUP_SETSOCKOPT:
4355 	case BPF_LSM_CGROUP:
4356 		return cgroup_bpf_prog_query(attr, uattr);
4357 	case BPF_LIRC_MODE2:
4358 		return lirc_prog_query(attr, uattr);
4359 	case BPF_FLOW_DISSECTOR:
4360 	case BPF_SK_LOOKUP:
4361 		return netns_bpf_prog_query(attr, uattr);
4362 	case BPF_SK_SKB_STREAM_PARSER:
4363 	case BPF_SK_SKB_STREAM_VERDICT:
4364 	case BPF_SK_MSG_VERDICT:
4365 	case BPF_SK_SKB_VERDICT:
4366 		return sock_map_bpf_prog_query(attr, uattr);
4367 	case BPF_TCX_INGRESS:
4368 	case BPF_TCX_EGRESS:
4369 		return tcx_prog_query(attr, uattr);
4370 	case BPF_NETKIT_PRIMARY:
4371 	case BPF_NETKIT_PEER:
4372 		return netkit_prog_query(attr, uattr);
4373 	default:
4374 		return -EINVAL;
4375 	}
4376 }
4377 
4378 #define BPF_PROG_TEST_RUN_LAST_FIELD test.batch_size
4379 
4380 static int bpf_prog_test_run(const union bpf_attr *attr,
4381 			     union bpf_attr __user *uattr)
4382 {
4383 	struct bpf_prog *prog;
4384 	int ret = -ENOTSUPP;
4385 
4386 	if (CHECK_ATTR(BPF_PROG_TEST_RUN))
4387 		return -EINVAL;
4388 
4389 	if ((attr->test.ctx_size_in && !attr->test.ctx_in) ||
4390 	    (!attr->test.ctx_size_in && attr->test.ctx_in))
4391 		return -EINVAL;
4392 
4393 	if ((attr->test.ctx_size_out && !attr->test.ctx_out) ||
4394 	    (!attr->test.ctx_size_out && attr->test.ctx_out))
4395 		return -EINVAL;
4396 
4397 	prog = bpf_prog_get(attr->test.prog_fd);
4398 	if (IS_ERR(prog))
4399 		return PTR_ERR(prog);
4400 
4401 	if (prog->aux->ops->test_run)
4402 		ret = prog->aux->ops->test_run(prog, attr, uattr);
4403 
4404 	bpf_prog_put(prog);
4405 	return ret;
4406 }
4407 
4408 #define BPF_OBJ_GET_NEXT_ID_LAST_FIELD next_id
4409 
4410 static int bpf_obj_get_next_id(const union bpf_attr *attr,
4411 			       union bpf_attr __user *uattr,
4412 			       struct idr *idr,
4413 			       spinlock_t *lock)
4414 {
4415 	u32 next_id = attr->start_id;
4416 	int err = 0;
4417 
4418 	if (CHECK_ATTR(BPF_OBJ_GET_NEXT_ID) || next_id >= INT_MAX)
4419 		return -EINVAL;
4420 
4421 	if (!capable(CAP_SYS_ADMIN))
4422 		return -EPERM;
4423 
4424 	next_id++;
4425 	spin_lock_bh(lock);
4426 	if (!idr_get_next(idr, &next_id))
4427 		err = -ENOENT;
4428 	spin_unlock_bh(lock);
4429 
4430 	if (!err)
4431 		err = put_user(next_id, &uattr->next_id);
4432 
4433 	return err;
4434 }
4435 
4436 struct bpf_map *bpf_map_get_curr_or_next(u32 *id)
4437 {
4438 	struct bpf_map *map;
4439 
4440 	spin_lock_bh(&map_idr_lock);
4441 again:
4442 	map = idr_get_next(&map_idr, id);
4443 	if (map) {
4444 		map = __bpf_map_inc_not_zero(map, false);
4445 		if (IS_ERR(map)) {
4446 			(*id)++;
4447 			goto again;
4448 		}
4449 	}
4450 	spin_unlock_bh(&map_idr_lock);
4451 
4452 	return map;
4453 }
4454 
4455 struct bpf_prog *bpf_prog_get_curr_or_next(u32 *id)
4456 {
4457 	struct bpf_prog *prog;
4458 
4459 	spin_lock_bh(&prog_idr_lock);
4460 again:
4461 	prog = idr_get_next(&prog_idr, id);
4462 	if (prog) {
4463 		prog = bpf_prog_inc_not_zero(prog);
4464 		if (IS_ERR(prog)) {
4465 			(*id)++;
4466 			goto again;
4467 		}
4468 	}
4469 	spin_unlock_bh(&prog_idr_lock);
4470 
4471 	return prog;
4472 }
4473 
4474 #define BPF_PROG_GET_FD_BY_ID_LAST_FIELD prog_id
4475 
4476 struct bpf_prog *bpf_prog_by_id(u32 id)
4477 {
4478 	struct bpf_prog *prog;
4479 
4480 	if (!id)
4481 		return ERR_PTR(-ENOENT);
4482 
4483 	spin_lock_bh(&prog_idr_lock);
4484 	prog = idr_find(&prog_idr, id);
4485 	if (prog)
4486 		prog = bpf_prog_inc_not_zero(prog);
4487 	else
4488 		prog = ERR_PTR(-ENOENT);
4489 	spin_unlock_bh(&prog_idr_lock);
4490 	return prog;
4491 }
4492 
4493 static int bpf_prog_get_fd_by_id(const union bpf_attr *attr)
4494 {
4495 	struct bpf_prog *prog;
4496 	u32 id = attr->prog_id;
4497 	int fd;
4498 
4499 	if (CHECK_ATTR(BPF_PROG_GET_FD_BY_ID))
4500 		return -EINVAL;
4501 
4502 	if (!capable(CAP_SYS_ADMIN))
4503 		return -EPERM;
4504 
4505 	prog = bpf_prog_by_id(id);
4506 	if (IS_ERR(prog))
4507 		return PTR_ERR(prog);
4508 
4509 	fd = bpf_prog_new_fd(prog);
4510 	if (fd < 0)
4511 		bpf_prog_put(prog);
4512 
4513 	return fd;
4514 }
4515 
4516 #define BPF_MAP_GET_FD_BY_ID_LAST_FIELD open_flags
4517 
4518 static int bpf_map_get_fd_by_id(const union bpf_attr *attr)
4519 {
4520 	struct bpf_map *map;
4521 	u32 id = attr->map_id;
4522 	int f_flags;
4523 	int fd;
4524 
4525 	if (CHECK_ATTR(BPF_MAP_GET_FD_BY_ID) ||
4526 	    attr->open_flags & ~BPF_OBJ_FLAG_MASK)
4527 		return -EINVAL;
4528 
4529 	if (!capable(CAP_SYS_ADMIN))
4530 		return -EPERM;
4531 
4532 	f_flags = bpf_get_file_flag(attr->open_flags);
4533 	if (f_flags < 0)
4534 		return f_flags;
4535 
4536 	spin_lock_bh(&map_idr_lock);
4537 	map = idr_find(&map_idr, id);
4538 	if (map)
4539 		map = __bpf_map_inc_not_zero(map, true);
4540 	else
4541 		map = ERR_PTR(-ENOENT);
4542 	spin_unlock_bh(&map_idr_lock);
4543 
4544 	if (IS_ERR(map))
4545 		return PTR_ERR(map);
4546 
4547 	fd = bpf_map_new_fd(map, f_flags);
4548 	if (fd < 0)
4549 		bpf_map_put_with_uref(map);
4550 
4551 	return fd;
4552 }
4553 
4554 static const struct bpf_map *bpf_map_from_imm(const struct bpf_prog *prog,
4555 					      unsigned long addr, u32 *off,
4556 					      u32 *type)
4557 {
4558 	const struct bpf_map *map;
4559 	int i;
4560 
4561 	mutex_lock(&prog->aux->used_maps_mutex);
4562 	for (i = 0, *off = 0; i < prog->aux->used_map_cnt; i++) {
4563 		map = prog->aux->used_maps[i];
4564 		if (map == (void *)addr) {
4565 			*type = BPF_PSEUDO_MAP_FD;
4566 			goto out;
4567 		}
4568 		if (!map->ops->map_direct_value_meta)
4569 			continue;
4570 		if (!map->ops->map_direct_value_meta(map, addr, off)) {
4571 			*type = BPF_PSEUDO_MAP_VALUE;
4572 			goto out;
4573 		}
4574 	}
4575 	map = NULL;
4576 
4577 out:
4578 	mutex_unlock(&prog->aux->used_maps_mutex);
4579 	return map;
4580 }
4581 
4582 static struct bpf_insn *bpf_insn_prepare_dump(const struct bpf_prog *prog,
4583 					      const struct cred *f_cred)
4584 {
4585 	const struct bpf_map *map;
4586 	struct bpf_insn *insns;
4587 	u32 off, type;
4588 	u64 imm;
4589 	u8 code;
4590 	int i;
4591 
4592 	insns = kmemdup(prog->insnsi, bpf_prog_insn_size(prog),
4593 			GFP_USER);
4594 	if (!insns)
4595 		return insns;
4596 
4597 	for (i = 0; i < prog->len; i++) {
4598 		code = insns[i].code;
4599 
4600 		if (code == (BPF_JMP | BPF_TAIL_CALL)) {
4601 			insns[i].code = BPF_JMP | BPF_CALL;
4602 			insns[i].imm = BPF_FUNC_tail_call;
4603 			/* fall-through */
4604 		}
4605 		if (code == (BPF_JMP | BPF_CALL) ||
4606 		    code == (BPF_JMP | BPF_CALL_ARGS)) {
4607 			if (code == (BPF_JMP | BPF_CALL_ARGS))
4608 				insns[i].code = BPF_JMP | BPF_CALL;
4609 			if (!bpf_dump_raw_ok(f_cred))
4610 				insns[i].imm = 0;
4611 			continue;
4612 		}
4613 		if (BPF_CLASS(code) == BPF_LDX && BPF_MODE(code) == BPF_PROBE_MEM) {
4614 			insns[i].code = BPF_LDX | BPF_SIZE(code) | BPF_MEM;
4615 			continue;
4616 		}
4617 
4618 		if ((BPF_CLASS(code) == BPF_LDX || BPF_CLASS(code) == BPF_STX ||
4619 		     BPF_CLASS(code) == BPF_ST) && BPF_MODE(code) == BPF_PROBE_MEM32) {
4620 			insns[i].code = BPF_CLASS(code) | BPF_SIZE(code) | BPF_MEM;
4621 			continue;
4622 		}
4623 
4624 		if (code != (BPF_LD | BPF_IMM | BPF_DW))
4625 			continue;
4626 
4627 		imm = ((u64)insns[i + 1].imm << 32) | (u32)insns[i].imm;
4628 		map = bpf_map_from_imm(prog, imm, &off, &type);
4629 		if (map) {
4630 			insns[i].src_reg = type;
4631 			insns[i].imm = map->id;
4632 			insns[i + 1].imm = off;
4633 			continue;
4634 		}
4635 	}
4636 
4637 	return insns;
4638 }
4639 
4640 static int set_info_rec_size(struct bpf_prog_info *info)
4641 {
4642 	/*
4643 	 * Ensure info.*_rec_size is the same as kernel expected size
4644 	 *
4645 	 * or
4646 	 *
4647 	 * Only allow zero *_rec_size if both _rec_size and _cnt are
4648 	 * zero.  In this case, the kernel will set the expected
4649 	 * _rec_size back to the info.
4650 	 */
4651 
4652 	if ((info->nr_func_info || info->func_info_rec_size) &&
4653 	    info->func_info_rec_size != sizeof(struct bpf_func_info))
4654 		return -EINVAL;
4655 
4656 	if ((info->nr_line_info || info->line_info_rec_size) &&
4657 	    info->line_info_rec_size != sizeof(struct bpf_line_info))
4658 		return -EINVAL;
4659 
4660 	if ((info->nr_jited_line_info || info->jited_line_info_rec_size) &&
4661 	    info->jited_line_info_rec_size != sizeof(__u64))
4662 		return -EINVAL;
4663 
4664 	info->func_info_rec_size = sizeof(struct bpf_func_info);
4665 	info->line_info_rec_size = sizeof(struct bpf_line_info);
4666 	info->jited_line_info_rec_size = sizeof(__u64);
4667 
4668 	return 0;
4669 }
4670 
4671 static int bpf_prog_get_info_by_fd(struct file *file,
4672 				   struct bpf_prog *prog,
4673 				   const union bpf_attr *attr,
4674 				   union bpf_attr __user *uattr)
4675 {
4676 	struct bpf_prog_info __user *uinfo = u64_to_user_ptr(attr->info.info);
4677 	struct btf *attach_btf = bpf_prog_get_target_btf(prog);
4678 	struct bpf_prog_info info;
4679 	u32 info_len = attr->info.info_len;
4680 	struct bpf_prog_kstats stats;
4681 	char __user *uinsns;
4682 	u32 ulen;
4683 	int err;
4684 
4685 	err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len);
4686 	if (err)
4687 		return err;
4688 	info_len = min_t(u32, sizeof(info), info_len);
4689 
4690 	memset(&info, 0, sizeof(info));
4691 	if (copy_from_user(&info, uinfo, info_len))
4692 		return -EFAULT;
4693 
4694 	info.type = prog->type;
4695 	info.id = prog->aux->id;
4696 	info.load_time = prog->aux->load_time;
4697 	info.created_by_uid = from_kuid_munged(current_user_ns(),
4698 					       prog->aux->user->uid);
4699 	info.gpl_compatible = prog->gpl_compatible;
4700 
4701 	memcpy(info.tag, prog->tag, sizeof(prog->tag));
4702 	memcpy(info.name, prog->aux->name, sizeof(prog->aux->name));
4703 
4704 	mutex_lock(&prog->aux->used_maps_mutex);
4705 	ulen = info.nr_map_ids;
4706 	info.nr_map_ids = prog->aux->used_map_cnt;
4707 	ulen = min_t(u32, info.nr_map_ids, ulen);
4708 	if (ulen) {
4709 		u32 __user *user_map_ids = u64_to_user_ptr(info.map_ids);
4710 		u32 i;
4711 
4712 		for (i = 0; i < ulen; i++)
4713 			if (put_user(prog->aux->used_maps[i]->id,
4714 				     &user_map_ids[i])) {
4715 				mutex_unlock(&prog->aux->used_maps_mutex);
4716 				return -EFAULT;
4717 			}
4718 	}
4719 	mutex_unlock(&prog->aux->used_maps_mutex);
4720 
4721 	err = set_info_rec_size(&info);
4722 	if (err)
4723 		return err;
4724 
4725 	bpf_prog_get_stats(prog, &stats);
4726 	info.run_time_ns = stats.nsecs;
4727 	info.run_cnt = stats.cnt;
4728 	info.recursion_misses = stats.misses;
4729 
4730 	info.verified_insns = prog->aux->verified_insns;
4731 
4732 	if (!bpf_capable()) {
4733 		info.jited_prog_len = 0;
4734 		info.xlated_prog_len = 0;
4735 		info.nr_jited_ksyms = 0;
4736 		info.nr_jited_func_lens = 0;
4737 		info.nr_func_info = 0;
4738 		info.nr_line_info = 0;
4739 		info.nr_jited_line_info = 0;
4740 		goto done;
4741 	}
4742 
4743 	ulen = info.xlated_prog_len;
4744 	info.xlated_prog_len = bpf_prog_insn_size(prog);
4745 	if (info.xlated_prog_len && ulen) {
4746 		struct bpf_insn *insns_sanitized;
4747 		bool fault;
4748 
4749 		if (prog->blinded && !bpf_dump_raw_ok(file->f_cred)) {
4750 			info.xlated_prog_insns = 0;
4751 			goto done;
4752 		}
4753 		insns_sanitized = bpf_insn_prepare_dump(prog, file->f_cred);
4754 		if (!insns_sanitized)
4755 			return -ENOMEM;
4756 		uinsns = u64_to_user_ptr(info.xlated_prog_insns);
4757 		ulen = min_t(u32, info.xlated_prog_len, ulen);
4758 		fault = copy_to_user(uinsns, insns_sanitized, ulen);
4759 		kfree(insns_sanitized);
4760 		if (fault)
4761 			return -EFAULT;
4762 	}
4763 
4764 	if (bpf_prog_is_offloaded(prog->aux)) {
4765 		err = bpf_prog_offload_info_fill(&info, prog);
4766 		if (err)
4767 			return err;
4768 		goto done;
4769 	}
4770 
4771 	/* NOTE: the following code is supposed to be skipped for offload.
4772 	 * bpf_prog_offload_info_fill() is the place to fill similar fields
4773 	 * for offload.
4774 	 */
4775 	ulen = info.jited_prog_len;
4776 	if (prog->aux->func_cnt) {
4777 		u32 i;
4778 
4779 		info.jited_prog_len = 0;
4780 		for (i = 0; i < prog->aux->func_cnt; i++)
4781 			info.jited_prog_len += prog->aux->func[i]->jited_len;
4782 	} else {
4783 		info.jited_prog_len = prog->jited_len;
4784 	}
4785 
4786 	if (info.jited_prog_len && ulen) {
4787 		if (bpf_dump_raw_ok(file->f_cred)) {
4788 			uinsns = u64_to_user_ptr(info.jited_prog_insns);
4789 			ulen = min_t(u32, info.jited_prog_len, ulen);
4790 
4791 			/* for multi-function programs, copy the JITed
4792 			 * instructions for all the functions
4793 			 */
4794 			if (prog->aux->func_cnt) {
4795 				u32 len, free, i;
4796 				u8 *img;
4797 
4798 				free = ulen;
4799 				for (i = 0; i < prog->aux->func_cnt; i++) {
4800 					len = prog->aux->func[i]->jited_len;
4801 					len = min_t(u32, len, free);
4802 					img = (u8 *) prog->aux->func[i]->bpf_func;
4803 					if (copy_to_user(uinsns, img, len))
4804 						return -EFAULT;
4805 					uinsns += len;
4806 					free -= len;
4807 					if (!free)
4808 						break;
4809 				}
4810 			} else {
4811 				if (copy_to_user(uinsns, prog->bpf_func, ulen))
4812 					return -EFAULT;
4813 			}
4814 		} else {
4815 			info.jited_prog_insns = 0;
4816 		}
4817 	}
4818 
4819 	ulen = info.nr_jited_ksyms;
4820 	info.nr_jited_ksyms = prog->aux->func_cnt ? : 1;
4821 	if (ulen) {
4822 		if (bpf_dump_raw_ok(file->f_cred)) {
4823 			unsigned long ksym_addr;
4824 			u64 __user *user_ksyms;
4825 			u32 i;
4826 
4827 			/* copy the address of the kernel symbol
4828 			 * corresponding to each function
4829 			 */
4830 			ulen = min_t(u32, info.nr_jited_ksyms, ulen);
4831 			user_ksyms = u64_to_user_ptr(info.jited_ksyms);
4832 			if (prog->aux->func_cnt) {
4833 				for (i = 0; i < ulen; i++) {
4834 					ksym_addr = (unsigned long)
4835 						prog->aux->func[i]->bpf_func;
4836 					if (put_user((u64) ksym_addr,
4837 						     &user_ksyms[i]))
4838 						return -EFAULT;
4839 				}
4840 			} else {
4841 				ksym_addr = (unsigned long) prog->bpf_func;
4842 				if (put_user((u64) ksym_addr, &user_ksyms[0]))
4843 					return -EFAULT;
4844 			}
4845 		} else {
4846 			info.jited_ksyms = 0;
4847 		}
4848 	}
4849 
4850 	ulen = info.nr_jited_func_lens;
4851 	info.nr_jited_func_lens = prog->aux->func_cnt ? : 1;
4852 	if (ulen) {
4853 		if (bpf_dump_raw_ok(file->f_cred)) {
4854 			u32 __user *user_lens;
4855 			u32 func_len, i;
4856 
4857 			/* copy the JITed image lengths for each function */
4858 			ulen = min_t(u32, info.nr_jited_func_lens, ulen);
4859 			user_lens = u64_to_user_ptr(info.jited_func_lens);
4860 			if (prog->aux->func_cnt) {
4861 				for (i = 0; i < ulen; i++) {
4862 					func_len =
4863 						prog->aux->func[i]->jited_len;
4864 					if (put_user(func_len, &user_lens[i]))
4865 						return -EFAULT;
4866 				}
4867 			} else {
4868 				func_len = prog->jited_len;
4869 				if (put_user(func_len, &user_lens[0]))
4870 					return -EFAULT;
4871 			}
4872 		} else {
4873 			info.jited_func_lens = 0;
4874 		}
4875 	}
4876 
4877 	if (prog->aux->btf)
4878 		info.btf_id = btf_obj_id(prog->aux->btf);
4879 	info.attach_btf_id = prog->aux->attach_btf_id;
4880 	if (attach_btf)
4881 		info.attach_btf_obj_id = btf_obj_id(attach_btf);
4882 
4883 	ulen = info.nr_func_info;
4884 	info.nr_func_info = prog->aux->func_info_cnt;
4885 	if (info.nr_func_info && ulen) {
4886 		char __user *user_finfo;
4887 
4888 		user_finfo = u64_to_user_ptr(info.func_info);
4889 		ulen = min_t(u32, info.nr_func_info, ulen);
4890 		if (copy_to_user(user_finfo, prog->aux->func_info,
4891 				 info.func_info_rec_size * ulen))
4892 			return -EFAULT;
4893 	}
4894 
4895 	ulen = info.nr_line_info;
4896 	info.nr_line_info = prog->aux->nr_linfo;
4897 	if (info.nr_line_info && ulen) {
4898 		__u8 __user *user_linfo;
4899 
4900 		user_linfo = u64_to_user_ptr(info.line_info);
4901 		ulen = min_t(u32, info.nr_line_info, ulen);
4902 		if (copy_to_user(user_linfo, prog->aux->linfo,
4903 				 info.line_info_rec_size * ulen))
4904 			return -EFAULT;
4905 	}
4906 
4907 	ulen = info.nr_jited_line_info;
4908 	if (prog->aux->jited_linfo)
4909 		info.nr_jited_line_info = prog->aux->nr_linfo;
4910 	else
4911 		info.nr_jited_line_info = 0;
4912 	if (info.nr_jited_line_info && ulen) {
4913 		if (bpf_dump_raw_ok(file->f_cred)) {
4914 			unsigned long line_addr;
4915 			__u64 __user *user_linfo;
4916 			u32 i;
4917 
4918 			user_linfo = u64_to_user_ptr(info.jited_line_info);
4919 			ulen = min_t(u32, info.nr_jited_line_info, ulen);
4920 			for (i = 0; i < ulen; i++) {
4921 				line_addr = (unsigned long)prog->aux->jited_linfo[i];
4922 				if (put_user((__u64)line_addr, &user_linfo[i]))
4923 					return -EFAULT;
4924 			}
4925 		} else {
4926 			info.jited_line_info = 0;
4927 		}
4928 	}
4929 
4930 	ulen = info.nr_prog_tags;
4931 	info.nr_prog_tags = prog->aux->func_cnt ? : 1;
4932 	if (ulen) {
4933 		__u8 __user (*user_prog_tags)[BPF_TAG_SIZE];
4934 		u32 i;
4935 
4936 		user_prog_tags = u64_to_user_ptr(info.prog_tags);
4937 		ulen = min_t(u32, info.nr_prog_tags, ulen);
4938 		if (prog->aux->func_cnt) {
4939 			for (i = 0; i < ulen; i++) {
4940 				if (copy_to_user(user_prog_tags[i],
4941 						 prog->aux->func[i]->tag,
4942 						 BPF_TAG_SIZE))
4943 					return -EFAULT;
4944 			}
4945 		} else {
4946 			if (copy_to_user(user_prog_tags[0],
4947 					 prog->tag, BPF_TAG_SIZE))
4948 				return -EFAULT;
4949 		}
4950 	}
4951 
4952 done:
4953 	if (copy_to_user(uinfo, &info, info_len) ||
4954 	    put_user(info_len, &uattr->info.info_len))
4955 		return -EFAULT;
4956 
4957 	return 0;
4958 }
4959 
4960 static int bpf_map_get_info_by_fd(struct file *file,
4961 				  struct bpf_map *map,
4962 				  const union bpf_attr *attr,
4963 				  union bpf_attr __user *uattr)
4964 {
4965 	struct bpf_map_info __user *uinfo = u64_to_user_ptr(attr->info.info);
4966 	struct bpf_map_info info;
4967 	u32 info_len = attr->info.info_len;
4968 	int err;
4969 
4970 	err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len);
4971 	if (err)
4972 		return err;
4973 	info_len = min_t(u32, sizeof(info), info_len);
4974 
4975 	memset(&info, 0, sizeof(info));
4976 	info.type = map->map_type;
4977 	info.id = map->id;
4978 	info.key_size = map->key_size;
4979 	info.value_size = map->value_size;
4980 	info.max_entries = map->max_entries;
4981 	info.map_flags = map->map_flags;
4982 	info.map_extra = map->map_extra;
4983 	memcpy(info.name, map->name, sizeof(map->name));
4984 
4985 	if (map->btf) {
4986 		info.btf_id = btf_obj_id(map->btf);
4987 		info.btf_key_type_id = map->btf_key_type_id;
4988 		info.btf_value_type_id = map->btf_value_type_id;
4989 	}
4990 	info.btf_vmlinux_value_type_id = map->btf_vmlinux_value_type_id;
4991 	if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS)
4992 		bpf_map_struct_ops_info_fill(&info, map);
4993 
4994 	if (bpf_map_is_offloaded(map)) {
4995 		err = bpf_map_offload_info_fill(&info, map);
4996 		if (err)
4997 			return err;
4998 	}
4999 
5000 	if (copy_to_user(uinfo, &info, info_len) ||
5001 	    put_user(info_len, &uattr->info.info_len))
5002 		return -EFAULT;
5003 
5004 	return 0;
5005 }
5006 
5007 static int bpf_btf_get_info_by_fd(struct file *file,
5008 				  struct btf *btf,
5009 				  const union bpf_attr *attr,
5010 				  union bpf_attr __user *uattr)
5011 {
5012 	struct bpf_btf_info __user *uinfo = u64_to_user_ptr(attr->info.info);
5013 	u32 info_len = attr->info.info_len;
5014 	int err;
5015 
5016 	err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(*uinfo), info_len);
5017 	if (err)
5018 		return err;
5019 
5020 	return btf_get_info_by_fd(btf, attr, uattr);
5021 }
5022 
5023 static int bpf_link_get_info_by_fd(struct file *file,
5024 				  struct bpf_link *link,
5025 				  const union bpf_attr *attr,
5026 				  union bpf_attr __user *uattr)
5027 {
5028 	struct bpf_link_info __user *uinfo = u64_to_user_ptr(attr->info.info);
5029 	struct bpf_link_info info;
5030 	u32 info_len = attr->info.info_len;
5031 	int err;
5032 
5033 	err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len);
5034 	if (err)
5035 		return err;
5036 	info_len = min_t(u32, sizeof(info), info_len);
5037 
5038 	memset(&info, 0, sizeof(info));
5039 	if (copy_from_user(&info, uinfo, info_len))
5040 		return -EFAULT;
5041 
5042 	info.type = link->type;
5043 	info.id = link->id;
5044 	if (link->prog)
5045 		info.prog_id = link->prog->aux->id;
5046 
5047 	if (link->ops->fill_link_info) {
5048 		err = link->ops->fill_link_info(link, &info);
5049 		if (err)
5050 			return err;
5051 	}
5052 
5053 	if (copy_to_user(uinfo, &info, info_len) ||
5054 	    put_user(info_len, &uattr->info.info_len))
5055 		return -EFAULT;
5056 
5057 	return 0;
5058 }
5059 
5060 
5061 #define BPF_OBJ_GET_INFO_BY_FD_LAST_FIELD info.info
5062 
5063 static int bpf_obj_get_info_by_fd(const union bpf_attr *attr,
5064 				  union bpf_attr __user *uattr)
5065 {
5066 	if (CHECK_ATTR(BPF_OBJ_GET_INFO_BY_FD))
5067 		return -EINVAL;
5068 
5069 	CLASS(fd, f)(attr->info.bpf_fd);
5070 	if (fd_empty(f))
5071 		return -EBADFD;
5072 
5073 	if (fd_file(f)->f_op == &bpf_prog_fops)
5074 		return bpf_prog_get_info_by_fd(fd_file(f), fd_file(f)->private_data, attr,
5075 					      uattr);
5076 	else if (fd_file(f)->f_op == &bpf_map_fops)
5077 		return bpf_map_get_info_by_fd(fd_file(f), fd_file(f)->private_data, attr,
5078 					     uattr);
5079 	else if (fd_file(f)->f_op == &btf_fops)
5080 		return bpf_btf_get_info_by_fd(fd_file(f), fd_file(f)->private_data, attr, uattr);
5081 	else if (fd_file(f)->f_op == &bpf_link_fops || fd_file(f)->f_op == &bpf_link_fops_poll)
5082 		return bpf_link_get_info_by_fd(fd_file(f), fd_file(f)->private_data,
5083 					      attr, uattr);
5084 	return -EINVAL;
5085 }
5086 
5087 #define BPF_BTF_LOAD_LAST_FIELD btf_token_fd
5088 
5089 static int bpf_btf_load(const union bpf_attr *attr, bpfptr_t uattr, __u32 uattr_size)
5090 {
5091 	struct bpf_token *token = NULL;
5092 
5093 	if (CHECK_ATTR(BPF_BTF_LOAD))
5094 		return -EINVAL;
5095 
5096 	if (attr->btf_flags & ~BPF_F_TOKEN_FD)
5097 		return -EINVAL;
5098 
5099 	if (attr->btf_flags & BPF_F_TOKEN_FD) {
5100 		token = bpf_token_get_from_fd(attr->btf_token_fd);
5101 		if (IS_ERR(token))
5102 			return PTR_ERR(token);
5103 		if (!bpf_token_allow_cmd(token, BPF_BTF_LOAD)) {
5104 			bpf_token_put(token);
5105 			token = NULL;
5106 		}
5107 	}
5108 
5109 	if (!bpf_token_capable(token, CAP_BPF)) {
5110 		bpf_token_put(token);
5111 		return -EPERM;
5112 	}
5113 
5114 	bpf_token_put(token);
5115 
5116 	return btf_new_fd(attr, uattr, uattr_size);
5117 }
5118 
5119 #define BPF_BTF_GET_FD_BY_ID_LAST_FIELD btf_id
5120 
5121 static int bpf_btf_get_fd_by_id(const union bpf_attr *attr)
5122 {
5123 	if (CHECK_ATTR(BPF_BTF_GET_FD_BY_ID))
5124 		return -EINVAL;
5125 
5126 	if (!capable(CAP_SYS_ADMIN))
5127 		return -EPERM;
5128 
5129 	return btf_get_fd_by_id(attr->btf_id);
5130 }
5131 
5132 static int bpf_task_fd_query_copy(const union bpf_attr *attr,
5133 				    union bpf_attr __user *uattr,
5134 				    u32 prog_id, u32 fd_type,
5135 				    const char *buf, u64 probe_offset,
5136 				    u64 probe_addr)
5137 {
5138 	char __user *ubuf = u64_to_user_ptr(attr->task_fd_query.buf);
5139 	u32 len = buf ? strlen(buf) : 0, input_len;
5140 	int err = 0;
5141 
5142 	if (put_user(len, &uattr->task_fd_query.buf_len))
5143 		return -EFAULT;
5144 	input_len = attr->task_fd_query.buf_len;
5145 	if (input_len && ubuf) {
5146 		if (!len) {
5147 			/* nothing to copy, just make ubuf NULL terminated */
5148 			char zero = '\0';
5149 
5150 			if (put_user(zero, ubuf))
5151 				return -EFAULT;
5152 		} else if (input_len >= len + 1) {
5153 			/* ubuf can hold the string with NULL terminator */
5154 			if (copy_to_user(ubuf, buf, len + 1))
5155 				return -EFAULT;
5156 		} else {
5157 			/* ubuf cannot hold the string with NULL terminator,
5158 			 * do a partial copy with NULL terminator.
5159 			 */
5160 			char zero = '\0';
5161 
5162 			err = -ENOSPC;
5163 			if (copy_to_user(ubuf, buf, input_len - 1))
5164 				return -EFAULT;
5165 			if (put_user(zero, ubuf + input_len - 1))
5166 				return -EFAULT;
5167 		}
5168 	}
5169 
5170 	if (put_user(prog_id, &uattr->task_fd_query.prog_id) ||
5171 	    put_user(fd_type, &uattr->task_fd_query.fd_type) ||
5172 	    put_user(probe_offset, &uattr->task_fd_query.probe_offset) ||
5173 	    put_user(probe_addr, &uattr->task_fd_query.probe_addr))
5174 		return -EFAULT;
5175 
5176 	return err;
5177 }
5178 
5179 #define BPF_TASK_FD_QUERY_LAST_FIELD task_fd_query.probe_addr
5180 
5181 static int bpf_task_fd_query(const union bpf_attr *attr,
5182 			     union bpf_attr __user *uattr)
5183 {
5184 	pid_t pid = attr->task_fd_query.pid;
5185 	u32 fd = attr->task_fd_query.fd;
5186 	const struct perf_event *event;
5187 	struct task_struct *task;
5188 	struct file *file;
5189 	int err;
5190 
5191 	if (CHECK_ATTR(BPF_TASK_FD_QUERY))
5192 		return -EINVAL;
5193 
5194 	if (!capable(CAP_SYS_ADMIN))
5195 		return -EPERM;
5196 
5197 	if (attr->task_fd_query.flags != 0)
5198 		return -EINVAL;
5199 
5200 	rcu_read_lock();
5201 	task = get_pid_task(find_vpid(pid), PIDTYPE_PID);
5202 	rcu_read_unlock();
5203 	if (!task)
5204 		return -ENOENT;
5205 
5206 	err = 0;
5207 	file = fget_task(task, fd);
5208 	put_task_struct(task);
5209 	if (!file)
5210 		return -EBADF;
5211 
5212 	if (file->f_op == &bpf_link_fops || file->f_op == &bpf_link_fops_poll) {
5213 		struct bpf_link *link = file->private_data;
5214 
5215 		if (link->ops == &bpf_raw_tp_link_lops) {
5216 			struct bpf_raw_tp_link *raw_tp =
5217 				container_of(link, struct bpf_raw_tp_link, link);
5218 			struct bpf_raw_event_map *btp = raw_tp->btp;
5219 
5220 			err = bpf_task_fd_query_copy(attr, uattr,
5221 						     raw_tp->link.prog->aux->id,
5222 						     BPF_FD_TYPE_RAW_TRACEPOINT,
5223 						     btp->tp->name, 0, 0);
5224 			goto put_file;
5225 		}
5226 		goto out_not_supp;
5227 	}
5228 
5229 	event = perf_get_event(file);
5230 	if (!IS_ERR(event)) {
5231 		u64 probe_offset, probe_addr;
5232 		u32 prog_id, fd_type;
5233 		const char *buf;
5234 
5235 		err = bpf_get_perf_event_info(event, &prog_id, &fd_type,
5236 					      &buf, &probe_offset,
5237 					      &probe_addr, NULL);
5238 		if (!err)
5239 			err = bpf_task_fd_query_copy(attr, uattr, prog_id,
5240 						     fd_type, buf,
5241 						     probe_offset,
5242 						     probe_addr);
5243 		goto put_file;
5244 	}
5245 
5246 out_not_supp:
5247 	err = -ENOTSUPP;
5248 put_file:
5249 	fput(file);
5250 	return err;
5251 }
5252 
5253 #define BPF_MAP_BATCH_LAST_FIELD batch.flags
5254 
5255 #define BPF_DO_BATCH(fn, ...)			\
5256 	do {					\
5257 		if (!fn) {			\
5258 			err = -ENOTSUPP;	\
5259 			goto err_put;		\
5260 		}				\
5261 		err = fn(__VA_ARGS__);		\
5262 	} while (0)
5263 
5264 static int bpf_map_do_batch(const union bpf_attr *attr,
5265 			    union bpf_attr __user *uattr,
5266 			    int cmd)
5267 {
5268 	bool has_read  = cmd == BPF_MAP_LOOKUP_BATCH ||
5269 			 cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH;
5270 	bool has_write = cmd != BPF_MAP_LOOKUP_BATCH;
5271 	struct bpf_map *map;
5272 	int err;
5273 
5274 	if (CHECK_ATTR(BPF_MAP_BATCH))
5275 		return -EINVAL;
5276 
5277 	CLASS(fd, f)(attr->batch.map_fd);
5278 
5279 	map = __bpf_map_get(f);
5280 	if (IS_ERR(map))
5281 		return PTR_ERR(map);
5282 	if (has_write)
5283 		bpf_map_write_active_inc(map);
5284 	if (has_read && !(map_get_sys_perms(map, f) & FMODE_CAN_READ)) {
5285 		err = -EPERM;
5286 		goto err_put;
5287 	}
5288 	if (has_write && !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
5289 		err = -EPERM;
5290 		goto err_put;
5291 	}
5292 
5293 	if (cmd == BPF_MAP_LOOKUP_BATCH)
5294 		BPF_DO_BATCH(map->ops->map_lookup_batch, map, attr, uattr);
5295 	else if (cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH)
5296 		BPF_DO_BATCH(map->ops->map_lookup_and_delete_batch, map, attr, uattr);
5297 	else if (cmd == BPF_MAP_UPDATE_BATCH)
5298 		BPF_DO_BATCH(map->ops->map_update_batch, map, fd_file(f), attr, uattr);
5299 	else
5300 		BPF_DO_BATCH(map->ops->map_delete_batch, map, attr, uattr);
5301 err_put:
5302 	if (has_write) {
5303 		maybe_wait_bpf_programs(map);
5304 		bpf_map_write_active_dec(map);
5305 	}
5306 	return err;
5307 }
5308 
5309 #define BPF_LINK_CREATE_LAST_FIELD link_create.uprobe_multi.pid
5310 static int link_create(union bpf_attr *attr, bpfptr_t uattr)
5311 {
5312 	struct bpf_prog *prog;
5313 	int ret;
5314 
5315 	if (CHECK_ATTR(BPF_LINK_CREATE))
5316 		return -EINVAL;
5317 
5318 	if (attr->link_create.attach_type == BPF_STRUCT_OPS)
5319 		return bpf_struct_ops_link_create(attr);
5320 
5321 	prog = bpf_prog_get(attr->link_create.prog_fd);
5322 	if (IS_ERR(prog))
5323 		return PTR_ERR(prog);
5324 
5325 	ret = bpf_prog_attach_check_attach_type(prog,
5326 						attr->link_create.attach_type);
5327 	if (ret)
5328 		goto out;
5329 
5330 	switch (prog->type) {
5331 	case BPF_PROG_TYPE_CGROUP_SKB:
5332 	case BPF_PROG_TYPE_CGROUP_SOCK:
5333 	case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
5334 	case BPF_PROG_TYPE_SOCK_OPS:
5335 	case BPF_PROG_TYPE_CGROUP_DEVICE:
5336 	case BPF_PROG_TYPE_CGROUP_SYSCTL:
5337 	case BPF_PROG_TYPE_CGROUP_SOCKOPT:
5338 		ret = cgroup_bpf_link_attach(attr, prog);
5339 		break;
5340 	case BPF_PROG_TYPE_EXT:
5341 		ret = bpf_tracing_prog_attach(prog,
5342 					      attr->link_create.target_fd,
5343 					      attr->link_create.target_btf_id,
5344 					      attr->link_create.tracing.cookie);
5345 		break;
5346 	case BPF_PROG_TYPE_LSM:
5347 	case BPF_PROG_TYPE_TRACING:
5348 		if (attr->link_create.attach_type != prog->expected_attach_type) {
5349 			ret = -EINVAL;
5350 			goto out;
5351 		}
5352 		if (prog->expected_attach_type == BPF_TRACE_RAW_TP)
5353 			ret = bpf_raw_tp_link_attach(prog, NULL, attr->link_create.tracing.cookie);
5354 		else if (prog->expected_attach_type == BPF_TRACE_ITER)
5355 			ret = bpf_iter_link_attach(attr, uattr, prog);
5356 		else if (prog->expected_attach_type == BPF_LSM_CGROUP)
5357 			ret = cgroup_bpf_link_attach(attr, prog);
5358 		else
5359 			ret = bpf_tracing_prog_attach(prog,
5360 						      attr->link_create.target_fd,
5361 						      attr->link_create.target_btf_id,
5362 						      attr->link_create.tracing.cookie);
5363 		break;
5364 	case BPF_PROG_TYPE_FLOW_DISSECTOR:
5365 	case BPF_PROG_TYPE_SK_LOOKUP:
5366 		ret = netns_bpf_link_create(attr, prog);
5367 		break;
5368 	case BPF_PROG_TYPE_SK_MSG:
5369 	case BPF_PROG_TYPE_SK_SKB:
5370 		ret = sock_map_link_create(attr, prog);
5371 		break;
5372 #ifdef CONFIG_NET
5373 	case BPF_PROG_TYPE_XDP:
5374 		ret = bpf_xdp_link_attach(attr, prog);
5375 		break;
5376 	case BPF_PROG_TYPE_SCHED_CLS:
5377 		if (attr->link_create.attach_type == BPF_TCX_INGRESS ||
5378 		    attr->link_create.attach_type == BPF_TCX_EGRESS)
5379 			ret = tcx_link_attach(attr, prog);
5380 		else
5381 			ret = netkit_link_attach(attr, prog);
5382 		break;
5383 	case BPF_PROG_TYPE_NETFILTER:
5384 		ret = bpf_nf_link_attach(attr, prog);
5385 		break;
5386 #endif
5387 	case BPF_PROG_TYPE_PERF_EVENT:
5388 	case BPF_PROG_TYPE_TRACEPOINT:
5389 		ret = bpf_perf_link_attach(attr, prog);
5390 		break;
5391 	case BPF_PROG_TYPE_KPROBE:
5392 		if (attr->link_create.attach_type == BPF_PERF_EVENT)
5393 			ret = bpf_perf_link_attach(attr, prog);
5394 		else if (attr->link_create.attach_type == BPF_TRACE_KPROBE_MULTI ||
5395 			 attr->link_create.attach_type == BPF_TRACE_KPROBE_SESSION)
5396 			ret = bpf_kprobe_multi_link_attach(attr, prog);
5397 		else if (attr->link_create.attach_type == BPF_TRACE_UPROBE_MULTI ||
5398 			 attr->link_create.attach_type == BPF_TRACE_UPROBE_SESSION)
5399 			ret = bpf_uprobe_multi_link_attach(attr, prog);
5400 		break;
5401 	default:
5402 		ret = -EINVAL;
5403 	}
5404 
5405 out:
5406 	if (ret < 0)
5407 		bpf_prog_put(prog);
5408 	return ret;
5409 }
5410 
5411 static int link_update_map(struct bpf_link *link, union bpf_attr *attr)
5412 {
5413 	struct bpf_map *new_map, *old_map = NULL;
5414 	int ret;
5415 
5416 	new_map = bpf_map_get(attr->link_update.new_map_fd);
5417 	if (IS_ERR(new_map))
5418 		return PTR_ERR(new_map);
5419 
5420 	if (attr->link_update.flags & BPF_F_REPLACE) {
5421 		old_map = bpf_map_get(attr->link_update.old_map_fd);
5422 		if (IS_ERR(old_map)) {
5423 			ret = PTR_ERR(old_map);
5424 			goto out_put;
5425 		}
5426 	} else if (attr->link_update.old_map_fd) {
5427 		ret = -EINVAL;
5428 		goto out_put;
5429 	}
5430 
5431 	ret = link->ops->update_map(link, new_map, old_map);
5432 
5433 	if (old_map)
5434 		bpf_map_put(old_map);
5435 out_put:
5436 	bpf_map_put(new_map);
5437 	return ret;
5438 }
5439 
5440 #define BPF_LINK_UPDATE_LAST_FIELD link_update.old_prog_fd
5441 
5442 static int link_update(union bpf_attr *attr)
5443 {
5444 	struct bpf_prog *old_prog = NULL, *new_prog;
5445 	struct bpf_link *link;
5446 	u32 flags;
5447 	int ret;
5448 
5449 	if (CHECK_ATTR(BPF_LINK_UPDATE))
5450 		return -EINVAL;
5451 
5452 	flags = attr->link_update.flags;
5453 	if (flags & ~BPF_F_REPLACE)
5454 		return -EINVAL;
5455 
5456 	link = bpf_link_get_from_fd(attr->link_update.link_fd);
5457 	if (IS_ERR(link))
5458 		return PTR_ERR(link);
5459 
5460 	if (link->ops->update_map) {
5461 		ret = link_update_map(link, attr);
5462 		goto out_put_link;
5463 	}
5464 
5465 	new_prog = bpf_prog_get(attr->link_update.new_prog_fd);
5466 	if (IS_ERR(new_prog)) {
5467 		ret = PTR_ERR(new_prog);
5468 		goto out_put_link;
5469 	}
5470 
5471 	if (flags & BPF_F_REPLACE) {
5472 		old_prog = bpf_prog_get(attr->link_update.old_prog_fd);
5473 		if (IS_ERR(old_prog)) {
5474 			ret = PTR_ERR(old_prog);
5475 			old_prog = NULL;
5476 			goto out_put_progs;
5477 		}
5478 	} else if (attr->link_update.old_prog_fd) {
5479 		ret = -EINVAL;
5480 		goto out_put_progs;
5481 	}
5482 
5483 	if (link->ops->update_prog)
5484 		ret = link->ops->update_prog(link, new_prog, old_prog);
5485 	else
5486 		ret = -EINVAL;
5487 
5488 out_put_progs:
5489 	if (old_prog)
5490 		bpf_prog_put(old_prog);
5491 	if (ret)
5492 		bpf_prog_put(new_prog);
5493 out_put_link:
5494 	bpf_link_put_direct(link);
5495 	return ret;
5496 }
5497 
5498 #define BPF_LINK_DETACH_LAST_FIELD link_detach.link_fd
5499 
5500 static int link_detach(union bpf_attr *attr)
5501 {
5502 	struct bpf_link *link;
5503 	int ret;
5504 
5505 	if (CHECK_ATTR(BPF_LINK_DETACH))
5506 		return -EINVAL;
5507 
5508 	link = bpf_link_get_from_fd(attr->link_detach.link_fd);
5509 	if (IS_ERR(link))
5510 		return PTR_ERR(link);
5511 
5512 	if (link->ops->detach)
5513 		ret = link->ops->detach(link);
5514 	else
5515 		ret = -EOPNOTSUPP;
5516 
5517 	bpf_link_put_direct(link);
5518 	return ret;
5519 }
5520 
5521 struct bpf_link *bpf_link_inc_not_zero(struct bpf_link *link)
5522 {
5523 	return atomic64_fetch_add_unless(&link->refcnt, 1, 0) ? link : ERR_PTR(-ENOENT);
5524 }
5525 EXPORT_SYMBOL(bpf_link_inc_not_zero);
5526 
5527 struct bpf_link *bpf_link_by_id(u32 id)
5528 {
5529 	struct bpf_link *link;
5530 
5531 	if (!id)
5532 		return ERR_PTR(-ENOENT);
5533 
5534 	spin_lock_bh(&link_idr_lock);
5535 	/* before link is "settled", ID is 0, pretend it doesn't exist yet */
5536 	link = idr_find(&link_idr, id);
5537 	if (link) {
5538 		if (link->id)
5539 			link = bpf_link_inc_not_zero(link);
5540 		else
5541 			link = ERR_PTR(-EAGAIN);
5542 	} else {
5543 		link = ERR_PTR(-ENOENT);
5544 	}
5545 	spin_unlock_bh(&link_idr_lock);
5546 	return link;
5547 }
5548 
5549 struct bpf_link *bpf_link_get_curr_or_next(u32 *id)
5550 {
5551 	struct bpf_link *link;
5552 
5553 	spin_lock_bh(&link_idr_lock);
5554 again:
5555 	link = idr_get_next(&link_idr, id);
5556 	if (link) {
5557 		link = bpf_link_inc_not_zero(link);
5558 		if (IS_ERR(link)) {
5559 			(*id)++;
5560 			goto again;
5561 		}
5562 	}
5563 	spin_unlock_bh(&link_idr_lock);
5564 
5565 	return link;
5566 }
5567 
5568 #define BPF_LINK_GET_FD_BY_ID_LAST_FIELD link_id
5569 
5570 static int bpf_link_get_fd_by_id(const union bpf_attr *attr)
5571 {
5572 	struct bpf_link *link;
5573 	u32 id = attr->link_id;
5574 	int fd;
5575 
5576 	if (CHECK_ATTR(BPF_LINK_GET_FD_BY_ID))
5577 		return -EINVAL;
5578 
5579 	if (!capable(CAP_SYS_ADMIN))
5580 		return -EPERM;
5581 
5582 	link = bpf_link_by_id(id);
5583 	if (IS_ERR(link))
5584 		return PTR_ERR(link);
5585 
5586 	fd = bpf_link_new_fd(link);
5587 	if (fd < 0)
5588 		bpf_link_put_direct(link);
5589 
5590 	return fd;
5591 }
5592 
5593 DEFINE_MUTEX(bpf_stats_enabled_mutex);
5594 
5595 static int bpf_stats_release(struct inode *inode, struct file *file)
5596 {
5597 	mutex_lock(&bpf_stats_enabled_mutex);
5598 	static_key_slow_dec(&bpf_stats_enabled_key.key);
5599 	mutex_unlock(&bpf_stats_enabled_mutex);
5600 	return 0;
5601 }
5602 
5603 static const struct file_operations bpf_stats_fops = {
5604 	.release = bpf_stats_release,
5605 };
5606 
5607 static int bpf_enable_runtime_stats(void)
5608 {
5609 	int fd;
5610 
5611 	mutex_lock(&bpf_stats_enabled_mutex);
5612 
5613 	/* Set a very high limit to avoid overflow */
5614 	if (static_key_count(&bpf_stats_enabled_key.key) > INT_MAX / 2) {
5615 		mutex_unlock(&bpf_stats_enabled_mutex);
5616 		return -EBUSY;
5617 	}
5618 
5619 	fd = anon_inode_getfd("bpf-stats", &bpf_stats_fops, NULL, O_CLOEXEC);
5620 	if (fd >= 0)
5621 		static_key_slow_inc(&bpf_stats_enabled_key.key);
5622 
5623 	mutex_unlock(&bpf_stats_enabled_mutex);
5624 	return fd;
5625 }
5626 
5627 #define BPF_ENABLE_STATS_LAST_FIELD enable_stats.type
5628 
5629 static int bpf_enable_stats(union bpf_attr *attr)
5630 {
5631 
5632 	if (CHECK_ATTR(BPF_ENABLE_STATS))
5633 		return -EINVAL;
5634 
5635 	if (!capable(CAP_SYS_ADMIN))
5636 		return -EPERM;
5637 
5638 	switch (attr->enable_stats.type) {
5639 	case BPF_STATS_RUN_TIME:
5640 		return bpf_enable_runtime_stats();
5641 	default:
5642 		break;
5643 	}
5644 	return -EINVAL;
5645 }
5646 
5647 #define BPF_ITER_CREATE_LAST_FIELD iter_create.flags
5648 
5649 static int bpf_iter_create(union bpf_attr *attr)
5650 {
5651 	struct bpf_link *link;
5652 	int err;
5653 
5654 	if (CHECK_ATTR(BPF_ITER_CREATE))
5655 		return -EINVAL;
5656 
5657 	if (attr->iter_create.flags)
5658 		return -EINVAL;
5659 
5660 	link = bpf_link_get_from_fd(attr->iter_create.link_fd);
5661 	if (IS_ERR(link))
5662 		return PTR_ERR(link);
5663 
5664 	err = bpf_iter_new_fd(link);
5665 	bpf_link_put_direct(link);
5666 
5667 	return err;
5668 }
5669 
5670 #define BPF_PROG_BIND_MAP_LAST_FIELD prog_bind_map.flags
5671 
5672 static int bpf_prog_bind_map(union bpf_attr *attr)
5673 {
5674 	struct bpf_prog *prog;
5675 	struct bpf_map *map;
5676 	struct bpf_map **used_maps_old, **used_maps_new;
5677 	int i, ret = 0;
5678 
5679 	if (CHECK_ATTR(BPF_PROG_BIND_MAP))
5680 		return -EINVAL;
5681 
5682 	if (attr->prog_bind_map.flags)
5683 		return -EINVAL;
5684 
5685 	prog = bpf_prog_get(attr->prog_bind_map.prog_fd);
5686 	if (IS_ERR(prog))
5687 		return PTR_ERR(prog);
5688 
5689 	map = bpf_map_get(attr->prog_bind_map.map_fd);
5690 	if (IS_ERR(map)) {
5691 		ret = PTR_ERR(map);
5692 		goto out_prog_put;
5693 	}
5694 
5695 	mutex_lock(&prog->aux->used_maps_mutex);
5696 
5697 	used_maps_old = prog->aux->used_maps;
5698 
5699 	for (i = 0; i < prog->aux->used_map_cnt; i++)
5700 		if (used_maps_old[i] == map) {
5701 			bpf_map_put(map);
5702 			goto out_unlock;
5703 		}
5704 
5705 	used_maps_new = kmalloc_array(prog->aux->used_map_cnt + 1,
5706 				      sizeof(used_maps_new[0]),
5707 				      GFP_KERNEL);
5708 	if (!used_maps_new) {
5709 		ret = -ENOMEM;
5710 		goto out_unlock;
5711 	}
5712 
5713 	/* The bpf program will not access the bpf map, but for the sake of
5714 	 * simplicity, increase sleepable_refcnt for sleepable program as well.
5715 	 */
5716 	if (prog->sleepable)
5717 		atomic64_inc(&map->sleepable_refcnt);
5718 	memcpy(used_maps_new, used_maps_old,
5719 	       sizeof(used_maps_old[0]) * prog->aux->used_map_cnt);
5720 	used_maps_new[prog->aux->used_map_cnt] = map;
5721 
5722 	prog->aux->used_map_cnt++;
5723 	prog->aux->used_maps = used_maps_new;
5724 
5725 	kfree(used_maps_old);
5726 
5727 out_unlock:
5728 	mutex_unlock(&prog->aux->used_maps_mutex);
5729 
5730 	if (ret)
5731 		bpf_map_put(map);
5732 out_prog_put:
5733 	bpf_prog_put(prog);
5734 	return ret;
5735 }
5736 
5737 #define BPF_TOKEN_CREATE_LAST_FIELD token_create.bpffs_fd
5738 
5739 static int token_create(union bpf_attr *attr)
5740 {
5741 	if (CHECK_ATTR(BPF_TOKEN_CREATE))
5742 		return -EINVAL;
5743 
5744 	/* no flags are supported yet */
5745 	if (attr->token_create.flags)
5746 		return -EINVAL;
5747 
5748 	return bpf_token_create(attr);
5749 }
5750 
5751 static int __sys_bpf(enum bpf_cmd cmd, bpfptr_t uattr, unsigned int size)
5752 {
5753 	union bpf_attr attr;
5754 	int err;
5755 
5756 	err = bpf_check_uarg_tail_zero(uattr, sizeof(attr), size);
5757 	if (err)
5758 		return err;
5759 	size = min_t(u32, size, sizeof(attr));
5760 
5761 	/* copy attributes from user space, may be less than sizeof(bpf_attr) */
5762 	memset(&attr, 0, sizeof(attr));
5763 	if (copy_from_bpfptr(&attr, uattr, size) != 0)
5764 		return -EFAULT;
5765 
5766 	err = security_bpf(cmd, &attr, size);
5767 	if (err < 0)
5768 		return err;
5769 
5770 	switch (cmd) {
5771 	case BPF_MAP_CREATE:
5772 		err = map_create(&attr);
5773 		break;
5774 	case BPF_MAP_LOOKUP_ELEM:
5775 		err = map_lookup_elem(&attr);
5776 		break;
5777 	case BPF_MAP_UPDATE_ELEM:
5778 		err = map_update_elem(&attr, uattr);
5779 		break;
5780 	case BPF_MAP_DELETE_ELEM:
5781 		err = map_delete_elem(&attr, uattr);
5782 		break;
5783 	case BPF_MAP_GET_NEXT_KEY:
5784 		err = map_get_next_key(&attr);
5785 		break;
5786 	case BPF_MAP_FREEZE:
5787 		err = map_freeze(&attr);
5788 		break;
5789 	case BPF_PROG_LOAD:
5790 		err = bpf_prog_load(&attr, uattr, size);
5791 		break;
5792 	case BPF_OBJ_PIN:
5793 		err = bpf_obj_pin(&attr);
5794 		break;
5795 	case BPF_OBJ_GET:
5796 		err = bpf_obj_get(&attr);
5797 		break;
5798 	case BPF_PROG_ATTACH:
5799 		err = bpf_prog_attach(&attr);
5800 		break;
5801 	case BPF_PROG_DETACH:
5802 		err = bpf_prog_detach(&attr);
5803 		break;
5804 	case BPF_PROG_QUERY:
5805 		err = bpf_prog_query(&attr, uattr.user);
5806 		break;
5807 	case BPF_PROG_TEST_RUN:
5808 		err = bpf_prog_test_run(&attr, uattr.user);
5809 		break;
5810 	case BPF_PROG_GET_NEXT_ID:
5811 		err = bpf_obj_get_next_id(&attr, uattr.user,
5812 					  &prog_idr, &prog_idr_lock);
5813 		break;
5814 	case BPF_MAP_GET_NEXT_ID:
5815 		err = bpf_obj_get_next_id(&attr, uattr.user,
5816 					  &map_idr, &map_idr_lock);
5817 		break;
5818 	case BPF_BTF_GET_NEXT_ID:
5819 		err = bpf_obj_get_next_id(&attr, uattr.user,
5820 					  &btf_idr, &btf_idr_lock);
5821 		break;
5822 	case BPF_PROG_GET_FD_BY_ID:
5823 		err = bpf_prog_get_fd_by_id(&attr);
5824 		break;
5825 	case BPF_MAP_GET_FD_BY_ID:
5826 		err = bpf_map_get_fd_by_id(&attr);
5827 		break;
5828 	case BPF_OBJ_GET_INFO_BY_FD:
5829 		err = bpf_obj_get_info_by_fd(&attr, uattr.user);
5830 		break;
5831 	case BPF_RAW_TRACEPOINT_OPEN:
5832 		err = bpf_raw_tracepoint_open(&attr);
5833 		break;
5834 	case BPF_BTF_LOAD:
5835 		err = bpf_btf_load(&attr, uattr, size);
5836 		break;
5837 	case BPF_BTF_GET_FD_BY_ID:
5838 		err = bpf_btf_get_fd_by_id(&attr);
5839 		break;
5840 	case BPF_TASK_FD_QUERY:
5841 		err = bpf_task_fd_query(&attr, uattr.user);
5842 		break;
5843 	case BPF_MAP_LOOKUP_AND_DELETE_ELEM:
5844 		err = map_lookup_and_delete_elem(&attr);
5845 		break;
5846 	case BPF_MAP_LOOKUP_BATCH:
5847 		err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_LOOKUP_BATCH);
5848 		break;
5849 	case BPF_MAP_LOOKUP_AND_DELETE_BATCH:
5850 		err = bpf_map_do_batch(&attr, uattr.user,
5851 				       BPF_MAP_LOOKUP_AND_DELETE_BATCH);
5852 		break;
5853 	case BPF_MAP_UPDATE_BATCH:
5854 		err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_UPDATE_BATCH);
5855 		break;
5856 	case BPF_MAP_DELETE_BATCH:
5857 		err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_DELETE_BATCH);
5858 		break;
5859 	case BPF_LINK_CREATE:
5860 		err = link_create(&attr, uattr);
5861 		break;
5862 	case BPF_LINK_UPDATE:
5863 		err = link_update(&attr);
5864 		break;
5865 	case BPF_LINK_GET_FD_BY_ID:
5866 		err = bpf_link_get_fd_by_id(&attr);
5867 		break;
5868 	case BPF_LINK_GET_NEXT_ID:
5869 		err = bpf_obj_get_next_id(&attr, uattr.user,
5870 					  &link_idr, &link_idr_lock);
5871 		break;
5872 	case BPF_ENABLE_STATS:
5873 		err = bpf_enable_stats(&attr);
5874 		break;
5875 	case BPF_ITER_CREATE:
5876 		err = bpf_iter_create(&attr);
5877 		break;
5878 	case BPF_LINK_DETACH:
5879 		err = link_detach(&attr);
5880 		break;
5881 	case BPF_PROG_BIND_MAP:
5882 		err = bpf_prog_bind_map(&attr);
5883 		break;
5884 	case BPF_TOKEN_CREATE:
5885 		err = token_create(&attr);
5886 		break;
5887 	default:
5888 		err = -EINVAL;
5889 		break;
5890 	}
5891 
5892 	return err;
5893 }
5894 
5895 SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size)
5896 {
5897 	return __sys_bpf(cmd, USER_BPFPTR(uattr), size);
5898 }
5899 
5900 static bool syscall_prog_is_valid_access(int off, int size,
5901 					 enum bpf_access_type type,
5902 					 const struct bpf_prog *prog,
5903 					 struct bpf_insn_access_aux *info)
5904 {
5905 	if (off < 0 || off >= U16_MAX)
5906 		return false;
5907 	if (off % size != 0)
5908 		return false;
5909 	return true;
5910 }
5911 
5912 BPF_CALL_3(bpf_sys_bpf, int, cmd, union bpf_attr *, attr, u32, attr_size)
5913 {
5914 	switch (cmd) {
5915 	case BPF_MAP_CREATE:
5916 	case BPF_MAP_DELETE_ELEM:
5917 	case BPF_MAP_UPDATE_ELEM:
5918 	case BPF_MAP_FREEZE:
5919 	case BPF_MAP_GET_FD_BY_ID:
5920 	case BPF_PROG_LOAD:
5921 	case BPF_BTF_LOAD:
5922 	case BPF_LINK_CREATE:
5923 	case BPF_RAW_TRACEPOINT_OPEN:
5924 		break;
5925 	default:
5926 		return -EINVAL;
5927 	}
5928 	return __sys_bpf(cmd, KERNEL_BPFPTR(attr), attr_size);
5929 }
5930 
5931 
5932 /* To shut up -Wmissing-prototypes.
5933  * This function is used by the kernel light skeleton
5934  * to load bpf programs when modules are loaded or during kernel boot.
5935  * See tools/lib/bpf/skel_internal.h
5936  */
5937 int kern_sys_bpf(int cmd, union bpf_attr *attr, unsigned int size);
5938 
5939 int kern_sys_bpf(int cmd, union bpf_attr *attr, unsigned int size)
5940 {
5941 	struct bpf_prog * __maybe_unused prog;
5942 	struct bpf_tramp_run_ctx __maybe_unused run_ctx;
5943 
5944 	switch (cmd) {
5945 #ifdef CONFIG_BPF_JIT /* __bpf_prog_enter_sleepable used by trampoline and JIT */
5946 	case BPF_PROG_TEST_RUN:
5947 		if (attr->test.data_in || attr->test.data_out ||
5948 		    attr->test.ctx_out || attr->test.duration ||
5949 		    attr->test.repeat || attr->test.flags)
5950 			return -EINVAL;
5951 
5952 		prog = bpf_prog_get_type(attr->test.prog_fd, BPF_PROG_TYPE_SYSCALL);
5953 		if (IS_ERR(prog))
5954 			return PTR_ERR(prog);
5955 
5956 		if (attr->test.ctx_size_in < prog->aux->max_ctx_offset ||
5957 		    attr->test.ctx_size_in > U16_MAX) {
5958 			bpf_prog_put(prog);
5959 			return -EINVAL;
5960 		}
5961 
5962 		run_ctx.bpf_cookie = 0;
5963 		if (!__bpf_prog_enter_sleepable_recur(prog, &run_ctx)) {
5964 			/* recursion detected */
5965 			__bpf_prog_exit_sleepable_recur(prog, 0, &run_ctx);
5966 			bpf_prog_put(prog);
5967 			return -EBUSY;
5968 		}
5969 		attr->test.retval = bpf_prog_run(prog, (void *) (long) attr->test.ctx_in);
5970 		__bpf_prog_exit_sleepable_recur(prog, 0 /* bpf_prog_run does runtime stats */,
5971 						&run_ctx);
5972 		bpf_prog_put(prog);
5973 		return 0;
5974 #endif
5975 	default:
5976 		return ____bpf_sys_bpf(cmd, attr, size);
5977 	}
5978 }
5979 EXPORT_SYMBOL(kern_sys_bpf);
5980 
5981 static const struct bpf_func_proto bpf_sys_bpf_proto = {
5982 	.func		= bpf_sys_bpf,
5983 	.gpl_only	= false,
5984 	.ret_type	= RET_INTEGER,
5985 	.arg1_type	= ARG_ANYTHING,
5986 	.arg2_type	= ARG_PTR_TO_MEM | MEM_RDONLY,
5987 	.arg3_type	= ARG_CONST_SIZE,
5988 };
5989 
5990 const struct bpf_func_proto * __weak
5991 tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
5992 {
5993 	return bpf_base_func_proto(func_id, prog);
5994 }
5995 
5996 BPF_CALL_1(bpf_sys_close, u32, fd)
5997 {
5998 	/* When bpf program calls this helper there should not be
5999 	 * an fdget() without matching completed fdput().
6000 	 * This helper is allowed in the following callchain only:
6001 	 * sys_bpf->prog_test_run->bpf_prog->bpf_sys_close
6002 	 */
6003 	return close_fd(fd);
6004 }
6005 
6006 static const struct bpf_func_proto bpf_sys_close_proto = {
6007 	.func		= bpf_sys_close,
6008 	.gpl_only	= false,
6009 	.ret_type	= RET_INTEGER,
6010 	.arg1_type	= ARG_ANYTHING,
6011 };
6012 
6013 BPF_CALL_4(bpf_kallsyms_lookup_name, const char *, name, int, name_sz, int, flags, u64 *, res)
6014 {
6015 	*res = 0;
6016 	if (flags)
6017 		return -EINVAL;
6018 
6019 	if (name_sz <= 1 || name[name_sz - 1])
6020 		return -EINVAL;
6021 
6022 	if (!bpf_dump_raw_ok(current_cred()))
6023 		return -EPERM;
6024 
6025 	*res = kallsyms_lookup_name(name);
6026 	return *res ? 0 : -ENOENT;
6027 }
6028 
6029 static const struct bpf_func_proto bpf_kallsyms_lookup_name_proto = {
6030 	.func		= bpf_kallsyms_lookup_name,
6031 	.gpl_only	= false,
6032 	.ret_type	= RET_INTEGER,
6033 	.arg1_type	= ARG_PTR_TO_MEM,
6034 	.arg2_type	= ARG_CONST_SIZE_OR_ZERO,
6035 	.arg3_type	= ARG_ANYTHING,
6036 	.arg4_type	= ARG_PTR_TO_FIXED_SIZE_MEM | MEM_UNINIT | MEM_WRITE | MEM_ALIGNED,
6037 	.arg4_size	= sizeof(u64),
6038 };
6039 
6040 static const struct bpf_func_proto *
6041 syscall_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
6042 {
6043 	switch (func_id) {
6044 	case BPF_FUNC_sys_bpf:
6045 		return !bpf_token_capable(prog->aux->token, CAP_PERFMON)
6046 		       ? NULL : &bpf_sys_bpf_proto;
6047 	case BPF_FUNC_btf_find_by_name_kind:
6048 		return &bpf_btf_find_by_name_kind_proto;
6049 	case BPF_FUNC_sys_close:
6050 		return &bpf_sys_close_proto;
6051 	case BPF_FUNC_kallsyms_lookup_name:
6052 		return &bpf_kallsyms_lookup_name_proto;
6053 	default:
6054 		return tracing_prog_func_proto(func_id, prog);
6055 	}
6056 }
6057 
6058 const struct bpf_verifier_ops bpf_syscall_verifier_ops = {
6059 	.get_func_proto  = syscall_prog_func_proto,
6060 	.is_valid_access = syscall_prog_is_valid_access,
6061 };
6062 
6063 const struct bpf_prog_ops bpf_syscall_prog_ops = {
6064 	.test_run = bpf_prog_test_run_syscall,
6065 };
6066 
6067 #ifdef CONFIG_SYSCTL
6068 static int bpf_stats_handler(const struct ctl_table *table, int write,
6069 			     void *buffer, size_t *lenp, loff_t *ppos)
6070 {
6071 	struct static_key *key = (struct static_key *)table->data;
6072 	static int saved_val;
6073 	int val, ret;
6074 	struct ctl_table tmp = {
6075 		.data   = &val,
6076 		.maxlen = sizeof(val),
6077 		.mode   = table->mode,
6078 		.extra1 = SYSCTL_ZERO,
6079 		.extra2 = SYSCTL_ONE,
6080 	};
6081 
6082 	if (write && !capable(CAP_SYS_ADMIN))
6083 		return -EPERM;
6084 
6085 	mutex_lock(&bpf_stats_enabled_mutex);
6086 	val = saved_val;
6087 	ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
6088 	if (write && !ret && val != saved_val) {
6089 		if (val)
6090 			static_key_slow_inc(key);
6091 		else
6092 			static_key_slow_dec(key);
6093 		saved_val = val;
6094 	}
6095 	mutex_unlock(&bpf_stats_enabled_mutex);
6096 	return ret;
6097 }
6098 
6099 void __weak unpriv_ebpf_notify(int new_state)
6100 {
6101 }
6102 
6103 static int bpf_unpriv_handler(const struct ctl_table *table, int write,
6104 			      void *buffer, size_t *lenp, loff_t *ppos)
6105 {
6106 	int ret, unpriv_enable = *(int *)table->data;
6107 	bool locked_state = unpriv_enable == 1;
6108 	struct ctl_table tmp = *table;
6109 
6110 	if (write && !capable(CAP_SYS_ADMIN))
6111 		return -EPERM;
6112 
6113 	tmp.data = &unpriv_enable;
6114 	ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
6115 	if (write && !ret) {
6116 		if (locked_state && unpriv_enable != 1)
6117 			return -EPERM;
6118 		*(int *)table->data = unpriv_enable;
6119 	}
6120 
6121 	if (write)
6122 		unpriv_ebpf_notify(unpriv_enable);
6123 
6124 	return ret;
6125 }
6126 
6127 static struct ctl_table bpf_syscall_table[] = {
6128 	{
6129 		.procname	= "unprivileged_bpf_disabled",
6130 		.data		= &sysctl_unprivileged_bpf_disabled,
6131 		.maxlen		= sizeof(sysctl_unprivileged_bpf_disabled),
6132 		.mode		= 0644,
6133 		.proc_handler	= bpf_unpriv_handler,
6134 		.extra1		= SYSCTL_ZERO,
6135 		.extra2		= SYSCTL_TWO,
6136 	},
6137 	{
6138 		.procname	= "bpf_stats_enabled",
6139 		.data		= &bpf_stats_enabled_key.key,
6140 		.mode		= 0644,
6141 		.proc_handler	= bpf_stats_handler,
6142 	},
6143 };
6144 
6145 static int __init bpf_syscall_sysctl_init(void)
6146 {
6147 	register_sysctl_init("kernel", bpf_syscall_table);
6148 	return 0;
6149 }
6150 late_initcall(bpf_syscall_sysctl_init);
6151 #endif /* CONFIG_SYSCTL */
6152