1 // SPDX-License-Identifier: GPL-2.0-only
2 /* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
3 */
4 #include <crypto/sha2.h>
5 #include <linux/bpf.h>
6 #include <linux/bpf-cgroup.h>
7 #include <linux/bpf_trace.h>
8 #include <linux/bpf_lirc.h>
9 #include <linux/bpf_verifier.h>
10 #include <linux/bsearch.h>
11 #include <linux/btf.h>
12 #include <linux/hex.h>
13 #include <linux/syscalls.h>
14 #include <linux/slab.h>
15 #include <linux/sched/signal.h>
16 #include <linux/vmalloc.h>
17 #include <linux/mmzone.h>
18 #include <linux/anon_inodes.h>
19 #include <linux/fdtable.h>
20 #include <linux/file.h>
21 #include <linux/fs.h>
22 #include <linux/license.h>
23 #include <linux/filter.h>
24 #include <linux/kernel.h>
25 #include <linux/idr.h>
26 #include <linux/cred.h>
27 #include <linux/timekeeping.h>
28 #include <linux/ctype.h>
29 #include <linux/nospec.h>
30 #include <linux/audit.h>
31 #include <uapi/linux/btf.h>
32 #include <linux/pgtable.h>
33 #include <linux/bpf_lsm.h>
34 #include <linux/poll.h>
35 #include <linux/sort.h>
36 #include <linux/bpf-netns.h>
37 #include <linux/rcupdate_trace.h>
38 #include <linux/memcontrol.h>
39 #include <linux/trace_events.h>
40 #include <linux/tracepoint.h>
41 #include <linux/overflow.h>
42 #include <linux/cookie.h>
43 #include <linux/verification.h>
44
45 #include <net/netfilter/nf_bpf_link.h>
46 #include <net/netkit.h>
47 #include <net/tcx.h>
48
49 #define IS_FD_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || \
50 (map)->map_type == BPF_MAP_TYPE_CGROUP_ARRAY || \
51 (map)->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS)
52 #define IS_FD_PROG_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PROG_ARRAY)
53 #define IS_FD_HASH(map) ((map)->map_type == BPF_MAP_TYPE_HASH_OF_MAPS)
54 #define IS_FD_MAP(map) (IS_FD_ARRAY(map) || IS_FD_PROG_ARRAY(map) || \
55 IS_FD_HASH(map))
56
57 #define BPF_OBJ_FLAG_MASK (BPF_F_RDONLY | BPF_F_WRONLY)
58
59 DEFINE_PER_CPU(int, bpf_prog_active);
60 DEFINE_COOKIE(bpf_map_cookie);
61 static DEFINE_IDR(prog_idr);
62 static DEFINE_SPINLOCK(prog_idr_lock);
63 static DEFINE_IDR(map_idr);
64 static DEFINE_SPINLOCK(map_idr_lock);
65 static DEFINE_IDR(link_idr);
66 static DEFINE_SPINLOCK(link_idr_lock);
67
68 int sysctl_unprivileged_bpf_disabled __read_mostly =
69 IS_BUILTIN(CONFIG_BPF_UNPRIV_DEFAULT_OFF) ? 2 : 0;
70
71 static const struct bpf_map_ops * const bpf_map_types[] = {
72 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type)
73 #define BPF_MAP_TYPE(_id, _ops) \
74 [_id] = &_ops,
75 #define BPF_LINK_TYPE(_id, _name)
76 #include <linux/bpf_types.h>
77 #undef BPF_PROG_TYPE
78 #undef BPF_MAP_TYPE
79 #undef BPF_LINK_TYPE
80 };
81
82 /*
83 * If we're handed a bigger struct than we know of, ensure all the unknown bits
84 * are 0 - i.e. new user-space does not rely on any kernel feature extensions
85 * we don't know about yet.
86 *
87 * There is a ToCToU between this function call and the following
88 * copy_from_user() call. However, this is not a concern since this function is
89 * meant to be a future-proofing of bits.
90 */
bpf_check_uarg_tail_zero(bpfptr_t uaddr,size_t expected_size,size_t actual_size)91 int bpf_check_uarg_tail_zero(bpfptr_t uaddr,
92 size_t expected_size,
93 size_t actual_size)
94 {
95 int res;
96
97 if (unlikely(actual_size > PAGE_SIZE)) /* silly large */
98 return -E2BIG;
99
100 if (actual_size <= expected_size)
101 return 0;
102
103 if (uaddr.is_kernel)
104 res = memchr_inv(uaddr.kernel + expected_size, 0,
105 actual_size - expected_size) == NULL;
106 else
107 res = check_zeroed_user(uaddr.user + expected_size,
108 actual_size - expected_size);
109 if (res < 0)
110 return res;
111 return res ? 0 : -E2BIG;
112 }
113
114 const struct bpf_map_ops bpf_map_offload_ops = {
115 .map_meta_equal = bpf_map_meta_equal,
116 .map_alloc = bpf_map_offload_map_alloc,
117 .map_free = bpf_map_offload_map_free,
118 .map_check_btf = map_check_no_btf,
119 .map_mem_usage = bpf_map_offload_map_mem_usage,
120 };
121
bpf_map_write_active_inc(struct bpf_map * map)122 static void bpf_map_write_active_inc(struct bpf_map *map)
123 {
124 atomic64_inc(&map->writecnt);
125 }
126
bpf_map_write_active_dec(struct bpf_map * map)127 static void bpf_map_write_active_dec(struct bpf_map *map)
128 {
129 atomic64_dec(&map->writecnt);
130 }
131
bpf_map_write_active(const struct bpf_map * map)132 bool bpf_map_write_active(const struct bpf_map *map)
133 {
134 return atomic64_read(&map->writecnt) != 0;
135 }
136
bpf_map_value_size(const struct bpf_map * map,u64 flags)137 static u32 bpf_map_value_size(const struct bpf_map *map, u64 flags)
138 {
139 if (flags & (BPF_F_CPU | BPF_F_ALL_CPUS))
140 return map->value_size;
141 else if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
142 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH ||
143 map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY ||
144 map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE)
145 return round_up(map->value_size, 8) * num_possible_cpus();
146 else if (IS_FD_MAP(map))
147 return sizeof(u32);
148 else
149 return map->value_size;
150 }
151
maybe_wait_bpf_programs(struct bpf_map * map)152 static void maybe_wait_bpf_programs(struct bpf_map *map)
153 {
154 /* Wait for any running non-sleepable BPF programs to complete so that
155 * userspace, when we return to it, knows that all non-sleepable
156 * programs that could be running use the new map value. For sleepable
157 * BPF programs, synchronize_rcu_tasks_trace() should be used to wait
158 * for the completions of these programs, but considering the waiting
159 * time can be very long and userspace may think it will hang forever,
160 * so don't handle sleepable BPF programs now.
161 */
162 if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS ||
163 map->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS)
164 synchronize_rcu_expedited();
165 }
166
unpin_uptr_kaddr(void * kaddr)167 static void unpin_uptr_kaddr(void *kaddr)
168 {
169 if (kaddr)
170 unpin_user_page(virt_to_page(kaddr));
171 }
172
__bpf_obj_unpin_uptrs(struct btf_record * rec,u32 cnt,void * obj)173 static void __bpf_obj_unpin_uptrs(struct btf_record *rec, u32 cnt, void *obj)
174 {
175 const struct btf_field *field;
176 void **uptr_addr;
177 int i;
178
179 for (i = 0, field = rec->fields; i < cnt; i++, field++) {
180 if (field->type != BPF_UPTR)
181 continue;
182
183 uptr_addr = obj + field->offset;
184 unpin_uptr_kaddr(*uptr_addr);
185 }
186 }
187
bpf_obj_unpin_uptrs(struct btf_record * rec,void * obj)188 static void bpf_obj_unpin_uptrs(struct btf_record *rec, void *obj)
189 {
190 if (!btf_record_has_field(rec, BPF_UPTR))
191 return;
192
193 __bpf_obj_unpin_uptrs(rec, rec->cnt, obj);
194 }
195
bpf_obj_pin_uptrs(struct btf_record * rec,void * obj)196 static int bpf_obj_pin_uptrs(struct btf_record *rec, void *obj)
197 {
198 const struct btf_field *field;
199 const struct btf_type *t;
200 unsigned long start, end;
201 struct page *page;
202 void **uptr_addr;
203 int i, err;
204
205 if (!btf_record_has_field(rec, BPF_UPTR))
206 return 0;
207
208 for (i = 0, field = rec->fields; i < rec->cnt; i++, field++) {
209 if (field->type != BPF_UPTR)
210 continue;
211
212 uptr_addr = obj + field->offset;
213 start = *(unsigned long *)uptr_addr;
214 if (!start)
215 continue;
216
217 t = btf_type_by_id(field->kptr.btf, field->kptr.btf_id);
218 /* t->size was checked for zero before */
219 if (check_add_overflow(start, t->size - 1, &end)) {
220 err = -EFAULT;
221 goto unpin_all;
222 }
223
224 /* The uptr's struct cannot span across two pages */
225 if ((start & PAGE_MASK) != (end & PAGE_MASK)) {
226 err = -EOPNOTSUPP;
227 goto unpin_all;
228 }
229
230 err = pin_user_pages_fast(start, 1, FOLL_LONGTERM | FOLL_WRITE, &page);
231 if (err != 1)
232 goto unpin_all;
233
234 if (PageHighMem(page)) {
235 err = -EOPNOTSUPP;
236 unpin_user_page(page);
237 goto unpin_all;
238 }
239
240 *uptr_addr = page_address(page) + offset_in_page(start);
241 }
242
243 return 0;
244
245 unpin_all:
246 __bpf_obj_unpin_uptrs(rec, i, obj);
247 return err;
248 }
249
bpf_map_update_value(struct bpf_map * map,struct file * map_file,void * key,void * value,__u64 flags)250 static int bpf_map_update_value(struct bpf_map *map, struct file *map_file,
251 void *key, void *value, __u64 flags)
252 {
253 int err;
254
255 /* Need to create a kthread, thus must support schedule */
256 if (bpf_map_is_offloaded(map)) {
257 return bpf_map_offload_update_elem(map, key, value, flags);
258 } else if (map->map_type == BPF_MAP_TYPE_CPUMAP ||
259 map->map_type == BPF_MAP_TYPE_ARENA ||
260 map->map_type == BPF_MAP_TYPE_STRUCT_OPS) {
261 return map->ops->map_update_elem(map, key, value, flags);
262 } else if (map->map_type == BPF_MAP_TYPE_SOCKHASH ||
263 map->map_type == BPF_MAP_TYPE_SOCKMAP) {
264 return sock_map_update_elem_sys(map, key, value, flags);
265 } else if (IS_FD_PROG_ARRAY(map)) {
266 return bpf_fd_array_map_update_elem(map, map_file, key, value,
267 flags);
268 }
269
270 bpf_disable_instrumentation();
271 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
272 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
273 err = bpf_percpu_hash_update(map, key, value, flags);
274 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) {
275 err = bpf_percpu_array_update(map, key, value, flags);
276 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) {
277 err = bpf_percpu_cgroup_storage_update(map, key, value,
278 flags);
279 } else if (IS_FD_ARRAY(map)) {
280 err = bpf_fd_array_map_update_elem(map, map_file, key, value,
281 flags);
282 } else if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) {
283 err = bpf_fd_htab_map_update_elem(map, map_file, key, value,
284 flags);
285 } else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) {
286 /* rcu_read_lock() is not needed */
287 err = bpf_fd_reuseport_array_update_elem(map, key, value,
288 flags);
289 } else if (map->map_type == BPF_MAP_TYPE_QUEUE ||
290 map->map_type == BPF_MAP_TYPE_STACK ||
291 map->map_type == BPF_MAP_TYPE_BLOOM_FILTER) {
292 err = map->ops->map_push_elem(map, value, flags);
293 } else {
294 err = bpf_obj_pin_uptrs(map->record, value);
295 if (!err) {
296 rcu_read_lock();
297 err = map->ops->map_update_elem(map, key, value, flags);
298 rcu_read_unlock();
299 if (err)
300 bpf_obj_unpin_uptrs(map->record, value);
301 }
302 }
303 bpf_enable_instrumentation();
304
305 return err;
306 }
307
bpf_map_copy_value(struct bpf_map * map,void * key,void * value,__u64 flags)308 static int bpf_map_copy_value(struct bpf_map *map, void *key, void *value,
309 __u64 flags)
310 {
311 void *ptr;
312 int err;
313
314 if (bpf_map_is_offloaded(map))
315 return bpf_map_offload_lookup_elem(map, key, value);
316
317 bpf_disable_instrumentation();
318 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
319 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
320 err = bpf_percpu_hash_copy(map, key, value, flags);
321 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) {
322 err = bpf_percpu_array_copy(map, key, value, flags);
323 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) {
324 err = bpf_percpu_cgroup_storage_copy(map, key, value, flags);
325 } else if (map->map_type == BPF_MAP_TYPE_STACK_TRACE) {
326 err = bpf_stackmap_extract(map, key, value, false);
327 } else if (IS_FD_ARRAY(map) || IS_FD_PROG_ARRAY(map)) {
328 err = bpf_fd_array_map_lookup_elem(map, key, value);
329 } else if (IS_FD_HASH(map)) {
330 err = bpf_fd_htab_map_lookup_elem(map, key, value);
331 } else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) {
332 err = bpf_fd_reuseport_array_lookup_elem(map, key, value);
333 } else if (map->map_type == BPF_MAP_TYPE_QUEUE ||
334 map->map_type == BPF_MAP_TYPE_STACK ||
335 map->map_type == BPF_MAP_TYPE_BLOOM_FILTER) {
336 err = map->ops->map_peek_elem(map, value);
337 } else if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS) {
338 /* struct_ops map requires directly updating "value" */
339 err = bpf_struct_ops_map_sys_lookup_elem(map, key, value);
340 } else {
341 rcu_read_lock();
342 if (map->ops->map_lookup_elem_sys_only)
343 ptr = map->ops->map_lookup_elem_sys_only(map, key);
344 else
345 ptr = map->ops->map_lookup_elem(map, key);
346 if (IS_ERR(ptr)) {
347 err = PTR_ERR(ptr);
348 } else if (!ptr) {
349 err = -ENOENT;
350 } else {
351 err = 0;
352 if (flags & BPF_F_LOCK)
353 /* lock 'ptr' and copy everything but lock */
354 copy_map_value_locked(map, value, ptr, true);
355 else
356 copy_map_value(map, value, ptr);
357 /* mask lock and timer, since value wasn't zero inited */
358 check_and_init_map_value(map, value);
359 }
360 rcu_read_unlock();
361 }
362
363 bpf_enable_instrumentation();
364
365 return err;
366 }
367
368 /* Please, do not use this function outside from the map creation path
369 * (e.g. in map update path) without taking care of setting the active
370 * memory cgroup (see at bpf_map_kmalloc_node() for example).
371 */
__bpf_map_area_alloc(u64 size,int numa_node,bool mmapable)372 static void *__bpf_map_area_alloc(u64 size, int numa_node, bool mmapable)
373 {
374 /* We really just want to fail instead of triggering OOM killer
375 * under memory pressure, therefore we set __GFP_NORETRY to kmalloc,
376 * which is used for lower order allocation requests.
377 *
378 * It has been observed that higher order allocation requests done by
379 * vmalloc with __GFP_NORETRY being set might fail due to not trying
380 * to reclaim memory from the page cache, thus we set
381 * __GFP_RETRY_MAYFAIL to avoid such situations.
382 */
383
384 gfp_t gfp = bpf_memcg_flags(__GFP_NOWARN | __GFP_ZERO);
385 unsigned int flags = 0;
386 unsigned long align = 1;
387 void *area;
388
389 if (size >= SIZE_MAX)
390 return NULL;
391
392 /* kmalloc()'ed memory can't be mmap()'ed */
393 if (mmapable) {
394 BUG_ON(!PAGE_ALIGNED(size));
395 align = SHMLBA;
396 flags = VM_USERMAP;
397 } else if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) {
398 area = kmalloc_node(size, gfp | GFP_USER | __GFP_NORETRY,
399 numa_node);
400 if (area != NULL)
401 return area;
402 }
403
404 return __vmalloc_node_range(size, align, VMALLOC_START, VMALLOC_END,
405 gfp | GFP_KERNEL | __GFP_RETRY_MAYFAIL, PAGE_KERNEL,
406 flags, numa_node, __builtin_return_address(0));
407 }
408
bpf_map_area_alloc(u64 size,int numa_node)409 void *bpf_map_area_alloc(u64 size, int numa_node)
410 {
411 return __bpf_map_area_alloc(size, numa_node, false);
412 }
413
bpf_map_area_mmapable_alloc(u64 size,int numa_node)414 void *bpf_map_area_mmapable_alloc(u64 size, int numa_node)
415 {
416 return __bpf_map_area_alloc(size, numa_node, true);
417 }
418
bpf_map_area_free(void * area)419 void bpf_map_area_free(void *area)
420 {
421 kvfree(area);
422 }
423
bpf_map_flags_retain_permanent(u32 flags)424 static u32 bpf_map_flags_retain_permanent(u32 flags)
425 {
426 /* Some map creation flags are not tied to the map object but
427 * rather to the map fd instead, so they have no meaning upon
428 * map object inspection since multiple file descriptors with
429 * different (access) properties can exist here. Thus, given
430 * this has zero meaning for the map itself, lets clear these
431 * from here.
432 */
433 return flags & ~(BPF_F_RDONLY | BPF_F_WRONLY);
434 }
435
bpf_map_init_from_attr(struct bpf_map * map,union bpf_attr * attr)436 void bpf_map_init_from_attr(struct bpf_map *map, union bpf_attr *attr)
437 {
438 map->map_type = attr->map_type;
439 map->key_size = attr->key_size;
440 map->value_size = attr->value_size;
441 map->max_entries = attr->max_entries;
442 map->map_flags = bpf_map_flags_retain_permanent(attr->map_flags);
443 map->numa_node = bpf_map_attr_numa_node(attr);
444 map->map_extra = attr->map_extra;
445 }
446
bpf_map_alloc_id(struct bpf_map * map)447 static int bpf_map_alloc_id(struct bpf_map *map)
448 {
449 int id;
450
451 idr_preload(GFP_KERNEL);
452 spin_lock_bh(&map_idr_lock);
453 id = idr_alloc_cyclic(&map_idr, map, 1, INT_MAX, GFP_ATOMIC);
454 if (id > 0)
455 map->id = id;
456 spin_unlock_bh(&map_idr_lock);
457 idr_preload_end();
458
459 if (WARN_ON_ONCE(!id))
460 return -ENOSPC;
461
462 return id > 0 ? 0 : id;
463 }
464
bpf_map_free_id(struct bpf_map * map)465 void bpf_map_free_id(struct bpf_map *map)
466 {
467 unsigned long flags;
468
469 /* Offloaded maps are removed from the IDR store when their device
470 * disappears - even if someone holds an fd to them they are unusable,
471 * the memory is gone, all ops will fail; they are simply waiting for
472 * refcnt to drop to be freed.
473 */
474 if (!map->id)
475 return;
476
477 spin_lock_irqsave(&map_idr_lock, flags);
478
479 idr_remove(&map_idr, map->id);
480 map->id = 0;
481
482 spin_unlock_irqrestore(&map_idr_lock, flags);
483 }
484
485 #ifdef CONFIG_MEMCG
bpf_map_save_memcg(struct bpf_map * map)486 static void bpf_map_save_memcg(struct bpf_map *map)
487 {
488 /* Currently if a map is created by a process belonging to the root
489 * memory cgroup, get_obj_cgroup_from_current() will return NULL.
490 * So we have to check map->objcg for being NULL each time it's
491 * being used.
492 */
493 if (memcg_bpf_enabled())
494 map->objcg = get_obj_cgroup_from_current();
495 }
496
bpf_map_release_memcg(struct bpf_map * map)497 static void bpf_map_release_memcg(struct bpf_map *map)
498 {
499 if (map->objcg)
500 obj_cgroup_put(map->objcg);
501 }
502
bpf_map_get_memcg(const struct bpf_map * map)503 static struct mem_cgroup *bpf_map_get_memcg(const struct bpf_map *map)
504 {
505 if (map->objcg)
506 return get_mem_cgroup_from_objcg(map->objcg);
507
508 return root_mem_cgroup;
509 }
510
bpf_map_memcg_enter(const struct bpf_map * map,struct mem_cgroup ** old_memcg,struct mem_cgroup ** new_memcg)511 void bpf_map_memcg_enter(const struct bpf_map *map, struct mem_cgroup **old_memcg,
512 struct mem_cgroup **new_memcg)
513 {
514 *new_memcg = bpf_map_get_memcg(map);
515 *old_memcg = set_active_memcg(*new_memcg);
516 }
517
bpf_map_memcg_exit(struct mem_cgroup * old_memcg,struct mem_cgroup * new_memcg)518 void bpf_map_memcg_exit(struct mem_cgroup *old_memcg,
519 struct mem_cgroup *new_memcg)
520 {
521 set_active_memcg(old_memcg);
522 mem_cgroup_put(new_memcg);
523 }
524
bpf_map_kmalloc_node(const struct bpf_map * map,size_t size,gfp_t flags,int node)525 void *bpf_map_kmalloc_node(const struct bpf_map *map, size_t size, gfp_t flags,
526 int node)
527 {
528 struct mem_cgroup *memcg, *old_memcg;
529 void *ptr;
530
531 bpf_map_memcg_enter(map, &old_memcg, &memcg);
532 ptr = kmalloc_node(size, flags | __GFP_ACCOUNT, node);
533 bpf_map_memcg_exit(old_memcg, memcg);
534
535 return ptr;
536 }
537
bpf_map_kmalloc_nolock(const struct bpf_map * map,size_t size,gfp_t flags,int node)538 void *bpf_map_kmalloc_nolock(const struct bpf_map *map, size_t size, gfp_t flags,
539 int node)
540 {
541 struct mem_cgroup *memcg, *old_memcg;
542 void *ptr;
543
544 bpf_map_memcg_enter(map, &old_memcg, &memcg);
545 ptr = kmalloc_nolock(size, flags | __GFP_ACCOUNT, node);
546 bpf_map_memcg_exit(old_memcg, memcg);
547
548 return ptr;
549 }
550
bpf_map_kzalloc(const struct bpf_map * map,size_t size,gfp_t flags)551 void *bpf_map_kzalloc(const struct bpf_map *map, size_t size, gfp_t flags)
552 {
553 struct mem_cgroup *memcg, *old_memcg;
554 void *ptr;
555
556 bpf_map_memcg_enter(map, &old_memcg, &memcg);
557 ptr = kzalloc(size, flags | __GFP_ACCOUNT);
558 bpf_map_memcg_exit(old_memcg, memcg);
559
560 return ptr;
561 }
562
bpf_map_kvcalloc(struct bpf_map * map,size_t n,size_t size,gfp_t flags)563 void *bpf_map_kvcalloc(struct bpf_map *map, size_t n, size_t size,
564 gfp_t flags)
565 {
566 struct mem_cgroup *memcg, *old_memcg;
567 void *ptr;
568
569 bpf_map_memcg_enter(map, &old_memcg, &memcg);
570 ptr = kvcalloc(n, size, flags | __GFP_ACCOUNT);
571 bpf_map_memcg_exit(old_memcg, memcg);
572
573 return ptr;
574 }
575
bpf_map_alloc_percpu(const struct bpf_map * map,size_t size,size_t align,gfp_t flags)576 void __percpu *bpf_map_alloc_percpu(const struct bpf_map *map, size_t size,
577 size_t align, gfp_t flags)
578 {
579 struct mem_cgroup *memcg, *old_memcg;
580 void __percpu *ptr;
581
582 bpf_map_memcg_enter(map, &old_memcg, &memcg);
583 ptr = __alloc_percpu_gfp(size, align, flags | __GFP_ACCOUNT);
584 bpf_map_memcg_exit(old_memcg, memcg);
585
586 return ptr;
587 }
588
589 #else
bpf_map_save_memcg(struct bpf_map * map)590 static void bpf_map_save_memcg(struct bpf_map *map)
591 {
592 }
593
bpf_map_release_memcg(struct bpf_map * map)594 static void bpf_map_release_memcg(struct bpf_map *map)
595 {
596 }
597 #endif
598
can_alloc_pages(void)599 static bool can_alloc_pages(void)
600 {
601 return preempt_count() == 0 && !irqs_disabled() &&
602 !IS_ENABLED(CONFIG_PREEMPT_RT);
603 }
604
__bpf_alloc_page(int nid)605 static struct page *__bpf_alloc_page(int nid)
606 {
607 if (!can_alloc_pages())
608 return alloc_pages_nolock(__GFP_ACCOUNT, nid, 0);
609
610 return alloc_pages_node(nid,
611 GFP_KERNEL | __GFP_ZERO | __GFP_ACCOUNT
612 | __GFP_NOWARN,
613 0);
614 }
615
bpf_map_alloc_pages(const struct bpf_map * map,int nid,unsigned long nr_pages,struct page ** pages)616 int bpf_map_alloc_pages(const struct bpf_map *map, int nid,
617 unsigned long nr_pages, struct page **pages)
618 {
619 unsigned long i, j;
620 struct page *pg;
621 int ret = 0;
622
623 for (i = 0; i < nr_pages; i++) {
624 pg = __bpf_alloc_page(nid);
625
626 if (pg) {
627 pages[i] = pg;
628 continue;
629 }
630 for (j = 0; j < i; j++)
631 free_pages_nolock(pages[j], 0);
632 ret = -ENOMEM;
633 break;
634 }
635
636 return ret;
637 }
638
639
btf_field_cmp(const void * a,const void * b)640 static int btf_field_cmp(const void *a, const void *b)
641 {
642 const struct btf_field *f1 = a, *f2 = b;
643
644 if (f1->offset < f2->offset)
645 return -1;
646 else if (f1->offset > f2->offset)
647 return 1;
648 return 0;
649 }
650
btf_record_find(const struct btf_record * rec,u32 offset,u32 field_mask)651 struct btf_field *btf_record_find(const struct btf_record *rec, u32 offset,
652 u32 field_mask)
653 {
654 struct btf_field *field;
655
656 if (IS_ERR_OR_NULL(rec) || !(rec->field_mask & field_mask))
657 return NULL;
658 field = bsearch(&offset, rec->fields, rec->cnt, sizeof(rec->fields[0]), btf_field_cmp);
659 if (!field || !(field->type & field_mask))
660 return NULL;
661 return field;
662 }
663
btf_record_free(struct btf_record * rec)664 void btf_record_free(struct btf_record *rec)
665 {
666 int i;
667
668 if (IS_ERR_OR_NULL(rec))
669 return;
670 for (i = 0; i < rec->cnt; i++) {
671 switch (rec->fields[i].type) {
672 case BPF_KPTR_UNREF:
673 case BPF_KPTR_REF:
674 case BPF_KPTR_PERCPU:
675 case BPF_UPTR:
676 if (rec->fields[i].kptr.module)
677 module_put(rec->fields[i].kptr.module);
678 if (btf_is_kernel(rec->fields[i].kptr.btf))
679 btf_put(rec->fields[i].kptr.btf);
680 break;
681 case BPF_LIST_HEAD:
682 case BPF_LIST_NODE:
683 case BPF_RB_ROOT:
684 case BPF_RB_NODE:
685 case BPF_SPIN_LOCK:
686 case BPF_RES_SPIN_LOCK:
687 case BPF_TIMER:
688 case BPF_REFCOUNT:
689 case BPF_WORKQUEUE:
690 case BPF_TASK_WORK:
691 /* Nothing to release */
692 break;
693 default:
694 WARN_ON_ONCE(1);
695 continue;
696 }
697 }
698 kfree(rec);
699 }
700
bpf_map_free_record(struct bpf_map * map)701 void bpf_map_free_record(struct bpf_map *map)
702 {
703 btf_record_free(map->record);
704 map->record = NULL;
705 }
706
btf_record_dup(const struct btf_record * rec)707 struct btf_record *btf_record_dup(const struct btf_record *rec)
708 {
709 const struct btf_field *fields;
710 struct btf_record *new_rec;
711 int ret, size, i;
712
713 if (IS_ERR_OR_NULL(rec))
714 return NULL;
715 size = struct_size(rec, fields, rec->cnt);
716 new_rec = kmemdup(rec, size, GFP_KERNEL | __GFP_NOWARN);
717 if (!new_rec)
718 return ERR_PTR(-ENOMEM);
719 /* Do a deep copy of the btf_record */
720 fields = rec->fields;
721 new_rec->cnt = 0;
722 for (i = 0; i < rec->cnt; i++) {
723 switch (fields[i].type) {
724 case BPF_KPTR_UNREF:
725 case BPF_KPTR_REF:
726 case BPF_KPTR_PERCPU:
727 case BPF_UPTR:
728 if (btf_is_kernel(fields[i].kptr.btf))
729 btf_get(fields[i].kptr.btf);
730 if (fields[i].kptr.module && !try_module_get(fields[i].kptr.module)) {
731 ret = -ENXIO;
732 goto free;
733 }
734 break;
735 case BPF_LIST_HEAD:
736 case BPF_LIST_NODE:
737 case BPF_RB_ROOT:
738 case BPF_RB_NODE:
739 case BPF_SPIN_LOCK:
740 case BPF_RES_SPIN_LOCK:
741 case BPF_TIMER:
742 case BPF_REFCOUNT:
743 case BPF_WORKQUEUE:
744 case BPF_TASK_WORK:
745 /* Nothing to acquire */
746 break;
747 default:
748 ret = -EFAULT;
749 WARN_ON_ONCE(1);
750 goto free;
751 }
752 new_rec->cnt++;
753 }
754 return new_rec;
755 free:
756 btf_record_free(new_rec);
757 return ERR_PTR(ret);
758 }
759
btf_record_equal(const struct btf_record * rec_a,const struct btf_record * rec_b)760 bool btf_record_equal(const struct btf_record *rec_a, const struct btf_record *rec_b)
761 {
762 bool a_has_fields = !IS_ERR_OR_NULL(rec_a), b_has_fields = !IS_ERR_OR_NULL(rec_b);
763 int size;
764
765 if (!a_has_fields && !b_has_fields)
766 return true;
767 if (a_has_fields != b_has_fields)
768 return false;
769 if (rec_a->cnt != rec_b->cnt)
770 return false;
771 size = struct_size(rec_a, fields, rec_a->cnt);
772 /* btf_parse_fields uses kzalloc to allocate a btf_record, so unused
773 * members are zeroed out. So memcmp is safe to do without worrying
774 * about padding/unused fields.
775 *
776 * While spin_lock, timer, and kptr have no relation to map BTF,
777 * list_head metadata is specific to map BTF, the btf and value_rec
778 * members in particular. btf is the map BTF, while value_rec points to
779 * btf_record in that map BTF.
780 *
781 * So while by default, we don't rely on the map BTF (which the records
782 * were parsed from) matching for both records, which is not backwards
783 * compatible, in case list_head is part of it, we implicitly rely on
784 * that by way of depending on memcmp succeeding for it.
785 */
786 return !memcmp(rec_a, rec_b, size);
787 }
788
bpf_obj_free_timer(const struct btf_record * rec,void * obj)789 void bpf_obj_free_timer(const struct btf_record *rec, void *obj)
790 {
791 if (WARN_ON_ONCE(!btf_record_has_field(rec, BPF_TIMER)))
792 return;
793 bpf_timer_cancel_and_free(obj + rec->timer_off);
794 }
795
bpf_obj_free_workqueue(const struct btf_record * rec,void * obj)796 void bpf_obj_free_workqueue(const struct btf_record *rec, void *obj)
797 {
798 if (WARN_ON_ONCE(!btf_record_has_field(rec, BPF_WORKQUEUE)))
799 return;
800 bpf_wq_cancel_and_free(obj + rec->wq_off);
801 }
802
bpf_obj_free_task_work(const struct btf_record * rec,void * obj)803 void bpf_obj_free_task_work(const struct btf_record *rec, void *obj)
804 {
805 if (WARN_ON_ONCE(!btf_record_has_field(rec, BPF_TASK_WORK)))
806 return;
807 bpf_task_work_cancel_and_free(obj + rec->task_work_off);
808 }
809
bpf_obj_free_fields(const struct btf_record * rec,void * obj)810 void bpf_obj_free_fields(const struct btf_record *rec, void *obj)
811 {
812 const struct btf_field *fields;
813 int i;
814
815 if (IS_ERR_OR_NULL(rec))
816 return;
817 fields = rec->fields;
818 for (i = 0; i < rec->cnt; i++) {
819 struct btf_struct_meta *pointee_struct_meta;
820 const struct btf_field *field = &fields[i];
821 void *field_ptr = obj + field->offset;
822 void *xchgd_field;
823
824 switch (fields[i].type) {
825 case BPF_SPIN_LOCK:
826 case BPF_RES_SPIN_LOCK:
827 break;
828 case BPF_TIMER:
829 bpf_timer_cancel_and_free(field_ptr);
830 break;
831 case BPF_WORKQUEUE:
832 bpf_wq_cancel_and_free(field_ptr);
833 break;
834 case BPF_TASK_WORK:
835 bpf_task_work_cancel_and_free(field_ptr);
836 break;
837 case BPF_KPTR_UNREF:
838 WRITE_ONCE(*(u64 *)field_ptr, 0);
839 break;
840 case BPF_KPTR_REF:
841 case BPF_KPTR_PERCPU:
842 xchgd_field = (void *)xchg((unsigned long *)field_ptr, 0);
843 if (!xchgd_field)
844 break;
845
846 if (!btf_is_kernel(field->kptr.btf)) {
847 pointee_struct_meta = btf_find_struct_meta(field->kptr.btf,
848 field->kptr.btf_id);
849 __bpf_obj_drop_impl(xchgd_field, pointee_struct_meta ?
850 pointee_struct_meta->record : NULL,
851 fields[i].type == BPF_KPTR_PERCPU);
852 } else {
853 field->kptr.dtor(xchgd_field);
854 }
855 break;
856 case BPF_UPTR:
857 /* The caller ensured that no one is using the uptr */
858 unpin_uptr_kaddr(*(void **)field_ptr);
859 break;
860 case BPF_LIST_HEAD:
861 if (WARN_ON_ONCE(rec->spin_lock_off < 0))
862 continue;
863 bpf_list_head_free(field, field_ptr, obj + rec->spin_lock_off);
864 break;
865 case BPF_RB_ROOT:
866 if (WARN_ON_ONCE(rec->spin_lock_off < 0))
867 continue;
868 bpf_rb_root_free(field, field_ptr, obj + rec->spin_lock_off);
869 break;
870 case BPF_LIST_NODE:
871 case BPF_RB_NODE:
872 case BPF_REFCOUNT:
873 break;
874 default:
875 WARN_ON_ONCE(1);
876 continue;
877 }
878 }
879 }
880
bpf_map_free(struct bpf_map * map)881 static void bpf_map_free(struct bpf_map *map)
882 {
883 struct btf_record *rec = map->record;
884 struct btf *btf = map->btf;
885
886 /* implementation dependent freeing. Disabling migration to simplify
887 * the free of values or special fields allocated from bpf memory
888 * allocator.
889 */
890 kfree(map->excl_prog_sha);
891 migrate_disable();
892 map->ops->map_free(map);
893 migrate_enable();
894
895 /* Delay freeing of btf_record for maps, as map_free
896 * callback usually needs access to them. It is better to do it here
897 * than require each callback to do the free itself manually.
898 *
899 * Note that the btf_record stashed in map->inner_map_meta->record was
900 * already freed using the map_free callback for map in map case which
901 * eventually calls bpf_map_free_meta, since inner_map_meta is only a
902 * template bpf_map struct used during verification.
903 */
904 btf_record_free(rec);
905 /* Delay freeing of btf for maps, as map_free callback may need
906 * struct_meta info which will be freed with btf_put().
907 */
908 btf_put(btf);
909 }
910
911 /* called from workqueue */
bpf_map_free_deferred(struct work_struct * work)912 static void bpf_map_free_deferred(struct work_struct *work)
913 {
914 struct bpf_map *map = container_of(work, struct bpf_map, work);
915
916 security_bpf_map_free(map);
917 bpf_map_release_memcg(map);
918 bpf_map_owner_free(map);
919 bpf_map_free(map);
920 }
921
bpf_map_put_uref(struct bpf_map * map)922 static void bpf_map_put_uref(struct bpf_map *map)
923 {
924 if (atomic64_dec_and_test(&map->usercnt)) {
925 if (map->ops->map_release_uref)
926 map->ops->map_release_uref(map);
927 }
928 }
929
bpf_map_free_in_work(struct bpf_map * map)930 static void bpf_map_free_in_work(struct bpf_map *map)
931 {
932 INIT_WORK(&map->work, bpf_map_free_deferred);
933 /* Avoid spawning kworkers, since they all might contend
934 * for the same mutex like slab_mutex.
935 */
936 queue_work(system_dfl_wq, &map->work);
937 }
938
bpf_map_free_rcu_gp(struct rcu_head * rcu)939 static void bpf_map_free_rcu_gp(struct rcu_head *rcu)
940 {
941 bpf_map_free_in_work(container_of(rcu, struct bpf_map, rcu));
942 }
943
bpf_map_free_mult_rcu_gp(struct rcu_head * rcu)944 static void bpf_map_free_mult_rcu_gp(struct rcu_head *rcu)
945 {
946 if (rcu_trace_implies_rcu_gp())
947 bpf_map_free_rcu_gp(rcu);
948 else
949 call_rcu(rcu, bpf_map_free_rcu_gp);
950 }
951
952 /* decrement map refcnt and schedule it for freeing via workqueue
953 * (underlying map implementation ops->map_free() might sleep)
954 */
bpf_map_put(struct bpf_map * map)955 void bpf_map_put(struct bpf_map *map)
956 {
957 if (atomic64_dec_and_test(&map->refcnt)) {
958 /* bpf_map_free_id() must be called first */
959 bpf_map_free_id(map);
960
961 WARN_ON_ONCE(atomic64_read(&map->sleepable_refcnt));
962 if (READ_ONCE(map->free_after_mult_rcu_gp))
963 call_rcu_tasks_trace(&map->rcu, bpf_map_free_mult_rcu_gp);
964 else if (READ_ONCE(map->free_after_rcu_gp))
965 call_rcu(&map->rcu, bpf_map_free_rcu_gp);
966 else
967 bpf_map_free_in_work(map);
968 }
969 }
970 EXPORT_SYMBOL_GPL(bpf_map_put);
971
bpf_map_put_with_uref(struct bpf_map * map)972 void bpf_map_put_with_uref(struct bpf_map *map)
973 {
974 bpf_map_put_uref(map);
975 bpf_map_put(map);
976 }
977
bpf_map_release(struct inode * inode,struct file * filp)978 static int bpf_map_release(struct inode *inode, struct file *filp)
979 {
980 struct bpf_map *map = filp->private_data;
981
982 if (map->ops->map_release)
983 map->ops->map_release(map, filp);
984
985 bpf_map_put_with_uref(map);
986 return 0;
987 }
988
map_get_sys_perms(struct bpf_map * map,struct fd f)989 static fmode_t map_get_sys_perms(struct bpf_map *map, struct fd f)
990 {
991 fmode_t mode = fd_file(f)->f_mode;
992
993 /* Our file permissions may have been overridden by global
994 * map permissions facing syscall side.
995 */
996 if (READ_ONCE(map->frozen))
997 mode &= ~FMODE_CAN_WRITE;
998 return mode;
999 }
1000
1001 #ifdef CONFIG_PROC_FS
1002 /* Show the memory usage of a bpf map */
bpf_map_memory_usage(const struct bpf_map * map)1003 static u64 bpf_map_memory_usage(const struct bpf_map *map)
1004 {
1005 return map->ops->map_mem_usage(map);
1006 }
1007
bpf_map_show_fdinfo(struct seq_file * m,struct file * filp)1008 static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp)
1009 {
1010 struct bpf_map *map = filp->private_data;
1011 u32 type = 0, jited = 0;
1012
1013 spin_lock(&map->owner_lock);
1014 if (map->owner) {
1015 type = map->owner->type;
1016 jited = map->owner->jited;
1017 }
1018 spin_unlock(&map->owner_lock);
1019
1020 seq_printf(m,
1021 "map_type:\t%u\n"
1022 "key_size:\t%u\n"
1023 "value_size:\t%u\n"
1024 "max_entries:\t%u\n"
1025 "map_flags:\t%#x\n"
1026 "map_extra:\t%#llx\n"
1027 "memlock:\t%llu\n"
1028 "map_id:\t%u\n"
1029 "frozen:\t%u\n",
1030 map->map_type,
1031 map->key_size,
1032 map->value_size,
1033 map->max_entries,
1034 map->map_flags,
1035 (unsigned long long)map->map_extra,
1036 bpf_map_memory_usage(map),
1037 map->id,
1038 READ_ONCE(map->frozen));
1039 if (type) {
1040 seq_printf(m, "owner_prog_type:\t%u\n", type);
1041 seq_printf(m, "owner_jited:\t%u\n", jited);
1042 }
1043 }
1044 #endif
1045
bpf_dummy_read(struct file * filp,char __user * buf,size_t siz,loff_t * ppos)1046 static ssize_t bpf_dummy_read(struct file *filp, char __user *buf, size_t siz,
1047 loff_t *ppos)
1048 {
1049 /* We need this handler such that alloc_file() enables
1050 * f_mode with FMODE_CAN_READ.
1051 */
1052 return -EINVAL;
1053 }
1054
bpf_dummy_write(struct file * filp,const char __user * buf,size_t siz,loff_t * ppos)1055 static ssize_t bpf_dummy_write(struct file *filp, const char __user *buf,
1056 size_t siz, loff_t *ppos)
1057 {
1058 /* We need this handler such that alloc_file() enables
1059 * f_mode with FMODE_CAN_WRITE.
1060 */
1061 return -EINVAL;
1062 }
1063
1064 /* called for any extra memory-mapped regions (except initial) */
bpf_map_mmap_open(struct vm_area_struct * vma)1065 static void bpf_map_mmap_open(struct vm_area_struct *vma)
1066 {
1067 struct bpf_map *map = vma->vm_file->private_data;
1068
1069 if (vma->vm_flags & VM_MAYWRITE)
1070 bpf_map_write_active_inc(map);
1071 }
1072
1073 /* called for all unmapped memory region (including initial) */
bpf_map_mmap_close(struct vm_area_struct * vma)1074 static void bpf_map_mmap_close(struct vm_area_struct *vma)
1075 {
1076 struct bpf_map *map = vma->vm_file->private_data;
1077
1078 if (vma->vm_flags & VM_MAYWRITE)
1079 bpf_map_write_active_dec(map);
1080 }
1081
1082 static const struct vm_operations_struct bpf_map_default_vmops = {
1083 .open = bpf_map_mmap_open,
1084 .close = bpf_map_mmap_close,
1085 };
1086
bpf_map_mmap(struct file * filp,struct vm_area_struct * vma)1087 static int bpf_map_mmap(struct file *filp, struct vm_area_struct *vma)
1088 {
1089 struct bpf_map *map = filp->private_data;
1090 int err = 0;
1091
1092 if (!map->ops->map_mmap || !IS_ERR_OR_NULL(map->record))
1093 return -ENOTSUPP;
1094
1095 if (!(vma->vm_flags & VM_SHARED))
1096 return -EINVAL;
1097
1098 mutex_lock(&map->freeze_mutex);
1099
1100 if (vma->vm_flags & VM_WRITE) {
1101 if (map->frozen) {
1102 err = -EPERM;
1103 goto out;
1104 }
1105 /* map is meant to be read-only, so do not allow mapping as
1106 * writable, because it's possible to leak a writable page
1107 * reference and allows user-space to still modify it after
1108 * freezing, while verifier will assume contents do not change
1109 */
1110 if (map->map_flags & BPF_F_RDONLY_PROG) {
1111 err = -EACCES;
1112 goto out;
1113 }
1114 bpf_map_write_active_inc(map);
1115 }
1116 out:
1117 mutex_unlock(&map->freeze_mutex);
1118 if (err)
1119 return err;
1120
1121 /* set default open/close callbacks */
1122 vma->vm_ops = &bpf_map_default_vmops;
1123 vma->vm_private_data = map;
1124 vm_flags_clear(vma, VM_MAYEXEC);
1125 /* If mapping is read-only, then disallow potentially re-mapping with
1126 * PROT_WRITE by dropping VM_MAYWRITE flag. This VM_MAYWRITE clearing
1127 * means that as far as BPF map's memory-mapped VMAs are concerned,
1128 * VM_WRITE and VM_MAYWRITE and equivalent, if one of them is set,
1129 * both should be set, so we can forget about VM_MAYWRITE and always
1130 * check just VM_WRITE
1131 */
1132 if (!(vma->vm_flags & VM_WRITE))
1133 vm_flags_clear(vma, VM_MAYWRITE);
1134
1135 err = map->ops->map_mmap(map, vma);
1136 if (err) {
1137 if (vma->vm_flags & VM_WRITE)
1138 bpf_map_write_active_dec(map);
1139 }
1140
1141 return err;
1142 }
1143
bpf_map_poll(struct file * filp,struct poll_table_struct * pts)1144 static __poll_t bpf_map_poll(struct file *filp, struct poll_table_struct *pts)
1145 {
1146 struct bpf_map *map = filp->private_data;
1147
1148 if (map->ops->map_poll)
1149 return map->ops->map_poll(map, filp, pts);
1150
1151 return EPOLLERR;
1152 }
1153
bpf_get_unmapped_area(struct file * filp,unsigned long addr,unsigned long len,unsigned long pgoff,unsigned long flags)1154 static unsigned long bpf_get_unmapped_area(struct file *filp, unsigned long addr,
1155 unsigned long len, unsigned long pgoff,
1156 unsigned long flags)
1157 {
1158 struct bpf_map *map = filp->private_data;
1159
1160 if (map->ops->map_get_unmapped_area)
1161 return map->ops->map_get_unmapped_area(filp, addr, len, pgoff, flags);
1162 #ifdef CONFIG_MMU
1163 return mm_get_unmapped_area(filp, addr, len, pgoff, flags);
1164 #else
1165 return addr;
1166 #endif
1167 }
1168
1169 const struct file_operations bpf_map_fops = {
1170 #ifdef CONFIG_PROC_FS
1171 .show_fdinfo = bpf_map_show_fdinfo,
1172 #endif
1173 .release = bpf_map_release,
1174 .read = bpf_dummy_read,
1175 .write = bpf_dummy_write,
1176 .mmap = bpf_map_mmap,
1177 .poll = bpf_map_poll,
1178 .get_unmapped_area = bpf_get_unmapped_area,
1179 };
1180
bpf_map_new_fd(struct bpf_map * map,int flags)1181 int bpf_map_new_fd(struct bpf_map *map, int flags)
1182 {
1183 int ret;
1184
1185 ret = security_bpf_map(map, OPEN_FMODE(flags));
1186 if (ret < 0)
1187 return ret;
1188
1189 return anon_inode_getfd("bpf-map", &bpf_map_fops, map,
1190 flags | O_CLOEXEC);
1191 }
1192
bpf_get_file_flag(int flags)1193 int bpf_get_file_flag(int flags)
1194 {
1195 if ((flags & BPF_F_RDONLY) && (flags & BPF_F_WRONLY))
1196 return -EINVAL;
1197 if (flags & BPF_F_RDONLY)
1198 return O_RDONLY;
1199 if (flags & BPF_F_WRONLY)
1200 return O_WRONLY;
1201 return O_RDWR;
1202 }
1203
1204 /* helper macro to check that unused fields 'union bpf_attr' are zero */
1205 #define CHECK_ATTR(CMD) \
1206 memchr_inv((void *) &attr->CMD##_LAST_FIELD + \
1207 sizeof(attr->CMD##_LAST_FIELD), 0, \
1208 sizeof(*attr) - \
1209 offsetof(union bpf_attr, CMD##_LAST_FIELD) - \
1210 sizeof(attr->CMD##_LAST_FIELD)) != NULL
1211
1212 /* dst and src must have at least "size" number of bytes.
1213 * Return strlen on success and < 0 on error.
1214 */
bpf_obj_name_cpy(char * dst,const char * src,unsigned int size)1215 int bpf_obj_name_cpy(char *dst, const char *src, unsigned int size)
1216 {
1217 const char *end = src + size;
1218 const char *orig_src = src;
1219
1220 memset(dst, 0, size);
1221 /* Copy all isalnum(), '_' and '.' chars. */
1222 while (src < end && *src) {
1223 if (!isalnum(*src) &&
1224 *src != '_' && *src != '.')
1225 return -EINVAL;
1226 *dst++ = *src++;
1227 }
1228
1229 /* No '\0' found in "size" number of bytes */
1230 if (src == end)
1231 return -EINVAL;
1232
1233 return src - orig_src;
1234 }
1235 EXPORT_SYMBOL_GPL(bpf_obj_name_cpy);
1236
map_check_no_btf(const struct bpf_map * map,const struct btf * btf,const struct btf_type * key_type,const struct btf_type * value_type)1237 int map_check_no_btf(const struct bpf_map *map,
1238 const struct btf *btf,
1239 const struct btf_type *key_type,
1240 const struct btf_type *value_type)
1241 {
1242 return -ENOTSUPP;
1243 }
1244
map_check_btf(struct bpf_map * map,struct bpf_token * token,const struct btf * btf,u32 btf_key_id,u32 btf_value_id)1245 static int map_check_btf(struct bpf_map *map, struct bpf_token *token,
1246 const struct btf *btf, u32 btf_key_id, u32 btf_value_id)
1247 {
1248 const struct btf_type *key_type, *value_type;
1249 u32 key_size, value_size;
1250 int ret = 0;
1251
1252 /* Some maps allow key to be unspecified. */
1253 if (btf_key_id) {
1254 key_type = btf_type_id_size(btf, &btf_key_id, &key_size);
1255 if (!key_type || key_size != map->key_size)
1256 return -EINVAL;
1257 } else {
1258 key_type = btf_type_by_id(btf, 0);
1259 if (!map->ops->map_check_btf)
1260 return -EINVAL;
1261 }
1262
1263 value_type = btf_type_id_size(btf, &btf_value_id, &value_size);
1264 if (!value_type || value_size != map->value_size)
1265 return -EINVAL;
1266
1267 map->record = btf_parse_fields(btf, value_type,
1268 BPF_SPIN_LOCK | BPF_RES_SPIN_LOCK | BPF_TIMER | BPF_KPTR | BPF_LIST_HEAD |
1269 BPF_RB_ROOT | BPF_REFCOUNT | BPF_WORKQUEUE | BPF_UPTR |
1270 BPF_TASK_WORK,
1271 map->value_size);
1272 if (!IS_ERR_OR_NULL(map->record)) {
1273 int i;
1274
1275 if (!bpf_token_capable(token, CAP_BPF)) {
1276 ret = -EPERM;
1277 goto free_map_tab;
1278 }
1279 if (map->map_flags & (BPF_F_RDONLY_PROG | BPF_F_WRONLY_PROG)) {
1280 ret = -EACCES;
1281 goto free_map_tab;
1282 }
1283 for (i = 0; i < sizeof(map->record->field_mask) * 8; i++) {
1284 switch (map->record->field_mask & (1 << i)) {
1285 case 0:
1286 continue;
1287 case BPF_SPIN_LOCK:
1288 case BPF_RES_SPIN_LOCK:
1289 if (map->map_type != BPF_MAP_TYPE_HASH &&
1290 map->map_type != BPF_MAP_TYPE_ARRAY &&
1291 map->map_type != BPF_MAP_TYPE_CGROUP_STORAGE &&
1292 map->map_type != BPF_MAP_TYPE_SK_STORAGE &&
1293 map->map_type != BPF_MAP_TYPE_INODE_STORAGE &&
1294 map->map_type != BPF_MAP_TYPE_TASK_STORAGE &&
1295 map->map_type != BPF_MAP_TYPE_CGRP_STORAGE) {
1296 ret = -EOPNOTSUPP;
1297 goto free_map_tab;
1298 }
1299 break;
1300 case BPF_TIMER:
1301 case BPF_WORKQUEUE:
1302 case BPF_TASK_WORK:
1303 if (map->map_type != BPF_MAP_TYPE_HASH &&
1304 map->map_type != BPF_MAP_TYPE_LRU_HASH &&
1305 map->map_type != BPF_MAP_TYPE_ARRAY) {
1306 ret = -EOPNOTSUPP;
1307 goto free_map_tab;
1308 }
1309 break;
1310 case BPF_KPTR_UNREF:
1311 case BPF_KPTR_REF:
1312 case BPF_KPTR_PERCPU:
1313 case BPF_REFCOUNT:
1314 if (map->map_type != BPF_MAP_TYPE_HASH &&
1315 map->map_type != BPF_MAP_TYPE_PERCPU_HASH &&
1316 map->map_type != BPF_MAP_TYPE_LRU_HASH &&
1317 map->map_type != BPF_MAP_TYPE_LRU_PERCPU_HASH &&
1318 map->map_type != BPF_MAP_TYPE_ARRAY &&
1319 map->map_type != BPF_MAP_TYPE_PERCPU_ARRAY &&
1320 map->map_type != BPF_MAP_TYPE_SK_STORAGE &&
1321 map->map_type != BPF_MAP_TYPE_INODE_STORAGE &&
1322 map->map_type != BPF_MAP_TYPE_TASK_STORAGE &&
1323 map->map_type != BPF_MAP_TYPE_CGRP_STORAGE) {
1324 ret = -EOPNOTSUPP;
1325 goto free_map_tab;
1326 }
1327 break;
1328 case BPF_UPTR:
1329 if (map->map_type != BPF_MAP_TYPE_TASK_STORAGE) {
1330 ret = -EOPNOTSUPP;
1331 goto free_map_tab;
1332 }
1333 break;
1334 case BPF_LIST_HEAD:
1335 case BPF_RB_ROOT:
1336 if (map->map_type != BPF_MAP_TYPE_HASH &&
1337 map->map_type != BPF_MAP_TYPE_LRU_HASH &&
1338 map->map_type != BPF_MAP_TYPE_ARRAY) {
1339 ret = -EOPNOTSUPP;
1340 goto free_map_tab;
1341 }
1342 break;
1343 default:
1344 /* Fail if map_type checks are missing for a field type */
1345 ret = -EOPNOTSUPP;
1346 goto free_map_tab;
1347 }
1348 }
1349 }
1350
1351 ret = btf_check_and_fixup_fields(btf, map->record);
1352 if (ret < 0)
1353 goto free_map_tab;
1354
1355 if (map->ops->map_check_btf) {
1356 ret = map->ops->map_check_btf(map, btf, key_type, value_type);
1357 if (ret < 0)
1358 goto free_map_tab;
1359 }
1360
1361 return ret;
1362 free_map_tab:
1363 bpf_map_free_record(map);
1364 return ret;
1365 }
1366
1367 #define BPF_MAP_CREATE_LAST_FIELD excl_prog_hash_size
1368 /* called via syscall */
map_create(union bpf_attr * attr,bpfptr_t uattr)1369 static int map_create(union bpf_attr *attr, bpfptr_t uattr)
1370 {
1371 const struct bpf_map_ops *ops;
1372 struct bpf_token *token = NULL;
1373 int numa_node = bpf_map_attr_numa_node(attr);
1374 u32 map_type = attr->map_type;
1375 struct bpf_map *map;
1376 bool token_flag;
1377 int f_flags;
1378 int err;
1379
1380 err = CHECK_ATTR(BPF_MAP_CREATE);
1381 if (err)
1382 return -EINVAL;
1383
1384 /* check BPF_F_TOKEN_FD flag, remember if it's set, and then clear it
1385 * to avoid per-map type checks tripping on unknown flag
1386 */
1387 token_flag = attr->map_flags & BPF_F_TOKEN_FD;
1388 attr->map_flags &= ~BPF_F_TOKEN_FD;
1389
1390 if (attr->btf_vmlinux_value_type_id) {
1391 if (attr->map_type != BPF_MAP_TYPE_STRUCT_OPS ||
1392 attr->btf_key_type_id || attr->btf_value_type_id)
1393 return -EINVAL;
1394 } else if (attr->btf_key_type_id && !attr->btf_value_type_id) {
1395 return -EINVAL;
1396 }
1397
1398 if (attr->map_type != BPF_MAP_TYPE_BLOOM_FILTER &&
1399 attr->map_type != BPF_MAP_TYPE_ARENA &&
1400 attr->map_extra != 0)
1401 return -EINVAL;
1402
1403 f_flags = bpf_get_file_flag(attr->map_flags);
1404 if (f_flags < 0)
1405 return f_flags;
1406
1407 if (numa_node != NUMA_NO_NODE &&
1408 ((unsigned int)numa_node >= nr_node_ids ||
1409 !node_online(numa_node)))
1410 return -EINVAL;
1411
1412 /* find map type and init map: hashtable vs rbtree vs bloom vs ... */
1413 map_type = attr->map_type;
1414 if (map_type >= ARRAY_SIZE(bpf_map_types))
1415 return -EINVAL;
1416 map_type = array_index_nospec(map_type, ARRAY_SIZE(bpf_map_types));
1417 ops = bpf_map_types[map_type];
1418 if (!ops)
1419 return -EINVAL;
1420
1421 if (ops->map_alloc_check) {
1422 err = ops->map_alloc_check(attr);
1423 if (err)
1424 return err;
1425 }
1426 if (attr->map_ifindex)
1427 ops = &bpf_map_offload_ops;
1428 if (!ops->map_mem_usage)
1429 return -EINVAL;
1430
1431 if (token_flag) {
1432 token = bpf_token_get_from_fd(attr->map_token_fd);
1433 if (IS_ERR(token))
1434 return PTR_ERR(token);
1435
1436 /* if current token doesn't grant map creation permissions,
1437 * then we can't use this token, so ignore it and rely on
1438 * system-wide capabilities checks
1439 */
1440 if (!bpf_token_allow_cmd(token, BPF_MAP_CREATE) ||
1441 !bpf_token_allow_map_type(token, attr->map_type)) {
1442 bpf_token_put(token);
1443 token = NULL;
1444 }
1445 }
1446
1447 err = -EPERM;
1448
1449 /* Intent here is for unprivileged_bpf_disabled to block BPF map
1450 * creation for unprivileged users; other actions depend
1451 * on fd availability and access to bpffs, so are dependent on
1452 * object creation success. Even with unprivileged BPF disabled,
1453 * capability checks are still carried out.
1454 */
1455 if (sysctl_unprivileged_bpf_disabled && !bpf_token_capable(token, CAP_BPF))
1456 goto put_token;
1457
1458 /* check privileged map type permissions */
1459 switch (map_type) {
1460 case BPF_MAP_TYPE_ARRAY:
1461 case BPF_MAP_TYPE_PERCPU_ARRAY:
1462 case BPF_MAP_TYPE_PROG_ARRAY:
1463 case BPF_MAP_TYPE_PERF_EVENT_ARRAY:
1464 case BPF_MAP_TYPE_CGROUP_ARRAY:
1465 case BPF_MAP_TYPE_ARRAY_OF_MAPS:
1466 case BPF_MAP_TYPE_HASH:
1467 case BPF_MAP_TYPE_PERCPU_HASH:
1468 case BPF_MAP_TYPE_HASH_OF_MAPS:
1469 case BPF_MAP_TYPE_RINGBUF:
1470 case BPF_MAP_TYPE_USER_RINGBUF:
1471 case BPF_MAP_TYPE_CGROUP_STORAGE:
1472 case BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE:
1473 /* unprivileged */
1474 break;
1475 case BPF_MAP_TYPE_SK_STORAGE:
1476 case BPF_MAP_TYPE_INODE_STORAGE:
1477 case BPF_MAP_TYPE_TASK_STORAGE:
1478 case BPF_MAP_TYPE_CGRP_STORAGE:
1479 case BPF_MAP_TYPE_BLOOM_FILTER:
1480 case BPF_MAP_TYPE_LPM_TRIE:
1481 case BPF_MAP_TYPE_REUSEPORT_SOCKARRAY:
1482 case BPF_MAP_TYPE_STACK_TRACE:
1483 case BPF_MAP_TYPE_QUEUE:
1484 case BPF_MAP_TYPE_STACK:
1485 case BPF_MAP_TYPE_LRU_HASH:
1486 case BPF_MAP_TYPE_LRU_PERCPU_HASH:
1487 case BPF_MAP_TYPE_STRUCT_OPS:
1488 case BPF_MAP_TYPE_CPUMAP:
1489 case BPF_MAP_TYPE_ARENA:
1490 case BPF_MAP_TYPE_INSN_ARRAY:
1491 if (!bpf_token_capable(token, CAP_BPF))
1492 goto put_token;
1493 break;
1494 case BPF_MAP_TYPE_SOCKMAP:
1495 case BPF_MAP_TYPE_SOCKHASH:
1496 case BPF_MAP_TYPE_DEVMAP:
1497 case BPF_MAP_TYPE_DEVMAP_HASH:
1498 case BPF_MAP_TYPE_XSKMAP:
1499 if (!bpf_token_capable(token, CAP_NET_ADMIN))
1500 goto put_token;
1501 break;
1502 default:
1503 WARN(1, "unsupported map type %d", map_type);
1504 goto put_token;
1505 }
1506
1507 map = ops->map_alloc(attr);
1508 if (IS_ERR(map)) {
1509 err = PTR_ERR(map);
1510 goto put_token;
1511 }
1512 map->ops = ops;
1513 map->map_type = map_type;
1514
1515 err = bpf_obj_name_cpy(map->name, attr->map_name,
1516 sizeof(attr->map_name));
1517 if (err < 0)
1518 goto free_map;
1519
1520 preempt_disable();
1521 map->cookie = gen_cookie_next(&bpf_map_cookie);
1522 preempt_enable();
1523
1524 atomic64_set(&map->refcnt, 1);
1525 atomic64_set(&map->usercnt, 1);
1526 mutex_init(&map->freeze_mutex);
1527 spin_lock_init(&map->owner_lock);
1528
1529 if (attr->btf_key_type_id || attr->btf_value_type_id ||
1530 /* Even the map's value is a kernel's struct,
1531 * the bpf_prog.o must have BTF to begin with
1532 * to figure out the corresponding kernel's
1533 * counter part. Thus, attr->btf_fd has
1534 * to be valid also.
1535 */
1536 attr->btf_vmlinux_value_type_id) {
1537 struct btf *btf;
1538
1539 btf = btf_get_by_fd(attr->btf_fd);
1540 if (IS_ERR(btf)) {
1541 err = PTR_ERR(btf);
1542 goto free_map;
1543 }
1544 if (btf_is_kernel(btf)) {
1545 btf_put(btf);
1546 err = -EACCES;
1547 goto free_map;
1548 }
1549 map->btf = btf;
1550
1551 if (attr->btf_value_type_id) {
1552 err = map_check_btf(map, token, btf, attr->btf_key_type_id,
1553 attr->btf_value_type_id);
1554 if (err)
1555 goto free_map;
1556 }
1557
1558 map->btf_key_type_id = attr->btf_key_type_id;
1559 map->btf_value_type_id = attr->btf_value_type_id;
1560 map->btf_vmlinux_value_type_id =
1561 attr->btf_vmlinux_value_type_id;
1562 }
1563
1564 if (attr->excl_prog_hash) {
1565 bpfptr_t uprog_hash = make_bpfptr(attr->excl_prog_hash, uattr.is_kernel);
1566
1567 if (attr->excl_prog_hash_size != SHA256_DIGEST_SIZE) {
1568 err = -EINVAL;
1569 goto free_map;
1570 }
1571
1572 map->excl_prog_sha = kzalloc(SHA256_DIGEST_SIZE, GFP_KERNEL);
1573 if (!map->excl_prog_sha) {
1574 err = -ENOMEM;
1575 goto free_map;
1576 }
1577
1578 if (copy_from_bpfptr(map->excl_prog_sha, uprog_hash, SHA256_DIGEST_SIZE)) {
1579 err = -EFAULT;
1580 goto free_map;
1581 }
1582 } else if (attr->excl_prog_hash_size) {
1583 err = -EINVAL;
1584 goto free_map;
1585 }
1586
1587 err = security_bpf_map_create(map, attr, token, uattr.is_kernel);
1588 if (err)
1589 goto free_map_sec;
1590
1591 err = bpf_map_alloc_id(map);
1592 if (err)
1593 goto free_map_sec;
1594
1595 bpf_map_save_memcg(map);
1596 bpf_token_put(token);
1597
1598 err = bpf_map_new_fd(map, f_flags);
1599 if (err < 0) {
1600 /* failed to allocate fd.
1601 * bpf_map_put_with_uref() is needed because the above
1602 * bpf_map_alloc_id() has published the map
1603 * to the userspace and the userspace may
1604 * have refcnt-ed it through BPF_MAP_GET_FD_BY_ID.
1605 */
1606 bpf_map_put_with_uref(map);
1607 return err;
1608 }
1609
1610 return err;
1611
1612 free_map_sec:
1613 security_bpf_map_free(map);
1614 free_map:
1615 bpf_map_free(map);
1616 put_token:
1617 bpf_token_put(token);
1618 return err;
1619 }
1620
bpf_map_inc(struct bpf_map * map)1621 void bpf_map_inc(struct bpf_map *map)
1622 {
1623 atomic64_inc(&map->refcnt);
1624 }
1625 EXPORT_SYMBOL_GPL(bpf_map_inc);
1626
bpf_map_inc_with_uref(struct bpf_map * map)1627 void bpf_map_inc_with_uref(struct bpf_map *map)
1628 {
1629 atomic64_inc(&map->refcnt);
1630 atomic64_inc(&map->usercnt);
1631 }
1632 EXPORT_SYMBOL_GPL(bpf_map_inc_with_uref);
1633
bpf_map_get(u32 ufd)1634 struct bpf_map *bpf_map_get(u32 ufd)
1635 {
1636 CLASS(fd, f)(ufd);
1637 struct bpf_map *map = __bpf_map_get(f);
1638
1639 if (!IS_ERR(map))
1640 bpf_map_inc(map);
1641
1642 return map;
1643 }
1644 EXPORT_SYMBOL_NS(bpf_map_get, "BPF_INTERNAL");
1645
bpf_map_get_with_uref(u32 ufd)1646 struct bpf_map *bpf_map_get_with_uref(u32 ufd)
1647 {
1648 CLASS(fd, f)(ufd);
1649 struct bpf_map *map = __bpf_map_get(f);
1650
1651 if (!IS_ERR(map))
1652 bpf_map_inc_with_uref(map);
1653
1654 return map;
1655 }
1656
1657 /* map_idr_lock should have been held or the map should have been
1658 * protected by rcu read lock.
1659 */
__bpf_map_inc_not_zero(struct bpf_map * map,bool uref)1660 struct bpf_map *__bpf_map_inc_not_zero(struct bpf_map *map, bool uref)
1661 {
1662 int refold;
1663
1664 refold = atomic64_fetch_add_unless(&map->refcnt, 1, 0);
1665 if (!refold)
1666 return ERR_PTR(-ENOENT);
1667 if (uref)
1668 atomic64_inc(&map->usercnt);
1669
1670 return map;
1671 }
1672
bpf_map_inc_not_zero(struct bpf_map * map)1673 struct bpf_map *bpf_map_inc_not_zero(struct bpf_map *map)
1674 {
1675 lockdep_assert(rcu_read_lock_held());
1676 return __bpf_map_inc_not_zero(map, false);
1677 }
1678 EXPORT_SYMBOL_GPL(bpf_map_inc_not_zero);
1679
bpf_stackmap_extract(struct bpf_map * map,void * key,void * value,bool delete)1680 int __weak bpf_stackmap_extract(struct bpf_map *map, void *key, void *value,
1681 bool delete)
1682 {
1683 return -ENOTSUPP;
1684 }
1685
__bpf_copy_key(void __user * ukey,u64 key_size)1686 static void *__bpf_copy_key(void __user *ukey, u64 key_size)
1687 {
1688 if (key_size)
1689 return vmemdup_user(ukey, key_size);
1690
1691 if (ukey)
1692 return ERR_PTR(-EINVAL);
1693
1694 return NULL;
1695 }
1696
___bpf_copy_key(bpfptr_t ukey,u64 key_size)1697 static void *___bpf_copy_key(bpfptr_t ukey, u64 key_size)
1698 {
1699 if (key_size)
1700 return kvmemdup_bpfptr(ukey, key_size);
1701
1702 if (!bpfptr_is_null(ukey))
1703 return ERR_PTR(-EINVAL);
1704
1705 return NULL;
1706 }
1707
1708 /* last field in 'union bpf_attr' used by this command */
1709 #define BPF_MAP_LOOKUP_ELEM_LAST_FIELD flags
1710
map_lookup_elem(union bpf_attr * attr)1711 static int map_lookup_elem(union bpf_attr *attr)
1712 {
1713 void __user *ukey = u64_to_user_ptr(attr->key);
1714 void __user *uvalue = u64_to_user_ptr(attr->value);
1715 struct bpf_map *map;
1716 void *key, *value;
1717 u32 value_size;
1718 int err;
1719
1720 if (CHECK_ATTR(BPF_MAP_LOOKUP_ELEM))
1721 return -EINVAL;
1722
1723 CLASS(fd, f)(attr->map_fd);
1724 map = __bpf_map_get(f);
1725 if (IS_ERR(map))
1726 return PTR_ERR(map);
1727 if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ))
1728 return -EPERM;
1729
1730 err = bpf_map_check_op_flags(map, attr->flags, BPF_F_LOCK | BPF_F_CPU);
1731 if (err)
1732 return err;
1733
1734 key = __bpf_copy_key(ukey, map->key_size);
1735 if (IS_ERR(key))
1736 return PTR_ERR(key);
1737
1738 value_size = bpf_map_value_size(map, attr->flags);
1739
1740 err = -ENOMEM;
1741 value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN);
1742 if (!value)
1743 goto free_key;
1744
1745 if (map->map_type == BPF_MAP_TYPE_BLOOM_FILTER) {
1746 if (copy_from_user(value, uvalue, value_size))
1747 err = -EFAULT;
1748 else
1749 err = bpf_map_copy_value(map, key, value, attr->flags);
1750 goto free_value;
1751 }
1752
1753 err = bpf_map_copy_value(map, key, value, attr->flags);
1754 if (err)
1755 goto free_value;
1756
1757 err = -EFAULT;
1758 if (copy_to_user(uvalue, value, value_size) != 0)
1759 goto free_value;
1760
1761 err = 0;
1762
1763 free_value:
1764 kvfree(value);
1765 free_key:
1766 kvfree(key);
1767 return err;
1768 }
1769
1770
1771 #define BPF_MAP_UPDATE_ELEM_LAST_FIELD flags
1772
map_update_elem(union bpf_attr * attr,bpfptr_t uattr)1773 static int map_update_elem(union bpf_attr *attr, bpfptr_t uattr)
1774 {
1775 bpfptr_t ukey = make_bpfptr(attr->key, uattr.is_kernel);
1776 bpfptr_t uvalue = make_bpfptr(attr->value, uattr.is_kernel);
1777 struct bpf_map *map;
1778 void *key, *value;
1779 u32 value_size;
1780 int err;
1781
1782 if (CHECK_ATTR(BPF_MAP_UPDATE_ELEM))
1783 return -EINVAL;
1784
1785 CLASS(fd, f)(attr->map_fd);
1786 map = __bpf_map_get(f);
1787 if (IS_ERR(map))
1788 return PTR_ERR(map);
1789 bpf_map_write_active_inc(map);
1790 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
1791 err = -EPERM;
1792 goto err_put;
1793 }
1794
1795 err = bpf_map_check_op_flags(map, attr->flags, ~0);
1796 if (err)
1797 goto err_put;
1798
1799 key = ___bpf_copy_key(ukey, map->key_size);
1800 if (IS_ERR(key)) {
1801 err = PTR_ERR(key);
1802 goto err_put;
1803 }
1804
1805 value_size = bpf_map_value_size(map, attr->flags);
1806 value = kvmemdup_bpfptr(uvalue, value_size);
1807 if (IS_ERR(value)) {
1808 err = PTR_ERR(value);
1809 goto free_key;
1810 }
1811
1812 err = bpf_map_update_value(map, fd_file(f), key, value, attr->flags);
1813 if (!err)
1814 maybe_wait_bpf_programs(map);
1815
1816 kvfree(value);
1817 free_key:
1818 kvfree(key);
1819 err_put:
1820 bpf_map_write_active_dec(map);
1821 return err;
1822 }
1823
1824 #define BPF_MAP_DELETE_ELEM_LAST_FIELD key
1825
map_delete_elem(union bpf_attr * attr,bpfptr_t uattr)1826 static int map_delete_elem(union bpf_attr *attr, bpfptr_t uattr)
1827 {
1828 bpfptr_t ukey = make_bpfptr(attr->key, uattr.is_kernel);
1829 struct bpf_map *map;
1830 void *key;
1831 int err;
1832
1833 if (CHECK_ATTR(BPF_MAP_DELETE_ELEM))
1834 return -EINVAL;
1835
1836 CLASS(fd, f)(attr->map_fd);
1837 map = __bpf_map_get(f);
1838 if (IS_ERR(map))
1839 return PTR_ERR(map);
1840 bpf_map_write_active_inc(map);
1841 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
1842 err = -EPERM;
1843 goto err_put;
1844 }
1845
1846 key = ___bpf_copy_key(ukey, map->key_size);
1847 if (IS_ERR(key)) {
1848 err = PTR_ERR(key);
1849 goto err_put;
1850 }
1851
1852 if (bpf_map_is_offloaded(map)) {
1853 err = bpf_map_offload_delete_elem(map, key);
1854 goto out;
1855 } else if (IS_FD_PROG_ARRAY(map) ||
1856 map->map_type == BPF_MAP_TYPE_STRUCT_OPS) {
1857 /* These maps require sleepable context */
1858 err = map->ops->map_delete_elem(map, key);
1859 goto out;
1860 }
1861
1862 bpf_disable_instrumentation();
1863 rcu_read_lock();
1864 err = map->ops->map_delete_elem(map, key);
1865 rcu_read_unlock();
1866 bpf_enable_instrumentation();
1867 if (!err)
1868 maybe_wait_bpf_programs(map);
1869 out:
1870 kvfree(key);
1871 err_put:
1872 bpf_map_write_active_dec(map);
1873 return err;
1874 }
1875
1876 /* last field in 'union bpf_attr' used by this command */
1877 #define BPF_MAP_GET_NEXT_KEY_LAST_FIELD next_key
1878
map_get_next_key(union bpf_attr * attr)1879 static int map_get_next_key(union bpf_attr *attr)
1880 {
1881 void __user *ukey = u64_to_user_ptr(attr->key);
1882 void __user *unext_key = u64_to_user_ptr(attr->next_key);
1883 struct bpf_map *map;
1884 void *key, *next_key;
1885 int err;
1886
1887 if (CHECK_ATTR(BPF_MAP_GET_NEXT_KEY))
1888 return -EINVAL;
1889
1890 CLASS(fd, f)(attr->map_fd);
1891 map = __bpf_map_get(f);
1892 if (IS_ERR(map))
1893 return PTR_ERR(map);
1894 if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ))
1895 return -EPERM;
1896
1897 if (ukey) {
1898 key = __bpf_copy_key(ukey, map->key_size);
1899 if (IS_ERR(key))
1900 return PTR_ERR(key);
1901 } else {
1902 key = NULL;
1903 }
1904
1905 err = -ENOMEM;
1906 next_key = kvmalloc(map->key_size, GFP_USER);
1907 if (!next_key)
1908 goto free_key;
1909
1910 if (bpf_map_is_offloaded(map)) {
1911 err = bpf_map_offload_get_next_key(map, key, next_key);
1912 goto out;
1913 }
1914
1915 rcu_read_lock();
1916 err = map->ops->map_get_next_key(map, key, next_key);
1917 rcu_read_unlock();
1918 out:
1919 if (err)
1920 goto free_next_key;
1921
1922 err = -EFAULT;
1923 if (copy_to_user(unext_key, next_key, map->key_size) != 0)
1924 goto free_next_key;
1925
1926 err = 0;
1927
1928 free_next_key:
1929 kvfree(next_key);
1930 free_key:
1931 kvfree(key);
1932 return err;
1933 }
1934
generic_map_delete_batch(struct bpf_map * map,const union bpf_attr * attr,union bpf_attr __user * uattr)1935 int generic_map_delete_batch(struct bpf_map *map,
1936 const union bpf_attr *attr,
1937 union bpf_attr __user *uattr)
1938 {
1939 void __user *keys = u64_to_user_ptr(attr->batch.keys);
1940 u32 cp, max_count;
1941 int err = 0;
1942 void *key;
1943
1944 if (attr->batch.elem_flags & ~BPF_F_LOCK)
1945 return -EINVAL;
1946
1947 if ((attr->batch.elem_flags & BPF_F_LOCK) &&
1948 !btf_record_has_field(map->record, BPF_SPIN_LOCK)) {
1949 return -EINVAL;
1950 }
1951
1952 max_count = attr->batch.count;
1953 if (!max_count)
1954 return 0;
1955
1956 if (put_user(0, &uattr->batch.count))
1957 return -EFAULT;
1958
1959 key = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN);
1960 if (!key)
1961 return -ENOMEM;
1962
1963 for (cp = 0; cp < max_count; cp++) {
1964 err = -EFAULT;
1965 if (copy_from_user(key, keys + cp * map->key_size,
1966 map->key_size))
1967 break;
1968
1969 if (bpf_map_is_offloaded(map)) {
1970 err = bpf_map_offload_delete_elem(map, key);
1971 break;
1972 }
1973
1974 bpf_disable_instrumentation();
1975 rcu_read_lock();
1976 err = map->ops->map_delete_elem(map, key);
1977 rcu_read_unlock();
1978 bpf_enable_instrumentation();
1979 if (err)
1980 break;
1981 cond_resched();
1982 }
1983 if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp)))
1984 err = -EFAULT;
1985
1986 kvfree(key);
1987
1988 return err;
1989 }
1990
generic_map_update_batch(struct bpf_map * map,struct file * map_file,const union bpf_attr * attr,union bpf_attr __user * uattr)1991 int generic_map_update_batch(struct bpf_map *map, struct file *map_file,
1992 const union bpf_attr *attr,
1993 union bpf_attr __user *uattr)
1994 {
1995 void __user *values = u64_to_user_ptr(attr->batch.values);
1996 void __user *keys = u64_to_user_ptr(attr->batch.keys);
1997 u32 value_size, cp, max_count;
1998 void *key, *value;
1999 int err = 0;
2000
2001 err = bpf_map_check_op_flags(map, attr->batch.elem_flags,
2002 BPF_F_LOCK | BPF_F_CPU | BPF_F_ALL_CPUS);
2003 if (err)
2004 return err;
2005
2006 value_size = bpf_map_value_size(map, attr->batch.elem_flags);
2007
2008 max_count = attr->batch.count;
2009 if (!max_count)
2010 return 0;
2011
2012 if (put_user(0, &uattr->batch.count))
2013 return -EFAULT;
2014
2015 key = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN);
2016 if (!key)
2017 return -ENOMEM;
2018
2019 value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN);
2020 if (!value) {
2021 kvfree(key);
2022 return -ENOMEM;
2023 }
2024
2025 for (cp = 0; cp < max_count; cp++) {
2026 err = -EFAULT;
2027 if (copy_from_user(key, keys + cp * map->key_size,
2028 map->key_size) ||
2029 copy_from_user(value, values + cp * value_size, value_size))
2030 break;
2031
2032 err = bpf_map_update_value(map, map_file, key, value,
2033 attr->batch.elem_flags);
2034
2035 if (err)
2036 break;
2037 cond_resched();
2038 }
2039
2040 if (copy_to_user(&uattr->batch.count, &cp, sizeof(cp)))
2041 err = -EFAULT;
2042
2043 kvfree(value);
2044 kvfree(key);
2045
2046 return err;
2047 }
2048
generic_map_lookup_batch(struct bpf_map * map,const union bpf_attr * attr,union bpf_attr __user * uattr)2049 int generic_map_lookup_batch(struct bpf_map *map,
2050 const union bpf_attr *attr,
2051 union bpf_attr __user *uattr)
2052 {
2053 void __user *uobatch = u64_to_user_ptr(attr->batch.out_batch);
2054 void __user *ubatch = u64_to_user_ptr(attr->batch.in_batch);
2055 void __user *values = u64_to_user_ptr(attr->batch.values);
2056 void __user *keys = u64_to_user_ptr(attr->batch.keys);
2057 void *buf, *buf_prevkey, *prev_key, *key, *value;
2058 u32 value_size, cp, max_count;
2059 int err;
2060
2061 err = bpf_map_check_op_flags(map, attr->batch.elem_flags, BPF_F_LOCK | BPF_F_CPU);
2062 if (err)
2063 return err;
2064
2065 value_size = bpf_map_value_size(map, attr->batch.elem_flags);
2066
2067 max_count = attr->batch.count;
2068 if (!max_count)
2069 return 0;
2070
2071 if (put_user(0, &uattr->batch.count))
2072 return -EFAULT;
2073
2074 buf_prevkey = kvmalloc(map->key_size, GFP_USER | __GFP_NOWARN);
2075 if (!buf_prevkey)
2076 return -ENOMEM;
2077
2078 buf = kvmalloc(map->key_size + value_size, GFP_USER | __GFP_NOWARN);
2079 if (!buf) {
2080 kvfree(buf_prevkey);
2081 return -ENOMEM;
2082 }
2083
2084 err = -EFAULT;
2085 prev_key = NULL;
2086 if (ubatch && copy_from_user(buf_prevkey, ubatch, map->key_size))
2087 goto free_buf;
2088 key = buf;
2089 value = key + map->key_size;
2090 if (ubatch)
2091 prev_key = buf_prevkey;
2092
2093 for (cp = 0; cp < max_count;) {
2094 rcu_read_lock();
2095 err = map->ops->map_get_next_key(map, prev_key, key);
2096 rcu_read_unlock();
2097 if (err)
2098 break;
2099 err = bpf_map_copy_value(map, key, value,
2100 attr->batch.elem_flags);
2101
2102 if (err == -ENOENT)
2103 goto next_key;
2104
2105 if (err)
2106 goto free_buf;
2107
2108 if (copy_to_user(keys + cp * map->key_size, key,
2109 map->key_size)) {
2110 err = -EFAULT;
2111 goto free_buf;
2112 }
2113 if (copy_to_user(values + cp * value_size, value, value_size)) {
2114 err = -EFAULT;
2115 goto free_buf;
2116 }
2117
2118 cp++;
2119 next_key:
2120 if (!prev_key)
2121 prev_key = buf_prevkey;
2122
2123 swap(prev_key, key);
2124 cond_resched();
2125 }
2126
2127 if (err == -EFAULT)
2128 goto free_buf;
2129
2130 if ((copy_to_user(&uattr->batch.count, &cp, sizeof(cp)) ||
2131 (cp && copy_to_user(uobatch, prev_key, map->key_size))))
2132 err = -EFAULT;
2133
2134 free_buf:
2135 kvfree(buf_prevkey);
2136 kvfree(buf);
2137 return err;
2138 }
2139
2140 #define BPF_MAP_LOOKUP_AND_DELETE_ELEM_LAST_FIELD flags
2141
map_lookup_and_delete_elem(union bpf_attr * attr)2142 static int map_lookup_and_delete_elem(union bpf_attr *attr)
2143 {
2144 void __user *ukey = u64_to_user_ptr(attr->key);
2145 void __user *uvalue = u64_to_user_ptr(attr->value);
2146 struct bpf_map *map;
2147 void *key, *value;
2148 u32 value_size;
2149 int err;
2150
2151 if (CHECK_ATTR(BPF_MAP_LOOKUP_AND_DELETE_ELEM))
2152 return -EINVAL;
2153
2154 if (attr->flags & ~BPF_F_LOCK)
2155 return -EINVAL;
2156
2157 CLASS(fd, f)(attr->map_fd);
2158 map = __bpf_map_get(f);
2159 if (IS_ERR(map))
2160 return PTR_ERR(map);
2161 bpf_map_write_active_inc(map);
2162 if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ) ||
2163 !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
2164 err = -EPERM;
2165 goto err_put;
2166 }
2167
2168 if (attr->flags &&
2169 (map->map_type == BPF_MAP_TYPE_QUEUE ||
2170 map->map_type == BPF_MAP_TYPE_STACK)) {
2171 err = -EINVAL;
2172 goto err_put;
2173 }
2174
2175 if ((attr->flags & BPF_F_LOCK) &&
2176 !btf_record_has_field(map->record, BPF_SPIN_LOCK)) {
2177 err = -EINVAL;
2178 goto err_put;
2179 }
2180
2181 key = __bpf_copy_key(ukey, map->key_size);
2182 if (IS_ERR(key)) {
2183 err = PTR_ERR(key);
2184 goto err_put;
2185 }
2186
2187 value_size = bpf_map_value_size(map, 0);
2188
2189 err = -ENOMEM;
2190 value = kvmalloc(value_size, GFP_USER | __GFP_NOWARN);
2191 if (!value)
2192 goto free_key;
2193
2194 err = -ENOTSUPP;
2195 if (map->map_type == BPF_MAP_TYPE_QUEUE ||
2196 map->map_type == BPF_MAP_TYPE_STACK) {
2197 err = map->ops->map_pop_elem(map, value);
2198 } else if (map->map_type == BPF_MAP_TYPE_HASH ||
2199 map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
2200 map->map_type == BPF_MAP_TYPE_LRU_HASH ||
2201 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH ||
2202 map->map_type == BPF_MAP_TYPE_STACK_TRACE) {
2203 if (!bpf_map_is_offloaded(map)) {
2204 bpf_disable_instrumentation();
2205 rcu_read_lock();
2206 err = map->ops->map_lookup_and_delete_elem(map, key, value, attr->flags);
2207 rcu_read_unlock();
2208 bpf_enable_instrumentation();
2209 }
2210 }
2211
2212 if (err)
2213 goto free_value;
2214
2215 if (copy_to_user(uvalue, value, value_size) != 0) {
2216 err = -EFAULT;
2217 goto free_value;
2218 }
2219
2220 err = 0;
2221
2222 free_value:
2223 kvfree(value);
2224 free_key:
2225 kvfree(key);
2226 err_put:
2227 bpf_map_write_active_dec(map);
2228 return err;
2229 }
2230
2231 #define BPF_MAP_FREEZE_LAST_FIELD map_fd
2232
map_freeze(const union bpf_attr * attr)2233 static int map_freeze(const union bpf_attr *attr)
2234 {
2235 int err = 0;
2236 struct bpf_map *map;
2237
2238 if (CHECK_ATTR(BPF_MAP_FREEZE))
2239 return -EINVAL;
2240
2241 CLASS(fd, f)(attr->map_fd);
2242 map = __bpf_map_get(f);
2243 if (IS_ERR(map))
2244 return PTR_ERR(map);
2245
2246 if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS || !IS_ERR_OR_NULL(map->record))
2247 return -ENOTSUPP;
2248
2249 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE))
2250 return -EPERM;
2251
2252 mutex_lock(&map->freeze_mutex);
2253 if (bpf_map_write_active(map)) {
2254 err = -EBUSY;
2255 goto err_put;
2256 }
2257 if (READ_ONCE(map->frozen)) {
2258 err = -EBUSY;
2259 goto err_put;
2260 }
2261
2262 WRITE_ONCE(map->frozen, true);
2263 err_put:
2264 mutex_unlock(&map->freeze_mutex);
2265 return err;
2266 }
2267
2268 static const struct bpf_prog_ops * const bpf_prog_types[] = {
2269 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type) \
2270 [_id] = & _name ## _prog_ops,
2271 #define BPF_MAP_TYPE(_id, _ops)
2272 #define BPF_LINK_TYPE(_id, _name)
2273 #include <linux/bpf_types.h>
2274 #undef BPF_PROG_TYPE
2275 #undef BPF_MAP_TYPE
2276 #undef BPF_LINK_TYPE
2277 };
2278
find_prog_type(enum bpf_prog_type type,struct bpf_prog * prog)2279 static int find_prog_type(enum bpf_prog_type type, struct bpf_prog *prog)
2280 {
2281 const struct bpf_prog_ops *ops;
2282
2283 if (type >= ARRAY_SIZE(bpf_prog_types))
2284 return -EINVAL;
2285 type = array_index_nospec(type, ARRAY_SIZE(bpf_prog_types));
2286 ops = bpf_prog_types[type];
2287 if (!ops)
2288 return -EINVAL;
2289
2290 if (!bpf_prog_is_offloaded(prog->aux))
2291 prog->aux->ops = ops;
2292 else
2293 prog->aux->ops = &bpf_offload_prog_ops;
2294 prog->type = type;
2295 return 0;
2296 }
2297
2298 enum bpf_audit {
2299 BPF_AUDIT_LOAD,
2300 BPF_AUDIT_UNLOAD,
2301 BPF_AUDIT_MAX,
2302 };
2303
2304 static const char * const bpf_audit_str[BPF_AUDIT_MAX] = {
2305 [BPF_AUDIT_LOAD] = "LOAD",
2306 [BPF_AUDIT_UNLOAD] = "UNLOAD",
2307 };
2308
bpf_audit_prog(const struct bpf_prog * prog,unsigned int op)2309 static void bpf_audit_prog(const struct bpf_prog *prog, unsigned int op)
2310 {
2311 struct audit_context *ctx = NULL;
2312 struct audit_buffer *ab;
2313
2314 if (WARN_ON_ONCE(op >= BPF_AUDIT_MAX))
2315 return;
2316 if (audit_enabled == AUDIT_OFF)
2317 return;
2318 if (!in_hardirq() && !irqs_disabled())
2319 ctx = audit_context();
2320 ab = audit_log_start(ctx, GFP_ATOMIC, AUDIT_BPF);
2321 if (unlikely(!ab))
2322 return;
2323 audit_log_format(ab, "prog-id=%u op=%s",
2324 prog->aux->id, bpf_audit_str[op]);
2325 audit_log_end(ab);
2326 }
2327
bpf_prog_alloc_id(struct bpf_prog * prog)2328 static int bpf_prog_alloc_id(struct bpf_prog *prog)
2329 {
2330 int id;
2331
2332 idr_preload(GFP_KERNEL);
2333 spin_lock_bh(&prog_idr_lock);
2334 id = idr_alloc_cyclic(&prog_idr, prog, 1, INT_MAX, GFP_ATOMIC);
2335 if (id > 0)
2336 prog->aux->id = id;
2337 spin_unlock_bh(&prog_idr_lock);
2338 idr_preload_end();
2339
2340 /* id is in [1, INT_MAX) */
2341 if (WARN_ON_ONCE(!id))
2342 return -ENOSPC;
2343
2344 return id > 0 ? 0 : id;
2345 }
2346
bpf_prog_free_id(struct bpf_prog * prog)2347 void bpf_prog_free_id(struct bpf_prog *prog)
2348 {
2349 unsigned long flags;
2350
2351 /* cBPF to eBPF migrations are currently not in the idr store.
2352 * Offloaded programs are removed from the store when their device
2353 * disappears - even if someone grabs an fd to them they are unusable,
2354 * simply waiting for refcnt to drop to be freed.
2355 */
2356 if (!prog->aux->id)
2357 return;
2358
2359 spin_lock_irqsave(&prog_idr_lock, flags);
2360 idr_remove(&prog_idr, prog->aux->id);
2361 prog->aux->id = 0;
2362 spin_unlock_irqrestore(&prog_idr_lock, flags);
2363 }
2364
__bpf_prog_put_rcu(struct rcu_head * rcu)2365 static void __bpf_prog_put_rcu(struct rcu_head *rcu)
2366 {
2367 struct bpf_prog_aux *aux = container_of(rcu, struct bpf_prog_aux, rcu);
2368
2369 kvfree(aux->func_info);
2370 kfree(aux->func_info_aux);
2371 free_uid(aux->user);
2372 security_bpf_prog_free(aux->prog);
2373 bpf_prog_free(aux->prog);
2374 }
2375
__bpf_prog_put_noref(struct bpf_prog * prog,bool deferred)2376 static void __bpf_prog_put_noref(struct bpf_prog *prog, bool deferred)
2377 {
2378 bpf_prog_kallsyms_del_all(prog);
2379 btf_put(prog->aux->btf);
2380 module_put(prog->aux->mod);
2381 kvfree(prog->aux->jited_linfo);
2382 kvfree(prog->aux->linfo);
2383 kfree(prog->aux->kfunc_tab);
2384 kfree(prog->aux->ctx_arg_info);
2385 if (prog->aux->attach_btf)
2386 btf_put(prog->aux->attach_btf);
2387
2388 if (deferred) {
2389 if (prog->sleepable)
2390 call_rcu_tasks_trace(&prog->aux->rcu, __bpf_prog_put_rcu);
2391 else
2392 call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu);
2393 } else {
2394 __bpf_prog_put_rcu(&prog->aux->rcu);
2395 }
2396 }
2397
bpf_prog_put_deferred(struct work_struct * work)2398 static void bpf_prog_put_deferred(struct work_struct *work)
2399 {
2400 struct bpf_prog_aux *aux;
2401 struct bpf_prog *prog;
2402
2403 aux = container_of(work, struct bpf_prog_aux, work);
2404 prog = aux->prog;
2405 perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_UNLOAD, 0);
2406 bpf_audit_prog(prog, BPF_AUDIT_UNLOAD);
2407 bpf_prog_free_id(prog);
2408 __bpf_prog_put_noref(prog, true);
2409 }
2410
__bpf_prog_put(struct bpf_prog * prog)2411 static void __bpf_prog_put(struct bpf_prog *prog)
2412 {
2413 struct bpf_prog_aux *aux = prog->aux;
2414
2415 if (atomic64_dec_and_test(&aux->refcnt)) {
2416 if (in_hardirq() || irqs_disabled()) {
2417 INIT_WORK(&aux->work, bpf_prog_put_deferred);
2418 schedule_work(&aux->work);
2419 } else {
2420 bpf_prog_put_deferred(&aux->work);
2421 }
2422 }
2423 }
2424
bpf_prog_put(struct bpf_prog * prog)2425 void bpf_prog_put(struct bpf_prog *prog)
2426 {
2427 __bpf_prog_put(prog);
2428 }
2429 EXPORT_SYMBOL_GPL(bpf_prog_put);
2430
bpf_prog_release(struct inode * inode,struct file * filp)2431 static int bpf_prog_release(struct inode *inode, struct file *filp)
2432 {
2433 struct bpf_prog *prog = filp->private_data;
2434
2435 bpf_prog_put(prog);
2436 return 0;
2437 }
2438
2439 struct bpf_prog_kstats {
2440 u64 nsecs;
2441 u64 cnt;
2442 u64 misses;
2443 };
2444
bpf_prog_inc_misses_counter(struct bpf_prog * prog)2445 void notrace bpf_prog_inc_misses_counter(struct bpf_prog *prog)
2446 {
2447 struct bpf_prog_stats *stats;
2448 unsigned int flags;
2449
2450 if (unlikely(!prog->stats))
2451 return;
2452
2453 stats = this_cpu_ptr(prog->stats);
2454 flags = u64_stats_update_begin_irqsave(&stats->syncp);
2455 u64_stats_inc(&stats->misses);
2456 u64_stats_update_end_irqrestore(&stats->syncp, flags);
2457 }
2458
bpf_prog_get_stats(const struct bpf_prog * prog,struct bpf_prog_kstats * stats)2459 static void bpf_prog_get_stats(const struct bpf_prog *prog,
2460 struct bpf_prog_kstats *stats)
2461 {
2462 u64 nsecs = 0, cnt = 0, misses = 0;
2463 int cpu;
2464
2465 for_each_possible_cpu(cpu) {
2466 const struct bpf_prog_stats *st;
2467 unsigned int start;
2468 u64 tnsecs, tcnt, tmisses;
2469
2470 st = per_cpu_ptr(prog->stats, cpu);
2471 do {
2472 start = u64_stats_fetch_begin(&st->syncp);
2473 tnsecs = u64_stats_read(&st->nsecs);
2474 tcnt = u64_stats_read(&st->cnt);
2475 tmisses = u64_stats_read(&st->misses);
2476 } while (u64_stats_fetch_retry(&st->syncp, start));
2477 nsecs += tnsecs;
2478 cnt += tcnt;
2479 misses += tmisses;
2480 }
2481 stats->nsecs = nsecs;
2482 stats->cnt = cnt;
2483 stats->misses = misses;
2484 }
2485
2486 #ifdef CONFIG_PROC_FS
bpf_prog_show_fdinfo(struct seq_file * m,struct file * filp)2487 static void bpf_prog_show_fdinfo(struct seq_file *m, struct file *filp)
2488 {
2489 const struct bpf_prog *prog = filp->private_data;
2490 char prog_tag[sizeof(prog->tag) * 2 + 1] = { };
2491 struct bpf_prog_kstats stats;
2492
2493 bpf_prog_get_stats(prog, &stats);
2494 bin2hex(prog_tag, prog->tag, sizeof(prog->tag));
2495 seq_printf(m,
2496 "prog_type:\t%u\n"
2497 "prog_jited:\t%u\n"
2498 "prog_tag:\t%s\n"
2499 "memlock:\t%llu\n"
2500 "prog_id:\t%u\n"
2501 "run_time_ns:\t%llu\n"
2502 "run_cnt:\t%llu\n"
2503 "recursion_misses:\t%llu\n"
2504 "verified_insns:\t%u\n",
2505 prog->type,
2506 prog->jited,
2507 prog_tag,
2508 prog->pages * 1ULL << PAGE_SHIFT,
2509 prog->aux->id,
2510 stats.nsecs,
2511 stats.cnt,
2512 stats.misses,
2513 prog->aux->verified_insns);
2514 }
2515 #endif
2516
2517 const struct file_operations bpf_prog_fops = {
2518 #ifdef CONFIG_PROC_FS
2519 .show_fdinfo = bpf_prog_show_fdinfo,
2520 #endif
2521 .release = bpf_prog_release,
2522 .read = bpf_dummy_read,
2523 .write = bpf_dummy_write,
2524 };
2525
bpf_prog_new_fd(struct bpf_prog * prog)2526 int bpf_prog_new_fd(struct bpf_prog *prog)
2527 {
2528 int ret;
2529
2530 ret = security_bpf_prog(prog);
2531 if (ret < 0)
2532 return ret;
2533
2534 return anon_inode_getfd("bpf-prog", &bpf_prog_fops, prog,
2535 O_RDWR | O_CLOEXEC);
2536 }
2537
bpf_prog_add(struct bpf_prog * prog,int i)2538 void bpf_prog_add(struct bpf_prog *prog, int i)
2539 {
2540 atomic64_add(i, &prog->aux->refcnt);
2541 }
2542 EXPORT_SYMBOL_GPL(bpf_prog_add);
2543
bpf_prog_sub(struct bpf_prog * prog,int i)2544 void bpf_prog_sub(struct bpf_prog *prog, int i)
2545 {
2546 /* Only to be used for undoing previous bpf_prog_add() in some
2547 * error path. We still know that another entity in our call
2548 * path holds a reference to the program, thus atomic_sub() can
2549 * be safely used in such cases!
2550 */
2551 WARN_ON(atomic64_sub_return(i, &prog->aux->refcnt) == 0);
2552 }
2553 EXPORT_SYMBOL_GPL(bpf_prog_sub);
2554
bpf_prog_inc(struct bpf_prog * prog)2555 void bpf_prog_inc(struct bpf_prog *prog)
2556 {
2557 atomic64_inc(&prog->aux->refcnt);
2558 }
2559 EXPORT_SYMBOL_GPL(bpf_prog_inc);
2560
2561 /* prog_idr_lock should have been held */
bpf_prog_inc_not_zero(struct bpf_prog * prog)2562 struct bpf_prog *bpf_prog_inc_not_zero(struct bpf_prog *prog)
2563 {
2564 int refold;
2565
2566 refold = atomic64_fetch_add_unless(&prog->aux->refcnt, 1, 0);
2567
2568 if (!refold)
2569 return ERR_PTR(-ENOENT);
2570
2571 return prog;
2572 }
2573 EXPORT_SYMBOL_GPL(bpf_prog_inc_not_zero);
2574
bpf_prog_get_ok(struct bpf_prog * prog,enum bpf_prog_type * attach_type,bool attach_drv)2575 bool bpf_prog_get_ok(struct bpf_prog *prog,
2576 enum bpf_prog_type *attach_type, bool attach_drv)
2577 {
2578 /* not an attachment, just a refcount inc, always allow */
2579 if (!attach_type)
2580 return true;
2581
2582 if (prog->type != *attach_type)
2583 return false;
2584 if (bpf_prog_is_offloaded(prog->aux) && !attach_drv)
2585 return false;
2586
2587 return true;
2588 }
2589
__bpf_prog_get(u32 ufd,enum bpf_prog_type * attach_type,bool attach_drv)2590 static struct bpf_prog *__bpf_prog_get(u32 ufd, enum bpf_prog_type *attach_type,
2591 bool attach_drv)
2592 {
2593 CLASS(fd, f)(ufd);
2594 struct bpf_prog *prog;
2595
2596 if (fd_empty(f))
2597 return ERR_PTR(-EBADF);
2598 if (fd_file(f)->f_op != &bpf_prog_fops)
2599 return ERR_PTR(-EINVAL);
2600
2601 prog = fd_file(f)->private_data;
2602 if (!bpf_prog_get_ok(prog, attach_type, attach_drv))
2603 return ERR_PTR(-EINVAL);
2604
2605 bpf_prog_inc(prog);
2606 return prog;
2607 }
2608
bpf_prog_get(u32 ufd)2609 struct bpf_prog *bpf_prog_get(u32 ufd)
2610 {
2611 return __bpf_prog_get(ufd, NULL, false);
2612 }
2613
bpf_prog_get_type_dev(u32 ufd,enum bpf_prog_type type,bool attach_drv)2614 struct bpf_prog *bpf_prog_get_type_dev(u32 ufd, enum bpf_prog_type type,
2615 bool attach_drv)
2616 {
2617 return __bpf_prog_get(ufd, &type, attach_drv);
2618 }
2619 EXPORT_SYMBOL_GPL(bpf_prog_get_type_dev);
2620
2621 /* Initially all BPF programs could be loaded w/o specifying
2622 * expected_attach_type. Later for some of them specifying expected_attach_type
2623 * at load time became required so that program could be validated properly.
2624 * Programs of types that are allowed to be loaded both w/ and w/o (for
2625 * backward compatibility) expected_attach_type, should have the default attach
2626 * type assigned to expected_attach_type for the latter case, so that it can be
2627 * validated later at attach time.
2628 *
2629 * bpf_prog_load_fixup_attach_type() sets expected_attach_type in @attr if
2630 * prog type requires it but has some attach types that have to be backward
2631 * compatible.
2632 */
bpf_prog_load_fixup_attach_type(union bpf_attr * attr)2633 static void bpf_prog_load_fixup_attach_type(union bpf_attr *attr)
2634 {
2635 switch (attr->prog_type) {
2636 case BPF_PROG_TYPE_CGROUP_SOCK:
2637 /* Unfortunately BPF_ATTACH_TYPE_UNSPEC enumeration doesn't
2638 * exist so checking for non-zero is the way to go here.
2639 */
2640 if (!attr->expected_attach_type)
2641 attr->expected_attach_type =
2642 BPF_CGROUP_INET_SOCK_CREATE;
2643 break;
2644 case BPF_PROG_TYPE_SK_REUSEPORT:
2645 if (!attr->expected_attach_type)
2646 attr->expected_attach_type =
2647 BPF_SK_REUSEPORT_SELECT;
2648 break;
2649 }
2650 }
2651
2652 static int
bpf_prog_load_check_attach(enum bpf_prog_type prog_type,enum bpf_attach_type expected_attach_type,struct btf * attach_btf,u32 btf_id,struct bpf_prog * dst_prog)2653 bpf_prog_load_check_attach(enum bpf_prog_type prog_type,
2654 enum bpf_attach_type expected_attach_type,
2655 struct btf *attach_btf, u32 btf_id,
2656 struct bpf_prog *dst_prog)
2657 {
2658 if (btf_id) {
2659 if (btf_id > BTF_MAX_TYPE)
2660 return -EINVAL;
2661
2662 if (!attach_btf && !dst_prog)
2663 return -EINVAL;
2664
2665 switch (prog_type) {
2666 case BPF_PROG_TYPE_TRACING:
2667 case BPF_PROG_TYPE_LSM:
2668 case BPF_PROG_TYPE_STRUCT_OPS:
2669 case BPF_PROG_TYPE_EXT:
2670 break;
2671 default:
2672 return -EINVAL;
2673 }
2674 }
2675
2676 if (attach_btf && (!btf_id || dst_prog))
2677 return -EINVAL;
2678
2679 if (dst_prog && prog_type != BPF_PROG_TYPE_TRACING &&
2680 prog_type != BPF_PROG_TYPE_EXT)
2681 return -EINVAL;
2682
2683 switch (prog_type) {
2684 case BPF_PROG_TYPE_CGROUP_SOCK:
2685 switch (expected_attach_type) {
2686 case BPF_CGROUP_INET_SOCK_CREATE:
2687 case BPF_CGROUP_INET_SOCK_RELEASE:
2688 case BPF_CGROUP_INET4_POST_BIND:
2689 case BPF_CGROUP_INET6_POST_BIND:
2690 return 0;
2691 default:
2692 return -EINVAL;
2693 }
2694 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
2695 switch (expected_attach_type) {
2696 case BPF_CGROUP_INET4_BIND:
2697 case BPF_CGROUP_INET6_BIND:
2698 case BPF_CGROUP_INET4_CONNECT:
2699 case BPF_CGROUP_INET6_CONNECT:
2700 case BPF_CGROUP_UNIX_CONNECT:
2701 case BPF_CGROUP_INET4_GETPEERNAME:
2702 case BPF_CGROUP_INET6_GETPEERNAME:
2703 case BPF_CGROUP_UNIX_GETPEERNAME:
2704 case BPF_CGROUP_INET4_GETSOCKNAME:
2705 case BPF_CGROUP_INET6_GETSOCKNAME:
2706 case BPF_CGROUP_UNIX_GETSOCKNAME:
2707 case BPF_CGROUP_UDP4_SENDMSG:
2708 case BPF_CGROUP_UDP6_SENDMSG:
2709 case BPF_CGROUP_UNIX_SENDMSG:
2710 case BPF_CGROUP_UDP4_RECVMSG:
2711 case BPF_CGROUP_UDP6_RECVMSG:
2712 case BPF_CGROUP_UNIX_RECVMSG:
2713 return 0;
2714 default:
2715 return -EINVAL;
2716 }
2717 case BPF_PROG_TYPE_CGROUP_SKB:
2718 switch (expected_attach_type) {
2719 case BPF_CGROUP_INET_INGRESS:
2720 case BPF_CGROUP_INET_EGRESS:
2721 return 0;
2722 default:
2723 return -EINVAL;
2724 }
2725 case BPF_PROG_TYPE_CGROUP_SOCKOPT:
2726 switch (expected_attach_type) {
2727 case BPF_CGROUP_SETSOCKOPT:
2728 case BPF_CGROUP_GETSOCKOPT:
2729 return 0;
2730 default:
2731 return -EINVAL;
2732 }
2733 case BPF_PROG_TYPE_SK_LOOKUP:
2734 if (expected_attach_type == BPF_SK_LOOKUP)
2735 return 0;
2736 return -EINVAL;
2737 case BPF_PROG_TYPE_SK_REUSEPORT:
2738 switch (expected_attach_type) {
2739 case BPF_SK_REUSEPORT_SELECT:
2740 case BPF_SK_REUSEPORT_SELECT_OR_MIGRATE:
2741 return 0;
2742 default:
2743 return -EINVAL;
2744 }
2745 case BPF_PROG_TYPE_NETFILTER:
2746 if (expected_attach_type == BPF_NETFILTER)
2747 return 0;
2748 return -EINVAL;
2749 case BPF_PROG_TYPE_SYSCALL:
2750 case BPF_PROG_TYPE_EXT:
2751 if (expected_attach_type)
2752 return -EINVAL;
2753 fallthrough;
2754 default:
2755 return 0;
2756 }
2757 }
2758
is_net_admin_prog_type(enum bpf_prog_type prog_type)2759 static bool is_net_admin_prog_type(enum bpf_prog_type prog_type)
2760 {
2761 switch (prog_type) {
2762 case BPF_PROG_TYPE_SCHED_CLS:
2763 case BPF_PROG_TYPE_SCHED_ACT:
2764 case BPF_PROG_TYPE_XDP:
2765 case BPF_PROG_TYPE_LWT_IN:
2766 case BPF_PROG_TYPE_LWT_OUT:
2767 case BPF_PROG_TYPE_LWT_XMIT:
2768 case BPF_PROG_TYPE_LWT_SEG6LOCAL:
2769 case BPF_PROG_TYPE_SK_SKB:
2770 case BPF_PROG_TYPE_SK_MSG:
2771 case BPF_PROG_TYPE_FLOW_DISSECTOR:
2772 case BPF_PROG_TYPE_CGROUP_DEVICE:
2773 case BPF_PROG_TYPE_CGROUP_SOCK:
2774 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
2775 case BPF_PROG_TYPE_CGROUP_SOCKOPT:
2776 case BPF_PROG_TYPE_CGROUP_SYSCTL:
2777 case BPF_PROG_TYPE_SOCK_OPS:
2778 case BPF_PROG_TYPE_EXT: /* extends any prog */
2779 case BPF_PROG_TYPE_NETFILTER:
2780 return true;
2781 case BPF_PROG_TYPE_CGROUP_SKB:
2782 /* always unpriv */
2783 case BPF_PROG_TYPE_SK_REUSEPORT:
2784 /* equivalent to SOCKET_FILTER. need CAP_BPF only */
2785 default:
2786 return false;
2787 }
2788 }
2789
is_perfmon_prog_type(enum bpf_prog_type prog_type)2790 static bool is_perfmon_prog_type(enum bpf_prog_type prog_type)
2791 {
2792 switch (prog_type) {
2793 case BPF_PROG_TYPE_KPROBE:
2794 case BPF_PROG_TYPE_TRACEPOINT:
2795 case BPF_PROG_TYPE_PERF_EVENT:
2796 case BPF_PROG_TYPE_RAW_TRACEPOINT:
2797 case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE:
2798 case BPF_PROG_TYPE_TRACING:
2799 case BPF_PROG_TYPE_LSM:
2800 case BPF_PROG_TYPE_STRUCT_OPS: /* has access to struct sock */
2801 case BPF_PROG_TYPE_EXT: /* extends any prog */
2802 return true;
2803 default:
2804 return false;
2805 }
2806 }
2807
bpf_prog_verify_signature(struct bpf_prog * prog,union bpf_attr * attr,bool is_kernel)2808 static int bpf_prog_verify_signature(struct bpf_prog *prog, union bpf_attr *attr,
2809 bool is_kernel)
2810 {
2811 bpfptr_t usig = make_bpfptr(attr->signature, is_kernel);
2812 struct bpf_dynptr_kern sig_ptr, insns_ptr;
2813 struct bpf_key *key = NULL;
2814 void *sig;
2815 int err = 0;
2816
2817 /*
2818 * Don't attempt to use kmalloc_large or vmalloc for signatures.
2819 * Practical signature for BPF program should be below this limit.
2820 */
2821 if (attr->signature_size > KMALLOC_MAX_CACHE_SIZE)
2822 return -EINVAL;
2823
2824 if (system_keyring_id_check(attr->keyring_id) == 0)
2825 key = bpf_lookup_system_key(attr->keyring_id);
2826 else
2827 key = bpf_lookup_user_key(attr->keyring_id, 0);
2828
2829 if (!key)
2830 return -EINVAL;
2831
2832 sig = kvmemdup_bpfptr(usig, attr->signature_size);
2833 if (IS_ERR(sig)) {
2834 bpf_key_put(key);
2835 return -ENOMEM;
2836 }
2837
2838 bpf_dynptr_init(&sig_ptr, sig, BPF_DYNPTR_TYPE_LOCAL, 0,
2839 attr->signature_size);
2840 bpf_dynptr_init(&insns_ptr, prog->insnsi, BPF_DYNPTR_TYPE_LOCAL, 0,
2841 prog->len * sizeof(struct bpf_insn));
2842
2843 err = bpf_verify_pkcs7_signature((struct bpf_dynptr *)&insns_ptr,
2844 (struct bpf_dynptr *)&sig_ptr, key);
2845
2846 bpf_key_put(key);
2847 kvfree(sig);
2848 return err;
2849 }
2850
bpf_prog_mark_insn_arrays_ready(struct bpf_prog * prog)2851 static int bpf_prog_mark_insn_arrays_ready(struct bpf_prog *prog)
2852 {
2853 int err;
2854 int i;
2855
2856 for (i = 0; i < prog->aux->used_map_cnt; i++) {
2857 if (prog->aux->used_maps[i]->map_type != BPF_MAP_TYPE_INSN_ARRAY)
2858 continue;
2859
2860 err = bpf_insn_array_ready(prog->aux->used_maps[i]);
2861 if (err)
2862 return err;
2863 }
2864
2865 return 0;
2866 }
2867
2868 /* last field in 'union bpf_attr' used by this command */
2869 #define BPF_PROG_LOAD_LAST_FIELD keyring_id
2870
bpf_prog_load(union bpf_attr * attr,bpfptr_t uattr,u32 uattr_size)2871 static int bpf_prog_load(union bpf_attr *attr, bpfptr_t uattr, u32 uattr_size)
2872 {
2873 enum bpf_prog_type type = attr->prog_type;
2874 struct bpf_prog *prog, *dst_prog = NULL;
2875 struct btf *attach_btf = NULL;
2876 struct bpf_token *token = NULL;
2877 bool bpf_cap;
2878 int err;
2879 char license[128];
2880
2881 if (CHECK_ATTR(BPF_PROG_LOAD))
2882 return -EINVAL;
2883
2884 if (attr->prog_flags & ~(BPF_F_STRICT_ALIGNMENT |
2885 BPF_F_ANY_ALIGNMENT |
2886 BPF_F_TEST_STATE_FREQ |
2887 BPF_F_SLEEPABLE |
2888 BPF_F_TEST_RND_HI32 |
2889 BPF_F_XDP_HAS_FRAGS |
2890 BPF_F_XDP_DEV_BOUND_ONLY |
2891 BPF_F_TEST_REG_INVARIANTS |
2892 BPF_F_TOKEN_FD))
2893 return -EINVAL;
2894
2895 bpf_prog_load_fixup_attach_type(attr);
2896
2897 if (attr->prog_flags & BPF_F_TOKEN_FD) {
2898 token = bpf_token_get_from_fd(attr->prog_token_fd);
2899 if (IS_ERR(token))
2900 return PTR_ERR(token);
2901 /* if current token doesn't grant prog loading permissions,
2902 * then we can't use this token, so ignore it and rely on
2903 * system-wide capabilities checks
2904 */
2905 if (!bpf_token_allow_cmd(token, BPF_PROG_LOAD) ||
2906 !bpf_token_allow_prog_type(token, attr->prog_type,
2907 attr->expected_attach_type)) {
2908 bpf_token_put(token);
2909 token = NULL;
2910 }
2911 }
2912
2913 bpf_cap = bpf_token_capable(token, CAP_BPF);
2914 err = -EPERM;
2915
2916 if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) &&
2917 (attr->prog_flags & BPF_F_ANY_ALIGNMENT) &&
2918 !bpf_cap)
2919 goto put_token;
2920
2921 /* Intent here is for unprivileged_bpf_disabled to block BPF program
2922 * creation for unprivileged users; other actions depend
2923 * on fd availability and access to bpffs, so are dependent on
2924 * object creation success. Even with unprivileged BPF disabled,
2925 * capability checks are still carried out for these
2926 * and other operations.
2927 */
2928 if (sysctl_unprivileged_bpf_disabled && !bpf_cap)
2929 goto put_token;
2930
2931 if (attr->insn_cnt == 0 ||
2932 attr->insn_cnt > (bpf_cap ? BPF_COMPLEXITY_LIMIT_INSNS : BPF_MAXINSNS)) {
2933 err = -E2BIG;
2934 goto put_token;
2935 }
2936 if (type != BPF_PROG_TYPE_SOCKET_FILTER &&
2937 type != BPF_PROG_TYPE_CGROUP_SKB &&
2938 !bpf_cap)
2939 goto put_token;
2940
2941 if (is_net_admin_prog_type(type) && !bpf_token_capable(token, CAP_NET_ADMIN))
2942 goto put_token;
2943 if (is_perfmon_prog_type(type) && !bpf_token_capable(token, CAP_PERFMON))
2944 goto put_token;
2945
2946 /* attach_prog_fd/attach_btf_obj_fd can specify fd of either bpf_prog
2947 * or btf, we need to check which one it is
2948 */
2949 if (attr->attach_prog_fd) {
2950 dst_prog = bpf_prog_get(attr->attach_prog_fd);
2951 if (IS_ERR(dst_prog)) {
2952 dst_prog = NULL;
2953 attach_btf = btf_get_by_fd(attr->attach_btf_obj_fd);
2954 if (IS_ERR(attach_btf)) {
2955 err = -EINVAL;
2956 goto put_token;
2957 }
2958 if (!btf_is_kernel(attach_btf)) {
2959 /* attaching through specifying bpf_prog's BTF
2960 * objects directly might be supported eventually
2961 */
2962 btf_put(attach_btf);
2963 err = -ENOTSUPP;
2964 goto put_token;
2965 }
2966 }
2967 } else if (attr->attach_btf_id) {
2968 /* fall back to vmlinux BTF, if BTF type ID is specified */
2969 attach_btf = bpf_get_btf_vmlinux();
2970 if (IS_ERR(attach_btf)) {
2971 err = PTR_ERR(attach_btf);
2972 goto put_token;
2973 }
2974 if (!attach_btf) {
2975 err = -EINVAL;
2976 goto put_token;
2977 }
2978 btf_get(attach_btf);
2979 }
2980
2981 if (bpf_prog_load_check_attach(type, attr->expected_attach_type,
2982 attach_btf, attr->attach_btf_id,
2983 dst_prog)) {
2984 if (dst_prog)
2985 bpf_prog_put(dst_prog);
2986 if (attach_btf)
2987 btf_put(attach_btf);
2988 err = -EINVAL;
2989 goto put_token;
2990 }
2991
2992 /* plain bpf_prog allocation */
2993 prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER);
2994 if (!prog) {
2995 if (dst_prog)
2996 bpf_prog_put(dst_prog);
2997 if (attach_btf)
2998 btf_put(attach_btf);
2999 err = -EINVAL;
3000 goto put_token;
3001 }
3002
3003 prog->expected_attach_type = attr->expected_attach_type;
3004 prog->sleepable = !!(attr->prog_flags & BPF_F_SLEEPABLE);
3005 prog->aux->attach_btf = attach_btf;
3006 prog->aux->attach_btf_id = attr->attach_btf_id;
3007 prog->aux->dst_prog = dst_prog;
3008 prog->aux->dev_bound = !!attr->prog_ifindex;
3009 prog->aux->xdp_has_frags = attr->prog_flags & BPF_F_XDP_HAS_FRAGS;
3010
3011 /* move token into prog->aux, reuse taken refcnt */
3012 prog->aux->token = token;
3013 token = NULL;
3014
3015 prog->aux->user = get_current_user();
3016 prog->len = attr->insn_cnt;
3017
3018 err = -EFAULT;
3019 if (copy_from_bpfptr(prog->insns,
3020 make_bpfptr(attr->insns, uattr.is_kernel),
3021 bpf_prog_insn_size(prog)) != 0)
3022 goto free_prog;
3023 /* copy eBPF program license from user space */
3024 if (strncpy_from_bpfptr(license,
3025 make_bpfptr(attr->license, uattr.is_kernel),
3026 sizeof(license) - 1) < 0)
3027 goto free_prog;
3028 license[sizeof(license) - 1] = 0;
3029
3030 /* eBPF programs must be GPL compatible to use GPL-ed functions */
3031 prog->gpl_compatible = license_is_gpl_compatible(license) ? 1 : 0;
3032
3033 if (attr->signature) {
3034 err = bpf_prog_verify_signature(prog, attr, uattr.is_kernel);
3035 if (err)
3036 goto free_prog;
3037 }
3038
3039 prog->orig_prog = NULL;
3040 prog->jited = 0;
3041
3042 atomic64_set(&prog->aux->refcnt, 1);
3043
3044 if (bpf_prog_is_dev_bound(prog->aux)) {
3045 err = bpf_prog_dev_bound_init(prog, attr);
3046 if (err)
3047 goto free_prog;
3048 }
3049
3050 if (type == BPF_PROG_TYPE_EXT && dst_prog &&
3051 bpf_prog_is_dev_bound(dst_prog->aux)) {
3052 err = bpf_prog_dev_bound_inherit(prog, dst_prog);
3053 if (err)
3054 goto free_prog;
3055 }
3056
3057 /*
3058 * Bookkeeping for managing the program attachment chain.
3059 *
3060 * It might be tempting to set attach_tracing_prog flag at the attachment
3061 * time, but this will not prevent from loading bunch of tracing prog
3062 * first, then attach them one to another.
3063 *
3064 * The flag attach_tracing_prog is set for the whole program lifecycle, and
3065 * doesn't have to be cleared in bpf_tracing_link_release, since tracing
3066 * programs cannot change attachment target.
3067 */
3068 if (type == BPF_PROG_TYPE_TRACING && dst_prog &&
3069 dst_prog->type == BPF_PROG_TYPE_TRACING) {
3070 prog->aux->attach_tracing_prog = true;
3071 }
3072
3073 /* find program type: socket_filter vs tracing_filter */
3074 err = find_prog_type(type, prog);
3075 if (err < 0)
3076 goto free_prog;
3077
3078 prog->aux->load_time = ktime_get_boottime_ns();
3079 err = bpf_obj_name_cpy(prog->aux->name, attr->prog_name,
3080 sizeof(attr->prog_name));
3081 if (err < 0)
3082 goto free_prog;
3083
3084 err = security_bpf_prog_load(prog, attr, token, uattr.is_kernel);
3085 if (err)
3086 goto free_prog_sec;
3087
3088 /* run eBPF verifier */
3089 err = bpf_check(&prog, attr, uattr, uattr_size);
3090 if (err < 0)
3091 goto free_used_maps;
3092
3093 prog = bpf_prog_select_runtime(prog, &err);
3094 if (err < 0)
3095 goto free_used_maps;
3096
3097 err = bpf_prog_mark_insn_arrays_ready(prog);
3098 if (err < 0)
3099 goto free_used_maps;
3100
3101 err = bpf_prog_alloc_id(prog);
3102 if (err)
3103 goto free_used_maps;
3104
3105 /* Upon success of bpf_prog_alloc_id(), the BPF prog is
3106 * effectively publicly exposed. However, retrieving via
3107 * bpf_prog_get_fd_by_id() will take another reference,
3108 * therefore it cannot be gone underneath us.
3109 *
3110 * Only for the time /after/ successful bpf_prog_new_fd()
3111 * and before returning to userspace, we might just hold
3112 * one reference and any parallel close on that fd could
3113 * rip everything out. Hence, below notifications must
3114 * happen before bpf_prog_new_fd().
3115 *
3116 * Also, any failure handling from this point onwards must
3117 * be using bpf_prog_put() given the program is exposed.
3118 */
3119 bpf_prog_kallsyms_add(prog);
3120 perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_LOAD, 0);
3121 bpf_audit_prog(prog, BPF_AUDIT_LOAD);
3122
3123 err = bpf_prog_new_fd(prog);
3124 if (err < 0)
3125 bpf_prog_put(prog);
3126 return err;
3127
3128 free_used_maps:
3129 /* In case we have subprogs, we need to wait for a grace
3130 * period before we can tear down JIT memory since symbols
3131 * are already exposed under kallsyms.
3132 */
3133 __bpf_prog_put_noref(prog, prog->aux->real_func_cnt);
3134 return err;
3135
3136 free_prog_sec:
3137 security_bpf_prog_free(prog);
3138 free_prog:
3139 free_uid(prog->aux->user);
3140 if (prog->aux->attach_btf)
3141 btf_put(prog->aux->attach_btf);
3142 bpf_prog_free(prog);
3143 put_token:
3144 bpf_token_put(token);
3145 return err;
3146 }
3147
3148 #define BPF_OBJ_LAST_FIELD path_fd
3149
bpf_obj_pin(const union bpf_attr * attr)3150 static int bpf_obj_pin(const union bpf_attr *attr)
3151 {
3152 int path_fd;
3153
3154 if (CHECK_ATTR(BPF_OBJ) || attr->file_flags & ~BPF_F_PATH_FD)
3155 return -EINVAL;
3156
3157 /* path_fd has to be accompanied by BPF_F_PATH_FD flag */
3158 if (!(attr->file_flags & BPF_F_PATH_FD) && attr->path_fd)
3159 return -EINVAL;
3160
3161 path_fd = attr->file_flags & BPF_F_PATH_FD ? attr->path_fd : AT_FDCWD;
3162 return bpf_obj_pin_user(attr->bpf_fd, path_fd,
3163 u64_to_user_ptr(attr->pathname));
3164 }
3165
bpf_obj_get(const union bpf_attr * attr)3166 static int bpf_obj_get(const union bpf_attr *attr)
3167 {
3168 int path_fd;
3169
3170 if (CHECK_ATTR(BPF_OBJ) || attr->bpf_fd != 0 ||
3171 attr->file_flags & ~(BPF_OBJ_FLAG_MASK | BPF_F_PATH_FD))
3172 return -EINVAL;
3173
3174 /* path_fd has to be accompanied by BPF_F_PATH_FD flag */
3175 if (!(attr->file_flags & BPF_F_PATH_FD) && attr->path_fd)
3176 return -EINVAL;
3177
3178 path_fd = attr->file_flags & BPF_F_PATH_FD ? attr->path_fd : AT_FDCWD;
3179 return bpf_obj_get_user(path_fd, u64_to_user_ptr(attr->pathname),
3180 attr->file_flags);
3181 }
3182
3183 /* bpf_link_init_sleepable() allows to specify whether BPF link itself has
3184 * "sleepable" semantics, which normally would mean that BPF link's attach
3185 * hook can dereference link or link's underlying program for some time after
3186 * detachment due to RCU Tasks Trace-based lifetime protection scheme.
3187 * BPF program itself can be non-sleepable, yet, because it's transitively
3188 * reachable through BPF link, its freeing has to be delayed until after RCU
3189 * Tasks Trace GP.
3190 */
bpf_link_init_sleepable(struct bpf_link * link,enum bpf_link_type type,const struct bpf_link_ops * ops,struct bpf_prog * prog,enum bpf_attach_type attach_type,bool sleepable)3191 void bpf_link_init_sleepable(struct bpf_link *link, enum bpf_link_type type,
3192 const struct bpf_link_ops *ops, struct bpf_prog *prog,
3193 enum bpf_attach_type attach_type, bool sleepable)
3194 {
3195 WARN_ON(ops->dealloc && ops->dealloc_deferred);
3196 atomic64_set(&link->refcnt, 1);
3197 link->type = type;
3198 link->sleepable = sleepable;
3199 link->id = 0;
3200 link->ops = ops;
3201 link->prog = prog;
3202 link->attach_type = attach_type;
3203 }
3204
bpf_link_init(struct bpf_link * link,enum bpf_link_type type,const struct bpf_link_ops * ops,struct bpf_prog * prog,enum bpf_attach_type attach_type)3205 void bpf_link_init(struct bpf_link *link, enum bpf_link_type type,
3206 const struct bpf_link_ops *ops, struct bpf_prog *prog,
3207 enum bpf_attach_type attach_type)
3208 {
3209 bpf_link_init_sleepable(link, type, ops, prog, attach_type, false);
3210 }
3211
bpf_link_free_id(int id)3212 static void bpf_link_free_id(int id)
3213 {
3214 if (!id)
3215 return;
3216
3217 spin_lock_bh(&link_idr_lock);
3218 idr_remove(&link_idr, id);
3219 spin_unlock_bh(&link_idr_lock);
3220 }
3221
3222 /* Clean up bpf_link and corresponding anon_inode file and FD. After
3223 * anon_inode is created, bpf_link can't be just kfree()'d due to deferred
3224 * anon_inode's release() call. This helper marks bpf_link as
3225 * defunct, releases anon_inode file and puts reserved FD. bpf_prog's refcnt
3226 * is not decremented, it's the responsibility of a calling code that failed
3227 * to complete bpf_link initialization.
3228 * This helper eventually calls link's dealloc callback, but does not call
3229 * link's release callback.
3230 */
bpf_link_cleanup(struct bpf_link_primer * primer)3231 void bpf_link_cleanup(struct bpf_link_primer *primer)
3232 {
3233 primer->link->prog = NULL;
3234 bpf_link_free_id(primer->id);
3235 fput(primer->file);
3236 put_unused_fd(primer->fd);
3237 }
3238
bpf_link_inc(struct bpf_link * link)3239 void bpf_link_inc(struct bpf_link *link)
3240 {
3241 atomic64_inc(&link->refcnt);
3242 }
3243
bpf_link_dealloc(struct bpf_link * link)3244 static void bpf_link_dealloc(struct bpf_link *link)
3245 {
3246 /* now that we know that bpf_link itself can't be reached, put underlying BPF program */
3247 if (link->prog)
3248 bpf_prog_put(link->prog);
3249
3250 /* free bpf_link and its containing memory */
3251 if (link->ops->dealloc_deferred)
3252 link->ops->dealloc_deferred(link);
3253 else
3254 link->ops->dealloc(link);
3255 }
3256
bpf_link_defer_dealloc_rcu_gp(struct rcu_head * rcu)3257 static void bpf_link_defer_dealloc_rcu_gp(struct rcu_head *rcu)
3258 {
3259 struct bpf_link *link = container_of(rcu, struct bpf_link, rcu);
3260
3261 bpf_link_dealloc(link);
3262 }
3263
bpf_link_defer_dealloc_mult_rcu_gp(struct rcu_head * rcu)3264 static void bpf_link_defer_dealloc_mult_rcu_gp(struct rcu_head *rcu)
3265 {
3266 if (rcu_trace_implies_rcu_gp())
3267 bpf_link_defer_dealloc_rcu_gp(rcu);
3268 else
3269 call_rcu(rcu, bpf_link_defer_dealloc_rcu_gp);
3270 }
3271
3272 /* bpf_link_free is guaranteed to be called from process context */
bpf_link_free(struct bpf_link * link)3273 static void bpf_link_free(struct bpf_link *link)
3274 {
3275 const struct bpf_link_ops *ops = link->ops;
3276
3277 bpf_link_free_id(link->id);
3278 /* detach BPF program, clean up used resources */
3279 if (link->prog)
3280 ops->release(link);
3281 if (ops->dealloc_deferred) {
3282 /* Schedule BPF link deallocation, which will only then
3283 * trigger putting BPF program refcount.
3284 * If underlying BPF program is sleepable or BPF link's target
3285 * attach hookpoint is sleepable or otherwise requires RCU GPs
3286 * to ensure link and its underlying BPF program is not
3287 * reachable anymore, we need to first wait for RCU tasks
3288 * trace sync, and then go through "classic" RCU grace period
3289 */
3290 if (link->sleepable || (link->prog && link->prog->sleepable))
3291 call_rcu_tasks_trace(&link->rcu, bpf_link_defer_dealloc_mult_rcu_gp);
3292 else
3293 call_rcu(&link->rcu, bpf_link_defer_dealloc_rcu_gp);
3294 } else if (ops->dealloc) {
3295 bpf_link_dealloc(link);
3296 }
3297 }
3298
bpf_link_put_deferred(struct work_struct * work)3299 static void bpf_link_put_deferred(struct work_struct *work)
3300 {
3301 struct bpf_link *link = container_of(work, struct bpf_link, work);
3302
3303 bpf_link_free(link);
3304 }
3305
3306 /* bpf_link_put might be called from atomic context. It needs to be called
3307 * from sleepable context in order to acquire sleeping locks during the process.
3308 */
bpf_link_put(struct bpf_link * link)3309 void bpf_link_put(struct bpf_link *link)
3310 {
3311 if (!atomic64_dec_and_test(&link->refcnt))
3312 return;
3313
3314 INIT_WORK(&link->work, bpf_link_put_deferred);
3315 schedule_work(&link->work);
3316 }
3317 EXPORT_SYMBOL(bpf_link_put);
3318
bpf_link_put_direct(struct bpf_link * link)3319 static void bpf_link_put_direct(struct bpf_link *link)
3320 {
3321 if (!atomic64_dec_and_test(&link->refcnt))
3322 return;
3323 bpf_link_free(link);
3324 }
3325
bpf_link_release(struct inode * inode,struct file * filp)3326 static int bpf_link_release(struct inode *inode, struct file *filp)
3327 {
3328 struct bpf_link *link = filp->private_data;
3329
3330 bpf_link_put_direct(link);
3331 return 0;
3332 }
3333
3334 #ifdef CONFIG_PROC_FS
3335 #define BPF_PROG_TYPE(_id, _name, prog_ctx_type, kern_ctx_type)
3336 #define BPF_MAP_TYPE(_id, _ops)
3337 #define BPF_LINK_TYPE(_id, _name) [_id] = #_name,
3338 static const char *bpf_link_type_strs[] = {
3339 [BPF_LINK_TYPE_UNSPEC] = "<invalid>",
3340 #include <linux/bpf_types.h>
3341 };
3342 #undef BPF_PROG_TYPE
3343 #undef BPF_MAP_TYPE
3344 #undef BPF_LINK_TYPE
3345
bpf_link_show_fdinfo(struct seq_file * m,struct file * filp)3346 static void bpf_link_show_fdinfo(struct seq_file *m, struct file *filp)
3347 {
3348 const struct bpf_link *link = filp->private_data;
3349 const struct bpf_prog *prog = link->prog;
3350 enum bpf_link_type type = link->type;
3351 char prog_tag[sizeof(prog->tag) * 2 + 1] = { };
3352
3353 if (type < ARRAY_SIZE(bpf_link_type_strs) && bpf_link_type_strs[type]) {
3354 if (link->type == BPF_LINK_TYPE_KPROBE_MULTI)
3355 seq_printf(m, "link_type:\t%s\n", link->flags == BPF_F_KPROBE_MULTI_RETURN ?
3356 "kretprobe_multi" : "kprobe_multi");
3357 else if (link->type == BPF_LINK_TYPE_UPROBE_MULTI)
3358 seq_printf(m, "link_type:\t%s\n", link->flags == BPF_F_UPROBE_MULTI_RETURN ?
3359 "uretprobe_multi" : "uprobe_multi");
3360 else
3361 seq_printf(m, "link_type:\t%s\n", bpf_link_type_strs[type]);
3362 } else {
3363 WARN_ONCE(1, "missing BPF_LINK_TYPE(...) for link type %u\n", type);
3364 seq_printf(m, "link_type:\t<%u>\n", type);
3365 }
3366 seq_printf(m, "link_id:\t%u\n", link->id);
3367
3368 if (prog) {
3369 bin2hex(prog_tag, prog->tag, sizeof(prog->tag));
3370 seq_printf(m,
3371 "prog_tag:\t%s\n"
3372 "prog_id:\t%u\n",
3373 prog_tag,
3374 prog->aux->id);
3375 }
3376 if (link->ops->show_fdinfo)
3377 link->ops->show_fdinfo(link, m);
3378 }
3379 #endif
3380
bpf_link_poll(struct file * file,struct poll_table_struct * pts)3381 static __poll_t bpf_link_poll(struct file *file, struct poll_table_struct *pts)
3382 {
3383 struct bpf_link *link = file->private_data;
3384
3385 return link->ops->poll(file, pts);
3386 }
3387
3388 static const struct file_operations bpf_link_fops = {
3389 #ifdef CONFIG_PROC_FS
3390 .show_fdinfo = bpf_link_show_fdinfo,
3391 #endif
3392 .release = bpf_link_release,
3393 .read = bpf_dummy_read,
3394 .write = bpf_dummy_write,
3395 };
3396
3397 static const struct file_operations bpf_link_fops_poll = {
3398 #ifdef CONFIG_PROC_FS
3399 .show_fdinfo = bpf_link_show_fdinfo,
3400 #endif
3401 .release = bpf_link_release,
3402 .read = bpf_dummy_read,
3403 .write = bpf_dummy_write,
3404 .poll = bpf_link_poll,
3405 };
3406
bpf_link_alloc_id(struct bpf_link * link)3407 static int bpf_link_alloc_id(struct bpf_link *link)
3408 {
3409 int id;
3410
3411 idr_preload(GFP_KERNEL);
3412 spin_lock_bh(&link_idr_lock);
3413 id = idr_alloc_cyclic(&link_idr, link, 1, INT_MAX, GFP_ATOMIC);
3414 spin_unlock_bh(&link_idr_lock);
3415 idr_preload_end();
3416
3417 return id;
3418 }
3419
3420 /* Prepare bpf_link to be exposed to user-space by allocating anon_inode file,
3421 * reserving unused FD and allocating ID from link_idr. This is to be paired
3422 * with bpf_link_settle() to install FD and ID and expose bpf_link to
3423 * user-space, if bpf_link is successfully attached. If not, bpf_link and
3424 * pre-allocated resources are to be freed with bpf_cleanup() call. All the
3425 * transient state is passed around in struct bpf_link_primer.
3426 * This is preferred way to create and initialize bpf_link, especially when
3427 * there are complicated and expensive operations in between creating bpf_link
3428 * itself and attaching it to BPF hook. By using bpf_link_prime() and
3429 * bpf_link_settle() kernel code using bpf_link doesn't have to perform
3430 * expensive (and potentially failing) roll back operations in a rare case
3431 * that file, FD, or ID can't be allocated.
3432 */
bpf_link_prime(struct bpf_link * link,struct bpf_link_primer * primer)3433 int bpf_link_prime(struct bpf_link *link, struct bpf_link_primer *primer)
3434 {
3435 struct file *file;
3436 int fd, id;
3437
3438 fd = get_unused_fd_flags(O_CLOEXEC);
3439 if (fd < 0)
3440 return fd;
3441
3442
3443 id = bpf_link_alloc_id(link);
3444 if (id < 0) {
3445 put_unused_fd(fd);
3446 return id;
3447 }
3448
3449 file = anon_inode_getfile("bpf_link",
3450 link->ops->poll ? &bpf_link_fops_poll : &bpf_link_fops,
3451 link, O_CLOEXEC);
3452 if (IS_ERR(file)) {
3453 bpf_link_free_id(id);
3454 put_unused_fd(fd);
3455 return PTR_ERR(file);
3456 }
3457
3458 primer->link = link;
3459 primer->file = file;
3460 primer->fd = fd;
3461 primer->id = id;
3462 return 0;
3463 }
3464
bpf_link_settle(struct bpf_link_primer * primer)3465 int bpf_link_settle(struct bpf_link_primer *primer)
3466 {
3467 /* make bpf_link fetchable by ID */
3468 spin_lock_bh(&link_idr_lock);
3469 primer->link->id = primer->id;
3470 spin_unlock_bh(&link_idr_lock);
3471 /* make bpf_link fetchable by FD */
3472 fd_install(primer->fd, primer->file);
3473 /* pass through installed FD */
3474 return primer->fd;
3475 }
3476
bpf_link_new_fd(struct bpf_link * link)3477 int bpf_link_new_fd(struct bpf_link *link)
3478 {
3479 return anon_inode_getfd("bpf-link",
3480 link->ops->poll ? &bpf_link_fops_poll : &bpf_link_fops,
3481 link, O_CLOEXEC);
3482 }
3483
bpf_link_get_from_fd(u32 ufd)3484 struct bpf_link *bpf_link_get_from_fd(u32 ufd)
3485 {
3486 CLASS(fd, f)(ufd);
3487 struct bpf_link *link;
3488
3489 if (fd_empty(f))
3490 return ERR_PTR(-EBADF);
3491 if (fd_file(f)->f_op != &bpf_link_fops && fd_file(f)->f_op != &bpf_link_fops_poll)
3492 return ERR_PTR(-EINVAL);
3493
3494 link = fd_file(f)->private_data;
3495 bpf_link_inc(link);
3496 return link;
3497 }
3498 EXPORT_SYMBOL_NS(bpf_link_get_from_fd, "BPF_INTERNAL");
3499
bpf_tracing_link_release(struct bpf_link * link)3500 static void bpf_tracing_link_release(struct bpf_link *link)
3501 {
3502 struct bpf_tracing_link *tr_link =
3503 container_of(link, struct bpf_tracing_link, link.link);
3504
3505 WARN_ON_ONCE(bpf_trampoline_unlink_prog(&tr_link->link,
3506 tr_link->trampoline,
3507 tr_link->tgt_prog));
3508
3509 bpf_trampoline_put(tr_link->trampoline);
3510
3511 /* tgt_prog is NULL if target is a kernel function */
3512 if (tr_link->tgt_prog)
3513 bpf_prog_put(tr_link->tgt_prog);
3514 }
3515
bpf_tracing_link_dealloc(struct bpf_link * link)3516 static void bpf_tracing_link_dealloc(struct bpf_link *link)
3517 {
3518 struct bpf_tracing_link *tr_link =
3519 container_of(link, struct bpf_tracing_link, link.link);
3520
3521 kfree(tr_link);
3522 }
3523
bpf_tracing_link_show_fdinfo(const struct bpf_link * link,struct seq_file * seq)3524 static void bpf_tracing_link_show_fdinfo(const struct bpf_link *link,
3525 struct seq_file *seq)
3526 {
3527 struct bpf_tracing_link *tr_link =
3528 container_of(link, struct bpf_tracing_link, link.link);
3529 u32 target_btf_id, target_obj_id;
3530
3531 bpf_trampoline_unpack_key(tr_link->trampoline->key,
3532 &target_obj_id, &target_btf_id);
3533 seq_printf(seq,
3534 "attach_type:\t%d\n"
3535 "target_obj_id:\t%u\n"
3536 "target_btf_id:\t%u\n"
3537 "cookie:\t%llu\n",
3538 link->attach_type,
3539 target_obj_id,
3540 target_btf_id,
3541 tr_link->link.cookie);
3542 }
3543
bpf_tracing_link_fill_link_info(const struct bpf_link * link,struct bpf_link_info * info)3544 static int bpf_tracing_link_fill_link_info(const struct bpf_link *link,
3545 struct bpf_link_info *info)
3546 {
3547 struct bpf_tracing_link *tr_link =
3548 container_of(link, struct bpf_tracing_link, link.link);
3549
3550 info->tracing.attach_type = link->attach_type;
3551 info->tracing.cookie = tr_link->link.cookie;
3552 bpf_trampoline_unpack_key(tr_link->trampoline->key,
3553 &info->tracing.target_obj_id,
3554 &info->tracing.target_btf_id);
3555
3556 return 0;
3557 }
3558
3559 static const struct bpf_link_ops bpf_tracing_link_lops = {
3560 .release = bpf_tracing_link_release,
3561 .dealloc = bpf_tracing_link_dealloc,
3562 .show_fdinfo = bpf_tracing_link_show_fdinfo,
3563 .fill_link_info = bpf_tracing_link_fill_link_info,
3564 };
3565
bpf_tracing_prog_attach(struct bpf_prog * prog,int tgt_prog_fd,u32 btf_id,u64 bpf_cookie,enum bpf_attach_type attach_type)3566 static int bpf_tracing_prog_attach(struct bpf_prog *prog,
3567 int tgt_prog_fd,
3568 u32 btf_id,
3569 u64 bpf_cookie,
3570 enum bpf_attach_type attach_type)
3571 {
3572 struct bpf_link_primer link_primer;
3573 struct bpf_prog *tgt_prog = NULL;
3574 struct bpf_trampoline *tr = NULL;
3575 struct bpf_tracing_link *link;
3576 u64 key = 0;
3577 int err;
3578
3579 switch (prog->type) {
3580 case BPF_PROG_TYPE_TRACING:
3581 if (prog->expected_attach_type != BPF_TRACE_FENTRY &&
3582 prog->expected_attach_type != BPF_TRACE_FEXIT &&
3583 prog->expected_attach_type != BPF_TRACE_FSESSION &&
3584 prog->expected_attach_type != BPF_MODIFY_RETURN) {
3585 err = -EINVAL;
3586 goto out_put_prog;
3587 }
3588 break;
3589 case BPF_PROG_TYPE_EXT:
3590 if (prog->expected_attach_type != 0) {
3591 err = -EINVAL;
3592 goto out_put_prog;
3593 }
3594 break;
3595 case BPF_PROG_TYPE_LSM:
3596 if (prog->expected_attach_type != BPF_LSM_MAC) {
3597 err = -EINVAL;
3598 goto out_put_prog;
3599 }
3600 break;
3601 default:
3602 err = -EINVAL;
3603 goto out_put_prog;
3604 }
3605
3606 if (!!tgt_prog_fd != !!btf_id) {
3607 err = -EINVAL;
3608 goto out_put_prog;
3609 }
3610
3611 if (tgt_prog_fd) {
3612 /*
3613 * For now we only allow new targets for BPF_PROG_TYPE_EXT. If this
3614 * part would be changed to implement the same for
3615 * BPF_PROG_TYPE_TRACING, do not forget to update the way how
3616 * attach_tracing_prog flag is set.
3617 */
3618 if (prog->type != BPF_PROG_TYPE_EXT) {
3619 err = -EINVAL;
3620 goto out_put_prog;
3621 }
3622
3623 tgt_prog = bpf_prog_get(tgt_prog_fd);
3624 if (IS_ERR(tgt_prog)) {
3625 err = PTR_ERR(tgt_prog);
3626 tgt_prog = NULL;
3627 goto out_put_prog;
3628 }
3629
3630 key = bpf_trampoline_compute_key(tgt_prog, NULL, btf_id);
3631 }
3632
3633 if (prog->expected_attach_type == BPF_TRACE_FSESSION) {
3634 struct bpf_fsession_link *fslink;
3635
3636 fslink = kzalloc_obj(*fslink, GFP_USER);
3637 if (fslink) {
3638 bpf_link_init(&fslink->fexit.link, BPF_LINK_TYPE_TRACING,
3639 &bpf_tracing_link_lops, prog, attach_type);
3640 fslink->fexit.cookie = bpf_cookie;
3641 link = &fslink->link;
3642 } else {
3643 link = NULL;
3644 }
3645 } else {
3646 link = kzalloc_obj(*link, GFP_USER);
3647 }
3648 if (!link) {
3649 err = -ENOMEM;
3650 goto out_put_prog;
3651 }
3652 bpf_link_init(&link->link.link, BPF_LINK_TYPE_TRACING,
3653 &bpf_tracing_link_lops, prog, attach_type);
3654
3655 link->link.cookie = bpf_cookie;
3656
3657 mutex_lock(&prog->aux->dst_mutex);
3658
3659 /* There are a few possible cases here:
3660 *
3661 * - if prog->aux->dst_trampoline is set, the program was just loaded
3662 * and not yet attached to anything, so we can use the values stored
3663 * in prog->aux
3664 *
3665 * - if prog->aux->dst_trampoline is NULL, the program has already been
3666 * attached to a target and its initial target was cleared (below)
3667 *
3668 * - if tgt_prog != NULL, the caller specified tgt_prog_fd +
3669 * target_btf_id using the link_create API.
3670 *
3671 * - if tgt_prog == NULL when this function was called using the old
3672 * raw_tracepoint_open API, and we need a target from prog->aux
3673 *
3674 * - if prog->aux->dst_trampoline and tgt_prog is NULL, the program
3675 * was detached and is going for re-attachment.
3676 *
3677 * - if prog->aux->dst_trampoline is NULL and tgt_prog and prog->aux->attach_btf
3678 * are NULL, then program was already attached and user did not provide
3679 * tgt_prog_fd so we have no way to find out or create trampoline
3680 */
3681 if (!prog->aux->dst_trampoline && !tgt_prog) {
3682 /*
3683 * Allow re-attach for TRACING and LSM programs. If it's
3684 * currently linked, bpf_trampoline_link_prog will fail.
3685 * EXT programs need to specify tgt_prog_fd, so they
3686 * re-attach in separate code path.
3687 */
3688 if (prog->type != BPF_PROG_TYPE_TRACING &&
3689 prog->type != BPF_PROG_TYPE_LSM) {
3690 err = -EINVAL;
3691 goto out_unlock;
3692 }
3693 /* We can allow re-attach only if we have valid attach_btf. */
3694 if (!prog->aux->attach_btf) {
3695 err = -EINVAL;
3696 goto out_unlock;
3697 }
3698 btf_id = prog->aux->attach_btf_id;
3699 key = bpf_trampoline_compute_key(NULL, prog->aux->attach_btf, btf_id);
3700 }
3701
3702 if (!prog->aux->dst_trampoline ||
3703 (key && key != prog->aux->dst_trampoline->key)) {
3704 /* If there is no saved target, or the specified target is
3705 * different from the destination specified at load time, we
3706 * need a new trampoline and a check for compatibility
3707 */
3708 struct bpf_attach_target_info tgt_info = {};
3709
3710 err = bpf_check_attach_target(NULL, prog, tgt_prog, btf_id,
3711 &tgt_info);
3712 if (err)
3713 goto out_unlock;
3714
3715 if (tgt_info.tgt_mod) {
3716 module_put(prog->aux->mod);
3717 prog->aux->mod = tgt_info.tgt_mod;
3718 }
3719
3720 tr = bpf_trampoline_get(key, &tgt_info);
3721 if (!tr) {
3722 err = -ENOMEM;
3723 goto out_unlock;
3724 }
3725 } else {
3726 /* The caller didn't specify a target, or the target was the
3727 * same as the destination supplied during program load. This
3728 * means we can reuse the trampoline and reference from program
3729 * load time, and there is no need to allocate a new one. This
3730 * can only happen once for any program, as the saved values in
3731 * prog->aux are cleared below.
3732 */
3733 tr = prog->aux->dst_trampoline;
3734 tgt_prog = prog->aux->dst_prog;
3735 }
3736
3737 err = bpf_link_prime(&link->link.link, &link_primer);
3738 if (err)
3739 goto out_unlock;
3740
3741 err = bpf_trampoline_link_prog(&link->link, tr, tgt_prog);
3742 if (err) {
3743 bpf_link_cleanup(&link_primer);
3744 link = NULL;
3745 goto out_unlock;
3746 }
3747
3748 link->tgt_prog = tgt_prog;
3749 link->trampoline = tr;
3750
3751 /* Always clear the trampoline and target prog from prog->aux to make
3752 * sure the original attach destination is not kept alive after a
3753 * program is (re-)attached to another target.
3754 */
3755 if (prog->aux->dst_prog &&
3756 (tgt_prog_fd || tr != prog->aux->dst_trampoline))
3757 /* got extra prog ref from syscall, or attaching to different prog */
3758 bpf_prog_put(prog->aux->dst_prog);
3759 if (prog->aux->dst_trampoline && tr != prog->aux->dst_trampoline)
3760 /* we allocated a new trampoline, so free the old one */
3761 bpf_trampoline_put(prog->aux->dst_trampoline);
3762
3763 prog->aux->dst_prog = NULL;
3764 prog->aux->dst_trampoline = NULL;
3765 mutex_unlock(&prog->aux->dst_mutex);
3766
3767 return bpf_link_settle(&link_primer);
3768 out_unlock:
3769 if (tr && tr != prog->aux->dst_trampoline)
3770 bpf_trampoline_put(tr);
3771 mutex_unlock(&prog->aux->dst_mutex);
3772 kfree(link);
3773 out_put_prog:
3774 if (tgt_prog_fd && tgt_prog)
3775 bpf_prog_put(tgt_prog);
3776 return err;
3777 }
3778
bpf_raw_tp_link_release(struct bpf_link * link)3779 static void bpf_raw_tp_link_release(struct bpf_link *link)
3780 {
3781 struct bpf_raw_tp_link *raw_tp =
3782 container_of(link, struct bpf_raw_tp_link, link);
3783
3784 bpf_probe_unregister(raw_tp->btp, raw_tp);
3785 bpf_put_raw_tracepoint(raw_tp->btp);
3786 }
3787
bpf_raw_tp_link_dealloc(struct bpf_link * link)3788 static void bpf_raw_tp_link_dealloc(struct bpf_link *link)
3789 {
3790 struct bpf_raw_tp_link *raw_tp =
3791 container_of(link, struct bpf_raw_tp_link, link);
3792
3793 kfree(raw_tp);
3794 }
3795
bpf_raw_tp_link_show_fdinfo(const struct bpf_link * link,struct seq_file * seq)3796 static void bpf_raw_tp_link_show_fdinfo(const struct bpf_link *link,
3797 struct seq_file *seq)
3798 {
3799 struct bpf_raw_tp_link *raw_tp_link =
3800 container_of(link, struct bpf_raw_tp_link, link);
3801
3802 seq_printf(seq,
3803 "tp_name:\t%s\n"
3804 "cookie:\t%llu\n",
3805 raw_tp_link->btp->tp->name,
3806 raw_tp_link->cookie);
3807 }
3808
bpf_copy_to_user(char __user * ubuf,const char * buf,u32 ulen,u32 len)3809 static int bpf_copy_to_user(char __user *ubuf, const char *buf, u32 ulen,
3810 u32 len)
3811 {
3812 if (ulen >= len + 1) {
3813 if (copy_to_user(ubuf, buf, len + 1))
3814 return -EFAULT;
3815 } else {
3816 char zero = '\0';
3817
3818 if (copy_to_user(ubuf, buf, ulen - 1))
3819 return -EFAULT;
3820 if (put_user(zero, ubuf + ulen - 1))
3821 return -EFAULT;
3822 return -ENOSPC;
3823 }
3824
3825 return 0;
3826 }
3827
bpf_raw_tp_link_fill_link_info(const struct bpf_link * link,struct bpf_link_info * info)3828 static int bpf_raw_tp_link_fill_link_info(const struct bpf_link *link,
3829 struct bpf_link_info *info)
3830 {
3831 struct bpf_raw_tp_link *raw_tp_link =
3832 container_of(link, struct bpf_raw_tp_link, link);
3833 char __user *ubuf = u64_to_user_ptr(info->raw_tracepoint.tp_name);
3834 const char *tp_name = raw_tp_link->btp->tp->name;
3835 u32 ulen = info->raw_tracepoint.tp_name_len;
3836 size_t tp_len = strlen(tp_name);
3837
3838 if (!ulen ^ !ubuf)
3839 return -EINVAL;
3840
3841 info->raw_tracepoint.tp_name_len = tp_len + 1;
3842 info->raw_tracepoint.cookie = raw_tp_link->cookie;
3843
3844 if (!ubuf)
3845 return 0;
3846
3847 return bpf_copy_to_user(ubuf, tp_name, ulen, tp_len);
3848 }
3849
3850 static const struct bpf_link_ops bpf_raw_tp_link_lops = {
3851 .release = bpf_raw_tp_link_release,
3852 .dealloc_deferred = bpf_raw_tp_link_dealloc,
3853 .show_fdinfo = bpf_raw_tp_link_show_fdinfo,
3854 .fill_link_info = bpf_raw_tp_link_fill_link_info,
3855 };
3856
3857 #ifdef CONFIG_PERF_EVENTS
3858 struct bpf_perf_link {
3859 struct bpf_link link;
3860 struct file *perf_file;
3861 };
3862
bpf_perf_link_release(struct bpf_link * link)3863 static void bpf_perf_link_release(struct bpf_link *link)
3864 {
3865 struct bpf_perf_link *perf_link = container_of(link, struct bpf_perf_link, link);
3866 struct perf_event *event = perf_link->perf_file->private_data;
3867
3868 perf_event_free_bpf_prog(event);
3869 fput(perf_link->perf_file);
3870 }
3871
bpf_perf_link_dealloc(struct bpf_link * link)3872 static void bpf_perf_link_dealloc(struct bpf_link *link)
3873 {
3874 struct bpf_perf_link *perf_link = container_of(link, struct bpf_perf_link, link);
3875
3876 kfree(perf_link);
3877 }
3878
bpf_perf_link_fill_common(const struct perf_event * event,char __user * uname,u32 * ulenp,u64 * probe_offset,u64 * probe_addr,u32 * fd_type,unsigned long * missed)3879 static int bpf_perf_link_fill_common(const struct perf_event *event,
3880 char __user *uname, u32 *ulenp,
3881 u64 *probe_offset, u64 *probe_addr,
3882 u32 *fd_type, unsigned long *missed)
3883 {
3884 const char *buf;
3885 u32 prog_id, ulen;
3886 size_t len;
3887 int err;
3888
3889 ulen = *ulenp;
3890 if (!ulen ^ !uname)
3891 return -EINVAL;
3892
3893 err = bpf_get_perf_event_info(event, &prog_id, fd_type, &buf,
3894 probe_offset, probe_addr, missed);
3895 if (err)
3896 return err;
3897
3898 if (buf) {
3899 len = strlen(buf);
3900 *ulenp = len + 1;
3901 } else {
3902 *ulenp = 1;
3903 }
3904 if (!uname)
3905 return 0;
3906
3907 if (buf) {
3908 err = bpf_copy_to_user(uname, buf, ulen, len);
3909 if (err)
3910 return err;
3911 } else {
3912 char zero = '\0';
3913
3914 if (put_user(zero, uname))
3915 return -EFAULT;
3916 }
3917 return 0;
3918 }
3919
3920 #ifdef CONFIG_KPROBE_EVENTS
bpf_perf_link_fill_kprobe(const struct perf_event * event,struct bpf_link_info * info)3921 static int bpf_perf_link_fill_kprobe(const struct perf_event *event,
3922 struct bpf_link_info *info)
3923 {
3924 unsigned long missed;
3925 char __user *uname;
3926 u64 addr, offset;
3927 u32 ulen, type;
3928 int err;
3929
3930 uname = u64_to_user_ptr(info->perf_event.kprobe.func_name);
3931 ulen = info->perf_event.kprobe.name_len;
3932 err = bpf_perf_link_fill_common(event, uname, &ulen, &offset, &addr,
3933 &type, &missed);
3934 if (err)
3935 return err;
3936 if (type == BPF_FD_TYPE_KRETPROBE)
3937 info->perf_event.type = BPF_PERF_EVENT_KRETPROBE;
3938 else
3939 info->perf_event.type = BPF_PERF_EVENT_KPROBE;
3940 info->perf_event.kprobe.name_len = ulen;
3941 info->perf_event.kprobe.offset = offset;
3942 info->perf_event.kprobe.missed = missed;
3943 if (!kallsyms_show_value(current_cred()))
3944 addr = 0;
3945 info->perf_event.kprobe.addr = addr;
3946 info->perf_event.kprobe.cookie = event->bpf_cookie;
3947 return 0;
3948 }
3949
bpf_perf_link_fdinfo_kprobe(const struct perf_event * event,struct seq_file * seq)3950 static void bpf_perf_link_fdinfo_kprobe(const struct perf_event *event,
3951 struct seq_file *seq)
3952 {
3953 const char *name;
3954 int err;
3955 u32 prog_id, type;
3956 u64 offset, addr;
3957 unsigned long missed;
3958
3959 err = bpf_get_perf_event_info(event, &prog_id, &type, &name,
3960 &offset, &addr, &missed);
3961 if (err)
3962 return;
3963
3964 seq_printf(seq,
3965 "name:\t%s\n"
3966 "offset:\t%#llx\n"
3967 "missed:\t%lu\n"
3968 "addr:\t%#llx\n"
3969 "event_type:\t%s\n"
3970 "cookie:\t%llu\n",
3971 name, offset, missed, addr,
3972 type == BPF_FD_TYPE_KRETPROBE ? "kretprobe" : "kprobe",
3973 event->bpf_cookie);
3974 }
3975 #endif
3976
3977 #ifdef CONFIG_UPROBE_EVENTS
bpf_perf_link_fill_uprobe(const struct perf_event * event,struct bpf_link_info * info)3978 static int bpf_perf_link_fill_uprobe(const struct perf_event *event,
3979 struct bpf_link_info *info)
3980 {
3981 u64 ref_ctr_offset, offset;
3982 char __user *uname;
3983 u32 ulen, type;
3984 int err;
3985
3986 uname = u64_to_user_ptr(info->perf_event.uprobe.file_name);
3987 ulen = info->perf_event.uprobe.name_len;
3988 err = bpf_perf_link_fill_common(event, uname, &ulen, &offset, &ref_ctr_offset,
3989 &type, NULL);
3990 if (err)
3991 return err;
3992
3993 if (type == BPF_FD_TYPE_URETPROBE)
3994 info->perf_event.type = BPF_PERF_EVENT_URETPROBE;
3995 else
3996 info->perf_event.type = BPF_PERF_EVENT_UPROBE;
3997 info->perf_event.uprobe.name_len = ulen;
3998 info->perf_event.uprobe.offset = offset;
3999 info->perf_event.uprobe.cookie = event->bpf_cookie;
4000 info->perf_event.uprobe.ref_ctr_offset = ref_ctr_offset;
4001 return 0;
4002 }
4003
bpf_perf_link_fdinfo_uprobe(const struct perf_event * event,struct seq_file * seq)4004 static void bpf_perf_link_fdinfo_uprobe(const struct perf_event *event,
4005 struct seq_file *seq)
4006 {
4007 const char *name;
4008 int err;
4009 u32 prog_id, type;
4010 u64 offset, ref_ctr_offset;
4011 unsigned long missed;
4012
4013 err = bpf_get_perf_event_info(event, &prog_id, &type, &name,
4014 &offset, &ref_ctr_offset, &missed);
4015 if (err)
4016 return;
4017
4018 seq_printf(seq,
4019 "name:\t%s\n"
4020 "offset:\t%#llx\n"
4021 "ref_ctr_offset:\t%#llx\n"
4022 "event_type:\t%s\n"
4023 "cookie:\t%llu\n",
4024 name, offset, ref_ctr_offset,
4025 type == BPF_FD_TYPE_URETPROBE ? "uretprobe" : "uprobe",
4026 event->bpf_cookie);
4027 }
4028 #endif
4029
bpf_perf_link_fill_probe(const struct perf_event * event,struct bpf_link_info * info)4030 static int bpf_perf_link_fill_probe(const struct perf_event *event,
4031 struct bpf_link_info *info)
4032 {
4033 #ifdef CONFIG_KPROBE_EVENTS
4034 if (event->tp_event->flags & TRACE_EVENT_FL_KPROBE)
4035 return bpf_perf_link_fill_kprobe(event, info);
4036 #endif
4037 #ifdef CONFIG_UPROBE_EVENTS
4038 if (event->tp_event->flags & TRACE_EVENT_FL_UPROBE)
4039 return bpf_perf_link_fill_uprobe(event, info);
4040 #endif
4041 return -EOPNOTSUPP;
4042 }
4043
bpf_perf_link_fill_tracepoint(const struct perf_event * event,struct bpf_link_info * info)4044 static int bpf_perf_link_fill_tracepoint(const struct perf_event *event,
4045 struct bpf_link_info *info)
4046 {
4047 char __user *uname;
4048 u32 ulen;
4049 int err;
4050
4051 uname = u64_to_user_ptr(info->perf_event.tracepoint.tp_name);
4052 ulen = info->perf_event.tracepoint.name_len;
4053 err = bpf_perf_link_fill_common(event, uname, &ulen, NULL, NULL, NULL, NULL);
4054 if (err)
4055 return err;
4056
4057 info->perf_event.type = BPF_PERF_EVENT_TRACEPOINT;
4058 info->perf_event.tracepoint.name_len = ulen;
4059 info->perf_event.tracepoint.cookie = event->bpf_cookie;
4060 return 0;
4061 }
4062
bpf_perf_link_fill_perf_event(const struct perf_event * event,struct bpf_link_info * info)4063 static int bpf_perf_link_fill_perf_event(const struct perf_event *event,
4064 struct bpf_link_info *info)
4065 {
4066 info->perf_event.event.type = event->attr.type;
4067 info->perf_event.event.config = event->attr.config;
4068 info->perf_event.event.cookie = event->bpf_cookie;
4069 info->perf_event.type = BPF_PERF_EVENT_EVENT;
4070 return 0;
4071 }
4072
bpf_perf_link_fill_link_info(const struct bpf_link * link,struct bpf_link_info * info)4073 static int bpf_perf_link_fill_link_info(const struct bpf_link *link,
4074 struct bpf_link_info *info)
4075 {
4076 struct bpf_perf_link *perf_link;
4077 const struct perf_event *event;
4078
4079 perf_link = container_of(link, struct bpf_perf_link, link);
4080 event = perf_get_event(perf_link->perf_file);
4081 if (IS_ERR(event))
4082 return PTR_ERR(event);
4083
4084 switch (event->prog->type) {
4085 case BPF_PROG_TYPE_PERF_EVENT:
4086 return bpf_perf_link_fill_perf_event(event, info);
4087 case BPF_PROG_TYPE_TRACEPOINT:
4088 return bpf_perf_link_fill_tracepoint(event, info);
4089 case BPF_PROG_TYPE_KPROBE:
4090 return bpf_perf_link_fill_probe(event, info);
4091 default:
4092 return -EOPNOTSUPP;
4093 }
4094 }
4095
bpf_perf_event_link_show_fdinfo(const struct perf_event * event,struct seq_file * seq)4096 static void bpf_perf_event_link_show_fdinfo(const struct perf_event *event,
4097 struct seq_file *seq)
4098 {
4099 seq_printf(seq,
4100 "type:\t%u\n"
4101 "config:\t%llu\n"
4102 "event_type:\t%s\n"
4103 "cookie:\t%llu\n",
4104 event->attr.type, event->attr.config,
4105 "event", event->bpf_cookie);
4106 }
4107
bpf_tracepoint_link_show_fdinfo(const struct perf_event * event,struct seq_file * seq)4108 static void bpf_tracepoint_link_show_fdinfo(const struct perf_event *event,
4109 struct seq_file *seq)
4110 {
4111 int err;
4112 const char *name;
4113 u32 prog_id;
4114
4115 err = bpf_get_perf_event_info(event, &prog_id, NULL, &name, NULL,
4116 NULL, NULL);
4117 if (err)
4118 return;
4119
4120 seq_printf(seq,
4121 "tp_name:\t%s\n"
4122 "event_type:\t%s\n"
4123 "cookie:\t%llu\n",
4124 name, "tracepoint", event->bpf_cookie);
4125 }
4126
bpf_probe_link_show_fdinfo(const struct perf_event * event,struct seq_file * seq)4127 static void bpf_probe_link_show_fdinfo(const struct perf_event *event,
4128 struct seq_file *seq)
4129 {
4130 #ifdef CONFIG_KPROBE_EVENTS
4131 if (event->tp_event->flags & TRACE_EVENT_FL_KPROBE)
4132 return bpf_perf_link_fdinfo_kprobe(event, seq);
4133 #endif
4134
4135 #ifdef CONFIG_UPROBE_EVENTS
4136 if (event->tp_event->flags & TRACE_EVENT_FL_UPROBE)
4137 return bpf_perf_link_fdinfo_uprobe(event, seq);
4138 #endif
4139 }
4140
bpf_perf_link_show_fdinfo(const struct bpf_link * link,struct seq_file * seq)4141 static void bpf_perf_link_show_fdinfo(const struct bpf_link *link,
4142 struct seq_file *seq)
4143 {
4144 struct bpf_perf_link *perf_link;
4145 const struct perf_event *event;
4146
4147 perf_link = container_of(link, struct bpf_perf_link, link);
4148 event = perf_get_event(perf_link->perf_file);
4149 if (IS_ERR(event))
4150 return;
4151
4152 switch (event->prog->type) {
4153 case BPF_PROG_TYPE_PERF_EVENT:
4154 return bpf_perf_event_link_show_fdinfo(event, seq);
4155 case BPF_PROG_TYPE_TRACEPOINT:
4156 return bpf_tracepoint_link_show_fdinfo(event, seq);
4157 case BPF_PROG_TYPE_KPROBE:
4158 return bpf_probe_link_show_fdinfo(event, seq);
4159 default:
4160 return;
4161 }
4162 }
4163
4164 static const struct bpf_link_ops bpf_perf_link_lops = {
4165 .release = bpf_perf_link_release,
4166 .dealloc = bpf_perf_link_dealloc,
4167 .fill_link_info = bpf_perf_link_fill_link_info,
4168 .show_fdinfo = bpf_perf_link_show_fdinfo,
4169 };
4170
bpf_perf_link_attach(const union bpf_attr * attr,struct bpf_prog * prog)4171 static int bpf_perf_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
4172 {
4173 struct bpf_link_primer link_primer;
4174 struct bpf_perf_link *link;
4175 struct perf_event *event;
4176 struct file *perf_file;
4177 int err;
4178
4179 if (attr->link_create.flags)
4180 return -EINVAL;
4181
4182 perf_file = perf_event_get(attr->link_create.target_fd);
4183 if (IS_ERR(perf_file))
4184 return PTR_ERR(perf_file);
4185
4186 link = kzalloc_obj(*link, GFP_USER);
4187 if (!link) {
4188 err = -ENOMEM;
4189 goto out_put_file;
4190 }
4191 bpf_link_init(&link->link, BPF_LINK_TYPE_PERF_EVENT, &bpf_perf_link_lops, prog,
4192 attr->link_create.attach_type);
4193 link->perf_file = perf_file;
4194
4195 err = bpf_link_prime(&link->link, &link_primer);
4196 if (err) {
4197 kfree(link);
4198 goto out_put_file;
4199 }
4200
4201 event = perf_file->private_data;
4202 err = perf_event_set_bpf_prog(event, prog, attr->link_create.perf_event.bpf_cookie);
4203 if (err) {
4204 bpf_link_cleanup(&link_primer);
4205 goto out_put_file;
4206 }
4207 /* perf_event_set_bpf_prog() doesn't take its own refcnt on prog */
4208 bpf_prog_inc(prog);
4209
4210 return bpf_link_settle(&link_primer);
4211
4212 out_put_file:
4213 fput(perf_file);
4214 return err;
4215 }
4216 #else
bpf_perf_link_attach(const union bpf_attr * attr,struct bpf_prog * prog)4217 static int bpf_perf_link_attach(const union bpf_attr *attr, struct bpf_prog *prog)
4218 {
4219 return -EOPNOTSUPP;
4220 }
4221 #endif /* CONFIG_PERF_EVENTS */
4222
bpf_raw_tp_link_attach(struct bpf_prog * prog,const char __user * user_tp_name,u64 cookie,enum bpf_attach_type attach_type)4223 static int bpf_raw_tp_link_attach(struct bpf_prog *prog,
4224 const char __user *user_tp_name, u64 cookie,
4225 enum bpf_attach_type attach_type)
4226 {
4227 struct bpf_link_primer link_primer;
4228 struct bpf_raw_tp_link *link;
4229 struct bpf_raw_event_map *btp;
4230 const char *tp_name;
4231 char buf[128];
4232 int err;
4233
4234 switch (prog->type) {
4235 case BPF_PROG_TYPE_TRACING:
4236 case BPF_PROG_TYPE_EXT:
4237 case BPF_PROG_TYPE_LSM:
4238 if (user_tp_name)
4239 /* The attach point for this category of programs
4240 * should be specified via btf_id during program load.
4241 */
4242 return -EINVAL;
4243 if (prog->type == BPF_PROG_TYPE_TRACING &&
4244 prog->expected_attach_type == BPF_TRACE_RAW_TP) {
4245 tp_name = prog->aux->attach_func_name;
4246 break;
4247 }
4248 return bpf_tracing_prog_attach(prog, 0, 0, 0, attach_type);
4249 case BPF_PROG_TYPE_RAW_TRACEPOINT:
4250 case BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE:
4251 if (strncpy_from_user(buf, user_tp_name, sizeof(buf) - 1) < 0)
4252 return -EFAULT;
4253 buf[sizeof(buf) - 1] = 0;
4254 tp_name = buf;
4255 break;
4256 default:
4257 return -EINVAL;
4258 }
4259
4260 btp = bpf_get_raw_tracepoint(tp_name);
4261 if (!btp)
4262 return -ENOENT;
4263
4264 link = kzalloc_obj(*link, GFP_USER);
4265 if (!link) {
4266 err = -ENOMEM;
4267 goto out_put_btp;
4268 }
4269 bpf_link_init_sleepable(&link->link, BPF_LINK_TYPE_RAW_TRACEPOINT,
4270 &bpf_raw_tp_link_lops, prog, attach_type,
4271 tracepoint_is_faultable(btp->tp));
4272 link->btp = btp;
4273 link->cookie = cookie;
4274
4275 err = bpf_link_prime(&link->link, &link_primer);
4276 if (err) {
4277 kfree(link);
4278 goto out_put_btp;
4279 }
4280
4281 err = bpf_probe_register(link->btp, link);
4282 if (err) {
4283 bpf_link_cleanup(&link_primer);
4284 goto out_put_btp;
4285 }
4286
4287 return bpf_link_settle(&link_primer);
4288
4289 out_put_btp:
4290 bpf_put_raw_tracepoint(btp);
4291 return err;
4292 }
4293
4294 #define BPF_RAW_TRACEPOINT_OPEN_LAST_FIELD raw_tracepoint.cookie
4295
bpf_raw_tracepoint_open(const union bpf_attr * attr)4296 static int bpf_raw_tracepoint_open(const union bpf_attr *attr)
4297 {
4298 struct bpf_prog *prog;
4299 void __user *tp_name;
4300 __u64 cookie;
4301 int fd;
4302
4303 if (CHECK_ATTR(BPF_RAW_TRACEPOINT_OPEN))
4304 return -EINVAL;
4305
4306 prog = bpf_prog_get(attr->raw_tracepoint.prog_fd);
4307 if (IS_ERR(prog))
4308 return PTR_ERR(prog);
4309
4310 tp_name = u64_to_user_ptr(attr->raw_tracepoint.name);
4311 cookie = attr->raw_tracepoint.cookie;
4312 fd = bpf_raw_tp_link_attach(prog, tp_name, cookie, prog->expected_attach_type);
4313 if (fd < 0)
4314 bpf_prog_put(prog);
4315 return fd;
4316 }
4317
4318 static enum bpf_prog_type
attach_type_to_prog_type(enum bpf_attach_type attach_type)4319 attach_type_to_prog_type(enum bpf_attach_type attach_type)
4320 {
4321 switch (attach_type) {
4322 case BPF_CGROUP_INET_INGRESS:
4323 case BPF_CGROUP_INET_EGRESS:
4324 return BPF_PROG_TYPE_CGROUP_SKB;
4325 case BPF_CGROUP_INET_SOCK_CREATE:
4326 case BPF_CGROUP_INET_SOCK_RELEASE:
4327 case BPF_CGROUP_INET4_POST_BIND:
4328 case BPF_CGROUP_INET6_POST_BIND:
4329 return BPF_PROG_TYPE_CGROUP_SOCK;
4330 case BPF_CGROUP_INET4_BIND:
4331 case BPF_CGROUP_INET6_BIND:
4332 case BPF_CGROUP_INET4_CONNECT:
4333 case BPF_CGROUP_INET6_CONNECT:
4334 case BPF_CGROUP_UNIX_CONNECT:
4335 case BPF_CGROUP_INET4_GETPEERNAME:
4336 case BPF_CGROUP_INET6_GETPEERNAME:
4337 case BPF_CGROUP_UNIX_GETPEERNAME:
4338 case BPF_CGROUP_INET4_GETSOCKNAME:
4339 case BPF_CGROUP_INET6_GETSOCKNAME:
4340 case BPF_CGROUP_UNIX_GETSOCKNAME:
4341 case BPF_CGROUP_UDP4_SENDMSG:
4342 case BPF_CGROUP_UDP6_SENDMSG:
4343 case BPF_CGROUP_UNIX_SENDMSG:
4344 case BPF_CGROUP_UDP4_RECVMSG:
4345 case BPF_CGROUP_UDP6_RECVMSG:
4346 case BPF_CGROUP_UNIX_RECVMSG:
4347 return BPF_PROG_TYPE_CGROUP_SOCK_ADDR;
4348 case BPF_CGROUP_SOCK_OPS:
4349 return BPF_PROG_TYPE_SOCK_OPS;
4350 case BPF_CGROUP_DEVICE:
4351 return BPF_PROG_TYPE_CGROUP_DEVICE;
4352 case BPF_SK_MSG_VERDICT:
4353 return BPF_PROG_TYPE_SK_MSG;
4354 case BPF_SK_SKB_STREAM_PARSER:
4355 case BPF_SK_SKB_STREAM_VERDICT:
4356 case BPF_SK_SKB_VERDICT:
4357 return BPF_PROG_TYPE_SK_SKB;
4358 case BPF_LIRC_MODE2:
4359 return BPF_PROG_TYPE_LIRC_MODE2;
4360 case BPF_FLOW_DISSECTOR:
4361 return BPF_PROG_TYPE_FLOW_DISSECTOR;
4362 case BPF_CGROUP_SYSCTL:
4363 return BPF_PROG_TYPE_CGROUP_SYSCTL;
4364 case BPF_CGROUP_GETSOCKOPT:
4365 case BPF_CGROUP_SETSOCKOPT:
4366 return BPF_PROG_TYPE_CGROUP_SOCKOPT;
4367 case BPF_TRACE_ITER:
4368 case BPF_TRACE_RAW_TP:
4369 case BPF_TRACE_FENTRY:
4370 case BPF_TRACE_FEXIT:
4371 case BPF_TRACE_FSESSION:
4372 case BPF_MODIFY_RETURN:
4373 return BPF_PROG_TYPE_TRACING;
4374 case BPF_LSM_MAC:
4375 return BPF_PROG_TYPE_LSM;
4376 case BPF_SK_LOOKUP:
4377 return BPF_PROG_TYPE_SK_LOOKUP;
4378 case BPF_XDP:
4379 return BPF_PROG_TYPE_XDP;
4380 case BPF_LSM_CGROUP:
4381 return BPF_PROG_TYPE_LSM;
4382 case BPF_TCX_INGRESS:
4383 case BPF_TCX_EGRESS:
4384 case BPF_NETKIT_PRIMARY:
4385 case BPF_NETKIT_PEER:
4386 return BPF_PROG_TYPE_SCHED_CLS;
4387 default:
4388 return BPF_PROG_TYPE_UNSPEC;
4389 }
4390 }
4391
bpf_prog_attach_check_attach_type(const struct bpf_prog * prog,enum bpf_attach_type attach_type)4392 static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog,
4393 enum bpf_attach_type attach_type)
4394 {
4395 enum bpf_prog_type ptype;
4396
4397 switch (prog->type) {
4398 case BPF_PROG_TYPE_CGROUP_SOCK:
4399 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
4400 case BPF_PROG_TYPE_CGROUP_SOCKOPT:
4401 case BPF_PROG_TYPE_SK_LOOKUP:
4402 return attach_type == prog->expected_attach_type ? 0 : -EINVAL;
4403 case BPF_PROG_TYPE_CGROUP_SKB:
4404 if (!bpf_token_capable(prog->aux->token, CAP_NET_ADMIN))
4405 /* cg-skb progs can be loaded by unpriv user.
4406 * check permissions at attach time.
4407 */
4408 return -EPERM;
4409
4410 ptype = attach_type_to_prog_type(attach_type);
4411 if (prog->type != ptype)
4412 return -EINVAL;
4413
4414 return prog->enforce_expected_attach_type &&
4415 prog->expected_attach_type != attach_type ?
4416 -EINVAL : 0;
4417 case BPF_PROG_TYPE_EXT:
4418 return 0;
4419 case BPF_PROG_TYPE_NETFILTER:
4420 if (attach_type != BPF_NETFILTER)
4421 return -EINVAL;
4422 return 0;
4423 case BPF_PROG_TYPE_PERF_EVENT:
4424 case BPF_PROG_TYPE_TRACEPOINT:
4425 if (attach_type != BPF_PERF_EVENT)
4426 return -EINVAL;
4427 return 0;
4428 case BPF_PROG_TYPE_KPROBE:
4429 if (prog->expected_attach_type == BPF_TRACE_KPROBE_MULTI &&
4430 attach_type != BPF_TRACE_KPROBE_MULTI)
4431 return -EINVAL;
4432 if (prog->expected_attach_type == BPF_TRACE_KPROBE_SESSION &&
4433 attach_type != BPF_TRACE_KPROBE_SESSION)
4434 return -EINVAL;
4435 if (prog->expected_attach_type == BPF_TRACE_UPROBE_MULTI &&
4436 attach_type != BPF_TRACE_UPROBE_MULTI)
4437 return -EINVAL;
4438 if (prog->expected_attach_type == BPF_TRACE_UPROBE_SESSION &&
4439 attach_type != BPF_TRACE_UPROBE_SESSION)
4440 return -EINVAL;
4441 if (attach_type != BPF_PERF_EVENT &&
4442 attach_type != BPF_TRACE_KPROBE_MULTI &&
4443 attach_type != BPF_TRACE_KPROBE_SESSION &&
4444 attach_type != BPF_TRACE_UPROBE_MULTI &&
4445 attach_type != BPF_TRACE_UPROBE_SESSION)
4446 return -EINVAL;
4447 return 0;
4448 case BPF_PROG_TYPE_SCHED_CLS:
4449 if (attach_type != BPF_TCX_INGRESS &&
4450 attach_type != BPF_TCX_EGRESS &&
4451 attach_type != BPF_NETKIT_PRIMARY &&
4452 attach_type != BPF_NETKIT_PEER)
4453 return -EINVAL;
4454 return 0;
4455 default:
4456 ptype = attach_type_to_prog_type(attach_type);
4457 if (ptype == BPF_PROG_TYPE_UNSPEC || ptype != prog->type)
4458 return -EINVAL;
4459 return 0;
4460 }
4461 }
4462
is_cgroup_prog_type(enum bpf_prog_type ptype,enum bpf_attach_type atype,bool check_atype)4463 static bool is_cgroup_prog_type(enum bpf_prog_type ptype, enum bpf_attach_type atype,
4464 bool check_atype)
4465 {
4466 switch (ptype) {
4467 case BPF_PROG_TYPE_CGROUP_DEVICE:
4468 case BPF_PROG_TYPE_CGROUP_SKB:
4469 case BPF_PROG_TYPE_CGROUP_SOCK:
4470 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
4471 case BPF_PROG_TYPE_CGROUP_SOCKOPT:
4472 case BPF_PROG_TYPE_CGROUP_SYSCTL:
4473 case BPF_PROG_TYPE_SOCK_OPS:
4474 return true;
4475 case BPF_PROG_TYPE_LSM:
4476 return check_atype ? atype == BPF_LSM_CGROUP : true;
4477 default:
4478 return false;
4479 }
4480 }
4481
4482 #define BPF_PROG_ATTACH_LAST_FIELD expected_revision
4483
4484 #define BPF_F_ATTACH_MASK_BASE \
4485 (BPF_F_ALLOW_OVERRIDE | \
4486 BPF_F_ALLOW_MULTI | \
4487 BPF_F_REPLACE | \
4488 BPF_F_PREORDER)
4489
4490 #define BPF_F_ATTACH_MASK_MPROG \
4491 (BPF_F_REPLACE | \
4492 BPF_F_BEFORE | \
4493 BPF_F_AFTER | \
4494 BPF_F_ID | \
4495 BPF_F_LINK)
4496
bpf_prog_attach(const union bpf_attr * attr)4497 static int bpf_prog_attach(const union bpf_attr *attr)
4498 {
4499 enum bpf_prog_type ptype;
4500 struct bpf_prog *prog;
4501 int ret;
4502
4503 if (CHECK_ATTR(BPF_PROG_ATTACH))
4504 return -EINVAL;
4505
4506 ptype = attach_type_to_prog_type(attr->attach_type);
4507 if (ptype == BPF_PROG_TYPE_UNSPEC)
4508 return -EINVAL;
4509 if (bpf_mprog_supported(ptype)) {
4510 if (attr->attach_flags & ~BPF_F_ATTACH_MASK_MPROG)
4511 return -EINVAL;
4512 } else if (is_cgroup_prog_type(ptype, 0, false)) {
4513 if (attr->attach_flags & ~(BPF_F_ATTACH_MASK_BASE | BPF_F_ATTACH_MASK_MPROG))
4514 return -EINVAL;
4515 } else {
4516 if (attr->attach_flags & ~BPF_F_ATTACH_MASK_BASE)
4517 return -EINVAL;
4518 if (attr->relative_fd ||
4519 attr->expected_revision)
4520 return -EINVAL;
4521 }
4522
4523 prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype);
4524 if (IS_ERR(prog))
4525 return PTR_ERR(prog);
4526
4527 if (bpf_prog_attach_check_attach_type(prog, attr->attach_type)) {
4528 bpf_prog_put(prog);
4529 return -EINVAL;
4530 }
4531
4532 if (is_cgroup_prog_type(ptype, prog->expected_attach_type, true)) {
4533 ret = cgroup_bpf_prog_attach(attr, ptype, prog);
4534 goto out;
4535 }
4536
4537 switch (ptype) {
4538 case BPF_PROG_TYPE_SK_SKB:
4539 case BPF_PROG_TYPE_SK_MSG:
4540 ret = sock_map_get_from_fd(attr, prog);
4541 break;
4542 case BPF_PROG_TYPE_LIRC_MODE2:
4543 ret = lirc_prog_attach(attr, prog);
4544 break;
4545 case BPF_PROG_TYPE_FLOW_DISSECTOR:
4546 ret = netns_bpf_prog_attach(attr, prog);
4547 break;
4548 case BPF_PROG_TYPE_SCHED_CLS:
4549 if (attr->attach_type == BPF_TCX_INGRESS ||
4550 attr->attach_type == BPF_TCX_EGRESS)
4551 ret = tcx_prog_attach(attr, prog);
4552 else
4553 ret = netkit_prog_attach(attr, prog);
4554 break;
4555 default:
4556 ret = -EINVAL;
4557 }
4558 out:
4559 if (ret)
4560 bpf_prog_put(prog);
4561 return ret;
4562 }
4563
4564 #define BPF_PROG_DETACH_LAST_FIELD expected_revision
4565
bpf_prog_detach(const union bpf_attr * attr)4566 static int bpf_prog_detach(const union bpf_attr *attr)
4567 {
4568 struct bpf_prog *prog = NULL;
4569 enum bpf_prog_type ptype;
4570 int ret;
4571
4572 if (CHECK_ATTR(BPF_PROG_DETACH))
4573 return -EINVAL;
4574
4575 ptype = attach_type_to_prog_type(attr->attach_type);
4576 if (bpf_mprog_supported(ptype)) {
4577 if (ptype == BPF_PROG_TYPE_UNSPEC)
4578 return -EINVAL;
4579 if (attr->attach_flags & ~BPF_F_ATTACH_MASK_MPROG)
4580 return -EINVAL;
4581 if (attr->attach_bpf_fd) {
4582 prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype);
4583 if (IS_ERR(prog))
4584 return PTR_ERR(prog);
4585 } else if (!bpf_mprog_detach_empty(ptype)) {
4586 return -EPERM;
4587 }
4588 } else if (is_cgroup_prog_type(ptype, 0, false)) {
4589 if (attr->attach_flags || attr->relative_fd)
4590 return -EINVAL;
4591 } else if (attr->attach_flags ||
4592 attr->relative_fd ||
4593 attr->expected_revision) {
4594 return -EINVAL;
4595 }
4596
4597 switch (ptype) {
4598 case BPF_PROG_TYPE_SK_MSG:
4599 case BPF_PROG_TYPE_SK_SKB:
4600 ret = sock_map_prog_detach(attr, ptype);
4601 break;
4602 case BPF_PROG_TYPE_LIRC_MODE2:
4603 ret = lirc_prog_detach(attr);
4604 break;
4605 case BPF_PROG_TYPE_FLOW_DISSECTOR:
4606 ret = netns_bpf_prog_detach(attr, ptype);
4607 break;
4608 case BPF_PROG_TYPE_CGROUP_DEVICE:
4609 case BPF_PROG_TYPE_CGROUP_SKB:
4610 case BPF_PROG_TYPE_CGROUP_SOCK:
4611 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
4612 case BPF_PROG_TYPE_CGROUP_SOCKOPT:
4613 case BPF_PROG_TYPE_CGROUP_SYSCTL:
4614 case BPF_PROG_TYPE_SOCK_OPS:
4615 case BPF_PROG_TYPE_LSM:
4616 ret = cgroup_bpf_prog_detach(attr, ptype);
4617 break;
4618 case BPF_PROG_TYPE_SCHED_CLS:
4619 if (attr->attach_type == BPF_TCX_INGRESS ||
4620 attr->attach_type == BPF_TCX_EGRESS)
4621 ret = tcx_prog_detach(attr, prog);
4622 else
4623 ret = netkit_prog_detach(attr, prog);
4624 break;
4625 default:
4626 ret = -EINVAL;
4627 }
4628
4629 if (prog)
4630 bpf_prog_put(prog);
4631 return ret;
4632 }
4633
4634 #define BPF_PROG_QUERY_LAST_FIELD query.revision
4635
bpf_prog_query(const union bpf_attr * attr,union bpf_attr __user * uattr)4636 static int bpf_prog_query(const union bpf_attr *attr,
4637 union bpf_attr __user *uattr)
4638 {
4639 if (!bpf_net_capable())
4640 return -EPERM;
4641 if (CHECK_ATTR(BPF_PROG_QUERY))
4642 return -EINVAL;
4643 if (attr->query.query_flags & ~BPF_F_QUERY_EFFECTIVE)
4644 return -EINVAL;
4645
4646 switch (attr->query.attach_type) {
4647 case BPF_CGROUP_INET_INGRESS:
4648 case BPF_CGROUP_INET_EGRESS:
4649 case BPF_CGROUP_INET_SOCK_CREATE:
4650 case BPF_CGROUP_INET_SOCK_RELEASE:
4651 case BPF_CGROUP_INET4_BIND:
4652 case BPF_CGROUP_INET6_BIND:
4653 case BPF_CGROUP_INET4_POST_BIND:
4654 case BPF_CGROUP_INET6_POST_BIND:
4655 case BPF_CGROUP_INET4_CONNECT:
4656 case BPF_CGROUP_INET6_CONNECT:
4657 case BPF_CGROUP_UNIX_CONNECT:
4658 case BPF_CGROUP_INET4_GETPEERNAME:
4659 case BPF_CGROUP_INET6_GETPEERNAME:
4660 case BPF_CGROUP_UNIX_GETPEERNAME:
4661 case BPF_CGROUP_INET4_GETSOCKNAME:
4662 case BPF_CGROUP_INET6_GETSOCKNAME:
4663 case BPF_CGROUP_UNIX_GETSOCKNAME:
4664 case BPF_CGROUP_UDP4_SENDMSG:
4665 case BPF_CGROUP_UDP6_SENDMSG:
4666 case BPF_CGROUP_UNIX_SENDMSG:
4667 case BPF_CGROUP_UDP4_RECVMSG:
4668 case BPF_CGROUP_UDP6_RECVMSG:
4669 case BPF_CGROUP_UNIX_RECVMSG:
4670 case BPF_CGROUP_SOCK_OPS:
4671 case BPF_CGROUP_DEVICE:
4672 case BPF_CGROUP_SYSCTL:
4673 case BPF_CGROUP_GETSOCKOPT:
4674 case BPF_CGROUP_SETSOCKOPT:
4675 case BPF_LSM_CGROUP:
4676 return cgroup_bpf_prog_query(attr, uattr);
4677 case BPF_LIRC_MODE2:
4678 return lirc_prog_query(attr, uattr);
4679 case BPF_FLOW_DISSECTOR:
4680 case BPF_SK_LOOKUP:
4681 return netns_bpf_prog_query(attr, uattr);
4682 case BPF_SK_SKB_STREAM_PARSER:
4683 case BPF_SK_SKB_STREAM_VERDICT:
4684 case BPF_SK_MSG_VERDICT:
4685 case BPF_SK_SKB_VERDICT:
4686 return sock_map_bpf_prog_query(attr, uattr);
4687 case BPF_TCX_INGRESS:
4688 case BPF_TCX_EGRESS:
4689 return tcx_prog_query(attr, uattr);
4690 case BPF_NETKIT_PRIMARY:
4691 case BPF_NETKIT_PEER:
4692 return netkit_prog_query(attr, uattr);
4693 default:
4694 return -EINVAL;
4695 }
4696 }
4697
4698 #define BPF_PROG_TEST_RUN_LAST_FIELD test.batch_size
4699
bpf_prog_test_run(const union bpf_attr * attr,union bpf_attr __user * uattr)4700 static int bpf_prog_test_run(const union bpf_attr *attr,
4701 union bpf_attr __user *uattr)
4702 {
4703 struct bpf_prog *prog;
4704 int ret = -ENOTSUPP;
4705
4706 if (CHECK_ATTR(BPF_PROG_TEST_RUN))
4707 return -EINVAL;
4708
4709 if ((attr->test.ctx_size_in && !attr->test.ctx_in) ||
4710 (!attr->test.ctx_size_in && attr->test.ctx_in))
4711 return -EINVAL;
4712
4713 if ((attr->test.ctx_size_out && !attr->test.ctx_out) ||
4714 (!attr->test.ctx_size_out && attr->test.ctx_out))
4715 return -EINVAL;
4716
4717 prog = bpf_prog_get(attr->test.prog_fd);
4718 if (IS_ERR(prog))
4719 return PTR_ERR(prog);
4720
4721 if (prog->aux->ops->test_run)
4722 ret = prog->aux->ops->test_run(prog, attr, uattr);
4723
4724 bpf_prog_put(prog);
4725 return ret;
4726 }
4727
4728 #define BPF_OBJ_GET_NEXT_ID_LAST_FIELD next_id
4729
bpf_obj_get_next_id(const union bpf_attr * attr,union bpf_attr __user * uattr,struct idr * idr,spinlock_t * lock)4730 static int bpf_obj_get_next_id(const union bpf_attr *attr,
4731 union bpf_attr __user *uattr,
4732 struct idr *idr,
4733 spinlock_t *lock)
4734 {
4735 u32 next_id = attr->start_id;
4736 int err = 0;
4737
4738 if (CHECK_ATTR(BPF_OBJ_GET_NEXT_ID) || next_id >= INT_MAX)
4739 return -EINVAL;
4740
4741 if (!capable(CAP_SYS_ADMIN))
4742 return -EPERM;
4743
4744 next_id++;
4745 spin_lock_bh(lock);
4746 if (!idr_get_next(idr, &next_id))
4747 err = -ENOENT;
4748 spin_unlock_bh(lock);
4749
4750 if (!err)
4751 err = put_user(next_id, &uattr->next_id);
4752
4753 return err;
4754 }
4755
bpf_map_get_curr_or_next(u32 * id)4756 struct bpf_map *bpf_map_get_curr_or_next(u32 *id)
4757 {
4758 struct bpf_map *map;
4759
4760 spin_lock_bh(&map_idr_lock);
4761 again:
4762 map = idr_get_next(&map_idr, id);
4763 if (map) {
4764 map = __bpf_map_inc_not_zero(map, false);
4765 if (IS_ERR(map)) {
4766 (*id)++;
4767 goto again;
4768 }
4769 }
4770 spin_unlock_bh(&map_idr_lock);
4771
4772 return map;
4773 }
4774
bpf_prog_get_curr_or_next(u32 * id)4775 struct bpf_prog *bpf_prog_get_curr_or_next(u32 *id)
4776 {
4777 struct bpf_prog *prog;
4778
4779 spin_lock_bh(&prog_idr_lock);
4780 again:
4781 prog = idr_get_next(&prog_idr, id);
4782 if (prog) {
4783 prog = bpf_prog_inc_not_zero(prog);
4784 if (IS_ERR(prog)) {
4785 (*id)++;
4786 goto again;
4787 }
4788 }
4789 spin_unlock_bh(&prog_idr_lock);
4790
4791 return prog;
4792 }
4793
4794 #define BPF_PROG_GET_FD_BY_ID_LAST_FIELD prog_id
4795
bpf_prog_by_id(u32 id)4796 struct bpf_prog *bpf_prog_by_id(u32 id)
4797 {
4798 struct bpf_prog *prog;
4799
4800 if (!id)
4801 return ERR_PTR(-ENOENT);
4802
4803 spin_lock_bh(&prog_idr_lock);
4804 prog = idr_find(&prog_idr, id);
4805 if (prog)
4806 prog = bpf_prog_inc_not_zero(prog);
4807 else
4808 prog = ERR_PTR(-ENOENT);
4809 spin_unlock_bh(&prog_idr_lock);
4810 return prog;
4811 }
4812
bpf_prog_get_fd_by_id(const union bpf_attr * attr)4813 static int bpf_prog_get_fd_by_id(const union bpf_attr *attr)
4814 {
4815 struct bpf_prog *prog;
4816 u32 id = attr->prog_id;
4817 int fd;
4818
4819 if (CHECK_ATTR(BPF_PROG_GET_FD_BY_ID))
4820 return -EINVAL;
4821
4822 if (!capable(CAP_SYS_ADMIN))
4823 return -EPERM;
4824
4825 prog = bpf_prog_by_id(id);
4826 if (IS_ERR(prog))
4827 return PTR_ERR(prog);
4828
4829 fd = bpf_prog_new_fd(prog);
4830 if (fd < 0)
4831 bpf_prog_put(prog);
4832
4833 return fd;
4834 }
4835
4836 #define BPF_MAP_GET_FD_BY_ID_LAST_FIELD open_flags
4837
bpf_map_get_fd_by_id(const union bpf_attr * attr)4838 static int bpf_map_get_fd_by_id(const union bpf_attr *attr)
4839 {
4840 struct bpf_map *map;
4841 u32 id = attr->map_id;
4842 int f_flags;
4843 int fd;
4844
4845 if (CHECK_ATTR(BPF_MAP_GET_FD_BY_ID) ||
4846 attr->open_flags & ~BPF_OBJ_FLAG_MASK)
4847 return -EINVAL;
4848
4849 if (!capable(CAP_SYS_ADMIN))
4850 return -EPERM;
4851
4852 f_flags = bpf_get_file_flag(attr->open_flags);
4853 if (f_flags < 0)
4854 return f_flags;
4855
4856 spin_lock_bh(&map_idr_lock);
4857 map = idr_find(&map_idr, id);
4858 if (map)
4859 map = __bpf_map_inc_not_zero(map, true);
4860 else
4861 map = ERR_PTR(-ENOENT);
4862 spin_unlock_bh(&map_idr_lock);
4863
4864 if (IS_ERR(map))
4865 return PTR_ERR(map);
4866
4867 fd = bpf_map_new_fd(map, f_flags);
4868 if (fd < 0)
4869 bpf_map_put_with_uref(map);
4870
4871 return fd;
4872 }
4873
bpf_map_from_imm(const struct bpf_prog * prog,unsigned long addr,u32 * off,u32 * type)4874 static const struct bpf_map *bpf_map_from_imm(const struct bpf_prog *prog,
4875 unsigned long addr, u32 *off,
4876 u32 *type)
4877 {
4878 const struct bpf_map *map;
4879 int i;
4880
4881 mutex_lock(&prog->aux->used_maps_mutex);
4882 for (i = 0, *off = 0; i < prog->aux->used_map_cnt; i++) {
4883 map = prog->aux->used_maps[i];
4884 if (map == (void *)addr) {
4885 *type = BPF_PSEUDO_MAP_FD;
4886 goto out;
4887 }
4888 if (!map->ops->map_direct_value_meta)
4889 continue;
4890 if (!map->ops->map_direct_value_meta(map, addr, off)) {
4891 *type = BPF_PSEUDO_MAP_VALUE;
4892 goto out;
4893 }
4894 }
4895 map = NULL;
4896
4897 out:
4898 mutex_unlock(&prog->aux->used_maps_mutex);
4899 return map;
4900 }
4901
bpf_insn_prepare_dump(const struct bpf_prog * prog,const struct cred * f_cred)4902 static struct bpf_insn *bpf_insn_prepare_dump(const struct bpf_prog *prog,
4903 const struct cred *f_cred)
4904 {
4905 const struct bpf_map *map;
4906 struct bpf_insn *insns;
4907 u32 off, type;
4908 u64 imm;
4909 u8 code;
4910 int i;
4911
4912 insns = kmemdup(prog->insnsi, bpf_prog_insn_size(prog),
4913 GFP_USER);
4914 if (!insns)
4915 return insns;
4916
4917 for (i = 0; i < prog->len; i++) {
4918 code = insns[i].code;
4919
4920 if (code == (BPF_JMP | BPF_TAIL_CALL)) {
4921 insns[i].code = BPF_JMP | BPF_CALL;
4922 insns[i].imm = BPF_FUNC_tail_call;
4923 /* fall-through */
4924 }
4925 if (code == (BPF_JMP | BPF_CALL) ||
4926 code == (BPF_JMP | BPF_CALL_ARGS)) {
4927 if (code == (BPF_JMP | BPF_CALL_ARGS))
4928 insns[i].code = BPF_JMP | BPF_CALL;
4929 if (!bpf_dump_raw_ok(f_cred))
4930 insns[i].imm = 0;
4931 continue;
4932 }
4933 if (BPF_CLASS(code) == BPF_LDX && BPF_MODE(code) == BPF_PROBE_MEM) {
4934 insns[i].code = BPF_LDX | BPF_SIZE(code) | BPF_MEM;
4935 continue;
4936 }
4937
4938 if ((BPF_CLASS(code) == BPF_LDX || BPF_CLASS(code) == BPF_STX ||
4939 BPF_CLASS(code) == BPF_ST) && BPF_MODE(code) == BPF_PROBE_MEM32) {
4940 insns[i].code = BPF_CLASS(code) | BPF_SIZE(code) | BPF_MEM;
4941 continue;
4942 }
4943
4944 if (code != (BPF_LD | BPF_IMM | BPF_DW))
4945 continue;
4946
4947 imm = ((u64)insns[i + 1].imm << 32) | (u32)insns[i].imm;
4948 map = bpf_map_from_imm(prog, imm, &off, &type);
4949 if (map) {
4950 insns[i].src_reg = type;
4951 insns[i].imm = map->id;
4952 insns[i + 1].imm = off;
4953 continue;
4954 }
4955 }
4956
4957 return insns;
4958 }
4959
set_info_rec_size(struct bpf_prog_info * info)4960 static int set_info_rec_size(struct bpf_prog_info *info)
4961 {
4962 /*
4963 * Ensure info.*_rec_size is the same as kernel expected size
4964 *
4965 * or
4966 *
4967 * Only allow zero *_rec_size if both _rec_size and _cnt are
4968 * zero. In this case, the kernel will set the expected
4969 * _rec_size back to the info.
4970 */
4971
4972 if ((info->nr_func_info || info->func_info_rec_size) &&
4973 info->func_info_rec_size != sizeof(struct bpf_func_info))
4974 return -EINVAL;
4975
4976 if ((info->nr_line_info || info->line_info_rec_size) &&
4977 info->line_info_rec_size != sizeof(struct bpf_line_info))
4978 return -EINVAL;
4979
4980 if ((info->nr_jited_line_info || info->jited_line_info_rec_size) &&
4981 info->jited_line_info_rec_size != sizeof(__u64))
4982 return -EINVAL;
4983
4984 info->func_info_rec_size = sizeof(struct bpf_func_info);
4985 info->line_info_rec_size = sizeof(struct bpf_line_info);
4986 info->jited_line_info_rec_size = sizeof(__u64);
4987
4988 return 0;
4989 }
4990
bpf_prog_get_info_by_fd(struct file * file,struct bpf_prog * prog,const union bpf_attr * attr,union bpf_attr __user * uattr)4991 static int bpf_prog_get_info_by_fd(struct file *file,
4992 struct bpf_prog *prog,
4993 const union bpf_attr *attr,
4994 union bpf_attr __user *uattr)
4995 {
4996 struct bpf_prog_info __user *uinfo = u64_to_user_ptr(attr->info.info);
4997 struct btf *attach_btf = bpf_prog_get_target_btf(prog);
4998 struct bpf_prog_info info;
4999 u32 info_len = attr->info.info_len;
5000 struct bpf_prog_kstats stats;
5001 char __user *uinsns;
5002 u32 ulen;
5003 int err;
5004
5005 err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len);
5006 if (err)
5007 return err;
5008 info_len = min_t(u32, sizeof(info), info_len);
5009
5010 memset(&info, 0, sizeof(info));
5011 if (copy_from_user(&info, uinfo, info_len))
5012 return -EFAULT;
5013
5014 info.type = prog->type;
5015 info.id = prog->aux->id;
5016 info.load_time = prog->aux->load_time;
5017 info.created_by_uid = from_kuid_munged(current_user_ns(),
5018 prog->aux->user->uid);
5019 info.gpl_compatible = prog->gpl_compatible;
5020
5021 memcpy(info.tag, prog->tag, sizeof(prog->tag));
5022 memcpy(info.name, prog->aux->name, sizeof(prog->aux->name));
5023
5024 mutex_lock(&prog->aux->used_maps_mutex);
5025 ulen = info.nr_map_ids;
5026 info.nr_map_ids = prog->aux->used_map_cnt;
5027 ulen = min_t(u32, info.nr_map_ids, ulen);
5028 if (ulen) {
5029 u32 __user *user_map_ids = u64_to_user_ptr(info.map_ids);
5030 u32 i;
5031
5032 for (i = 0; i < ulen; i++)
5033 if (put_user(prog->aux->used_maps[i]->id,
5034 &user_map_ids[i])) {
5035 mutex_unlock(&prog->aux->used_maps_mutex);
5036 return -EFAULT;
5037 }
5038 }
5039 mutex_unlock(&prog->aux->used_maps_mutex);
5040
5041 err = set_info_rec_size(&info);
5042 if (err)
5043 return err;
5044
5045 bpf_prog_get_stats(prog, &stats);
5046 info.run_time_ns = stats.nsecs;
5047 info.run_cnt = stats.cnt;
5048 info.recursion_misses = stats.misses;
5049
5050 info.verified_insns = prog->aux->verified_insns;
5051 if (prog->aux->btf)
5052 info.btf_id = btf_obj_id(prog->aux->btf);
5053
5054 if (!bpf_capable()) {
5055 info.jited_prog_len = 0;
5056 info.xlated_prog_len = 0;
5057 info.nr_jited_ksyms = 0;
5058 info.nr_jited_func_lens = 0;
5059 info.nr_func_info = 0;
5060 info.nr_line_info = 0;
5061 info.nr_jited_line_info = 0;
5062 goto done;
5063 }
5064
5065 ulen = info.xlated_prog_len;
5066 info.xlated_prog_len = bpf_prog_insn_size(prog);
5067 if (info.xlated_prog_len && ulen) {
5068 struct bpf_insn *insns_sanitized;
5069 bool fault;
5070
5071 if (!prog->blinded || bpf_dump_raw_ok(file->f_cred)) {
5072 insns_sanitized = bpf_insn_prepare_dump(prog, file->f_cred);
5073 if (!insns_sanitized)
5074 return -ENOMEM;
5075 uinsns = u64_to_user_ptr(info.xlated_prog_insns);
5076 ulen = min_t(u32, info.xlated_prog_len, ulen);
5077 fault = copy_to_user(uinsns, insns_sanitized, ulen);
5078 kfree(insns_sanitized);
5079 if (fault)
5080 return -EFAULT;
5081 } else {
5082 info.xlated_prog_insns = 0;
5083 }
5084 }
5085
5086 if (bpf_prog_is_offloaded(prog->aux)) {
5087 err = bpf_prog_offload_info_fill(&info, prog);
5088 if (err)
5089 return err;
5090 goto done;
5091 }
5092
5093 /* NOTE: the following code is supposed to be skipped for offload.
5094 * bpf_prog_offload_info_fill() is the place to fill similar fields
5095 * for offload.
5096 */
5097 ulen = info.jited_prog_len;
5098 if (prog->aux->func_cnt) {
5099 u32 i;
5100
5101 info.jited_prog_len = 0;
5102 for (i = 0; i < prog->aux->func_cnt; i++)
5103 info.jited_prog_len += prog->aux->func[i]->jited_len;
5104 } else {
5105 info.jited_prog_len = prog->jited_len;
5106 }
5107
5108 if (info.jited_prog_len && ulen) {
5109 if (bpf_dump_raw_ok(file->f_cred)) {
5110 uinsns = u64_to_user_ptr(info.jited_prog_insns);
5111 ulen = min_t(u32, info.jited_prog_len, ulen);
5112
5113 /* for multi-function programs, copy the JITed
5114 * instructions for all the functions
5115 */
5116 if (prog->aux->func_cnt) {
5117 u32 len, free, i;
5118 u8 *img;
5119
5120 free = ulen;
5121 for (i = 0; i < prog->aux->func_cnt; i++) {
5122 len = prog->aux->func[i]->jited_len;
5123 len = min_t(u32, len, free);
5124 img = (u8 *) prog->aux->func[i]->bpf_func;
5125 if (copy_to_user(uinsns, img, len))
5126 return -EFAULT;
5127 uinsns += len;
5128 free -= len;
5129 if (!free)
5130 break;
5131 }
5132 } else {
5133 if (copy_to_user(uinsns, prog->bpf_func, ulen))
5134 return -EFAULT;
5135 }
5136 } else {
5137 info.jited_prog_insns = 0;
5138 }
5139 }
5140
5141 ulen = info.nr_jited_ksyms;
5142 info.nr_jited_ksyms = prog->aux->func_cnt ? : 1;
5143 if (ulen) {
5144 if (bpf_dump_raw_ok(file->f_cred)) {
5145 unsigned long ksym_addr;
5146 u64 __user *user_ksyms;
5147 u32 i;
5148
5149 /* copy the address of the kernel symbol
5150 * corresponding to each function
5151 */
5152 ulen = min_t(u32, info.nr_jited_ksyms, ulen);
5153 user_ksyms = u64_to_user_ptr(info.jited_ksyms);
5154 if (prog->aux->func_cnt) {
5155 for (i = 0; i < ulen; i++) {
5156 ksym_addr = (unsigned long)
5157 prog->aux->func[i]->bpf_func;
5158 if (put_user((u64) ksym_addr,
5159 &user_ksyms[i]))
5160 return -EFAULT;
5161 }
5162 } else {
5163 ksym_addr = (unsigned long) prog->bpf_func;
5164 if (put_user((u64) ksym_addr, &user_ksyms[0]))
5165 return -EFAULT;
5166 }
5167 } else {
5168 info.jited_ksyms = 0;
5169 }
5170 }
5171
5172 ulen = info.nr_jited_func_lens;
5173 info.nr_jited_func_lens = prog->aux->func_cnt ? : 1;
5174 if (ulen) {
5175 if (bpf_dump_raw_ok(file->f_cred)) {
5176 u32 __user *user_lens;
5177 u32 func_len, i;
5178
5179 /* copy the JITed image lengths for each function */
5180 ulen = min_t(u32, info.nr_jited_func_lens, ulen);
5181 user_lens = u64_to_user_ptr(info.jited_func_lens);
5182 if (prog->aux->func_cnt) {
5183 for (i = 0; i < ulen; i++) {
5184 func_len =
5185 prog->aux->func[i]->jited_len;
5186 if (put_user(func_len, &user_lens[i]))
5187 return -EFAULT;
5188 }
5189 } else {
5190 func_len = prog->jited_len;
5191 if (put_user(func_len, &user_lens[0]))
5192 return -EFAULT;
5193 }
5194 } else {
5195 info.jited_func_lens = 0;
5196 }
5197 }
5198
5199 info.attach_btf_id = prog->aux->attach_btf_id;
5200 if (attach_btf)
5201 info.attach_btf_obj_id = btf_obj_id(attach_btf);
5202
5203 ulen = info.nr_func_info;
5204 info.nr_func_info = prog->aux->func_info_cnt;
5205 if (info.nr_func_info && ulen) {
5206 char __user *user_finfo;
5207
5208 user_finfo = u64_to_user_ptr(info.func_info);
5209 ulen = min_t(u32, info.nr_func_info, ulen);
5210 if (copy_to_user(user_finfo, prog->aux->func_info,
5211 info.func_info_rec_size * ulen))
5212 return -EFAULT;
5213 }
5214
5215 ulen = info.nr_line_info;
5216 info.nr_line_info = prog->aux->nr_linfo;
5217 if (info.nr_line_info && ulen) {
5218 __u8 __user *user_linfo;
5219
5220 user_linfo = u64_to_user_ptr(info.line_info);
5221 ulen = min_t(u32, info.nr_line_info, ulen);
5222 if (copy_to_user(user_linfo, prog->aux->linfo,
5223 info.line_info_rec_size * ulen))
5224 return -EFAULT;
5225 }
5226
5227 ulen = info.nr_jited_line_info;
5228 if (prog->aux->jited_linfo)
5229 info.nr_jited_line_info = prog->aux->nr_linfo;
5230 else
5231 info.nr_jited_line_info = 0;
5232 if (info.nr_jited_line_info && ulen) {
5233 if (bpf_dump_raw_ok(file->f_cred)) {
5234 unsigned long line_addr;
5235 __u64 __user *user_linfo;
5236 u32 i;
5237
5238 user_linfo = u64_to_user_ptr(info.jited_line_info);
5239 ulen = min_t(u32, info.nr_jited_line_info, ulen);
5240 for (i = 0; i < ulen; i++) {
5241 line_addr = (unsigned long)prog->aux->jited_linfo[i];
5242 if (put_user((__u64)line_addr, &user_linfo[i]))
5243 return -EFAULT;
5244 }
5245 } else {
5246 info.jited_line_info = 0;
5247 }
5248 }
5249
5250 ulen = info.nr_prog_tags;
5251 info.nr_prog_tags = prog->aux->func_cnt ? : 1;
5252 if (ulen) {
5253 __u8 __user (*user_prog_tags)[BPF_TAG_SIZE];
5254 u32 i;
5255
5256 user_prog_tags = u64_to_user_ptr(info.prog_tags);
5257 ulen = min_t(u32, info.nr_prog_tags, ulen);
5258 if (prog->aux->func_cnt) {
5259 for (i = 0; i < ulen; i++) {
5260 if (copy_to_user(user_prog_tags[i],
5261 prog->aux->func[i]->tag,
5262 BPF_TAG_SIZE))
5263 return -EFAULT;
5264 }
5265 } else {
5266 if (copy_to_user(user_prog_tags[0],
5267 prog->tag, BPF_TAG_SIZE))
5268 return -EFAULT;
5269 }
5270 }
5271
5272 done:
5273 if (copy_to_user(uinfo, &info, info_len) ||
5274 put_user(info_len, &uattr->info.info_len))
5275 return -EFAULT;
5276
5277 return 0;
5278 }
5279
bpf_map_get_info_by_fd(struct file * file,struct bpf_map * map,const union bpf_attr * attr,union bpf_attr __user * uattr)5280 static int bpf_map_get_info_by_fd(struct file *file,
5281 struct bpf_map *map,
5282 const union bpf_attr *attr,
5283 union bpf_attr __user *uattr)
5284 {
5285 struct bpf_map_info __user *uinfo = u64_to_user_ptr(attr->info.info);
5286 struct bpf_map_info info;
5287 u32 info_len = attr->info.info_len;
5288 int err;
5289
5290 err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len);
5291 if (err)
5292 return err;
5293 info_len = min_t(u32, sizeof(info), info_len);
5294
5295 memset(&info, 0, sizeof(info));
5296 if (copy_from_user(&info, uinfo, info_len))
5297 return -EFAULT;
5298
5299 info.type = map->map_type;
5300 info.id = map->id;
5301 info.key_size = map->key_size;
5302 info.value_size = map->value_size;
5303 info.max_entries = map->max_entries;
5304 info.map_flags = map->map_flags;
5305 info.map_extra = map->map_extra;
5306 memcpy(info.name, map->name, sizeof(map->name));
5307
5308 if (map->btf) {
5309 info.btf_id = btf_obj_id(map->btf);
5310 info.btf_key_type_id = map->btf_key_type_id;
5311 info.btf_value_type_id = map->btf_value_type_id;
5312 }
5313 info.btf_vmlinux_value_type_id = map->btf_vmlinux_value_type_id;
5314 if (map->map_type == BPF_MAP_TYPE_STRUCT_OPS)
5315 bpf_map_struct_ops_info_fill(&info, map);
5316
5317 if (bpf_map_is_offloaded(map)) {
5318 err = bpf_map_offload_info_fill(&info, map);
5319 if (err)
5320 return err;
5321 }
5322
5323 if (info.hash) {
5324 char __user *uhash = u64_to_user_ptr(info.hash);
5325
5326 if (!map->ops->map_get_hash)
5327 return -EINVAL;
5328
5329 if (info.hash_size != SHA256_DIGEST_SIZE)
5330 return -EINVAL;
5331
5332 if (!READ_ONCE(map->frozen))
5333 return -EPERM;
5334
5335 err = map->ops->map_get_hash(map, SHA256_DIGEST_SIZE, map->sha);
5336 if (err != 0)
5337 return err;
5338
5339 if (copy_to_user(uhash, map->sha, SHA256_DIGEST_SIZE) != 0)
5340 return -EFAULT;
5341 } else if (info.hash_size) {
5342 return -EINVAL;
5343 }
5344
5345 if (copy_to_user(uinfo, &info, info_len) ||
5346 put_user(info_len, &uattr->info.info_len))
5347 return -EFAULT;
5348
5349 return 0;
5350 }
5351
bpf_btf_get_info_by_fd(struct file * file,struct btf * btf,const union bpf_attr * attr,union bpf_attr __user * uattr)5352 static int bpf_btf_get_info_by_fd(struct file *file,
5353 struct btf *btf,
5354 const union bpf_attr *attr,
5355 union bpf_attr __user *uattr)
5356 {
5357 struct bpf_btf_info __user *uinfo = u64_to_user_ptr(attr->info.info);
5358 u32 info_len = attr->info.info_len;
5359 int err;
5360
5361 err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(*uinfo), info_len);
5362 if (err)
5363 return err;
5364
5365 return btf_get_info_by_fd(btf, attr, uattr);
5366 }
5367
bpf_link_get_info_by_fd(struct file * file,struct bpf_link * link,const union bpf_attr * attr,union bpf_attr __user * uattr)5368 static int bpf_link_get_info_by_fd(struct file *file,
5369 struct bpf_link *link,
5370 const union bpf_attr *attr,
5371 union bpf_attr __user *uattr)
5372 {
5373 struct bpf_link_info __user *uinfo = u64_to_user_ptr(attr->info.info);
5374 struct bpf_link_info info;
5375 u32 info_len = attr->info.info_len;
5376 int err;
5377
5378 err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(info), info_len);
5379 if (err)
5380 return err;
5381 info_len = min_t(u32, sizeof(info), info_len);
5382
5383 memset(&info, 0, sizeof(info));
5384 if (copy_from_user(&info, uinfo, info_len))
5385 return -EFAULT;
5386
5387 info.type = link->type;
5388 info.id = link->id;
5389 if (link->prog)
5390 info.prog_id = link->prog->aux->id;
5391
5392 if (link->ops->fill_link_info) {
5393 err = link->ops->fill_link_info(link, &info);
5394 if (err)
5395 return err;
5396 }
5397
5398 if (copy_to_user(uinfo, &info, info_len) ||
5399 put_user(info_len, &uattr->info.info_len))
5400 return -EFAULT;
5401
5402 return 0;
5403 }
5404
5405
token_get_info_by_fd(struct file * file,struct bpf_token * token,const union bpf_attr * attr,union bpf_attr __user * uattr)5406 static int token_get_info_by_fd(struct file *file,
5407 struct bpf_token *token,
5408 const union bpf_attr *attr,
5409 union bpf_attr __user *uattr)
5410 {
5411 struct bpf_token_info __user *uinfo = u64_to_user_ptr(attr->info.info);
5412 u32 info_len = attr->info.info_len;
5413 int err;
5414
5415 err = bpf_check_uarg_tail_zero(USER_BPFPTR(uinfo), sizeof(*uinfo), info_len);
5416 if (err)
5417 return err;
5418 return bpf_token_get_info_by_fd(token, attr, uattr);
5419 }
5420
5421 #define BPF_OBJ_GET_INFO_BY_FD_LAST_FIELD info.info
5422
bpf_obj_get_info_by_fd(const union bpf_attr * attr,union bpf_attr __user * uattr)5423 static int bpf_obj_get_info_by_fd(const union bpf_attr *attr,
5424 union bpf_attr __user *uattr)
5425 {
5426 if (CHECK_ATTR(BPF_OBJ_GET_INFO_BY_FD))
5427 return -EINVAL;
5428
5429 CLASS(fd, f)(attr->info.bpf_fd);
5430 if (fd_empty(f))
5431 return -EBADFD;
5432
5433 if (fd_file(f)->f_op == &bpf_prog_fops)
5434 return bpf_prog_get_info_by_fd(fd_file(f), fd_file(f)->private_data, attr,
5435 uattr);
5436 else if (fd_file(f)->f_op == &bpf_map_fops)
5437 return bpf_map_get_info_by_fd(fd_file(f), fd_file(f)->private_data, attr,
5438 uattr);
5439 else if (fd_file(f)->f_op == &btf_fops)
5440 return bpf_btf_get_info_by_fd(fd_file(f), fd_file(f)->private_data, attr, uattr);
5441 else if (fd_file(f)->f_op == &bpf_link_fops || fd_file(f)->f_op == &bpf_link_fops_poll)
5442 return bpf_link_get_info_by_fd(fd_file(f), fd_file(f)->private_data,
5443 attr, uattr);
5444 else if (fd_file(f)->f_op == &bpf_token_fops)
5445 return token_get_info_by_fd(fd_file(f), fd_file(f)->private_data,
5446 attr, uattr);
5447 return -EINVAL;
5448 }
5449
5450 #define BPF_BTF_LOAD_LAST_FIELD btf_token_fd
5451
bpf_btf_load(const union bpf_attr * attr,bpfptr_t uattr,__u32 uattr_size)5452 static int bpf_btf_load(const union bpf_attr *attr, bpfptr_t uattr, __u32 uattr_size)
5453 {
5454 struct bpf_token *token = NULL;
5455
5456 if (CHECK_ATTR(BPF_BTF_LOAD))
5457 return -EINVAL;
5458
5459 if (attr->btf_flags & ~BPF_F_TOKEN_FD)
5460 return -EINVAL;
5461
5462 if (attr->btf_flags & BPF_F_TOKEN_FD) {
5463 token = bpf_token_get_from_fd(attr->btf_token_fd);
5464 if (IS_ERR(token))
5465 return PTR_ERR(token);
5466 if (!bpf_token_allow_cmd(token, BPF_BTF_LOAD)) {
5467 bpf_token_put(token);
5468 token = NULL;
5469 }
5470 }
5471
5472 if (!bpf_token_capable(token, CAP_BPF)) {
5473 bpf_token_put(token);
5474 return -EPERM;
5475 }
5476
5477 bpf_token_put(token);
5478
5479 return btf_new_fd(attr, uattr, uattr_size);
5480 }
5481
5482 #define BPF_BTF_GET_FD_BY_ID_LAST_FIELD fd_by_id_token_fd
5483
bpf_btf_get_fd_by_id(const union bpf_attr * attr)5484 static int bpf_btf_get_fd_by_id(const union bpf_attr *attr)
5485 {
5486 struct bpf_token *token = NULL;
5487
5488 if (CHECK_ATTR(BPF_BTF_GET_FD_BY_ID))
5489 return -EINVAL;
5490
5491 if (attr->open_flags & ~BPF_F_TOKEN_FD)
5492 return -EINVAL;
5493
5494 if (attr->open_flags & BPF_F_TOKEN_FD) {
5495 token = bpf_token_get_from_fd(attr->fd_by_id_token_fd);
5496 if (IS_ERR(token))
5497 return PTR_ERR(token);
5498 if (!bpf_token_allow_cmd(token, BPF_BTF_GET_FD_BY_ID)) {
5499 bpf_token_put(token);
5500 token = NULL;
5501 }
5502 }
5503
5504 if (!bpf_token_capable(token, CAP_SYS_ADMIN)) {
5505 bpf_token_put(token);
5506 return -EPERM;
5507 }
5508
5509 bpf_token_put(token);
5510
5511 return btf_get_fd_by_id(attr->btf_id);
5512 }
5513
bpf_task_fd_query_copy(const union bpf_attr * attr,union bpf_attr __user * uattr,u32 prog_id,u32 fd_type,const char * buf,u64 probe_offset,u64 probe_addr)5514 static int bpf_task_fd_query_copy(const union bpf_attr *attr,
5515 union bpf_attr __user *uattr,
5516 u32 prog_id, u32 fd_type,
5517 const char *buf, u64 probe_offset,
5518 u64 probe_addr)
5519 {
5520 char __user *ubuf = u64_to_user_ptr(attr->task_fd_query.buf);
5521 u32 len = buf ? strlen(buf) : 0, input_len;
5522 int err = 0;
5523
5524 if (put_user(len, &uattr->task_fd_query.buf_len))
5525 return -EFAULT;
5526 input_len = attr->task_fd_query.buf_len;
5527 if (input_len && ubuf) {
5528 if (!len) {
5529 /* nothing to copy, just make ubuf NULL terminated */
5530 char zero = '\0';
5531
5532 if (put_user(zero, ubuf))
5533 return -EFAULT;
5534 } else {
5535 err = bpf_copy_to_user(ubuf, buf, input_len, len);
5536 if (err == -EFAULT)
5537 return err;
5538 }
5539 }
5540
5541 if (put_user(prog_id, &uattr->task_fd_query.prog_id) ||
5542 put_user(fd_type, &uattr->task_fd_query.fd_type) ||
5543 put_user(probe_offset, &uattr->task_fd_query.probe_offset) ||
5544 put_user(probe_addr, &uattr->task_fd_query.probe_addr))
5545 return -EFAULT;
5546
5547 return err;
5548 }
5549
5550 #define BPF_TASK_FD_QUERY_LAST_FIELD task_fd_query.probe_addr
5551
bpf_task_fd_query(const union bpf_attr * attr,union bpf_attr __user * uattr)5552 static int bpf_task_fd_query(const union bpf_attr *attr,
5553 union bpf_attr __user *uattr)
5554 {
5555 pid_t pid = attr->task_fd_query.pid;
5556 u32 fd = attr->task_fd_query.fd;
5557 const struct perf_event *event;
5558 struct task_struct *task;
5559 struct file *file;
5560 int err;
5561
5562 if (CHECK_ATTR(BPF_TASK_FD_QUERY))
5563 return -EINVAL;
5564
5565 if (!capable(CAP_SYS_ADMIN))
5566 return -EPERM;
5567
5568 if (attr->task_fd_query.flags != 0)
5569 return -EINVAL;
5570
5571 rcu_read_lock();
5572 task = get_pid_task(find_vpid(pid), PIDTYPE_PID);
5573 rcu_read_unlock();
5574 if (!task)
5575 return -ENOENT;
5576
5577 err = 0;
5578 file = fget_task(task, fd);
5579 put_task_struct(task);
5580 if (!file)
5581 return -EBADF;
5582
5583 if (file->f_op == &bpf_link_fops || file->f_op == &bpf_link_fops_poll) {
5584 struct bpf_link *link = file->private_data;
5585
5586 if (link->ops == &bpf_raw_tp_link_lops) {
5587 struct bpf_raw_tp_link *raw_tp =
5588 container_of(link, struct bpf_raw_tp_link, link);
5589 struct bpf_raw_event_map *btp = raw_tp->btp;
5590
5591 err = bpf_task_fd_query_copy(attr, uattr,
5592 raw_tp->link.prog->aux->id,
5593 BPF_FD_TYPE_RAW_TRACEPOINT,
5594 btp->tp->name, 0, 0);
5595 goto put_file;
5596 }
5597 goto out_not_supp;
5598 }
5599
5600 event = perf_get_event(file);
5601 if (!IS_ERR(event)) {
5602 u64 probe_offset, probe_addr;
5603 u32 prog_id, fd_type;
5604 const char *buf;
5605
5606 err = bpf_get_perf_event_info(event, &prog_id, &fd_type,
5607 &buf, &probe_offset,
5608 &probe_addr, NULL);
5609 if (!err)
5610 err = bpf_task_fd_query_copy(attr, uattr, prog_id,
5611 fd_type, buf,
5612 probe_offset,
5613 probe_addr);
5614 goto put_file;
5615 }
5616
5617 out_not_supp:
5618 err = -ENOTSUPP;
5619 put_file:
5620 fput(file);
5621 return err;
5622 }
5623
5624 #define BPF_MAP_BATCH_LAST_FIELD batch.flags
5625
5626 #define BPF_DO_BATCH(fn, ...) \
5627 do { \
5628 if (!fn) { \
5629 err = -ENOTSUPP; \
5630 goto err_put; \
5631 } \
5632 err = fn(__VA_ARGS__); \
5633 } while (0)
5634
bpf_map_do_batch(const union bpf_attr * attr,union bpf_attr __user * uattr,int cmd)5635 static int bpf_map_do_batch(const union bpf_attr *attr,
5636 union bpf_attr __user *uattr,
5637 int cmd)
5638 {
5639 bool has_read = cmd == BPF_MAP_LOOKUP_BATCH ||
5640 cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH;
5641 bool has_write = cmd != BPF_MAP_LOOKUP_BATCH;
5642 struct bpf_map *map;
5643 int err;
5644
5645 if (CHECK_ATTR(BPF_MAP_BATCH))
5646 return -EINVAL;
5647
5648 CLASS(fd, f)(attr->batch.map_fd);
5649
5650 map = __bpf_map_get(f);
5651 if (IS_ERR(map))
5652 return PTR_ERR(map);
5653 if (has_write)
5654 bpf_map_write_active_inc(map);
5655 if (has_read && !(map_get_sys_perms(map, f) & FMODE_CAN_READ)) {
5656 err = -EPERM;
5657 goto err_put;
5658 }
5659 if (has_write && !(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
5660 err = -EPERM;
5661 goto err_put;
5662 }
5663
5664 if (cmd == BPF_MAP_LOOKUP_BATCH)
5665 BPF_DO_BATCH(map->ops->map_lookup_batch, map, attr, uattr);
5666 else if (cmd == BPF_MAP_LOOKUP_AND_DELETE_BATCH)
5667 BPF_DO_BATCH(map->ops->map_lookup_and_delete_batch, map, attr, uattr);
5668 else if (cmd == BPF_MAP_UPDATE_BATCH)
5669 BPF_DO_BATCH(map->ops->map_update_batch, map, fd_file(f), attr, uattr);
5670 else
5671 BPF_DO_BATCH(map->ops->map_delete_batch, map, attr, uattr);
5672 err_put:
5673 if (has_write) {
5674 maybe_wait_bpf_programs(map);
5675 bpf_map_write_active_dec(map);
5676 }
5677 return err;
5678 }
5679
5680 #define BPF_LINK_CREATE_LAST_FIELD link_create.uprobe_multi.pid
link_create(union bpf_attr * attr,bpfptr_t uattr)5681 static int link_create(union bpf_attr *attr, bpfptr_t uattr)
5682 {
5683 struct bpf_prog *prog;
5684 int ret;
5685
5686 if (CHECK_ATTR(BPF_LINK_CREATE))
5687 return -EINVAL;
5688
5689 if (attr->link_create.attach_type == BPF_STRUCT_OPS)
5690 return bpf_struct_ops_link_create(attr);
5691
5692 prog = bpf_prog_get(attr->link_create.prog_fd);
5693 if (IS_ERR(prog))
5694 return PTR_ERR(prog);
5695
5696 ret = bpf_prog_attach_check_attach_type(prog,
5697 attr->link_create.attach_type);
5698 if (ret)
5699 goto out;
5700
5701 switch (prog->type) {
5702 case BPF_PROG_TYPE_CGROUP_SKB:
5703 case BPF_PROG_TYPE_CGROUP_SOCK:
5704 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
5705 case BPF_PROG_TYPE_SOCK_OPS:
5706 case BPF_PROG_TYPE_CGROUP_DEVICE:
5707 case BPF_PROG_TYPE_CGROUP_SYSCTL:
5708 case BPF_PROG_TYPE_CGROUP_SOCKOPT:
5709 ret = cgroup_bpf_link_attach(attr, prog);
5710 break;
5711 case BPF_PROG_TYPE_EXT:
5712 ret = bpf_tracing_prog_attach(prog,
5713 attr->link_create.target_fd,
5714 attr->link_create.target_btf_id,
5715 attr->link_create.tracing.cookie,
5716 attr->link_create.attach_type);
5717 break;
5718 case BPF_PROG_TYPE_LSM:
5719 case BPF_PROG_TYPE_TRACING:
5720 if (attr->link_create.attach_type != prog->expected_attach_type) {
5721 ret = -EINVAL;
5722 goto out;
5723 }
5724 if (prog->expected_attach_type == BPF_TRACE_RAW_TP)
5725 ret = bpf_raw_tp_link_attach(prog, NULL, attr->link_create.tracing.cookie,
5726 attr->link_create.attach_type);
5727 else if (prog->expected_attach_type == BPF_TRACE_ITER)
5728 ret = bpf_iter_link_attach(attr, uattr, prog);
5729 else if (prog->expected_attach_type == BPF_LSM_CGROUP)
5730 ret = cgroup_bpf_link_attach(attr, prog);
5731 else
5732 ret = bpf_tracing_prog_attach(prog,
5733 attr->link_create.target_fd,
5734 attr->link_create.target_btf_id,
5735 attr->link_create.tracing.cookie,
5736 attr->link_create.attach_type);
5737 break;
5738 case BPF_PROG_TYPE_FLOW_DISSECTOR:
5739 case BPF_PROG_TYPE_SK_LOOKUP:
5740 ret = netns_bpf_link_create(attr, prog);
5741 break;
5742 case BPF_PROG_TYPE_SK_MSG:
5743 case BPF_PROG_TYPE_SK_SKB:
5744 ret = sock_map_link_create(attr, prog);
5745 break;
5746 #ifdef CONFIG_NET
5747 case BPF_PROG_TYPE_XDP:
5748 ret = bpf_xdp_link_attach(attr, prog);
5749 break;
5750 case BPF_PROG_TYPE_SCHED_CLS:
5751 if (attr->link_create.attach_type == BPF_TCX_INGRESS ||
5752 attr->link_create.attach_type == BPF_TCX_EGRESS)
5753 ret = tcx_link_attach(attr, prog);
5754 else
5755 ret = netkit_link_attach(attr, prog);
5756 break;
5757 case BPF_PROG_TYPE_NETFILTER:
5758 ret = bpf_nf_link_attach(attr, prog);
5759 break;
5760 #endif
5761 case BPF_PROG_TYPE_PERF_EVENT:
5762 case BPF_PROG_TYPE_TRACEPOINT:
5763 ret = bpf_perf_link_attach(attr, prog);
5764 break;
5765 case BPF_PROG_TYPE_KPROBE:
5766 if (attr->link_create.attach_type == BPF_PERF_EVENT)
5767 ret = bpf_perf_link_attach(attr, prog);
5768 else if (attr->link_create.attach_type == BPF_TRACE_KPROBE_MULTI ||
5769 attr->link_create.attach_type == BPF_TRACE_KPROBE_SESSION)
5770 ret = bpf_kprobe_multi_link_attach(attr, prog);
5771 else if (attr->link_create.attach_type == BPF_TRACE_UPROBE_MULTI ||
5772 attr->link_create.attach_type == BPF_TRACE_UPROBE_SESSION)
5773 ret = bpf_uprobe_multi_link_attach(attr, prog);
5774 break;
5775 default:
5776 ret = -EINVAL;
5777 }
5778
5779 out:
5780 if (ret < 0)
5781 bpf_prog_put(prog);
5782 return ret;
5783 }
5784
link_update_map(struct bpf_link * link,union bpf_attr * attr)5785 static int link_update_map(struct bpf_link *link, union bpf_attr *attr)
5786 {
5787 struct bpf_map *new_map, *old_map = NULL;
5788 int ret;
5789
5790 new_map = bpf_map_get(attr->link_update.new_map_fd);
5791 if (IS_ERR(new_map))
5792 return PTR_ERR(new_map);
5793
5794 if (attr->link_update.flags & BPF_F_REPLACE) {
5795 old_map = bpf_map_get(attr->link_update.old_map_fd);
5796 if (IS_ERR(old_map)) {
5797 ret = PTR_ERR(old_map);
5798 goto out_put;
5799 }
5800 } else if (attr->link_update.old_map_fd) {
5801 ret = -EINVAL;
5802 goto out_put;
5803 }
5804
5805 ret = link->ops->update_map(link, new_map, old_map);
5806
5807 if (old_map)
5808 bpf_map_put(old_map);
5809 out_put:
5810 bpf_map_put(new_map);
5811 return ret;
5812 }
5813
5814 #define BPF_LINK_UPDATE_LAST_FIELD link_update.old_prog_fd
5815
link_update(union bpf_attr * attr)5816 static int link_update(union bpf_attr *attr)
5817 {
5818 struct bpf_prog *old_prog = NULL, *new_prog;
5819 struct bpf_link *link;
5820 u32 flags;
5821 int ret;
5822
5823 if (CHECK_ATTR(BPF_LINK_UPDATE))
5824 return -EINVAL;
5825
5826 flags = attr->link_update.flags;
5827 if (flags & ~BPF_F_REPLACE)
5828 return -EINVAL;
5829
5830 link = bpf_link_get_from_fd(attr->link_update.link_fd);
5831 if (IS_ERR(link))
5832 return PTR_ERR(link);
5833
5834 if (link->ops->update_map) {
5835 ret = link_update_map(link, attr);
5836 goto out_put_link;
5837 }
5838
5839 new_prog = bpf_prog_get(attr->link_update.new_prog_fd);
5840 if (IS_ERR(new_prog)) {
5841 ret = PTR_ERR(new_prog);
5842 goto out_put_link;
5843 }
5844
5845 if (flags & BPF_F_REPLACE) {
5846 old_prog = bpf_prog_get(attr->link_update.old_prog_fd);
5847 if (IS_ERR(old_prog)) {
5848 ret = PTR_ERR(old_prog);
5849 old_prog = NULL;
5850 goto out_put_progs;
5851 }
5852 } else if (attr->link_update.old_prog_fd) {
5853 ret = -EINVAL;
5854 goto out_put_progs;
5855 }
5856
5857 if (link->ops->update_prog)
5858 ret = link->ops->update_prog(link, new_prog, old_prog);
5859 else
5860 ret = -EINVAL;
5861
5862 out_put_progs:
5863 if (old_prog)
5864 bpf_prog_put(old_prog);
5865 if (ret)
5866 bpf_prog_put(new_prog);
5867 out_put_link:
5868 bpf_link_put_direct(link);
5869 return ret;
5870 }
5871
5872 #define BPF_LINK_DETACH_LAST_FIELD link_detach.link_fd
5873
link_detach(union bpf_attr * attr)5874 static int link_detach(union bpf_attr *attr)
5875 {
5876 struct bpf_link *link;
5877 int ret;
5878
5879 if (CHECK_ATTR(BPF_LINK_DETACH))
5880 return -EINVAL;
5881
5882 link = bpf_link_get_from_fd(attr->link_detach.link_fd);
5883 if (IS_ERR(link))
5884 return PTR_ERR(link);
5885
5886 if (link->ops->detach)
5887 ret = link->ops->detach(link);
5888 else
5889 ret = -EOPNOTSUPP;
5890
5891 bpf_link_put_direct(link);
5892 return ret;
5893 }
5894
bpf_link_inc_not_zero(struct bpf_link * link)5895 struct bpf_link *bpf_link_inc_not_zero(struct bpf_link *link)
5896 {
5897 return atomic64_fetch_add_unless(&link->refcnt, 1, 0) ? link : ERR_PTR(-ENOENT);
5898 }
5899 EXPORT_SYMBOL(bpf_link_inc_not_zero);
5900
bpf_link_by_id(u32 id)5901 struct bpf_link *bpf_link_by_id(u32 id)
5902 {
5903 struct bpf_link *link;
5904
5905 if (!id)
5906 return ERR_PTR(-ENOENT);
5907
5908 spin_lock_bh(&link_idr_lock);
5909 /* before link is "settled", ID is 0, pretend it doesn't exist yet */
5910 link = idr_find(&link_idr, id);
5911 if (link) {
5912 if (link->id)
5913 link = bpf_link_inc_not_zero(link);
5914 else
5915 link = ERR_PTR(-EAGAIN);
5916 } else {
5917 link = ERR_PTR(-ENOENT);
5918 }
5919 spin_unlock_bh(&link_idr_lock);
5920 return link;
5921 }
5922
bpf_link_get_curr_or_next(u32 * id)5923 struct bpf_link *bpf_link_get_curr_or_next(u32 *id)
5924 {
5925 struct bpf_link *link;
5926
5927 spin_lock_bh(&link_idr_lock);
5928 again:
5929 link = idr_get_next(&link_idr, id);
5930 if (link) {
5931 link = bpf_link_inc_not_zero(link);
5932 if (IS_ERR(link)) {
5933 (*id)++;
5934 goto again;
5935 }
5936 }
5937 spin_unlock_bh(&link_idr_lock);
5938
5939 return link;
5940 }
5941
5942 #define BPF_LINK_GET_FD_BY_ID_LAST_FIELD link_id
5943
bpf_link_get_fd_by_id(const union bpf_attr * attr)5944 static int bpf_link_get_fd_by_id(const union bpf_attr *attr)
5945 {
5946 struct bpf_link *link;
5947 u32 id = attr->link_id;
5948 int fd;
5949
5950 if (CHECK_ATTR(BPF_LINK_GET_FD_BY_ID))
5951 return -EINVAL;
5952
5953 if (!capable(CAP_SYS_ADMIN))
5954 return -EPERM;
5955
5956 link = bpf_link_by_id(id);
5957 if (IS_ERR(link))
5958 return PTR_ERR(link);
5959
5960 fd = bpf_link_new_fd(link);
5961 if (fd < 0)
5962 bpf_link_put_direct(link);
5963
5964 return fd;
5965 }
5966
5967 DEFINE_MUTEX(bpf_stats_enabled_mutex);
5968
bpf_stats_release(struct inode * inode,struct file * file)5969 static int bpf_stats_release(struct inode *inode, struct file *file)
5970 {
5971 mutex_lock(&bpf_stats_enabled_mutex);
5972 static_key_slow_dec(&bpf_stats_enabled_key.key);
5973 mutex_unlock(&bpf_stats_enabled_mutex);
5974 return 0;
5975 }
5976
5977 static const struct file_operations bpf_stats_fops = {
5978 .release = bpf_stats_release,
5979 };
5980
bpf_enable_runtime_stats(void)5981 static int bpf_enable_runtime_stats(void)
5982 {
5983 int fd;
5984
5985 mutex_lock(&bpf_stats_enabled_mutex);
5986
5987 /* Set a very high limit to avoid overflow */
5988 if (static_key_count(&bpf_stats_enabled_key.key) > INT_MAX / 2) {
5989 mutex_unlock(&bpf_stats_enabled_mutex);
5990 return -EBUSY;
5991 }
5992
5993 fd = anon_inode_getfd("bpf-stats", &bpf_stats_fops, NULL, O_CLOEXEC);
5994 if (fd >= 0)
5995 static_key_slow_inc(&bpf_stats_enabled_key.key);
5996
5997 mutex_unlock(&bpf_stats_enabled_mutex);
5998 return fd;
5999 }
6000
6001 #define BPF_ENABLE_STATS_LAST_FIELD enable_stats.type
6002
bpf_enable_stats(union bpf_attr * attr)6003 static int bpf_enable_stats(union bpf_attr *attr)
6004 {
6005
6006 if (CHECK_ATTR(BPF_ENABLE_STATS))
6007 return -EINVAL;
6008
6009 if (!capable(CAP_SYS_ADMIN))
6010 return -EPERM;
6011
6012 switch (attr->enable_stats.type) {
6013 case BPF_STATS_RUN_TIME:
6014 return bpf_enable_runtime_stats();
6015 default:
6016 break;
6017 }
6018 return -EINVAL;
6019 }
6020
6021 #define BPF_ITER_CREATE_LAST_FIELD iter_create.flags
6022
bpf_iter_create(union bpf_attr * attr)6023 static int bpf_iter_create(union bpf_attr *attr)
6024 {
6025 struct bpf_link *link;
6026 int err;
6027
6028 if (CHECK_ATTR(BPF_ITER_CREATE))
6029 return -EINVAL;
6030
6031 if (attr->iter_create.flags)
6032 return -EINVAL;
6033
6034 link = bpf_link_get_from_fd(attr->iter_create.link_fd);
6035 if (IS_ERR(link))
6036 return PTR_ERR(link);
6037
6038 err = bpf_iter_new_fd(link);
6039 bpf_link_put_direct(link);
6040
6041 return err;
6042 }
6043
6044 #define BPF_PROG_BIND_MAP_LAST_FIELD prog_bind_map.flags
6045
bpf_prog_bind_map(union bpf_attr * attr)6046 static int bpf_prog_bind_map(union bpf_attr *attr)
6047 {
6048 struct bpf_prog *prog;
6049 struct bpf_map *map;
6050 struct bpf_map **used_maps_old, **used_maps_new;
6051 int i, ret = 0;
6052
6053 if (CHECK_ATTR(BPF_PROG_BIND_MAP))
6054 return -EINVAL;
6055
6056 if (attr->prog_bind_map.flags)
6057 return -EINVAL;
6058
6059 prog = bpf_prog_get(attr->prog_bind_map.prog_fd);
6060 if (IS_ERR(prog))
6061 return PTR_ERR(prog);
6062
6063 map = bpf_map_get(attr->prog_bind_map.map_fd);
6064 if (IS_ERR(map)) {
6065 ret = PTR_ERR(map);
6066 goto out_prog_put;
6067 }
6068
6069 mutex_lock(&prog->aux->used_maps_mutex);
6070
6071 used_maps_old = prog->aux->used_maps;
6072
6073 for (i = 0; i < prog->aux->used_map_cnt; i++)
6074 if (used_maps_old[i] == map) {
6075 bpf_map_put(map);
6076 goto out_unlock;
6077 }
6078
6079 used_maps_new = kmalloc_objs(used_maps_new[0],
6080 prog->aux->used_map_cnt + 1);
6081 if (!used_maps_new) {
6082 ret = -ENOMEM;
6083 goto out_unlock;
6084 }
6085
6086 /* The bpf program will not access the bpf map, but for the sake of
6087 * simplicity, increase sleepable_refcnt for sleepable program as well.
6088 */
6089 if (prog->sleepable)
6090 atomic64_inc(&map->sleepable_refcnt);
6091 memcpy(used_maps_new, used_maps_old,
6092 sizeof(used_maps_old[0]) * prog->aux->used_map_cnt);
6093 used_maps_new[prog->aux->used_map_cnt] = map;
6094
6095 prog->aux->used_map_cnt++;
6096 prog->aux->used_maps = used_maps_new;
6097
6098 kfree(used_maps_old);
6099
6100 out_unlock:
6101 mutex_unlock(&prog->aux->used_maps_mutex);
6102
6103 if (ret)
6104 bpf_map_put(map);
6105 out_prog_put:
6106 bpf_prog_put(prog);
6107 return ret;
6108 }
6109
6110 #define BPF_TOKEN_CREATE_LAST_FIELD token_create.bpffs_fd
6111
token_create(union bpf_attr * attr)6112 static int token_create(union bpf_attr *attr)
6113 {
6114 if (CHECK_ATTR(BPF_TOKEN_CREATE))
6115 return -EINVAL;
6116
6117 /* no flags are supported yet */
6118 if (attr->token_create.flags)
6119 return -EINVAL;
6120
6121 return bpf_token_create(attr);
6122 }
6123
6124 #define BPF_PROG_STREAM_READ_BY_FD_LAST_FIELD prog_stream_read.prog_fd
6125
prog_stream_read(union bpf_attr * attr)6126 static int prog_stream_read(union bpf_attr *attr)
6127 {
6128 char __user *buf = u64_to_user_ptr(attr->prog_stream_read.stream_buf);
6129 u32 len = attr->prog_stream_read.stream_buf_len;
6130 struct bpf_prog *prog;
6131 int ret;
6132
6133 if (CHECK_ATTR(BPF_PROG_STREAM_READ_BY_FD))
6134 return -EINVAL;
6135
6136 prog = bpf_prog_get(attr->prog_stream_read.prog_fd);
6137 if (IS_ERR(prog))
6138 return PTR_ERR(prog);
6139
6140 ret = bpf_prog_stream_read(prog, attr->prog_stream_read.stream_id, buf, len);
6141 bpf_prog_put(prog);
6142
6143 return ret;
6144 }
6145
6146 #define BPF_PROG_ASSOC_STRUCT_OPS_LAST_FIELD prog_assoc_struct_ops.prog_fd
6147
prog_assoc_struct_ops(union bpf_attr * attr)6148 static int prog_assoc_struct_ops(union bpf_attr *attr)
6149 {
6150 struct bpf_prog *prog;
6151 struct bpf_map *map;
6152 int ret;
6153
6154 if (CHECK_ATTR(BPF_PROG_ASSOC_STRUCT_OPS))
6155 return -EINVAL;
6156
6157 if (attr->prog_assoc_struct_ops.flags)
6158 return -EINVAL;
6159
6160 prog = bpf_prog_get(attr->prog_assoc_struct_ops.prog_fd);
6161 if (IS_ERR(prog))
6162 return PTR_ERR(prog);
6163
6164 if (prog->type == BPF_PROG_TYPE_STRUCT_OPS) {
6165 ret = -EINVAL;
6166 goto put_prog;
6167 }
6168
6169 map = bpf_map_get(attr->prog_assoc_struct_ops.map_fd);
6170 if (IS_ERR(map)) {
6171 ret = PTR_ERR(map);
6172 goto put_prog;
6173 }
6174
6175 if (map->map_type != BPF_MAP_TYPE_STRUCT_OPS) {
6176 ret = -EINVAL;
6177 goto put_map;
6178 }
6179
6180 ret = bpf_prog_assoc_struct_ops(prog, map);
6181
6182 put_map:
6183 bpf_map_put(map);
6184 put_prog:
6185 bpf_prog_put(prog);
6186 return ret;
6187 }
6188
__sys_bpf(enum bpf_cmd cmd,bpfptr_t uattr,unsigned int size)6189 static int __sys_bpf(enum bpf_cmd cmd, bpfptr_t uattr, unsigned int size)
6190 {
6191 union bpf_attr attr;
6192 int err;
6193
6194 err = bpf_check_uarg_tail_zero(uattr, sizeof(attr), size);
6195 if (err)
6196 return err;
6197 size = min_t(u32, size, sizeof(attr));
6198
6199 /* copy attributes from user space, may be less than sizeof(bpf_attr) */
6200 memset(&attr, 0, sizeof(attr));
6201 if (copy_from_bpfptr(&attr, uattr, size) != 0)
6202 return -EFAULT;
6203
6204 err = security_bpf(cmd, &attr, size, uattr.is_kernel);
6205 if (err < 0)
6206 return err;
6207
6208 switch (cmd) {
6209 case BPF_MAP_CREATE:
6210 err = map_create(&attr, uattr);
6211 break;
6212 case BPF_MAP_LOOKUP_ELEM:
6213 err = map_lookup_elem(&attr);
6214 break;
6215 case BPF_MAP_UPDATE_ELEM:
6216 err = map_update_elem(&attr, uattr);
6217 break;
6218 case BPF_MAP_DELETE_ELEM:
6219 err = map_delete_elem(&attr, uattr);
6220 break;
6221 case BPF_MAP_GET_NEXT_KEY:
6222 err = map_get_next_key(&attr);
6223 break;
6224 case BPF_MAP_FREEZE:
6225 err = map_freeze(&attr);
6226 break;
6227 case BPF_PROG_LOAD:
6228 err = bpf_prog_load(&attr, uattr, size);
6229 break;
6230 case BPF_OBJ_PIN:
6231 err = bpf_obj_pin(&attr);
6232 break;
6233 case BPF_OBJ_GET:
6234 err = bpf_obj_get(&attr);
6235 break;
6236 case BPF_PROG_ATTACH:
6237 err = bpf_prog_attach(&attr);
6238 break;
6239 case BPF_PROG_DETACH:
6240 err = bpf_prog_detach(&attr);
6241 break;
6242 case BPF_PROG_QUERY:
6243 err = bpf_prog_query(&attr, uattr.user);
6244 break;
6245 case BPF_PROG_TEST_RUN:
6246 err = bpf_prog_test_run(&attr, uattr.user);
6247 break;
6248 case BPF_PROG_GET_NEXT_ID:
6249 err = bpf_obj_get_next_id(&attr, uattr.user,
6250 &prog_idr, &prog_idr_lock);
6251 break;
6252 case BPF_MAP_GET_NEXT_ID:
6253 err = bpf_obj_get_next_id(&attr, uattr.user,
6254 &map_idr, &map_idr_lock);
6255 break;
6256 case BPF_BTF_GET_NEXT_ID:
6257 err = bpf_obj_get_next_id(&attr, uattr.user,
6258 &btf_idr, &btf_idr_lock);
6259 break;
6260 case BPF_PROG_GET_FD_BY_ID:
6261 err = bpf_prog_get_fd_by_id(&attr);
6262 break;
6263 case BPF_MAP_GET_FD_BY_ID:
6264 err = bpf_map_get_fd_by_id(&attr);
6265 break;
6266 case BPF_OBJ_GET_INFO_BY_FD:
6267 err = bpf_obj_get_info_by_fd(&attr, uattr.user);
6268 break;
6269 case BPF_RAW_TRACEPOINT_OPEN:
6270 err = bpf_raw_tracepoint_open(&attr);
6271 break;
6272 case BPF_BTF_LOAD:
6273 err = bpf_btf_load(&attr, uattr, size);
6274 break;
6275 case BPF_BTF_GET_FD_BY_ID:
6276 err = bpf_btf_get_fd_by_id(&attr);
6277 break;
6278 case BPF_TASK_FD_QUERY:
6279 err = bpf_task_fd_query(&attr, uattr.user);
6280 break;
6281 case BPF_MAP_LOOKUP_AND_DELETE_ELEM:
6282 err = map_lookup_and_delete_elem(&attr);
6283 break;
6284 case BPF_MAP_LOOKUP_BATCH:
6285 err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_LOOKUP_BATCH);
6286 break;
6287 case BPF_MAP_LOOKUP_AND_DELETE_BATCH:
6288 err = bpf_map_do_batch(&attr, uattr.user,
6289 BPF_MAP_LOOKUP_AND_DELETE_BATCH);
6290 break;
6291 case BPF_MAP_UPDATE_BATCH:
6292 err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_UPDATE_BATCH);
6293 break;
6294 case BPF_MAP_DELETE_BATCH:
6295 err = bpf_map_do_batch(&attr, uattr.user, BPF_MAP_DELETE_BATCH);
6296 break;
6297 case BPF_LINK_CREATE:
6298 err = link_create(&attr, uattr);
6299 break;
6300 case BPF_LINK_UPDATE:
6301 err = link_update(&attr);
6302 break;
6303 case BPF_LINK_GET_FD_BY_ID:
6304 err = bpf_link_get_fd_by_id(&attr);
6305 break;
6306 case BPF_LINK_GET_NEXT_ID:
6307 err = bpf_obj_get_next_id(&attr, uattr.user,
6308 &link_idr, &link_idr_lock);
6309 break;
6310 case BPF_ENABLE_STATS:
6311 err = bpf_enable_stats(&attr);
6312 break;
6313 case BPF_ITER_CREATE:
6314 err = bpf_iter_create(&attr);
6315 break;
6316 case BPF_LINK_DETACH:
6317 err = link_detach(&attr);
6318 break;
6319 case BPF_PROG_BIND_MAP:
6320 err = bpf_prog_bind_map(&attr);
6321 break;
6322 case BPF_TOKEN_CREATE:
6323 err = token_create(&attr);
6324 break;
6325 case BPF_PROG_STREAM_READ_BY_FD:
6326 err = prog_stream_read(&attr);
6327 break;
6328 case BPF_PROG_ASSOC_STRUCT_OPS:
6329 err = prog_assoc_struct_ops(&attr);
6330 break;
6331 default:
6332 err = -EINVAL;
6333 break;
6334 }
6335
6336 return err;
6337 }
6338
SYSCALL_DEFINE3(bpf,int,cmd,union bpf_attr __user *,uattr,unsigned int,size)6339 SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size)
6340 {
6341 return __sys_bpf(cmd, USER_BPFPTR(uattr), size);
6342 }
6343
syscall_prog_is_valid_access(int off,int size,enum bpf_access_type type,const struct bpf_prog * prog,struct bpf_insn_access_aux * info)6344 static bool syscall_prog_is_valid_access(int off, int size,
6345 enum bpf_access_type type,
6346 const struct bpf_prog *prog,
6347 struct bpf_insn_access_aux *info)
6348 {
6349 if (off < 0 || off >= U16_MAX)
6350 return false;
6351 if (off % size != 0)
6352 return false;
6353 return true;
6354 }
6355
BPF_CALL_3(bpf_sys_bpf,int,cmd,union bpf_attr *,attr,u32,attr_size)6356 BPF_CALL_3(bpf_sys_bpf, int, cmd, union bpf_attr *, attr, u32, attr_size)
6357 {
6358 switch (cmd) {
6359 case BPF_MAP_CREATE:
6360 case BPF_MAP_DELETE_ELEM:
6361 case BPF_MAP_UPDATE_ELEM:
6362 case BPF_MAP_FREEZE:
6363 case BPF_MAP_GET_FD_BY_ID:
6364 case BPF_PROG_LOAD:
6365 case BPF_BTF_LOAD:
6366 case BPF_LINK_CREATE:
6367 case BPF_RAW_TRACEPOINT_OPEN:
6368 break;
6369 default:
6370 return -EINVAL;
6371 }
6372 return __sys_bpf(cmd, KERNEL_BPFPTR(attr), attr_size);
6373 }
6374
6375
6376 /* To shut up -Wmissing-prototypes.
6377 * This function is used by the kernel light skeleton
6378 * to load bpf programs when modules are loaded or during kernel boot.
6379 * See tools/lib/bpf/skel_internal.h
6380 */
6381 int kern_sys_bpf(int cmd, union bpf_attr *attr, unsigned int size);
6382
kern_sys_bpf(int cmd,union bpf_attr * attr,unsigned int size)6383 int kern_sys_bpf(int cmd, union bpf_attr *attr, unsigned int size)
6384 {
6385 struct bpf_prog * __maybe_unused prog;
6386 struct bpf_tramp_run_ctx __maybe_unused run_ctx;
6387
6388 switch (cmd) {
6389 #ifdef CONFIG_BPF_JIT /* __bpf_prog_enter_sleepable used by trampoline and JIT */
6390 case BPF_PROG_TEST_RUN:
6391 if (attr->test.data_in || attr->test.data_out ||
6392 attr->test.ctx_out || attr->test.duration ||
6393 attr->test.repeat || attr->test.flags)
6394 return -EINVAL;
6395
6396 prog = bpf_prog_get_type(attr->test.prog_fd, BPF_PROG_TYPE_SYSCALL);
6397 if (IS_ERR(prog))
6398 return PTR_ERR(prog);
6399
6400 if (attr->test.ctx_size_in < prog->aux->max_ctx_offset ||
6401 attr->test.ctx_size_in > U16_MAX) {
6402 bpf_prog_put(prog);
6403 return -EINVAL;
6404 }
6405
6406 run_ctx.bpf_cookie = 0;
6407 if (!__bpf_prog_enter_sleepable_recur(prog, &run_ctx)) {
6408 /* recursion detected */
6409 __bpf_prog_exit_sleepable_recur(prog, 0, &run_ctx);
6410 bpf_prog_put(prog);
6411 return -EBUSY;
6412 }
6413 attr->test.retval = bpf_prog_run(prog, (void *) (long) attr->test.ctx_in);
6414 __bpf_prog_exit_sleepable_recur(prog, 0 /* bpf_prog_run does runtime stats */,
6415 &run_ctx);
6416 bpf_prog_put(prog);
6417 return 0;
6418 #endif
6419 default:
6420 return ____bpf_sys_bpf(cmd, attr, size);
6421 }
6422 }
6423 EXPORT_SYMBOL_NS(kern_sys_bpf, "BPF_INTERNAL");
6424
6425 static const struct bpf_func_proto bpf_sys_bpf_proto = {
6426 .func = bpf_sys_bpf,
6427 .gpl_only = false,
6428 .ret_type = RET_INTEGER,
6429 .arg1_type = ARG_ANYTHING,
6430 .arg2_type = ARG_PTR_TO_MEM | MEM_RDONLY,
6431 .arg3_type = ARG_CONST_SIZE,
6432 };
6433
6434 const struct bpf_func_proto * __weak
tracing_prog_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)6435 tracing_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
6436 {
6437 return bpf_base_func_proto(func_id, prog);
6438 }
6439
BPF_CALL_1(bpf_sys_close,u32,fd)6440 BPF_CALL_1(bpf_sys_close, u32, fd)
6441 {
6442 /* When bpf program calls this helper there should not be
6443 * an fdget() without matching completed fdput().
6444 * This helper is allowed in the following callchain only:
6445 * sys_bpf->prog_test_run->bpf_prog->bpf_sys_close
6446 */
6447 return close_fd(fd);
6448 }
6449
6450 static const struct bpf_func_proto bpf_sys_close_proto = {
6451 .func = bpf_sys_close,
6452 .gpl_only = false,
6453 .ret_type = RET_INTEGER,
6454 .arg1_type = ARG_ANYTHING,
6455 };
6456
BPF_CALL_4(bpf_kallsyms_lookup_name,const char *,name,int,name_sz,int,flags,u64 *,res)6457 BPF_CALL_4(bpf_kallsyms_lookup_name, const char *, name, int, name_sz, int, flags, u64 *, res)
6458 {
6459 *res = 0;
6460 if (flags)
6461 return -EINVAL;
6462
6463 if (name_sz <= 1 || name[name_sz - 1])
6464 return -EINVAL;
6465
6466 if (!bpf_dump_raw_ok(current_cred()))
6467 return -EPERM;
6468
6469 *res = kallsyms_lookup_name(name);
6470 return *res ? 0 : -ENOENT;
6471 }
6472
6473 static const struct bpf_func_proto bpf_kallsyms_lookup_name_proto = {
6474 .func = bpf_kallsyms_lookup_name,
6475 .gpl_only = false,
6476 .ret_type = RET_INTEGER,
6477 .arg1_type = ARG_PTR_TO_MEM | MEM_RDONLY,
6478 .arg2_type = ARG_CONST_SIZE_OR_ZERO,
6479 .arg3_type = ARG_ANYTHING,
6480 .arg4_type = ARG_PTR_TO_FIXED_SIZE_MEM | MEM_UNINIT | MEM_WRITE | MEM_ALIGNED,
6481 .arg4_size = sizeof(u64),
6482 };
6483
6484 static const struct bpf_func_proto *
syscall_prog_func_proto(enum bpf_func_id func_id,const struct bpf_prog * prog)6485 syscall_prog_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
6486 {
6487 switch (func_id) {
6488 case BPF_FUNC_sys_bpf:
6489 return !bpf_token_capable(prog->aux->token, CAP_PERFMON)
6490 ? NULL : &bpf_sys_bpf_proto;
6491 case BPF_FUNC_btf_find_by_name_kind:
6492 return &bpf_btf_find_by_name_kind_proto;
6493 case BPF_FUNC_sys_close:
6494 return &bpf_sys_close_proto;
6495 case BPF_FUNC_kallsyms_lookup_name:
6496 return &bpf_kallsyms_lookup_name_proto;
6497 default:
6498 return tracing_prog_func_proto(func_id, prog);
6499 }
6500 }
6501
6502 const struct bpf_verifier_ops bpf_syscall_verifier_ops = {
6503 .get_func_proto = syscall_prog_func_proto,
6504 .is_valid_access = syscall_prog_is_valid_access,
6505 };
6506
6507 const struct bpf_prog_ops bpf_syscall_prog_ops = {
6508 .test_run = bpf_prog_test_run_syscall,
6509 };
6510
6511 #ifdef CONFIG_SYSCTL
bpf_stats_handler(const struct ctl_table * table,int write,void * buffer,size_t * lenp,loff_t * ppos)6512 static int bpf_stats_handler(const struct ctl_table *table, int write,
6513 void *buffer, size_t *lenp, loff_t *ppos)
6514 {
6515 struct static_key *key = (struct static_key *)table->data;
6516 static int saved_val;
6517 int val, ret;
6518 struct ctl_table tmp = {
6519 .data = &val,
6520 .maxlen = sizeof(val),
6521 .mode = table->mode,
6522 .extra1 = SYSCTL_ZERO,
6523 .extra2 = SYSCTL_ONE,
6524 };
6525
6526 if (write && !capable(CAP_SYS_ADMIN))
6527 return -EPERM;
6528
6529 mutex_lock(&bpf_stats_enabled_mutex);
6530 val = saved_val;
6531 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
6532 if (write && !ret && val != saved_val) {
6533 if (val)
6534 static_key_slow_inc(key);
6535 else
6536 static_key_slow_dec(key);
6537 saved_val = val;
6538 }
6539 mutex_unlock(&bpf_stats_enabled_mutex);
6540 return ret;
6541 }
6542
unpriv_ebpf_notify(int new_state)6543 void __weak unpriv_ebpf_notify(int new_state)
6544 {
6545 }
6546
bpf_unpriv_handler(const struct ctl_table * table,int write,void * buffer,size_t * lenp,loff_t * ppos)6547 static int bpf_unpriv_handler(const struct ctl_table *table, int write,
6548 void *buffer, size_t *lenp, loff_t *ppos)
6549 {
6550 int ret, unpriv_enable = *(int *)table->data;
6551 bool locked_state = unpriv_enable == 1;
6552 struct ctl_table tmp = *table;
6553
6554 if (write && !capable(CAP_SYS_ADMIN))
6555 return -EPERM;
6556
6557 tmp.data = &unpriv_enable;
6558 ret = proc_dointvec_minmax(&tmp, write, buffer, lenp, ppos);
6559 if (write && !ret) {
6560 if (locked_state && unpriv_enable != 1)
6561 return -EPERM;
6562 *(int *)table->data = unpriv_enable;
6563 }
6564
6565 if (write)
6566 unpriv_ebpf_notify(unpriv_enable);
6567
6568 return ret;
6569 }
6570
6571 static const struct ctl_table bpf_syscall_table[] = {
6572 {
6573 .procname = "unprivileged_bpf_disabled",
6574 .data = &sysctl_unprivileged_bpf_disabled,
6575 .maxlen = sizeof(sysctl_unprivileged_bpf_disabled),
6576 .mode = 0644,
6577 .proc_handler = bpf_unpriv_handler,
6578 .extra1 = SYSCTL_ZERO,
6579 .extra2 = SYSCTL_TWO,
6580 },
6581 {
6582 .procname = "bpf_stats_enabled",
6583 .data = &bpf_stats_enabled_key.key,
6584 .mode = 0644,
6585 .proc_handler = bpf_stats_handler,
6586 },
6587 };
6588
bpf_syscall_sysctl_init(void)6589 static int __init bpf_syscall_sysctl_init(void)
6590 {
6591 register_sysctl_init("kernel", bpf_syscall_table);
6592 return 0;
6593 }
6594 late_initcall(bpf_syscall_sysctl_init);
6595 #endif /* CONFIG_SYSCTL */
6596