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