Commit | Line | Data |
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99c55f7d AS |
1 | /* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com |
2 | * | |
3 | * This program is free software; you can redistribute it and/or | |
4 | * modify it under the terms of version 2 of the GNU General Public | |
5 | * License as published by the Free Software Foundation. | |
6 | * | |
7 | * This program is distributed in the hope that it will be useful, but | |
8 | * WITHOUT ANY WARRANTY; without even the implied warranty of | |
9 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU | |
10 | * General Public License for more details. | |
11 | */ | |
12 | #include <linux/bpf.h> | |
a67edbf4 | 13 | #include <linux/bpf_trace.h> |
99c55f7d AS |
14 | #include <linux/syscalls.h> |
15 | #include <linux/slab.h> | |
3f07c014 | 16 | #include <linux/sched/signal.h> |
d407bd25 DB |
17 | #include <linux/vmalloc.h> |
18 | #include <linux/mmzone.h> | |
99c55f7d | 19 | #include <linux/anon_inodes.h> |
db20fd2b | 20 | #include <linux/file.h> |
09756af4 AS |
21 | #include <linux/license.h> |
22 | #include <linux/filter.h> | |
2541517c | 23 | #include <linux/version.h> |
535e7b4b | 24 | #include <linux/kernel.h> |
dc4bb0e2 | 25 | #include <linux/idr.h> |
99c55f7d | 26 | |
b121d1e7 | 27 | DEFINE_PER_CPU(int, bpf_prog_active); |
dc4bb0e2 MKL |
28 | static DEFINE_IDR(prog_idr); |
29 | static DEFINE_SPINLOCK(prog_idr_lock); | |
f3f1c054 MKL |
30 | static DEFINE_IDR(map_idr); |
31 | static DEFINE_SPINLOCK(map_idr_lock); | |
b121d1e7 | 32 | |
1be7f75d AS |
33 | int sysctl_unprivileged_bpf_disabled __read_mostly; |
34 | ||
40077e0c JB |
35 | static const struct bpf_map_ops * const bpf_map_types[] = { |
36 | #define BPF_PROG_TYPE(_id, _ops) | |
37 | #define BPF_MAP_TYPE(_id, _ops) \ | |
38 | [_id] = &_ops, | |
39 | #include <linux/bpf_types.h> | |
40 | #undef BPF_PROG_TYPE | |
41 | #undef BPF_MAP_TYPE | |
42 | }; | |
99c55f7d AS |
43 | |
44 | static struct bpf_map *find_and_alloc_map(union bpf_attr *attr) | |
45 | { | |
99c55f7d AS |
46 | struct bpf_map *map; |
47 | ||
40077e0c JB |
48 | if (attr->map_type >= ARRAY_SIZE(bpf_map_types) || |
49 | !bpf_map_types[attr->map_type]) | |
50 | return ERR_PTR(-EINVAL); | |
99c55f7d | 51 | |
40077e0c JB |
52 | map = bpf_map_types[attr->map_type]->map_alloc(attr); |
53 | if (IS_ERR(map)) | |
54 | return map; | |
55 | map->ops = bpf_map_types[attr->map_type]; | |
56 | map->map_type = attr->map_type; | |
57 | return map; | |
99c55f7d AS |
58 | } |
59 | ||
d407bd25 DB |
60 | void *bpf_map_area_alloc(size_t size) |
61 | { | |
62 | /* We definitely need __GFP_NORETRY, so OOM killer doesn't | |
63 | * trigger under memory pressure as we really just want to | |
64 | * fail instead. | |
65 | */ | |
66 | const gfp_t flags = __GFP_NOWARN | __GFP_NORETRY | __GFP_ZERO; | |
67 | void *area; | |
68 | ||
69 | if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) { | |
70 | area = kmalloc(size, GFP_USER | flags); | |
71 | if (area != NULL) | |
72 | return area; | |
73 | } | |
74 | ||
19809c2d | 75 | return __vmalloc(size, GFP_KERNEL | flags, PAGE_KERNEL); |
d407bd25 DB |
76 | } |
77 | ||
78 | void bpf_map_area_free(void *area) | |
79 | { | |
80 | kvfree(area); | |
81 | } | |
82 | ||
6c905981 AS |
83 | int bpf_map_precharge_memlock(u32 pages) |
84 | { | |
85 | struct user_struct *user = get_current_user(); | |
86 | unsigned long memlock_limit, cur; | |
87 | ||
88 | memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; | |
89 | cur = atomic_long_read(&user->locked_vm); | |
90 | free_uid(user); | |
91 | if (cur + pages > memlock_limit) | |
92 | return -EPERM; | |
93 | return 0; | |
94 | } | |
95 | ||
aaac3ba9 AS |
96 | static int bpf_map_charge_memlock(struct bpf_map *map) |
97 | { | |
98 | struct user_struct *user = get_current_user(); | |
99 | unsigned long memlock_limit; | |
100 | ||
101 | memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; | |
102 | ||
103 | atomic_long_add(map->pages, &user->locked_vm); | |
104 | ||
105 | if (atomic_long_read(&user->locked_vm) > memlock_limit) { | |
106 | atomic_long_sub(map->pages, &user->locked_vm); | |
107 | free_uid(user); | |
108 | return -EPERM; | |
109 | } | |
110 | map->user = user; | |
111 | return 0; | |
112 | } | |
113 | ||
114 | static void bpf_map_uncharge_memlock(struct bpf_map *map) | |
115 | { | |
116 | struct user_struct *user = map->user; | |
117 | ||
118 | atomic_long_sub(map->pages, &user->locked_vm); | |
119 | free_uid(user); | |
120 | } | |
121 | ||
f3f1c054 MKL |
122 | static int bpf_map_alloc_id(struct bpf_map *map) |
123 | { | |
124 | int id; | |
125 | ||
126 | spin_lock_bh(&map_idr_lock); | |
127 | id = idr_alloc_cyclic(&map_idr, map, 1, INT_MAX, GFP_ATOMIC); | |
128 | if (id > 0) | |
129 | map->id = id; | |
130 | spin_unlock_bh(&map_idr_lock); | |
131 | ||
132 | if (WARN_ON_ONCE(!id)) | |
133 | return -ENOSPC; | |
134 | ||
135 | return id > 0 ? 0 : id; | |
136 | } | |
137 | ||
bd5f5f4e | 138 | static void bpf_map_free_id(struct bpf_map *map, bool do_idr_lock) |
f3f1c054 | 139 | { |
bd5f5f4e MKL |
140 | if (do_idr_lock) |
141 | spin_lock_bh(&map_idr_lock); | |
142 | else | |
143 | __acquire(&map_idr_lock); | |
144 | ||
f3f1c054 | 145 | idr_remove(&map_idr, map->id); |
bd5f5f4e MKL |
146 | |
147 | if (do_idr_lock) | |
148 | spin_unlock_bh(&map_idr_lock); | |
149 | else | |
150 | __release(&map_idr_lock); | |
f3f1c054 MKL |
151 | } |
152 | ||
99c55f7d AS |
153 | /* called from workqueue */ |
154 | static void bpf_map_free_deferred(struct work_struct *work) | |
155 | { | |
156 | struct bpf_map *map = container_of(work, struct bpf_map, work); | |
157 | ||
aaac3ba9 | 158 | bpf_map_uncharge_memlock(map); |
99c55f7d AS |
159 | /* implementation dependent freeing */ |
160 | map->ops->map_free(map); | |
161 | } | |
162 | ||
c9da161c DB |
163 | static void bpf_map_put_uref(struct bpf_map *map) |
164 | { | |
165 | if (atomic_dec_and_test(&map->usercnt)) { | |
166 | if (map->map_type == BPF_MAP_TYPE_PROG_ARRAY) | |
167 | bpf_fd_array_map_clear(map); | |
168 | } | |
169 | } | |
170 | ||
99c55f7d AS |
171 | /* decrement map refcnt and schedule it for freeing via workqueue |
172 | * (unrelying map implementation ops->map_free() might sleep) | |
173 | */ | |
bd5f5f4e | 174 | static void __bpf_map_put(struct bpf_map *map, bool do_idr_lock) |
99c55f7d AS |
175 | { |
176 | if (atomic_dec_and_test(&map->refcnt)) { | |
34ad5580 | 177 | /* bpf_map_free_id() must be called first */ |
bd5f5f4e | 178 | bpf_map_free_id(map, do_idr_lock); |
99c55f7d AS |
179 | INIT_WORK(&map->work, bpf_map_free_deferred); |
180 | schedule_work(&map->work); | |
181 | } | |
182 | } | |
183 | ||
bd5f5f4e MKL |
184 | void bpf_map_put(struct bpf_map *map) |
185 | { | |
186 | __bpf_map_put(map, true); | |
187 | } | |
188 | ||
c9da161c | 189 | void bpf_map_put_with_uref(struct bpf_map *map) |
99c55f7d | 190 | { |
c9da161c | 191 | bpf_map_put_uref(map); |
99c55f7d | 192 | bpf_map_put(map); |
c9da161c DB |
193 | } |
194 | ||
195 | static int bpf_map_release(struct inode *inode, struct file *filp) | |
196 | { | |
61d1b6a4 DB |
197 | struct bpf_map *map = filp->private_data; |
198 | ||
199 | if (map->ops->map_release) | |
200 | map->ops->map_release(map, filp); | |
201 | ||
202 | bpf_map_put_with_uref(map); | |
99c55f7d AS |
203 | return 0; |
204 | } | |
205 | ||
f99bf205 DB |
206 | #ifdef CONFIG_PROC_FS |
207 | static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp) | |
208 | { | |
209 | const struct bpf_map *map = filp->private_data; | |
21116b70 DB |
210 | const struct bpf_array *array; |
211 | u32 owner_prog_type = 0; | |
212 | ||
213 | if (map->map_type == BPF_MAP_TYPE_PROG_ARRAY) { | |
214 | array = container_of(map, struct bpf_array, map); | |
215 | owner_prog_type = array->owner_prog_type; | |
216 | } | |
f99bf205 DB |
217 | |
218 | seq_printf(m, | |
219 | "map_type:\t%u\n" | |
220 | "key_size:\t%u\n" | |
221 | "value_size:\t%u\n" | |
322cea2f | 222 | "max_entries:\t%u\n" |
21116b70 DB |
223 | "map_flags:\t%#x\n" |
224 | "memlock:\t%llu\n", | |
f99bf205 DB |
225 | map->map_type, |
226 | map->key_size, | |
227 | map->value_size, | |
322cea2f | 228 | map->max_entries, |
21116b70 DB |
229 | map->map_flags, |
230 | map->pages * 1ULL << PAGE_SHIFT); | |
231 | ||
232 | if (owner_prog_type) | |
233 | seq_printf(m, "owner_prog_type:\t%u\n", | |
234 | owner_prog_type); | |
f99bf205 DB |
235 | } |
236 | #endif | |
237 | ||
99c55f7d | 238 | static const struct file_operations bpf_map_fops = { |
f99bf205 DB |
239 | #ifdef CONFIG_PROC_FS |
240 | .show_fdinfo = bpf_map_show_fdinfo, | |
241 | #endif | |
242 | .release = bpf_map_release, | |
99c55f7d AS |
243 | }; |
244 | ||
b2197755 | 245 | int bpf_map_new_fd(struct bpf_map *map) |
aa79781b DB |
246 | { |
247 | return anon_inode_getfd("bpf-map", &bpf_map_fops, map, | |
248 | O_RDWR | O_CLOEXEC); | |
249 | } | |
250 | ||
99c55f7d AS |
251 | /* helper macro to check that unused fields 'union bpf_attr' are zero */ |
252 | #define CHECK_ATTR(CMD) \ | |
253 | memchr_inv((void *) &attr->CMD##_LAST_FIELD + \ | |
254 | sizeof(attr->CMD##_LAST_FIELD), 0, \ | |
255 | sizeof(*attr) - \ | |
256 | offsetof(union bpf_attr, CMD##_LAST_FIELD) - \ | |
257 | sizeof(attr->CMD##_LAST_FIELD)) != NULL | |
258 | ||
56f668df | 259 | #define BPF_MAP_CREATE_LAST_FIELD inner_map_fd |
99c55f7d AS |
260 | /* called via syscall */ |
261 | static int map_create(union bpf_attr *attr) | |
262 | { | |
263 | struct bpf_map *map; | |
264 | int err; | |
265 | ||
266 | err = CHECK_ATTR(BPF_MAP_CREATE); | |
267 | if (err) | |
268 | return -EINVAL; | |
269 | ||
270 | /* find map type and init map: hashtable vs rbtree vs bloom vs ... */ | |
271 | map = find_and_alloc_map(attr); | |
272 | if (IS_ERR(map)) | |
273 | return PTR_ERR(map); | |
274 | ||
275 | atomic_set(&map->refcnt, 1); | |
c9da161c | 276 | atomic_set(&map->usercnt, 1); |
99c55f7d | 277 | |
aaac3ba9 AS |
278 | err = bpf_map_charge_memlock(map); |
279 | if (err) | |
20b2b24f | 280 | goto free_map_nouncharge; |
aaac3ba9 | 281 | |
f3f1c054 MKL |
282 | err = bpf_map_alloc_id(map); |
283 | if (err) | |
284 | goto free_map; | |
285 | ||
aa79781b | 286 | err = bpf_map_new_fd(map); |
bd5f5f4e MKL |
287 | if (err < 0) { |
288 | /* failed to allocate fd. | |
289 | * bpf_map_put() is needed because the above | |
290 | * bpf_map_alloc_id() has published the map | |
291 | * to the userspace and the userspace may | |
292 | * have refcnt-ed it through BPF_MAP_GET_FD_BY_ID. | |
293 | */ | |
294 | bpf_map_put(map); | |
295 | return err; | |
296 | } | |
99c55f7d | 297 | |
a67edbf4 | 298 | trace_bpf_map_create(map, err); |
99c55f7d AS |
299 | return err; |
300 | ||
301 | free_map: | |
20b2b24f DB |
302 | bpf_map_uncharge_memlock(map); |
303 | free_map_nouncharge: | |
99c55f7d AS |
304 | map->ops->map_free(map); |
305 | return err; | |
306 | } | |
307 | ||
db20fd2b AS |
308 | /* if error is returned, fd is released. |
309 | * On success caller should complete fd access with matching fdput() | |
310 | */ | |
c2101297 | 311 | struct bpf_map *__bpf_map_get(struct fd f) |
db20fd2b | 312 | { |
db20fd2b AS |
313 | if (!f.file) |
314 | return ERR_PTR(-EBADF); | |
db20fd2b AS |
315 | if (f.file->f_op != &bpf_map_fops) { |
316 | fdput(f); | |
317 | return ERR_PTR(-EINVAL); | |
318 | } | |
319 | ||
c2101297 DB |
320 | return f.file->private_data; |
321 | } | |
322 | ||
92117d84 AS |
323 | /* prog's and map's refcnt limit */ |
324 | #define BPF_MAX_REFCNT 32768 | |
325 | ||
326 | struct bpf_map *bpf_map_inc(struct bpf_map *map, bool uref) | |
c9da161c | 327 | { |
92117d84 AS |
328 | if (atomic_inc_return(&map->refcnt) > BPF_MAX_REFCNT) { |
329 | atomic_dec(&map->refcnt); | |
330 | return ERR_PTR(-EBUSY); | |
331 | } | |
c9da161c DB |
332 | if (uref) |
333 | atomic_inc(&map->usercnt); | |
92117d84 | 334 | return map; |
c9da161c DB |
335 | } |
336 | ||
337 | struct bpf_map *bpf_map_get_with_uref(u32 ufd) | |
c2101297 DB |
338 | { |
339 | struct fd f = fdget(ufd); | |
340 | struct bpf_map *map; | |
341 | ||
342 | map = __bpf_map_get(f); | |
343 | if (IS_ERR(map)) | |
344 | return map; | |
345 | ||
92117d84 | 346 | map = bpf_map_inc(map, true); |
c2101297 | 347 | fdput(f); |
db20fd2b AS |
348 | |
349 | return map; | |
350 | } | |
351 | ||
bd5f5f4e MKL |
352 | /* map_idr_lock should have been held */ |
353 | static struct bpf_map *bpf_map_inc_not_zero(struct bpf_map *map, | |
354 | bool uref) | |
355 | { | |
356 | int refold; | |
357 | ||
358 | refold = __atomic_add_unless(&map->refcnt, 1, 0); | |
359 | ||
360 | if (refold >= BPF_MAX_REFCNT) { | |
361 | __bpf_map_put(map, false); | |
362 | return ERR_PTR(-EBUSY); | |
363 | } | |
364 | ||
365 | if (!refold) | |
366 | return ERR_PTR(-ENOENT); | |
367 | ||
368 | if (uref) | |
369 | atomic_inc(&map->usercnt); | |
370 | ||
371 | return map; | |
372 | } | |
373 | ||
b8cdc051 AS |
374 | int __weak bpf_stackmap_copy(struct bpf_map *map, void *key, void *value) |
375 | { | |
376 | return -ENOTSUPP; | |
377 | } | |
378 | ||
db20fd2b AS |
379 | /* last field in 'union bpf_attr' used by this command */ |
380 | #define BPF_MAP_LOOKUP_ELEM_LAST_FIELD value | |
381 | ||
382 | static int map_lookup_elem(union bpf_attr *attr) | |
383 | { | |
535e7b4b MS |
384 | void __user *ukey = u64_to_user_ptr(attr->key); |
385 | void __user *uvalue = u64_to_user_ptr(attr->value); | |
db20fd2b | 386 | int ufd = attr->map_fd; |
db20fd2b | 387 | struct bpf_map *map; |
8ebe667c | 388 | void *key, *value, *ptr; |
15a07b33 | 389 | u32 value_size; |
592867bf | 390 | struct fd f; |
db20fd2b AS |
391 | int err; |
392 | ||
393 | if (CHECK_ATTR(BPF_MAP_LOOKUP_ELEM)) | |
394 | return -EINVAL; | |
395 | ||
592867bf | 396 | f = fdget(ufd); |
c2101297 | 397 | map = __bpf_map_get(f); |
db20fd2b AS |
398 | if (IS_ERR(map)) |
399 | return PTR_ERR(map); | |
400 | ||
401 | err = -ENOMEM; | |
402 | key = kmalloc(map->key_size, GFP_USER); | |
403 | if (!key) | |
404 | goto err_put; | |
405 | ||
406 | err = -EFAULT; | |
407 | if (copy_from_user(key, ukey, map->key_size) != 0) | |
408 | goto free_key; | |
409 | ||
15a07b33 | 410 | if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || |
8f844938 | 411 | map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH || |
15a07b33 AS |
412 | map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) |
413 | value_size = round_up(map->value_size, 8) * num_possible_cpus(); | |
414 | else | |
415 | value_size = map->value_size; | |
416 | ||
8ebe667c | 417 | err = -ENOMEM; |
15a07b33 | 418 | value = kmalloc(value_size, GFP_USER | __GFP_NOWARN); |
db20fd2b | 419 | if (!value) |
8ebe667c AS |
420 | goto free_key; |
421 | ||
8f844938 MKL |
422 | if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || |
423 | map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { | |
15a07b33 AS |
424 | err = bpf_percpu_hash_copy(map, key, value); |
425 | } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) { | |
426 | err = bpf_percpu_array_copy(map, key, value); | |
557c0c6e AS |
427 | } else if (map->map_type == BPF_MAP_TYPE_STACK_TRACE) { |
428 | err = bpf_stackmap_copy(map, key, value); | |
bcc6b1b7 MKL |
429 | } else if (map->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS || |
430 | map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) { | |
56f668df | 431 | err = -ENOTSUPP; |
15a07b33 AS |
432 | } else { |
433 | rcu_read_lock(); | |
434 | ptr = map->ops->map_lookup_elem(map, key); | |
435 | if (ptr) | |
436 | memcpy(value, ptr, value_size); | |
437 | rcu_read_unlock(); | |
438 | err = ptr ? 0 : -ENOENT; | |
439 | } | |
8ebe667c | 440 | |
15a07b33 | 441 | if (err) |
8ebe667c | 442 | goto free_value; |
db20fd2b AS |
443 | |
444 | err = -EFAULT; | |
15a07b33 | 445 | if (copy_to_user(uvalue, value, value_size) != 0) |
8ebe667c | 446 | goto free_value; |
db20fd2b | 447 | |
a67edbf4 | 448 | trace_bpf_map_lookup_elem(map, ufd, key, value); |
db20fd2b AS |
449 | err = 0; |
450 | ||
8ebe667c AS |
451 | free_value: |
452 | kfree(value); | |
db20fd2b AS |
453 | free_key: |
454 | kfree(key); | |
455 | err_put: | |
456 | fdput(f); | |
457 | return err; | |
458 | } | |
459 | ||
3274f520 | 460 | #define BPF_MAP_UPDATE_ELEM_LAST_FIELD flags |
db20fd2b AS |
461 | |
462 | static int map_update_elem(union bpf_attr *attr) | |
463 | { | |
535e7b4b MS |
464 | void __user *ukey = u64_to_user_ptr(attr->key); |
465 | void __user *uvalue = u64_to_user_ptr(attr->value); | |
db20fd2b | 466 | int ufd = attr->map_fd; |
db20fd2b AS |
467 | struct bpf_map *map; |
468 | void *key, *value; | |
15a07b33 | 469 | u32 value_size; |
592867bf | 470 | struct fd f; |
db20fd2b AS |
471 | int err; |
472 | ||
473 | if (CHECK_ATTR(BPF_MAP_UPDATE_ELEM)) | |
474 | return -EINVAL; | |
475 | ||
592867bf | 476 | f = fdget(ufd); |
c2101297 | 477 | map = __bpf_map_get(f); |
db20fd2b AS |
478 | if (IS_ERR(map)) |
479 | return PTR_ERR(map); | |
480 | ||
481 | err = -ENOMEM; | |
482 | key = kmalloc(map->key_size, GFP_USER); | |
483 | if (!key) | |
484 | goto err_put; | |
485 | ||
486 | err = -EFAULT; | |
487 | if (copy_from_user(key, ukey, map->key_size) != 0) | |
488 | goto free_key; | |
489 | ||
15a07b33 | 490 | if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || |
8f844938 | 491 | map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH || |
15a07b33 AS |
492 | map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) |
493 | value_size = round_up(map->value_size, 8) * num_possible_cpus(); | |
494 | else | |
495 | value_size = map->value_size; | |
496 | ||
db20fd2b | 497 | err = -ENOMEM; |
15a07b33 | 498 | value = kmalloc(value_size, GFP_USER | __GFP_NOWARN); |
db20fd2b AS |
499 | if (!value) |
500 | goto free_key; | |
501 | ||
502 | err = -EFAULT; | |
15a07b33 | 503 | if (copy_from_user(value, uvalue, value_size) != 0) |
db20fd2b AS |
504 | goto free_value; |
505 | ||
b121d1e7 AS |
506 | /* must increment bpf_prog_active to avoid kprobe+bpf triggering from |
507 | * inside bpf map update or delete otherwise deadlocks are possible | |
508 | */ | |
509 | preempt_disable(); | |
510 | __this_cpu_inc(bpf_prog_active); | |
8f844938 MKL |
511 | if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH || |
512 | map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) { | |
15a07b33 AS |
513 | err = bpf_percpu_hash_update(map, key, value, attr->flags); |
514 | } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) { | |
515 | err = bpf_percpu_array_update(map, key, value, attr->flags); | |
d056a788 | 516 | } else if (map->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || |
4ed8ec52 | 517 | map->map_type == BPF_MAP_TYPE_PROG_ARRAY || |
56f668df MKL |
518 | map->map_type == BPF_MAP_TYPE_CGROUP_ARRAY || |
519 | map->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS) { | |
d056a788 DB |
520 | rcu_read_lock(); |
521 | err = bpf_fd_array_map_update_elem(map, f.file, key, value, | |
522 | attr->flags); | |
523 | rcu_read_unlock(); | |
bcc6b1b7 MKL |
524 | } else if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) { |
525 | rcu_read_lock(); | |
526 | err = bpf_fd_htab_map_update_elem(map, f.file, key, value, | |
527 | attr->flags); | |
528 | rcu_read_unlock(); | |
15a07b33 AS |
529 | } else { |
530 | rcu_read_lock(); | |
531 | err = map->ops->map_update_elem(map, key, value, attr->flags); | |
532 | rcu_read_unlock(); | |
533 | } | |
b121d1e7 AS |
534 | __this_cpu_dec(bpf_prog_active); |
535 | preempt_enable(); | |
db20fd2b | 536 | |
a67edbf4 DB |
537 | if (!err) |
538 | trace_bpf_map_update_elem(map, ufd, key, value); | |
db20fd2b AS |
539 | free_value: |
540 | kfree(value); | |
541 | free_key: | |
542 | kfree(key); | |
543 | err_put: | |
544 | fdput(f); | |
545 | return err; | |
546 | } | |
547 | ||
548 | #define BPF_MAP_DELETE_ELEM_LAST_FIELD key | |
549 | ||
550 | static int map_delete_elem(union bpf_attr *attr) | |
551 | { | |
535e7b4b | 552 | void __user *ukey = u64_to_user_ptr(attr->key); |
db20fd2b | 553 | int ufd = attr->map_fd; |
db20fd2b | 554 | struct bpf_map *map; |
592867bf | 555 | struct fd f; |
db20fd2b AS |
556 | void *key; |
557 | int err; | |
558 | ||
559 | if (CHECK_ATTR(BPF_MAP_DELETE_ELEM)) | |
560 | return -EINVAL; | |
561 | ||
592867bf | 562 | f = fdget(ufd); |
c2101297 | 563 | map = __bpf_map_get(f); |
db20fd2b AS |
564 | if (IS_ERR(map)) |
565 | return PTR_ERR(map); | |
566 | ||
567 | err = -ENOMEM; | |
568 | key = kmalloc(map->key_size, GFP_USER); | |
569 | if (!key) | |
570 | goto err_put; | |
571 | ||
572 | err = -EFAULT; | |
573 | if (copy_from_user(key, ukey, map->key_size) != 0) | |
574 | goto free_key; | |
575 | ||
b121d1e7 AS |
576 | preempt_disable(); |
577 | __this_cpu_inc(bpf_prog_active); | |
db20fd2b AS |
578 | rcu_read_lock(); |
579 | err = map->ops->map_delete_elem(map, key); | |
580 | rcu_read_unlock(); | |
b121d1e7 AS |
581 | __this_cpu_dec(bpf_prog_active); |
582 | preempt_enable(); | |
db20fd2b | 583 | |
a67edbf4 DB |
584 | if (!err) |
585 | trace_bpf_map_delete_elem(map, ufd, key); | |
db20fd2b AS |
586 | free_key: |
587 | kfree(key); | |
588 | err_put: | |
589 | fdput(f); | |
590 | return err; | |
591 | } | |
592 | ||
593 | /* last field in 'union bpf_attr' used by this command */ | |
594 | #define BPF_MAP_GET_NEXT_KEY_LAST_FIELD next_key | |
595 | ||
596 | static int map_get_next_key(union bpf_attr *attr) | |
597 | { | |
535e7b4b MS |
598 | void __user *ukey = u64_to_user_ptr(attr->key); |
599 | void __user *unext_key = u64_to_user_ptr(attr->next_key); | |
db20fd2b | 600 | int ufd = attr->map_fd; |
db20fd2b AS |
601 | struct bpf_map *map; |
602 | void *key, *next_key; | |
592867bf | 603 | struct fd f; |
db20fd2b AS |
604 | int err; |
605 | ||
606 | if (CHECK_ATTR(BPF_MAP_GET_NEXT_KEY)) | |
607 | return -EINVAL; | |
608 | ||
592867bf | 609 | f = fdget(ufd); |
c2101297 | 610 | map = __bpf_map_get(f); |
db20fd2b AS |
611 | if (IS_ERR(map)) |
612 | return PTR_ERR(map); | |
613 | ||
8fe45924 TQ |
614 | if (ukey) { |
615 | err = -ENOMEM; | |
616 | key = kmalloc(map->key_size, GFP_USER); | |
617 | if (!key) | |
618 | goto err_put; | |
619 | ||
620 | err = -EFAULT; | |
621 | if (copy_from_user(key, ukey, map->key_size) != 0) | |
622 | goto free_key; | |
623 | } else { | |
624 | key = NULL; | |
625 | } | |
db20fd2b AS |
626 | |
627 | err = -ENOMEM; | |
628 | next_key = kmalloc(map->key_size, GFP_USER); | |
629 | if (!next_key) | |
630 | goto free_key; | |
631 | ||
632 | rcu_read_lock(); | |
633 | err = map->ops->map_get_next_key(map, key, next_key); | |
634 | rcu_read_unlock(); | |
635 | if (err) | |
636 | goto free_next_key; | |
637 | ||
638 | err = -EFAULT; | |
639 | if (copy_to_user(unext_key, next_key, map->key_size) != 0) | |
640 | goto free_next_key; | |
641 | ||
a67edbf4 | 642 | trace_bpf_map_next_key(map, ufd, key, next_key); |
db20fd2b AS |
643 | err = 0; |
644 | ||
645 | free_next_key: | |
646 | kfree(next_key); | |
647 | free_key: | |
648 | kfree(key); | |
649 | err_put: | |
650 | fdput(f); | |
651 | return err; | |
652 | } | |
653 | ||
be9370a7 JB |
654 | static const struct bpf_verifier_ops * const bpf_prog_types[] = { |
655 | #define BPF_PROG_TYPE(_id, _ops) \ | |
656 | [_id] = &_ops, | |
40077e0c | 657 | #define BPF_MAP_TYPE(_id, _ops) |
be9370a7 JB |
658 | #include <linux/bpf_types.h> |
659 | #undef BPF_PROG_TYPE | |
40077e0c | 660 | #undef BPF_MAP_TYPE |
be9370a7 | 661 | }; |
09756af4 AS |
662 | |
663 | static int find_prog_type(enum bpf_prog_type type, struct bpf_prog *prog) | |
664 | { | |
be9370a7 JB |
665 | if (type >= ARRAY_SIZE(bpf_prog_types) || !bpf_prog_types[type]) |
666 | return -EINVAL; | |
09756af4 | 667 | |
be9370a7 JB |
668 | prog->aux->ops = bpf_prog_types[type]; |
669 | prog->type = type; | |
670 | return 0; | |
09756af4 AS |
671 | } |
672 | ||
673 | /* drop refcnt on maps used by eBPF program and free auxilary data */ | |
674 | static void free_used_maps(struct bpf_prog_aux *aux) | |
675 | { | |
676 | int i; | |
677 | ||
678 | for (i = 0; i < aux->used_map_cnt; i++) | |
679 | bpf_map_put(aux->used_maps[i]); | |
680 | ||
681 | kfree(aux->used_maps); | |
682 | } | |
683 | ||
5ccb071e DB |
684 | int __bpf_prog_charge(struct user_struct *user, u32 pages) |
685 | { | |
686 | unsigned long memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT; | |
687 | unsigned long user_bufs; | |
688 | ||
689 | if (user) { | |
690 | user_bufs = atomic_long_add_return(pages, &user->locked_vm); | |
691 | if (user_bufs > memlock_limit) { | |
692 | atomic_long_sub(pages, &user->locked_vm); | |
693 | return -EPERM; | |
694 | } | |
695 | } | |
696 | ||
697 | return 0; | |
698 | } | |
699 | ||
700 | void __bpf_prog_uncharge(struct user_struct *user, u32 pages) | |
701 | { | |
702 | if (user) | |
703 | atomic_long_sub(pages, &user->locked_vm); | |
704 | } | |
705 | ||
aaac3ba9 AS |
706 | static int bpf_prog_charge_memlock(struct bpf_prog *prog) |
707 | { | |
708 | struct user_struct *user = get_current_user(); | |
5ccb071e | 709 | int ret; |
aaac3ba9 | 710 | |
5ccb071e DB |
711 | ret = __bpf_prog_charge(user, prog->pages); |
712 | if (ret) { | |
aaac3ba9 | 713 | free_uid(user); |
5ccb071e | 714 | return ret; |
aaac3ba9 | 715 | } |
5ccb071e | 716 | |
aaac3ba9 AS |
717 | prog->aux->user = user; |
718 | return 0; | |
719 | } | |
720 | ||
721 | static void bpf_prog_uncharge_memlock(struct bpf_prog *prog) | |
722 | { | |
723 | struct user_struct *user = prog->aux->user; | |
724 | ||
5ccb071e | 725 | __bpf_prog_uncharge(user, prog->pages); |
aaac3ba9 AS |
726 | free_uid(user); |
727 | } | |
728 | ||
dc4bb0e2 MKL |
729 | static int bpf_prog_alloc_id(struct bpf_prog *prog) |
730 | { | |
731 | int id; | |
732 | ||
733 | spin_lock_bh(&prog_idr_lock); | |
734 | id = idr_alloc_cyclic(&prog_idr, prog, 1, INT_MAX, GFP_ATOMIC); | |
735 | if (id > 0) | |
736 | prog->aux->id = id; | |
737 | spin_unlock_bh(&prog_idr_lock); | |
738 | ||
739 | /* id is in [1, INT_MAX) */ | |
740 | if (WARN_ON_ONCE(!id)) | |
741 | return -ENOSPC; | |
742 | ||
743 | return id > 0 ? 0 : id; | |
744 | } | |
745 | ||
b16d9aa4 | 746 | static void bpf_prog_free_id(struct bpf_prog *prog, bool do_idr_lock) |
dc4bb0e2 MKL |
747 | { |
748 | /* cBPF to eBPF migrations are currently not in the idr store. */ | |
749 | if (!prog->aux->id) | |
750 | return; | |
751 | ||
b16d9aa4 MKL |
752 | if (do_idr_lock) |
753 | spin_lock_bh(&prog_idr_lock); | |
754 | else | |
755 | __acquire(&prog_idr_lock); | |
756 | ||
dc4bb0e2 | 757 | idr_remove(&prog_idr, prog->aux->id); |
b16d9aa4 MKL |
758 | |
759 | if (do_idr_lock) | |
760 | spin_unlock_bh(&prog_idr_lock); | |
761 | else | |
762 | __release(&prog_idr_lock); | |
dc4bb0e2 MKL |
763 | } |
764 | ||
1aacde3d | 765 | static void __bpf_prog_put_rcu(struct rcu_head *rcu) |
abf2e7d6 AS |
766 | { |
767 | struct bpf_prog_aux *aux = container_of(rcu, struct bpf_prog_aux, rcu); | |
768 | ||
769 | free_used_maps(aux); | |
aaac3ba9 | 770 | bpf_prog_uncharge_memlock(aux->prog); |
abf2e7d6 AS |
771 | bpf_prog_free(aux->prog); |
772 | } | |
773 | ||
b16d9aa4 | 774 | static void __bpf_prog_put(struct bpf_prog *prog, bool do_idr_lock) |
09756af4 | 775 | { |
a67edbf4 DB |
776 | if (atomic_dec_and_test(&prog->aux->refcnt)) { |
777 | trace_bpf_prog_put_rcu(prog); | |
34ad5580 | 778 | /* bpf_prog_free_id() must be called first */ |
b16d9aa4 | 779 | bpf_prog_free_id(prog, do_idr_lock); |
74451e66 | 780 | bpf_prog_kallsyms_del(prog); |
1aacde3d | 781 | call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu); |
a67edbf4 | 782 | } |
09756af4 | 783 | } |
b16d9aa4 MKL |
784 | |
785 | void bpf_prog_put(struct bpf_prog *prog) | |
786 | { | |
787 | __bpf_prog_put(prog, true); | |
788 | } | |
e2e9b654 | 789 | EXPORT_SYMBOL_GPL(bpf_prog_put); |
09756af4 AS |
790 | |
791 | static int bpf_prog_release(struct inode *inode, struct file *filp) | |
792 | { | |
793 | struct bpf_prog *prog = filp->private_data; | |
794 | ||
1aacde3d | 795 | bpf_prog_put(prog); |
09756af4 AS |
796 | return 0; |
797 | } | |
798 | ||
7bd509e3 DB |
799 | #ifdef CONFIG_PROC_FS |
800 | static void bpf_prog_show_fdinfo(struct seq_file *m, struct file *filp) | |
801 | { | |
802 | const struct bpf_prog *prog = filp->private_data; | |
f1f7714e | 803 | char prog_tag[sizeof(prog->tag) * 2 + 1] = { }; |
7bd509e3 | 804 | |
f1f7714e | 805 | bin2hex(prog_tag, prog->tag, sizeof(prog->tag)); |
7bd509e3 DB |
806 | seq_printf(m, |
807 | "prog_type:\t%u\n" | |
808 | "prog_jited:\t%u\n" | |
f1f7714e | 809 | "prog_tag:\t%s\n" |
7bd509e3 DB |
810 | "memlock:\t%llu\n", |
811 | prog->type, | |
812 | prog->jited, | |
f1f7714e | 813 | prog_tag, |
7bd509e3 DB |
814 | prog->pages * 1ULL << PAGE_SHIFT); |
815 | } | |
816 | #endif | |
817 | ||
09756af4 | 818 | static const struct file_operations bpf_prog_fops = { |
7bd509e3 DB |
819 | #ifdef CONFIG_PROC_FS |
820 | .show_fdinfo = bpf_prog_show_fdinfo, | |
821 | #endif | |
822 | .release = bpf_prog_release, | |
09756af4 AS |
823 | }; |
824 | ||
b2197755 | 825 | int bpf_prog_new_fd(struct bpf_prog *prog) |
aa79781b DB |
826 | { |
827 | return anon_inode_getfd("bpf-prog", &bpf_prog_fops, prog, | |
828 | O_RDWR | O_CLOEXEC); | |
829 | } | |
830 | ||
113214be | 831 | static struct bpf_prog *____bpf_prog_get(struct fd f) |
09756af4 | 832 | { |
09756af4 AS |
833 | if (!f.file) |
834 | return ERR_PTR(-EBADF); | |
09756af4 AS |
835 | if (f.file->f_op != &bpf_prog_fops) { |
836 | fdput(f); | |
837 | return ERR_PTR(-EINVAL); | |
838 | } | |
839 | ||
c2101297 | 840 | return f.file->private_data; |
09756af4 AS |
841 | } |
842 | ||
59d3656d | 843 | struct bpf_prog *bpf_prog_add(struct bpf_prog *prog, int i) |
92117d84 | 844 | { |
59d3656d BB |
845 | if (atomic_add_return(i, &prog->aux->refcnt) > BPF_MAX_REFCNT) { |
846 | atomic_sub(i, &prog->aux->refcnt); | |
92117d84 AS |
847 | return ERR_PTR(-EBUSY); |
848 | } | |
849 | return prog; | |
850 | } | |
59d3656d BB |
851 | EXPORT_SYMBOL_GPL(bpf_prog_add); |
852 | ||
c540594f DB |
853 | void bpf_prog_sub(struct bpf_prog *prog, int i) |
854 | { | |
855 | /* Only to be used for undoing previous bpf_prog_add() in some | |
856 | * error path. We still know that another entity in our call | |
857 | * path holds a reference to the program, thus atomic_sub() can | |
858 | * be safely used in such cases! | |
859 | */ | |
860 | WARN_ON(atomic_sub_return(i, &prog->aux->refcnt) == 0); | |
861 | } | |
862 | EXPORT_SYMBOL_GPL(bpf_prog_sub); | |
863 | ||
59d3656d BB |
864 | struct bpf_prog *bpf_prog_inc(struct bpf_prog *prog) |
865 | { | |
866 | return bpf_prog_add(prog, 1); | |
867 | } | |
97bc402d | 868 | EXPORT_SYMBOL_GPL(bpf_prog_inc); |
92117d84 | 869 | |
b16d9aa4 MKL |
870 | /* prog_idr_lock should have been held */ |
871 | static struct bpf_prog *bpf_prog_inc_not_zero(struct bpf_prog *prog) | |
872 | { | |
873 | int refold; | |
874 | ||
875 | refold = __atomic_add_unless(&prog->aux->refcnt, 1, 0); | |
876 | ||
877 | if (refold >= BPF_MAX_REFCNT) { | |
878 | __bpf_prog_put(prog, false); | |
879 | return ERR_PTR(-EBUSY); | |
880 | } | |
881 | ||
882 | if (!refold) | |
883 | return ERR_PTR(-ENOENT); | |
884 | ||
885 | return prog; | |
886 | } | |
887 | ||
113214be | 888 | static struct bpf_prog *__bpf_prog_get(u32 ufd, enum bpf_prog_type *type) |
09756af4 AS |
889 | { |
890 | struct fd f = fdget(ufd); | |
891 | struct bpf_prog *prog; | |
892 | ||
113214be | 893 | prog = ____bpf_prog_get(f); |
09756af4 AS |
894 | if (IS_ERR(prog)) |
895 | return prog; | |
113214be DB |
896 | if (type && prog->type != *type) { |
897 | prog = ERR_PTR(-EINVAL); | |
898 | goto out; | |
899 | } | |
09756af4 | 900 | |
92117d84 | 901 | prog = bpf_prog_inc(prog); |
113214be | 902 | out: |
09756af4 AS |
903 | fdput(f); |
904 | return prog; | |
905 | } | |
113214be DB |
906 | |
907 | struct bpf_prog *bpf_prog_get(u32 ufd) | |
908 | { | |
909 | return __bpf_prog_get(ufd, NULL); | |
910 | } | |
911 | ||
912 | struct bpf_prog *bpf_prog_get_type(u32 ufd, enum bpf_prog_type type) | |
913 | { | |
a67edbf4 DB |
914 | struct bpf_prog *prog = __bpf_prog_get(ufd, &type); |
915 | ||
916 | if (!IS_ERR(prog)) | |
917 | trace_bpf_prog_get_type(prog); | |
918 | return prog; | |
113214be DB |
919 | } |
920 | EXPORT_SYMBOL_GPL(bpf_prog_get_type); | |
09756af4 AS |
921 | |
922 | /* last field in 'union bpf_attr' used by this command */ | |
e07b98d9 | 923 | #define BPF_PROG_LOAD_LAST_FIELD prog_flags |
09756af4 AS |
924 | |
925 | static int bpf_prog_load(union bpf_attr *attr) | |
926 | { | |
927 | enum bpf_prog_type type = attr->prog_type; | |
928 | struct bpf_prog *prog; | |
929 | int err; | |
930 | char license[128]; | |
931 | bool is_gpl; | |
932 | ||
933 | if (CHECK_ATTR(BPF_PROG_LOAD)) | |
934 | return -EINVAL; | |
935 | ||
e07b98d9 DM |
936 | if (attr->prog_flags & ~BPF_F_STRICT_ALIGNMENT) |
937 | return -EINVAL; | |
938 | ||
09756af4 | 939 | /* copy eBPF program license from user space */ |
535e7b4b | 940 | if (strncpy_from_user(license, u64_to_user_ptr(attr->license), |
09756af4 AS |
941 | sizeof(license) - 1) < 0) |
942 | return -EFAULT; | |
943 | license[sizeof(license) - 1] = 0; | |
944 | ||
945 | /* eBPF programs must be GPL compatible to use GPL-ed functions */ | |
946 | is_gpl = license_is_gpl_compatible(license); | |
947 | ||
ef0915ca DB |
948 | if (attr->insn_cnt == 0 || attr->insn_cnt > BPF_MAXINSNS) |
949 | return -E2BIG; | |
09756af4 | 950 | |
2541517c AS |
951 | if (type == BPF_PROG_TYPE_KPROBE && |
952 | attr->kern_version != LINUX_VERSION_CODE) | |
953 | return -EINVAL; | |
954 | ||
80b7d819 CF |
955 | if (type != BPF_PROG_TYPE_SOCKET_FILTER && |
956 | type != BPF_PROG_TYPE_CGROUP_SKB && | |
957 | !capable(CAP_SYS_ADMIN)) | |
1be7f75d AS |
958 | return -EPERM; |
959 | ||
09756af4 AS |
960 | /* plain bpf_prog allocation */ |
961 | prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER); | |
962 | if (!prog) | |
963 | return -ENOMEM; | |
964 | ||
aaac3ba9 AS |
965 | err = bpf_prog_charge_memlock(prog); |
966 | if (err) | |
967 | goto free_prog_nouncharge; | |
968 | ||
09756af4 AS |
969 | prog->len = attr->insn_cnt; |
970 | ||
971 | err = -EFAULT; | |
535e7b4b | 972 | if (copy_from_user(prog->insns, u64_to_user_ptr(attr->insns), |
aafe6ae9 | 973 | bpf_prog_insn_size(prog)) != 0) |
09756af4 AS |
974 | goto free_prog; |
975 | ||
976 | prog->orig_prog = NULL; | |
a91263d5 | 977 | prog->jited = 0; |
09756af4 AS |
978 | |
979 | atomic_set(&prog->aux->refcnt, 1); | |
a91263d5 | 980 | prog->gpl_compatible = is_gpl ? 1 : 0; |
09756af4 AS |
981 | |
982 | /* find program type: socket_filter vs tracing_filter */ | |
983 | err = find_prog_type(type, prog); | |
984 | if (err < 0) | |
985 | goto free_prog; | |
986 | ||
987 | /* run eBPF verifier */ | |
9bac3d6d | 988 | err = bpf_check(&prog, attr); |
09756af4 AS |
989 | if (err < 0) |
990 | goto free_used_maps; | |
991 | ||
992 | /* eBPF program is ready to be JITed */ | |
d1c55ab5 | 993 | prog = bpf_prog_select_runtime(prog, &err); |
04fd61ab AS |
994 | if (err < 0) |
995 | goto free_used_maps; | |
09756af4 | 996 | |
dc4bb0e2 MKL |
997 | err = bpf_prog_alloc_id(prog); |
998 | if (err) | |
999 | goto free_used_maps; | |
1000 | ||
aa79781b | 1001 | err = bpf_prog_new_fd(prog); |
b16d9aa4 MKL |
1002 | if (err < 0) { |
1003 | /* failed to allocate fd. | |
1004 | * bpf_prog_put() is needed because the above | |
1005 | * bpf_prog_alloc_id() has published the prog | |
1006 | * to the userspace and the userspace may | |
1007 | * have refcnt-ed it through BPF_PROG_GET_FD_BY_ID. | |
1008 | */ | |
1009 | bpf_prog_put(prog); | |
1010 | return err; | |
1011 | } | |
09756af4 | 1012 | |
74451e66 | 1013 | bpf_prog_kallsyms_add(prog); |
a67edbf4 | 1014 | trace_bpf_prog_load(prog, err); |
09756af4 AS |
1015 | return err; |
1016 | ||
1017 | free_used_maps: | |
1018 | free_used_maps(prog->aux); | |
1019 | free_prog: | |
aaac3ba9 AS |
1020 | bpf_prog_uncharge_memlock(prog); |
1021 | free_prog_nouncharge: | |
09756af4 AS |
1022 | bpf_prog_free(prog); |
1023 | return err; | |
1024 | } | |
1025 | ||
b2197755 DB |
1026 | #define BPF_OBJ_LAST_FIELD bpf_fd |
1027 | ||
1028 | static int bpf_obj_pin(const union bpf_attr *attr) | |
1029 | { | |
1030 | if (CHECK_ATTR(BPF_OBJ)) | |
1031 | return -EINVAL; | |
1032 | ||
535e7b4b | 1033 | return bpf_obj_pin_user(attr->bpf_fd, u64_to_user_ptr(attr->pathname)); |
b2197755 DB |
1034 | } |
1035 | ||
1036 | static int bpf_obj_get(const union bpf_attr *attr) | |
1037 | { | |
1038 | if (CHECK_ATTR(BPF_OBJ) || attr->bpf_fd != 0) | |
1039 | return -EINVAL; | |
1040 | ||
535e7b4b | 1041 | return bpf_obj_get_user(u64_to_user_ptr(attr->pathname)); |
b2197755 DB |
1042 | } |
1043 | ||
f4324551 DM |
1044 | #ifdef CONFIG_CGROUP_BPF |
1045 | ||
7f677633 | 1046 | #define BPF_PROG_ATTACH_LAST_FIELD attach_flags |
f4324551 DM |
1047 | |
1048 | static int bpf_prog_attach(const union bpf_attr *attr) | |
1049 | { | |
7f677633 | 1050 | enum bpf_prog_type ptype; |
f4324551 DM |
1051 | struct bpf_prog *prog; |
1052 | struct cgroup *cgrp; | |
7f677633 | 1053 | int ret; |
f4324551 DM |
1054 | |
1055 | if (!capable(CAP_NET_ADMIN)) | |
1056 | return -EPERM; | |
1057 | ||
1058 | if (CHECK_ATTR(BPF_PROG_ATTACH)) | |
1059 | return -EINVAL; | |
1060 | ||
7f677633 AS |
1061 | if (attr->attach_flags & ~BPF_F_ALLOW_OVERRIDE) |
1062 | return -EINVAL; | |
1063 | ||
f4324551 DM |
1064 | switch (attr->attach_type) { |
1065 | case BPF_CGROUP_INET_INGRESS: | |
1066 | case BPF_CGROUP_INET_EGRESS: | |
b2cd1257 | 1067 | ptype = BPF_PROG_TYPE_CGROUP_SKB; |
f4324551 | 1068 | break; |
61023658 DA |
1069 | case BPF_CGROUP_INET_SOCK_CREATE: |
1070 | ptype = BPF_PROG_TYPE_CGROUP_SOCK; | |
1071 | break; | |
f4324551 DM |
1072 | default: |
1073 | return -EINVAL; | |
1074 | } | |
1075 | ||
b2cd1257 DA |
1076 | prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype); |
1077 | if (IS_ERR(prog)) | |
1078 | return PTR_ERR(prog); | |
1079 | ||
1080 | cgrp = cgroup_get_from_fd(attr->target_fd); | |
1081 | if (IS_ERR(cgrp)) { | |
1082 | bpf_prog_put(prog); | |
1083 | return PTR_ERR(cgrp); | |
1084 | } | |
1085 | ||
7f677633 AS |
1086 | ret = cgroup_bpf_update(cgrp, prog, attr->attach_type, |
1087 | attr->attach_flags & BPF_F_ALLOW_OVERRIDE); | |
1088 | if (ret) | |
1089 | bpf_prog_put(prog); | |
b2cd1257 DA |
1090 | cgroup_put(cgrp); |
1091 | ||
7f677633 | 1092 | return ret; |
f4324551 DM |
1093 | } |
1094 | ||
1095 | #define BPF_PROG_DETACH_LAST_FIELD attach_type | |
1096 | ||
1097 | static int bpf_prog_detach(const union bpf_attr *attr) | |
1098 | { | |
1099 | struct cgroup *cgrp; | |
7f677633 | 1100 | int ret; |
f4324551 DM |
1101 | |
1102 | if (!capable(CAP_NET_ADMIN)) | |
1103 | return -EPERM; | |
1104 | ||
1105 | if (CHECK_ATTR(BPF_PROG_DETACH)) | |
1106 | return -EINVAL; | |
1107 | ||
1108 | switch (attr->attach_type) { | |
1109 | case BPF_CGROUP_INET_INGRESS: | |
1110 | case BPF_CGROUP_INET_EGRESS: | |
61023658 | 1111 | case BPF_CGROUP_INET_SOCK_CREATE: |
f4324551 DM |
1112 | cgrp = cgroup_get_from_fd(attr->target_fd); |
1113 | if (IS_ERR(cgrp)) | |
1114 | return PTR_ERR(cgrp); | |
1115 | ||
7f677633 | 1116 | ret = cgroup_bpf_update(cgrp, NULL, attr->attach_type, false); |
f4324551 DM |
1117 | cgroup_put(cgrp); |
1118 | break; | |
1119 | ||
1120 | default: | |
1121 | return -EINVAL; | |
1122 | } | |
1123 | ||
7f677633 | 1124 | return ret; |
f4324551 DM |
1125 | } |
1126 | #endif /* CONFIG_CGROUP_BPF */ | |
1127 | ||
1cf1cae9 AS |
1128 | #define BPF_PROG_TEST_RUN_LAST_FIELD test.duration |
1129 | ||
1130 | static int bpf_prog_test_run(const union bpf_attr *attr, | |
1131 | union bpf_attr __user *uattr) | |
1132 | { | |
1133 | struct bpf_prog *prog; | |
1134 | int ret = -ENOTSUPP; | |
1135 | ||
1136 | if (CHECK_ATTR(BPF_PROG_TEST_RUN)) | |
1137 | return -EINVAL; | |
1138 | ||
1139 | prog = bpf_prog_get(attr->test.prog_fd); | |
1140 | if (IS_ERR(prog)) | |
1141 | return PTR_ERR(prog); | |
1142 | ||
1143 | if (prog->aux->ops->test_run) | |
1144 | ret = prog->aux->ops->test_run(prog, attr, uattr); | |
1145 | ||
1146 | bpf_prog_put(prog); | |
1147 | return ret; | |
1148 | } | |
1149 | ||
34ad5580 MKL |
1150 | #define BPF_OBJ_GET_NEXT_ID_LAST_FIELD next_id |
1151 | ||
1152 | static int bpf_obj_get_next_id(const union bpf_attr *attr, | |
1153 | union bpf_attr __user *uattr, | |
1154 | struct idr *idr, | |
1155 | spinlock_t *lock) | |
1156 | { | |
1157 | u32 next_id = attr->start_id; | |
1158 | int err = 0; | |
1159 | ||
1160 | if (CHECK_ATTR(BPF_OBJ_GET_NEXT_ID) || next_id >= INT_MAX) | |
1161 | return -EINVAL; | |
1162 | ||
1163 | if (!capable(CAP_SYS_ADMIN)) | |
1164 | return -EPERM; | |
1165 | ||
1166 | next_id++; | |
1167 | spin_lock_bh(lock); | |
1168 | if (!idr_get_next(idr, &next_id)) | |
1169 | err = -ENOENT; | |
1170 | spin_unlock_bh(lock); | |
1171 | ||
1172 | if (!err) | |
1173 | err = put_user(next_id, &uattr->next_id); | |
1174 | ||
1175 | return err; | |
1176 | } | |
1177 | ||
b16d9aa4 MKL |
1178 | #define BPF_PROG_GET_FD_BY_ID_LAST_FIELD prog_id |
1179 | ||
1180 | static int bpf_prog_get_fd_by_id(const union bpf_attr *attr) | |
1181 | { | |
1182 | struct bpf_prog *prog; | |
1183 | u32 id = attr->prog_id; | |
1184 | int fd; | |
1185 | ||
1186 | if (CHECK_ATTR(BPF_PROG_GET_FD_BY_ID)) | |
1187 | return -EINVAL; | |
1188 | ||
1189 | if (!capable(CAP_SYS_ADMIN)) | |
1190 | return -EPERM; | |
1191 | ||
1192 | spin_lock_bh(&prog_idr_lock); | |
1193 | prog = idr_find(&prog_idr, id); | |
1194 | if (prog) | |
1195 | prog = bpf_prog_inc_not_zero(prog); | |
1196 | else | |
1197 | prog = ERR_PTR(-ENOENT); | |
1198 | spin_unlock_bh(&prog_idr_lock); | |
1199 | ||
1200 | if (IS_ERR(prog)) | |
1201 | return PTR_ERR(prog); | |
1202 | ||
1203 | fd = bpf_prog_new_fd(prog); | |
1204 | if (fd < 0) | |
1205 | bpf_prog_put(prog); | |
1206 | ||
1207 | return fd; | |
1208 | } | |
1209 | ||
bd5f5f4e MKL |
1210 | #define BPF_MAP_GET_FD_BY_ID_LAST_FIELD map_id |
1211 | ||
1212 | static int bpf_map_get_fd_by_id(const union bpf_attr *attr) | |
1213 | { | |
1214 | struct bpf_map *map; | |
1215 | u32 id = attr->map_id; | |
1216 | int fd; | |
1217 | ||
1218 | if (CHECK_ATTR(BPF_MAP_GET_FD_BY_ID)) | |
1219 | return -EINVAL; | |
1220 | ||
1221 | if (!capable(CAP_SYS_ADMIN)) | |
1222 | return -EPERM; | |
1223 | ||
1224 | spin_lock_bh(&map_idr_lock); | |
1225 | map = idr_find(&map_idr, id); | |
1226 | if (map) | |
1227 | map = bpf_map_inc_not_zero(map, true); | |
1228 | else | |
1229 | map = ERR_PTR(-ENOENT); | |
1230 | spin_unlock_bh(&map_idr_lock); | |
1231 | ||
1232 | if (IS_ERR(map)) | |
1233 | return PTR_ERR(map); | |
1234 | ||
1235 | fd = bpf_map_new_fd(map); | |
1236 | if (fd < 0) | |
1237 | bpf_map_put(map); | |
1238 | ||
1239 | return fd; | |
1240 | } | |
1241 | ||
99c55f7d AS |
1242 | SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size) |
1243 | { | |
1244 | union bpf_attr attr = {}; | |
1245 | int err; | |
1246 | ||
1be7f75d | 1247 | if (!capable(CAP_SYS_ADMIN) && sysctl_unprivileged_bpf_disabled) |
99c55f7d AS |
1248 | return -EPERM; |
1249 | ||
1250 | if (!access_ok(VERIFY_READ, uattr, 1)) | |
1251 | return -EFAULT; | |
1252 | ||
1253 | if (size > PAGE_SIZE) /* silly large */ | |
1254 | return -E2BIG; | |
1255 | ||
1256 | /* If we're handed a bigger struct than we know of, | |
1257 | * ensure all the unknown bits are 0 - i.e. new | |
1258 | * user-space does not rely on any kernel feature | |
1259 | * extensions we dont know about yet. | |
1260 | */ | |
1261 | if (size > sizeof(attr)) { | |
1262 | unsigned char __user *addr; | |
1263 | unsigned char __user *end; | |
1264 | unsigned char val; | |
1265 | ||
1266 | addr = (void __user *)uattr + sizeof(attr); | |
1267 | end = (void __user *)uattr + size; | |
1268 | ||
1269 | for (; addr < end; addr++) { | |
1270 | err = get_user(val, addr); | |
1271 | if (err) | |
1272 | return err; | |
1273 | if (val) | |
1274 | return -E2BIG; | |
1275 | } | |
1276 | size = sizeof(attr); | |
1277 | } | |
1278 | ||
1279 | /* copy attributes from user space, may be less than sizeof(bpf_attr) */ | |
1280 | if (copy_from_user(&attr, uattr, size) != 0) | |
1281 | return -EFAULT; | |
1282 | ||
1283 | switch (cmd) { | |
1284 | case BPF_MAP_CREATE: | |
1285 | err = map_create(&attr); | |
1286 | break; | |
db20fd2b AS |
1287 | case BPF_MAP_LOOKUP_ELEM: |
1288 | err = map_lookup_elem(&attr); | |
1289 | break; | |
1290 | case BPF_MAP_UPDATE_ELEM: | |
1291 | err = map_update_elem(&attr); | |
1292 | break; | |
1293 | case BPF_MAP_DELETE_ELEM: | |
1294 | err = map_delete_elem(&attr); | |
1295 | break; | |
1296 | case BPF_MAP_GET_NEXT_KEY: | |
1297 | err = map_get_next_key(&attr); | |
1298 | break; | |
09756af4 AS |
1299 | case BPF_PROG_LOAD: |
1300 | err = bpf_prog_load(&attr); | |
1301 | break; | |
b2197755 DB |
1302 | case BPF_OBJ_PIN: |
1303 | err = bpf_obj_pin(&attr); | |
1304 | break; | |
1305 | case BPF_OBJ_GET: | |
1306 | err = bpf_obj_get(&attr); | |
1307 | break; | |
f4324551 DM |
1308 | #ifdef CONFIG_CGROUP_BPF |
1309 | case BPF_PROG_ATTACH: | |
1310 | err = bpf_prog_attach(&attr); | |
1311 | break; | |
1312 | case BPF_PROG_DETACH: | |
1313 | err = bpf_prog_detach(&attr); | |
1314 | break; | |
1315 | #endif | |
1cf1cae9 AS |
1316 | case BPF_PROG_TEST_RUN: |
1317 | err = bpf_prog_test_run(&attr, uattr); | |
1318 | break; | |
34ad5580 MKL |
1319 | case BPF_PROG_GET_NEXT_ID: |
1320 | err = bpf_obj_get_next_id(&attr, uattr, | |
1321 | &prog_idr, &prog_idr_lock); | |
1322 | break; | |
1323 | case BPF_MAP_GET_NEXT_ID: | |
1324 | err = bpf_obj_get_next_id(&attr, uattr, | |
1325 | &map_idr, &map_idr_lock); | |
1326 | break; | |
b16d9aa4 MKL |
1327 | case BPF_PROG_GET_FD_BY_ID: |
1328 | err = bpf_prog_get_fd_by_id(&attr); | |
1329 | break; | |
bd5f5f4e MKL |
1330 | case BPF_MAP_GET_FD_BY_ID: |
1331 | err = bpf_map_get_fd_by_id(&attr); | |
1332 | break; | |
99c55f7d AS |
1333 | default: |
1334 | err = -EINVAL; | |
1335 | break; | |
1336 | } | |
1337 | ||
1338 | return err; | |
1339 | } |