1 // SPDX-License-Identifier: GPL-2.0-only
2 /* Copyright (c) 2011-2014 PLUMgrid, http://plumgrid.com
3 */
4 #include <linux/bpf.h>
5 #include <linux/bpf_trace.h>
6 #include <linux/bpf_lirc.h>
7 #include <linux/btf.h>
8 #include <linux/syscalls.h>
9 #include <linux/slab.h>
10 #include <linux/sched/signal.h>
11 #include <linux/vmalloc.h>
12 #include <linux/mmzone.h>
13 #include <linux/anon_inodes.h>
14 #include <linux/fdtable.h>
15 #include <linux/file.h>
16 #include <linux/fs.h>
17 #include <linux/license.h>
18 #include <linux/filter.h>
19 #include <linux/version.h>
20 #include <linux/kernel.h>
21 #include <linux/idr.h>
22 #include <linux/cred.h>
23 #include <linux/timekeeping.h>
24 #include <linux/ctype.h>
25 #include <linux/nospec.h>
26
27 #define IS_FD_ARRAY(map) ((map)->map_type == BPF_MAP_TYPE_PROG_ARRAY || \
28 (map)->map_type == BPF_MAP_TYPE_PERF_EVENT_ARRAY || \
29 (map)->map_type == BPF_MAP_TYPE_CGROUP_ARRAY || \
30 (map)->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS)
31 #define IS_FD_HASH(map) ((map)->map_type == BPF_MAP_TYPE_HASH_OF_MAPS)
32 #define IS_FD_MAP(map) (IS_FD_ARRAY(map) || IS_FD_HASH(map))
33
34 #define BPF_OBJ_FLAG_MASK (BPF_F_RDONLY | BPF_F_WRONLY)
35
36 DEFINE_PER_CPU(int, bpf_prog_active);
37 static DEFINE_IDR(prog_idr);
38 static DEFINE_SPINLOCK(prog_idr_lock);
39 static DEFINE_IDR(map_idr);
40 static DEFINE_SPINLOCK(map_idr_lock);
41
42 int sysctl_unprivileged_bpf_disabled __read_mostly;
43
44 static const struct bpf_map_ops * const bpf_map_types[] = {
45 #define BPF_PROG_TYPE(_id, _ops)
46 #define BPF_MAP_TYPE(_id, _ops) \
47 [_id] = &_ops,
48 #include <linux/bpf_types.h>
49 #undef BPF_PROG_TYPE
50 #undef BPF_MAP_TYPE
51 };
52
53 /*
54 * If we're handed a bigger struct than we know of, ensure all the unknown bits
55 * are 0 - i.e. new user-space does not rely on any kernel feature extensions
56 * we don't know about yet.
57 *
58 * There is a ToCToU between this function call and the following
59 * copy_from_user() call. However, this is not a concern since this function is
60 * meant to be a future-proofing of bits.
61 */
bpf_check_uarg_tail_zero(void __user * uaddr,size_t expected_size,size_t actual_size)62 int bpf_check_uarg_tail_zero(void __user *uaddr,
63 size_t expected_size,
64 size_t actual_size)
65 {
66 unsigned char __user *addr;
67 unsigned char __user *end;
68 unsigned char val;
69 int err;
70
71 if (unlikely(actual_size > PAGE_SIZE)) /* silly large */
72 return -E2BIG;
73
74 if (unlikely(!access_ok(uaddr, actual_size)))
75 return -EFAULT;
76
77 if (actual_size <= expected_size)
78 return 0;
79
80 addr = uaddr + expected_size;
81 end = uaddr + actual_size;
82
83 for (; addr < end; addr++) {
84 err = get_user(val, addr);
85 if (err)
86 return err;
87 if (val)
88 return -E2BIG;
89 }
90
91 return 0;
92 }
93
94 const struct bpf_map_ops bpf_map_offload_ops = {
95 .map_alloc = bpf_map_offload_map_alloc,
96 .map_free = bpf_map_offload_map_free,
97 .map_check_btf = map_check_no_btf,
98 };
99
find_and_alloc_map(union bpf_attr * attr)100 static struct bpf_map *find_and_alloc_map(union bpf_attr *attr)
101 {
102 const struct bpf_map_ops *ops;
103 u32 type = attr->map_type;
104 struct bpf_map *map;
105 int err;
106
107 if (type >= ARRAY_SIZE(bpf_map_types))
108 return ERR_PTR(-EINVAL);
109 type = array_index_nospec(type, ARRAY_SIZE(bpf_map_types));
110 ops = bpf_map_types[type];
111 if (!ops)
112 return ERR_PTR(-EINVAL);
113
114 if (ops->map_alloc_check) {
115 err = ops->map_alloc_check(attr);
116 if (err)
117 return ERR_PTR(err);
118 }
119 if (attr->map_ifindex)
120 ops = &bpf_map_offload_ops;
121 map = ops->map_alloc(attr);
122 if (IS_ERR(map))
123 return map;
124 map->ops = ops;
125 map->map_type = type;
126 return map;
127 }
128
bpf_map_area_alloc(u64 size,int numa_node)129 void *bpf_map_area_alloc(u64 size, int numa_node)
130 {
131 /* We really just want to fail instead of triggering OOM killer
132 * under memory pressure, therefore we set __GFP_NORETRY to kmalloc,
133 * which is used for lower order allocation requests.
134 *
135 * It has been observed that higher order allocation requests done by
136 * vmalloc with __GFP_NORETRY being set might fail due to not trying
137 * to reclaim memory from the page cache, thus we set
138 * __GFP_RETRY_MAYFAIL to avoid such situations.
139 */
140
141 const gfp_t flags = __GFP_NOWARN | __GFP_ZERO;
142 void *area;
143
144 if (size >= SIZE_MAX)
145 return NULL;
146
147 if (size <= (PAGE_SIZE << PAGE_ALLOC_COSTLY_ORDER)) {
148 area = kmalloc_node(size, GFP_USER | __GFP_NORETRY | flags,
149 numa_node);
150 if (area != NULL)
151 return area;
152 }
153
154 return __vmalloc_node_flags_caller(size, numa_node,
155 GFP_KERNEL | __GFP_RETRY_MAYFAIL |
156 flags, __builtin_return_address(0));
157 }
158
bpf_map_area_free(void * area)159 void bpf_map_area_free(void *area)
160 {
161 kvfree(area);
162 }
163
bpf_map_flags_retain_permanent(u32 flags)164 static u32 bpf_map_flags_retain_permanent(u32 flags)
165 {
166 /* Some map creation flags are not tied to the map object but
167 * rather to the map fd instead, so they have no meaning upon
168 * map object inspection since multiple file descriptors with
169 * different (access) properties can exist here. Thus, given
170 * this has zero meaning for the map itself, lets clear these
171 * from here.
172 */
173 return flags & ~(BPF_F_RDONLY | BPF_F_WRONLY);
174 }
175
bpf_map_init_from_attr(struct bpf_map * map,union bpf_attr * attr)176 void bpf_map_init_from_attr(struct bpf_map *map, union bpf_attr *attr)
177 {
178 map->map_type = attr->map_type;
179 map->key_size = attr->key_size;
180 map->value_size = attr->value_size;
181 map->max_entries = attr->max_entries;
182 map->map_flags = bpf_map_flags_retain_permanent(attr->map_flags);
183 map->numa_node = bpf_map_attr_numa_node(attr);
184 }
185
bpf_charge_memlock(struct user_struct * user,u32 pages)186 static int bpf_charge_memlock(struct user_struct *user, u32 pages)
187 {
188 unsigned long memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
189
190 if (atomic_long_add_return(pages, &user->locked_vm) > memlock_limit) {
191 atomic_long_sub(pages, &user->locked_vm);
192 return -EPERM;
193 }
194 return 0;
195 }
196
bpf_uncharge_memlock(struct user_struct * user,u32 pages)197 static void bpf_uncharge_memlock(struct user_struct *user, u32 pages)
198 {
199 if (user)
200 atomic_long_sub(pages, &user->locked_vm);
201 }
202
bpf_map_charge_init(struct bpf_map_memory * mem,u64 size)203 int bpf_map_charge_init(struct bpf_map_memory *mem, u64 size)
204 {
205 u32 pages = round_up(size, PAGE_SIZE) >> PAGE_SHIFT;
206 struct user_struct *user;
207 int ret;
208
209 if (size >= U32_MAX - PAGE_SIZE)
210 return -E2BIG;
211
212 user = get_current_user();
213 ret = bpf_charge_memlock(user, pages);
214 if (ret) {
215 free_uid(user);
216 return ret;
217 }
218
219 mem->pages = pages;
220 mem->user = user;
221
222 return 0;
223 }
224
bpf_map_charge_finish(struct bpf_map_memory * mem)225 void bpf_map_charge_finish(struct bpf_map_memory *mem)
226 {
227 bpf_uncharge_memlock(mem->user, mem->pages);
228 free_uid(mem->user);
229 }
230
bpf_map_charge_move(struct bpf_map_memory * dst,struct bpf_map_memory * src)231 void bpf_map_charge_move(struct bpf_map_memory *dst,
232 struct bpf_map_memory *src)
233 {
234 *dst = *src;
235
236 /* Make sure src will not be used for the redundant uncharging. */
237 memset(src, 0, sizeof(struct bpf_map_memory));
238 }
239
bpf_map_charge_memlock(struct bpf_map * map,u32 pages)240 int bpf_map_charge_memlock(struct bpf_map *map, u32 pages)
241 {
242 int ret;
243
244 ret = bpf_charge_memlock(map->memory.user, pages);
245 if (ret)
246 return ret;
247 map->memory.pages += pages;
248 return ret;
249 }
250
bpf_map_uncharge_memlock(struct bpf_map * map,u32 pages)251 void bpf_map_uncharge_memlock(struct bpf_map *map, u32 pages)
252 {
253 bpf_uncharge_memlock(map->memory.user, pages);
254 map->memory.pages -= pages;
255 }
256
bpf_map_alloc_id(struct bpf_map * map)257 static int bpf_map_alloc_id(struct bpf_map *map)
258 {
259 int id;
260
261 idr_preload(GFP_KERNEL);
262 spin_lock_bh(&map_idr_lock);
263 id = idr_alloc_cyclic(&map_idr, map, 1, INT_MAX, GFP_ATOMIC);
264 if (id > 0)
265 map->id = id;
266 spin_unlock_bh(&map_idr_lock);
267 idr_preload_end();
268
269 if (WARN_ON_ONCE(!id))
270 return -ENOSPC;
271
272 return id > 0 ? 0 : id;
273 }
274
bpf_map_free_id(struct bpf_map * map,bool do_idr_lock)275 void bpf_map_free_id(struct bpf_map *map, bool do_idr_lock)
276 {
277 unsigned long flags;
278
279 /* Offloaded maps are removed from the IDR store when their device
280 * disappears - even if someone holds an fd to them they are unusable,
281 * the memory is gone, all ops will fail; they are simply waiting for
282 * refcnt to drop to be freed.
283 */
284 if (!map->id)
285 return;
286
287 if (do_idr_lock)
288 spin_lock_irqsave(&map_idr_lock, flags);
289 else
290 __acquire(&map_idr_lock);
291
292 idr_remove(&map_idr, map->id);
293 map->id = 0;
294
295 if (do_idr_lock)
296 spin_unlock_irqrestore(&map_idr_lock, flags);
297 else
298 __release(&map_idr_lock);
299 }
300
301 /* called from workqueue */
bpf_map_free_deferred(struct work_struct * work)302 static void bpf_map_free_deferred(struct work_struct *work)
303 {
304 struct bpf_map *map = container_of(work, struct bpf_map, work);
305 struct bpf_map_memory mem;
306
307 bpf_map_charge_move(&mem, &map->memory);
308 security_bpf_map_free(map);
309 /* implementation dependent freeing */
310 map->ops->map_free(map);
311 bpf_map_charge_finish(&mem);
312 }
313
bpf_map_put_uref(struct bpf_map * map)314 static void bpf_map_put_uref(struct bpf_map *map)
315 {
316 if (atomic_dec_and_test(&map->usercnt)) {
317 if (map->ops->map_release_uref)
318 map->ops->map_release_uref(map);
319 }
320 }
321
322 /* decrement map refcnt and schedule it for freeing via workqueue
323 * (unrelying map implementation ops->map_free() might sleep)
324 */
__bpf_map_put(struct bpf_map * map,bool do_idr_lock)325 static void __bpf_map_put(struct bpf_map *map, bool do_idr_lock)
326 {
327 if (atomic_dec_and_test(&map->refcnt)) {
328 /* bpf_map_free_id() must be called first */
329 bpf_map_free_id(map, do_idr_lock);
330 btf_put(map->btf);
331 INIT_WORK(&map->work, bpf_map_free_deferred);
332 schedule_work(&map->work);
333 }
334 }
335
bpf_map_put(struct bpf_map * map)336 void bpf_map_put(struct bpf_map *map)
337 {
338 __bpf_map_put(map, true);
339 }
340 EXPORT_SYMBOL_GPL(bpf_map_put);
341
bpf_map_put_with_uref(struct bpf_map * map)342 void bpf_map_put_with_uref(struct bpf_map *map)
343 {
344 bpf_map_put_uref(map);
345 bpf_map_put(map);
346 }
347
bpf_map_release(struct inode * inode,struct file * filp)348 static int bpf_map_release(struct inode *inode, struct file *filp)
349 {
350 struct bpf_map *map = filp->private_data;
351
352 if (map->ops->map_release)
353 map->ops->map_release(map, filp);
354
355 bpf_map_put_with_uref(map);
356 return 0;
357 }
358
map_get_sys_perms(struct bpf_map * map,struct fd f)359 static fmode_t map_get_sys_perms(struct bpf_map *map, struct fd f)
360 {
361 fmode_t mode = f.file->f_mode;
362
363 /* Our file permissions may have been overridden by global
364 * map permissions facing syscall side.
365 */
366 if (READ_ONCE(map->frozen))
367 mode &= ~FMODE_CAN_WRITE;
368 return mode;
369 }
370
371 #ifdef CONFIG_PROC_FS
bpf_map_show_fdinfo(struct seq_file * m,struct file * filp)372 static void bpf_map_show_fdinfo(struct seq_file *m, struct file *filp)
373 {
374 const struct bpf_map *map = filp->private_data;
375 const struct bpf_array *array;
376 u32 owner_prog_type = 0;
377 u32 owner_jited = 0;
378
379 if (map->map_type == BPF_MAP_TYPE_PROG_ARRAY) {
380 array = container_of(map, struct bpf_array, map);
381 owner_prog_type = array->owner_prog_type;
382 owner_jited = array->owner_jited;
383 }
384
385 seq_printf(m,
386 "map_type:\t%u\n"
387 "key_size:\t%u\n"
388 "value_size:\t%u\n"
389 "max_entries:\t%u\n"
390 "map_flags:\t%#x\n"
391 "memlock:\t%llu\n"
392 "map_id:\t%u\n"
393 "frozen:\t%u\n",
394 map->map_type,
395 map->key_size,
396 map->value_size,
397 map->max_entries,
398 map->map_flags,
399 map->memory.pages * 1ULL << PAGE_SHIFT,
400 map->id,
401 READ_ONCE(map->frozen));
402
403 if (owner_prog_type) {
404 seq_printf(m, "owner_prog_type:\t%u\n",
405 owner_prog_type);
406 seq_printf(m, "owner_jited:\t%u\n",
407 owner_jited);
408 }
409 }
410 #endif
411
bpf_dummy_read(struct file * filp,char __user * buf,size_t siz,loff_t * ppos)412 static ssize_t bpf_dummy_read(struct file *filp, char __user *buf, size_t siz,
413 loff_t *ppos)
414 {
415 /* We need this handler such that alloc_file() enables
416 * f_mode with FMODE_CAN_READ.
417 */
418 return -EINVAL;
419 }
420
bpf_dummy_write(struct file * filp,const char __user * buf,size_t siz,loff_t * ppos)421 static ssize_t bpf_dummy_write(struct file *filp, const char __user *buf,
422 size_t siz, loff_t *ppos)
423 {
424 /* We need this handler such that alloc_file() enables
425 * f_mode with FMODE_CAN_WRITE.
426 */
427 return -EINVAL;
428 }
429
430 const struct file_operations bpf_map_fops = {
431 #ifdef CONFIG_PROC_FS
432 .show_fdinfo = bpf_map_show_fdinfo,
433 #endif
434 .release = bpf_map_release,
435 .read = bpf_dummy_read,
436 .write = bpf_dummy_write,
437 };
438
bpf_map_new_fd(struct bpf_map * map,int flags)439 int bpf_map_new_fd(struct bpf_map *map, int flags)
440 {
441 int ret;
442
443 ret = security_bpf_map(map, OPEN_FMODE(flags));
444 if (ret < 0)
445 return ret;
446
447 return anon_inode_getfd("bpf-map", &bpf_map_fops, map,
448 flags | O_CLOEXEC);
449 }
450
bpf_get_file_flag(int flags)451 int bpf_get_file_flag(int flags)
452 {
453 if ((flags & BPF_F_RDONLY) && (flags & BPF_F_WRONLY))
454 return -EINVAL;
455 if (flags & BPF_F_RDONLY)
456 return O_RDONLY;
457 if (flags & BPF_F_WRONLY)
458 return O_WRONLY;
459 return O_RDWR;
460 }
461
462 /* helper macro to check that unused fields 'union bpf_attr' are zero */
463 #define CHECK_ATTR(CMD) \
464 memchr_inv((void *) &attr->CMD##_LAST_FIELD + \
465 sizeof(attr->CMD##_LAST_FIELD), 0, \
466 sizeof(*attr) - \
467 offsetof(union bpf_attr, CMD##_LAST_FIELD) - \
468 sizeof(attr->CMD##_LAST_FIELD)) != NULL
469
470 /* dst and src must have at least BPF_OBJ_NAME_LEN number of bytes.
471 * Return 0 on success and < 0 on error.
472 */
bpf_obj_name_cpy(char * dst,const char * src)473 static int bpf_obj_name_cpy(char *dst, const char *src)
474 {
475 const char *end = src + BPF_OBJ_NAME_LEN;
476
477 memset(dst, 0, BPF_OBJ_NAME_LEN);
478 /* Copy all isalnum(), '_' and '.' chars. */
479 while (src < end && *src) {
480 if (!isalnum(*src) &&
481 *src != '_' && *src != '.')
482 return -EINVAL;
483 *dst++ = *src++;
484 }
485
486 /* No '\0' found in BPF_OBJ_NAME_LEN number of bytes */
487 if (src == end)
488 return -EINVAL;
489
490 return 0;
491 }
492
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)493 int map_check_no_btf(const struct bpf_map *map,
494 const struct btf *btf,
495 const struct btf_type *key_type,
496 const struct btf_type *value_type)
497 {
498 return -ENOTSUPP;
499 }
500
map_check_btf(struct bpf_map * map,const struct btf * btf,u32 btf_key_id,u32 btf_value_id)501 static int map_check_btf(struct bpf_map *map, const struct btf *btf,
502 u32 btf_key_id, u32 btf_value_id)
503 {
504 const struct btf_type *key_type, *value_type;
505 u32 key_size, value_size;
506 int ret = 0;
507
508 /* Some maps allow key to be unspecified. */
509 if (btf_key_id) {
510 key_type = btf_type_id_size(btf, &btf_key_id, &key_size);
511 if (!key_type || key_size != map->key_size)
512 return -EINVAL;
513 } else {
514 key_type = btf_type_by_id(btf, 0);
515 if (!map->ops->map_check_btf)
516 return -EINVAL;
517 }
518
519 value_type = btf_type_id_size(btf, &btf_value_id, &value_size);
520 if (!value_type || value_size != map->value_size)
521 return -EINVAL;
522
523 map->spin_lock_off = btf_find_spin_lock(btf, value_type);
524
525 if (map_value_has_spin_lock(map)) {
526 if (map->map_flags & BPF_F_RDONLY_PROG)
527 return -EACCES;
528 if (map->map_type != BPF_MAP_TYPE_HASH &&
529 map->map_type != BPF_MAP_TYPE_ARRAY &&
530 map->map_type != BPF_MAP_TYPE_CGROUP_STORAGE &&
531 map->map_type != BPF_MAP_TYPE_SK_STORAGE)
532 return -ENOTSUPP;
533 if (map->spin_lock_off + sizeof(struct bpf_spin_lock) >
534 map->value_size) {
535 WARN_ONCE(1,
536 "verifier bug spin_lock_off %d value_size %d\n",
537 map->spin_lock_off, map->value_size);
538 return -EFAULT;
539 }
540 }
541
542 if (map->ops->map_check_btf)
543 ret = map->ops->map_check_btf(map, btf, key_type, value_type);
544
545 return ret;
546 }
547
548 #define BPF_MAP_CREATE_LAST_FIELD btf_value_type_id
549 /* called via syscall */
map_create(union bpf_attr * attr)550 static int map_create(union bpf_attr *attr)
551 {
552 int numa_node = bpf_map_attr_numa_node(attr);
553 struct bpf_map_memory mem;
554 struct bpf_map *map;
555 int f_flags;
556 int err;
557
558 err = CHECK_ATTR(BPF_MAP_CREATE);
559 if (err)
560 return -EINVAL;
561
562 f_flags = bpf_get_file_flag(attr->map_flags);
563 if (f_flags < 0)
564 return f_flags;
565
566 if (numa_node != NUMA_NO_NODE &&
567 ((unsigned int)numa_node >= nr_node_ids ||
568 !node_online(numa_node)))
569 return -EINVAL;
570
571 /* find map type and init map: hashtable vs rbtree vs bloom vs ... */
572 map = find_and_alloc_map(attr);
573 if (IS_ERR(map))
574 return PTR_ERR(map);
575
576 err = bpf_obj_name_cpy(map->name, attr->map_name);
577 if (err)
578 goto free_map;
579
580 atomic_set(&map->refcnt, 1);
581 atomic_set(&map->usercnt, 1);
582
583 if (attr->btf_key_type_id || attr->btf_value_type_id) {
584 struct btf *btf;
585
586 if (!attr->btf_value_type_id) {
587 err = -EINVAL;
588 goto free_map;
589 }
590
591 btf = btf_get_by_fd(attr->btf_fd);
592 if (IS_ERR(btf)) {
593 err = PTR_ERR(btf);
594 goto free_map;
595 }
596
597 err = map_check_btf(map, btf, attr->btf_key_type_id,
598 attr->btf_value_type_id);
599 if (err) {
600 btf_put(btf);
601 goto free_map;
602 }
603
604 map->btf = btf;
605 map->btf_key_type_id = attr->btf_key_type_id;
606 map->btf_value_type_id = attr->btf_value_type_id;
607 } else {
608 map->spin_lock_off = -EINVAL;
609 }
610
611 err = security_bpf_map_alloc(map);
612 if (err)
613 goto free_map;
614
615 err = bpf_map_alloc_id(map);
616 if (err)
617 goto free_map_sec;
618
619 err = bpf_map_new_fd(map, f_flags);
620 if (err < 0) {
621 /* failed to allocate fd.
622 * bpf_map_put_with_uref() is needed because the above
623 * bpf_map_alloc_id() has published the map
624 * to the userspace and the userspace may
625 * have refcnt-ed it through BPF_MAP_GET_FD_BY_ID.
626 */
627 bpf_map_put_with_uref(map);
628 return err;
629 }
630
631 return err;
632
633 free_map_sec:
634 security_bpf_map_free(map);
635 free_map:
636 btf_put(map->btf);
637 bpf_map_charge_move(&mem, &map->memory);
638 map->ops->map_free(map);
639 bpf_map_charge_finish(&mem);
640 return err;
641 }
642
643 /* if error is returned, fd is released.
644 * On success caller should complete fd access with matching fdput()
645 */
__bpf_map_get(struct fd f)646 struct bpf_map *__bpf_map_get(struct fd f)
647 {
648 if (!f.file)
649 return ERR_PTR(-EBADF);
650 if (f.file->f_op != &bpf_map_fops) {
651 fdput(f);
652 return ERR_PTR(-EINVAL);
653 }
654
655 return f.file->private_data;
656 }
657
658 /* prog's and map's refcnt limit */
659 #define BPF_MAX_REFCNT 32768
660
bpf_map_inc(struct bpf_map * map,bool uref)661 struct bpf_map *bpf_map_inc(struct bpf_map *map, bool uref)
662 {
663 if (atomic_inc_return(&map->refcnt) > BPF_MAX_REFCNT) {
664 atomic_dec(&map->refcnt);
665 return ERR_PTR(-EBUSY);
666 }
667 if (uref)
668 atomic_inc(&map->usercnt);
669 return map;
670 }
671 EXPORT_SYMBOL_GPL(bpf_map_inc);
672
bpf_map_get_with_uref(u32 ufd)673 struct bpf_map *bpf_map_get_with_uref(u32 ufd)
674 {
675 struct fd f = fdget(ufd);
676 struct bpf_map *map;
677
678 map = __bpf_map_get(f);
679 if (IS_ERR(map))
680 return map;
681
682 map = bpf_map_inc(map, true);
683 fdput(f);
684
685 return map;
686 }
687
688 /* map_idr_lock should have been held */
__bpf_map_inc_not_zero(struct bpf_map * map,bool uref)689 static struct bpf_map *__bpf_map_inc_not_zero(struct bpf_map *map,
690 bool uref)
691 {
692 int refold;
693
694 refold = atomic_fetch_add_unless(&map->refcnt, 1, 0);
695
696 if (refold >= BPF_MAX_REFCNT) {
697 __bpf_map_put(map, false);
698 return ERR_PTR(-EBUSY);
699 }
700
701 if (!refold)
702 return ERR_PTR(-ENOENT);
703
704 if (uref)
705 atomic_inc(&map->usercnt);
706
707 return map;
708 }
709
bpf_map_inc_not_zero(struct bpf_map * map,bool uref)710 struct bpf_map *bpf_map_inc_not_zero(struct bpf_map *map, bool uref)
711 {
712 spin_lock_bh(&map_idr_lock);
713 map = __bpf_map_inc_not_zero(map, uref);
714 spin_unlock_bh(&map_idr_lock);
715
716 return map;
717 }
718 EXPORT_SYMBOL_GPL(bpf_map_inc_not_zero);
719
bpf_stackmap_copy(struct bpf_map * map,void * key,void * value)720 int __weak bpf_stackmap_copy(struct bpf_map *map, void *key, void *value)
721 {
722 return -ENOTSUPP;
723 }
724
__bpf_copy_key(void __user * ukey,u64 key_size)725 static void *__bpf_copy_key(void __user *ukey, u64 key_size)
726 {
727 if (key_size)
728 return memdup_user(ukey, key_size);
729
730 if (ukey)
731 return ERR_PTR(-EINVAL);
732
733 return NULL;
734 }
735
736 /* last field in 'union bpf_attr' used by this command */
737 #define BPF_MAP_LOOKUP_ELEM_LAST_FIELD flags
738
map_lookup_elem(union bpf_attr * attr)739 static int map_lookup_elem(union bpf_attr *attr)
740 {
741 void __user *ukey = u64_to_user_ptr(attr->key);
742 void __user *uvalue = u64_to_user_ptr(attr->value);
743 int ufd = attr->map_fd;
744 struct bpf_map *map;
745 void *key, *value, *ptr;
746 u32 value_size;
747 struct fd f;
748 int err;
749
750 if (CHECK_ATTR(BPF_MAP_LOOKUP_ELEM))
751 return -EINVAL;
752
753 if (attr->flags & ~BPF_F_LOCK)
754 return -EINVAL;
755
756 f = fdget(ufd);
757 map = __bpf_map_get(f);
758 if (IS_ERR(map))
759 return PTR_ERR(map);
760 if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) {
761 err = -EPERM;
762 goto err_put;
763 }
764
765 if ((attr->flags & BPF_F_LOCK) &&
766 !map_value_has_spin_lock(map)) {
767 err = -EINVAL;
768 goto err_put;
769 }
770
771 key = __bpf_copy_key(ukey, map->key_size);
772 if (IS_ERR(key)) {
773 err = PTR_ERR(key);
774 goto err_put;
775 }
776
777 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
778 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH ||
779 map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY ||
780 map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE)
781 value_size = round_up(map->value_size, 8) * num_possible_cpus();
782 else if (IS_FD_MAP(map))
783 value_size = sizeof(u32);
784 else
785 value_size = map->value_size;
786
787 err = -ENOMEM;
788 value = kmalloc(value_size, GFP_USER | __GFP_NOWARN);
789 if (!value)
790 goto free_key;
791
792 if (bpf_map_is_dev_bound(map)) {
793 err = bpf_map_offload_lookup_elem(map, key, value);
794 goto done;
795 }
796
797 preempt_disable();
798 this_cpu_inc(bpf_prog_active);
799 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
800 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
801 err = bpf_percpu_hash_copy(map, key, value);
802 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) {
803 err = bpf_percpu_array_copy(map, key, value);
804 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) {
805 err = bpf_percpu_cgroup_storage_copy(map, key, value);
806 } else if (map->map_type == BPF_MAP_TYPE_STACK_TRACE) {
807 err = bpf_stackmap_copy(map, key, value);
808 } else if (IS_FD_ARRAY(map)) {
809 err = bpf_fd_array_map_lookup_elem(map, key, value);
810 } else if (IS_FD_HASH(map)) {
811 err = bpf_fd_htab_map_lookup_elem(map, key, value);
812 } else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) {
813 err = bpf_fd_reuseport_array_lookup_elem(map, key, value);
814 } else if (map->map_type == BPF_MAP_TYPE_QUEUE ||
815 map->map_type == BPF_MAP_TYPE_STACK) {
816 err = map->ops->map_peek_elem(map, value);
817 } else {
818 rcu_read_lock();
819 if (map->ops->map_lookup_elem_sys_only)
820 ptr = map->ops->map_lookup_elem_sys_only(map, key);
821 else
822 ptr = map->ops->map_lookup_elem(map, key);
823 if (IS_ERR(ptr)) {
824 err = PTR_ERR(ptr);
825 } else if (!ptr) {
826 err = -ENOENT;
827 } else {
828 err = 0;
829 if (attr->flags & BPF_F_LOCK)
830 /* lock 'ptr' and copy everything but lock */
831 copy_map_value_locked(map, value, ptr, true);
832 else
833 copy_map_value(map, value, ptr);
834 /* mask lock, since value wasn't zero inited */
835 check_and_init_map_lock(map, value);
836 }
837 rcu_read_unlock();
838 }
839 this_cpu_dec(bpf_prog_active);
840 preempt_enable();
841
842 done:
843 if (err)
844 goto free_value;
845
846 err = -EFAULT;
847 if (copy_to_user(uvalue, value, value_size) != 0)
848 goto free_value;
849
850 err = 0;
851
852 free_value:
853 kfree(value);
854 free_key:
855 kfree(key);
856 err_put:
857 fdput(f);
858 return err;
859 }
860
maybe_wait_bpf_programs(struct bpf_map * map)861 static void maybe_wait_bpf_programs(struct bpf_map *map)
862 {
863 /* Wait for any running BPF programs to complete so that
864 * userspace, when we return to it, knows that all programs
865 * that could be running use the new map value.
866 */
867 if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS ||
868 map->map_type == BPF_MAP_TYPE_ARRAY_OF_MAPS)
869 synchronize_rcu();
870 }
871
872 #define BPF_MAP_UPDATE_ELEM_LAST_FIELD flags
873
map_update_elem(union bpf_attr * attr)874 static int map_update_elem(union bpf_attr *attr)
875 {
876 void __user *ukey = u64_to_user_ptr(attr->key);
877 void __user *uvalue = u64_to_user_ptr(attr->value);
878 int ufd = attr->map_fd;
879 struct bpf_map *map;
880 void *key, *value;
881 u32 value_size;
882 struct fd f;
883 int err;
884
885 if (CHECK_ATTR(BPF_MAP_UPDATE_ELEM))
886 return -EINVAL;
887
888 f = fdget(ufd);
889 map = __bpf_map_get(f);
890 if (IS_ERR(map))
891 return PTR_ERR(map);
892 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
893 err = -EPERM;
894 goto err_put;
895 }
896
897 if ((attr->flags & BPF_F_LOCK) &&
898 !map_value_has_spin_lock(map)) {
899 err = -EINVAL;
900 goto err_put;
901 }
902
903 key = __bpf_copy_key(ukey, map->key_size);
904 if (IS_ERR(key)) {
905 err = PTR_ERR(key);
906 goto err_put;
907 }
908
909 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
910 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH ||
911 map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY ||
912 map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE)
913 value_size = round_up(map->value_size, 8) * num_possible_cpus();
914 else
915 value_size = map->value_size;
916
917 err = -ENOMEM;
918 value = kmalloc(value_size, GFP_USER | __GFP_NOWARN);
919 if (!value)
920 goto free_key;
921
922 err = -EFAULT;
923 if (copy_from_user(value, uvalue, value_size) != 0)
924 goto free_value;
925
926 /* Need to create a kthread, thus must support schedule */
927 if (bpf_map_is_dev_bound(map)) {
928 err = bpf_map_offload_update_elem(map, key, value, attr->flags);
929 goto out;
930 } else if (map->map_type == BPF_MAP_TYPE_CPUMAP ||
931 map->map_type == BPF_MAP_TYPE_SOCKHASH ||
932 map->map_type == BPF_MAP_TYPE_SOCKMAP) {
933 err = map->ops->map_update_elem(map, key, value, attr->flags);
934 goto out;
935 }
936
937 /* must increment bpf_prog_active to avoid kprobe+bpf triggering from
938 * inside bpf map update or delete otherwise deadlocks are possible
939 */
940 preempt_disable();
941 __this_cpu_inc(bpf_prog_active);
942 if (map->map_type == BPF_MAP_TYPE_PERCPU_HASH ||
943 map->map_type == BPF_MAP_TYPE_LRU_PERCPU_HASH) {
944 err = bpf_percpu_hash_update(map, key, value, attr->flags);
945 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_ARRAY) {
946 err = bpf_percpu_array_update(map, key, value, attr->flags);
947 } else if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE) {
948 err = bpf_percpu_cgroup_storage_update(map, key, value,
949 attr->flags);
950 } else if (IS_FD_ARRAY(map)) {
951 rcu_read_lock();
952 err = bpf_fd_array_map_update_elem(map, f.file, key, value,
953 attr->flags);
954 rcu_read_unlock();
955 } else if (map->map_type == BPF_MAP_TYPE_HASH_OF_MAPS) {
956 rcu_read_lock();
957 err = bpf_fd_htab_map_update_elem(map, f.file, key, value,
958 attr->flags);
959 rcu_read_unlock();
960 } else if (map->map_type == BPF_MAP_TYPE_REUSEPORT_SOCKARRAY) {
961 /* rcu_read_lock() is not needed */
962 err = bpf_fd_reuseport_array_update_elem(map, key, value,
963 attr->flags);
964 } else if (map->map_type == BPF_MAP_TYPE_QUEUE ||
965 map->map_type == BPF_MAP_TYPE_STACK) {
966 err = map->ops->map_push_elem(map, value, attr->flags);
967 } else {
968 rcu_read_lock();
969 err = map->ops->map_update_elem(map, key, value, attr->flags);
970 rcu_read_unlock();
971 }
972 __this_cpu_dec(bpf_prog_active);
973 preempt_enable();
974 maybe_wait_bpf_programs(map);
975 out:
976 free_value:
977 kfree(value);
978 free_key:
979 kfree(key);
980 err_put:
981 fdput(f);
982 return err;
983 }
984
985 #define BPF_MAP_DELETE_ELEM_LAST_FIELD key
986
map_delete_elem(union bpf_attr * attr)987 static int map_delete_elem(union bpf_attr *attr)
988 {
989 void __user *ukey = u64_to_user_ptr(attr->key);
990 int ufd = attr->map_fd;
991 struct bpf_map *map;
992 struct fd f;
993 void *key;
994 int err;
995
996 if (CHECK_ATTR(BPF_MAP_DELETE_ELEM))
997 return -EINVAL;
998
999 f = fdget(ufd);
1000 map = __bpf_map_get(f);
1001 if (IS_ERR(map))
1002 return PTR_ERR(map);
1003 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
1004 err = -EPERM;
1005 goto err_put;
1006 }
1007
1008 key = __bpf_copy_key(ukey, map->key_size);
1009 if (IS_ERR(key)) {
1010 err = PTR_ERR(key);
1011 goto err_put;
1012 }
1013
1014 if (bpf_map_is_dev_bound(map)) {
1015 err = bpf_map_offload_delete_elem(map, key);
1016 goto out;
1017 }
1018
1019 preempt_disable();
1020 __this_cpu_inc(bpf_prog_active);
1021 rcu_read_lock();
1022 err = map->ops->map_delete_elem(map, key);
1023 rcu_read_unlock();
1024 __this_cpu_dec(bpf_prog_active);
1025 preempt_enable();
1026 maybe_wait_bpf_programs(map);
1027 out:
1028 kfree(key);
1029 err_put:
1030 fdput(f);
1031 return err;
1032 }
1033
1034 /* last field in 'union bpf_attr' used by this command */
1035 #define BPF_MAP_GET_NEXT_KEY_LAST_FIELD next_key
1036
map_get_next_key(union bpf_attr * attr)1037 static int map_get_next_key(union bpf_attr *attr)
1038 {
1039 void __user *ukey = u64_to_user_ptr(attr->key);
1040 void __user *unext_key = u64_to_user_ptr(attr->next_key);
1041 int ufd = attr->map_fd;
1042 struct bpf_map *map;
1043 void *key, *next_key;
1044 struct fd f;
1045 int err;
1046
1047 if (CHECK_ATTR(BPF_MAP_GET_NEXT_KEY))
1048 return -EINVAL;
1049
1050 f = fdget(ufd);
1051 map = __bpf_map_get(f);
1052 if (IS_ERR(map))
1053 return PTR_ERR(map);
1054 if (!(map_get_sys_perms(map, f) & FMODE_CAN_READ)) {
1055 err = -EPERM;
1056 goto err_put;
1057 }
1058
1059 if (ukey) {
1060 key = __bpf_copy_key(ukey, map->key_size);
1061 if (IS_ERR(key)) {
1062 err = PTR_ERR(key);
1063 goto err_put;
1064 }
1065 } else {
1066 key = NULL;
1067 }
1068
1069 err = -ENOMEM;
1070 next_key = kmalloc(map->key_size, GFP_USER);
1071 if (!next_key)
1072 goto free_key;
1073
1074 if (bpf_map_is_dev_bound(map)) {
1075 err = bpf_map_offload_get_next_key(map, key, next_key);
1076 goto out;
1077 }
1078
1079 rcu_read_lock();
1080 err = map->ops->map_get_next_key(map, key, next_key);
1081 rcu_read_unlock();
1082 out:
1083 if (err)
1084 goto free_next_key;
1085
1086 err = -EFAULT;
1087 if (copy_to_user(unext_key, next_key, map->key_size) != 0)
1088 goto free_next_key;
1089
1090 err = 0;
1091
1092 free_next_key:
1093 kfree(next_key);
1094 free_key:
1095 kfree(key);
1096 err_put:
1097 fdput(f);
1098 return err;
1099 }
1100
1101 #define BPF_MAP_LOOKUP_AND_DELETE_ELEM_LAST_FIELD value
1102
map_lookup_and_delete_elem(union bpf_attr * attr)1103 static int map_lookup_and_delete_elem(union bpf_attr *attr)
1104 {
1105 void __user *ukey = u64_to_user_ptr(attr->key);
1106 void __user *uvalue = u64_to_user_ptr(attr->value);
1107 int ufd = attr->map_fd;
1108 struct bpf_map *map;
1109 void *key, *value;
1110 u32 value_size;
1111 struct fd f;
1112 int err;
1113
1114 if (CHECK_ATTR(BPF_MAP_LOOKUP_AND_DELETE_ELEM))
1115 return -EINVAL;
1116
1117 f = fdget(ufd);
1118 map = __bpf_map_get(f);
1119 if (IS_ERR(map))
1120 return PTR_ERR(map);
1121 if (!(map_get_sys_perms(map, f) & FMODE_CAN_WRITE)) {
1122 err = -EPERM;
1123 goto err_put;
1124 }
1125
1126 key = __bpf_copy_key(ukey, map->key_size);
1127 if (IS_ERR(key)) {
1128 err = PTR_ERR(key);
1129 goto err_put;
1130 }
1131
1132 value_size = map->value_size;
1133
1134 err = -ENOMEM;
1135 value = kmalloc(value_size, GFP_USER | __GFP_NOWARN);
1136 if (!value)
1137 goto free_key;
1138
1139 if (map->map_type == BPF_MAP_TYPE_QUEUE ||
1140 map->map_type == BPF_MAP_TYPE_STACK) {
1141 err = map->ops->map_pop_elem(map, value);
1142 } else {
1143 err = -ENOTSUPP;
1144 }
1145
1146 if (err)
1147 goto free_value;
1148
1149 if (copy_to_user(uvalue, value, value_size) != 0)
1150 goto free_value;
1151
1152 err = 0;
1153
1154 free_value:
1155 kfree(value);
1156 free_key:
1157 kfree(key);
1158 err_put:
1159 fdput(f);
1160 return err;
1161 }
1162
1163 #define BPF_MAP_FREEZE_LAST_FIELD map_fd
1164
map_freeze(const union bpf_attr * attr)1165 static int map_freeze(const union bpf_attr *attr)
1166 {
1167 int err = 0, ufd = attr->map_fd;
1168 struct bpf_map *map;
1169 struct fd f;
1170
1171 if (CHECK_ATTR(BPF_MAP_FREEZE))
1172 return -EINVAL;
1173
1174 f = fdget(ufd);
1175 map = __bpf_map_get(f);
1176 if (IS_ERR(map))
1177 return PTR_ERR(map);
1178 if (READ_ONCE(map->frozen)) {
1179 err = -EBUSY;
1180 goto err_put;
1181 }
1182 if (!capable(CAP_SYS_ADMIN)) {
1183 err = -EPERM;
1184 goto err_put;
1185 }
1186
1187 WRITE_ONCE(map->frozen, true);
1188 err_put:
1189 fdput(f);
1190 return err;
1191 }
1192
1193 static const struct bpf_prog_ops * const bpf_prog_types[] = {
1194 #define BPF_PROG_TYPE(_id, _name) \
1195 [_id] = & _name ## _prog_ops,
1196 #define BPF_MAP_TYPE(_id, _ops)
1197 #include <linux/bpf_types.h>
1198 #undef BPF_PROG_TYPE
1199 #undef BPF_MAP_TYPE
1200 };
1201
find_prog_type(enum bpf_prog_type type,struct bpf_prog * prog)1202 static int find_prog_type(enum bpf_prog_type type, struct bpf_prog *prog)
1203 {
1204 const struct bpf_prog_ops *ops;
1205
1206 if (type >= ARRAY_SIZE(bpf_prog_types))
1207 return -EINVAL;
1208 type = array_index_nospec(type, ARRAY_SIZE(bpf_prog_types));
1209 ops = bpf_prog_types[type];
1210 if (!ops)
1211 return -EINVAL;
1212
1213 if (!bpf_prog_is_dev_bound(prog->aux))
1214 prog->aux->ops = ops;
1215 else
1216 prog->aux->ops = &bpf_offload_prog_ops;
1217 prog->type = type;
1218 return 0;
1219 }
1220
1221 /* drop refcnt on maps used by eBPF program and free auxilary data */
free_used_maps(struct bpf_prog_aux * aux)1222 static void free_used_maps(struct bpf_prog_aux *aux)
1223 {
1224 enum bpf_cgroup_storage_type stype;
1225 int i;
1226
1227 for_each_cgroup_storage_type(stype) {
1228 if (!aux->cgroup_storage[stype])
1229 continue;
1230 bpf_cgroup_storage_release(aux->prog,
1231 aux->cgroup_storage[stype]);
1232 }
1233
1234 for (i = 0; i < aux->used_map_cnt; i++)
1235 bpf_map_put(aux->used_maps[i]);
1236
1237 kfree(aux->used_maps);
1238 }
1239
__bpf_prog_charge(struct user_struct * user,u32 pages)1240 int __bpf_prog_charge(struct user_struct *user, u32 pages)
1241 {
1242 unsigned long memlock_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
1243 unsigned long user_bufs;
1244
1245 if (user) {
1246 user_bufs = atomic_long_add_return(pages, &user->locked_vm);
1247 if (user_bufs > memlock_limit) {
1248 atomic_long_sub(pages, &user->locked_vm);
1249 return -EPERM;
1250 }
1251 }
1252
1253 return 0;
1254 }
1255
__bpf_prog_uncharge(struct user_struct * user,u32 pages)1256 void __bpf_prog_uncharge(struct user_struct *user, u32 pages)
1257 {
1258 if (user)
1259 atomic_long_sub(pages, &user->locked_vm);
1260 }
1261
bpf_prog_charge_memlock(struct bpf_prog * prog)1262 static int bpf_prog_charge_memlock(struct bpf_prog *prog)
1263 {
1264 struct user_struct *user = get_current_user();
1265 int ret;
1266
1267 ret = __bpf_prog_charge(user, prog->pages);
1268 if (ret) {
1269 free_uid(user);
1270 return ret;
1271 }
1272
1273 prog->aux->user = user;
1274 return 0;
1275 }
1276
bpf_prog_uncharge_memlock(struct bpf_prog * prog)1277 static void bpf_prog_uncharge_memlock(struct bpf_prog *prog)
1278 {
1279 struct user_struct *user = prog->aux->user;
1280
1281 __bpf_prog_uncharge(user, prog->pages);
1282 free_uid(user);
1283 }
1284
bpf_prog_alloc_id(struct bpf_prog * prog)1285 static int bpf_prog_alloc_id(struct bpf_prog *prog)
1286 {
1287 int id;
1288
1289 idr_preload(GFP_KERNEL);
1290 spin_lock_bh(&prog_idr_lock);
1291 id = idr_alloc_cyclic(&prog_idr, prog, 1, INT_MAX, GFP_ATOMIC);
1292 if (id > 0)
1293 prog->aux->id = id;
1294 spin_unlock_bh(&prog_idr_lock);
1295 idr_preload_end();
1296
1297 /* id is in [1, INT_MAX) */
1298 if (WARN_ON_ONCE(!id))
1299 return -ENOSPC;
1300
1301 return id > 0 ? 0 : id;
1302 }
1303
bpf_prog_free_id(struct bpf_prog * prog,bool do_idr_lock)1304 void bpf_prog_free_id(struct bpf_prog *prog, bool do_idr_lock)
1305 {
1306 /* cBPF to eBPF migrations are currently not in the idr store.
1307 * Offloaded programs are removed from the store when their device
1308 * disappears - even if someone grabs an fd to them they are unusable,
1309 * simply waiting for refcnt to drop to be freed.
1310 */
1311 if (!prog->aux->id)
1312 return;
1313
1314 if (do_idr_lock)
1315 spin_lock_bh(&prog_idr_lock);
1316 else
1317 __acquire(&prog_idr_lock);
1318
1319 idr_remove(&prog_idr, prog->aux->id);
1320 prog->aux->id = 0;
1321
1322 if (do_idr_lock)
1323 spin_unlock_bh(&prog_idr_lock);
1324 else
1325 __release(&prog_idr_lock);
1326 }
1327
__bpf_prog_put_rcu(struct rcu_head * rcu)1328 static void __bpf_prog_put_rcu(struct rcu_head *rcu)
1329 {
1330 struct bpf_prog_aux *aux = container_of(rcu, struct bpf_prog_aux, rcu);
1331
1332 kvfree(aux->func_info);
1333 free_used_maps(aux);
1334 bpf_prog_uncharge_memlock(aux->prog);
1335 security_bpf_prog_free(aux);
1336 bpf_prog_free(aux->prog);
1337 }
1338
__bpf_prog_put_noref(struct bpf_prog * prog,bool deferred)1339 static void __bpf_prog_put_noref(struct bpf_prog *prog, bool deferred)
1340 {
1341 bpf_prog_kallsyms_del_all(prog);
1342 btf_put(prog->aux->btf);
1343 bpf_prog_free_linfo(prog);
1344
1345 if (deferred)
1346 call_rcu(&prog->aux->rcu, __bpf_prog_put_rcu);
1347 else
1348 __bpf_prog_put_rcu(&prog->aux->rcu);
1349 }
1350
__bpf_prog_put(struct bpf_prog * prog,bool do_idr_lock)1351 static void __bpf_prog_put(struct bpf_prog *prog, bool do_idr_lock)
1352 {
1353 if (atomic_dec_and_test(&prog->aux->refcnt)) {
1354 perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_UNLOAD, 0);
1355 /* bpf_prog_free_id() must be called first */
1356 bpf_prog_free_id(prog, do_idr_lock);
1357 __bpf_prog_put_noref(prog, true);
1358 }
1359 }
1360
bpf_prog_put(struct bpf_prog * prog)1361 void bpf_prog_put(struct bpf_prog *prog)
1362 {
1363 __bpf_prog_put(prog, true);
1364 }
1365 EXPORT_SYMBOL_GPL(bpf_prog_put);
1366
bpf_prog_release(struct inode * inode,struct file * filp)1367 static int bpf_prog_release(struct inode *inode, struct file *filp)
1368 {
1369 struct bpf_prog *prog = filp->private_data;
1370
1371 bpf_prog_put(prog);
1372 return 0;
1373 }
1374
bpf_prog_get_stats(const struct bpf_prog * prog,struct bpf_prog_stats * stats)1375 static void bpf_prog_get_stats(const struct bpf_prog *prog,
1376 struct bpf_prog_stats *stats)
1377 {
1378 u64 nsecs = 0, cnt = 0;
1379 int cpu;
1380
1381 for_each_possible_cpu(cpu) {
1382 const struct bpf_prog_stats *st;
1383 unsigned int start;
1384 u64 tnsecs, tcnt;
1385
1386 st = per_cpu_ptr(prog->aux->stats, cpu);
1387 do {
1388 start = u64_stats_fetch_begin_irq(&st->syncp);
1389 tnsecs = st->nsecs;
1390 tcnt = st->cnt;
1391 } while (u64_stats_fetch_retry_irq(&st->syncp, start));
1392 nsecs += tnsecs;
1393 cnt += tcnt;
1394 }
1395 stats->nsecs = nsecs;
1396 stats->cnt = cnt;
1397 }
1398
1399 #ifdef CONFIG_PROC_FS
bpf_prog_show_fdinfo(struct seq_file * m,struct file * filp)1400 static void bpf_prog_show_fdinfo(struct seq_file *m, struct file *filp)
1401 {
1402 const struct bpf_prog *prog = filp->private_data;
1403 char prog_tag[sizeof(prog->tag) * 2 + 1] = { };
1404 struct bpf_prog_stats stats;
1405
1406 bpf_prog_get_stats(prog, &stats);
1407 bin2hex(prog_tag, prog->tag, sizeof(prog->tag));
1408 seq_printf(m,
1409 "prog_type:\t%u\n"
1410 "prog_jited:\t%u\n"
1411 "prog_tag:\t%s\n"
1412 "memlock:\t%llu\n"
1413 "prog_id:\t%u\n"
1414 "run_time_ns:\t%llu\n"
1415 "run_cnt:\t%llu\n",
1416 prog->type,
1417 prog->jited,
1418 prog_tag,
1419 prog->pages * 1ULL << PAGE_SHIFT,
1420 prog->aux->id,
1421 stats.nsecs,
1422 stats.cnt);
1423 }
1424 #endif
1425
1426 const struct file_operations bpf_prog_fops = {
1427 #ifdef CONFIG_PROC_FS
1428 .show_fdinfo = bpf_prog_show_fdinfo,
1429 #endif
1430 .release = bpf_prog_release,
1431 .read = bpf_dummy_read,
1432 .write = bpf_dummy_write,
1433 };
1434
bpf_prog_new_fd(struct bpf_prog * prog)1435 int bpf_prog_new_fd(struct bpf_prog *prog)
1436 {
1437 int ret;
1438
1439 ret = security_bpf_prog(prog);
1440 if (ret < 0)
1441 return ret;
1442
1443 return anon_inode_getfd("bpf-prog", &bpf_prog_fops, prog,
1444 O_RDWR | O_CLOEXEC);
1445 }
1446
____bpf_prog_get(struct fd f)1447 static struct bpf_prog *____bpf_prog_get(struct fd f)
1448 {
1449 if (!f.file)
1450 return ERR_PTR(-EBADF);
1451 if (f.file->f_op != &bpf_prog_fops) {
1452 fdput(f);
1453 return ERR_PTR(-EINVAL);
1454 }
1455
1456 return f.file->private_data;
1457 }
1458
bpf_prog_add(struct bpf_prog * prog,int i)1459 struct bpf_prog *bpf_prog_add(struct bpf_prog *prog, int i)
1460 {
1461 if (atomic_add_return(i, &prog->aux->refcnt) > BPF_MAX_REFCNT) {
1462 atomic_sub(i, &prog->aux->refcnt);
1463 return ERR_PTR(-EBUSY);
1464 }
1465 return prog;
1466 }
1467 EXPORT_SYMBOL_GPL(bpf_prog_add);
1468
bpf_prog_sub(struct bpf_prog * prog,int i)1469 void bpf_prog_sub(struct bpf_prog *prog, int i)
1470 {
1471 /* Only to be used for undoing previous bpf_prog_add() in some
1472 * error path. We still know that another entity in our call
1473 * path holds a reference to the program, thus atomic_sub() can
1474 * be safely used in such cases!
1475 */
1476 WARN_ON(atomic_sub_return(i, &prog->aux->refcnt) == 0);
1477 }
1478 EXPORT_SYMBOL_GPL(bpf_prog_sub);
1479
bpf_prog_inc(struct bpf_prog * prog)1480 struct bpf_prog *bpf_prog_inc(struct bpf_prog *prog)
1481 {
1482 return bpf_prog_add(prog, 1);
1483 }
1484 EXPORT_SYMBOL_GPL(bpf_prog_inc);
1485
1486 /* prog_idr_lock should have been held */
bpf_prog_inc_not_zero(struct bpf_prog * prog)1487 struct bpf_prog *bpf_prog_inc_not_zero(struct bpf_prog *prog)
1488 {
1489 int refold;
1490
1491 refold = atomic_fetch_add_unless(&prog->aux->refcnt, 1, 0);
1492
1493 if (refold >= BPF_MAX_REFCNT) {
1494 __bpf_prog_put(prog, false);
1495 return ERR_PTR(-EBUSY);
1496 }
1497
1498 if (!refold)
1499 return ERR_PTR(-ENOENT);
1500
1501 return prog;
1502 }
1503 EXPORT_SYMBOL_GPL(bpf_prog_inc_not_zero);
1504
bpf_prog_get_ok(struct bpf_prog * prog,enum bpf_prog_type * attach_type,bool attach_drv)1505 bool bpf_prog_get_ok(struct bpf_prog *prog,
1506 enum bpf_prog_type *attach_type, bool attach_drv)
1507 {
1508 /* not an attachment, just a refcount inc, always allow */
1509 if (!attach_type)
1510 return true;
1511
1512 if (prog->type != *attach_type)
1513 return false;
1514 if (bpf_prog_is_dev_bound(prog->aux) && !attach_drv)
1515 return false;
1516
1517 return true;
1518 }
1519
__bpf_prog_get(u32 ufd,enum bpf_prog_type * attach_type,bool attach_drv)1520 static struct bpf_prog *__bpf_prog_get(u32 ufd, enum bpf_prog_type *attach_type,
1521 bool attach_drv)
1522 {
1523 struct fd f = fdget(ufd);
1524 struct bpf_prog *prog;
1525
1526 prog = ____bpf_prog_get(f);
1527 if (IS_ERR(prog))
1528 return prog;
1529 if (!bpf_prog_get_ok(prog, attach_type, attach_drv)) {
1530 prog = ERR_PTR(-EINVAL);
1531 goto out;
1532 }
1533
1534 prog = bpf_prog_inc(prog);
1535 out:
1536 fdput(f);
1537 return prog;
1538 }
1539
bpf_prog_get(u32 ufd)1540 struct bpf_prog *bpf_prog_get(u32 ufd)
1541 {
1542 return __bpf_prog_get(ufd, NULL, false);
1543 }
1544
bpf_prog_get_type_dev(u32 ufd,enum bpf_prog_type type,bool attach_drv)1545 struct bpf_prog *bpf_prog_get_type_dev(u32 ufd, enum bpf_prog_type type,
1546 bool attach_drv)
1547 {
1548 return __bpf_prog_get(ufd, &type, attach_drv);
1549 }
1550 EXPORT_SYMBOL_GPL(bpf_prog_get_type_dev);
1551
1552 /* Initially all BPF programs could be loaded w/o specifying
1553 * expected_attach_type. Later for some of them specifying expected_attach_type
1554 * at load time became required so that program could be validated properly.
1555 * Programs of types that are allowed to be loaded both w/ and w/o (for
1556 * backward compatibility) expected_attach_type, should have the default attach
1557 * type assigned to expected_attach_type for the latter case, so that it can be
1558 * validated later at attach time.
1559 *
1560 * bpf_prog_load_fixup_attach_type() sets expected_attach_type in @attr if
1561 * prog type requires it but has some attach types that have to be backward
1562 * compatible.
1563 */
bpf_prog_load_fixup_attach_type(union bpf_attr * attr)1564 static void bpf_prog_load_fixup_attach_type(union bpf_attr *attr)
1565 {
1566 switch (attr->prog_type) {
1567 case BPF_PROG_TYPE_CGROUP_SOCK:
1568 /* Unfortunately BPF_ATTACH_TYPE_UNSPEC enumeration doesn't
1569 * exist so checking for non-zero is the way to go here.
1570 */
1571 if (!attr->expected_attach_type)
1572 attr->expected_attach_type =
1573 BPF_CGROUP_INET_SOCK_CREATE;
1574 break;
1575 }
1576 }
1577
1578 static int
bpf_prog_load_check_attach_type(enum bpf_prog_type prog_type,enum bpf_attach_type expected_attach_type)1579 bpf_prog_load_check_attach_type(enum bpf_prog_type prog_type,
1580 enum bpf_attach_type expected_attach_type)
1581 {
1582 switch (prog_type) {
1583 case BPF_PROG_TYPE_CGROUP_SOCK:
1584 switch (expected_attach_type) {
1585 case BPF_CGROUP_INET_SOCK_CREATE:
1586 case BPF_CGROUP_INET4_POST_BIND:
1587 case BPF_CGROUP_INET6_POST_BIND:
1588 return 0;
1589 default:
1590 return -EINVAL;
1591 }
1592 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
1593 switch (expected_attach_type) {
1594 case BPF_CGROUP_INET4_BIND:
1595 case BPF_CGROUP_INET6_BIND:
1596 case BPF_CGROUP_INET4_CONNECT:
1597 case BPF_CGROUP_INET6_CONNECT:
1598 case BPF_CGROUP_UDP4_SENDMSG:
1599 case BPF_CGROUP_UDP6_SENDMSG:
1600 case BPF_CGROUP_UDP4_RECVMSG:
1601 case BPF_CGROUP_UDP6_RECVMSG:
1602 return 0;
1603 default:
1604 return -EINVAL;
1605 }
1606 case BPF_PROG_TYPE_CGROUP_SKB:
1607 switch (expected_attach_type) {
1608 case BPF_CGROUP_INET_INGRESS:
1609 case BPF_CGROUP_INET_EGRESS:
1610 return 0;
1611 default:
1612 return -EINVAL;
1613 }
1614 case BPF_PROG_TYPE_CGROUP_SOCKOPT:
1615 switch (expected_attach_type) {
1616 case BPF_CGROUP_SETSOCKOPT:
1617 case BPF_CGROUP_GETSOCKOPT:
1618 return 0;
1619 default:
1620 return -EINVAL;
1621 }
1622 default:
1623 return 0;
1624 }
1625 }
1626
1627 /* last field in 'union bpf_attr' used by this command */
1628 #define BPF_PROG_LOAD_LAST_FIELD line_info_cnt
1629
bpf_prog_load(union bpf_attr * attr,union bpf_attr __user * uattr)1630 static int bpf_prog_load(union bpf_attr *attr, union bpf_attr __user *uattr)
1631 {
1632 enum bpf_prog_type type = attr->prog_type;
1633 struct bpf_prog *prog;
1634 int err;
1635 char license[128];
1636 bool is_gpl;
1637
1638 if (CHECK_ATTR(BPF_PROG_LOAD))
1639 return -EINVAL;
1640
1641 if (attr->prog_flags & ~(BPF_F_STRICT_ALIGNMENT |
1642 BPF_F_ANY_ALIGNMENT |
1643 BPF_F_TEST_STATE_FREQ |
1644 BPF_F_TEST_RND_HI32))
1645 return -EINVAL;
1646
1647 if (!IS_ENABLED(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) &&
1648 (attr->prog_flags & BPF_F_ANY_ALIGNMENT) &&
1649 !capable(CAP_SYS_ADMIN))
1650 return -EPERM;
1651
1652 /* copy eBPF program license from user space */
1653 if (strncpy_from_user(license, u64_to_user_ptr(attr->license),
1654 sizeof(license) - 1) < 0)
1655 return -EFAULT;
1656 license[sizeof(license) - 1] = 0;
1657
1658 /* eBPF programs must be GPL compatible to use GPL-ed functions */
1659 is_gpl = license_is_gpl_compatible(license);
1660
1661 if (attr->insn_cnt == 0 ||
1662 attr->insn_cnt > (capable(CAP_SYS_ADMIN) ? BPF_COMPLEXITY_LIMIT_INSNS : BPF_MAXINSNS))
1663 return -E2BIG;
1664 if (type != BPF_PROG_TYPE_SOCKET_FILTER &&
1665 type != BPF_PROG_TYPE_CGROUP_SKB &&
1666 !capable(CAP_SYS_ADMIN))
1667 return -EPERM;
1668
1669 bpf_prog_load_fixup_attach_type(attr);
1670 if (bpf_prog_load_check_attach_type(type, attr->expected_attach_type))
1671 return -EINVAL;
1672
1673 /* plain bpf_prog allocation */
1674 prog = bpf_prog_alloc(bpf_prog_size(attr->insn_cnt), GFP_USER);
1675 if (!prog)
1676 return -ENOMEM;
1677
1678 prog->expected_attach_type = attr->expected_attach_type;
1679
1680 prog->aux->offload_requested = !!attr->prog_ifindex;
1681
1682 err = security_bpf_prog_alloc(prog->aux);
1683 if (err)
1684 goto free_prog_nouncharge;
1685
1686 err = bpf_prog_charge_memlock(prog);
1687 if (err)
1688 goto free_prog_sec;
1689
1690 prog->len = attr->insn_cnt;
1691
1692 err = -EFAULT;
1693 if (copy_from_user(prog->insns, u64_to_user_ptr(attr->insns),
1694 bpf_prog_insn_size(prog)) != 0)
1695 goto free_prog;
1696
1697 prog->orig_prog = NULL;
1698 prog->jited = 0;
1699
1700 atomic_set(&prog->aux->refcnt, 1);
1701 prog->gpl_compatible = is_gpl ? 1 : 0;
1702
1703 if (bpf_prog_is_dev_bound(prog->aux)) {
1704 err = bpf_prog_offload_init(prog, attr);
1705 if (err)
1706 goto free_prog;
1707 }
1708
1709 /* find program type: socket_filter vs tracing_filter */
1710 err = find_prog_type(type, prog);
1711 if (err < 0)
1712 goto free_prog;
1713
1714 prog->aux->load_time = ktime_get_boottime_ns();
1715 err = bpf_obj_name_cpy(prog->aux->name, attr->prog_name);
1716 if (err)
1717 goto free_prog;
1718
1719 /* run eBPF verifier */
1720 err = bpf_check(&prog, attr, uattr);
1721 if (err < 0)
1722 goto free_used_maps;
1723
1724 prog = bpf_prog_select_runtime(prog, &err);
1725 if (err < 0)
1726 goto free_used_maps;
1727
1728 err = bpf_prog_alloc_id(prog);
1729 if (err)
1730 goto free_used_maps;
1731
1732 /* Upon success of bpf_prog_alloc_id(), the BPF prog is
1733 * effectively publicly exposed. However, retrieving via
1734 * bpf_prog_get_fd_by_id() will take another reference,
1735 * therefore it cannot be gone underneath us.
1736 *
1737 * Only for the time /after/ successful bpf_prog_new_fd()
1738 * and before returning to userspace, we might just hold
1739 * one reference and any parallel close on that fd could
1740 * rip everything out. Hence, below notifications must
1741 * happen before bpf_prog_new_fd().
1742 *
1743 * Also, any failure handling from this point onwards must
1744 * be using bpf_prog_put() given the program is exposed.
1745 */
1746 bpf_prog_kallsyms_add(prog);
1747 perf_event_bpf_event(prog, PERF_BPF_EVENT_PROG_LOAD, 0);
1748
1749 err = bpf_prog_new_fd(prog);
1750 if (err < 0)
1751 bpf_prog_put(prog);
1752 return err;
1753
1754 free_used_maps:
1755 /* In case we have subprogs, we need to wait for a grace
1756 * period before we can tear down JIT memory since symbols
1757 * are already exposed under kallsyms.
1758 */
1759 __bpf_prog_put_noref(prog, prog->aux->func_cnt);
1760 return err;
1761 free_prog:
1762 bpf_prog_uncharge_memlock(prog);
1763 free_prog_sec:
1764 security_bpf_prog_free(prog->aux);
1765 free_prog_nouncharge:
1766 bpf_prog_free(prog);
1767 return err;
1768 }
1769
1770 #define BPF_OBJ_LAST_FIELD file_flags
1771
bpf_obj_pin(const union bpf_attr * attr)1772 static int bpf_obj_pin(const union bpf_attr *attr)
1773 {
1774 if (CHECK_ATTR(BPF_OBJ) || attr->file_flags != 0)
1775 return -EINVAL;
1776
1777 return bpf_obj_pin_user(attr->bpf_fd, u64_to_user_ptr(attr->pathname));
1778 }
1779
bpf_obj_get(const union bpf_attr * attr)1780 static int bpf_obj_get(const union bpf_attr *attr)
1781 {
1782 if (CHECK_ATTR(BPF_OBJ) || attr->bpf_fd != 0 ||
1783 attr->file_flags & ~BPF_OBJ_FLAG_MASK)
1784 return -EINVAL;
1785
1786 return bpf_obj_get_user(u64_to_user_ptr(attr->pathname),
1787 attr->file_flags);
1788 }
1789
1790 struct bpf_raw_tracepoint {
1791 struct bpf_raw_event_map *btp;
1792 struct bpf_prog *prog;
1793 };
1794
bpf_raw_tracepoint_release(struct inode * inode,struct file * filp)1795 static int bpf_raw_tracepoint_release(struct inode *inode, struct file *filp)
1796 {
1797 struct bpf_raw_tracepoint *raw_tp = filp->private_data;
1798
1799 if (raw_tp->prog) {
1800 bpf_probe_unregister(raw_tp->btp, raw_tp->prog);
1801 bpf_prog_put(raw_tp->prog);
1802 }
1803 bpf_put_raw_tracepoint(raw_tp->btp);
1804 kfree(raw_tp);
1805 return 0;
1806 }
1807
1808 static const struct file_operations bpf_raw_tp_fops = {
1809 .release = bpf_raw_tracepoint_release,
1810 .read = bpf_dummy_read,
1811 .write = bpf_dummy_write,
1812 };
1813
1814 #define BPF_RAW_TRACEPOINT_OPEN_LAST_FIELD raw_tracepoint.prog_fd
1815
bpf_raw_tracepoint_open(const union bpf_attr * attr)1816 static int bpf_raw_tracepoint_open(const union bpf_attr *attr)
1817 {
1818 struct bpf_raw_tracepoint *raw_tp;
1819 struct bpf_raw_event_map *btp;
1820 struct bpf_prog *prog;
1821 char tp_name[128];
1822 int tp_fd, err;
1823
1824 if (strncpy_from_user(tp_name, u64_to_user_ptr(attr->raw_tracepoint.name),
1825 sizeof(tp_name) - 1) < 0)
1826 return -EFAULT;
1827 tp_name[sizeof(tp_name) - 1] = 0;
1828
1829 btp = bpf_get_raw_tracepoint(tp_name);
1830 if (!btp)
1831 return -ENOENT;
1832
1833 raw_tp = kzalloc(sizeof(*raw_tp), GFP_USER);
1834 if (!raw_tp) {
1835 err = -ENOMEM;
1836 goto out_put_btp;
1837 }
1838 raw_tp->btp = btp;
1839
1840 prog = bpf_prog_get(attr->raw_tracepoint.prog_fd);
1841 if (IS_ERR(prog)) {
1842 err = PTR_ERR(prog);
1843 goto out_free_tp;
1844 }
1845 if (prog->type != BPF_PROG_TYPE_RAW_TRACEPOINT &&
1846 prog->type != BPF_PROG_TYPE_RAW_TRACEPOINT_WRITABLE) {
1847 err = -EINVAL;
1848 goto out_put_prog;
1849 }
1850
1851 err = bpf_probe_register(raw_tp->btp, prog);
1852 if (err)
1853 goto out_put_prog;
1854
1855 raw_tp->prog = prog;
1856 tp_fd = anon_inode_getfd("bpf-raw-tracepoint", &bpf_raw_tp_fops, raw_tp,
1857 O_CLOEXEC);
1858 if (tp_fd < 0) {
1859 bpf_probe_unregister(raw_tp->btp, prog);
1860 err = tp_fd;
1861 goto out_put_prog;
1862 }
1863 return tp_fd;
1864
1865 out_put_prog:
1866 bpf_prog_put(prog);
1867 out_free_tp:
1868 kfree(raw_tp);
1869 out_put_btp:
1870 bpf_put_raw_tracepoint(btp);
1871 return err;
1872 }
1873
bpf_prog_attach_check_attach_type(const struct bpf_prog * prog,enum bpf_attach_type attach_type)1874 static int bpf_prog_attach_check_attach_type(const struct bpf_prog *prog,
1875 enum bpf_attach_type attach_type)
1876 {
1877 switch (prog->type) {
1878 case BPF_PROG_TYPE_CGROUP_SOCK:
1879 case BPF_PROG_TYPE_CGROUP_SOCK_ADDR:
1880 case BPF_PROG_TYPE_CGROUP_SOCKOPT:
1881 return attach_type == prog->expected_attach_type ? 0 : -EINVAL;
1882 case BPF_PROG_TYPE_CGROUP_SKB:
1883 return prog->enforce_expected_attach_type &&
1884 prog->expected_attach_type != attach_type ?
1885 -EINVAL : 0;
1886 default:
1887 return 0;
1888 }
1889 }
1890
1891 #define BPF_PROG_ATTACH_LAST_FIELD attach_flags
1892
1893 #define BPF_F_ATTACH_MASK \
1894 (BPF_F_ALLOW_OVERRIDE | BPF_F_ALLOW_MULTI)
1895
bpf_prog_attach(const union bpf_attr * attr)1896 static int bpf_prog_attach(const union bpf_attr *attr)
1897 {
1898 enum bpf_prog_type ptype;
1899 struct bpf_prog *prog;
1900 int ret;
1901
1902 if (!capable(CAP_NET_ADMIN))
1903 return -EPERM;
1904
1905 if (CHECK_ATTR(BPF_PROG_ATTACH))
1906 return -EINVAL;
1907
1908 if (attr->attach_flags & ~BPF_F_ATTACH_MASK)
1909 return -EINVAL;
1910
1911 switch (attr->attach_type) {
1912 case BPF_CGROUP_INET_INGRESS:
1913 case BPF_CGROUP_INET_EGRESS:
1914 ptype = BPF_PROG_TYPE_CGROUP_SKB;
1915 break;
1916 case BPF_CGROUP_INET_SOCK_CREATE:
1917 case BPF_CGROUP_INET4_POST_BIND:
1918 case BPF_CGROUP_INET6_POST_BIND:
1919 ptype = BPF_PROG_TYPE_CGROUP_SOCK;
1920 break;
1921 case BPF_CGROUP_INET4_BIND:
1922 case BPF_CGROUP_INET6_BIND:
1923 case BPF_CGROUP_INET4_CONNECT:
1924 case BPF_CGROUP_INET6_CONNECT:
1925 case BPF_CGROUP_UDP4_SENDMSG:
1926 case BPF_CGROUP_UDP6_SENDMSG:
1927 case BPF_CGROUP_UDP4_RECVMSG:
1928 case BPF_CGROUP_UDP6_RECVMSG:
1929 ptype = BPF_PROG_TYPE_CGROUP_SOCK_ADDR;
1930 break;
1931 case BPF_CGROUP_SOCK_OPS:
1932 ptype = BPF_PROG_TYPE_SOCK_OPS;
1933 break;
1934 case BPF_CGROUP_DEVICE:
1935 ptype = BPF_PROG_TYPE_CGROUP_DEVICE;
1936 break;
1937 case BPF_SK_MSG_VERDICT:
1938 ptype = BPF_PROG_TYPE_SK_MSG;
1939 break;
1940 case BPF_SK_SKB_STREAM_PARSER:
1941 case BPF_SK_SKB_STREAM_VERDICT:
1942 ptype = BPF_PROG_TYPE_SK_SKB;
1943 break;
1944 case BPF_LIRC_MODE2:
1945 ptype = BPF_PROG_TYPE_LIRC_MODE2;
1946 break;
1947 case BPF_FLOW_DISSECTOR:
1948 ptype = BPF_PROG_TYPE_FLOW_DISSECTOR;
1949 break;
1950 case BPF_CGROUP_SYSCTL:
1951 ptype = BPF_PROG_TYPE_CGROUP_SYSCTL;
1952 break;
1953 case BPF_CGROUP_GETSOCKOPT:
1954 case BPF_CGROUP_SETSOCKOPT:
1955 ptype = BPF_PROG_TYPE_CGROUP_SOCKOPT;
1956 break;
1957 default:
1958 return -EINVAL;
1959 }
1960
1961 prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype);
1962 if (IS_ERR(prog))
1963 return PTR_ERR(prog);
1964
1965 if (bpf_prog_attach_check_attach_type(prog, attr->attach_type)) {
1966 bpf_prog_put(prog);
1967 return -EINVAL;
1968 }
1969
1970 switch (ptype) {
1971 case BPF_PROG_TYPE_SK_SKB:
1972 case BPF_PROG_TYPE_SK_MSG:
1973 ret = sock_map_get_from_fd(attr, prog);
1974 break;
1975 case BPF_PROG_TYPE_LIRC_MODE2:
1976 ret = lirc_prog_attach(attr, prog);
1977 break;
1978 case BPF_PROG_TYPE_FLOW_DISSECTOR:
1979 ret = skb_flow_dissector_bpf_prog_attach(attr, prog);
1980 break;
1981 default:
1982 ret = cgroup_bpf_prog_attach(attr, ptype, prog);
1983 }
1984
1985 if (ret)
1986 bpf_prog_put(prog);
1987 return ret;
1988 }
1989
1990 #define BPF_PROG_DETACH_LAST_FIELD attach_type
1991
bpf_prog_detach(const union bpf_attr * attr)1992 static int bpf_prog_detach(const union bpf_attr *attr)
1993 {
1994 enum bpf_prog_type ptype;
1995
1996 if (!capable(CAP_NET_ADMIN))
1997 return -EPERM;
1998
1999 if (CHECK_ATTR(BPF_PROG_DETACH))
2000 return -EINVAL;
2001
2002 switch (attr->attach_type) {
2003 case BPF_CGROUP_INET_INGRESS:
2004 case BPF_CGROUP_INET_EGRESS:
2005 ptype = BPF_PROG_TYPE_CGROUP_SKB;
2006 break;
2007 case BPF_CGROUP_INET_SOCK_CREATE:
2008 case BPF_CGROUP_INET4_POST_BIND:
2009 case BPF_CGROUP_INET6_POST_BIND:
2010 ptype = BPF_PROG_TYPE_CGROUP_SOCK;
2011 break;
2012 case BPF_CGROUP_INET4_BIND:
2013 case BPF_CGROUP_INET6_BIND:
2014 case BPF_CGROUP_INET4_CONNECT:
2015 case BPF_CGROUP_INET6_CONNECT:
2016 case BPF_CGROUP_UDP4_SENDMSG:
2017 case BPF_CGROUP_UDP6_SENDMSG:
2018 case BPF_CGROUP_UDP4_RECVMSG:
2019 case BPF_CGROUP_UDP6_RECVMSG:
2020 ptype = BPF_PROG_TYPE_CGROUP_SOCK_ADDR;
2021 break;
2022 case BPF_CGROUP_SOCK_OPS:
2023 ptype = BPF_PROG_TYPE_SOCK_OPS;
2024 break;
2025 case BPF_CGROUP_DEVICE:
2026 ptype = BPF_PROG_TYPE_CGROUP_DEVICE;
2027 break;
2028 case BPF_SK_MSG_VERDICT:
2029 return sock_map_get_from_fd(attr, NULL);
2030 case BPF_SK_SKB_STREAM_PARSER:
2031 case BPF_SK_SKB_STREAM_VERDICT:
2032 return sock_map_get_from_fd(attr, NULL);
2033 case BPF_LIRC_MODE2:
2034 return lirc_prog_detach(attr);
2035 case BPF_FLOW_DISSECTOR:
2036 return skb_flow_dissector_bpf_prog_detach(attr);
2037 case BPF_CGROUP_SYSCTL:
2038 ptype = BPF_PROG_TYPE_CGROUP_SYSCTL;
2039 break;
2040 case BPF_CGROUP_GETSOCKOPT:
2041 case BPF_CGROUP_SETSOCKOPT:
2042 ptype = BPF_PROG_TYPE_CGROUP_SOCKOPT;
2043 break;
2044 default:
2045 return -EINVAL;
2046 }
2047
2048 return cgroup_bpf_prog_detach(attr, ptype);
2049 }
2050
2051 #define BPF_PROG_QUERY_LAST_FIELD query.prog_cnt
2052
bpf_prog_query(const union bpf_attr * attr,union bpf_attr __user * uattr)2053 static int bpf_prog_query(const union bpf_attr *attr,
2054 union bpf_attr __user *uattr)
2055 {
2056 if (!capable(CAP_NET_ADMIN))
2057 return -EPERM;
2058 if (CHECK_ATTR(BPF_PROG_QUERY))
2059 return -EINVAL;
2060 if (attr->query.query_flags & ~BPF_F_QUERY_EFFECTIVE)
2061 return -EINVAL;
2062
2063 switch (attr->query.attach_type) {
2064 case BPF_CGROUP_INET_INGRESS:
2065 case BPF_CGROUP_INET_EGRESS:
2066 case BPF_CGROUP_INET_SOCK_CREATE:
2067 case BPF_CGROUP_INET4_BIND:
2068 case BPF_CGROUP_INET6_BIND:
2069 case BPF_CGROUP_INET4_POST_BIND:
2070 case BPF_CGROUP_INET6_POST_BIND:
2071 case BPF_CGROUP_INET4_CONNECT:
2072 case BPF_CGROUP_INET6_CONNECT:
2073 case BPF_CGROUP_UDP4_SENDMSG:
2074 case BPF_CGROUP_UDP6_SENDMSG:
2075 case BPF_CGROUP_UDP4_RECVMSG:
2076 case BPF_CGROUP_UDP6_RECVMSG:
2077 case BPF_CGROUP_SOCK_OPS:
2078 case BPF_CGROUP_DEVICE:
2079 case BPF_CGROUP_SYSCTL:
2080 case BPF_CGROUP_GETSOCKOPT:
2081 case BPF_CGROUP_SETSOCKOPT:
2082 break;
2083 case BPF_LIRC_MODE2:
2084 return lirc_prog_query(attr, uattr);
2085 case BPF_FLOW_DISSECTOR:
2086 return skb_flow_dissector_prog_query(attr, uattr);
2087 default:
2088 return -EINVAL;
2089 }
2090
2091 return cgroup_bpf_prog_query(attr, uattr);
2092 }
2093
2094 #define BPF_PROG_TEST_RUN_LAST_FIELD test.ctx_out
2095
bpf_prog_test_run(const union bpf_attr * attr,union bpf_attr __user * uattr)2096 static int bpf_prog_test_run(const union bpf_attr *attr,
2097 union bpf_attr __user *uattr)
2098 {
2099 struct bpf_prog *prog;
2100 int ret = -ENOTSUPP;
2101
2102 if (!capable(CAP_SYS_ADMIN))
2103 return -EPERM;
2104 if (CHECK_ATTR(BPF_PROG_TEST_RUN))
2105 return -EINVAL;
2106
2107 if ((attr->test.ctx_size_in && !attr->test.ctx_in) ||
2108 (!attr->test.ctx_size_in && attr->test.ctx_in))
2109 return -EINVAL;
2110
2111 if ((attr->test.ctx_size_out && !attr->test.ctx_out) ||
2112 (!attr->test.ctx_size_out && attr->test.ctx_out))
2113 return -EINVAL;
2114
2115 prog = bpf_prog_get(attr->test.prog_fd);
2116 if (IS_ERR(prog))
2117 return PTR_ERR(prog);
2118
2119 if (prog->aux->ops->test_run)
2120 ret = prog->aux->ops->test_run(prog, attr, uattr);
2121
2122 bpf_prog_put(prog);
2123 return ret;
2124 }
2125
2126 #define BPF_OBJ_GET_NEXT_ID_LAST_FIELD next_id
2127
bpf_obj_get_next_id(const union bpf_attr * attr,union bpf_attr __user * uattr,struct idr * idr,spinlock_t * lock)2128 static int bpf_obj_get_next_id(const union bpf_attr *attr,
2129 union bpf_attr __user *uattr,
2130 struct idr *idr,
2131 spinlock_t *lock)
2132 {
2133 u32 next_id = attr->start_id;
2134 int err = 0;
2135
2136 if (CHECK_ATTR(BPF_OBJ_GET_NEXT_ID) || next_id >= INT_MAX)
2137 return -EINVAL;
2138
2139 if (!capable(CAP_SYS_ADMIN))
2140 return -EPERM;
2141
2142 next_id++;
2143 spin_lock_bh(lock);
2144 if (!idr_get_next(idr, &next_id))
2145 err = -ENOENT;
2146 spin_unlock_bh(lock);
2147
2148 if (!err)
2149 err = put_user(next_id, &uattr->next_id);
2150
2151 return err;
2152 }
2153
2154 #define BPF_PROG_GET_FD_BY_ID_LAST_FIELD prog_id
2155
bpf_prog_get_fd_by_id(const union bpf_attr * attr)2156 static int bpf_prog_get_fd_by_id(const union bpf_attr *attr)
2157 {
2158 struct bpf_prog *prog;
2159 u32 id = attr->prog_id;
2160 int fd;
2161
2162 if (CHECK_ATTR(BPF_PROG_GET_FD_BY_ID))
2163 return -EINVAL;
2164
2165 if (!capable(CAP_SYS_ADMIN))
2166 return -EPERM;
2167
2168 spin_lock_bh(&prog_idr_lock);
2169 prog = idr_find(&prog_idr, id);
2170 if (prog)
2171 prog = bpf_prog_inc_not_zero(prog);
2172 else
2173 prog = ERR_PTR(-ENOENT);
2174 spin_unlock_bh(&prog_idr_lock);
2175
2176 if (IS_ERR(prog))
2177 return PTR_ERR(prog);
2178
2179 fd = bpf_prog_new_fd(prog);
2180 if (fd < 0)
2181 bpf_prog_put(prog);
2182
2183 return fd;
2184 }
2185
2186 #define BPF_MAP_GET_FD_BY_ID_LAST_FIELD open_flags
2187
bpf_map_get_fd_by_id(const union bpf_attr * attr)2188 static int bpf_map_get_fd_by_id(const union bpf_attr *attr)
2189 {
2190 struct bpf_map *map;
2191 u32 id = attr->map_id;
2192 int f_flags;
2193 int fd;
2194
2195 if (CHECK_ATTR(BPF_MAP_GET_FD_BY_ID) ||
2196 attr->open_flags & ~BPF_OBJ_FLAG_MASK)
2197 return -EINVAL;
2198
2199 if (!capable(CAP_SYS_ADMIN))
2200 return -EPERM;
2201
2202 f_flags = bpf_get_file_flag(attr->open_flags);
2203 if (f_flags < 0)
2204 return f_flags;
2205
2206 spin_lock_bh(&map_idr_lock);
2207 map = idr_find(&map_idr, id);
2208 if (map)
2209 map = __bpf_map_inc_not_zero(map, true);
2210 else
2211 map = ERR_PTR(-ENOENT);
2212 spin_unlock_bh(&map_idr_lock);
2213
2214 if (IS_ERR(map))
2215 return PTR_ERR(map);
2216
2217 fd = bpf_map_new_fd(map, f_flags);
2218 if (fd < 0)
2219 bpf_map_put_with_uref(map);
2220
2221 return fd;
2222 }
2223
bpf_map_from_imm(const struct bpf_prog * prog,unsigned long addr,u32 * off,u32 * type)2224 static const struct bpf_map *bpf_map_from_imm(const struct bpf_prog *prog,
2225 unsigned long addr, u32 *off,
2226 u32 *type)
2227 {
2228 const struct bpf_map *map;
2229 int i;
2230
2231 for (i = 0, *off = 0; i < prog->aux->used_map_cnt; i++) {
2232 map = prog->aux->used_maps[i];
2233 if (map == (void *)addr) {
2234 *type = BPF_PSEUDO_MAP_FD;
2235 return map;
2236 }
2237 if (!map->ops->map_direct_value_meta)
2238 continue;
2239 if (!map->ops->map_direct_value_meta(map, addr, off)) {
2240 *type = BPF_PSEUDO_MAP_VALUE;
2241 return map;
2242 }
2243 }
2244
2245 return NULL;
2246 }
2247
bpf_insn_prepare_dump(const struct bpf_prog * prog)2248 static struct bpf_insn *bpf_insn_prepare_dump(const struct bpf_prog *prog)
2249 {
2250 const struct bpf_map *map;
2251 struct bpf_insn *insns;
2252 u32 off, type;
2253 u64 imm;
2254 int i;
2255
2256 insns = kmemdup(prog->insnsi, bpf_prog_insn_size(prog),
2257 GFP_USER);
2258 if (!insns)
2259 return insns;
2260
2261 for (i = 0; i < prog->len; i++) {
2262 if (insns[i].code == (BPF_JMP | BPF_TAIL_CALL)) {
2263 insns[i].code = BPF_JMP | BPF_CALL;
2264 insns[i].imm = BPF_FUNC_tail_call;
2265 /* fall-through */
2266 }
2267 if (insns[i].code == (BPF_JMP | BPF_CALL) ||
2268 insns[i].code == (BPF_JMP | BPF_CALL_ARGS)) {
2269 if (insns[i].code == (BPF_JMP | BPF_CALL_ARGS))
2270 insns[i].code = BPF_JMP | BPF_CALL;
2271 if (!bpf_dump_raw_ok())
2272 insns[i].imm = 0;
2273 continue;
2274 }
2275
2276 if (insns[i].code != (BPF_LD | BPF_IMM | BPF_DW))
2277 continue;
2278
2279 imm = ((u64)insns[i + 1].imm << 32) | (u32)insns[i].imm;
2280 map = bpf_map_from_imm(prog, imm, &off, &type);
2281 if (map) {
2282 insns[i].src_reg = type;
2283 insns[i].imm = map->id;
2284 insns[i + 1].imm = off;
2285 continue;
2286 }
2287 }
2288
2289 return insns;
2290 }
2291
set_info_rec_size(struct bpf_prog_info * info)2292 static int set_info_rec_size(struct bpf_prog_info *info)
2293 {
2294 /*
2295 * Ensure info.*_rec_size is the same as kernel expected size
2296 *
2297 * or
2298 *
2299 * Only allow zero *_rec_size if both _rec_size and _cnt are
2300 * zero. In this case, the kernel will set the expected
2301 * _rec_size back to the info.
2302 */
2303
2304 if ((info->nr_func_info || info->func_info_rec_size) &&
2305 info->func_info_rec_size != sizeof(struct bpf_func_info))
2306 return -EINVAL;
2307
2308 if ((info->nr_line_info || info->line_info_rec_size) &&
2309 info->line_info_rec_size != sizeof(struct bpf_line_info))
2310 return -EINVAL;
2311
2312 if ((info->nr_jited_line_info || info->jited_line_info_rec_size) &&
2313 info->jited_line_info_rec_size != sizeof(__u64))
2314 return -EINVAL;
2315
2316 info->func_info_rec_size = sizeof(struct bpf_func_info);
2317 info->line_info_rec_size = sizeof(struct bpf_line_info);
2318 info->jited_line_info_rec_size = sizeof(__u64);
2319
2320 return 0;
2321 }
2322
bpf_prog_get_info_by_fd(struct bpf_prog * prog,const union bpf_attr * attr,union bpf_attr __user * uattr)2323 static int bpf_prog_get_info_by_fd(struct bpf_prog *prog,
2324 const union bpf_attr *attr,
2325 union bpf_attr __user *uattr)
2326 {
2327 struct bpf_prog_info __user *uinfo = u64_to_user_ptr(attr->info.info);
2328 struct bpf_prog_info info = {};
2329 u32 info_len = attr->info.info_len;
2330 struct bpf_prog_stats stats;
2331 char __user *uinsns;
2332 u32 ulen;
2333 int err;
2334
2335 err = bpf_check_uarg_tail_zero(uinfo, sizeof(info), info_len);
2336 if (err)
2337 return err;
2338 info_len = min_t(u32, sizeof(info), info_len);
2339
2340 if (copy_from_user(&info, uinfo, info_len))
2341 return -EFAULT;
2342
2343 info.type = prog->type;
2344 info.id = prog->aux->id;
2345 info.load_time = prog->aux->load_time;
2346 info.created_by_uid = from_kuid_munged(current_user_ns(),
2347 prog->aux->user->uid);
2348 info.gpl_compatible = prog->gpl_compatible;
2349
2350 memcpy(info.tag, prog->tag, sizeof(prog->tag));
2351 memcpy(info.name, prog->aux->name, sizeof(prog->aux->name));
2352
2353 ulen = info.nr_map_ids;
2354 info.nr_map_ids = prog->aux->used_map_cnt;
2355 ulen = min_t(u32, info.nr_map_ids, ulen);
2356 if (ulen) {
2357 u32 __user *user_map_ids = u64_to_user_ptr(info.map_ids);
2358 u32 i;
2359
2360 for (i = 0; i < ulen; i++)
2361 if (put_user(prog->aux->used_maps[i]->id,
2362 &user_map_ids[i]))
2363 return -EFAULT;
2364 }
2365
2366 err = set_info_rec_size(&info);
2367 if (err)
2368 return err;
2369
2370 bpf_prog_get_stats(prog, &stats);
2371 info.run_time_ns = stats.nsecs;
2372 info.run_cnt = stats.cnt;
2373
2374 if (!capable(CAP_SYS_ADMIN)) {
2375 info.jited_prog_len = 0;
2376 info.xlated_prog_len = 0;
2377 info.nr_jited_ksyms = 0;
2378 info.nr_jited_func_lens = 0;
2379 info.nr_func_info = 0;
2380 info.nr_line_info = 0;
2381 info.nr_jited_line_info = 0;
2382 goto done;
2383 }
2384
2385 ulen = info.xlated_prog_len;
2386 info.xlated_prog_len = bpf_prog_insn_size(prog);
2387 if (info.xlated_prog_len && ulen) {
2388 struct bpf_insn *insns_sanitized;
2389 bool fault;
2390
2391 if (prog->blinded && !bpf_dump_raw_ok()) {
2392 info.xlated_prog_insns = 0;
2393 goto done;
2394 }
2395 insns_sanitized = bpf_insn_prepare_dump(prog);
2396 if (!insns_sanitized)
2397 return -ENOMEM;
2398 uinsns = u64_to_user_ptr(info.xlated_prog_insns);
2399 ulen = min_t(u32, info.xlated_prog_len, ulen);
2400 fault = copy_to_user(uinsns, insns_sanitized, ulen);
2401 kfree(insns_sanitized);
2402 if (fault)
2403 return -EFAULT;
2404 }
2405
2406 if (bpf_prog_is_dev_bound(prog->aux)) {
2407 err = bpf_prog_offload_info_fill(&info, prog);
2408 if (err)
2409 return err;
2410 goto done;
2411 }
2412
2413 /* NOTE: the following code is supposed to be skipped for offload.
2414 * bpf_prog_offload_info_fill() is the place to fill similar fields
2415 * for offload.
2416 */
2417 ulen = info.jited_prog_len;
2418 if (prog->aux->func_cnt) {
2419 u32 i;
2420
2421 info.jited_prog_len = 0;
2422 for (i = 0; i < prog->aux->func_cnt; i++)
2423 info.jited_prog_len += prog->aux->func[i]->jited_len;
2424 } else {
2425 info.jited_prog_len = prog->jited_len;
2426 }
2427
2428 if (info.jited_prog_len && ulen) {
2429 if (bpf_dump_raw_ok()) {
2430 uinsns = u64_to_user_ptr(info.jited_prog_insns);
2431 ulen = min_t(u32, info.jited_prog_len, ulen);
2432
2433 /* for multi-function programs, copy the JITed
2434 * instructions for all the functions
2435 */
2436 if (prog->aux->func_cnt) {
2437 u32 len, free, i;
2438 u8 *img;
2439
2440 free = ulen;
2441 for (i = 0; i < prog->aux->func_cnt; i++) {
2442 len = prog->aux->func[i]->jited_len;
2443 len = min_t(u32, len, free);
2444 img = (u8 *) prog->aux->func[i]->bpf_func;
2445 if (copy_to_user(uinsns, img, len))
2446 return -EFAULT;
2447 uinsns += len;
2448 free -= len;
2449 if (!free)
2450 break;
2451 }
2452 } else {
2453 if (copy_to_user(uinsns, prog->bpf_func, ulen))
2454 return -EFAULT;
2455 }
2456 } else {
2457 info.jited_prog_insns = 0;
2458 }
2459 }
2460
2461 ulen = info.nr_jited_ksyms;
2462 info.nr_jited_ksyms = prog->aux->func_cnt ? : 1;
2463 if (ulen) {
2464 if (bpf_dump_raw_ok()) {
2465 unsigned long ksym_addr;
2466 u64 __user *user_ksyms;
2467 u32 i;
2468
2469 /* copy the address of the kernel symbol
2470 * corresponding to each function
2471 */
2472 ulen = min_t(u32, info.nr_jited_ksyms, ulen);
2473 user_ksyms = u64_to_user_ptr(info.jited_ksyms);
2474 if (prog->aux->func_cnt) {
2475 for (i = 0; i < ulen; i++) {
2476 ksym_addr = (unsigned long)
2477 prog->aux->func[i]->bpf_func;
2478 if (put_user((u64) ksym_addr,
2479 &user_ksyms[i]))
2480 return -EFAULT;
2481 }
2482 } else {
2483 ksym_addr = (unsigned long) prog->bpf_func;
2484 if (put_user((u64) ksym_addr, &user_ksyms[0]))
2485 return -EFAULT;
2486 }
2487 } else {
2488 info.jited_ksyms = 0;
2489 }
2490 }
2491
2492 ulen = info.nr_jited_func_lens;
2493 info.nr_jited_func_lens = prog->aux->func_cnt ? : 1;
2494 if (ulen) {
2495 if (bpf_dump_raw_ok()) {
2496 u32 __user *user_lens;
2497 u32 func_len, i;
2498
2499 /* copy the JITed image lengths for each function */
2500 ulen = min_t(u32, info.nr_jited_func_lens, ulen);
2501 user_lens = u64_to_user_ptr(info.jited_func_lens);
2502 if (prog->aux->func_cnt) {
2503 for (i = 0; i < ulen; i++) {
2504 func_len =
2505 prog->aux->func[i]->jited_len;
2506 if (put_user(func_len, &user_lens[i]))
2507 return -EFAULT;
2508 }
2509 } else {
2510 func_len = prog->jited_len;
2511 if (put_user(func_len, &user_lens[0]))
2512 return -EFAULT;
2513 }
2514 } else {
2515 info.jited_func_lens = 0;
2516 }
2517 }
2518
2519 if (prog->aux->btf)
2520 info.btf_id = btf_id(prog->aux->btf);
2521
2522 ulen = info.nr_func_info;
2523 info.nr_func_info = prog->aux->func_info_cnt;
2524 if (info.nr_func_info && ulen) {
2525 char __user *user_finfo;
2526
2527 user_finfo = u64_to_user_ptr(info.func_info);
2528 ulen = min_t(u32, info.nr_func_info, ulen);
2529 if (copy_to_user(user_finfo, prog->aux->func_info,
2530 info.func_info_rec_size * ulen))
2531 return -EFAULT;
2532 }
2533
2534 ulen = info.nr_line_info;
2535 info.nr_line_info = prog->aux->nr_linfo;
2536 if (info.nr_line_info && ulen) {
2537 __u8 __user *user_linfo;
2538
2539 user_linfo = u64_to_user_ptr(info.line_info);
2540 ulen = min_t(u32, info.nr_line_info, ulen);
2541 if (copy_to_user(user_linfo, prog->aux->linfo,
2542 info.line_info_rec_size * ulen))
2543 return -EFAULT;
2544 }
2545
2546 ulen = info.nr_jited_line_info;
2547 if (prog->aux->jited_linfo)
2548 info.nr_jited_line_info = prog->aux->nr_linfo;
2549 else
2550 info.nr_jited_line_info = 0;
2551 if (info.nr_jited_line_info && ulen) {
2552 if (bpf_dump_raw_ok()) {
2553 __u64 __user *user_linfo;
2554 u32 i;
2555
2556 user_linfo = u64_to_user_ptr(info.jited_line_info);
2557 ulen = min_t(u32, info.nr_jited_line_info, ulen);
2558 for (i = 0; i < ulen; i++) {
2559 if (put_user((__u64)(long)prog->aux->jited_linfo[i],
2560 &user_linfo[i]))
2561 return -EFAULT;
2562 }
2563 } else {
2564 info.jited_line_info = 0;
2565 }
2566 }
2567
2568 ulen = info.nr_prog_tags;
2569 info.nr_prog_tags = prog->aux->func_cnt ? : 1;
2570 if (ulen) {
2571 __u8 __user (*user_prog_tags)[BPF_TAG_SIZE];
2572 u32 i;
2573
2574 user_prog_tags = u64_to_user_ptr(info.prog_tags);
2575 ulen = min_t(u32, info.nr_prog_tags, ulen);
2576 if (prog->aux->func_cnt) {
2577 for (i = 0; i < ulen; i++) {
2578 if (copy_to_user(user_prog_tags[i],
2579 prog->aux->func[i]->tag,
2580 BPF_TAG_SIZE))
2581 return -EFAULT;
2582 }
2583 } else {
2584 if (copy_to_user(user_prog_tags[0],
2585 prog->tag, BPF_TAG_SIZE))
2586 return -EFAULT;
2587 }
2588 }
2589
2590 done:
2591 if (copy_to_user(uinfo, &info, info_len) ||
2592 put_user(info_len, &uattr->info.info_len))
2593 return -EFAULT;
2594
2595 return 0;
2596 }
2597
bpf_map_get_info_by_fd(struct bpf_map * map,const union bpf_attr * attr,union bpf_attr __user * uattr)2598 static int bpf_map_get_info_by_fd(struct bpf_map *map,
2599 const union bpf_attr *attr,
2600 union bpf_attr __user *uattr)
2601 {
2602 struct bpf_map_info __user *uinfo = u64_to_user_ptr(attr->info.info);
2603 struct bpf_map_info info = {};
2604 u32 info_len = attr->info.info_len;
2605 int err;
2606
2607 err = bpf_check_uarg_tail_zero(uinfo, sizeof(info), info_len);
2608 if (err)
2609 return err;
2610 info_len = min_t(u32, sizeof(info), info_len);
2611
2612 info.type = map->map_type;
2613 info.id = map->id;
2614 info.key_size = map->key_size;
2615 info.value_size = map->value_size;
2616 info.max_entries = map->max_entries;
2617 info.map_flags = map->map_flags;
2618 memcpy(info.name, map->name, sizeof(map->name));
2619
2620 if (map->btf) {
2621 info.btf_id = btf_id(map->btf);
2622 info.btf_key_type_id = map->btf_key_type_id;
2623 info.btf_value_type_id = map->btf_value_type_id;
2624 }
2625
2626 if (bpf_map_is_dev_bound(map)) {
2627 err = bpf_map_offload_info_fill(&info, map);
2628 if (err)
2629 return err;
2630 }
2631
2632 if (copy_to_user(uinfo, &info, info_len) ||
2633 put_user(info_len, &uattr->info.info_len))
2634 return -EFAULT;
2635
2636 return 0;
2637 }
2638
bpf_btf_get_info_by_fd(struct btf * btf,const union bpf_attr * attr,union bpf_attr __user * uattr)2639 static int bpf_btf_get_info_by_fd(struct btf *btf,
2640 const union bpf_attr *attr,
2641 union bpf_attr __user *uattr)
2642 {
2643 struct bpf_btf_info __user *uinfo = u64_to_user_ptr(attr->info.info);
2644 u32 info_len = attr->info.info_len;
2645 int err;
2646
2647 err = bpf_check_uarg_tail_zero(uinfo, sizeof(*uinfo), info_len);
2648 if (err)
2649 return err;
2650
2651 return btf_get_info_by_fd(btf, attr, uattr);
2652 }
2653
2654 #define BPF_OBJ_GET_INFO_BY_FD_LAST_FIELD info.info
2655
bpf_obj_get_info_by_fd(const union bpf_attr * attr,union bpf_attr __user * uattr)2656 static int bpf_obj_get_info_by_fd(const union bpf_attr *attr,
2657 union bpf_attr __user *uattr)
2658 {
2659 int ufd = attr->info.bpf_fd;
2660 struct fd f;
2661 int err;
2662
2663 if (CHECK_ATTR(BPF_OBJ_GET_INFO_BY_FD))
2664 return -EINVAL;
2665
2666 f = fdget(ufd);
2667 if (!f.file)
2668 return -EBADFD;
2669
2670 if (f.file->f_op == &bpf_prog_fops)
2671 err = bpf_prog_get_info_by_fd(f.file->private_data, attr,
2672 uattr);
2673 else if (f.file->f_op == &bpf_map_fops)
2674 err = bpf_map_get_info_by_fd(f.file->private_data, attr,
2675 uattr);
2676 else if (f.file->f_op == &btf_fops)
2677 err = bpf_btf_get_info_by_fd(f.file->private_data, attr, uattr);
2678 else
2679 err = -EINVAL;
2680
2681 fdput(f);
2682 return err;
2683 }
2684
2685 #define BPF_BTF_LOAD_LAST_FIELD btf_log_level
2686
bpf_btf_load(const union bpf_attr * attr)2687 static int bpf_btf_load(const union bpf_attr *attr)
2688 {
2689 if (CHECK_ATTR(BPF_BTF_LOAD))
2690 return -EINVAL;
2691
2692 if (!capable(CAP_SYS_ADMIN))
2693 return -EPERM;
2694
2695 return btf_new_fd(attr);
2696 }
2697
2698 #define BPF_BTF_GET_FD_BY_ID_LAST_FIELD btf_id
2699
bpf_btf_get_fd_by_id(const union bpf_attr * attr)2700 static int bpf_btf_get_fd_by_id(const union bpf_attr *attr)
2701 {
2702 if (CHECK_ATTR(BPF_BTF_GET_FD_BY_ID))
2703 return -EINVAL;
2704
2705 if (!capable(CAP_SYS_ADMIN))
2706 return -EPERM;
2707
2708 return btf_get_fd_by_id(attr->btf_id);
2709 }
2710
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)2711 static int bpf_task_fd_query_copy(const union bpf_attr *attr,
2712 union bpf_attr __user *uattr,
2713 u32 prog_id, u32 fd_type,
2714 const char *buf, u64 probe_offset,
2715 u64 probe_addr)
2716 {
2717 char __user *ubuf = u64_to_user_ptr(attr->task_fd_query.buf);
2718 u32 len = buf ? strlen(buf) : 0, input_len;
2719 int err = 0;
2720
2721 if (put_user(len, &uattr->task_fd_query.buf_len))
2722 return -EFAULT;
2723 input_len = attr->task_fd_query.buf_len;
2724 if (input_len && ubuf) {
2725 if (!len) {
2726 /* nothing to copy, just make ubuf NULL terminated */
2727 char zero = '\0';
2728
2729 if (put_user(zero, ubuf))
2730 return -EFAULT;
2731 } else if (input_len >= len + 1) {
2732 /* ubuf can hold the string with NULL terminator */
2733 if (copy_to_user(ubuf, buf, len + 1))
2734 return -EFAULT;
2735 } else {
2736 /* ubuf cannot hold the string with NULL terminator,
2737 * do a partial copy with NULL terminator.
2738 */
2739 char zero = '\0';
2740
2741 err = -ENOSPC;
2742 if (copy_to_user(ubuf, buf, input_len - 1))
2743 return -EFAULT;
2744 if (put_user(zero, ubuf + input_len - 1))
2745 return -EFAULT;
2746 }
2747 }
2748
2749 if (put_user(prog_id, &uattr->task_fd_query.prog_id) ||
2750 put_user(fd_type, &uattr->task_fd_query.fd_type) ||
2751 put_user(probe_offset, &uattr->task_fd_query.probe_offset) ||
2752 put_user(probe_addr, &uattr->task_fd_query.probe_addr))
2753 return -EFAULT;
2754
2755 return err;
2756 }
2757
2758 #define BPF_TASK_FD_QUERY_LAST_FIELD task_fd_query.probe_addr
2759
bpf_task_fd_query(const union bpf_attr * attr,union bpf_attr __user * uattr)2760 static int bpf_task_fd_query(const union bpf_attr *attr,
2761 union bpf_attr __user *uattr)
2762 {
2763 pid_t pid = attr->task_fd_query.pid;
2764 u32 fd = attr->task_fd_query.fd;
2765 const struct perf_event *event;
2766 struct files_struct *files;
2767 struct task_struct *task;
2768 struct file *file;
2769 int err;
2770
2771 if (CHECK_ATTR(BPF_TASK_FD_QUERY))
2772 return -EINVAL;
2773
2774 if (!capable(CAP_SYS_ADMIN))
2775 return -EPERM;
2776
2777 if (attr->task_fd_query.flags != 0)
2778 return -EINVAL;
2779
2780 task = get_pid_task(find_vpid(pid), PIDTYPE_PID);
2781 if (!task)
2782 return -ENOENT;
2783
2784 files = get_files_struct(task);
2785 put_task_struct(task);
2786 if (!files)
2787 return -ENOENT;
2788
2789 err = 0;
2790 spin_lock(&files->file_lock);
2791 file = fcheck_files(files, fd);
2792 if (!file)
2793 err = -EBADF;
2794 else
2795 get_file(file);
2796 spin_unlock(&files->file_lock);
2797 put_files_struct(files);
2798
2799 if (err)
2800 goto out;
2801
2802 if (file->f_op == &bpf_raw_tp_fops) {
2803 struct bpf_raw_tracepoint *raw_tp = file->private_data;
2804 struct bpf_raw_event_map *btp = raw_tp->btp;
2805
2806 err = bpf_task_fd_query_copy(attr, uattr,
2807 raw_tp->prog->aux->id,
2808 BPF_FD_TYPE_RAW_TRACEPOINT,
2809 btp->tp->name, 0, 0);
2810 goto put_file;
2811 }
2812
2813 event = perf_get_event(file);
2814 if (!IS_ERR(event)) {
2815 u64 probe_offset, probe_addr;
2816 u32 prog_id, fd_type;
2817 const char *buf;
2818
2819 err = bpf_get_perf_event_info(event, &prog_id, &fd_type,
2820 &buf, &probe_offset,
2821 &probe_addr);
2822 if (!err)
2823 err = bpf_task_fd_query_copy(attr, uattr, prog_id,
2824 fd_type, buf,
2825 probe_offset,
2826 probe_addr);
2827 goto put_file;
2828 }
2829
2830 err = -ENOTSUPP;
2831 put_file:
2832 fput(file);
2833 out:
2834 return err;
2835 }
2836
SYSCALL_DEFINE3(bpf,int,cmd,union bpf_attr __user *,uattr,unsigned int,size)2837 SYSCALL_DEFINE3(bpf, int, cmd, union bpf_attr __user *, uattr, unsigned int, size)
2838 {
2839 union bpf_attr attr = {};
2840 int err;
2841
2842 if (sysctl_unprivileged_bpf_disabled && !capable(CAP_SYS_ADMIN))
2843 return -EPERM;
2844
2845 err = bpf_check_uarg_tail_zero(uattr, sizeof(attr), size);
2846 if (err)
2847 return err;
2848 size = min_t(u32, size, sizeof(attr));
2849
2850 /* copy attributes from user space, may be less than sizeof(bpf_attr) */
2851 if (copy_from_user(&attr, uattr, size) != 0)
2852 return -EFAULT;
2853
2854 err = security_bpf(cmd, &attr, size);
2855 if (err < 0)
2856 return err;
2857
2858 switch (cmd) {
2859 case BPF_MAP_CREATE:
2860 err = map_create(&attr);
2861 break;
2862 case BPF_MAP_LOOKUP_ELEM:
2863 err = map_lookup_elem(&attr);
2864 break;
2865 case BPF_MAP_UPDATE_ELEM:
2866 err = map_update_elem(&attr);
2867 break;
2868 case BPF_MAP_DELETE_ELEM:
2869 err = map_delete_elem(&attr);
2870 break;
2871 case BPF_MAP_GET_NEXT_KEY:
2872 err = map_get_next_key(&attr);
2873 break;
2874 case BPF_MAP_FREEZE:
2875 err = map_freeze(&attr);
2876 break;
2877 case BPF_PROG_LOAD:
2878 err = bpf_prog_load(&attr, uattr);
2879 break;
2880 case BPF_OBJ_PIN:
2881 err = bpf_obj_pin(&attr);
2882 break;
2883 case BPF_OBJ_GET:
2884 err = bpf_obj_get(&attr);
2885 break;
2886 case BPF_PROG_ATTACH:
2887 err = bpf_prog_attach(&attr);
2888 break;
2889 case BPF_PROG_DETACH:
2890 err = bpf_prog_detach(&attr);
2891 break;
2892 case BPF_PROG_QUERY:
2893 err = bpf_prog_query(&attr, uattr);
2894 break;
2895 case BPF_PROG_TEST_RUN:
2896 err = bpf_prog_test_run(&attr, uattr);
2897 break;
2898 case BPF_PROG_GET_NEXT_ID:
2899 err = bpf_obj_get_next_id(&attr, uattr,
2900 &prog_idr, &prog_idr_lock);
2901 break;
2902 case BPF_MAP_GET_NEXT_ID:
2903 err = bpf_obj_get_next_id(&attr, uattr,
2904 &map_idr, &map_idr_lock);
2905 break;
2906 case BPF_BTF_GET_NEXT_ID:
2907 err = bpf_obj_get_next_id(&attr, uattr,
2908 &btf_idr, &btf_idr_lock);
2909 break;
2910 case BPF_PROG_GET_FD_BY_ID:
2911 err = bpf_prog_get_fd_by_id(&attr);
2912 break;
2913 case BPF_MAP_GET_FD_BY_ID:
2914 err = bpf_map_get_fd_by_id(&attr);
2915 break;
2916 case BPF_OBJ_GET_INFO_BY_FD:
2917 err = bpf_obj_get_info_by_fd(&attr, uattr);
2918 break;
2919 case BPF_RAW_TRACEPOINT_OPEN:
2920 err = bpf_raw_tracepoint_open(&attr);
2921 break;
2922 case BPF_BTF_LOAD:
2923 err = bpf_btf_load(&attr);
2924 break;
2925 case BPF_BTF_GET_FD_BY_ID:
2926 err = bpf_btf_get_fd_by_id(&attr);
2927 break;
2928 case BPF_TASK_FD_QUERY:
2929 err = bpf_task_fd_query(&attr, uattr);
2930 break;
2931 case BPF_MAP_LOOKUP_AND_DELETE_ELEM:
2932 err = map_lookup_and_delete_elem(&attr);
2933 break;
2934 default:
2935 err = -EINVAL;
2936 break;
2937 }
2938
2939 return err;
2940 }
2941