]> git.proxmox.com Git - mirror_ubuntu-hirsute-kernel.git/blame - kernel/bpf/cgroup.c
Merge branch 'improve_perf_barriers'
[mirror_ubuntu-hirsute-kernel.git] / kernel / bpf / cgroup.c
CommitLineData
30070984
DM
1/*
2 * Functions to manage eBPF programs attached to cgroups
3 *
4 * Copyright (c) 2016 Daniel Mack
5 *
6 * This file is subject to the terms and conditions of version 2 of the GNU
7 * General Public License. See the file COPYING in the main directory of the
8 * Linux distribution for more details.
9 */
10
11#include <linux/kernel.h>
12#include <linux/atomic.h>
13#include <linux/cgroup.h>
14#include <linux/slab.h>
15#include <linux/bpf.h>
16#include <linux/bpf-cgroup.h>
17#include <net/sock.h>
18
19DEFINE_STATIC_KEY_FALSE(cgroup_bpf_enabled_key);
20EXPORT_SYMBOL(cgroup_bpf_enabled_key);
21
22/**
23 * cgroup_bpf_put() - put references of all bpf programs
24 * @cgrp: the cgroup to modify
25 */
26void cgroup_bpf_put(struct cgroup *cgrp)
27{
8bad74f9 28 enum bpf_cgroup_storage_type stype;
30070984
DM
29 unsigned int type;
30
324bda9e
AS
31 for (type = 0; type < ARRAY_SIZE(cgrp->bpf.progs); type++) {
32 struct list_head *progs = &cgrp->bpf.progs[type];
33 struct bpf_prog_list *pl, *tmp;
34
35 list_for_each_entry_safe(pl, tmp, progs, node) {
36 list_del(&pl->node);
37 bpf_prog_put(pl->prog);
8bad74f9
RG
38 for_each_cgroup_storage_type(stype) {
39 bpf_cgroup_storage_unlink(pl->storage[stype]);
40 bpf_cgroup_storage_free(pl->storage[stype]);
41 }
324bda9e 42 kfree(pl);
30070984
DM
43 static_branch_dec(&cgroup_bpf_enabled_key);
44 }
324bda9e
AS
45 bpf_prog_array_free(cgrp->bpf.effective[type]);
46 }
47}
48
49/* count number of elements in the list.
50 * it's slow but the list cannot be long
51 */
52static u32 prog_list_length(struct list_head *head)
53{
54 struct bpf_prog_list *pl;
55 u32 cnt = 0;
56
57 list_for_each_entry(pl, head, node) {
58 if (!pl->prog)
59 continue;
60 cnt++;
30070984 61 }
324bda9e
AS
62 return cnt;
63}
64
65/* if parent has non-overridable prog attached,
66 * disallow attaching new programs to the descendent cgroup.
67 * if parent has overridable or multi-prog, allow attaching
68 */
69static bool hierarchy_allows_attach(struct cgroup *cgrp,
70 enum bpf_attach_type type,
71 u32 new_flags)
72{
73 struct cgroup *p;
74
75 p = cgroup_parent(cgrp);
76 if (!p)
77 return true;
78 do {
79 u32 flags = p->bpf.flags[type];
80 u32 cnt;
81
82 if (flags & BPF_F_ALLOW_MULTI)
83 return true;
84 cnt = prog_list_length(&p->bpf.progs[type]);
85 WARN_ON_ONCE(cnt > 1);
86 if (cnt == 1)
87 return !!(flags & BPF_F_ALLOW_OVERRIDE);
88 p = cgroup_parent(p);
89 } while (p);
90 return true;
91}
92
93/* compute a chain of effective programs for a given cgroup:
94 * start from the list of programs in this cgroup and add
95 * all parent programs.
96 * Note that parent's F_ALLOW_OVERRIDE-type program is yielding
97 * to programs in this cgroup
98 */
99static int compute_effective_progs(struct cgroup *cgrp,
100 enum bpf_attach_type type,
101 struct bpf_prog_array __rcu **array)
102{
8bad74f9 103 enum bpf_cgroup_storage_type stype;
3960f4fd 104 struct bpf_prog_array *progs;
324bda9e
AS
105 struct bpf_prog_list *pl;
106 struct cgroup *p = cgrp;
107 int cnt = 0;
108
109 /* count number of effective programs by walking parents */
110 do {
111 if (cnt == 0 || (p->bpf.flags[type] & BPF_F_ALLOW_MULTI))
112 cnt += prog_list_length(&p->bpf.progs[type]);
113 p = cgroup_parent(p);
114 } while (p);
115
116 progs = bpf_prog_array_alloc(cnt, GFP_KERNEL);
117 if (!progs)
118 return -ENOMEM;
119
120 /* populate the array with effective progs */
121 cnt = 0;
122 p = cgrp;
123 do {
394e40a2
RG
124 if (cnt > 0 && !(p->bpf.flags[type] & BPF_F_ALLOW_MULTI))
125 continue;
126
127 list_for_each_entry(pl, &p->bpf.progs[type], node) {
128 if (!pl->prog)
129 continue;
130
131 progs->items[cnt].prog = pl->prog;
8bad74f9
RG
132 for_each_cgroup_storage_type(stype)
133 progs->items[cnt].cgroup_storage[stype] =
134 pl->storage[stype];
394e40a2
RG
135 cnt++;
136 }
137 } while ((p = cgroup_parent(p)));
324bda9e 138
3960f4fd 139 rcu_assign_pointer(*array, progs);
324bda9e
AS
140 return 0;
141}
142
143static void activate_effective_progs(struct cgroup *cgrp,
144 enum bpf_attach_type type,
145 struct bpf_prog_array __rcu *array)
146{
147 struct bpf_prog_array __rcu *old_array;
148
149 old_array = xchg(&cgrp->bpf.effective[type], array);
150 /* free prog array after grace period, since __cgroup_bpf_run_*()
151 * might be still walking the array
152 */
153 bpf_prog_array_free(old_array);
30070984
DM
154}
155
156/**
157 * cgroup_bpf_inherit() - inherit effective programs from parent
158 * @cgrp: the cgroup to modify
30070984 159 */
324bda9e 160int cgroup_bpf_inherit(struct cgroup *cgrp)
30070984 161{
324bda9e
AS
162/* has to use marco instead of const int, since compiler thinks
163 * that array below is variable length
164 */
165#define NR ARRAY_SIZE(cgrp->bpf.effective)
166 struct bpf_prog_array __rcu *arrays[NR] = {};
167 int i;
30070984 168
324bda9e
AS
169 for (i = 0; i < NR; i++)
170 INIT_LIST_HEAD(&cgrp->bpf.progs[i]);
30070984 171
324bda9e
AS
172 for (i = 0; i < NR; i++)
173 if (compute_effective_progs(cgrp, i, &arrays[i]))
174 goto cleanup;
175
176 for (i = 0; i < NR; i++)
177 activate_effective_progs(cgrp, i, arrays[i]);
178
179 return 0;
180cleanup:
181 for (i = 0; i < NR; i++)
182 bpf_prog_array_free(arrays[i]);
183 return -ENOMEM;
30070984
DM
184}
185
85fc4b16
RG
186static int update_effective_progs(struct cgroup *cgrp,
187 enum bpf_attach_type type)
188{
189 struct cgroup_subsys_state *css;
190 int err;
191
192 /* allocate and recompute effective prog arrays */
193 css_for_each_descendant_pre(css, &cgrp->self) {
194 struct cgroup *desc = container_of(css, struct cgroup, self);
195
196 err = compute_effective_progs(desc, type, &desc->bpf.inactive);
197 if (err)
198 goto cleanup;
199 }
200
201 /* all allocations were successful. Activate all prog arrays */
202 css_for_each_descendant_pre(css, &cgrp->self) {
203 struct cgroup *desc = container_of(css, struct cgroup, self);
204
205 activate_effective_progs(desc, type, desc->bpf.inactive);
206 desc->bpf.inactive = NULL;
207 }
208
209 return 0;
210
211cleanup:
212 /* oom while computing effective. Free all computed effective arrays
213 * since they were not activated
214 */
215 css_for_each_descendant_pre(css, &cgrp->self) {
216 struct cgroup *desc = container_of(css, struct cgroup, self);
217
218 bpf_prog_array_free(desc->bpf.inactive);
219 desc->bpf.inactive = NULL;
220 }
221
222 return err;
223}
224
324bda9e
AS
225#define BPF_CGROUP_MAX_PROGS 64
226
30070984 227/**
324bda9e 228 * __cgroup_bpf_attach() - Attach the program to a cgroup, and
30070984
DM
229 * propagate the change to descendants
230 * @cgrp: The cgroup which descendants to traverse
324bda9e
AS
231 * @prog: A program to attach
232 * @type: Type of attach operation
30070984
DM
233 *
234 * Must be called with cgroup_mutex held.
235 */
324bda9e
AS
236int __cgroup_bpf_attach(struct cgroup *cgrp, struct bpf_prog *prog,
237 enum bpf_attach_type type, u32 flags)
30070984 238{
324bda9e
AS
239 struct list_head *progs = &cgrp->bpf.progs[type];
240 struct bpf_prog *old_prog = NULL;
8bad74f9
RG
241 struct bpf_cgroup_storage *storage[MAX_BPF_CGROUP_STORAGE_TYPE],
242 *old_storage[MAX_BPF_CGROUP_STORAGE_TYPE] = {NULL};
243 enum bpf_cgroup_storage_type stype;
324bda9e
AS
244 struct bpf_prog_list *pl;
245 bool pl_was_allocated;
324bda9e
AS
246 int err;
247
248 if ((flags & BPF_F_ALLOW_OVERRIDE) && (flags & BPF_F_ALLOW_MULTI))
249 /* invalid combination */
250 return -EINVAL;
251
252 if (!hierarchy_allows_attach(cgrp, type, flags))
7f677633
AS
253 return -EPERM;
254
324bda9e
AS
255 if (!list_empty(progs) && cgrp->bpf.flags[type] != flags)
256 /* Disallow attaching non-overridable on top
257 * of existing overridable in this cgroup.
258 * Disallow attaching multi-prog if overridable or none
7f677633
AS
259 */
260 return -EPERM;
261
324bda9e
AS
262 if (prog_list_length(progs) >= BPF_CGROUP_MAX_PROGS)
263 return -E2BIG;
264
8bad74f9
RG
265 for_each_cgroup_storage_type(stype) {
266 storage[stype] = bpf_cgroup_storage_alloc(prog, stype);
267 if (IS_ERR(storage[stype])) {
268 storage[stype] = NULL;
269 for_each_cgroup_storage_type(stype)
270 bpf_cgroup_storage_free(storage[stype]);
271 return -ENOMEM;
272 }
273 }
d7bf2c10 274
324bda9e 275 if (flags & BPF_F_ALLOW_MULTI) {
d7bf2c10
RG
276 list_for_each_entry(pl, progs, node) {
277 if (pl->prog == prog) {
324bda9e 278 /* disallow attaching the same prog twice */
8bad74f9
RG
279 for_each_cgroup_storage_type(stype)
280 bpf_cgroup_storage_free(storage[stype]);
324bda9e 281 return -EINVAL;
d7bf2c10
RG
282 }
283 }
324bda9e
AS
284
285 pl = kmalloc(sizeof(*pl), GFP_KERNEL);
d7bf2c10 286 if (!pl) {
8bad74f9
RG
287 for_each_cgroup_storage_type(stype)
288 bpf_cgroup_storage_free(storage[stype]);
324bda9e 289 return -ENOMEM;
d7bf2c10
RG
290 }
291
324bda9e
AS
292 pl_was_allocated = true;
293 pl->prog = prog;
8bad74f9
RG
294 for_each_cgroup_storage_type(stype)
295 pl->storage[stype] = storage[stype];
324bda9e
AS
296 list_add_tail(&pl->node, progs);
297 } else {
298 if (list_empty(progs)) {
299 pl = kmalloc(sizeof(*pl), GFP_KERNEL);
d7bf2c10 300 if (!pl) {
8bad74f9
RG
301 for_each_cgroup_storage_type(stype)
302 bpf_cgroup_storage_free(storage[stype]);
324bda9e 303 return -ENOMEM;
d7bf2c10 304 }
324bda9e
AS
305 pl_was_allocated = true;
306 list_add_tail(&pl->node, progs);
307 } else {
308 pl = list_first_entry(progs, typeof(*pl), node);
309 old_prog = pl->prog;
8bad74f9
RG
310 for_each_cgroup_storage_type(stype) {
311 old_storage[stype] = pl->storage[stype];
312 bpf_cgroup_storage_unlink(old_storage[stype]);
313 }
324bda9e
AS
314 pl_was_allocated = false;
315 }
316 pl->prog = prog;
8bad74f9
RG
317 for_each_cgroup_storage_type(stype)
318 pl->storage[stype] = storage[stype];
7f677633 319 }
30070984 320
324bda9e 321 cgrp->bpf.flags[type] = flags;
7f677633 322
85fc4b16
RG
323 err = update_effective_progs(cgrp, type);
324 if (err)
325 goto cleanup;
324bda9e
AS
326
327 static_branch_inc(&cgroup_bpf_enabled_key);
8bad74f9
RG
328 for_each_cgroup_storage_type(stype) {
329 if (!old_storage[stype])
330 continue;
331 bpf_cgroup_storage_free(old_storage[stype]);
332 }
30070984
DM
333 if (old_prog) {
334 bpf_prog_put(old_prog);
335 static_branch_dec(&cgroup_bpf_enabled_key);
336 }
8bad74f9
RG
337 for_each_cgroup_storage_type(stype)
338 bpf_cgroup_storage_link(storage[stype], cgrp, type);
7f677633 339 return 0;
324bda9e
AS
340
341cleanup:
324bda9e
AS
342 /* and cleanup the prog list */
343 pl->prog = old_prog;
8bad74f9
RG
344 for_each_cgroup_storage_type(stype) {
345 bpf_cgroup_storage_free(pl->storage[stype]);
346 pl->storage[stype] = old_storage[stype];
347 bpf_cgroup_storage_link(old_storage[stype], cgrp, type);
348 }
324bda9e
AS
349 if (pl_was_allocated) {
350 list_del(&pl->node);
351 kfree(pl);
352 }
353 return err;
354}
355
356/**
357 * __cgroup_bpf_detach() - Detach the program from a cgroup, and
358 * propagate the change to descendants
359 * @cgrp: The cgroup which descendants to traverse
360 * @prog: A program to detach or NULL
361 * @type: Type of detach operation
362 *
363 * Must be called with cgroup_mutex held.
364 */
365int __cgroup_bpf_detach(struct cgroup *cgrp, struct bpf_prog *prog,
366 enum bpf_attach_type type, u32 unused_flags)
367{
368 struct list_head *progs = &cgrp->bpf.progs[type];
8bad74f9 369 enum bpf_cgroup_storage_type stype;
324bda9e
AS
370 u32 flags = cgrp->bpf.flags[type];
371 struct bpf_prog *old_prog = NULL;
324bda9e
AS
372 struct bpf_prog_list *pl;
373 int err;
374
375 if (flags & BPF_F_ALLOW_MULTI) {
376 if (!prog)
377 /* to detach MULTI prog the user has to specify valid FD
378 * of the program to be detached
379 */
380 return -EINVAL;
381 } else {
382 if (list_empty(progs))
383 /* report error when trying to detach and nothing is attached */
384 return -ENOENT;
385 }
386
387 if (flags & BPF_F_ALLOW_MULTI) {
388 /* find the prog and detach it */
389 list_for_each_entry(pl, progs, node) {
390 if (pl->prog != prog)
391 continue;
392 old_prog = prog;
393 /* mark it deleted, so it's ignored while
394 * recomputing effective
395 */
396 pl->prog = NULL;
397 break;
398 }
399 if (!old_prog)
400 return -ENOENT;
401 } else {
402 /* to maintain backward compatibility NONE and OVERRIDE cgroups
403 * allow detaching with invalid FD (prog==NULL)
404 */
405 pl = list_first_entry(progs, typeof(*pl), node);
406 old_prog = pl->prog;
407 pl->prog = NULL;
408 }
409
85fc4b16
RG
410 err = update_effective_progs(cgrp, type);
411 if (err)
412 goto cleanup;
324bda9e
AS
413
414 /* now can actually delete it from this cgroup list */
415 list_del(&pl->node);
8bad74f9
RG
416 for_each_cgroup_storage_type(stype) {
417 bpf_cgroup_storage_unlink(pl->storage[stype]);
418 bpf_cgroup_storage_free(pl->storage[stype]);
419 }
324bda9e
AS
420 kfree(pl);
421 if (list_empty(progs))
422 /* last program was detached, reset flags to zero */
423 cgrp->bpf.flags[type] = 0;
424
425 bpf_prog_put(old_prog);
426 static_branch_dec(&cgroup_bpf_enabled_key);
427 return 0;
428
429cleanup:
324bda9e
AS
430 /* and restore back old_prog */
431 pl->prog = old_prog;
432 return err;
30070984
DM
433}
434
468e2f64
AS
435/* Must be called with cgroup_mutex held to avoid races. */
436int __cgroup_bpf_query(struct cgroup *cgrp, const union bpf_attr *attr,
437 union bpf_attr __user *uattr)
438{
439 __u32 __user *prog_ids = u64_to_user_ptr(attr->query.prog_ids);
440 enum bpf_attach_type type = attr->query.attach_type;
441 struct list_head *progs = &cgrp->bpf.progs[type];
442 u32 flags = cgrp->bpf.flags[type];
443 int cnt, ret = 0, i;
444
445 if (attr->query.query_flags & BPF_F_QUERY_EFFECTIVE)
446 cnt = bpf_prog_array_length(cgrp->bpf.effective[type]);
447 else
448 cnt = prog_list_length(progs);
449
450 if (copy_to_user(&uattr->query.attach_flags, &flags, sizeof(flags)))
451 return -EFAULT;
452 if (copy_to_user(&uattr->query.prog_cnt, &cnt, sizeof(cnt)))
453 return -EFAULT;
454 if (attr->query.prog_cnt == 0 || !prog_ids || !cnt)
455 /* return early if user requested only program count + flags */
456 return 0;
457 if (attr->query.prog_cnt < cnt) {
458 cnt = attr->query.prog_cnt;
459 ret = -ENOSPC;
460 }
461
462 if (attr->query.query_flags & BPF_F_QUERY_EFFECTIVE) {
463 return bpf_prog_array_copy_to_user(cgrp->bpf.effective[type],
464 prog_ids, cnt);
465 } else {
466 struct bpf_prog_list *pl;
467 u32 id;
468
469 i = 0;
470 list_for_each_entry(pl, progs, node) {
471 id = pl->prog->aux->id;
472 if (copy_to_user(prog_ids + i, &id, sizeof(id)))
473 return -EFAULT;
474 if (++i == cnt)
475 break;
476 }
477 }
478 return ret;
479}
480
fdb5c453
SY
481int cgroup_bpf_prog_attach(const union bpf_attr *attr,
482 enum bpf_prog_type ptype, struct bpf_prog *prog)
483{
484 struct cgroup *cgrp;
485 int ret;
486
487 cgrp = cgroup_get_from_fd(attr->target_fd);
488 if (IS_ERR(cgrp))
489 return PTR_ERR(cgrp);
490
491 ret = cgroup_bpf_attach(cgrp, prog, attr->attach_type,
492 attr->attach_flags);
493 cgroup_put(cgrp);
494 return ret;
495}
496
497int cgroup_bpf_prog_detach(const union bpf_attr *attr, enum bpf_prog_type ptype)
498{
499 struct bpf_prog *prog;
500 struct cgroup *cgrp;
501 int ret;
502
503 cgrp = cgroup_get_from_fd(attr->target_fd);
504 if (IS_ERR(cgrp))
505 return PTR_ERR(cgrp);
506
507 prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype);
508 if (IS_ERR(prog))
509 prog = NULL;
510
511 ret = cgroup_bpf_detach(cgrp, prog, attr->attach_type, 0);
512 if (prog)
513 bpf_prog_put(prog);
514
515 cgroup_put(cgrp);
516 return ret;
517}
518
519int cgroup_bpf_prog_query(const union bpf_attr *attr,
520 union bpf_attr __user *uattr)
521{
522 struct cgroup *cgrp;
523 int ret;
524
525 cgrp = cgroup_get_from_fd(attr->query.target_fd);
526 if (IS_ERR(cgrp))
527 return PTR_ERR(cgrp);
528
529 ret = cgroup_bpf_query(cgrp, attr, uattr);
530
531 cgroup_put(cgrp);
532 return ret;
533}
534
30070984 535/**
b2cd1257 536 * __cgroup_bpf_run_filter_skb() - Run a program for packet filtering
8f917bba 537 * @sk: The socket sending or receiving traffic
30070984
DM
538 * @skb: The skb that is being sent or received
539 * @type: The type of program to be exectuted
540 *
541 * If no socket is passed, or the socket is not of type INET or INET6,
542 * this function does nothing and returns 0.
543 *
544 * The program type passed in via @type must be suitable for network
545 * filtering. No further check is performed to assert that.
546 *
547 * This function will return %-EPERM if any if an attached program was found
548 * and if it returned != 1 during execution. In all other cases, 0 is returned.
549 */
b2cd1257
DA
550int __cgroup_bpf_run_filter_skb(struct sock *sk,
551 struct sk_buff *skb,
552 enum bpf_attach_type type)
30070984 553{
324bda9e
AS
554 unsigned int offset = skb->data - skb_network_header(skb);
555 struct sock *save_sk;
30070984 556 struct cgroup *cgrp;
324bda9e 557 int ret;
30070984
DM
558
559 if (!sk || !sk_fullsock(sk))
560 return 0;
561
324bda9e 562 if (sk->sk_family != AF_INET && sk->sk_family != AF_INET6)
30070984
DM
563 return 0;
564
565 cgrp = sock_cgroup_ptr(&sk->sk_cgrp_data);
324bda9e
AS
566 save_sk = skb->sk;
567 skb->sk = sk;
568 __skb_push(skb, offset);
569 ret = BPF_PROG_RUN_ARRAY(cgrp->bpf.effective[type], skb,
570 bpf_prog_run_save_cb);
571 __skb_pull(skb, offset);
572 skb->sk = save_sk;
573 return ret == 1 ? 0 : -EPERM;
30070984 574}
b2cd1257 575EXPORT_SYMBOL(__cgroup_bpf_run_filter_skb);
61023658
DA
576
577/**
578 * __cgroup_bpf_run_filter_sk() - Run a program on a sock
579 * @sk: sock structure to manipulate
580 * @type: The type of program to be exectuted
581 *
582 * socket is passed is expected to be of type INET or INET6.
583 *
584 * The program type passed in via @type must be suitable for sock
585 * filtering. No further check is performed to assert that.
586 *
587 * This function will return %-EPERM if any if an attached program was found
588 * and if it returned != 1 during execution. In all other cases, 0 is returned.
589 */
590int __cgroup_bpf_run_filter_sk(struct sock *sk,
591 enum bpf_attach_type type)
592{
593 struct cgroup *cgrp = sock_cgroup_ptr(&sk->sk_cgrp_data);
324bda9e 594 int ret;
61023658 595
324bda9e
AS
596 ret = BPF_PROG_RUN_ARRAY(cgrp->bpf.effective[type], sk, BPF_PROG_RUN);
597 return ret == 1 ? 0 : -EPERM;
61023658
DA
598}
599EXPORT_SYMBOL(__cgroup_bpf_run_filter_sk);
40304b2a 600
4fbac77d
AI
601/**
602 * __cgroup_bpf_run_filter_sock_addr() - Run a program on a sock and
603 * provided by user sockaddr
604 * @sk: sock struct that will use sockaddr
605 * @uaddr: sockaddr struct provided by user
606 * @type: The type of program to be exectuted
1cedee13 607 * @t_ctx: Pointer to attach type specific context
4fbac77d
AI
608 *
609 * socket is expected to be of type INET or INET6.
610 *
611 * This function will return %-EPERM if an attached program is found and
612 * returned value != 1 during execution. In all other cases, 0 is returned.
613 */
614int __cgroup_bpf_run_filter_sock_addr(struct sock *sk,
615 struct sockaddr *uaddr,
1cedee13
AI
616 enum bpf_attach_type type,
617 void *t_ctx)
4fbac77d
AI
618{
619 struct bpf_sock_addr_kern ctx = {
620 .sk = sk,
621 .uaddr = uaddr,
1cedee13 622 .t_ctx = t_ctx,
4fbac77d 623 };
1cedee13 624 struct sockaddr_storage unspec;
4fbac77d
AI
625 struct cgroup *cgrp;
626 int ret;
627
628 /* Check socket family since not all sockets represent network
629 * endpoint (e.g. AF_UNIX).
630 */
631 if (sk->sk_family != AF_INET && sk->sk_family != AF_INET6)
632 return 0;
633
1cedee13
AI
634 if (!ctx.uaddr) {
635 memset(&unspec, 0, sizeof(unspec));
636 ctx.uaddr = (struct sockaddr *)&unspec;
637 }
638
4fbac77d
AI
639 cgrp = sock_cgroup_ptr(&sk->sk_cgrp_data);
640 ret = BPF_PROG_RUN_ARRAY(cgrp->bpf.effective[type], &ctx, BPF_PROG_RUN);
641
642 return ret == 1 ? 0 : -EPERM;
643}
644EXPORT_SYMBOL(__cgroup_bpf_run_filter_sock_addr);
645
40304b2a
LB
646/**
647 * __cgroup_bpf_run_filter_sock_ops() - Run a program on a sock
648 * @sk: socket to get cgroup from
649 * @sock_ops: bpf_sock_ops_kern struct to pass to program. Contains
650 * sk with connection information (IP addresses, etc.) May not contain
651 * cgroup info if it is a req sock.
652 * @type: The type of program to be exectuted
653 *
654 * socket passed is expected to be of type INET or INET6.
655 *
656 * The program type passed in via @type must be suitable for sock_ops
657 * filtering. No further check is performed to assert that.
658 *
659 * This function will return %-EPERM if any if an attached program was found
660 * and if it returned != 1 during execution. In all other cases, 0 is returned.
661 */
662int __cgroup_bpf_run_filter_sock_ops(struct sock *sk,
663 struct bpf_sock_ops_kern *sock_ops,
664 enum bpf_attach_type type)
665{
666 struct cgroup *cgrp = sock_cgroup_ptr(&sk->sk_cgrp_data);
324bda9e 667 int ret;
40304b2a 668
324bda9e
AS
669 ret = BPF_PROG_RUN_ARRAY(cgrp->bpf.effective[type], sock_ops,
670 BPF_PROG_RUN);
671 return ret == 1 ? 0 : -EPERM;
40304b2a
LB
672}
673EXPORT_SYMBOL(__cgroup_bpf_run_filter_sock_ops);
ebc614f6
RG
674
675int __cgroup_bpf_check_dev_permission(short dev_type, u32 major, u32 minor,
676 short access, enum bpf_attach_type type)
677{
678 struct cgroup *cgrp;
679 struct bpf_cgroup_dev_ctx ctx = {
680 .access_type = (access << 16) | dev_type,
681 .major = major,
682 .minor = minor,
683 };
684 int allow = 1;
685
686 rcu_read_lock();
687 cgrp = task_dfl_cgroup(current);
688 allow = BPF_PROG_RUN_ARRAY(cgrp->bpf.effective[type], &ctx,
689 BPF_PROG_RUN);
690 rcu_read_unlock();
691
692 return !allow;
693}
694EXPORT_SYMBOL(__cgroup_bpf_check_dev_permission);
695
696static const struct bpf_func_proto *
5e43f899 697cgroup_dev_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
ebc614f6
RG
698{
699 switch (func_id) {
700 case BPF_FUNC_map_lookup_elem:
701 return &bpf_map_lookup_elem_proto;
702 case BPF_FUNC_map_update_elem:
703 return &bpf_map_update_elem_proto;
704 case BPF_FUNC_map_delete_elem:
705 return &bpf_map_delete_elem_proto;
706 case BPF_FUNC_get_current_uid_gid:
707 return &bpf_get_current_uid_gid_proto;
cd339431
RG
708 case BPF_FUNC_get_local_storage:
709 return &bpf_get_local_storage_proto;
5bf7a60b
YS
710 case BPF_FUNC_get_current_cgroup_id:
711 return &bpf_get_current_cgroup_id_proto;
ebc614f6
RG
712 case BPF_FUNC_trace_printk:
713 if (capable(CAP_SYS_ADMIN))
714 return bpf_get_trace_printk_proto();
715 default:
716 return NULL;
717 }
718}
719
720static bool cgroup_dev_is_valid_access(int off, int size,
721 enum bpf_access_type type,
5e43f899 722 const struct bpf_prog *prog,
ebc614f6
RG
723 struct bpf_insn_access_aux *info)
724{
06ef0ccb
YS
725 const int size_default = sizeof(__u32);
726
ebc614f6
RG
727 if (type == BPF_WRITE)
728 return false;
729
730 if (off < 0 || off + size > sizeof(struct bpf_cgroup_dev_ctx))
731 return false;
732 /* The verifier guarantees that size > 0. */
733 if (off % size != 0)
734 return false;
06ef0ccb
YS
735
736 switch (off) {
737 case bpf_ctx_range(struct bpf_cgroup_dev_ctx, access_type):
738 bpf_ctx_record_field_size(info, size_default);
739 if (!bpf_ctx_narrow_access_ok(off, size, size_default))
740 return false;
741 break;
742 default:
743 if (size != size_default)
744 return false;
745 }
ebc614f6
RG
746
747 return true;
748}
749
750const struct bpf_prog_ops cg_dev_prog_ops = {
751};
752
753const struct bpf_verifier_ops cg_dev_verifier_ops = {
754 .get_func_proto = cgroup_dev_func_proto,
755 .is_valid_access = cgroup_dev_is_valid_access,
756};