1/* SPDX-License-Identifier: GPL-2.0 */
2#ifndef _BPF_CGROUP_H
3#define _BPF_CGROUP_H
4
5#include <linux/bpf.h>
6#include <linux/bpf-cgroup-defs.h>
7#include <linux/errno.h>
8#include <linux/jump_label.h>
9#include <linux/percpu.h>
10#include <linux/rbtree.h>
11#include <net/sock.h>
12#include <uapi/linux/bpf.h>
13
14struct sock;
15struct sockaddr;
16struct cgroup;
17struct sk_buff;
18struct bpf_map;
19struct bpf_prog;
20struct bpf_sock_ops_kern;
21struct bpf_cgroup_storage;
22struct ctl_table;
23struct ctl_table_header;
24struct task_struct;
25
26unsigned int __cgroup_bpf_run_lsm_sock(const void *ctx,
27 const struct bpf_insn *insn);
28unsigned int __cgroup_bpf_run_lsm_socket(const void *ctx,
29 const struct bpf_insn *insn);
30unsigned int __cgroup_bpf_run_lsm_current(const void *ctx,
31 const struct bpf_insn *insn);
32
33#ifdef CONFIG_CGROUP_BPF
34
35#define CGROUP_ATYPE(type) \
36 case BPF_##type: return type
37
38static inline enum cgroup_bpf_attach_type
39to_cgroup_bpf_attach_type(enum bpf_attach_type attach_type)
40{
41 switch (attach_type) {
42 CGROUP_ATYPE(CGROUP_INET_INGRESS);
43 CGROUP_ATYPE(CGROUP_INET_EGRESS);
44 CGROUP_ATYPE(CGROUP_INET_SOCK_CREATE);
45 CGROUP_ATYPE(CGROUP_SOCK_OPS);
46 CGROUP_ATYPE(CGROUP_DEVICE);
47 CGROUP_ATYPE(CGROUP_INET4_BIND);
48 CGROUP_ATYPE(CGROUP_INET6_BIND);
49 CGROUP_ATYPE(CGROUP_INET4_CONNECT);
50 CGROUP_ATYPE(CGROUP_INET6_CONNECT);
51 CGROUP_ATYPE(CGROUP_INET4_POST_BIND);
52 CGROUP_ATYPE(CGROUP_INET6_POST_BIND);
53 CGROUP_ATYPE(CGROUP_UDP4_SENDMSG);
54 CGROUP_ATYPE(CGROUP_UDP6_SENDMSG);
55 CGROUP_ATYPE(CGROUP_SYSCTL);
56 CGROUP_ATYPE(CGROUP_UDP4_RECVMSG);
57 CGROUP_ATYPE(CGROUP_UDP6_RECVMSG);
58 CGROUP_ATYPE(CGROUP_GETSOCKOPT);
59 CGROUP_ATYPE(CGROUP_SETSOCKOPT);
60 CGROUP_ATYPE(CGROUP_INET4_GETPEERNAME);
61 CGROUP_ATYPE(CGROUP_INET6_GETPEERNAME);
62 CGROUP_ATYPE(CGROUP_INET4_GETSOCKNAME);
63 CGROUP_ATYPE(CGROUP_INET6_GETSOCKNAME);
64 CGROUP_ATYPE(CGROUP_INET_SOCK_RELEASE);
65 default:
66 return CGROUP_BPF_ATTACH_TYPE_INVALID;
67 }
68}
69
70#undef CGROUP_ATYPE
71
72extern struct static_key_false cgroup_bpf_enabled_key[MAX_CGROUP_BPF_ATTACH_TYPE];
73#define cgroup_bpf_enabled(atype) static_branch_unlikely(&cgroup_bpf_enabled_key[atype])
74
75#define for_each_cgroup_storage_type(stype) \
76 for (stype = 0; stype < MAX_BPF_CGROUP_STORAGE_TYPE; stype++)
77
78struct bpf_cgroup_storage_map;
79
80struct bpf_storage_buffer {
81 struct rcu_head rcu;
82 char data[];
83};
84
85struct bpf_cgroup_storage {
86 union {
87 struct bpf_storage_buffer *buf;
88 void __percpu *percpu_buf;
89 };
90 struct bpf_cgroup_storage_map *map;
91 struct bpf_cgroup_storage_key key;
92 struct list_head list_map;
93 struct list_head list_cg;
94 struct rb_node node;
95 struct rcu_head rcu;
96};
97
98struct bpf_cgroup_link {
99 struct bpf_link link;
100 struct cgroup *cgroup;
101 enum bpf_attach_type type;
102};
103
104struct bpf_prog_list {
105 struct hlist_node node;
106 struct bpf_prog *prog;
107 struct bpf_cgroup_link *link;
108 struct bpf_cgroup_storage *storage[MAX_BPF_CGROUP_STORAGE_TYPE];
109};
110
111int cgroup_bpf_inherit(struct cgroup *cgrp);
112void cgroup_bpf_offline(struct cgroup *cgrp);
113
114int __cgroup_bpf_run_filter_skb(struct sock *sk,
115 struct sk_buff *skb,
116 enum cgroup_bpf_attach_type atype);
117
118int __cgroup_bpf_run_filter_sk(struct sock *sk,
119 enum cgroup_bpf_attach_type atype);
120
121int __cgroup_bpf_run_filter_sock_addr(struct sock *sk,
122 struct sockaddr *uaddr,
123 enum cgroup_bpf_attach_type atype,
124 void *t_ctx,
125 u32 *flags);
126
127int __cgroup_bpf_run_filter_sock_ops(struct sock *sk,
128 struct bpf_sock_ops_kern *sock_ops,
129 enum cgroup_bpf_attach_type atype);
130
131int __cgroup_bpf_check_dev_permission(short dev_type, u32 major, u32 minor,
132 short access, enum cgroup_bpf_attach_type atype);
133
134int __cgroup_bpf_run_filter_sysctl(struct ctl_table_header *head,
135 struct ctl_table *table, int write,
136 char **buf, size_t *pcount, loff_t *ppos,
137 enum cgroup_bpf_attach_type atype);
138
139int __cgroup_bpf_run_filter_setsockopt(struct sock *sock, int *level,
140 int *optname, char __user *optval,
141 int *optlen, char **kernel_optval);
142int __cgroup_bpf_run_filter_getsockopt(struct sock *sk, int level,
143 int optname, char __user *optval,
144 int __user *optlen, int max_optlen,
145 int retval);
146
147int __cgroup_bpf_run_filter_getsockopt_kern(struct sock *sk, int level,
148 int optname, void *optval,
149 int *optlen, int retval);
150
151static inline enum bpf_cgroup_storage_type cgroup_storage_type(
152 struct bpf_map *map)
153{
154 if (map->map_type == BPF_MAP_TYPE_PERCPU_CGROUP_STORAGE)
155 return BPF_CGROUP_STORAGE_PERCPU;
156
157 return BPF_CGROUP_STORAGE_SHARED;
158}
159
160struct bpf_cgroup_storage *
161cgroup_storage_lookup(struct bpf_cgroup_storage_map *map,
162 void *key, bool locked);
163struct bpf_cgroup_storage *bpf_cgroup_storage_alloc(struct bpf_prog *prog,
164 enum bpf_cgroup_storage_type stype);
165void bpf_cgroup_storage_free(struct bpf_cgroup_storage *storage);
166void bpf_cgroup_storage_link(struct bpf_cgroup_storage *storage,
167 struct cgroup *cgroup,
168 enum bpf_attach_type type);
169void bpf_cgroup_storage_unlink(struct bpf_cgroup_storage *storage);
170int bpf_cgroup_storage_assign(struct bpf_prog_aux *aux, struct bpf_map *map);
171
172int bpf_percpu_cgroup_storage_copy(struct bpf_map *map, void *key, void *value);
173int bpf_percpu_cgroup_storage_update(struct bpf_map *map, void *key,
174 void *value, u64 flags);
175
176/* Opportunistic check to see whether we have any BPF program attached*/
177static inline bool cgroup_bpf_sock_enabled(struct sock *sk,
178 enum cgroup_bpf_attach_type type)
179{
180 struct cgroup *cgrp = sock_cgroup_ptr(&sk->sk_cgrp_data);
181 struct bpf_prog_array *array;
182
183 array = rcu_access_pointer(cgrp->bpf.effective[type]);
184 return array != &bpf_empty_prog_array.hdr;
185}
186
187/* Wrappers for __cgroup_bpf_run_filter_skb() guarded by cgroup_bpf_enabled. */
188#define BPF_CGROUP_RUN_PROG_INET_INGRESS(sk, skb) \
189({ \
190 int __ret = 0; \
191 if (cgroup_bpf_enabled(CGROUP_INET_INGRESS) && \
192 cgroup_bpf_sock_enabled(sk, CGROUP_INET_INGRESS)) \
193 __ret = __cgroup_bpf_run_filter_skb(sk, skb, \
194 CGROUP_INET_INGRESS); \
195 \
196 __ret; \
197})
198
199#define BPF_CGROUP_RUN_PROG_INET_EGRESS(sk, skb) \
200({ \
201 int __ret = 0; \
202 if (cgroup_bpf_enabled(CGROUP_INET_EGRESS) && sk && sk == skb->sk) { \
203 typeof(sk) __sk = sk_to_full_sk(sk); \
204 if (sk_fullsock(__sk) && \
205 cgroup_bpf_sock_enabled(__sk, CGROUP_INET_EGRESS)) \
206 __ret = __cgroup_bpf_run_filter_skb(__sk, skb, \
207 CGROUP_INET_EGRESS); \
208 } \
209 __ret; \
210})
211
212#define BPF_CGROUP_RUN_SK_PROG(sk, atype) \
213({ \
214 int __ret = 0; \
215 if (cgroup_bpf_enabled(atype)) { \
216 __ret = __cgroup_bpf_run_filter_sk(sk, atype); \
217 } \
218 __ret; \
219})
220
221#define BPF_CGROUP_RUN_PROG_INET_SOCK(sk) \
222 BPF_CGROUP_RUN_SK_PROG(sk, CGROUP_INET_SOCK_CREATE)
223
224#define BPF_CGROUP_RUN_PROG_INET_SOCK_RELEASE(sk) \
225 BPF_CGROUP_RUN_SK_PROG(sk, CGROUP_INET_SOCK_RELEASE)
226
227#define BPF_CGROUP_RUN_PROG_INET4_POST_BIND(sk) \
228 BPF_CGROUP_RUN_SK_PROG(sk, CGROUP_INET4_POST_BIND)
229
230#define BPF_CGROUP_RUN_PROG_INET6_POST_BIND(sk) \
231 BPF_CGROUP_RUN_SK_PROG(sk, CGROUP_INET6_POST_BIND)
232
233#define BPF_CGROUP_RUN_SA_PROG(sk, uaddr, atype) \
234({ \
235 int __ret = 0; \
236 if (cgroup_bpf_enabled(atype)) \
237 __ret = __cgroup_bpf_run_filter_sock_addr(sk, uaddr, atype, \
238 NULL, NULL); \
239 __ret; \
240})
241
242#define BPF_CGROUP_RUN_SA_PROG_LOCK(sk, uaddr, atype, t_ctx) \
243({ \
244 int __ret = 0; \
245 if (cgroup_bpf_enabled(atype)) { \
246 lock_sock(sk); \
247 __ret = __cgroup_bpf_run_filter_sock_addr(sk, uaddr, atype, \
248 t_ctx, NULL); \
249 release_sock(sk); \
250 } \
251 __ret; \
252})
253
254/* BPF_CGROUP_INET4_BIND and BPF_CGROUP_INET6_BIND can return extra flags
255 * via upper bits of return code. The only flag that is supported
256 * (at bit position 0) is to indicate CAP_NET_BIND_SERVICE capability check
257 * should be bypassed (BPF_RET_BIND_NO_CAP_NET_BIND_SERVICE).
258 */
259#define BPF_CGROUP_RUN_PROG_INET_BIND_LOCK(sk, uaddr, atype, bind_flags) \
260({ \
261 u32 __flags = 0; \
262 int __ret = 0; \
263 if (cgroup_bpf_enabled(atype)) { \
264 lock_sock(sk); \
265 __ret = __cgroup_bpf_run_filter_sock_addr(sk, uaddr, atype, \
266 NULL, &__flags); \
267 release_sock(sk); \
268 if (__flags & BPF_RET_BIND_NO_CAP_NET_BIND_SERVICE) \
269 *bind_flags |= BIND_NO_CAP_NET_BIND_SERVICE; \
270 } \
271 __ret; \
272})
273
274#define BPF_CGROUP_PRE_CONNECT_ENABLED(sk) \
275 ((cgroup_bpf_enabled(CGROUP_INET4_CONNECT) || \
276 cgroup_bpf_enabled(CGROUP_INET6_CONNECT)) && \
277 (sk)->sk_prot->pre_connect)
278
279#define BPF_CGROUP_RUN_PROG_INET4_CONNECT(sk, uaddr) \
280 BPF_CGROUP_RUN_SA_PROG(sk, uaddr, CGROUP_INET4_CONNECT)
281
282#define BPF_CGROUP_RUN_PROG_INET6_CONNECT(sk, uaddr) \
283 BPF_CGROUP_RUN_SA_PROG(sk, uaddr, CGROUP_INET6_CONNECT)
284
285#define BPF_CGROUP_RUN_PROG_INET4_CONNECT_LOCK(sk, uaddr) \
286 BPF_CGROUP_RUN_SA_PROG_LOCK(sk, uaddr, CGROUP_INET4_CONNECT, NULL)
287
288#define BPF_CGROUP_RUN_PROG_INET6_CONNECT_LOCK(sk, uaddr) \
289 BPF_CGROUP_RUN_SA_PROG_LOCK(sk, uaddr, CGROUP_INET6_CONNECT, NULL)
290
291#define BPF_CGROUP_RUN_PROG_UDP4_SENDMSG_LOCK(sk, uaddr, t_ctx) \
292 BPF_CGROUP_RUN_SA_PROG_LOCK(sk, uaddr, CGROUP_UDP4_SENDMSG, t_ctx)
293
294#define BPF_CGROUP_RUN_PROG_UDP6_SENDMSG_LOCK(sk, uaddr, t_ctx) \
295 BPF_CGROUP_RUN_SA_PROG_LOCK(sk, uaddr, CGROUP_UDP6_SENDMSG, t_ctx)
296
297#define BPF_CGROUP_RUN_PROG_UDP4_RECVMSG_LOCK(sk, uaddr) \
298 BPF_CGROUP_RUN_SA_PROG_LOCK(sk, uaddr, CGROUP_UDP4_RECVMSG, NULL)
299
300#define BPF_CGROUP_RUN_PROG_UDP6_RECVMSG_LOCK(sk, uaddr) \
301 BPF_CGROUP_RUN_SA_PROG_LOCK(sk, uaddr, CGROUP_UDP6_RECVMSG, NULL)
302
303/* The SOCK_OPS"_SK" macro should be used when sock_ops->sk is not a
304 * fullsock and its parent fullsock cannot be traced by
305 * sk_to_full_sk().
306 *
307 * e.g. sock_ops->sk is a request_sock and it is under syncookie mode.
308 * Its listener-sk is not attached to the rsk_listener.
309 * In this case, the caller holds the listener-sk (unlocked),
310 * set its sock_ops->sk to req_sk, and call this SOCK_OPS"_SK" with
311 * the listener-sk such that the cgroup-bpf-progs of the
312 * listener-sk will be run.
313 *
314 * Regardless of syncookie mode or not,
315 * calling bpf_setsockopt on listener-sk will not make sense anyway,
316 * so passing 'sock_ops->sk == req_sk' to the bpf prog is appropriate here.
317 */
318#define BPF_CGROUP_RUN_PROG_SOCK_OPS_SK(sock_ops, sk) \
319({ \
320 int __ret = 0; \
321 if (cgroup_bpf_enabled(CGROUP_SOCK_OPS)) \
322 __ret = __cgroup_bpf_run_filter_sock_ops(sk, \
323 sock_ops, \
324 CGROUP_SOCK_OPS); \
325 __ret; \
326})
327
328#define BPF_CGROUP_RUN_PROG_SOCK_OPS(sock_ops) \
329({ \
330 int __ret = 0; \
331 if (cgroup_bpf_enabled(CGROUP_SOCK_OPS) && (sock_ops)->sk) { \
332 typeof(sk) __sk = sk_to_full_sk((sock_ops)->sk); \
333 if (__sk && sk_fullsock(__sk)) \
334 __ret = __cgroup_bpf_run_filter_sock_ops(__sk, \
335 sock_ops, \
336 CGROUP_SOCK_OPS); \
337 } \
338 __ret; \
339})
340
341#define BPF_CGROUP_RUN_PROG_DEVICE_CGROUP(atype, major, minor, access) \
342({ \
343 int __ret = 0; \
344 if (cgroup_bpf_enabled(CGROUP_DEVICE)) \
345 __ret = __cgroup_bpf_check_dev_permission(atype, major, minor, \
346 access, \
347 CGROUP_DEVICE); \
348 \
349 __ret; \
350})
351
352
353#define BPF_CGROUP_RUN_PROG_SYSCTL(head, table, write, buf, count, pos) \
354({ \
355 int __ret = 0; \
356 if (cgroup_bpf_enabled(CGROUP_SYSCTL)) \
357 __ret = __cgroup_bpf_run_filter_sysctl(head, table, write, \
358 buf, count, pos, \
359 CGROUP_SYSCTL); \
360 __ret; \
361})
362
363#define BPF_CGROUP_RUN_PROG_SETSOCKOPT(sock, level, optname, optval, optlen, \
364 kernel_optval) \
365({ \
366 int __ret = 0; \
367 if (cgroup_bpf_enabled(CGROUP_SETSOCKOPT) && \
368 cgroup_bpf_sock_enabled(sock, CGROUP_SETSOCKOPT)) \
369 __ret = __cgroup_bpf_run_filter_setsockopt(sock, level, \
370 optname, optval, \
371 optlen, \
372 kernel_optval); \
373 __ret; \
374})
375
376#define BPF_CGROUP_GETSOCKOPT_MAX_OPTLEN(optlen) \
377({ \
378 int __ret = 0; \
379 if (cgroup_bpf_enabled(CGROUP_GETSOCKOPT)) \
380 get_user(__ret, optlen); \
381 __ret; \
382})
383
384#define BPF_CGROUP_RUN_PROG_GETSOCKOPT(sock, level, optname, optval, optlen, \
385 max_optlen, retval) \
386({ \
387 int __ret = retval; \
388 if (cgroup_bpf_enabled(CGROUP_GETSOCKOPT) && \
389 cgroup_bpf_sock_enabled(sock, CGROUP_GETSOCKOPT)) \
390 if (!(sock)->sk_prot->bpf_bypass_getsockopt || \
391 !INDIRECT_CALL_INET_1((sock)->sk_prot->bpf_bypass_getsockopt, \
392 tcp_bpf_bypass_getsockopt, \
393 level, optname)) \
394 __ret = __cgroup_bpf_run_filter_getsockopt( \
395 sock, level, optname, optval, optlen, \
396 max_optlen, retval); \
397 __ret; \
398})
399
400#define BPF_CGROUP_RUN_PROG_GETSOCKOPT_KERN(sock, level, optname, optval, \
401 optlen, retval) \
402({ \
403 int __ret = retval; \
404 if (cgroup_bpf_enabled(CGROUP_GETSOCKOPT)) \
405 __ret = __cgroup_bpf_run_filter_getsockopt_kern( \
406 sock, level, optname, optval, optlen, retval); \
407 __ret; \
408})
409
410int cgroup_bpf_prog_attach(const union bpf_attr *attr,
411 enum bpf_prog_type ptype, struct bpf_prog *prog);
412int cgroup_bpf_prog_detach(const union bpf_attr *attr,
413 enum bpf_prog_type ptype);
414int cgroup_bpf_link_attach(const union bpf_attr *attr, struct bpf_prog *prog);
415int cgroup_bpf_prog_query(const union bpf_attr *attr,
416 union bpf_attr __user *uattr);
417#else
418
419static inline int cgroup_bpf_inherit(struct cgroup *cgrp) { return 0; }
420static inline void cgroup_bpf_offline(struct cgroup *cgrp) {}
421
422static inline int cgroup_bpf_prog_attach(const union bpf_attr *attr,
423 enum bpf_prog_type ptype,
424 struct bpf_prog *prog)
425{
426 return -EINVAL;
427}
428
429static inline int cgroup_bpf_prog_detach(const union bpf_attr *attr,
430 enum bpf_prog_type ptype)
431{
432 return -EINVAL;
433}
434
435static inline int cgroup_bpf_link_attach(const union bpf_attr *attr,
436 struct bpf_prog *prog)
437{
438 return -EINVAL;
439}
440
441static inline int cgroup_bpf_prog_query(const union bpf_attr *attr,
442 union bpf_attr __user *uattr)
443{
444 return -EINVAL;
445}
446
447static inline int bpf_cgroup_storage_assign(struct bpf_prog_aux *aux,
448 struct bpf_map *map) { return 0; }
449static inline struct bpf_cgroup_storage *bpf_cgroup_storage_alloc(
450 struct bpf_prog *prog, enum bpf_cgroup_storage_type stype) { return NULL; }
451static inline void bpf_cgroup_storage_free(
452 struct bpf_cgroup_storage *storage) {}
453static inline int bpf_percpu_cgroup_storage_copy(struct bpf_map *map, void *key,
454 void *value) {
455 return 0;
456}
457static inline int bpf_percpu_cgroup_storage_update(struct bpf_map *map,
458 void *key, void *value, u64 flags) {
459 return 0;
460}
461
462#define cgroup_bpf_enabled(atype) (0)
463#define BPF_CGROUP_RUN_SA_PROG_LOCK(sk, uaddr, atype, t_ctx) ({ 0; })
464#define BPF_CGROUP_RUN_SA_PROG(sk, uaddr, atype) ({ 0; })
465#define BPF_CGROUP_PRE_CONNECT_ENABLED(sk) (0)
466#define BPF_CGROUP_RUN_PROG_INET_INGRESS(sk,skb) ({ 0; })
467#define BPF_CGROUP_RUN_PROG_INET_EGRESS(sk,skb) ({ 0; })
468#define BPF_CGROUP_RUN_PROG_INET_SOCK(sk) ({ 0; })
469#define BPF_CGROUP_RUN_PROG_INET_SOCK_RELEASE(sk) ({ 0; })
470#define BPF_CGROUP_RUN_PROG_INET_BIND_LOCK(sk, uaddr, atype, flags) ({ 0; })
471#define BPF_CGROUP_RUN_PROG_INET4_POST_BIND(sk) ({ 0; })
472#define BPF_CGROUP_RUN_PROG_INET6_POST_BIND(sk) ({ 0; })
473#define BPF_CGROUP_RUN_PROG_INET4_CONNECT(sk, uaddr) ({ 0; })
474#define BPF_CGROUP_RUN_PROG_INET4_CONNECT_LOCK(sk, uaddr) ({ 0; })
475#define BPF_CGROUP_RUN_PROG_INET6_CONNECT(sk, uaddr) ({ 0; })
476#define BPF_CGROUP_RUN_PROG_INET6_CONNECT_LOCK(sk, uaddr) ({ 0; })
477#define BPF_CGROUP_RUN_PROG_UDP4_SENDMSG_LOCK(sk, uaddr, t_ctx) ({ 0; })
478#define BPF_CGROUP_RUN_PROG_UDP6_SENDMSG_LOCK(sk, uaddr, t_ctx) ({ 0; })
479#define BPF_CGROUP_RUN_PROG_UDP4_RECVMSG_LOCK(sk, uaddr) ({ 0; })
480#define BPF_CGROUP_RUN_PROG_UDP6_RECVMSG_LOCK(sk, uaddr) ({ 0; })
481#define BPF_CGROUP_RUN_PROG_SOCK_OPS(sock_ops) ({ 0; })
482#define BPF_CGROUP_RUN_PROG_DEVICE_CGROUP(atype, major, minor, access) ({ 0; })
483#define BPF_CGROUP_RUN_PROG_SYSCTL(head,table,write,buf,count,pos) ({ 0; })
484#define BPF_CGROUP_GETSOCKOPT_MAX_OPTLEN(optlen) ({ 0; })
485#define BPF_CGROUP_RUN_PROG_GETSOCKOPT(sock, level, optname, optval, \
486 optlen, max_optlen, retval) ({ retval; })
487#define BPF_CGROUP_RUN_PROG_GETSOCKOPT_KERN(sock, level, optname, optval, \
488 optlen, retval) ({ retval; })
489#define BPF_CGROUP_RUN_PROG_SETSOCKOPT(sock, level, optname, optval, optlen, \
490 kernel_optval) ({ 0; })
491
492#define for_each_cgroup_storage_type(stype) for (; false; )
493
494#endif /* CONFIG_CGROUP_BPF */
495
496#endif /* _BPF_CGROUP_H */
497

source code of linux/include/linux/bpf-cgroup.h