v4.19.13 snapshot.
diff --git a/kernel/bpf/cgroup.c b/kernel/bpf/cgroup.c
new file mode 100644
index 0000000..6a7d931
--- /dev/null
+++ b/kernel/bpf/cgroup.c
@@ -0,0 +1,724 @@
+/*
+ * Functions to manage eBPF programs attached to cgroups
+ *
+ * Copyright (c) 2016 Daniel Mack
+ *
+ * This file is subject to the terms and conditions of version 2 of the GNU
+ * General Public License. See the file COPYING in the main directory of the
+ * Linux distribution for more details.
+ */
+
+#include <linux/kernel.h>
+#include <linux/atomic.h>
+#include <linux/cgroup.h>
+#include <linux/slab.h>
+#include <linux/bpf.h>
+#include <linux/bpf-cgroup.h>
+#include <net/sock.h>
+
+DEFINE_STATIC_KEY_FALSE(cgroup_bpf_enabled_key);
+EXPORT_SYMBOL(cgroup_bpf_enabled_key);
+
+/**
+ * cgroup_bpf_put() - put references of all bpf programs
+ * @cgrp: the cgroup to modify
+ */
+void cgroup_bpf_put(struct cgroup *cgrp)
+{
+ unsigned int type;
+
+ for (type = 0; type < ARRAY_SIZE(cgrp->bpf.progs); type++) {
+ struct list_head *progs = &cgrp->bpf.progs[type];
+ struct bpf_prog_list *pl, *tmp;
+
+ list_for_each_entry_safe(pl, tmp, progs, node) {
+ list_del(&pl->node);
+ bpf_prog_put(pl->prog);
+ bpf_cgroup_storage_unlink(pl->storage);
+ bpf_cgroup_storage_free(pl->storage);
+ kfree(pl);
+ static_branch_dec(&cgroup_bpf_enabled_key);
+ }
+ bpf_prog_array_free(cgrp->bpf.effective[type]);
+ }
+}
+
+/* count number of elements in the list.
+ * it's slow but the list cannot be long
+ */
+static u32 prog_list_length(struct list_head *head)
+{
+ struct bpf_prog_list *pl;
+ u32 cnt = 0;
+
+ list_for_each_entry(pl, head, node) {
+ if (!pl->prog)
+ continue;
+ cnt++;
+ }
+ return cnt;
+}
+
+/* if parent has non-overridable prog attached,
+ * disallow attaching new programs to the descendent cgroup.
+ * if parent has overridable or multi-prog, allow attaching
+ */
+static bool hierarchy_allows_attach(struct cgroup *cgrp,
+ enum bpf_attach_type type,
+ u32 new_flags)
+{
+ struct cgroup *p;
+
+ p = cgroup_parent(cgrp);
+ if (!p)
+ return true;
+ do {
+ u32 flags = p->bpf.flags[type];
+ u32 cnt;
+
+ if (flags & BPF_F_ALLOW_MULTI)
+ return true;
+ cnt = prog_list_length(&p->bpf.progs[type]);
+ WARN_ON_ONCE(cnt > 1);
+ if (cnt == 1)
+ return !!(flags & BPF_F_ALLOW_OVERRIDE);
+ p = cgroup_parent(p);
+ } while (p);
+ return true;
+}
+
+/* compute a chain of effective programs for a given cgroup:
+ * start from the list of programs in this cgroup and add
+ * all parent programs.
+ * Note that parent's F_ALLOW_OVERRIDE-type program is yielding
+ * to programs in this cgroup
+ */
+static int compute_effective_progs(struct cgroup *cgrp,
+ enum bpf_attach_type type,
+ struct bpf_prog_array __rcu **array)
+{
+ struct bpf_prog_array *progs;
+ struct bpf_prog_list *pl;
+ struct cgroup *p = cgrp;
+ int cnt = 0;
+
+ /* count number of effective programs by walking parents */
+ do {
+ if (cnt == 0 || (p->bpf.flags[type] & BPF_F_ALLOW_MULTI))
+ cnt += prog_list_length(&p->bpf.progs[type]);
+ p = cgroup_parent(p);
+ } while (p);
+
+ progs = bpf_prog_array_alloc(cnt, GFP_KERNEL);
+ if (!progs)
+ return -ENOMEM;
+
+ /* populate the array with effective progs */
+ cnt = 0;
+ p = cgrp;
+ do {
+ if (cnt > 0 && !(p->bpf.flags[type] & BPF_F_ALLOW_MULTI))
+ continue;
+
+ list_for_each_entry(pl, &p->bpf.progs[type], node) {
+ if (!pl->prog)
+ continue;
+
+ progs->items[cnt].prog = pl->prog;
+ progs->items[cnt].cgroup_storage = pl->storage;
+ cnt++;
+ }
+ } while ((p = cgroup_parent(p)));
+
+ rcu_assign_pointer(*array, progs);
+ return 0;
+}
+
+static void activate_effective_progs(struct cgroup *cgrp,
+ enum bpf_attach_type type,
+ struct bpf_prog_array __rcu *array)
+{
+ struct bpf_prog_array __rcu *old_array;
+
+ old_array = xchg(&cgrp->bpf.effective[type], array);
+ /* free prog array after grace period, since __cgroup_bpf_run_*()
+ * might be still walking the array
+ */
+ bpf_prog_array_free(old_array);
+}
+
+/**
+ * cgroup_bpf_inherit() - inherit effective programs from parent
+ * @cgrp: the cgroup to modify
+ */
+int cgroup_bpf_inherit(struct cgroup *cgrp)
+{
+/* has to use marco instead of const int, since compiler thinks
+ * that array below is variable length
+ */
+#define NR ARRAY_SIZE(cgrp->bpf.effective)
+ struct bpf_prog_array __rcu *arrays[NR] = {};
+ int i;
+
+ for (i = 0; i < NR; i++)
+ INIT_LIST_HEAD(&cgrp->bpf.progs[i]);
+
+ for (i = 0; i < NR; i++)
+ if (compute_effective_progs(cgrp, i, &arrays[i]))
+ goto cleanup;
+
+ for (i = 0; i < NR; i++)
+ activate_effective_progs(cgrp, i, arrays[i]);
+
+ return 0;
+cleanup:
+ for (i = 0; i < NR; i++)
+ bpf_prog_array_free(arrays[i]);
+ return -ENOMEM;
+}
+
+static int update_effective_progs(struct cgroup *cgrp,
+ enum bpf_attach_type type)
+{
+ struct cgroup_subsys_state *css;
+ int err;
+
+ /* allocate and recompute effective prog arrays */
+ css_for_each_descendant_pre(css, &cgrp->self) {
+ struct cgroup *desc = container_of(css, struct cgroup, self);
+
+ err = compute_effective_progs(desc, type, &desc->bpf.inactive);
+ if (err)
+ goto cleanup;
+ }
+
+ /* all allocations were successful. Activate all prog arrays */
+ css_for_each_descendant_pre(css, &cgrp->self) {
+ struct cgroup *desc = container_of(css, struct cgroup, self);
+
+ activate_effective_progs(desc, type, desc->bpf.inactive);
+ desc->bpf.inactive = NULL;
+ }
+
+ return 0;
+
+cleanup:
+ /* oom while computing effective. Free all computed effective arrays
+ * since they were not activated
+ */
+ css_for_each_descendant_pre(css, &cgrp->self) {
+ struct cgroup *desc = container_of(css, struct cgroup, self);
+
+ bpf_prog_array_free(desc->bpf.inactive);
+ desc->bpf.inactive = NULL;
+ }
+
+ return err;
+}
+
+#define BPF_CGROUP_MAX_PROGS 64
+
+/**
+ * __cgroup_bpf_attach() - Attach the program to a cgroup, and
+ * propagate the change to descendants
+ * @cgrp: The cgroup which descendants to traverse
+ * @prog: A program to attach
+ * @type: Type of attach operation
+ *
+ * Must be called with cgroup_mutex held.
+ */
+int __cgroup_bpf_attach(struct cgroup *cgrp, struct bpf_prog *prog,
+ enum bpf_attach_type type, u32 flags)
+{
+ struct list_head *progs = &cgrp->bpf.progs[type];
+ struct bpf_prog *old_prog = NULL;
+ struct bpf_cgroup_storage *storage, *old_storage = NULL;
+ struct bpf_prog_list *pl;
+ bool pl_was_allocated;
+ int err;
+
+ if ((flags & BPF_F_ALLOW_OVERRIDE) && (flags & BPF_F_ALLOW_MULTI))
+ /* invalid combination */
+ return -EINVAL;
+
+ if (!hierarchy_allows_attach(cgrp, type, flags))
+ return -EPERM;
+
+ if (!list_empty(progs) && cgrp->bpf.flags[type] != flags)
+ /* Disallow attaching non-overridable on top
+ * of existing overridable in this cgroup.
+ * Disallow attaching multi-prog if overridable or none
+ */
+ return -EPERM;
+
+ if (prog_list_length(progs) >= BPF_CGROUP_MAX_PROGS)
+ return -E2BIG;
+
+ storage = bpf_cgroup_storage_alloc(prog);
+ if (IS_ERR(storage))
+ return -ENOMEM;
+
+ if (flags & BPF_F_ALLOW_MULTI) {
+ list_for_each_entry(pl, progs, node) {
+ if (pl->prog == prog) {
+ /* disallow attaching the same prog twice */
+ bpf_cgroup_storage_free(storage);
+ return -EINVAL;
+ }
+ }
+
+ pl = kmalloc(sizeof(*pl), GFP_KERNEL);
+ if (!pl) {
+ bpf_cgroup_storage_free(storage);
+ return -ENOMEM;
+ }
+
+ pl_was_allocated = true;
+ pl->prog = prog;
+ pl->storage = storage;
+ list_add_tail(&pl->node, progs);
+ } else {
+ if (list_empty(progs)) {
+ pl = kmalloc(sizeof(*pl), GFP_KERNEL);
+ if (!pl) {
+ bpf_cgroup_storage_free(storage);
+ return -ENOMEM;
+ }
+ pl_was_allocated = true;
+ list_add_tail(&pl->node, progs);
+ } else {
+ pl = list_first_entry(progs, typeof(*pl), node);
+ old_prog = pl->prog;
+ old_storage = pl->storage;
+ bpf_cgroup_storage_unlink(old_storage);
+ pl_was_allocated = false;
+ }
+ pl->prog = prog;
+ pl->storage = storage;
+ }
+
+ cgrp->bpf.flags[type] = flags;
+
+ err = update_effective_progs(cgrp, type);
+ if (err)
+ goto cleanup;
+
+ static_branch_inc(&cgroup_bpf_enabled_key);
+ if (old_storage)
+ bpf_cgroup_storage_free(old_storage);
+ if (old_prog) {
+ bpf_prog_put(old_prog);
+ static_branch_dec(&cgroup_bpf_enabled_key);
+ }
+ bpf_cgroup_storage_link(storage, cgrp, type);
+ return 0;
+
+cleanup:
+ /* and cleanup the prog list */
+ pl->prog = old_prog;
+ bpf_cgroup_storage_free(pl->storage);
+ pl->storage = old_storage;
+ bpf_cgroup_storage_link(old_storage, cgrp, type);
+ if (pl_was_allocated) {
+ list_del(&pl->node);
+ kfree(pl);
+ }
+ return err;
+}
+
+/**
+ * __cgroup_bpf_detach() - Detach the program from a cgroup, and
+ * propagate the change to descendants
+ * @cgrp: The cgroup which descendants to traverse
+ * @prog: A program to detach or NULL
+ * @type: Type of detach operation
+ *
+ * Must be called with cgroup_mutex held.
+ */
+int __cgroup_bpf_detach(struct cgroup *cgrp, struct bpf_prog *prog,
+ enum bpf_attach_type type, u32 unused_flags)
+{
+ struct list_head *progs = &cgrp->bpf.progs[type];
+ u32 flags = cgrp->bpf.flags[type];
+ struct bpf_prog *old_prog = NULL;
+ struct bpf_prog_list *pl;
+ int err;
+
+ if (flags & BPF_F_ALLOW_MULTI) {
+ if (!prog)
+ /* to detach MULTI prog the user has to specify valid FD
+ * of the program to be detached
+ */
+ return -EINVAL;
+ } else {
+ if (list_empty(progs))
+ /* report error when trying to detach and nothing is attached */
+ return -ENOENT;
+ }
+
+ if (flags & BPF_F_ALLOW_MULTI) {
+ /* find the prog and detach it */
+ list_for_each_entry(pl, progs, node) {
+ if (pl->prog != prog)
+ continue;
+ old_prog = prog;
+ /* mark it deleted, so it's ignored while
+ * recomputing effective
+ */
+ pl->prog = NULL;
+ break;
+ }
+ if (!old_prog)
+ return -ENOENT;
+ } else {
+ /* to maintain backward compatibility NONE and OVERRIDE cgroups
+ * allow detaching with invalid FD (prog==NULL)
+ */
+ pl = list_first_entry(progs, typeof(*pl), node);
+ old_prog = pl->prog;
+ pl->prog = NULL;
+ }
+
+ err = update_effective_progs(cgrp, type);
+ if (err)
+ goto cleanup;
+
+ /* now can actually delete it from this cgroup list */
+ list_del(&pl->node);
+ bpf_cgroup_storage_unlink(pl->storage);
+ bpf_cgroup_storage_free(pl->storage);
+ kfree(pl);
+ if (list_empty(progs))
+ /* last program was detached, reset flags to zero */
+ cgrp->bpf.flags[type] = 0;
+
+ bpf_prog_put(old_prog);
+ static_branch_dec(&cgroup_bpf_enabled_key);
+ return 0;
+
+cleanup:
+ /* and restore back old_prog */
+ pl->prog = old_prog;
+ return err;
+}
+
+/* Must be called with cgroup_mutex held to avoid races. */
+int __cgroup_bpf_query(struct cgroup *cgrp, const union bpf_attr *attr,
+ union bpf_attr __user *uattr)
+{
+ __u32 __user *prog_ids = u64_to_user_ptr(attr->query.prog_ids);
+ enum bpf_attach_type type = attr->query.attach_type;
+ struct list_head *progs = &cgrp->bpf.progs[type];
+ u32 flags = cgrp->bpf.flags[type];
+ int cnt, ret = 0, i;
+
+ if (attr->query.query_flags & BPF_F_QUERY_EFFECTIVE)
+ cnt = bpf_prog_array_length(cgrp->bpf.effective[type]);
+ else
+ cnt = prog_list_length(progs);
+
+ if (copy_to_user(&uattr->query.attach_flags, &flags, sizeof(flags)))
+ return -EFAULT;
+ if (copy_to_user(&uattr->query.prog_cnt, &cnt, sizeof(cnt)))
+ return -EFAULT;
+ if (attr->query.prog_cnt == 0 || !prog_ids || !cnt)
+ /* return early if user requested only program count + flags */
+ return 0;
+ if (attr->query.prog_cnt < cnt) {
+ cnt = attr->query.prog_cnt;
+ ret = -ENOSPC;
+ }
+
+ if (attr->query.query_flags & BPF_F_QUERY_EFFECTIVE) {
+ return bpf_prog_array_copy_to_user(cgrp->bpf.effective[type],
+ prog_ids, cnt);
+ } else {
+ struct bpf_prog_list *pl;
+ u32 id;
+
+ i = 0;
+ list_for_each_entry(pl, progs, node) {
+ id = pl->prog->aux->id;
+ if (copy_to_user(prog_ids + i, &id, sizeof(id)))
+ return -EFAULT;
+ if (++i == cnt)
+ break;
+ }
+ }
+ return ret;
+}
+
+int cgroup_bpf_prog_attach(const union bpf_attr *attr,
+ enum bpf_prog_type ptype, struct bpf_prog *prog)
+{
+ struct cgroup *cgrp;
+ int ret;
+
+ cgrp = cgroup_get_from_fd(attr->target_fd);
+ if (IS_ERR(cgrp))
+ return PTR_ERR(cgrp);
+
+ ret = cgroup_bpf_attach(cgrp, prog, attr->attach_type,
+ attr->attach_flags);
+ cgroup_put(cgrp);
+ return ret;
+}
+
+int cgroup_bpf_prog_detach(const union bpf_attr *attr, enum bpf_prog_type ptype)
+{
+ struct bpf_prog *prog;
+ struct cgroup *cgrp;
+ int ret;
+
+ cgrp = cgroup_get_from_fd(attr->target_fd);
+ if (IS_ERR(cgrp))
+ return PTR_ERR(cgrp);
+
+ prog = bpf_prog_get_type(attr->attach_bpf_fd, ptype);
+ if (IS_ERR(prog))
+ prog = NULL;
+
+ ret = cgroup_bpf_detach(cgrp, prog, attr->attach_type, 0);
+ if (prog)
+ bpf_prog_put(prog);
+
+ cgroup_put(cgrp);
+ return ret;
+}
+
+int cgroup_bpf_prog_query(const union bpf_attr *attr,
+ union bpf_attr __user *uattr)
+{
+ struct cgroup *cgrp;
+ int ret;
+
+ cgrp = cgroup_get_from_fd(attr->query.target_fd);
+ if (IS_ERR(cgrp))
+ return PTR_ERR(cgrp);
+
+ ret = cgroup_bpf_query(cgrp, attr, uattr);
+
+ cgroup_put(cgrp);
+ return ret;
+}
+
+/**
+ * __cgroup_bpf_run_filter_skb() - Run a program for packet filtering
+ * @sk: The socket sending or receiving traffic
+ * @skb: The skb that is being sent or received
+ * @type: The type of program to be exectuted
+ *
+ * If no socket is passed, or the socket is not of type INET or INET6,
+ * this function does nothing and returns 0.
+ *
+ * The program type passed in via @type must be suitable for network
+ * filtering. No further check is performed to assert that.
+ *
+ * This function will return %-EPERM if any if an attached program was found
+ * and if it returned != 1 during execution. In all other cases, 0 is returned.
+ */
+int __cgroup_bpf_run_filter_skb(struct sock *sk,
+ struct sk_buff *skb,
+ enum bpf_attach_type type)
+{
+ unsigned int offset = skb->data - skb_network_header(skb);
+ struct sock *save_sk;
+ struct cgroup *cgrp;
+ int ret;
+
+ if (!sk || !sk_fullsock(sk))
+ return 0;
+
+ if (sk->sk_family != AF_INET && sk->sk_family != AF_INET6)
+ return 0;
+
+ cgrp = sock_cgroup_ptr(&sk->sk_cgrp_data);
+ save_sk = skb->sk;
+ skb->sk = sk;
+ __skb_push(skb, offset);
+ ret = BPF_PROG_RUN_ARRAY(cgrp->bpf.effective[type], skb,
+ bpf_prog_run_save_cb);
+ __skb_pull(skb, offset);
+ skb->sk = save_sk;
+ return ret == 1 ? 0 : -EPERM;
+}
+EXPORT_SYMBOL(__cgroup_bpf_run_filter_skb);
+
+/**
+ * __cgroup_bpf_run_filter_sk() - Run a program on a sock
+ * @sk: sock structure to manipulate
+ * @type: The type of program to be exectuted
+ *
+ * socket is passed is expected to be of type INET or INET6.
+ *
+ * The program type passed in via @type must be suitable for sock
+ * filtering. No further check is performed to assert that.
+ *
+ * This function will return %-EPERM if any if an attached program was found
+ * and if it returned != 1 during execution. In all other cases, 0 is returned.
+ */
+int __cgroup_bpf_run_filter_sk(struct sock *sk,
+ enum bpf_attach_type type)
+{
+ struct cgroup *cgrp = sock_cgroup_ptr(&sk->sk_cgrp_data);
+ int ret;
+
+ ret = BPF_PROG_RUN_ARRAY(cgrp->bpf.effective[type], sk, BPF_PROG_RUN);
+ return ret == 1 ? 0 : -EPERM;
+}
+EXPORT_SYMBOL(__cgroup_bpf_run_filter_sk);
+
+/**
+ * __cgroup_bpf_run_filter_sock_addr() - Run a program on a sock and
+ * provided by user sockaddr
+ * @sk: sock struct that will use sockaddr
+ * @uaddr: sockaddr struct provided by user
+ * @type: The type of program to be exectuted
+ * @t_ctx: Pointer to attach type specific context
+ *
+ * socket is expected to be of type INET or INET6.
+ *
+ * This function will return %-EPERM if an attached program is found and
+ * returned value != 1 during execution. In all other cases, 0 is returned.
+ */
+int __cgroup_bpf_run_filter_sock_addr(struct sock *sk,
+ struct sockaddr *uaddr,
+ enum bpf_attach_type type,
+ void *t_ctx)
+{
+ struct bpf_sock_addr_kern ctx = {
+ .sk = sk,
+ .uaddr = uaddr,
+ .t_ctx = t_ctx,
+ };
+ struct sockaddr_storage unspec;
+ struct cgroup *cgrp;
+ int ret;
+
+ /* Check socket family since not all sockets represent network
+ * endpoint (e.g. AF_UNIX).
+ */
+ if (sk->sk_family != AF_INET && sk->sk_family != AF_INET6)
+ return 0;
+
+ if (!ctx.uaddr) {
+ memset(&unspec, 0, sizeof(unspec));
+ ctx.uaddr = (struct sockaddr *)&unspec;
+ }
+
+ cgrp = sock_cgroup_ptr(&sk->sk_cgrp_data);
+ ret = BPF_PROG_RUN_ARRAY(cgrp->bpf.effective[type], &ctx, BPF_PROG_RUN);
+
+ return ret == 1 ? 0 : -EPERM;
+}
+EXPORT_SYMBOL(__cgroup_bpf_run_filter_sock_addr);
+
+/**
+ * __cgroup_bpf_run_filter_sock_ops() - Run a program on a sock
+ * @sk: socket to get cgroup from
+ * @sock_ops: bpf_sock_ops_kern struct to pass to program. Contains
+ * sk with connection information (IP addresses, etc.) May not contain
+ * cgroup info if it is a req sock.
+ * @type: The type of program to be exectuted
+ *
+ * socket passed is expected to be of type INET or INET6.
+ *
+ * The program type passed in via @type must be suitable for sock_ops
+ * filtering. No further check is performed to assert that.
+ *
+ * This function will return %-EPERM if any if an attached program was found
+ * and if it returned != 1 during execution. In all other cases, 0 is returned.
+ */
+int __cgroup_bpf_run_filter_sock_ops(struct sock *sk,
+ struct bpf_sock_ops_kern *sock_ops,
+ enum bpf_attach_type type)
+{
+ struct cgroup *cgrp = sock_cgroup_ptr(&sk->sk_cgrp_data);
+ int ret;
+
+ ret = BPF_PROG_RUN_ARRAY(cgrp->bpf.effective[type], sock_ops,
+ BPF_PROG_RUN);
+ return ret == 1 ? 0 : -EPERM;
+}
+EXPORT_SYMBOL(__cgroup_bpf_run_filter_sock_ops);
+
+int __cgroup_bpf_check_dev_permission(short dev_type, u32 major, u32 minor,
+ short access, enum bpf_attach_type type)
+{
+ struct cgroup *cgrp;
+ struct bpf_cgroup_dev_ctx ctx = {
+ .access_type = (access << 16) | dev_type,
+ .major = major,
+ .minor = minor,
+ };
+ int allow = 1;
+
+ rcu_read_lock();
+ cgrp = task_dfl_cgroup(current);
+ allow = BPF_PROG_RUN_ARRAY(cgrp->bpf.effective[type], &ctx,
+ BPF_PROG_RUN);
+ rcu_read_unlock();
+
+ return !allow;
+}
+EXPORT_SYMBOL(__cgroup_bpf_check_dev_permission);
+
+static const struct bpf_func_proto *
+cgroup_dev_func_proto(enum bpf_func_id func_id, const struct bpf_prog *prog)
+{
+ switch (func_id) {
+ case BPF_FUNC_map_lookup_elem:
+ return &bpf_map_lookup_elem_proto;
+ case BPF_FUNC_map_update_elem:
+ return &bpf_map_update_elem_proto;
+ case BPF_FUNC_map_delete_elem:
+ return &bpf_map_delete_elem_proto;
+ case BPF_FUNC_get_current_uid_gid:
+ return &bpf_get_current_uid_gid_proto;
+ case BPF_FUNC_get_local_storage:
+ return &bpf_get_local_storage_proto;
+ case BPF_FUNC_trace_printk:
+ if (capable(CAP_SYS_ADMIN))
+ return bpf_get_trace_printk_proto();
+ default:
+ return NULL;
+ }
+}
+
+static bool cgroup_dev_is_valid_access(int off, int size,
+ enum bpf_access_type type,
+ const struct bpf_prog *prog,
+ struct bpf_insn_access_aux *info)
+{
+ const int size_default = sizeof(__u32);
+
+ if (type == BPF_WRITE)
+ return false;
+
+ if (off < 0 || off + size > sizeof(struct bpf_cgroup_dev_ctx))
+ return false;
+ /* The verifier guarantees that size > 0. */
+ if (off % size != 0)
+ return false;
+
+ switch (off) {
+ case bpf_ctx_range(struct bpf_cgroup_dev_ctx, access_type):
+ bpf_ctx_record_field_size(info, size_default);
+ if (!bpf_ctx_narrow_access_ok(off, size, size_default))
+ return false;
+ break;
+ default:
+ if (size != size_default)
+ return false;
+ }
+
+ return true;
+}
+
+const struct bpf_prog_ops cg_dev_prog_ops = {
+};
+
+const struct bpf_verifier_ops cg_dev_verifier_ops = {
+ .get_func_proto = cgroup_dev_func_proto,
+ .is_valid_access = cgroup_dev_is_valid_access,
+};