mirror of
https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-08-23 09:19:51 +00:00
![Jiang Wang](/assets/img/avatar_default.png)
Previously, sockmap for AF_UNIX protocol only supports dgram type. This patch add unix stream type support, which is similar to unix_dgram_proto. To support sockmap, dgram and stream cannot share the same unix_proto anymore, because they have different implementations, such as unhash for stream type (which will remove closed or disconnected sockets from the map), so rename unix_proto to unix_dgram_proto and add a new unix_stream_proto. Also implement stream related sockmap functions. And add dgram key words to those dgram specific functions. Signed-off-by: Jiang Wang <jiang.wang@bytedance.com> Signed-off-by: Andrii Nakryiko <andrii@kernel.org> Reviewed-by: Cong Wang <cong.wang@bytedance.com> Acked-by: Jakub Sitnicki <jakub@cloudflare.com> Acked-by: John Fastabend <john.fastabend@gmail.com> Link: https://lore.kernel.org/bpf/20210816190327.2739291-3-jiang.wang@bytedance.com
1580 lines
37 KiB
C
1580 lines
37 KiB
C
// SPDX-License-Identifier: GPL-2.0
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/* Copyright (c) 2017 - 2018 Covalent IO, Inc. http://covalent.io */
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#include <linux/bpf.h>
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#include <linux/btf_ids.h>
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#include <linux/filter.h>
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#include <linux/errno.h>
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#include <linux/file.h>
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#include <linux/net.h>
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#include <linux/workqueue.h>
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#include <linux/skmsg.h>
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#include <linux/list.h>
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#include <linux/jhash.h>
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#include <linux/sock_diag.h>
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#include <net/udp.h>
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struct bpf_stab {
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struct bpf_map map;
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struct sock **sks;
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struct sk_psock_progs progs;
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raw_spinlock_t lock;
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};
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#define SOCK_CREATE_FLAG_MASK \
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(BPF_F_NUMA_NODE | BPF_F_RDONLY | BPF_F_WRONLY)
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static int sock_map_prog_update(struct bpf_map *map, struct bpf_prog *prog,
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struct bpf_prog *old, u32 which);
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static struct sk_psock_progs *sock_map_progs(struct bpf_map *map);
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static struct bpf_map *sock_map_alloc(union bpf_attr *attr)
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{
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struct bpf_stab *stab;
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if (!capable(CAP_NET_ADMIN))
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return ERR_PTR(-EPERM);
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if (attr->max_entries == 0 ||
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attr->key_size != 4 ||
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(attr->value_size != sizeof(u32) &&
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attr->value_size != sizeof(u64)) ||
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attr->map_flags & ~SOCK_CREATE_FLAG_MASK)
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return ERR_PTR(-EINVAL);
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stab = kzalloc(sizeof(*stab), GFP_USER | __GFP_ACCOUNT);
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if (!stab)
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return ERR_PTR(-ENOMEM);
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bpf_map_init_from_attr(&stab->map, attr);
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raw_spin_lock_init(&stab->lock);
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stab->sks = bpf_map_area_alloc((u64) stab->map.max_entries *
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sizeof(struct sock *),
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stab->map.numa_node);
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if (!stab->sks) {
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kfree(stab);
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return ERR_PTR(-ENOMEM);
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}
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return &stab->map;
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}
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int sock_map_get_from_fd(const union bpf_attr *attr, struct bpf_prog *prog)
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{
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u32 ufd = attr->target_fd;
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struct bpf_map *map;
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struct fd f;
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int ret;
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if (attr->attach_flags || attr->replace_bpf_fd)
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return -EINVAL;
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f = fdget(ufd);
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map = __bpf_map_get(f);
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if (IS_ERR(map))
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return PTR_ERR(map);
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ret = sock_map_prog_update(map, prog, NULL, attr->attach_type);
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fdput(f);
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return ret;
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}
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int sock_map_prog_detach(const union bpf_attr *attr, enum bpf_prog_type ptype)
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{
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u32 ufd = attr->target_fd;
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struct bpf_prog *prog;
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struct bpf_map *map;
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struct fd f;
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int ret;
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if (attr->attach_flags || attr->replace_bpf_fd)
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return -EINVAL;
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f = fdget(ufd);
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map = __bpf_map_get(f);
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if (IS_ERR(map))
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return PTR_ERR(map);
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prog = bpf_prog_get(attr->attach_bpf_fd);
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if (IS_ERR(prog)) {
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ret = PTR_ERR(prog);
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goto put_map;
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}
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if (prog->type != ptype) {
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ret = -EINVAL;
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goto put_prog;
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}
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ret = sock_map_prog_update(map, NULL, prog, attr->attach_type);
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put_prog:
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bpf_prog_put(prog);
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put_map:
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fdput(f);
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return ret;
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}
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static void sock_map_sk_acquire(struct sock *sk)
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__acquires(&sk->sk_lock.slock)
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{
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lock_sock(sk);
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preempt_disable();
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rcu_read_lock();
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}
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static void sock_map_sk_release(struct sock *sk)
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__releases(&sk->sk_lock.slock)
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{
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rcu_read_unlock();
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preempt_enable();
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release_sock(sk);
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}
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static void sock_map_add_link(struct sk_psock *psock,
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struct sk_psock_link *link,
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struct bpf_map *map, void *link_raw)
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{
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link->link_raw = link_raw;
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link->map = map;
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spin_lock_bh(&psock->link_lock);
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list_add_tail(&link->list, &psock->link);
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spin_unlock_bh(&psock->link_lock);
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}
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static void sock_map_del_link(struct sock *sk,
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struct sk_psock *psock, void *link_raw)
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{
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bool strp_stop = false, verdict_stop = false;
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struct sk_psock_link *link, *tmp;
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spin_lock_bh(&psock->link_lock);
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list_for_each_entry_safe(link, tmp, &psock->link, list) {
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if (link->link_raw == link_raw) {
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struct bpf_map *map = link->map;
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struct bpf_stab *stab = container_of(map, struct bpf_stab,
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map);
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if (psock->saved_data_ready && stab->progs.stream_parser)
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strp_stop = true;
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if (psock->saved_data_ready && stab->progs.stream_verdict)
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verdict_stop = true;
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if (psock->saved_data_ready && stab->progs.skb_verdict)
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verdict_stop = true;
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list_del(&link->list);
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sk_psock_free_link(link);
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}
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}
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spin_unlock_bh(&psock->link_lock);
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if (strp_stop || verdict_stop) {
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write_lock_bh(&sk->sk_callback_lock);
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if (strp_stop)
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sk_psock_stop_strp(sk, psock);
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else
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sk_psock_stop_verdict(sk, psock);
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write_unlock_bh(&sk->sk_callback_lock);
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}
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}
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static void sock_map_unref(struct sock *sk, void *link_raw)
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{
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struct sk_psock *psock = sk_psock(sk);
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if (likely(psock)) {
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sock_map_del_link(sk, psock, link_raw);
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sk_psock_put(sk, psock);
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}
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}
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static int sock_map_init_proto(struct sock *sk, struct sk_psock *psock)
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{
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if (!sk->sk_prot->psock_update_sk_prot)
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return -EINVAL;
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psock->psock_update_sk_prot = sk->sk_prot->psock_update_sk_prot;
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return sk->sk_prot->psock_update_sk_prot(sk, psock, false);
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}
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static struct sk_psock *sock_map_psock_get_checked(struct sock *sk)
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{
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struct sk_psock *psock;
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rcu_read_lock();
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psock = sk_psock(sk);
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if (psock) {
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if (sk->sk_prot->close != sock_map_close) {
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psock = ERR_PTR(-EBUSY);
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goto out;
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}
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if (!refcount_inc_not_zero(&psock->refcnt))
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psock = ERR_PTR(-EBUSY);
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}
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out:
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rcu_read_unlock();
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return psock;
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}
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static int sock_map_link(struct bpf_map *map, struct sock *sk)
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{
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struct sk_psock_progs *progs = sock_map_progs(map);
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struct bpf_prog *stream_verdict = NULL;
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struct bpf_prog *stream_parser = NULL;
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struct bpf_prog *skb_verdict = NULL;
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struct bpf_prog *msg_parser = NULL;
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struct sk_psock *psock;
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int ret;
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stream_verdict = READ_ONCE(progs->stream_verdict);
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if (stream_verdict) {
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stream_verdict = bpf_prog_inc_not_zero(stream_verdict);
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if (IS_ERR(stream_verdict))
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return PTR_ERR(stream_verdict);
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}
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stream_parser = READ_ONCE(progs->stream_parser);
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if (stream_parser) {
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stream_parser = bpf_prog_inc_not_zero(stream_parser);
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if (IS_ERR(stream_parser)) {
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ret = PTR_ERR(stream_parser);
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goto out_put_stream_verdict;
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}
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}
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msg_parser = READ_ONCE(progs->msg_parser);
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if (msg_parser) {
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msg_parser = bpf_prog_inc_not_zero(msg_parser);
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if (IS_ERR(msg_parser)) {
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ret = PTR_ERR(msg_parser);
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goto out_put_stream_parser;
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}
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}
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skb_verdict = READ_ONCE(progs->skb_verdict);
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if (skb_verdict) {
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skb_verdict = bpf_prog_inc_not_zero(skb_verdict);
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if (IS_ERR(skb_verdict)) {
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ret = PTR_ERR(skb_verdict);
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goto out_put_msg_parser;
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}
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}
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psock = sock_map_psock_get_checked(sk);
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if (IS_ERR(psock)) {
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ret = PTR_ERR(psock);
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goto out_progs;
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}
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if (psock) {
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if ((msg_parser && READ_ONCE(psock->progs.msg_parser)) ||
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(stream_parser && READ_ONCE(psock->progs.stream_parser)) ||
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(skb_verdict && READ_ONCE(psock->progs.skb_verdict)) ||
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(skb_verdict && READ_ONCE(psock->progs.stream_verdict)) ||
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(stream_verdict && READ_ONCE(psock->progs.skb_verdict)) ||
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(stream_verdict && READ_ONCE(psock->progs.stream_verdict))) {
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sk_psock_put(sk, psock);
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ret = -EBUSY;
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goto out_progs;
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}
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} else {
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psock = sk_psock_init(sk, map->numa_node);
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if (IS_ERR(psock)) {
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ret = PTR_ERR(psock);
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goto out_progs;
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}
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}
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if (msg_parser)
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psock_set_prog(&psock->progs.msg_parser, msg_parser);
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ret = sock_map_init_proto(sk, psock);
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if (ret < 0)
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goto out_drop;
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write_lock_bh(&sk->sk_callback_lock);
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if (stream_parser && stream_verdict && !psock->saved_data_ready) {
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ret = sk_psock_init_strp(sk, psock);
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if (ret)
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goto out_unlock_drop;
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psock_set_prog(&psock->progs.stream_verdict, stream_verdict);
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psock_set_prog(&psock->progs.stream_parser, stream_parser);
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sk_psock_start_strp(sk, psock);
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} else if (!stream_parser && stream_verdict && !psock->saved_data_ready) {
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psock_set_prog(&psock->progs.stream_verdict, stream_verdict);
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sk_psock_start_verdict(sk,psock);
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} else if (!stream_verdict && skb_verdict && !psock->saved_data_ready) {
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psock_set_prog(&psock->progs.skb_verdict, skb_verdict);
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sk_psock_start_verdict(sk, psock);
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}
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write_unlock_bh(&sk->sk_callback_lock);
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return 0;
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out_unlock_drop:
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write_unlock_bh(&sk->sk_callback_lock);
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out_drop:
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sk_psock_put(sk, psock);
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out_progs:
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if (skb_verdict)
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bpf_prog_put(skb_verdict);
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out_put_msg_parser:
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if (msg_parser)
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bpf_prog_put(msg_parser);
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out_put_stream_parser:
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if (stream_parser)
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bpf_prog_put(stream_parser);
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out_put_stream_verdict:
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if (stream_verdict)
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bpf_prog_put(stream_verdict);
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return ret;
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}
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static void sock_map_free(struct bpf_map *map)
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{
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struct bpf_stab *stab = container_of(map, struct bpf_stab, map);
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int i;
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/* After the sync no updates or deletes will be in-flight so it
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* is safe to walk map and remove entries without risking a race
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* in EEXIST update case.
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*/
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synchronize_rcu();
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for (i = 0; i < stab->map.max_entries; i++) {
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struct sock **psk = &stab->sks[i];
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struct sock *sk;
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sk = xchg(psk, NULL);
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if (sk) {
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lock_sock(sk);
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rcu_read_lock();
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sock_map_unref(sk, psk);
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rcu_read_unlock();
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release_sock(sk);
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}
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}
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/* wait for psock readers accessing its map link */
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synchronize_rcu();
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bpf_map_area_free(stab->sks);
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kfree(stab);
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}
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static void sock_map_release_progs(struct bpf_map *map)
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{
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psock_progs_drop(&container_of(map, struct bpf_stab, map)->progs);
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}
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static struct sock *__sock_map_lookup_elem(struct bpf_map *map, u32 key)
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{
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struct bpf_stab *stab = container_of(map, struct bpf_stab, map);
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WARN_ON_ONCE(!rcu_read_lock_held());
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if (unlikely(key >= map->max_entries))
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return NULL;
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return READ_ONCE(stab->sks[key]);
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}
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static void *sock_map_lookup(struct bpf_map *map, void *key)
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{
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struct sock *sk;
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sk = __sock_map_lookup_elem(map, *(u32 *)key);
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if (!sk)
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return NULL;
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if (sk_is_refcounted(sk) && !refcount_inc_not_zero(&sk->sk_refcnt))
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return NULL;
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return sk;
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}
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static void *sock_map_lookup_sys(struct bpf_map *map, void *key)
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{
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struct sock *sk;
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if (map->value_size != sizeof(u64))
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return ERR_PTR(-ENOSPC);
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sk = __sock_map_lookup_elem(map, *(u32 *)key);
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if (!sk)
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return ERR_PTR(-ENOENT);
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__sock_gen_cookie(sk);
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return &sk->sk_cookie;
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}
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static int __sock_map_delete(struct bpf_stab *stab, struct sock *sk_test,
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struct sock **psk)
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{
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struct sock *sk;
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int err = 0;
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raw_spin_lock_bh(&stab->lock);
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sk = *psk;
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if (!sk_test || sk_test == sk)
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sk = xchg(psk, NULL);
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if (likely(sk))
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sock_map_unref(sk, psk);
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else
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err = -EINVAL;
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raw_spin_unlock_bh(&stab->lock);
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return err;
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}
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|
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static void sock_map_delete_from_link(struct bpf_map *map, struct sock *sk,
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void *link_raw)
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{
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struct bpf_stab *stab = container_of(map, struct bpf_stab, map);
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__sock_map_delete(stab, sk, link_raw);
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}
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static int sock_map_delete_elem(struct bpf_map *map, void *key)
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{
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struct bpf_stab *stab = container_of(map, struct bpf_stab, map);
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u32 i = *(u32 *)key;
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struct sock **psk;
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if (unlikely(i >= map->max_entries))
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return -EINVAL;
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psk = &stab->sks[i];
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return __sock_map_delete(stab, NULL, psk);
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}
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|
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static int sock_map_get_next_key(struct bpf_map *map, void *key, void *next)
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{
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struct bpf_stab *stab = container_of(map, struct bpf_stab, map);
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u32 i = key ? *(u32 *)key : U32_MAX;
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u32 *key_next = next;
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if (i == stab->map.max_entries - 1)
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return -ENOENT;
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if (i >= stab->map.max_entries)
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*key_next = 0;
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else
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*key_next = i + 1;
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return 0;
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}
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|
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static int sock_map_update_common(struct bpf_map *map, u32 idx,
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struct sock *sk, u64 flags)
|
|
{
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struct bpf_stab *stab = container_of(map, struct bpf_stab, map);
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struct sk_psock_link *link;
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struct sk_psock *psock;
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struct sock *osk;
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int ret;
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WARN_ON_ONCE(!rcu_read_lock_held());
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if (unlikely(flags > BPF_EXIST))
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return -EINVAL;
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if (unlikely(idx >= map->max_entries))
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return -E2BIG;
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|
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link = sk_psock_init_link();
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if (!link)
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return -ENOMEM;
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|
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ret = sock_map_link(map, sk);
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if (ret < 0)
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goto out_free;
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psock = sk_psock(sk);
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WARN_ON_ONCE(!psock);
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|
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raw_spin_lock_bh(&stab->lock);
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osk = stab->sks[idx];
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if (osk && flags == BPF_NOEXIST) {
|
|
ret = -EEXIST;
|
|
goto out_unlock;
|
|
} else if (!osk && flags == BPF_EXIST) {
|
|
ret = -ENOENT;
|
|
goto out_unlock;
|
|
}
|
|
|
|
sock_map_add_link(psock, link, map, &stab->sks[idx]);
|
|
stab->sks[idx] = sk;
|
|
if (osk)
|
|
sock_map_unref(osk, &stab->sks[idx]);
|
|
raw_spin_unlock_bh(&stab->lock);
|
|
return 0;
|
|
out_unlock:
|
|
raw_spin_unlock_bh(&stab->lock);
|
|
if (psock)
|
|
sk_psock_put(sk, psock);
|
|
out_free:
|
|
sk_psock_free_link(link);
|
|
return ret;
|
|
}
|
|
|
|
static bool sock_map_op_okay(const struct bpf_sock_ops_kern *ops)
|
|
{
|
|
return ops->op == BPF_SOCK_OPS_PASSIVE_ESTABLISHED_CB ||
|
|
ops->op == BPF_SOCK_OPS_ACTIVE_ESTABLISHED_CB ||
|
|
ops->op == BPF_SOCK_OPS_TCP_LISTEN_CB;
|
|
}
|
|
|
|
static bool sk_is_tcp(const struct sock *sk)
|
|
{
|
|
return sk->sk_type == SOCK_STREAM &&
|
|
sk->sk_protocol == IPPROTO_TCP;
|
|
}
|
|
|
|
static bool sock_map_redirect_allowed(const struct sock *sk)
|
|
{
|
|
if (sk_is_tcp(sk))
|
|
return sk->sk_state != TCP_LISTEN;
|
|
else
|
|
return sk->sk_state == TCP_ESTABLISHED;
|
|
}
|
|
|
|
static bool sock_map_sk_is_suitable(const struct sock *sk)
|
|
{
|
|
return !!sk->sk_prot->psock_update_sk_prot;
|
|
}
|
|
|
|
static bool sock_map_sk_state_allowed(const struct sock *sk)
|
|
{
|
|
if (sk_is_tcp(sk))
|
|
return (1 << sk->sk_state) & (TCPF_ESTABLISHED | TCPF_LISTEN);
|
|
return true;
|
|
}
|
|
|
|
static int sock_hash_update_common(struct bpf_map *map, void *key,
|
|
struct sock *sk, u64 flags);
|
|
|
|
int sock_map_update_elem_sys(struct bpf_map *map, void *key, void *value,
|
|
u64 flags)
|
|
{
|
|
struct socket *sock;
|
|
struct sock *sk;
|
|
int ret;
|
|
u64 ufd;
|
|
|
|
if (map->value_size == sizeof(u64))
|
|
ufd = *(u64 *)value;
|
|
else
|
|
ufd = *(u32 *)value;
|
|
if (ufd > S32_MAX)
|
|
return -EINVAL;
|
|
|
|
sock = sockfd_lookup(ufd, &ret);
|
|
if (!sock)
|
|
return ret;
|
|
sk = sock->sk;
|
|
if (!sk) {
|
|
ret = -EINVAL;
|
|
goto out;
|
|
}
|
|
if (!sock_map_sk_is_suitable(sk)) {
|
|
ret = -EOPNOTSUPP;
|
|
goto out;
|
|
}
|
|
|
|
sock_map_sk_acquire(sk);
|
|
if (!sock_map_sk_state_allowed(sk))
|
|
ret = -EOPNOTSUPP;
|
|
else if (map->map_type == BPF_MAP_TYPE_SOCKMAP)
|
|
ret = sock_map_update_common(map, *(u32 *)key, sk, flags);
|
|
else
|
|
ret = sock_hash_update_common(map, key, sk, flags);
|
|
sock_map_sk_release(sk);
|
|
out:
|
|
sockfd_put(sock);
|
|
return ret;
|
|
}
|
|
|
|
static int sock_map_update_elem(struct bpf_map *map, void *key,
|
|
void *value, u64 flags)
|
|
{
|
|
struct sock *sk = (struct sock *)value;
|
|
int ret;
|
|
|
|
if (unlikely(!sk || !sk_fullsock(sk)))
|
|
return -EINVAL;
|
|
|
|
if (!sock_map_sk_is_suitable(sk))
|
|
return -EOPNOTSUPP;
|
|
|
|
local_bh_disable();
|
|
bh_lock_sock(sk);
|
|
if (!sock_map_sk_state_allowed(sk))
|
|
ret = -EOPNOTSUPP;
|
|
else if (map->map_type == BPF_MAP_TYPE_SOCKMAP)
|
|
ret = sock_map_update_common(map, *(u32 *)key, sk, flags);
|
|
else
|
|
ret = sock_hash_update_common(map, key, sk, flags);
|
|
bh_unlock_sock(sk);
|
|
local_bh_enable();
|
|
return ret;
|
|
}
|
|
|
|
BPF_CALL_4(bpf_sock_map_update, struct bpf_sock_ops_kern *, sops,
|
|
struct bpf_map *, map, void *, key, u64, flags)
|
|
{
|
|
WARN_ON_ONCE(!rcu_read_lock_held());
|
|
|
|
if (likely(sock_map_sk_is_suitable(sops->sk) &&
|
|
sock_map_op_okay(sops)))
|
|
return sock_map_update_common(map, *(u32 *)key, sops->sk,
|
|
flags);
|
|
return -EOPNOTSUPP;
|
|
}
|
|
|
|
const struct bpf_func_proto bpf_sock_map_update_proto = {
|
|
.func = bpf_sock_map_update,
|
|
.gpl_only = false,
|
|
.pkt_access = true,
|
|
.ret_type = RET_INTEGER,
|
|
.arg1_type = ARG_PTR_TO_CTX,
|
|
.arg2_type = ARG_CONST_MAP_PTR,
|
|
.arg3_type = ARG_PTR_TO_MAP_KEY,
|
|
.arg4_type = ARG_ANYTHING,
|
|
};
|
|
|
|
BPF_CALL_4(bpf_sk_redirect_map, struct sk_buff *, skb,
|
|
struct bpf_map *, map, u32, key, u64, flags)
|
|
{
|
|
struct sock *sk;
|
|
|
|
if (unlikely(flags & ~(BPF_F_INGRESS)))
|
|
return SK_DROP;
|
|
|
|
sk = __sock_map_lookup_elem(map, key);
|
|
if (unlikely(!sk || !sock_map_redirect_allowed(sk)))
|
|
return SK_DROP;
|
|
|
|
skb_bpf_set_redir(skb, sk, flags & BPF_F_INGRESS);
|
|
return SK_PASS;
|
|
}
|
|
|
|
const struct bpf_func_proto bpf_sk_redirect_map_proto = {
|
|
.func = bpf_sk_redirect_map,
|
|
.gpl_only = false,
|
|
.ret_type = RET_INTEGER,
|
|
.arg1_type = ARG_PTR_TO_CTX,
|
|
.arg2_type = ARG_CONST_MAP_PTR,
|
|
.arg3_type = ARG_ANYTHING,
|
|
.arg4_type = ARG_ANYTHING,
|
|
};
|
|
|
|
BPF_CALL_4(bpf_msg_redirect_map, struct sk_msg *, msg,
|
|
struct bpf_map *, map, u32, key, u64, flags)
|
|
{
|
|
struct sock *sk;
|
|
|
|
if (unlikely(flags & ~(BPF_F_INGRESS)))
|
|
return SK_DROP;
|
|
|
|
sk = __sock_map_lookup_elem(map, key);
|
|
if (unlikely(!sk || !sock_map_redirect_allowed(sk)))
|
|
return SK_DROP;
|
|
|
|
msg->flags = flags;
|
|
msg->sk_redir = sk;
|
|
return SK_PASS;
|
|
}
|
|
|
|
const struct bpf_func_proto bpf_msg_redirect_map_proto = {
|
|
.func = bpf_msg_redirect_map,
|
|
.gpl_only = false,
|
|
.ret_type = RET_INTEGER,
|
|
.arg1_type = ARG_PTR_TO_CTX,
|
|
.arg2_type = ARG_CONST_MAP_PTR,
|
|
.arg3_type = ARG_ANYTHING,
|
|
.arg4_type = ARG_ANYTHING,
|
|
};
|
|
|
|
struct sock_map_seq_info {
|
|
struct bpf_map *map;
|
|
struct sock *sk;
|
|
u32 index;
|
|
};
|
|
|
|
struct bpf_iter__sockmap {
|
|
__bpf_md_ptr(struct bpf_iter_meta *, meta);
|
|
__bpf_md_ptr(struct bpf_map *, map);
|
|
__bpf_md_ptr(void *, key);
|
|
__bpf_md_ptr(struct sock *, sk);
|
|
};
|
|
|
|
DEFINE_BPF_ITER_FUNC(sockmap, struct bpf_iter_meta *meta,
|
|
struct bpf_map *map, void *key,
|
|
struct sock *sk)
|
|
|
|
static void *sock_map_seq_lookup_elem(struct sock_map_seq_info *info)
|
|
{
|
|
if (unlikely(info->index >= info->map->max_entries))
|
|
return NULL;
|
|
|
|
info->sk = __sock_map_lookup_elem(info->map, info->index);
|
|
|
|
/* can't return sk directly, since that might be NULL */
|
|
return info;
|
|
}
|
|
|
|
static void *sock_map_seq_start(struct seq_file *seq, loff_t *pos)
|
|
__acquires(rcu)
|
|
{
|
|
struct sock_map_seq_info *info = seq->private;
|
|
|
|
if (*pos == 0)
|
|
++*pos;
|
|
|
|
/* pairs with sock_map_seq_stop */
|
|
rcu_read_lock();
|
|
return sock_map_seq_lookup_elem(info);
|
|
}
|
|
|
|
static void *sock_map_seq_next(struct seq_file *seq, void *v, loff_t *pos)
|
|
__must_hold(rcu)
|
|
{
|
|
struct sock_map_seq_info *info = seq->private;
|
|
|
|
++*pos;
|
|
++info->index;
|
|
|
|
return sock_map_seq_lookup_elem(info);
|
|
}
|
|
|
|
static int sock_map_seq_show(struct seq_file *seq, void *v)
|
|
__must_hold(rcu)
|
|
{
|
|
struct sock_map_seq_info *info = seq->private;
|
|
struct bpf_iter__sockmap ctx = {};
|
|
struct bpf_iter_meta meta;
|
|
struct bpf_prog *prog;
|
|
|
|
meta.seq = seq;
|
|
prog = bpf_iter_get_info(&meta, !v);
|
|
if (!prog)
|
|
return 0;
|
|
|
|
ctx.meta = &meta;
|
|
ctx.map = info->map;
|
|
if (v) {
|
|
ctx.key = &info->index;
|
|
ctx.sk = info->sk;
|
|
}
|
|
|
|
return bpf_iter_run_prog(prog, &ctx);
|
|
}
|
|
|
|
static void sock_map_seq_stop(struct seq_file *seq, void *v)
|
|
__releases(rcu)
|
|
{
|
|
if (!v)
|
|
(void)sock_map_seq_show(seq, NULL);
|
|
|
|
/* pairs with sock_map_seq_start */
|
|
rcu_read_unlock();
|
|
}
|
|
|
|
static const struct seq_operations sock_map_seq_ops = {
|
|
.start = sock_map_seq_start,
|
|
.next = sock_map_seq_next,
|
|
.stop = sock_map_seq_stop,
|
|
.show = sock_map_seq_show,
|
|
};
|
|
|
|
static int sock_map_init_seq_private(void *priv_data,
|
|
struct bpf_iter_aux_info *aux)
|
|
{
|
|
struct sock_map_seq_info *info = priv_data;
|
|
|
|
info->map = aux->map;
|
|
return 0;
|
|
}
|
|
|
|
static const struct bpf_iter_seq_info sock_map_iter_seq_info = {
|
|
.seq_ops = &sock_map_seq_ops,
|
|
.init_seq_private = sock_map_init_seq_private,
|
|
.seq_priv_size = sizeof(struct sock_map_seq_info),
|
|
};
|
|
|
|
static int sock_map_btf_id;
|
|
const struct bpf_map_ops sock_map_ops = {
|
|
.map_meta_equal = bpf_map_meta_equal,
|
|
.map_alloc = sock_map_alloc,
|
|
.map_free = sock_map_free,
|
|
.map_get_next_key = sock_map_get_next_key,
|
|
.map_lookup_elem_sys_only = sock_map_lookup_sys,
|
|
.map_update_elem = sock_map_update_elem,
|
|
.map_delete_elem = sock_map_delete_elem,
|
|
.map_lookup_elem = sock_map_lookup,
|
|
.map_release_uref = sock_map_release_progs,
|
|
.map_check_btf = map_check_no_btf,
|
|
.map_btf_name = "bpf_stab",
|
|
.map_btf_id = &sock_map_btf_id,
|
|
.iter_seq_info = &sock_map_iter_seq_info,
|
|
};
|
|
|
|
struct bpf_shtab_elem {
|
|
struct rcu_head rcu;
|
|
u32 hash;
|
|
struct sock *sk;
|
|
struct hlist_node node;
|
|
u8 key[];
|
|
};
|
|
|
|
struct bpf_shtab_bucket {
|
|
struct hlist_head head;
|
|
raw_spinlock_t lock;
|
|
};
|
|
|
|
struct bpf_shtab {
|
|
struct bpf_map map;
|
|
struct bpf_shtab_bucket *buckets;
|
|
u32 buckets_num;
|
|
u32 elem_size;
|
|
struct sk_psock_progs progs;
|
|
atomic_t count;
|
|
};
|
|
|
|
static inline u32 sock_hash_bucket_hash(const void *key, u32 len)
|
|
{
|
|
return jhash(key, len, 0);
|
|
}
|
|
|
|
static struct bpf_shtab_bucket *sock_hash_select_bucket(struct bpf_shtab *htab,
|
|
u32 hash)
|
|
{
|
|
return &htab->buckets[hash & (htab->buckets_num - 1)];
|
|
}
|
|
|
|
static struct bpf_shtab_elem *
|
|
sock_hash_lookup_elem_raw(struct hlist_head *head, u32 hash, void *key,
|
|
u32 key_size)
|
|
{
|
|
struct bpf_shtab_elem *elem;
|
|
|
|
hlist_for_each_entry_rcu(elem, head, node) {
|
|
if (elem->hash == hash &&
|
|
!memcmp(&elem->key, key, key_size))
|
|
return elem;
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
static struct sock *__sock_hash_lookup_elem(struct bpf_map *map, void *key)
|
|
{
|
|
struct bpf_shtab *htab = container_of(map, struct bpf_shtab, map);
|
|
u32 key_size = map->key_size, hash;
|
|
struct bpf_shtab_bucket *bucket;
|
|
struct bpf_shtab_elem *elem;
|
|
|
|
WARN_ON_ONCE(!rcu_read_lock_held());
|
|
|
|
hash = sock_hash_bucket_hash(key, key_size);
|
|
bucket = sock_hash_select_bucket(htab, hash);
|
|
elem = sock_hash_lookup_elem_raw(&bucket->head, hash, key, key_size);
|
|
|
|
return elem ? elem->sk : NULL;
|
|
}
|
|
|
|
static void sock_hash_free_elem(struct bpf_shtab *htab,
|
|
struct bpf_shtab_elem *elem)
|
|
{
|
|
atomic_dec(&htab->count);
|
|
kfree_rcu(elem, rcu);
|
|
}
|
|
|
|
static void sock_hash_delete_from_link(struct bpf_map *map, struct sock *sk,
|
|
void *link_raw)
|
|
{
|
|
struct bpf_shtab *htab = container_of(map, struct bpf_shtab, map);
|
|
struct bpf_shtab_elem *elem_probe, *elem = link_raw;
|
|
struct bpf_shtab_bucket *bucket;
|
|
|
|
WARN_ON_ONCE(!rcu_read_lock_held());
|
|
bucket = sock_hash_select_bucket(htab, elem->hash);
|
|
|
|
/* elem may be deleted in parallel from the map, but access here
|
|
* is okay since it's going away only after RCU grace period.
|
|
* However, we need to check whether it's still present.
|
|
*/
|
|
raw_spin_lock_bh(&bucket->lock);
|
|
elem_probe = sock_hash_lookup_elem_raw(&bucket->head, elem->hash,
|
|
elem->key, map->key_size);
|
|
if (elem_probe && elem_probe == elem) {
|
|
hlist_del_rcu(&elem->node);
|
|
sock_map_unref(elem->sk, elem);
|
|
sock_hash_free_elem(htab, elem);
|
|
}
|
|
raw_spin_unlock_bh(&bucket->lock);
|
|
}
|
|
|
|
static int sock_hash_delete_elem(struct bpf_map *map, void *key)
|
|
{
|
|
struct bpf_shtab *htab = container_of(map, struct bpf_shtab, map);
|
|
u32 hash, key_size = map->key_size;
|
|
struct bpf_shtab_bucket *bucket;
|
|
struct bpf_shtab_elem *elem;
|
|
int ret = -ENOENT;
|
|
|
|
hash = sock_hash_bucket_hash(key, key_size);
|
|
bucket = sock_hash_select_bucket(htab, hash);
|
|
|
|
raw_spin_lock_bh(&bucket->lock);
|
|
elem = sock_hash_lookup_elem_raw(&bucket->head, hash, key, key_size);
|
|
if (elem) {
|
|
hlist_del_rcu(&elem->node);
|
|
sock_map_unref(elem->sk, elem);
|
|
sock_hash_free_elem(htab, elem);
|
|
ret = 0;
|
|
}
|
|
raw_spin_unlock_bh(&bucket->lock);
|
|
return ret;
|
|
}
|
|
|
|
static struct bpf_shtab_elem *sock_hash_alloc_elem(struct bpf_shtab *htab,
|
|
void *key, u32 key_size,
|
|
u32 hash, struct sock *sk,
|
|
struct bpf_shtab_elem *old)
|
|
{
|
|
struct bpf_shtab_elem *new;
|
|
|
|
if (atomic_inc_return(&htab->count) > htab->map.max_entries) {
|
|
if (!old) {
|
|
atomic_dec(&htab->count);
|
|
return ERR_PTR(-E2BIG);
|
|
}
|
|
}
|
|
|
|
new = bpf_map_kmalloc_node(&htab->map, htab->elem_size,
|
|
GFP_ATOMIC | __GFP_NOWARN,
|
|
htab->map.numa_node);
|
|
if (!new) {
|
|
atomic_dec(&htab->count);
|
|
return ERR_PTR(-ENOMEM);
|
|
}
|
|
memcpy(new->key, key, key_size);
|
|
new->sk = sk;
|
|
new->hash = hash;
|
|
return new;
|
|
}
|
|
|
|
static int sock_hash_update_common(struct bpf_map *map, void *key,
|
|
struct sock *sk, u64 flags)
|
|
{
|
|
struct bpf_shtab *htab = container_of(map, struct bpf_shtab, map);
|
|
u32 key_size = map->key_size, hash;
|
|
struct bpf_shtab_elem *elem, *elem_new;
|
|
struct bpf_shtab_bucket *bucket;
|
|
struct sk_psock_link *link;
|
|
struct sk_psock *psock;
|
|
int ret;
|
|
|
|
WARN_ON_ONCE(!rcu_read_lock_held());
|
|
if (unlikely(flags > BPF_EXIST))
|
|
return -EINVAL;
|
|
|
|
link = sk_psock_init_link();
|
|
if (!link)
|
|
return -ENOMEM;
|
|
|
|
ret = sock_map_link(map, sk);
|
|
if (ret < 0)
|
|
goto out_free;
|
|
|
|
psock = sk_psock(sk);
|
|
WARN_ON_ONCE(!psock);
|
|
|
|
hash = sock_hash_bucket_hash(key, key_size);
|
|
bucket = sock_hash_select_bucket(htab, hash);
|
|
|
|
raw_spin_lock_bh(&bucket->lock);
|
|
elem = sock_hash_lookup_elem_raw(&bucket->head, hash, key, key_size);
|
|
if (elem && flags == BPF_NOEXIST) {
|
|
ret = -EEXIST;
|
|
goto out_unlock;
|
|
} else if (!elem && flags == BPF_EXIST) {
|
|
ret = -ENOENT;
|
|
goto out_unlock;
|
|
}
|
|
|
|
elem_new = sock_hash_alloc_elem(htab, key, key_size, hash, sk, elem);
|
|
if (IS_ERR(elem_new)) {
|
|
ret = PTR_ERR(elem_new);
|
|
goto out_unlock;
|
|
}
|
|
|
|
sock_map_add_link(psock, link, map, elem_new);
|
|
/* Add new element to the head of the list, so that
|
|
* concurrent search will find it before old elem.
|
|
*/
|
|
hlist_add_head_rcu(&elem_new->node, &bucket->head);
|
|
if (elem) {
|
|
hlist_del_rcu(&elem->node);
|
|
sock_map_unref(elem->sk, elem);
|
|
sock_hash_free_elem(htab, elem);
|
|
}
|
|
raw_spin_unlock_bh(&bucket->lock);
|
|
return 0;
|
|
out_unlock:
|
|
raw_spin_unlock_bh(&bucket->lock);
|
|
sk_psock_put(sk, psock);
|
|
out_free:
|
|
sk_psock_free_link(link);
|
|
return ret;
|
|
}
|
|
|
|
static int sock_hash_get_next_key(struct bpf_map *map, void *key,
|
|
void *key_next)
|
|
{
|
|
struct bpf_shtab *htab = container_of(map, struct bpf_shtab, map);
|
|
struct bpf_shtab_elem *elem, *elem_next;
|
|
u32 hash, key_size = map->key_size;
|
|
struct hlist_head *head;
|
|
int i = 0;
|
|
|
|
if (!key)
|
|
goto find_first_elem;
|
|
hash = sock_hash_bucket_hash(key, key_size);
|
|
head = &sock_hash_select_bucket(htab, hash)->head;
|
|
elem = sock_hash_lookup_elem_raw(head, hash, key, key_size);
|
|
if (!elem)
|
|
goto find_first_elem;
|
|
|
|
elem_next = hlist_entry_safe(rcu_dereference(hlist_next_rcu(&elem->node)),
|
|
struct bpf_shtab_elem, node);
|
|
if (elem_next) {
|
|
memcpy(key_next, elem_next->key, key_size);
|
|
return 0;
|
|
}
|
|
|
|
i = hash & (htab->buckets_num - 1);
|
|
i++;
|
|
find_first_elem:
|
|
for (; i < htab->buckets_num; i++) {
|
|
head = &sock_hash_select_bucket(htab, i)->head;
|
|
elem_next = hlist_entry_safe(rcu_dereference(hlist_first_rcu(head)),
|
|
struct bpf_shtab_elem, node);
|
|
if (elem_next) {
|
|
memcpy(key_next, elem_next->key, key_size);
|
|
return 0;
|
|
}
|
|
}
|
|
|
|
return -ENOENT;
|
|
}
|
|
|
|
static struct bpf_map *sock_hash_alloc(union bpf_attr *attr)
|
|
{
|
|
struct bpf_shtab *htab;
|
|
int i, err;
|
|
|
|
if (!capable(CAP_NET_ADMIN))
|
|
return ERR_PTR(-EPERM);
|
|
if (attr->max_entries == 0 ||
|
|
attr->key_size == 0 ||
|
|
(attr->value_size != sizeof(u32) &&
|
|
attr->value_size != sizeof(u64)) ||
|
|
attr->map_flags & ~SOCK_CREATE_FLAG_MASK)
|
|
return ERR_PTR(-EINVAL);
|
|
if (attr->key_size > MAX_BPF_STACK)
|
|
return ERR_PTR(-E2BIG);
|
|
|
|
htab = kzalloc(sizeof(*htab), GFP_USER | __GFP_ACCOUNT);
|
|
if (!htab)
|
|
return ERR_PTR(-ENOMEM);
|
|
|
|
bpf_map_init_from_attr(&htab->map, attr);
|
|
|
|
htab->buckets_num = roundup_pow_of_two(htab->map.max_entries);
|
|
htab->elem_size = sizeof(struct bpf_shtab_elem) +
|
|
round_up(htab->map.key_size, 8);
|
|
if (htab->buckets_num == 0 ||
|
|
htab->buckets_num > U32_MAX / sizeof(struct bpf_shtab_bucket)) {
|
|
err = -EINVAL;
|
|
goto free_htab;
|
|
}
|
|
|
|
htab->buckets = bpf_map_area_alloc(htab->buckets_num *
|
|
sizeof(struct bpf_shtab_bucket),
|
|
htab->map.numa_node);
|
|
if (!htab->buckets) {
|
|
err = -ENOMEM;
|
|
goto free_htab;
|
|
}
|
|
|
|
for (i = 0; i < htab->buckets_num; i++) {
|
|
INIT_HLIST_HEAD(&htab->buckets[i].head);
|
|
raw_spin_lock_init(&htab->buckets[i].lock);
|
|
}
|
|
|
|
return &htab->map;
|
|
free_htab:
|
|
kfree(htab);
|
|
return ERR_PTR(err);
|
|
}
|
|
|
|
static void sock_hash_free(struct bpf_map *map)
|
|
{
|
|
struct bpf_shtab *htab = container_of(map, struct bpf_shtab, map);
|
|
struct bpf_shtab_bucket *bucket;
|
|
struct hlist_head unlink_list;
|
|
struct bpf_shtab_elem *elem;
|
|
struct hlist_node *node;
|
|
int i;
|
|
|
|
/* After the sync no updates or deletes will be in-flight so it
|
|
* is safe to walk map and remove entries without risking a race
|
|
* in EEXIST update case.
|
|
*/
|
|
synchronize_rcu();
|
|
for (i = 0; i < htab->buckets_num; i++) {
|
|
bucket = sock_hash_select_bucket(htab, i);
|
|
|
|
/* We are racing with sock_hash_delete_from_link to
|
|
* enter the spin-lock critical section. Every socket on
|
|
* the list is still linked to sockhash. Since link
|
|
* exists, psock exists and holds a ref to socket. That
|
|
* lets us to grab a socket ref too.
|
|
*/
|
|
raw_spin_lock_bh(&bucket->lock);
|
|
hlist_for_each_entry(elem, &bucket->head, node)
|
|
sock_hold(elem->sk);
|
|
hlist_move_list(&bucket->head, &unlink_list);
|
|
raw_spin_unlock_bh(&bucket->lock);
|
|
|
|
/* Process removed entries out of atomic context to
|
|
* block for socket lock before deleting the psock's
|
|
* link to sockhash.
|
|
*/
|
|
hlist_for_each_entry_safe(elem, node, &unlink_list, node) {
|
|
hlist_del(&elem->node);
|
|
lock_sock(elem->sk);
|
|
rcu_read_lock();
|
|
sock_map_unref(elem->sk, elem);
|
|
rcu_read_unlock();
|
|
release_sock(elem->sk);
|
|
sock_put(elem->sk);
|
|
sock_hash_free_elem(htab, elem);
|
|
}
|
|
}
|
|
|
|
/* wait for psock readers accessing its map link */
|
|
synchronize_rcu();
|
|
|
|
bpf_map_area_free(htab->buckets);
|
|
kfree(htab);
|
|
}
|
|
|
|
static void *sock_hash_lookup_sys(struct bpf_map *map, void *key)
|
|
{
|
|
struct sock *sk;
|
|
|
|
if (map->value_size != sizeof(u64))
|
|
return ERR_PTR(-ENOSPC);
|
|
|
|
sk = __sock_hash_lookup_elem(map, key);
|
|
if (!sk)
|
|
return ERR_PTR(-ENOENT);
|
|
|
|
__sock_gen_cookie(sk);
|
|
return &sk->sk_cookie;
|
|
}
|
|
|
|
static void *sock_hash_lookup(struct bpf_map *map, void *key)
|
|
{
|
|
struct sock *sk;
|
|
|
|
sk = __sock_hash_lookup_elem(map, key);
|
|
if (!sk)
|
|
return NULL;
|
|
if (sk_is_refcounted(sk) && !refcount_inc_not_zero(&sk->sk_refcnt))
|
|
return NULL;
|
|
return sk;
|
|
}
|
|
|
|
static void sock_hash_release_progs(struct bpf_map *map)
|
|
{
|
|
psock_progs_drop(&container_of(map, struct bpf_shtab, map)->progs);
|
|
}
|
|
|
|
BPF_CALL_4(bpf_sock_hash_update, struct bpf_sock_ops_kern *, sops,
|
|
struct bpf_map *, map, void *, key, u64, flags)
|
|
{
|
|
WARN_ON_ONCE(!rcu_read_lock_held());
|
|
|
|
if (likely(sock_map_sk_is_suitable(sops->sk) &&
|
|
sock_map_op_okay(sops)))
|
|
return sock_hash_update_common(map, key, sops->sk, flags);
|
|
return -EOPNOTSUPP;
|
|
}
|
|
|
|
const struct bpf_func_proto bpf_sock_hash_update_proto = {
|
|
.func = bpf_sock_hash_update,
|
|
.gpl_only = false,
|
|
.pkt_access = true,
|
|
.ret_type = RET_INTEGER,
|
|
.arg1_type = ARG_PTR_TO_CTX,
|
|
.arg2_type = ARG_CONST_MAP_PTR,
|
|
.arg3_type = ARG_PTR_TO_MAP_KEY,
|
|
.arg4_type = ARG_ANYTHING,
|
|
};
|
|
|
|
BPF_CALL_4(bpf_sk_redirect_hash, struct sk_buff *, skb,
|
|
struct bpf_map *, map, void *, key, u64, flags)
|
|
{
|
|
struct sock *sk;
|
|
|
|
if (unlikely(flags & ~(BPF_F_INGRESS)))
|
|
return SK_DROP;
|
|
|
|
sk = __sock_hash_lookup_elem(map, key);
|
|
if (unlikely(!sk || !sock_map_redirect_allowed(sk)))
|
|
return SK_DROP;
|
|
|
|
skb_bpf_set_redir(skb, sk, flags & BPF_F_INGRESS);
|
|
return SK_PASS;
|
|
}
|
|
|
|
const struct bpf_func_proto bpf_sk_redirect_hash_proto = {
|
|
.func = bpf_sk_redirect_hash,
|
|
.gpl_only = false,
|
|
.ret_type = RET_INTEGER,
|
|
.arg1_type = ARG_PTR_TO_CTX,
|
|
.arg2_type = ARG_CONST_MAP_PTR,
|
|
.arg3_type = ARG_PTR_TO_MAP_KEY,
|
|
.arg4_type = ARG_ANYTHING,
|
|
};
|
|
|
|
BPF_CALL_4(bpf_msg_redirect_hash, struct sk_msg *, msg,
|
|
struct bpf_map *, map, void *, key, u64, flags)
|
|
{
|
|
struct sock *sk;
|
|
|
|
if (unlikely(flags & ~(BPF_F_INGRESS)))
|
|
return SK_DROP;
|
|
|
|
sk = __sock_hash_lookup_elem(map, key);
|
|
if (unlikely(!sk || !sock_map_redirect_allowed(sk)))
|
|
return SK_DROP;
|
|
|
|
msg->flags = flags;
|
|
msg->sk_redir = sk;
|
|
return SK_PASS;
|
|
}
|
|
|
|
const struct bpf_func_proto bpf_msg_redirect_hash_proto = {
|
|
.func = bpf_msg_redirect_hash,
|
|
.gpl_only = false,
|
|
.ret_type = RET_INTEGER,
|
|
.arg1_type = ARG_PTR_TO_CTX,
|
|
.arg2_type = ARG_CONST_MAP_PTR,
|
|
.arg3_type = ARG_PTR_TO_MAP_KEY,
|
|
.arg4_type = ARG_ANYTHING,
|
|
};
|
|
|
|
struct sock_hash_seq_info {
|
|
struct bpf_map *map;
|
|
struct bpf_shtab *htab;
|
|
u32 bucket_id;
|
|
};
|
|
|
|
static void *sock_hash_seq_find_next(struct sock_hash_seq_info *info,
|
|
struct bpf_shtab_elem *prev_elem)
|
|
{
|
|
const struct bpf_shtab *htab = info->htab;
|
|
struct bpf_shtab_bucket *bucket;
|
|
struct bpf_shtab_elem *elem;
|
|
struct hlist_node *node;
|
|
|
|
/* try to find next elem in the same bucket */
|
|
if (prev_elem) {
|
|
node = rcu_dereference(hlist_next_rcu(&prev_elem->node));
|
|
elem = hlist_entry_safe(node, struct bpf_shtab_elem, node);
|
|
if (elem)
|
|
return elem;
|
|
|
|
/* no more elements, continue in the next bucket */
|
|
info->bucket_id++;
|
|
}
|
|
|
|
for (; info->bucket_id < htab->buckets_num; info->bucket_id++) {
|
|
bucket = &htab->buckets[info->bucket_id];
|
|
node = rcu_dereference(hlist_first_rcu(&bucket->head));
|
|
elem = hlist_entry_safe(node, struct bpf_shtab_elem, node);
|
|
if (elem)
|
|
return elem;
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
static void *sock_hash_seq_start(struct seq_file *seq, loff_t *pos)
|
|
__acquires(rcu)
|
|
{
|
|
struct sock_hash_seq_info *info = seq->private;
|
|
|
|
if (*pos == 0)
|
|
++*pos;
|
|
|
|
/* pairs with sock_hash_seq_stop */
|
|
rcu_read_lock();
|
|
return sock_hash_seq_find_next(info, NULL);
|
|
}
|
|
|
|
static void *sock_hash_seq_next(struct seq_file *seq, void *v, loff_t *pos)
|
|
__must_hold(rcu)
|
|
{
|
|
struct sock_hash_seq_info *info = seq->private;
|
|
|
|
++*pos;
|
|
return sock_hash_seq_find_next(info, v);
|
|
}
|
|
|
|
static int sock_hash_seq_show(struct seq_file *seq, void *v)
|
|
__must_hold(rcu)
|
|
{
|
|
struct sock_hash_seq_info *info = seq->private;
|
|
struct bpf_iter__sockmap ctx = {};
|
|
struct bpf_shtab_elem *elem = v;
|
|
struct bpf_iter_meta meta;
|
|
struct bpf_prog *prog;
|
|
|
|
meta.seq = seq;
|
|
prog = bpf_iter_get_info(&meta, !elem);
|
|
if (!prog)
|
|
return 0;
|
|
|
|
ctx.meta = &meta;
|
|
ctx.map = info->map;
|
|
if (elem) {
|
|
ctx.key = elem->key;
|
|
ctx.sk = elem->sk;
|
|
}
|
|
|
|
return bpf_iter_run_prog(prog, &ctx);
|
|
}
|
|
|
|
static void sock_hash_seq_stop(struct seq_file *seq, void *v)
|
|
__releases(rcu)
|
|
{
|
|
if (!v)
|
|
(void)sock_hash_seq_show(seq, NULL);
|
|
|
|
/* pairs with sock_hash_seq_start */
|
|
rcu_read_unlock();
|
|
}
|
|
|
|
static const struct seq_operations sock_hash_seq_ops = {
|
|
.start = sock_hash_seq_start,
|
|
.next = sock_hash_seq_next,
|
|
.stop = sock_hash_seq_stop,
|
|
.show = sock_hash_seq_show,
|
|
};
|
|
|
|
static int sock_hash_init_seq_private(void *priv_data,
|
|
struct bpf_iter_aux_info *aux)
|
|
{
|
|
struct sock_hash_seq_info *info = priv_data;
|
|
|
|
info->map = aux->map;
|
|
info->htab = container_of(aux->map, struct bpf_shtab, map);
|
|
return 0;
|
|
}
|
|
|
|
static const struct bpf_iter_seq_info sock_hash_iter_seq_info = {
|
|
.seq_ops = &sock_hash_seq_ops,
|
|
.init_seq_private = sock_hash_init_seq_private,
|
|
.seq_priv_size = sizeof(struct sock_hash_seq_info),
|
|
};
|
|
|
|
static int sock_hash_map_btf_id;
|
|
const struct bpf_map_ops sock_hash_ops = {
|
|
.map_meta_equal = bpf_map_meta_equal,
|
|
.map_alloc = sock_hash_alloc,
|
|
.map_free = sock_hash_free,
|
|
.map_get_next_key = sock_hash_get_next_key,
|
|
.map_update_elem = sock_map_update_elem,
|
|
.map_delete_elem = sock_hash_delete_elem,
|
|
.map_lookup_elem = sock_hash_lookup,
|
|
.map_lookup_elem_sys_only = sock_hash_lookup_sys,
|
|
.map_release_uref = sock_hash_release_progs,
|
|
.map_check_btf = map_check_no_btf,
|
|
.map_btf_name = "bpf_shtab",
|
|
.map_btf_id = &sock_hash_map_btf_id,
|
|
.iter_seq_info = &sock_hash_iter_seq_info,
|
|
};
|
|
|
|
static struct sk_psock_progs *sock_map_progs(struct bpf_map *map)
|
|
{
|
|
switch (map->map_type) {
|
|
case BPF_MAP_TYPE_SOCKMAP:
|
|
return &container_of(map, struct bpf_stab, map)->progs;
|
|
case BPF_MAP_TYPE_SOCKHASH:
|
|
return &container_of(map, struct bpf_shtab, map)->progs;
|
|
default:
|
|
break;
|
|
}
|
|
|
|
return NULL;
|
|
}
|
|
|
|
static int sock_map_prog_update(struct bpf_map *map, struct bpf_prog *prog,
|
|
struct bpf_prog *old, u32 which)
|
|
{
|
|
struct sk_psock_progs *progs = sock_map_progs(map);
|
|
struct bpf_prog **pprog;
|
|
|
|
if (!progs)
|
|
return -EOPNOTSUPP;
|
|
|
|
switch (which) {
|
|
case BPF_SK_MSG_VERDICT:
|
|
pprog = &progs->msg_parser;
|
|
break;
|
|
#if IS_ENABLED(CONFIG_BPF_STREAM_PARSER)
|
|
case BPF_SK_SKB_STREAM_PARSER:
|
|
pprog = &progs->stream_parser;
|
|
break;
|
|
#endif
|
|
case BPF_SK_SKB_STREAM_VERDICT:
|
|
if (progs->skb_verdict)
|
|
return -EBUSY;
|
|
pprog = &progs->stream_verdict;
|
|
break;
|
|
case BPF_SK_SKB_VERDICT:
|
|
if (progs->stream_verdict)
|
|
return -EBUSY;
|
|
pprog = &progs->skb_verdict;
|
|
break;
|
|
default:
|
|
return -EOPNOTSUPP;
|
|
}
|
|
|
|
if (old)
|
|
return psock_replace_prog(pprog, prog, old);
|
|
|
|
psock_set_prog(pprog, prog);
|
|
return 0;
|
|
}
|
|
|
|
static void sock_map_unlink(struct sock *sk, struct sk_psock_link *link)
|
|
{
|
|
switch (link->map->map_type) {
|
|
case BPF_MAP_TYPE_SOCKMAP:
|
|
return sock_map_delete_from_link(link->map, sk,
|
|
link->link_raw);
|
|
case BPF_MAP_TYPE_SOCKHASH:
|
|
return sock_hash_delete_from_link(link->map, sk,
|
|
link->link_raw);
|
|
default:
|
|
break;
|
|
}
|
|
}
|
|
|
|
static void sock_map_remove_links(struct sock *sk, struct sk_psock *psock)
|
|
{
|
|
struct sk_psock_link *link;
|
|
|
|
while ((link = sk_psock_link_pop(psock))) {
|
|
sock_map_unlink(sk, link);
|
|
sk_psock_free_link(link);
|
|
}
|
|
}
|
|
|
|
void sock_map_unhash(struct sock *sk)
|
|
{
|
|
void (*saved_unhash)(struct sock *sk);
|
|
struct sk_psock *psock;
|
|
|
|
rcu_read_lock();
|
|
psock = sk_psock(sk);
|
|
if (unlikely(!psock)) {
|
|
rcu_read_unlock();
|
|
if (sk->sk_prot->unhash)
|
|
sk->sk_prot->unhash(sk);
|
|
return;
|
|
}
|
|
|
|
saved_unhash = psock->saved_unhash;
|
|
sock_map_remove_links(sk, psock);
|
|
rcu_read_unlock();
|
|
saved_unhash(sk);
|
|
}
|
|
EXPORT_SYMBOL_GPL(sock_map_unhash);
|
|
|
|
void sock_map_close(struct sock *sk, long timeout)
|
|
{
|
|
void (*saved_close)(struct sock *sk, long timeout);
|
|
struct sk_psock *psock;
|
|
|
|
lock_sock(sk);
|
|
rcu_read_lock();
|
|
psock = sk_psock_get(sk);
|
|
if (unlikely(!psock)) {
|
|
rcu_read_unlock();
|
|
release_sock(sk);
|
|
return sk->sk_prot->close(sk, timeout);
|
|
}
|
|
|
|
saved_close = psock->saved_close;
|
|
sock_map_remove_links(sk, psock);
|
|
rcu_read_unlock();
|
|
sk_psock_stop(psock, true);
|
|
sk_psock_put(sk, psock);
|
|
release_sock(sk);
|
|
saved_close(sk, timeout);
|
|
}
|
|
EXPORT_SYMBOL_GPL(sock_map_close);
|
|
|
|
static int sock_map_iter_attach_target(struct bpf_prog *prog,
|
|
union bpf_iter_link_info *linfo,
|
|
struct bpf_iter_aux_info *aux)
|
|
{
|
|
struct bpf_map *map;
|
|
int err = -EINVAL;
|
|
|
|
if (!linfo->map.map_fd)
|
|
return -EBADF;
|
|
|
|
map = bpf_map_get_with_uref(linfo->map.map_fd);
|
|
if (IS_ERR(map))
|
|
return PTR_ERR(map);
|
|
|
|
if (map->map_type != BPF_MAP_TYPE_SOCKMAP &&
|
|
map->map_type != BPF_MAP_TYPE_SOCKHASH)
|
|
goto put_map;
|
|
|
|
if (prog->aux->max_rdonly_access > map->key_size) {
|
|
err = -EACCES;
|
|
goto put_map;
|
|
}
|
|
|
|
aux->map = map;
|
|
return 0;
|
|
|
|
put_map:
|
|
bpf_map_put_with_uref(map);
|
|
return err;
|
|
}
|
|
|
|
static void sock_map_iter_detach_target(struct bpf_iter_aux_info *aux)
|
|
{
|
|
bpf_map_put_with_uref(aux->map);
|
|
}
|
|
|
|
static struct bpf_iter_reg sock_map_iter_reg = {
|
|
.target = "sockmap",
|
|
.attach_target = sock_map_iter_attach_target,
|
|
.detach_target = sock_map_iter_detach_target,
|
|
.show_fdinfo = bpf_iter_map_show_fdinfo,
|
|
.fill_link_info = bpf_iter_map_fill_link_info,
|
|
.ctx_arg_info_size = 2,
|
|
.ctx_arg_info = {
|
|
{ offsetof(struct bpf_iter__sockmap, key),
|
|
PTR_TO_RDONLY_BUF_OR_NULL },
|
|
{ offsetof(struct bpf_iter__sockmap, sk),
|
|
PTR_TO_BTF_ID_OR_NULL },
|
|
},
|
|
};
|
|
|
|
static int __init bpf_sockmap_iter_init(void)
|
|
{
|
|
sock_map_iter_reg.ctx_arg_info[1].btf_id =
|
|
btf_sock_ids[BTF_SOCK_TYPE_SOCK];
|
|
return bpf_iter_reg_target(&sock_map_iter_reg);
|
|
}
|
|
late_initcall(bpf_sockmap_iter_init);
|