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https://git.kernel.org/pub/scm/linux/kernel/git/stable/linux.git
synced 2024-09-04 09:59:32 +00:00
![John Fastabend](/assets/img/avatar_default.png)
A sockmap program that redirects through a kTLS ULP enabled socket
will not work correctly because the ULP layer is skipped. This
fixes the behavior to call through the ULP layer on redirect to
ensure any operations required on the data stream at the ULP layer
continue to be applied.
To do this we add an internal flag MSG_SENDPAGE_NOPOLICY to avoid
calling the BPF layer on a redirected message. This is
required to avoid calling the BPF layer multiple times (possibly
recursively) which is not the current/expected behavior without
ULPs. In the future we may add a redirect flag if users _do_
want the policy applied again but this would need to work for both
ULP and non-ULP sockets and be opt-in to avoid breaking existing
programs.
Also to avoid polluting the flag space with an internal flag we
reuse the flag space overlapping MSG_SENDPAGE_NOPOLICY with
MSG_WAITFORONE. Here WAITFORONE is specific to recv path and
SENDPAGE_NOPOLICY is only used for sendpage hooks. The last thing
to verify is user space API is masked correctly to ensure the flag
can not be set by user. (Note this needs to be true regardless
because we have internal flags already in-use that user space
should not be able to set). But for completeness we have two UAPI
paths into sendpage, sendfile and splice.
In the sendfile case the function do_sendfile() zero's flags,
./fs/read_write.c:
static ssize_t do_sendfile(int out_fd, int in_fd, loff_t *ppos,
size_t count, loff_t max)
{
...
fl = 0;
#if 0
/*
* We need to debate whether we can enable this or not. The
* man page documents EAGAIN return for the output at least,
* and the application is arguably buggy if it doesn't expect
* EAGAIN on a non-blocking file descriptor.
*/
if (in.file->f_flags & O_NONBLOCK)
fl = SPLICE_F_NONBLOCK;
#endif
file_start_write(out.file);
retval = do_splice_direct(in.file, &pos, out.file, &out_pos, count, fl);
}
In the splice case the pipe_to_sendpage "actor" is used which
masks flags with SPLICE_F_MORE.
./fs/splice.c:
static int pipe_to_sendpage(struct pipe_inode_info *pipe,
struct pipe_buffer *buf, struct splice_desc *sd)
{
...
more = (sd->flags & SPLICE_F_MORE) ? MSG_MORE : 0;
...
}
Confirming what we expect that internal flags are in fact internal
to socket side.
Fixes: d3b18ad31f
("tls: add bpf support to sk_msg handling")
Signed-off-by: John Fastabend <john.fastabend@gmail.com>
Signed-off-by: Daniel Borkmann <daniel@iogearbox.net>
691 lines
16 KiB
C
691 lines
16 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/skmsg.h>
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#include <linux/filter.h>
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#include <linux/bpf.h>
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#include <linux/init.h>
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#include <linux/wait.h>
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#include <net/inet_common.h>
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#include <net/tls.h>
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static bool tcp_bpf_stream_read(const struct sock *sk)
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{
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struct sk_psock *psock;
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bool empty = true;
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rcu_read_lock();
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psock = sk_psock(sk);
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if (likely(psock))
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empty = list_empty(&psock->ingress_msg);
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rcu_read_unlock();
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return !empty;
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}
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static int tcp_bpf_wait_data(struct sock *sk, struct sk_psock *psock,
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int flags, long timeo, int *err)
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{
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DEFINE_WAIT_FUNC(wait, woken_wake_function);
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int ret;
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add_wait_queue(sk_sleep(sk), &wait);
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sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk);
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ret = sk_wait_event(sk, &timeo,
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!list_empty(&psock->ingress_msg) ||
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!skb_queue_empty(&sk->sk_receive_queue), &wait);
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sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk);
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remove_wait_queue(sk_sleep(sk), &wait);
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return ret;
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}
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int __tcp_bpf_recvmsg(struct sock *sk, struct sk_psock *psock,
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struct msghdr *msg, int len, int flags)
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{
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struct iov_iter *iter = &msg->msg_iter;
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int peek = flags & MSG_PEEK;
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int i, ret, copied = 0;
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struct sk_msg *msg_rx;
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msg_rx = list_first_entry_or_null(&psock->ingress_msg,
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struct sk_msg, list);
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while (copied != len) {
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struct scatterlist *sge;
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if (unlikely(!msg_rx))
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break;
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i = msg_rx->sg.start;
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do {
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struct page *page;
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int copy;
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sge = sk_msg_elem(msg_rx, i);
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copy = sge->length;
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page = sg_page(sge);
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if (copied + copy > len)
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copy = len - copied;
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ret = copy_page_to_iter(page, sge->offset, copy, iter);
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if (ret != copy) {
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msg_rx->sg.start = i;
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return -EFAULT;
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}
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copied += copy;
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if (likely(!peek)) {
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sge->offset += copy;
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sge->length -= copy;
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sk_mem_uncharge(sk, copy);
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msg_rx->sg.size -= copy;
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if (!sge->length) {
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sk_msg_iter_var_next(i);
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if (!msg_rx->skb)
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put_page(page);
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}
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} else {
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sk_msg_iter_var_next(i);
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}
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if (copied == len)
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break;
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} while (i != msg_rx->sg.end);
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if (unlikely(peek)) {
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msg_rx = list_next_entry(msg_rx, list);
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continue;
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}
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msg_rx->sg.start = i;
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if (!sge->length && msg_rx->sg.start == msg_rx->sg.end) {
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list_del(&msg_rx->list);
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if (msg_rx->skb)
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consume_skb(msg_rx->skb);
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kfree(msg_rx);
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}
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msg_rx = list_first_entry_or_null(&psock->ingress_msg,
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struct sk_msg, list);
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}
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return copied;
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}
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EXPORT_SYMBOL_GPL(__tcp_bpf_recvmsg);
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int tcp_bpf_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
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int nonblock, int flags, int *addr_len)
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{
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struct sk_psock *psock;
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int copied, ret;
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if (unlikely(flags & MSG_ERRQUEUE))
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return inet_recv_error(sk, msg, len, addr_len);
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if (!skb_queue_empty(&sk->sk_receive_queue))
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return tcp_recvmsg(sk, msg, len, nonblock, flags, addr_len);
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psock = sk_psock_get(sk);
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if (unlikely(!psock))
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return tcp_recvmsg(sk, msg, len, nonblock, flags, addr_len);
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lock_sock(sk);
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msg_bytes_ready:
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copied = __tcp_bpf_recvmsg(sk, psock, msg, len, flags);
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if (!copied) {
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int data, err = 0;
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long timeo;
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timeo = sock_rcvtimeo(sk, nonblock);
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data = tcp_bpf_wait_data(sk, psock, flags, timeo, &err);
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if (data) {
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if (skb_queue_empty(&sk->sk_receive_queue))
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goto msg_bytes_ready;
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release_sock(sk);
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sk_psock_put(sk, psock);
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return tcp_recvmsg(sk, msg, len, nonblock, flags, addr_len);
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}
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if (err) {
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ret = err;
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goto out;
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}
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copied = -EAGAIN;
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}
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ret = copied;
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out:
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release_sock(sk);
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sk_psock_put(sk, psock);
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return ret;
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}
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static int bpf_tcp_ingress(struct sock *sk, struct sk_psock *psock,
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struct sk_msg *msg, u32 apply_bytes, int flags)
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{
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bool apply = apply_bytes;
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struct scatterlist *sge;
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u32 size, copied = 0;
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struct sk_msg *tmp;
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int i, ret = 0;
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tmp = kzalloc(sizeof(*tmp), __GFP_NOWARN | GFP_KERNEL);
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if (unlikely(!tmp))
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return -ENOMEM;
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lock_sock(sk);
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tmp->sg.start = msg->sg.start;
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i = msg->sg.start;
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do {
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sge = sk_msg_elem(msg, i);
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size = (apply && apply_bytes < sge->length) ?
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apply_bytes : sge->length;
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if (!sk_wmem_schedule(sk, size)) {
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if (!copied)
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ret = -ENOMEM;
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break;
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}
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sk_mem_charge(sk, size);
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sk_msg_xfer(tmp, msg, i, size);
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copied += size;
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if (sge->length)
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get_page(sk_msg_page(tmp, i));
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sk_msg_iter_var_next(i);
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tmp->sg.end = i;
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if (apply) {
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apply_bytes -= size;
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if (!apply_bytes)
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break;
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}
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} while (i != msg->sg.end);
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if (!ret) {
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msg->sg.start = i;
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msg->sg.size -= apply_bytes;
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sk_psock_queue_msg(psock, tmp);
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sk_psock_data_ready(sk, psock);
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} else {
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sk_msg_free(sk, tmp);
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kfree(tmp);
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}
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release_sock(sk);
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return ret;
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}
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static int tcp_bpf_push(struct sock *sk, struct sk_msg *msg, u32 apply_bytes,
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int flags, bool uncharge)
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{
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bool apply = apply_bytes;
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struct scatterlist *sge;
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struct page *page;
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int size, ret = 0;
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u32 off;
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while (1) {
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bool has_tx_ulp;
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sge = sk_msg_elem(msg, msg->sg.start);
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size = (apply && apply_bytes < sge->length) ?
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apply_bytes : sge->length;
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off = sge->offset;
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page = sg_page(sge);
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tcp_rate_check_app_limited(sk);
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retry:
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has_tx_ulp = tls_sw_has_ctx_tx(sk);
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if (has_tx_ulp) {
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flags |= MSG_SENDPAGE_NOPOLICY;
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ret = kernel_sendpage_locked(sk,
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page, off, size, flags);
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} else {
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ret = do_tcp_sendpages(sk, page, off, size, flags);
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}
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if (ret <= 0)
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return ret;
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if (apply)
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apply_bytes -= ret;
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msg->sg.size -= ret;
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sge->offset += ret;
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sge->length -= ret;
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if (uncharge)
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sk_mem_uncharge(sk, ret);
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if (ret != size) {
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size -= ret;
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off += ret;
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goto retry;
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}
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if (!sge->length) {
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put_page(page);
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sk_msg_iter_next(msg, start);
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sg_init_table(sge, 1);
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if (msg->sg.start == msg->sg.end)
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break;
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}
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if (apply && !apply_bytes)
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break;
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}
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return 0;
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}
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static int tcp_bpf_push_locked(struct sock *sk, struct sk_msg *msg,
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u32 apply_bytes, int flags, bool uncharge)
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{
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int ret;
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lock_sock(sk);
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ret = tcp_bpf_push(sk, msg, apply_bytes, flags, uncharge);
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release_sock(sk);
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return ret;
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}
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int tcp_bpf_sendmsg_redir(struct sock *sk, struct sk_msg *msg,
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u32 bytes, int flags)
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{
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bool ingress = sk_msg_to_ingress(msg);
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struct sk_psock *psock = sk_psock_get(sk);
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int ret;
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if (unlikely(!psock)) {
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sk_msg_free(sk, msg);
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return 0;
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}
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ret = ingress ? bpf_tcp_ingress(sk, psock, msg, bytes, flags) :
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tcp_bpf_push_locked(sk, msg, bytes, flags, false);
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sk_psock_put(sk, psock);
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return ret;
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}
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EXPORT_SYMBOL_GPL(tcp_bpf_sendmsg_redir);
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static int tcp_bpf_send_verdict(struct sock *sk, struct sk_psock *psock,
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struct sk_msg *msg, int *copied, int flags)
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{
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bool cork = false, enospc = msg->sg.start == msg->sg.end;
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struct sock *sk_redir;
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u32 tosend, delta = 0;
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int ret;
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more_data:
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if (psock->eval == __SK_NONE) {
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/* Track delta in msg size to add/subtract it on SK_DROP from
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* returned to user copied size. This ensures user doesn't
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* get a positive return code with msg_cut_data and SK_DROP
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* verdict.
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*/
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delta = msg->sg.size;
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psock->eval = sk_psock_msg_verdict(sk, psock, msg);
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if (msg->sg.size < delta)
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delta -= msg->sg.size;
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else
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delta = 0;
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}
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if (msg->cork_bytes &&
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msg->cork_bytes > msg->sg.size && !enospc) {
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psock->cork_bytes = msg->cork_bytes - msg->sg.size;
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if (!psock->cork) {
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psock->cork = kzalloc(sizeof(*psock->cork),
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GFP_ATOMIC | __GFP_NOWARN);
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if (!psock->cork)
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return -ENOMEM;
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}
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memcpy(psock->cork, msg, sizeof(*msg));
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return 0;
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}
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tosend = msg->sg.size;
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if (psock->apply_bytes && psock->apply_bytes < tosend)
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tosend = psock->apply_bytes;
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switch (psock->eval) {
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case __SK_PASS:
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ret = tcp_bpf_push(sk, msg, tosend, flags, true);
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if (unlikely(ret)) {
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*copied -= sk_msg_free(sk, msg);
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break;
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}
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sk_msg_apply_bytes(psock, tosend);
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break;
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case __SK_REDIRECT:
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sk_redir = psock->sk_redir;
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sk_msg_apply_bytes(psock, tosend);
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if (psock->cork) {
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cork = true;
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psock->cork = NULL;
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}
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sk_msg_return(sk, msg, tosend);
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release_sock(sk);
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ret = tcp_bpf_sendmsg_redir(sk_redir, msg, tosend, flags);
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lock_sock(sk);
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if (unlikely(ret < 0)) {
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int free = sk_msg_free_nocharge(sk, msg);
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if (!cork)
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*copied -= free;
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}
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if (cork) {
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sk_msg_free(sk, msg);
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kfree(msg);
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msg = NULL;
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ret = 0;
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}
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break;
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case __SK_DROP:
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default:
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sk_msg_free_partial(sk, msg, tosend);
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sk_msg_apply_bytes(psock, tosend);
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*copied -= (tosend + delta);
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return -EACCES;
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}
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if (likely(!ret)) {
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if (!psock->apply_bytes) {
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psock->eval = __SK_NONE;
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if (psock->sk_redir) {
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sock_put(psock->sk_redir);
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psock->sk_redir = NULL;
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}
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}
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if (msg &&
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msg->sg.data[msg->sg.start].page_link &&
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msg->sg.data[msg->sg.start].length)
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goto more_data;
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}
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return ret;
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}
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static int tcp_bpf_sendmsg(struct sock *sk, struct msghdr *msg, size_t size)
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{
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struct sk_msg tmp, *msg_tx = NULL;
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int flags = msg->msg_flags | MSG_NO_SHARED_FRAGS;
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int copied = 0, err = 0;
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struct sk_psock *psock;
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long timeo;
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psock = sk_psock_get(sk);
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if (unlikely(!psock))
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return tcp_sendmsg(sk, msg, size);
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lock_sock(sk);
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timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT);
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while (msg_data_left(msg)) {
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bool enospc = false;
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u32 copy, osize;
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if (sk->sk_err) {
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err = -sk->sk_err;
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goto out_err;
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}
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copy = msg_data_left(msg);
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if (!sk_stream_memory_free(sk))
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goto wait_for_sndbuf;
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if (psock->cork) {
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msg_tx = psock->cork;
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} else {
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msg_tx = &tmp;
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sk_msg_init(msg_tx);
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}
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osize = msg_tx->sg.size;
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err = sk_msg_alloc(sk, msg_tx, msg_tx->sg.size + copy, msg_tx->sg.end - 1);
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if (err) {
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if (err != -ENOSPC)
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goto wait_for_memory;
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enospc = true;
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copy = msg_tx->sg.size - osize;
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}
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err = sk_msg_memcopy_from_iter(sk, &msg->msg_iter, msg_tx,
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copy);
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if (err < 0) {
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sk_msg_trim(sk, msg_tx, osize);
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goto out_err;
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}
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copied += copy;
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if (psock->cork_bytes) {
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if (size > psock->cork_bytes)
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psock->cork_bytes = 0;
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else
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psock->cork_bytes -= size;
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if (psock->cork_bytes && !enospc)
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goto out_err;
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/* All cork bytes are accounted, rerun the prog. */
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psock->eval = __SK_NONE;
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psock->cork_bytes = 0;
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}
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err = tcp_bpf_send_verdict(sk, psock, msg_tx, &copied, flags);
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if (unlikely(err < 0))
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goto out_err;
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continue;
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wait_for_sndbuf:
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set_bit(SOCK_NOSPACE, &sk->sk_socket->flags);
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wait_for_memory:
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err = sk_stream_wait_memory(sk, &timeo);
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if (err) {
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if (msg_tx && msg_tx != psock->cork)
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sk_msg_free(sk, msg_tx);
|
|
goto out_err;
|
|
}
|
|
}
|
|
out_err:
|
|
if (err < 0)
|
|
err = sk_stream_error(sk, msg->msg_flags, err);
|
|
release_sock(sk);
|
|
sk_psock_put(sk, psock);
|
|
return copied ? copied : err;
|
|
}
|
|
|
|
static int tcp_bpf_sendpage(struct sock *sk, struct page *page, int offset,
|
|
size_t size, int flags)
|
|
{
|
|
struct sk_msg tmp, *msg = NULL;
|
|
int err = 0, copied = 0;
|
|
struct sk_psock *psock;
|
|
bool enospc = false;
|
|
|
|
psock = sk_psock_get(sk);
|
|
if (unlikely(!psock))
|
|
return tcp_sendpage(sk, page, offset, size, flags);
|
|
|
|
lock_sock(sk);
|
|
if (psock->cork) {
|
|
msg = psock->cork;
|
|
} else {
|
|
msg = &tmp;
|
|
sk_msg_init(msg);
|
|
}
|
|
|
|
/* Catch case where ring is full and sendpage is stalled. */
|
|
if (unlikely(sk_msg_full(msg)))
|
|
goto out_err;
|
|
|
|
sk_msg_page_add(msg, page, size, offset);
|
|
sk_mem_charge(sk, size);
|
|
copied = size;
|
|
if (sk_msg_full(msg))
|
|
enospc = true;
|
|
if (psock->cork_bytes) {
|
|
if (size > psock->cork_bytes)
|
|
psock->cork_bytes = 0;
|
|
else
|
|
psock->cork_bytes -= size;
|
|
if (psock->cork_bytes && !enospc)
|
|
goto out_err;
|
|
/* All cork bytes are accounted, rerun the prog. */
|
|
psock->eval = __SK_NONE;
|
|
psock->cork_bytes = 0;
|
|
}
|
|
|
|
err = tcp_bpf_send_verdict(sk, psock, msg, &copied, flags);
|
|
out_err:
|
|
release_sock(sk);
|
|
sk_psock_put(sk, psock);
|
|
return copied ? copied : err;
|
|
}
|
|
|
|
static void tcp_bpf_remove(struct sock *sk, struct sk_psock *psock)
|
|
{
|
|
struct sk_psock_link *link;
|
|
|
|
sk_psock_cork_free(psock);
|
|
__sk_psock_purge_ingress_msg(psock);
|
|
while ((link = sk_psock_link_pop(psock))) {
|
|
sk_psock_unlink(sk, link);
|
|
sk_psock_free_link(link);
|
|
}
|
|
}
|
|
|
|
static void tcp_bpf_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;
|
|
tcp_bpf_remove(sk, psock);
|
|
rcu_read_unlock();
|
|
saved_unhash(sk);
|
|
}
|
|
|
|
static void tcp_bpf_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(sk);
|
|
if (unlikely(!psock)) {
|
|
rcu_read_unlock();
|
|
release_sock(sk);
|
|
return sk->sk_prot->close(sk, timeout);
|
|
}
|
|
|
|
saved_close = psock->saved_close;
|
|
tcp_bpf_remove(sk, psock);
|
|
rcu_read_unlock();
|
|
release_sock(sk);
|
|
saved_close(sk, timeout);
|
|
}
|
|
|
|
enum {
|
|
TCP_BPF_IPV4,
|
|
TCP_BPF_IPV6,
|
|
TCP_BPF_NUM_PROTS,
|
|
};
|
|
|
|
enum {
|
|
TCP_BPF_BASE,
|
|
TCP_BPF_TX,
|
|
TCP_BPF_NUM_CFGS,
|
|
};
|
|
|
|
static struct proto *tcpv6_prot_saved __read_mostly;
|
|
static DEFINE_SPINLOCK(tcpv6_prot_lock);
|
|
static struct proto tcp_bpf_prots[TCP_BPF_NUM_PROTS][TCP_BPF_NUM_CFGS];
|
|
|
|
static void tcp_bpf_rebuild_protos(struct proto prot[TCP_BPF_NUM_CFGS],
|
|
struct proto *base)
|
|
{
|
|
prot[TCP_BPF_BASE] = *base;
|
|
prot[TCP_BPF_BASE].unhash = tcp_bpf_unhash;
|
|
prot[TCP_BPF_BASE].close = tcp_bpf_close;
|
|
prot[TCP_BPF_BASE].recvmsg = tcp_bpf_recvmsg;
|
|
prot[TCP_BPF_BASE].stream_memory_read = tcp_bpf_stream_read;
|
|
|
|
prot[TCP_BPF_TX] = prot[TCP_BPF_BASE];
|
|
prot[TCP_BPF_TX].sendmsg = tcp_bpf_sendmsg;
|
|
prot[TCP_BPF_TX].sendpage = tcp_bpf_sendpage;
|
|
}
|
|
|
|
static void tcp_bpf_check_v6_needs_rebuild(struct sock *sk, struct proto *ops)
|
|
{
|
|
if (sk->sk_family == AF_INET6 &&
|
|
unlikely(ops != smp_load_acquire(&tcpv6_prot_saved))) {
|
|
spin_lock_bh(&tcpv6_prot_lock);
|
|
if (likely(ops != tcpv6_prot_saved)) {
|
|
tcp_bpf_rebuild_protos(tcp_bpf_prots[TCP_BPF_IPV6], ops);
|
|
smp_store_release(&tcpv6_prot_saved, ops);
|
|
}
|
|
spin_unlock_bh(&tcpv6_prot_lock);
|
|
}
|
|
}
|
|
|
|
static int __init tcp_bpf_v4_build_proto(void)
|
|
{
|
|
tcp_bpf_rebuild_protos(tcp_bpf_prots[TCP_BPF_IPV4], &tcp_prot);
|
|
return 0;
|
|
}
|
|
core_initcall(tcp_bpf_v4_build_proto);
|
|
|
|
static void tcp_bpf_update_sk_prot(struct sock *sk, struct sk_psock *psock)
|
|
{
|
|
int family = sk->sk_family == AF_INET6 ? TCP_BPF_IPV6 : TCP_BPF_IPV4;
|
|
int config = psock->progs.msg_parser ? TCP_BPF_TX : TCP_BPF_BASE;
|
|
|
|
sk_psock_update_proto(sk, psock, &tcp_bpf_prots[family][config]);
|
|
}
|
|
|
|
static void tcp_bpf_reinit_sk_prot(struct sock *sk, struct sk_psock *psock)
|
|
{
|
|
int family = sk->sk_family == AF_INET6 ? TCP_BPF_IPV6 : TCP_BPF_IPV4;
|
|
int config = psock->progs.msg_parser ? TCP_BPF_TX : TCP_BPF_BASE;
|
|
|
|
/* Reinit occurs when program types change e.g. TCP_BPF_TX is removed
|
|
* or added requiring sk_prot hook updates. We keep original saved
|
|
* hooks in this case.
|
|
*/
|
|
sk->sk_prot = &tcp_bpf_prots[family][config];
|
|
}
|
|
|
|
static int tcp_bpf_assert_proto_ops(struct proto *ops)
|
|
{
|
|
/* In order to avoid retpoline, we make assumptions when we call
|
|
* into ops if e.g. a psock is not present. Make sure they are
|
|
* indeed valid assumptions.
|
|
*/
|
|
return ops->recvmsg == tcp_recvmsg &&
|
|
ops->sendmsg == tcp_sendmsg &&
|
|
ops->sendpage == tcp_sendpage ? 0 : -ENOTSUPP;
|
|
}
|
|
|
|
void tcp_bpf_reinit(struct sock *sk)
|
|
{
|
|
struct sk_psock *psock;
|
|
|
|
sock_owned_by_me(sk);
|
|
|
|
rcu_read_lock();
|
|
psock = sk_psock(sk);
|
|
tcp_bpf_reinit_sk_prot(sk, psock);
|
|
rcu_read_unlock();
|
|
}
|
|
|
|
int tcp_bpf_init(struct sock *sk)
|
|
{
|
|
struct proto *ops = READ_ONCE(sk->sk_prot);
|
|
struct sk_psock *psock;
|
|
|
|
sock_owned_by_me(sk);
|
|
|
|
rcu_read_lock();
|
|
psock = sk_psock(sk);
|
|
if (unlikely(!psock || psock->sk_proto ||
|
|
tcp_bpf_assert_proto_ops(ops))) {
|
|
rcu_read_unlock();
|
|
return -EINVAL;
|
|
}
|
|
tcp_bpf_check_v6_needs_rebuild(sk, ops);
|
|
tcp_bpf_update_sk_prot(sk, psock);
|
|
rcu_read_unlock();
|
|
return 0;
|
|
}
|