bpf.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Jakub Sitnicki <jakub@cloudflare.com>
To: John Fastabend <john.fastabend@gmail.com>
Cc: Cong Wang <xiyou.wangcong@gmail.com>,
	netdev@vger.kernel.org, bpf@vger.kernel.org,
	Cong Wang <cong.wang@bytedance.com>,
	Jiang Wang <jiang.wang@bytedance.com>,
	Daniel Borkmann <daniel@iogearbox.net>,
	"Lorenz Bauer" <lmb@cloudflare.com>
Subject: Re: [Patch bpf v2] skmsg: check sk_rcvbuf limit before queuing to ingress_skb
Date: Sun, 04 Jul 2021 15:10:28 +0200	[thread overview]
Message-ID: <874kdarzqz.fsf@cloudflare.com> (raw)
In-Reply-To: <875yxrs2sc.fsf@cloudflare.com>

On Sat, Jul 03, 2021 at 07:52 PM CEST, Jakub Sitnicki wrote:

[...]

> Then there is the case when a parser prog is attached. In this case the
> skb is really gone if we drop it on redirect.
>
> In sk_psock_strp_read, we ignore the -EIO error from
> sk_psock_verdict_apply, and return to tcp_read_sock how many bytes have
> been parsed.
>
>   sk->sk_data_ready
>     sk_psock_verdict_data_ready
>       ->read_sock(..., sk_psock_verdict_recv)
>         tcp_read_sock (used = copied = eaten)
>           strp_recv -> ret = eaten
>             __strp_recv -> ret = eaten
>               strp->cb.rcv_msg -> -EIO
>                 sk_psock_verdict_apply -> -EIO
>                   sk_psock_redirect -> -EIO

Copy-paste error. The call chain for the parser case goes as so:

  sk->sk_data_ready
    sk_psock_strp_data_ready
      strp_data_ready
        strp_read_sock
          ->read_sock(..., strp_recv)
            tcp_read_sock (used = copied = skb->len)
              strp_recv -> ret = skb->len
                __strp_recv -> ret = skb->len (dummy parser case)
                  strp->cb.rcv_msg -> -EIO
                    sk_psock_verdict_apply -> -EIO
                      sk_psock_redirect -> -EIO

  reply	other threads:[~2021-07-04 13:10 UTC|newest]

Thread overview: 11+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2021-07-01  6:16 [Patch bpf v2] skmsg: check sk_rcvbuf limit before queuing to ingress_skb Cong Wang
2021-07-01 15:56 ` Jakub Sitnicki
2021-07-01 16:26   ` John Fastabend
2021-07-01 16:23 ` John Fastabend
2021-07-01 18:00   ` Cong Wang
2021-07-02 19:33     ` Cong Wang
2021-07-03 17:52   ` Jakub Sitnicki
2021-07-04 13:10     ` Jakub Sitnicki [this message]
2021-07-04 19:53     ` Cong Wang
2021-07-05  8:24       ` Jakub Sitnicki
2021-07-05 16:24         ` John Fastabend

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=874kdarzqz.fsf@cloudflare.com \
    --to=jakub@cloudflare.com \
    --cc=bpf@vger.kernel.org \
    --cc=cong.wang@bytedance.com \
    --cc=daniel@iogearbox.net \
    --cc=jiang.wang@bytedance.com \
    --cc=john.fastabend@gmail.com \
    --cc=lmb@cloudflare.com \
    --cc=netdev@vger.kernel.org \
    --cc=xiyou.wangcong@gmail.com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).