public inbox for bpf@vger.kernel.org
 help / color / mirror / Atom feed
From: Jakub Sitnicki <jakub@cloudflare.com>
To: Cong Wang <xiyou.wangcong@gmail.com>
Cc: 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>,
	John Fastabend <john.fastabend@gmail.com>,
	Lorenz Bauer <lmb@cloudflare.com>
Subject: Re: [Patch bpf v2] skmsg: check sk_rcvbuf limit before queuing to ingress_skb
Date: Thu, 01 Jul 2021 17:56:12 +0200	[thread overview]
Message-ID: <877diarpsz.fsf@cloudflare.com> (raw)
In-Reply-To: <20210701061656.34150-1-xiyou.wangcong@gmail.com>

On Thu, Jul 01, 2021 at 08:16 AM CEST, Cong Wang wrote:
> From: Cong Wang <cong.wang@bytedance.com>
>
> Jiang observed OOM frequently when testing our AF_UNIX/UDP
> proxy. This is due to the fact that we do not actually limit
> the socket memory before queueing skb to ingress_skb. We
> charge the skb memory later when handling the psock backlog,
> but it is not limited either.
>
> This patch adds checks for sk->sk_rcvbuf right before queuing
> to ingress_skb and drops packets if this limit exceeds. This
> is very similar to UDP receive path. Ideally we should set the
> skb owner before this check too, but it is hard to make TCP
> happy about sk_forward_alloc.
>
> Reported-by: Jiang Wang <jiang.wang@bytedance.com>
> Cc: Daniel Borkmann <daniel@iogearbox.net>
> Cc: John Fastabend <john.fastabend@gmail.com>
> Cc: Lorenz Bauer <lmb@cloudflare.com>
> Cc: Jakub Sitnicki <jakub@cloudflare.com>
> Signed-off-by: Cong Wang <cong.wang@bytedance.com>
> ---

Acked-by: Jakub Sitnicki <jakub@cloudflare.com>

By saying that it is hard to make TCP happy about sk_forward_alloc, I'm
guessing you're referring to problems described in 144748eb0c44 ("bpf,
sockmap: Fix incorrect fwd_alloc accounting") [1]?

Thanks for the fix.

[1] https://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux.git/commit/?id=144748eb0c445091466c9b741ebd0bfcc5914f3d

[...]

  reply	other threads:[~2021-07-01 15:56 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 [this message]
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
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=877diarpsz.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