netdev.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Stephen Suryaputra <ssuryaextr@gmail.com>
To: David Ahern <dsahern@gmail.com>
Cc: netdev@vger.kernel.org
Subject: Re: Matching unbound sockets for VRF
Date: Sun, 27 Mar 2022 08:57:38 -0400	[thread overview]
Message-ID: <YkBfQqz66FxYmGVV@ssuryadesk> (raw)
In-Reply-To: <7b5eb495-a3fe-843f-9020-0268fb681c72@gmail.com>

[-- Attachment #1: Type: text/plain, Size: 1860 bytes --]

On Fri, Mar 25, 2022 at 08:13:55AM -0600, David Ahern wrote:
> On 3/24/22 11:19 AM, Stephen Suryaputra wrote:
> > Hello,
> > 
> > After upgrading to a kernel version that has commit 3c82a21f4320c ("net:
> > allow binding socket in a VRF when there's an unbound socket") several
> > of our applications don't work anymore. We are relying on the previous
> > behavior, i.e. when packets arrive on an l3mdev enslaved device, the
> > unbound sockets are matched.
> > 
> > I understand the use case for the commit but given that the previous
> > behavior has been there for quite some time since the VRF introduction,
> > should there be a configurable option to get the previous behavior? The
> > option could be having the default be the behavior achieved by the
> > commit.
> > 
> 
> I thought the behavior was controlled by the l3mdev sysctl knobs.

The addresses for Mike and Robert bounced. So, removing them from the
thread.

The problem is that our system uses a fallback rule to a vrf, e.g.:

1000:   from all lookup [l3mdev-table]
32765:  from all lookup local
32766:  from all lookup main
32767:  from all lookup default
32768:  from all lookup 256

to force traffic to go out of the vrf-enslaved interface. When the host
with the vrf initiates tcp connection, the received SYN+ACK fails to
find a matching socket after the commit. See the traffic dump:

08:51:28.625806 IP 10.1.1.1.48076 > 10.1.1.2.1499: Flags [S], seq 2060777757, win 64240, options [mss 1460,sackOK,TS val 3307983770 ecr 0,nop,wscale 7], length 0
08:51:28.625831 IP 10.1.1.2.1499 > 10.1.1.1.48076: Flags [S.], seq 4017990855, ack 2060777758, win 65160, options [mss 1460,sackOK,TS val 1658979570 ecr 3307983770,nop,wscale 7], length 0
08:51:28.625837 IP 10.1.1.1.48076 > 10.1.1.2.1499: Flags [R], seq 2060777758, win 0, length 0

The reproducer script is attached.

Thanks,

Stephen.

[-- Attachment #2: socket.sh --]
[-- Type: application/x-sh, Size: 1721 bytes --]

  reply	other threads:[~2022-03-27 12:57 UTC|newest]

Thread overview: 7+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-03-24 17:19 Matching unbound sockets for VRF Stephen Suryaputra
2022-03-25 14:13 ` David Ahern
2022-03-27 12:57   ` Stephen Suryaputra [this message]
2022-04-03 16:24     ` David Ahern
2022-04-04 12:41       ` Stephen Suryaputra
2022-04-05 14:32         ` David Ahern
2022-04-07 21:28           ` Ben Greear

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=YkBfQqz66FxYmGVV@ssuryadesk \
    --to=ssuryaextr@gmail.com \
    --cc=dsahern@gmail.com \
    --cc=netdev@vger.kernel.org \
    /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).