Bug#1024070: linux-image-6.0.0-3-amd64: IPv6 ProxyNDP stops responding to ND solicitation some time after startup

[Salvatore Bonaccorso <carnil@debian.org>]

Control: tags -1 + moreinfo

Hi,

On Mon, Nov 14, 2022 at 06:34:43AM -0500, Kevin P. Fleming wrote:
> Package: src:linux
> Version: 6.0.7-1
> Severity: normal
> Tags: ipv6
> 
> Dear Maintainer,
> 
> This system has been operating for most of the last 12 months, using
> ProxyNDP on its external interface for eight addresses. After
> upgrading to the 6.0 kernel series, the kernel stops responding to ND
> solicitations for those addresses after startup... it does not happen
> immediately, but reliably occurs. When the system is in this state
> (not responding to ND solicitations for the proxy addresses), the
> proxy addresses are still shown in 'ip neigh show proxy', and the
> single non-proxy address on the same interface continues operating
> normally.
> 
> Booting the system with the 5.19.0-2 kernel package cures the problem,
> with no other changes.
> 
> Example output:
> 
> root@net22:~# ip neigh show proxy
> 2607:5300:203:9743::1 dev ve-diw20 proxy 
> 2607:5300:203:9743::1 dev ve-matrix20 proxy 
> 2607:5300:203:9743::1 dev ve-ns3 proxy 
> 2607:5300:203:9743::1 dev ve-ldl20 proxy 
> 2607:5300:203:9743::1 dev ve-quassel21 proxy 
> 2607:5300:203:9743::1 dev ve-mastodon22 proxy 
> 2607:5300:203:9743::1 dev ve-monica21 proxy 
> 2607:5300:203:9743::1 dev ve-mail20 proxy 
> 2607:5300:203:9743:4::1 dev enp1s0f0 proxy 
> 2607:5300:203:9743:1::1 dev enp1s0f0 proxy 
> 2607:5300:203:9743:8::1 dev enp1s0f0 proxy 
> 2607:5300:203:9743:5::1 dev enp1s0f0 proxy 
> 2607:5300:203:9743:3::1 dev enp1s0f0 proxy 
> 2607:5300:203:9743:2::1 dev enp1s0f0 proxy 
> 2607:5300:203:9743:6::1 dev enp1s0f0 proxy 
> 2607:5300:203:9743:7::1 dev enp1s0f0 proxy 
> 
> The addresses on enp1s0f0 are the ones which stop responding.

Does the following matches your problem?

https://lore.kernel.org/netdev/Y295+9+JDjqRWbwU@x1.ze-it.at/

Would you be able to test the mentioned patch to verify a fix for your
issue? The above changes fixes 0ff4eb3d5ebb ("neighbour: make
proxy_queue.qlen limit per-device") introduced in 6.0-rc2.

Regards,
Salvatore