Re: [PATCH net-next v2] ipv6: Add NETCONFA_FORCE_FORWARDING to netconf messages

[Gabriel Goller <g.goller@proxmox.com>]

On 09.11.2026 11:05, Ido Schimmel wrote:
> On Wed, Nov 04, 2026 at 10:46:10AM +0100, Gabriel Goller wrote:
> > Since force_forwarding was added, changing the sysctl sends an
> > RTM_NEWNETCONF notification of type NETCONFA_FORCE_FORWARDING, but
> > inet6_netconf_fill_devconf() never emits the attribute. Listeners only
> > receive NETCONFA_IFINDEX without the new value, and RTM_GETNETCONF
> > replies and dumps omit it as well.
> > 
> > Also send a notification when disabling all.forwarding resets
> > force_forwarding on an interface, which previously happened silently.
> > 
> > Fixes: f24987ef6959 ("ipv6: add `force_forwarding` sysctl to enable per-interface forwarding")
> 
> Fixes tag on net-next is only valid when the blamed commit is only in
> net-next, but maybe Paolo / Jakub will agree to strip it, so wait with
> v3.
> 
> > Signed-off-by: Gabriel Goller <g.goller@proxmox.com>
> 
> Reviewed-by: Ido Schimmel <idosch@nvidia.com>
> 
> There's a report from Sashiko [1] about a pre-existing issue:
> all.force_forwarding not being cleared when all.forwarding is cleared.
> 
> # ip link add name dummy1 type dummy
> # sysctl -wq net.ipv6.conf.all.forwarding=1
> # sysctl -wq net.ipv6.conf.all.force_forwarding=1
> # sysctl -wq net.ipv6.conf.all.forwarding=0
> # sysctl net.ipv6.conf.dummy1.force_forwarding
> net.ipv6.conf.dummy1.force_forwarding = 0
> # sysctl net.ipv6.conf.all.force_forwarding
> net.ipv6.conf.all.force_forwarding = 1
> 
> [1] https://netdev-ai.bots.linux.dev/sashiko/#/patchset/20261104-ipv6_add_netconfa-v2-1-6f660990062f@proxmox.com

Thanks, sent a patch:

https://lore.kernel.org/netdev/20261109-ipv6_reset_all-v1-1-815dfd508246@proxmox.com/

Gabriel