Regression from iptables has been introduced

[ctolkien]

tailscale/tailscale#13863

This issue is impacting users of Tailscale, and it seems the problem patch was rolled out to azure-linux approx 1 week ago.

[anphel31]

Can you point to the specific patch that could have caused this regression?

[raggi]

regression: torvalds/linux@0bfcb7b
fix: torvalds/linux@306ed17

[raggi]

this is a firewall regression, it's essentially a 0-day that was backported by a bunch of distros to kernel versions where it was never applied upstream.