> On 15. Apr 2022, at 23:39, Florian Smeets <f...@smeets.xyz> wrote: > > On 15.04.22 21:24, tue...@freebsd.org wrote: >>> On 15. Apr 2022, at 20:20, Florian Smeets <f...@smeets.xyz> wrote: >>> >>> >>> Hi, >>> >>> there seems to be an issue with local IPv6 TCP connections on main. I have >>> been seeing this for a couple of months at least. pkg upgr on my webserver >>> hosting the pkg repo is very slow, all other hosts can connect to the pkg >>> repo just fine. So IPv6 connections from external hosts are not affected. >>> >>> I thought I must have misconfigured something, as my setup is a bit weird. >>> Yesterday I noticed the same issue on a different host, turns out all my >>> 14.0 hosts seem to be affected, cognet@ could also reproduce it on one of >>> his systems. >>> >>> The service/software used does not seem to matter, I tried with port 22, >>> 25, 80 and 443. >>> >>> ICMP and UDP don't seem to be affected. ping6 gets replies immediately. And >>> UDP connections with nc -l -u / nc -u don't have any delay, sent data is >>> received immediately. >>> >>> Testing local TCP connections show this: >>> >>> flo@rp64:~ $ ifconfig dwc0|grep 2003 >>> inet6 2003:cf:df49:c97:4c59:ebff:fec1:463d prefixlen 64 autoconf >>> flo@rp64:~ $ nc -v 2003:cf:df49:c97:4c59:ebff:fec1:463d 22 >>> [3 second delay here] >>> Connection to 2003:cf:df49:c97:4c59:ebff:fec1:463d 22 port [tcp/ssh] >>> succeeded! >>> SSH-2.0-OpenSSH_8.9 FreeBSD-20220413 >>> > >>> >>> I need help debugging this, I don't know how to analyze this further. I >>> will start bisecting this, but I thought maybe someone has an idea. >> Hi Florian, >> I can reproduce this locally, will try to figure out what is going on. If >> you can bisect it, it would be great. > > Found the culprit 1817be481b8703ae86730b151a6f49cc3022930f. And indeed > toggling net.inet6.ip6.source_address_validation makes the issue go away on > latest main. Cool, thanks for providing the information. However, I don't understand why results in dropping the first two SYN segments (this should not happen) and why the third is accepted (they should all treated the same).
Best regards Michael > > Florian > <OpenPGP_0xEF5BA4DCD5A9F3C0.asc>
