WSL2: Do not recieve UDP packets from network interface using mirrored option

[mgkbeer]

Windows Version

10.0.22621.3007

WSL Version

2.1.0.0

Are you using WSL 1 or WSL 2?

• WSL 2
• WSL 1

Kernel Version

5.15.137.3-1

Distro Version

Ubuntu 22.04

Other Software

No response

Repro Steps

.wslconfig
[wsl2]
networkingMode=mirrored
[experimental] firewall=true

I run iperf client on WSL2 Ubuntu against server running on another device connected thru eth0
iperf -u -c 169.254.1.10
eth0: flags=4163<UP,BROADCAST,RUNNING,MULTICAST> mtu 9000
inet 169.254.1.100 netmask 255.255.255.0 broadcast 169.254.1.255
inet6 fe80::ae4c:1e49:3c20:1ded prefixlen 64 scopeid 0x20
ether 00:e0:4c:68:00:17 txqueuelen 1000 (Ethernet)
RX packets 4 bytes 380 (380.0 B)
RX errors 0 dropped 0 overruns 0 frame 0
TX packets 23 bytes 3628 (3.6 KB)
TX errors 0 dropped 0 overruns 0 carrier 0 collisions 0
and it works, however, when I run client on that external device I do not see any packets coming to WSL
I also tried adding new rules to firewall allowing specific port to be allowed, disabling firewalls (mcafee and windows) but for no avail

Expected Behavior

Expected behavior is that I get all the UDP packets on WSL2 that sent on that interface

Actual Behavior

I do not see any UDP packets when external device sending those to port 5001 and address 169.254.1.100

Diagnostic Logs

WslNetworkingLogs-2024-01-15_12-25-16.zip

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• Question on UDP multicast in mirrored mode and Wireshark (#10735), similarity score: 0.72
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[pmartincic]

This looks similar to #11034, are you using the experimental hostAddressLoopback config option?

[mgkbeer]

This looks similar to #11034, are you using the experimental hostAddressLoopback config option?
No, I did not use hostAddressLoopback option
.wslconfig
[wsl2]
networkingMode=mirrored
[experimental] firewall=true

[pmartincic]

By default mirrored mirrors binds that would capture 127.0.0.1 unless using that experimental config option. If you use that option and it still doesn't work then chime in on bug #11034

[mgkbeer]

I tried adding that option but it did not change anything, I still do not receive any packets on eth0 169.254.1.100
Did you have a chance to look at attached logs? I frankly do not believe those two issues are related
[wsl2]
networkingMode = mirrored
firewall=true
localhostforwarding = true
[experimental]
hostAddressLoopback = true
Interesting thing I want to mention is that it works from time to time, but when it works Jumbo frames do not work - only frames up to 1500. Is there a need to set MTU for a switch?