Port filter blocks my own IP when using "Disallow connection to peers on proveleged ports"

[sakkamade]

qBittorrent version and Operating System

qBittorrent 4.3.0.1, Windows 10 1903

What is the problem

In the log of blocked IPs I can see my own IP more frequently than once per minute:
24/11/2020 8:30 - **.**.**.*** was blocked. Reason: port filter.

What can be a reason for this?

What is the expected behavior

Not seeing my own IP there, I guess.

Steps to reproduce

Turn on Disallow connection to peers on proveleged ports.

Extra info(if any)

It's doesn't depend whether Windows Defender turned off or on.
Using only Windows Firewall.
Port is always 5-digits.
Availing myself of no proxy/VPN.
Within router settings the each of the ports (internal and external of UDP and TCP) are forwarded by UPnP just fine, leastwise seeming to.

[Seeker2]

It's a loopback somewhere. Usually involves a router and/or multiple IP addresses to have this happen normally.

The problem can possibly be traced back to qBitTorrent not knowing its own IP address, so when it's fed that IP address from PEX (Peer EXchange) or DHT...qBT attempts to connect to it and then you see the Port filter blocking your own IP.

At least that's one way your problem can happen...no doubt there's others which may be bug-related instead of "weird" networking.

Disallow connection to peers on privileged ports ...means qBT "sees" the connection attempt as though it was on a "low" port number (less than 1000?)...but that shouldn't be happening because you also added:
"Port is always 5-digits."
That's still a possibility if the outgoing port number isn't the same as the incoming port number. If the networking traffic goes through a filter, it's possible the source port number gets changed at least as it's perceived by the destination. (Such as with "imperfect" proxy servers.)
Either that or qBT sees the incoming connection originating from 0.0.0.0 or 127.0.0.1 or something and blocks that ...incorrectly stating the reason for the block was "peers on privileged ports".

[sakkamade]

Just fancy to denote that perfectly equal issue I experience on Linux as well—Manjaro, to be precise—the cause, thus, is everything but Windows.

[sakkamade]

I guess this issue is the result of #10791, hence is the duplicate.
Since I am also seeing my own IP in the peers list.