1640822 - FF on Linux mistake IPv6 address sometimes/often between tabs

Status: RESOLVED DUPLICATE of bug 1420777

(Core :: Networking, defect)

Description

[patrick]

Attachment: Screenshot_20200526_102115.png

User Agent: Mozilla/5.0 (X11; Linux x86_64; rv:76.0) Gecko/20100101 Firefox/76.0

Steps to reproduce:

Hi,
our network has more about 100 users, but only with Firefox on Linux (from Debian packages installed or vanilla from your site as in my case) with a full dual stack network firefox behaves curious..:

I have opened some more tabs, also this three sites:

bcs.int.leonex.de has IPv6 address 2001:678:4a8:500::bc:5
pws.int.leonex.de has IPv6 address 2001:678:4a8:500:0:face:bad:c0de
ticket.int.leonex.de has IPv6 address 2001:678:4a8:500:0:3:1337:1

While working with this three sites on a refresh, action or an ajax call it happens, that firefox mistakes the connecting IP address from the other tab. So if I surf on https://bcs.int.leonex.de/ and doing something it connects e.g. to 2001:678:4a8:500:0:3:1337:1 instead of 2001:678:4a8:500::bc:5, which results in an error, like 404. If I switch the tab to the other one, same result could happen, e.g. it connects to 2001:678:4a8:500:0:face:bad:c0de instead of 2001:678:4a8:500:0:3:1337:1

If I do a refresh / strg+f5 it connects again to the correct url.
I also had that about one year ago with Firefox (installed from Debian), but didn't debugged it. Now with a fresh install and Firefox installed from your site I made some checks.
If I install the flagflox plugin, I also can see in flagfox, that firefox used the wrong IP.
Using chromium and other browsers on the same system: I can't reproduce it.

Also if I write this in my /etc/hosts, firefox is sometimes confused:

2001:678:4a8:500::bc:5 bcs.int.leonex.de
2001:678:4a8:500:0:face:bad:c0de pws.int.leonex.de
2001:678:4a8:500:0:3:1337:1 ticket.int.leonex.de

I also installed a local bind9 server with full query debugging: there wasn't any wrong result.

Comment 1

[Clara Guerrero ( Need Info Brindusa Tot Please)]

Hi Patrick,

Thanks for the details. I will move this over to a component so developers can take a look over it. If is not the correct component please feel free to change it to an appropriate one.
Best,

Clara

Comment 2

[Valentin Gosu [:valentin] (he/him)]

This sounds a lot like bug 1420777.
@Patrick, you can verify it that's the case by disabling HTTP2 and see if it still happens.
Bug 1420777 should be fixed soon.