1741955 - DoH. "network.trr.mode" pref reverts to 2

Status: VERIFIED FIXED

(Core :: Networking: DNS, defect, P3)

Description

[Leon]

User Agent: Mozilla/5.0 (Windows NT 10.0; Win64; x64; rv:94.0) Gecko/20100101 Firefox/94.0

Steps to reproduce:

1. Navigate to "about:config" page and set the "network.trr.mode" pref to 3
2. Change the DoH provider from settings

Actual results:

The value of the pref changes to 2.

Expected results:

The value of the pref remains set to "3".

Comment 1

[Leon]

Such behavior can provoke DNS leaks.

Also if the "network.trr.mode" is locked to 3 via policies.json, then it's impossible to change the DoH provider from settings' page, the options is grayed out, which is also quite strange.

Comment 2

[BugBot [:suhaib / :marco/ :calixte]]

The Bugbug bot thinks this bug should belong to the 'Firefox::Security' component, and is moving the bug to that component. Please revert this change in case you think the bot is wrong.

Comment 3

[Jeronimo Torti (Please send NI request to Brindusa Tot)]

Hi Leon,
thank you for taking the time to submit this bug report.
I was able to reproduce on Windows 10, on Firefox Nightly 96.0a1 (2021-11-19) (64-bit) version and Release 94.0.1 (64-bit) version, in the same way as described in steps. I set the flags and severity accordingly.

I let the assigned component in order to get the dev team involved, but if it's not relevant,
'Firefox-Security' team, please feel free to change the component if this is not the appropriate one.
Thanks,
Jerónimo.

Comment 4

[Leon]

Will it be ever fixed?

Comment 5

[Leon]

soon it will be 1 year, nobody cares

Comment 6

[Kershaw Chang [:kershaw]]

This should be easy to fix. We just need to check the current value here.

Comment 7

[Marc Leclair [:mleclair]]

Attachment: Bug 1741955: allow value set through about:config for trr mode to precede about:pref r=kershaw

Comment 8

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/400c7fe6d80a
allow value set through about:config for  trr mode to precede about:pref r=kershaw,pbz

Comment 9

[Cristian Tuns]

https://hg.mozilla.org/mozilla-central/rev/400c7fe6d80a

Comment 10

[Anca Soncutean, Desktop QA]

Reproduced with Fx 96.0a1 (2021-11-18) on Windows 10.
Verified fixed with Fx 109.0a1 (2022-11-23) on Windows 10, Ubuntu 22.04 and macOS 12.