Opened 4 years ago

Closed 9 months ago

Last modified 4 weeks ago

#13575 closed defect (fixed)

Disable randomised Firefox HTTP cache decay user test groups

Reported by: isis Owned by: tbb-team
Priority: Medium Milestone:
Component: Applications/Tor Browser Version:
Severity: Normal Keywords: tbb-pref, tbb-fingerprinting, ff52-esr, tbb-easy, TorBrowserTeam201801R
Cc: isis Actual Points:
Parent ID: Points:
Reviewer: Sponsor:

Description

I need to look into it more, but I think we should be setting browser.cache.frecency_experiment to -1 to disable HTTP_CACHE_MISS_HALFLIFE_EXPERIMENT. Since we have Telemetry disabled, of course, Mozilla's experiment shouldn't be collecting any data on our users. However, if that pref is not set in firefox.js to -1, it will default to 0. And if it's 0, then it's randomised between 1 and 4 inclusive, setting different HTTP cache decay times for the four groups, which might make for a bit of a rough-edged fingerprinting mechanism.

Child Tickets

Attachments (2)

Change History (13)

comment:1 Changed 2 years ago by bugzilla

Severity: Normal

Mozilla continues its experiment, now with sub-hour resolution: https://bugzilla.mozilla.org/show_bug.cgi?id=1098422

comment:2 Changed 19 months ago by cypherpunks

Keywords: ff52-esr added

We don't need any experiments active in Tor Browser.

comment:3 in reply to:  description Changed 13 months ago by cypherpunks

Status: newneeds_review

we should be setting browser.cache.frecency_experiment to -1

to fix this ticket without patching.

comment:4 Changed 13 months ago by gk

Status: needs_reviewassigned

Thanks for contributing. We use needs_review for tickets that have patches attached we can reason about and merge if we think they are okay. I am happy to consider a patch to get this ticket moved forward. So, if you could attach one or point to some commit in a (preferably) git repository that would be great.

comment:5 in reply to:  4 Changed 13 months ago by cypherpunks

Keywords: tbb-easy added

Replying to gk:

Thanks for contributing.

Thank you too. We made a great progress for the last several years. So, glad to hear it from you.

We use needs_review for tickets that have patches attached we can reason about and merge if we think they are okay.

needs_review was used to show that thorough code analysis didn't reveal anything wrong with the proposed solution, and it can be merged as is.

I am happy to consider a patch to get this ticket moved forward.

Sure, but no one added it during 3 years, for some reason.

So, if you could attach one or point to some commit in a (preferably) git repository that would be great.

It is so easy that it's better suited as an exercise for new job applicants.

comment:6 Changed 9 months ago by ffmancera

Status: assignedneeds_review

Here is a patch, I did the changes in 000-tor-browser.js instead of firefox.js. If it is wrong, please let me know.

Last edited 9 months ago by ffmancera (previous) (diff)

comment:7 Changed 9 months ago by gk

Keywords: TorBrowserTeam201801R added

comment:8 Changed 9 months ago by gk

Resolution: fixed
Status: needs_reviewclosed

Thanks, applied to tor-browser-52.6.0esr-8.0-2 (commit f6d6512bf85d964fa5a470f2528042c527523a34).

comment:9 Changed 6 months ago by cypherpunks

Keywords: tbb-backport added

comment:11 Changed 4 weeks ago by gk

Keywords: tbb-backport removed
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