1193712 - Clearing Private Data does not log user out of sites

Status: RESOLVED FIXED

(Firefox for iOS :: General, defect)

Description

[Aaron Train [:aaronmt]]

https://groups.google.com/a/mozilla.com/d/msgid/ios-feedback/1439372146.460776474%40f10.my.com?utm_medium=email&utm_source=footer

Visit Twitter, sign-in, clear private-data, visit Twitter -> signed-in

https://github.com/mozilla/firefox-ios/blob/master/Client/Frontend/Settings/Clearables.swift

Comment 1

[Aaron Train [:aaronmt]]

different workarounds http://stackoverflow.com/questions/31289838/how-to-delete-wkwebview-cookies

Comment 2

[Aaron Train [:aaronmt]]

also found http://www.openradar.me/20417093

Comment 3

[Aaron Train [:aaronmt]]

After clearing private data my container does not contain a Cookies.binarycookies file, where prior it was available and parsing it shows a large number of Twitter and related auth cookies

Comment 4

[Stefan Arentz | :st3fan | ⏰ EST | he/him]

We do everything we need can do:

* Close all WKWebViews
* Remove persistent data stores (verified they are gone)

Opening up a new tab shows that the backend content process still had this data cached.

When the app is quit, the backend process seems to sync its data back and the persistent data stores reappear.

Comment 5

[Stefan Arentz | :st3fan | ⏰ EST | he/him]

Attachment: PR: https://github.com/mozilla/firefox-ios/pull/912

This is not awesome but it seems to be the only way. We will have actual data clearing APIs in iOS9. I am going to suggest that we use this until then.

The problem is as follows: we close all webviews and we remove all persistent stores (include the cookie database) from disk. However, the content process, to which we have no access, still has this data cached. And it simply writes it back to disk.

Exiting our app right after clearing these persistent stores also terminates or disconnects the content processes. So they cannot write the cached private data back to disk.

Comment 6

[Stefan Arentz | :st3fan | ⏰ EST | he/him]

Also disabling CPD tests because they always fail with no way to recover from the exit(0)

Comment 7

[Stefan Arentz | :st3fan | ⏰ EST | he/him]

Updated the patch with a new approach thanks to :sleroux

"As part of clearing private data we now also create a new WKProcessPool. This prevents the content processes to write back cached data to the main process. (The data that we just deleted)"

Comment 8

[Stephan Leroux [:sleroux]]

Comment on attachment 8647014 [details] [review]
PR: https://github.com/mozilla/firefox-ios/pull/912

I logged into news.ycombinator/facebook/twitter, hit clear data, and everything was gone! Can't believe this works!

Comment 9

[Aaron Train [:aaronmt]]

http://i.imgur.com/9RBRG9z.gif