1870905 - Add-on metadata (addons.json) becomes empty when an update check is performed while the network is disconnected

Status: RESOLVED FIXED

(Toolkit :: Add-ons Manager, defect, P2)

Description

[Rob Wu [:robwu]]

I noticed on my phone that the metadata of installed add-ons was missing, observed through the number of reviews being zero in the add-ons manager. AddonRepository.sys.js is responsible for providing this metadata, and the data is also written to ProfD in addons.json. I read this file through a debugger, and the addons array within is empty, unexpectedly. I am sure that it was non-empty before.

Upon auditing the code responsible for it, it appears that there is a code path where addons becomes empty:

• (new in Firefox 120, bug 1850674 + bug 1859265): https://searchfox.org/mozilla-central/rev/5920b970c9996c7820c7ebf4e7b072e77017edf2/mobile/android/modules/geckoview/GeckoViewWebExtension.sys.mjs#1072-1080
• AddonRepository.backgroundUpdateCheck() looks up the add-ons to cache, and then unconditionally replaces the full addons.json database with the result at https://searchfox.org/mozilla-central/rev/5920b970c9996c7820c7ebf4e7b072e77017edf2/toolkit/mozapps/extensions/internal/AddonRepository.sys.mjs#660,690,692
• _getFullData is responsible for fetching the metadata, at https://searchfox.org/mozilla-central/rev/5920b970c9996c7820c7ebf4e7b072e77017edf2/toolkit/mozapps/extensions/internal/AddonRepository.sys.mjs#598-607
  • It swallows any error and returns an empty array if an error occurs.

What I suspect to have happened on my mobile device is:

• while the network connection is spotty or missing, Fenix wanted to perform an update check, which goes through AddonRepository.backgroundUpdateCheck.
• because the network request failed, _getFullData encountered an error and returned an empty array.
• AddonDatabase.repopulate(addons) is called with this empty array, which essentially zeroes addons.json

At minimum, a feasible fix could be to return early if addons is empty. Then the metadata isn't updated, but at least not zeroed either.

Comment 1

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

The severity field is not set for this bug.
:rpl, could you have a look please?

For more information, please visit BugBot documentation.

Comment 2

[Rob Wu [:robwu]]

Attachment: Bug 1870905 - Skip repopulate on error in AddonRepository

Comment 3

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/1d9422a3e1d8
Skip repopulate on error in AddonRepository r=willdurand

Comment 4

[Sandor Molnar[:smolnar]]

https://hg.mozilla.org/mozilla-central/rev/1d9422a3e1d8