1750791 - Define a max capacity in UntrustedModulesBackupData

Status: RESOLVED FIXED

(Core :: DLL Services, enhancement)

Description

[Toshihito Kikuchi [:toshi]]

We should limit the number of loading events stored in UntrustedModulesBackupData, otherwise the process consumes high memory if a third-party application injects their modules repeatedly as we saw in Bug 1747980.

Comment 1

[Toshihito Kikuchi [:toshi]]

Attachment: Bug 1750791 - Part 1: Add LinkedList::mergeBack and LinkedList::splice. r=glandium

Comment 2

[Toshihito Kikuchi [:toshi]]

Attachment: Bug 1750791 - Part 2: Convert UntrustedModulesData::mEvents to a linked list. r=mhowell

This patch chnages the type of UntrustedModulesData::mEvents from
Vector to AutoCleanLinkedList. The purpose of this is for
UntrustedModulesBackupService to splice data easier and to discard
old loading events, which will be implemented in a subsequent patch.

Depends on D137244

Comment 3

[Toshihito Kikuchi [:toshi]]

Attachment: Bug 1750791 - Part 3: Simplify UntrustedModulesBackupService. r=mhowell

UntrustedModulesBackupService manages two UntrustedModulesBackupData
instances to hold third-party module loading events. We can simply have
two members instead of an array of two items, that makes the code more
readable.

Depends on D137245

Comment 4

[Toshihito Kikuchi [:toshi]]

Attachment: Bug 1750791 - Part 4: Reduce backup data of module loading events. r=mhowell

We use third-party loading events data for two purposes. One is to
send it as the third-party-modules ping. The other is to display it
on about:third-party. Currently we keep all loading events in memory,
but it may consume too much memory if modules injection happens too
often intentionally or unintentionally.

This patch is to discard old loading events after telemetry submission,
and also drops stack information after telemetry submission because
about:third-party does not use stack information.

Depends on D137246

Comment 5

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/c08b55356c5a
Part 1: Add LinkedList::mergeBack and LinkedList::splice. r=glandium
https://hg.mozilla.org/integration/autoland/rev/43a5f02b1160
Part 2: Convert UntrustedModulesData::mEvents to a linked list. r=mhowell
https://hg.mozilla.org/integration/autoland/rev/dd59fbaa406a
Part 3: Simplify UntrustedModulesBackupService.  r=mhowell
https://hg.mozilla.org/integration/autoland/rev/a82e42146aed
Part 4: Reduce backup data of module loading events.  r=mhowell

Comment 6

[Norisz Fay [:noriszfay]]

https://hg.mozilla.org/mozilla-central/rev/c08b55356c5a
https://hg.mozilla.org/mozilla-central/rev/43a5f02b1160
https://hg.mozilla.org/mozilla-central/rev/dd59fbaa406a
https://hg.mozilla.org/mozilla-central/rev/a82e42146aed