1950112 - Use MITIGATION_WIN32K_DISABLE and MITIGATION_DYNAMIC_CODE_DISABLE flags for GMP process for non-widevine CDMs.

Status: RESOLVED FIXED

(Core :: Security: Process Sandboxing, enhancement, P1)

Description

[Bob Owen (:bobowen)]

Previous testing for win32k lockdown with widevine has seen intermittent crashes.
However we should be able to turn this on for non-widevine CDMs, i.e. OpenH264 and ClearKey.

Easiest way to do this is turn it on for GMP SandboxLevel::Lockdown (only widevine uses SandboxLevel::Restricted).

We could also use MITIGATION_DYNAMIC_CODE_DISABLE.

Comment 1

[Bob Owen (:bobowen)]

Attachment: Bug 1950112: Use win32k lockdown and ACG for GMP process for non-widevine CDMs. r=yjuglaret!

Comment 2

[Bob Owen (:bobowen)]

https://treeherder.mozilla.org/jobs?repo=try&revision=be6fb84582d27b8eda19eb75e4eb7250d359e3b2

Comment 3

[Jim Mathies [:jimm]]

Hey Bob, I was just testing the try build here and unfortunately ran into a crash on a webrtc demo -

https://mozilla.github.io/webrtc-landing/pc_test.html
https://crash-stats.mozilla.org/report/index/c507cdf2-14f9-4aed-a823-61a250250226

Update - fixed by setting media.gmp.use-native-event-processing=false

Comment 4

[Bob Owen (:bobowen)]

New try push with the native event processing disabled with win32k lockdown:
https://treeherder.mozilla.org/jobs?repo=try&duplicate_jobs=visible&revision=d696b8986c70b9bbf0c4558f20f88ed79643452d

Comment 5

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/f1a2f50aef13
Use win32k lockdown and ACG for GMP process for non-widevine CDMs. r=yjuglaret,win-reviewers

Comment 6

[Bob Owen (:bobowen)]

Attachment: Bug 1950112 p2: Set correct prefs for nightly builds. r=yjuglaret!

Comment 7

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/a4196fedf5da
p2: Set correct prefs for nightly builds. r=yjuglaret

Comment 8

[Serban Stanca [:SerbanS]]

https://hg.mozilla.org/mozilla-central/rev/f1a2f50aef13
https://hg.mozilla.org/mozilla-central/rev/a4196fedf5da