1594656 - about:support shows broken information for sandboxing

Status: RESOLVED FIXED

(Core :: Security: Process Sandboxing, defect, P5)

Description

[Landry Breuil (:gaston)]

Attachment: Capture d’écran_2019-11-07_08-47-23.png

Displays the string coming from https://searchfox.org/mozilla-central/source/toolkit/modules/Troubleshoot.jsm#172 but ... in a broken way, to say the least.

removing all those null bits and rebuilding the string says sandboxTypeError: Cc['@mozilla.org/sandbox/syscall-reporter;1'] is undefined

Just a cosmetic thing for a Tier3 platform, sure, but what could be improved there ? There's no way for a process itself to know after the fact if it's been pledged/unveiled on OpenBSD, that kind of introspection is not available on purpose, but since we call those syscalls we can store the params used/information somewhere and display it ?

Comment 1

[Landry Breuil (:gaston)]

That feels strange to me as https://searchfox.org/mozilla-central/source/toolkit/modules/Troubleshoot.jsm#792 shouldnt be reached on OpenBSD, unless AppConstants.platform lies for us...

Comment 2

[Gian-Carlo Pascutto [:gcp]]

removing all those null bits and rebuilding the string says sandboxTypeError: Cc['@mozilla.org/sandbox/syscall-reporter;1'] is undefined

Sounds like a bug with assuming unixy platforms are always using seccomp filtering, which of course only Linux is.

Comment 3

[Gian-Carlo Pascutto [:gcp]]

Oops, should have checked your link. Indeed the code is properly conditional on "linux", so it does look like AppConstants lies.

Comment 4

[Gian-Carlo Pascutto [:gcp]]

https://searchfox.org/mozilla-central/source/toolkit/modules/AppConstants.jsm#158

Anything using GTK widgets is identified as "linux". I don't think we want to change that as almost all the code assumes the platforms are "win", "macos", "android" or "linux". (And Android is Linux of course, but as it is not using GTK, it's not "linux" to us).

I think I want to add an AppConstant for either OpenBSD or for "platform with seccomp" so we can fix that part.

Comment 5

[Landry Breuil (:gaston)]

Hah, how.. infortunate. Pretty sure lots of things depend on this hidden behaviour... so yeah maybe matching on seccomp or by sandbox type would be better.

Comment 6

[Gian-Carlo Pascutto [:gcp]]

Attachment: Bug 1594656 - Don't display seccomp-bpf info on non-Linux.

Comment 7

[Gian-Carlo Pascutto [:gcp]]

Landry, can you check if this patch resolves the issues?

Comment 8

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/autoland/rev/f6bcd354c056
Don't display seccomp-bpf info on non-Linux. r=jld,froydnj

Comment 9

[Noemi Erli[:noemi_erli]]

https://hg.mozilla.org/mozilla-central/rev/f6bcd354c056

Comment 10

[Landry Breuil (:gaston)]

Attachment: Capture d’écran_2019-11-21_17-37-39.png

Finally got around to test this, and it nicely displays the sandbox level now. Thanks :gcp !