1338207 - Add a test case to verify W^X page protection.

Status: NEW

(Core :: JavaScript Engine: JIT, enhancement, P5)

Description

[Nicolas B. Pierron [:nbp]]

Bug 1338179 might weakens the W^X page protection mechanism in rare cases.

We can add a non-fruzzer-friendly(*) JS Shell test case, which can be used in a expected-failing test case to double check that W-access is forbidden on the jit-code of a function given as argument.

(*) With extra bonus points if we can make it fuzzer friendly.

Comment 1

[KOLANICH]

firejail now has a pref enforcing W^X. Firefox doesn't work when it is active.

Comment 2

[Jan de Mooij [:jandem]]

(In reply to KOLANICH from comment #1)

firejail now has a pref enforcing W^X. Firefox doesn't work when it is active.

Is it possible to get a stack trace or something else to help debug this? It could be in another part of the browser.

Comment 3

[KOLANICH]

Is it possible to get a stack trace or something else to help debug this?

I have not tried, but should be possible. If you mean a crash, the app doesn't, it just hangs.

It could be in another part of the browser.

It can. I have not checked this. One of firejail maintainers guesses it may be GTK or Qt. Anyway, if we need FF being W&X-free, all the dependencies shold be fixed too.