Disable fault_handler logging in release builds (MLLVD-CR-24-02)

[hulthe]

Also add a reentrancy-guard to the fault handler

Mitigation for MLLVD-CR-24-01 and MLLVD-CR-24-02

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This change is 

[dlon]

Reviewed 1 of 1 files at r1, all commit messages.
Reviewable status: all files reviewed, 1 unresolved discussion (waiting on @hulthe)

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mullvad-daemon/src/exception_logging/unix.rs line 90 at r1 (raw file):

    // NOTE: `process::abort` is safer than `process::exit` because it doesn't perform any cleanup
    #[cfg(not(debug_assertions))]
    std::process::abort();

Should we instead not register a signal handler at all when debug_assertions is false? I.e. by conditionally compiling INIT_ONCE.call_once(...).

[hulthe]

Reviewable status: 0 of 1 files reviewed, 1 unresolved discussion (waiting on @dlon)

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mullvad-daemon/src/exception_logging/unix.rs line 90 at r1 (raw file):

Previously, dlon (David Lönnhager) wrote…

Should we instead not register a signal handler at all when debug_assertions is false? I.e. by conditionally compiling INIT_ONCE.call_once(...).

Removed the signal handler completely. Also reworded some comments, lmk what you think.

[dlon]

Reviewed 1 of 1 files at r2, all commit messages.
Reviewable status: complete! all files reviewed, all discussions resolved

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mullvad-daemon/src/exception_logging/unix.rs line 90 at r1 (raw file):

Previously, hulthe (Joakim Hulthe) wrote…

Removed the signal handler completely. Also reworded some comments, lmk what you think.

Nit: Do you think it would be cleaner to move the code into a module and make only that mod conditional on debug_assertions?

#[cfg(debug_assertions)]
mod inner {
    pub fn enable() {
        static INIT_ONCE: Once = Once::new();
        // ...
    }
}

#[cfg(not(debug_assertions))]
mod inner {
    pub fn enable() {
        // do nothing
    }
}

// TODO: I'm bad at naming?
pub use inner::*;

[Serock3]

Reviewed all commit messages.
Reviewable status: complete! all files reviewed, all discussions resolved

[hulthe]

Reviewable status: complete! all files reviewed, all discussions resolved

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mullvad-daemon/src/exception_logging/unix.rs line 90 at r1 (raw file):

Previously, dlon (David Lönnhager) wrote…

Nit: Do you think it would be cleaner to move the code into a module and make only that mod conditional on debug_assertions?

#[cfg(debug_assertions)]
mod inner {
    pub fn enable() {
        static INIT_ONCE: Once = Once::new();
        // ...
    }
}

#[cfg(not(debug_assertions))]
mod inner {
    pub fn enable() {
        // do nothing
    }
}

// TODO: I'm bad at naming?
pub use inner::*;

Yes i would

[dlon]

Reviewed 1 of 1 files at r3, all commit messages.
Reviewable status: complete! all files reviewed, all discussions resolved