openai/codex · error

failed to create stderr pipe for bubblewrap: {err}

Error message

failed to create stderr pipe for bubblewrap: {err}

What it means

Error "failed to create stderr pipe for bubblewrap: {err}" thrown in openai/codex.

Source

Thrown at codex-rs/linux-sandbox/src/linux_run_main.rs:1429

///   command, and reads are bounded to a fixed max size.
fn run_bwrap_in_child_capture_stderr(bwrap_args: crate::bwrap::BwrapArgs) -> String {
    const MAX_PREFLIGHT_STDERR_BYTES: u64 = 64 * 1024;
    let crate::bwrap::BwrapArgs {
        args,
        preserved_files,
        synthetic_mount_targets,
        protected_create_targets,
    } = bwrap_args;
    let setup_signal_mask = ForwardedSignalMask::block();
    let synthetic_mount_registrations = register_synthetic_mount_targets(&synthetic_mount_targets);
    let protected_create_registrations =
        register_protected_create_targets(&protected_create_targets);

    let mut pipe_fds = [0; 2];
    let pipe_res = unsafe { libc::pipe2(pipe_fds.as_mut_ptr(), libc::O_CLOEXEC) };
    if pipe_res < 0 {
        let err = std::io::Error::last_os_error();
        panic!("failed to create stderr pipe for bubblewrap: {err}");
    }
    let read_fd = pipe_fds[0];
    let write_fd = pipe_fds[1];

    let pid = unsafe { libc::fork() };
    if pid < 0 {
        let err = std::io::Error::last_os_error();
        panic!("failed to fork for bubblewrap: {err}");
    }

    if pid == 0 {
        reset_forwarded_signal_handlers_to_default();
        setup_signal_mask.restore();
        // Child: redirect stderr to the pipe, then run bubblewrap.
        unsafe {
            close_fd_or_panic(read_fd, "close read end in bubblewrap child");
            if libc::dup2(write_fd, libc::STDERR_FILENO) < 0 {
                let err = std::io::Error::last_os_error();

View on GitHub (pinned to 339751715c)

When it happens

Trigger: Thrown at codex-rs/linux-sandbox/src/linux_run_main.rs:1429 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of openai/codex@339751715c (2026-08-25). Data as JSON: /api/errors/2958f50e16d682da. Report an issue: GitHub.