Code running in Julia 1.8.5 sandbox fails with homedir(): no such file or directory (ENOENT)

[Andriamanitra]

Trying to run any Julia code in self-hosted Piston failed when Julia is trying to figure out the home directory (original issue: JuiceMitApfelnDrin/CodinCod#35). For whatever reason the issue does not seem to occur on emkc.org (possibly due to different libc version?).

I figured out that the issue can be worked around by setting HOME=/tmp for Julia. I'm not sure if that is a proper fix though – I feel like the sandboxing is blocking some system call that Julia's homedir() function (or more precisely uv_os_homedir from libuv) needs.

docker-compose.yml:

services:
  piston:
    image: ghcr.io/engineer-man/piston
    container_name: piston
    restart: always
    privileged: true
    ports:
      - 2000:2000
    volumes:
      - ./data/piston/packages:/piston/packages
    tmpfs:
      - /tmp:exec

Commands to reproduce:

# start piston
docker compose up -d

# install julia 1.8.5
curl --json '{"language":"julia","version":"1.8.5"}' http://localhost:2000/api/v2/packages

# try to execute println(123)
curl --json '{"language":"julia","version":"1.8.5","files":[{"content":"println(123)"}]}' http://localhost:2000/api/v2/execute

Execution result:

{
  "run": {
    "signal": "SIGKILL",
    "stdout": "",
    "stderr": "fatal: error thrown and no exception handler available.\nInitError(mod=:Base, error=Base.IOError(msg=\"homedir(): no such file or directory (ENOENT)\", code=-2))\nuv_error at ./libuv.jl:97 [inlined]\nhomedir at ./path.jl:75\nappend_default_depot_path! at ./initdefs.jl:90\ninit_depot_path at ./initdefs.jl:112\n__init__ at ./Base.jl:488\njfptr___init___32760.clone_1 at /piston/packages/julia/1.8.5/lib/julia/sys.so (unknown line)\n_jl_invoke at /piston/packages/julia/1.8.5/build/src/gf.c:2377 [inlined]\nijl_apply_generic at /piston/packages/julia/1.8.5/build/src/gf.c:2559\njl_apply at /piston/packages/julia/1.8.5/build/src/julia.h:1843 [inlined]\njl_module_run_initializer at /piston/packages/julia/1.8.5/build/src/toplevel.c:75\n_finish_julia_init at /piston/packages/julia/1.8.5/build/src/init.c:765\njulia_init at /piston/packages/julia/1.8.5/build/src/init.c:698\njl_repl_entrypoint at /piston/packages/julia/1.8.5/build/src/jlapi.c:713\nmain at julia (unknown line)\nSandbox keeper received fatal signal 6\n",
    "code": null,
    "output": "fatal: error thrown and no exception handler available.\nInitError(mod=:Base, error=Base.IOError(msg=\"homedir(): no such file or directory (ENOENT)\", code=-2))\nuv_error at ./libuv.jl:97 [inlined]\nhomedir at ./path.jl:75\nappend_default_depot_path! at ./initdefs.jl:90\ninit_depot_path at ./initdefs.jl:112\n__init__ at ./Base.jl:488\njfptr___init___32760.clone_1 at /piston/packages/julia/1.8.5/lib/julia/sys.so (unknown line)\n_jl_invoke at /piston/packages/julia/1.8.5/build/src/gf.c:2377 [inlined]\nijl_apply_generic at /piston/packages/julia/1.8.5/build/src/gf.c:2559\njl_apply at /piston/packages/julia/1.8.5/build/src/julia.h:1843 [inlined]\njl_module_run_initializer at /piston/packages/julia/1.8.5/build/src/toplevel.c:75\n_finish_julia_init at /piston/packages/julia/1.8.5/build/src/init.c:765\njulia_init at /piston/packages/julia/1.8.5/build/src/init.c:698\njl_repl_entrypoint at /piston/packages/julia/1.8.5/build/src/jlapi.c:713\nmain at julia (unknown line)\nSandbox keeper received fatal signal 6\n",
    "memory": 116596000,
    "message": "stderr length exceeded",
    "status": "EL",
    "cpu_time": 153,
    "wall_time": 167
  },
  "language": "julia",
  "version": "1.8.5"
}

Version info:

* OpenSUSE Tumbleweed
* Linux 6.12.9-1-default #1 SMP PREEMPT_DYNAMIC Fri Jan 10 08:30:10 UTC 2025 (0ae2136) x86_64
* GLIBC 2.40
* Docker version 27.4.1-ce, build c710b88579fc