hermes-agent/tests/tools/test_local_cwd_permission_fallback.py
Teknium 71252f0dcb
fix(terminal): fall back when the configured cwd is unenterable, not just missing (#66306)
A root-launched CLI session can leak /root into the terminal cwd state a
non-root gateway/cron process later resolves (#65583). os.path.isdir('/root')
is True for a non-root user — stat only needs search permission on / — so
_resolve_safe_cwd returned it and subprocess.Popen(cwd='/root') died with
PermissionError: [Errno 13], failing EVERY cron job's terminal/file/search
tool on every command until restart.

_resolve_safe_cwd now requires X_OK (new _cwd_usable helper) and climbs to
the nearest enterable ancestor, logging a WARNING that names the leak class
when an existing-but-denied cwd is skipped. Missing-cwd recovery (#17558)
behavior unchanged.

E2E-verified: LocalEnvironment constructed with an unenterable cwd now runs
commands from the fallback directory instead of raising.
2026-07-17 06:54:51 -07:00

83 lines
3.1 KiB
Python

"""Regression tests for inaccessible-cwd fallback (#65583).
``/root`` leaking into a non-root gateway/cron process's terminal cwd used to
kill every command with ``PermissionError: [Errno 13] Permission denied:
'/root'`` — ``os.path.isdir('/root')`` is True for a non-root user (stat only
needs search permission on ``/``), so the old existence-only check in
``_resolve_safe_cwd`` happily returned a directory ``subprocess.Popen`` could
not enter. The fix checks X_OK and falls back to the nearest usable ancestor.
"""
import os
import sys
import tempfile
import pytest
from tools.environments.local import LocalEnvironment, _cwd_usable, _resolve_safe_cwd
@pytest.fixture
def denied_dir(tmp_path):
"""A directory that exists but cannot be entered (simulates /root)."""
d = tmp_path / "rootlike"
d.mkdir()
d.chmod(0)
yield d
d.chmod(0o755) # so pytest can clean up
needs_posix_perms = pytest.mark.skipif(
sys.platform == "win32" or os.geteuid() == 0,
reason="chmod-based access denial needs POSIX + non-root",
)
@needs_posix_perms
class TestInaccessibleCwdFallback:
def test_cwd_usable_rejects_unenterable_directory(self, denied_dir):
assert os.path.isdir(denied_dir) # the trap: stat succeeds
assert _cwd_usable(str(denied_dir)) is False
def test_resolve_safe_cwd_falls_back_from_denied_dir(self, denied_dir, tmp_path):
resolved = _resolve_safe_cwd(str(denied_dir))
assert resolved != str(denied_dir)
assert os.access(resolved, os.X_OK)
# Nearest usable ancestor is the tmp_path parent, not a random tempdir.
assert resolved == str(tmp_path)
def test_resolve_safe_cwd_climbs_past_denied_ancestor(self, denied_dir, tmp_path):
missing_child = str(denied_dir / "sub" / "dir")
resolved = _resolve_safe_cwd(missing_child)
assert os.access(resolved, os.X_OK)
assert resolved == str(tmp_path)
def test_local_environment_survives_denied_cwd(self, denied_dir):
"""The #65583 shape: env constructed with an unenterable cwd must
still execute commands instead of raising PermissionError."""
env = LocalEnvironment(cwd=str(denied_dir), timeout=30)
try:
handle = env._run_bash("echo ALIVE")
out = handle.stdout.read() if handle.stdout else b""
rc = handle.wait(timeout=15)
assert rc == 0
assert b"ALIVE" in (out if isinstance(out, bytes) else out.encode())
finally:
try:
env.cleanup()
except Exception:
pass
class TestUsableCwdBehaviorUnchanged:
def test_existing_accessible_cwd_returned_verbatim(self, tmp_path):
assert _resolve_safe_cwd(str(tmp_path)) == str(tmp_path)
def test_missing_cwd_still_climbs_to_existing_ancestor(self, tmp_path):
missing = str(tmp_path / "gone" / "deeper")
assert _resolve_safe_cwd(missing) == str(tmp_path)
def test_hopeless_path_falls_back_to_tempdir(self):
# A path whose every component is missing outside any real tree.
resolved = _resolve_safe_cwd("")
assert resolved == tempfile.gettempdir()