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Fix known_hosts race condition with concurrent clush SSH connections #2137

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Fix known_hosts race condition with concurrent clush SSH connections #2137

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24 changes: 20 additions & 4 deletions osism/commands/console.py
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Original file line number Diff line number Diff line change
@@ -1,8 +1,11 @@
# SPDX-License-Identifier: Apache-2.0

import json
import os
import shutil
import socket
import subprocess
import tempfile
from typing import Optional

from cliff.command import Command
Expand Down Expand Up @@ -201,10 +204,23 @@ def take_action(self, parsed_args):
if type_console == "ansible":
subprocess.call(f"/run-ansible-console.sh {host}", shell=True)
elif type_console == "clush":
subprocess.call(
f"/usr/local/bin/clush -l {settings.OPERATOR_USER} -g {host}",
shell=True,
)
# Create a per-invocation known_hosts file to avoid race conditions
# with fanout:64 concurrent SSH connections while still persisting
# host keys during the session.
fd, tmp_known_hosts = tempfile.mkstemp(prefix="clush_known_hosts_")
try:
os.close(fd)
if os.path.exists(KNOWN_HOSTS_PATH):
shutil.copy2(KNOWN_HOSTS_PATH, tmp_known_hosts)
subprocess.call(
f'/usr/local/bin/clush -l {settings.OPERATOR_USER}'
f' -o "-o UserKnownHostsFile={tmp_known_hosts}"'
f' -g {host}',
shell=True,
)
Comment on lines +215 to +220
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@sourcery-ai sourcery-ai bot Mar 15, 2026

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security (python.lang.security.audit.dangerous-subprocess-use-audit): Detected subprocess function 'call' without a static string. If this data can be controlled by a malicious actor, it may be an instance of command injection. Audit the use of this call to ensure it is not controllable by an external resource. You may consider using 'shlex.escape()'.

Source: opengrep

finally:
if os.path.exists(tmp_known_hosts):
os.unlink(tmp_known_hosts)
elif type_console == "ssh":
# Try to resolve as an inventory group
group_hosts = get_hosts_from_group(host)
Expand Down