Files
windmill/backend/windmill-worker/nsjail/run.java.config.proto
Ruben Fiszel f8467f38c8 fix: prevent cross-tenant DNS poisoning via writable /etc in nsjail (#9194)
* fix: bind /etc resolver files read-only in nsjail sandboxes

* docs(nsjail): explain why per-file /etc resolver binds are load-bearing

The explicit /etc/hosts, /etc/resolv.conf and /etc/hostname binds look
like removable duplication of the read-only /etc bind above them. They
are not: on Kubernetes those files are separate kubelet bind-mounts on
top of /etc and nsjail's read-only remount is non-recursive, so without
these shadow binds they stay writable and a job can persist cross-tenant
DNS poisoning for the pod lifetime. Comment guards against a future
"dedup cleanup" silently reintroducing the vulnerability.

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

* docs(nsjail): shorten the load-bearing-bind comment to 3 lines

Co-Authored-By: Claude Opus 4.7 (1M context) <noreply@anthropic.com>

---------

Co-authored-by: Claude <noreply@anthropic.com>
2026-05-17 12:54:38 +00:00

134 lines
1.8 KiB
Protocol Buffer

name: "java run script"
mode: ONCE
hostname: "java"
log_level: ERROR
time_limit: {TIMEOUT}
disable_rl: true
cwd: "/tmp"
clone_newnet: false
clone_newuser: {CLONE_NEWUSER}
skip_setsid: true
keep_caps: false
keep_env: true
mount_proc: true
mount {
src: "/bin"
dst: "/bin"
is_bind: true
}
mount {
src: "/lib"
dst: "/lib"
is_bind: true
}
mount {
src: "/lib64"
dst: "/lib64"
is_bind: true
mandatory: false
}
mount {
src: "/usr"
dst: "/usr"
is_bind: true
}
mount {
src: "/dev/null"
dst: "/dev/null"
is_bind: true
rw: true
}
mount {
dst: "/tmp"
fstype: "tmpfs"
rw: true
options: "size=500000000"
}
mount {
src: "{JOB_DIR}/target"
dst: "/tmp/target"
is_bind: true
mandatory: false
}
mount {
src: "{JOB_DIR}/args.json"
dst: "/tmp/args.json"
is_bind: true
}
mount {
src: "{JOB_DIR}/result.json"
dst: "/tmp/result.json"
rw: true
is_bind: true
}
mount {
src: "{CACHE_DIR}"
dst: "{CACHE_DIR}"
is_bind: true
mandatory: false
}
mount {
src: "/etc"
dst: "/etc"
is_bind: true
}
# Container runtimes bind exactly these 3 files as separate submounts over
# /etc; nsjail's ro remount of /etc is non-recursive so they stay writable.
# Load-bearing -- do not remove as redundant with the /etc bind above.
mount {
src: "/etc/resolv.conf"
dst: "/etc/resolv.conf"
is_bind: true
mandatory: false
}
mount {
src: "/etc/hosts"
dst: "/etc/hosts"
is_bind: true
mandatory: false
}
mount {
src: "/etc/hostname"
dst: "/etc/hostname"
is_bind: true
mandatory: false
}
mount {
src: "/dev/random"
dst: "/dev/random"
is_bind: true
}
mount {
src: "/dev/urandom"
dst: "/dev/urandom"
is_bind: true
}
iface_no_lo: true
{SHARED_MOUNT}