* 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>
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Co-authored-by: Claude <noreply@anthropic.com>