cached_path materialized each embedded chime to a fixed, predictable path
(/tmp/peerspeak-<name>.wav) via fs::write, which follows symlinks -> a local
attacker on a shared host could pre-plant a symlink and redirect the write. New
write_private_wav seam writes to a randomized peerspeak-<stem>-<pid>-<counter>-
<nanos>.wav name with OpenOptions::create_new (O_EXCL, refuses to write through
an existing path) and 0600 mode at creation on Unix. Per-process cache and the
None-on-error fallback (chime simply doesn't play) are unchanged.
Unit tests: exact bytes, 0600 mode, unique paths, create_new-refuses-existing.
No new deps, no wire/schema change. Codex-implemented (gpt-5.5 xhigh), reviewed.
Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
molluskandClaude Opus 4.8
10bd15aeaa