Skip unavailable sandbox sysctls#23015
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Bo98
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Pull request overview
This pull request makes Homebrew’s Linux sandbox setup more resilient by avoiding sysctl reads/writes for sysctl keys that are not present under /proc/sys, and by treating sysctl writes as best-effort while still surfacing any write errors.
Changes:
- Check for
/proc/sys/...presence before callingsysctl -nto avoid failures on kernels missing specific keys. - Skip sysctl writes when the corresponding
/proc/sys/...file is not writable (e.g., read-only proc mounts). - Add RSpec coverage for missing/read-only proc sysctl behavior and for preserving sysctl write error output.
Reviewed changes
Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.
| File | Description |
|---|---|
| Library/Homebrew/cmd/setup-sandbox.sh | Guard sysctl reads/writes with /proc/sys existence and writability checks; make writes best-effort while keeping stderr visible. |
| Library/Homebrew/test/cmd/setup-sandbox_spec.rb | Add test scaffolding to simulate /proc/sys and new specs for missing/read-only sysctl behavior and write-error visibility. |
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- Check `/proc/sys` entries before calling `sysctl` so kernels that omit keys do not block the Bubblewrap probe. - Skip unwritable proc sysctl files, including read-only mounts. - Keep attempted `sysctl` writes best effort and surface failed `bwrap` probe output for debugging.
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/proc/sysentries before callingsysctlso kernels that omit keys do not block the Bubblewrap probe.sysctlerrors visible while treating writes as best effort.brewcommands to reproduce the bug?brew lgtm(style, typechecking and tests) locally?OpenAI Codex 5.5 xhigh with local tweaking and review.