Make rootfs hook chown best-effort for macOS support#7
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On macOS, non-root users cannot os.Chown to a different UID, causing InjectAuthorizedKeys to fail with EPERM. This makes VM startup impossible on macOS without root. Two-layer fix: - Host side: InjectAuthorizedKeys now uses an injected ChownFunc (defaulting to BestEffortLchown) that swallows EPERM. Uses Lchown instead of Chown to avoid following symlinks in the rootfs. - Guest side: New fixHomeOwnership step in boot.Run recursively chowns /home/sandbox and enforces SSH strict permissions (0700 for .ssh/, 0600 for files). Runs as PID 1 before cap drop, so chown always succeeds. Symlinks are skipped for safety. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
JAORMX
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Replace os.Chown with bestEffortLchown in InjectGitConfig and InjectMCPConfig hooks. On macOS, non-root users cannot chown files to a different UID, causing VM startup to fail with EPERM. bestEffortLchown uses os.Lchown (symlink-safe) and swallows permission errors. The guest init in propolis now handles authoritative ownership fixup at boot time as PID 1. Depends on stacklok/go-microvm#7. Co-Authored-By: Claude Opus 4.6 <noreply@anthropic.com>
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Summary
InjectAuthorizedKeysnow uses an injectedChownFunc(defaulting toBestEffortLchown) instead of hardos.Chown, so it no longer fails with EPERM on macOS for non-root usersBestEffortLchownusesos.Lchown(symlink-safe) and swallows permission errors — the guest init handles authoritative ownershipfixHomeOwnershipstep inboot.Runrecursively chowns/home/sandboxand enforces SSH strict permissions (0700 for.ssh/, 0600 for files) as PID 1 before cap dropTest plan
task fmt && task lint && task testpassesrecordingChownDI mock — run on any platform regardless of UIDfixhome_test.gocovers permission enforcement, nested SSH files, missing home dir, symlink path detection/home/sandboxowned by sandbox user🤖 Generated with Claude Code