googleapis/mcp-toolbox · error

path %q escapes configured directory %q

Error message

path %q escapes configured directory %q

What it means

Path-containment guard in ResolveWithinDir: after joining, the cleaned destination starts with '..' or is absolute relative to the configured directory, so writing/reading there would escape destination_dir (classic traversal such as '../../etc/passwd').

Source

Thrown at internal/tools/cloudstorage/cloudstoragecommon/paths.go:141

func ResolveWithinDir(dir, rel string) (string, error) {
	cleanDir, err := ValidateLocalPath(dir)
	if err != nil {
		return "", fmt.Errorf("directory %q is invalid: %w", dir, err)
	}
	if rel == "" {
		return "", fmt.Errorf("relative path is empty")
	}
	if filepath.IsAbs(rel) {
		return "", fmt.Errorf("path %q must be relative", rel)
	}

	cleanDest := filepath.Clean(filepath.Join(cleanDir, rel))
	out, err := escapes(cleanDir, cleanDest)
	if err != nil {
		return "", fmt.Errorf("path %q cannot be resolved within %q: %w", rel, cleanDir, err)
	}
	if out {
		return "", fmt.Errorf("path %q escapes configured directory %q", rel, cleanDir)
	}

	// Repeat the check against the real targets. A symlink under cleanDir can
	// point anywhere, so the name-level check above proves nothing on its own.
	resolvedDir, err := ResolveSymlinks(cleanDir)
	if err != nil {
		return "", fmt.Errorf("directory %q cannot be resolved: %w", cleanDir, err)
	}
	resolvedDest, err := ResolveSymlinks(cleanDest)
	if err != nil {
		return "", fmt.Errorf("path %q cannot be resolved: %w", rel, err)
	}
	out, err = escapes(resolvedDir, resolvedDest)
	if err != nil {
		return "", fmt.Errorf("path %q cannot be resolved within %q: %w", rel, cleanDir, err)
	}
	if out {
		return "", fmt.Errorf("path %q resolves through a symbolic link to a target outside configured directory %q", rel, cleanDir)

View on GitHub (pinned to 8cc6e09de2)

Solutions

1. Remove '..' sequences and use a plain path relative to destination_dir
2. If the file legitimately lives elsewhere, extend destination_dir rather than traversing out of it

When it happens

Trigger: Thrown at internal/tools/cloudstorage/cloudstoragecommon/paths.go:141 when the library encounters an invalid state.

Common situations: See trigger scenarios.

AI-assisted analysis of googleapis/mcp-toolbox@8cc6e09de2 (2026-09-05). Data as JSON: /api/errors/1d026774d22be191. Report an issue: GitHub.