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internal/pkg/buildcfg/confgen/gen.go

@@ -30,17 +30,31 @@ type Define struct {
 
 // WriteLine writes a line of configuration.
 func (d Define) WriteLine() (s string) {
-	if len(d.Words) == 3 && len(d.Words[2]) == 1 {
-		s = "const " + d.Words[1] + " = " + d.Words[2]
-	} else {
-		s = d.Words[2]
+	s = d.Words[2]
+	if len(d.Words) > 3 {
 		for _, w := range d.Words[3:] {
 			s += " + " + w
 		}
-		s = "var " + d.Words[1] + " = RelocatePath(" + s + ")"
 	}
 
-	return s
+	// Apply runtime relocation to some variables
+	switch d.Words[1] {
+	case
+		"BINDIR",
+		"LIBEXECDIR",
+		"SYSCONFDIR",
+		"SESSIONDIR",
+		"SINGULARITY_CONFDIR",
+		"PLUGIN_ROOTDIR":
+		return "var " + d.Words[1] + " = RelocatePath(" + s + ")"
+	default:
+		var varType = "const"
+		// Some variables are defined relative to others and cannot be const
+		if strings.Contains(s, "SINGULARITY_CONFDIR") {
+			varType = "var"
+		}
+		return varType + " " + d.Words[1] + " = " + s
+	}
 }
 
 var confgenTemplate = template.Must(template.New("").Parse(`// Code generated by go generate; DO NOT EDIT.
@@ -53,6 +67,11 @@ import (
 )
 
 func RelocatePath(original string) (string) {
+	// For security, never allow relocation when built with SetUID support
+	if SINGULARITY_SUID_INSTALL == 1 {
+		return original
+	}
+
 	if ! strings.HasPrefix(original, "{{.Prefix}}") {
 		return original
 	}
@@ -70,10 +89,8 @@ func RelocatePath(original string) (string) {
 	case "starter":
 		// PREFIX/libexec/singularity/bin/starter
 		prefix = filepath.Dir(filepath.Dir(filepath.Dir(prefix)))
-	case "bash_completion":
-		return original
 	default:
-		panic("Unrecognized executable: " + executablePath)
+		return original
 	}
 
 	relativePath, err := filepath.Rel("{{.Prefix}}", original)