1 files changed, 32 insertions, 17 deletions

diff --git a/pkg/build/gvisor.go b/pkg/build/gvisor.go
index 861fced1b..89b583db6 100644
--- a/pkg/build/gvisor.go
+++ b/pkg/build/gvisor.go
@@ -27,22 +27,24 @@ func (gvisor gvisor) build(params Params) (ImageDetails, error) {
 	// Bring down bazel daemon right away. We don't need it running and consuming memory.
 	defer osutil.RunCmd(10*time.Minute, params.KernelDir, params.Compiler, "shutdown")
 
-	config := strings.Fields(string(params.Config))
+	config, err := parseGVisorConfig(params.Config)
+	if err != nil {
+		return ImageDetails{}, fmt.Errorf("cannot parse gVisor configuration: %w", err)
+	}
 	args := []string{}
 
 	target := "//runsc:runsc"
-	race := raceEnabled(config)
-	if race {
+	if config.Race {
 		args = append(args, "--@io_bazel_rules_go//go/config:race")
 		target = "//runsc:runsc-race"
 	}
-	if coverageEnabled(config) {
+	if config.Coverage {
 		coverageFiles := "//pkg/..."
 		exclusions := []string{
 			"//pkg/sentry/platform", "//pkg/ring0", // Breaks kvm.
 			"//pkg/coverage:coverage", // Too slow.
 		}
-		if race {
+		if config.Race {
 			// These targets use go:norace, which is not
 			// respected by coverage instrumentation. Race builds
 			// will be instrumented with atomic coverage (using
@@ -97,20 +99,33 @@ func (gvisor) clean(kernelDir, targetArch string) error {
 	return nil
 }
 
-func coverageEnabled(config []string) bool {
-	for _, flag := range config {
-		if flag == "-cover" {
-			return true
-		}
-	}
-	return false
+// Known gVisor configuration flags.
+const (
+	gvisorFlagCover = "-cover"
+	gvisorFlagRace  = "-race"
+)
+
+// gvisorConfig is a gVisor configuration.
+type gvisorConfig struct {
+	// Coverage represents whether code coverage is enabled.
+	Coverage bool
+
+	// Race represents whether race condition detection is enabled.
+	Race bool
 }
 
-func raceEnabled(config []string) bool {
-	for _, flag := range config {
-		if flag == "-race" {
-			return true
+// parseGVisorConfig parses a set of flags into a `gvisorConfig`.
+func parseGVisorConfig(config []byte) (gvisorConfig, error) {
+	var cfg gvisorConfig
+	for _, flag := range strings.Fields(string(config)) {
+		switch flag {
+		case gvisorFlagCover:
+			cfg.Coverage = true
+		case gvisorFlagRace:
+			cfg.Race = true
+		default:
+			return cfg, fmt.Errorf("unknown gVisor configuration flag: %q", flag)
 		}
 	}
-	return false
+	return cfg, nil
 }