many: update apparmor to 4.0.1

sandbox/apparmor/apparmor.go

@@ -697,7 +697,7 @@ func probeParserFeatures() ([]string, error) {
 			probe:   "prompt /foo r,",
 		},
 	}
-	_, internal, err := AppArmorParser()
+	cmd, internal, err := AppArmorParser()
 	if err != nil {
 		return []string{}, err
 	}
@@ -716,6 +716,7 @@ func probeParserFeatures() ([]string, error) {
 		features = append(features, "snapd-internal")
 	}
 	sort.Strings(features)
+	logger.Debugf("probed apparmor parser features for version %s (internal=%v): %v", appArmorParserVersion(cmd), internal, features)
 	return features, nil
 }
 
@@ -806,6 +807,20 @@ func AppArmorParser() (cmd *exec.Cmd, internal bool, err error) {
 	return nil, false, os.ErrNotExist
 }
 
+func appArmorParserVersion(cmd *exec.Cmd) string {
+	cmd.Args = append(cmd.Args, "--version")
+	output, err := cmd.CombinedOutput()
+	if err != nil {
+		return ""
+	}
+	logger.Debugf("apparmor_parser --version\n%s", output)
+	// output is like "AppArmor parser version 2.13.4\n"
+	// "Copyright ..."
+	// get the version number from the first line
+	parts := strings.Split(strings.Split(string(output), "\n")[0], " ")
+	return parts[len(parts)-1]
+}
+
 // tryAppArmorParserFeature attempts to pre-process a bit of apparmor syntax with a given parser.
 func tryAppArmorParserFeature(cmd *exec.Cmd, flags []string, rule string) error {
 	cmd.Args = append(cmd.Args, "--preprocess")