Harden scriptlets which need to serialize function code into string

gorhill · gorhill · commit 7823d9807007 · 2023-11-06T09:10:21.000-05:00
Related issue: uBlockOrigin/uBlock-issues#2907
diff --git a/assets/resources/scriptlets.js b/assets/resources/scriptlets.js
@@ -49,6 +49,8 @@ function safeSelf() {
     const safe = {
         'Array_from': Array.from,
         'Error': self.Error,
+        'Function_toStringFn': self.Function.prototype.toString,
+        'Function_toString': thisArg => safe.Function_toStringFn.call(thisArg),
         'Math_floor': Math.floor,
         'Math_random': Math.random,
         'Object_defineProperty': Object.defineProperty.bind(Object),
@@ -1394,7 +1396,9 @@ function addEventListenerDefuser(
                 let type, handler;
                 try {
                     type = String(args[0]);
-                    handler = String(args[1]);
+                    handler = args[1] instanceof Function
+                        ? String(safe.Function_toString(args[1]))
+                        : String(args[1]);
                 } catch(ex) {
                 }
                 const matchesType = safe.RegExp_test.call(reType, type);
@@ -2004,7 +2008,9 @@ function noRequestAnimationFrameIf(
     const reNeedle = safe.patternToRegex(needle);
     window.requestAnimationFrame = new Proxy(window.requestAnimationFrame, {
         apply: function(target, thisArg, args) {
-            const a = String(args[0]);
+            const a = args[0] instanceof Function
+                ? String(safe.Function_toString(args[0]))
+                : String(args[0]);
             let defuse = false;
             if ( log !== undefined ) {
                 log('uBO: requestAnimationFrame("%s")', a);
@@ -2072,7 +2078,9 @@ function noSetIntervalIf(
     const reNeedle = safe.patternToRegex(needle);
     self.setInterval = new Proxy(self.setInterval, {
         apply: function(target, thisArg, args) {
-            const a = String(args[0]);
+            const a = args[0] instanceof Function
+                ? String(safe.Function_toString(args[0]))
+                : String(args[0]);
             const b = args[1];
             if ( log !== undefined ) {
                 log('uBO: setInterval("%s", %s)', a, b);
@@ -2134,7 +2142,9 @@ function noSetTimeoutIf(
     const reNeedle = safe.patternToRegex(needle);
     self.setTimeout = new Proxy(self.setTimeout, {
         apply: function(target, thisArg, args) {
-            const a = String(args[0]);
+            const a = args[0] instanceof Function
+                ? String(safe.Function_toString(args[0]))
+                : String(args[0]);
             const b = args[1];
             if ( log !== undefined ) {
                 log('uBO: setTimeout("%s", %s)', a, b);
