console,util: fix missing recursion end while inspecting prototypes

This makes sure prototypes won't be inspected infinitely for some obscure object creations. The depth is now taken into account and the recursion ends when the depth limit is reached. PR-URL: #29647 Fixes: #29646 Reviewed-By: Jeremiah Senkpiel <fishrock123@rocketmail.com> Reviewed-By: Minwoo Jung <minwoo@nodesource.com>
nodejs · Sep 25, 2019 · 68630c5b65326fe27cbf107d0e91d58a46658b2d · 68630c5
1 parent 6272f82
commit 68630c5b65326fe27cbf107d0e91d58a46658b2d
Showing with 34 additions and 6 deletions.

+19 −6 lib/internal/util/inspect.js

+15 −0 test/parallel/test-util-inspect.js
diff --git a/lib/internal/util/inspect.js b/lib/internal/util/inspect.js
@@ -351,7 +351,7 @@ function getEmptyFormatArray() {
   return [];
 }
 
-function getConstructorName(obj, ctx) {
+function getConstructorName(obj, ctx, recurseTimes) {
   let firstProto;
   const tmp = obj;
   while (obj) {
@@ -372,10 +372,23 @@ function getConstructorName(obj, ctx) {
     return null;
   }
 
-  return `${internalGetConstructorName(tmp)} <${inspect(firstProto, {
-    ...ctx,
-    customInspect: false
-  })}>`;
+  const res = internalGetConstructorName(tmp);
+
+  if (recurseTimes > ctx.depth && ctx.depth !== null) {
+    return `${res} <Complex prototype>`;
+  }
+
+  const protoConstr = getConstructorName(firstProto, ctx, recurseTimes + 1);
+
+  if (protoConstr === null) {
+    return `${res} <${inspect(firstProto, {
+      ...ctx,
+      customInspect: false,
+      depth: -1
+    })}>`;
+  }
+
+  return `${res} <${protoConstr}>`;
 }
 
 function getPrefix(constructor, tag, fallback) {
@@ -570,7 +583,7 @@ function formatValue(ctx, value, recurseTimes, typedArray) {
 function formatRaw(ctx, value, recurseTimes, typedArray) {
   let keys;
 
-  const constructor = getConstructorName(value, ctx);
+  const constructor = getConstructorName(value, ctx, recurseTimes);
   let tag = value[Symbol.toStringTag];
   // Only list the tag in case it's non-enumerable / not an own property.
   // Otherwise we'd print this twice.

diff --git a/test/parallel/test-util-inspect.js b/test/parallel/test-util-inspect.js
@@ -2092,6 +2092,21 @@ assert.strictEqual(
     inspect(obj),
     "Array <[Object: null prototype] {}> { '0': 1, '1': 2, '2': 3 }"
   );
+
+  StorageObject.prototype = Object.create(null);
+  Object.setPrototypeOf(StorageObject.prototype, Object.create(null));
+  Object.setPrototypeOf(
+    Object.getPrototypeOf(StorageObject.prototype),
+    Object.create(null)
+  );
+  assert.strictEqual(
+    util.inspect(new StorageObject()),
+    'StorageObject <Object <Object <[Object: null prototype] {}>>> {}'
+  );
+  assert.strictEqual(
+    util.inspect(new StorageObject(), { depth: 1 }),
+    'StorageObject <Object <Object <Complex prototype>>> {}'
+  );
 }
 
 // Check that the fallback always works.