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Don't attempt to structure clone unsupported types with workers disabled

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Please refer to https://developer.mozilla.org/en-US/docs/Web/API/Web_Workers_API/Structured_clone_algorithm

Based on that information, and manually testing our code, the implementation in `cloneValue` has the following shortcomings:
 - Attempting to clone `function`s is only prevented when they're part of an Object, but is currently allowed when they occur standalone.
 - Cloning of `Symbol`s is currently not prevented, which it should be since the native structured clone algorithm throws.
 - Any disallowed types should be checked first, to reduce the risk of future changes accidentally allowing something that shouldn't be supported.
This commit is contained in:
Jonas Jenwald 2021-07-03 10:11:41 +02:00
parent d80651e572
commit bdf6f733bf
1 changed files with 11 additions and 9 deletions
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20
src/display/api.js
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@ -1805,6 +1805,16 @@ class LoopbackPort {
function cloneValue(value) {
// Trying to perform a structured clone close to the spec, including
// transfers.
if (
typeof value === "function" ||
typeof value === "symbol" ||
value instanceof URL
) {
throw new Error(
`LoopbackPort.postMessage - cannot clone: ${value?.toString()}`
);
}
if (typeof value !== "object" || value === null) {
return value;
}
@ -1843,9 +1853,6 @@ class LoopbackPort {
}
return result;
}
if (value instanceof URL) {
throw new Error(`LoopbackPort.postMessage - cannot clone: ${value}`);
}
result = Array.isArray(value) ? [] : Object.create(null);
cloned.set(value, result); // Adding to cache now for cyclic references.
// Cloning all value and object properties, however ignoring properties
@ -1859,12 +1866,7 @@ class LoopbackPort {
if (typeof desc.value === "undefined") {
continue;
}
if (typeof desc.value === "function") {
if (value.hasOwnProperty?.(i)) {
throw new Error(
`LoopbackPort.postMessage - cannot clone: ${value[i]}`
);
}
if (typeof desc.value === "function" && !value.hasOwnProperty?.(i)) {
continue;
}
result[i] = cloneValue(desc.value);