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fix(core): Call native toString without page-replaceable lookups in FunctionToString - #25921
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…in FunctionToString (#25922) Backport of: #25921 --- `FunctionToString` could overflow the stack, it happens when a page hooks `Function.prototype.apply` or when `toString` gets a huge argument list, this can be fixed by capturing a binding to the native call once and passing no arguments. **Why does a huge argument list trigger this?** V8 only fits so many args on the stack. Our wrapper held two copies (the incoming call and our call to native `toString`), so a huge list overflows where native's single copy fits. This is mentioned on [MDN](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Function/apply#:~:text=But%20beware%3A%20by%20using%20apply()%20(or%20the%20spread%20syntax)%20with%20an%20arbitrarily%20long%20arguments%20list%2C%20you%20run%20the%20risk%20of%20exceeding%20the%20JavaScript%20engine%27s%20argument%20length%20limit.). I added tests for an apply hook that calls toString and a 100k argument call, both overflow before the fix. Related to #22515, which removed the same kind of re-entry through `Reflect.apply`. This is a guess at best at an issue that was reported, no guarantee it fixes it because it seems far fetched that this is what happened.
…unctionToString Bind the native toString once at setup instead of calling it through Function.prototype.apply, which a page can replace, and stop forwarding arguments native toString ignores. Either could overflow the stack where the native method would not.
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FunctionToStringcould overflow the stack, it happens when a page hooksFunction.prototype.applyor whentoStringgets a huge argument list, this can be fixed by capturing a binding to the native call once and passing no arguments.Why does a huge argument list trigger this? V8 only fits so many args on the stack. Our wrapper held two copies (the incoming call and our call to native
toString), so a huge list overflows where native's single copy fits. This is mentioned on MDN.I added tests for an apply hook that calls toString and a 100k argument call, both overflow before the fix.
Related to #22515, which removed the same kind of re-entry through
Reflect.apply.