1290752 - MergeSort needs to invoke callFunction

Status: RESOLVED FIXED

(Core :: JavaScript: Standard Library, defect)

Description

[André Bargull [:anba]]

Test case:
---
Function.prototype.call = function() {
    return "kaboom";
};
r = [].sort.apply(new Int8Array(0), [(a, b) => (a - b)|0]);
print("result", r);
---

Expected: Doesn't print "kaboom"
Actual: Prints "kaboom"

Comment 1

[André Bargull [:anba]]

BytecodeEmitter::emitDebugOnlyCheckSelfHosted() is not called for JSOP_FUNAPPLY/JSOP_FUNCALL, is it? Because I'd normally expect a debug warning for the (call-)method syntax in [1].

[1] http://hg.mozilla.org/mozilla-central/file/4a18b5cacb1b/js/src/builtin/Sorting.js#l240

Comment 2

[Eric Faust [:efaust]]

Attachment: Fix

Nice find, thanks!

Just remove method calls again. We re-added them optimistically when we added callContentFunction, but there's no reason to, and it avoids this kind of nonsense. This is less ergonomic, but safer.

Comment 3

[Till Schneidereit [:till]]

Comment on attachment 8777559 [details] [diff] [review]
Fix

Review of attachment 8777559 [details] [diff] [review]:
-----------------------------------------------------------------

r=me with comments addressed. Thank you for doing this.

::: js/src/frontend/Parser.cpp
@@ +8847,5 @@
>                  return handler.newSetThis(thisName, nextMember);
>              }
>  
> +            if (options().selfHostingMode && handler.isPropertyAccess(lhs)) {
> +                report(ParseError, false, null(), JSMSG_SELFHOSTED_METHOD_CALL);

I think this should be an ASSERT. There's no situation in which we would successfully complete startup after this error has been thrown, so we might just as well abort now.

::: js/src/js.msg
@@ +299,5 @@
>  MSG_DEF(JSMSG_REDECLARED_PARAM,        1, JSEXN_SYNTAXERR, "redeclaration of formal parameter {0}")
>  MSG_DEF(JSMSG_RESERVED_ID,             1, JSEXN_SYNTAXERR, "{0} is a reserved identifier")
>  MSG_DEF(JSMSG_REST_WITH_DEFAULT,       0, JSEXN_SYNTAXERR, "rest parameter may not have a default")
>  MSG_DEF(JSMSG_SELFHOSTED_TOP_LEVEL_LEXICAL, 1, JSEXN_SYNTAXERR, "self-hosted code cannot contain top-level {0} declarations")
> +MSG_DEF(JSMSG_SELFHOSTED_METHOD_CALL,  0, JSEXN_SYNTAXERR, "self-hosted code may not contain direct method calls. Use callFunction() or callContentFunction()")

... which would obviate the need for this.

Comment 4

[Pulsebot]

Pushed by [e-mail]:
https://hg.mozilla.org/integration/mozilla-inbound/rev/ec1190dcff7c
Re-disallow method calls in self-hosted code. (r=till)

Comment 5

[Eric Faust [:efaust]]

Till and I discussed the review on IRC, and agreed to go with the original patch.

Comment 6

[Carsten Book [:Tomcat]]

https://hg.mozilla.org/mozilla-central/rev/ec1190dcff7c