732496 - Assertion failure: spoff == js_ReconstructStackDepth(cx_, fp_->script(), pc_), at vm/Stack.cpp:1150 or Crash [@ CrashIfInvalidSlot]

Status: RESOLVED FIXED

(Core :: JavaScript Engine, defect)

Description

[Christian Holler (:decoder)]

Attachment: Test case for shell (see README file inside).

The attached test asserts/crashes on mozilla-central revision 343ec916dfd5 (see README for running instructions).

Crash backtrace (from opt build):

==38069== Process terminating with default action of signal 11 (SIGSEGV)
==38069==  Access not within mapped region at address 0xBAD
==38069==    at 0x8184DF3: CrashIfInvalidSlot(js::StackFrame*, JS::Value*) (Stack.cpp:1065)
==38069==    by 0x8186D2E: js::StackIter::settleOnNewState() (Stack.cpp:1153)
==38069==    by 0x80AFFBA: js::types::TypeObject::clearNewScript(JSContext*) (Stack.h:1860)
==38069==    by 0x80B3247: js::types::TypeObject::markUnknown(JSContext*) (jsinferinlines.h:1099)
==38069==    by 0x80BEFA8: js::types::TypeObject::getProperty(JSContext*, int, bool) (jsinferinlines.h:1209)
==38069==    by 0x80B457C: js::types::TypeObject::getFromPrototypes(JSContext*, int, js::types::TypeSet*, bool) (jsinfer.cpp:2774)
==38069==    by 0x80B580B: PropertyAccess(JSContext*, JSScript*, unsigned char*, js::types::TypeObject*, bool, js::types::TypeSet*, int) (jsinfer.cpp:1040)
==38069==    by 0x80BCF2F: TypeConstraintProp::newType(JSContext*, js::types::TypeSet*, js::types::Type) (jsinfer.cpp:1098)
==38069==    by 0x80763A9: js::types::TypeCompartment::resolvePending(JSContext*) (jsinferinlines.h:795)
==38069==    by 0x80B2B9F: js::types::TypeMonitorResult(JSContext*, JSScript*, unsigned char*, JS::Value const&) (jsinfer.cpp:5160)
==38069==    by 0x80C9DCD: js::Interpret(JSContext*, js::StackFrame*, js::InterpMode) (jsinferinlines.h:574)
==38069==    by 0x81C875C: js::mjit::EnterMethodJIT(JSContext*, js::StackFrame*, void*, JS::Value*, bool) (MethodJIT.cpp:1079)

Comment 1

[Luke Wagner [:luke]]

The fix is pretty simple:

diff --git a/js/src/jsinterp.cpp b/js/src/jsinterp.cpp
@@ -2694,18 +2694,19 @@ BEGIN_CASE(JSOP_CALL)
-        regs.sp = args.spAfterCall();
-        TypeScript::Monitor(cx, script, regs.pc, regs.sp[-1]);
+        Value *newsp = args.spAfterCall();
+        TypeScript::Monitor(cx, script, regs.pc, newsp[-1]);
+        regs.sp = newsp;

Brian, do you know how to generate a short test-case for this?  To error condition is to get this TypeScript::Monitor call to inspect the stack with FrameIter/StackIter (in this case a call to clearNewScript).

Comment 3

[Christian Holler (:decoder)]

(In reply to Luke Wagner [:luke] from comment #1)
> The fix is pretty simple:

Tested this fix and it worked for me (solved also other OOM situations with the same assert).

Can we get this landed or is it blocked by a better testcase?

> Brian, do you know how to generate a short test-case for this?  To error
> condition is to get this TypeScript::Monitor call to inspect the stack with
> FrameIter/StackIter (in this case a call to clearNewScript).

Would it be sufficient if this was covered by the OOM testing mechanism or do we need to cover more situations?

Comment 4

[Luke Wagner [:luke]]

Attachment: fix

Righto

Comment 5

[Brian Hackett [Laid off!]]

Comment on attachment 604562 [details] [diff] [review]
fix

Oh, this would be kind of tricky to write a small testcase for.  The new type needs to trigger type changes that invalidate a type's newScript info, which can only happen in narrow circumstances, e.g. calling foo.call in the constructor and either foo or foo.call is changed by the new type.

Comment 6

[Luke Wagner [:luke]]

https://hg.mozilla.org/integration/mozilla-inbound/rev/dd2a4596f15c

Comment 7

[Marco Bonardo [:mak]]

https://hg.mozilla.org/mozilla-central/rev/dd2a4596f15c