Closed Bug 1328134 Opened 4 years ago Closed 3 years ago

Assertion failure: !cx->isExceptionPending(), at js/src/jscntxtinlines.h:242 with getBacktrace


(Core :: JavaScript Engine, defect)

Not set



Tracking Status
firefox51 --- wontfix
firefox52 --- fixed
firefox53 --- fixed


(Reporter: decoder, Assigned: arai)


(4 keywords, Whiteboard: [jsbugmon:update,testComment=2,origRev=57ac9f63fc69])


(1 file)

The following testcase crashes on mozilla-central revision 31ffcb82ced8 (build with --enable-posix-nspr-emulation --enable-valgrind --enable-gczeal --disable-tests --enable-debug --enable-optimize, run with --fuzzing-safe --ion-offthread-compile=off):

var lfLogBuffer = `
Function.prototype.toString = function() {
  this("", "", String(["f"]), String('a'.match()))
getBacktrace({thisprops: true});
readline = function() {}
function loadFile(lfVarx) {


Program terminated with signal SIGSEGV, Segmentation fault.
#0  js::CallJSNative (cx=cx@entry=0x7f1dff05f000, native=0x446b90 <StackDump(JSContext*, unsigned int, JS::Value*)>, args=...) at js/src/jscntxtinlines.h:242
#1  0x0000000000542c21 in js::InternalCallOrConstruct (cx=0x7f1dff05f000, args=..., construct=construct@entry=js::NO_CONSTRUCT) at js/src/vm/Interpreter.cpp:457
#2  0x0000000000543036 in InternalCall (cx=<optimized out>, args=...) at js/src/vm/Interpreter.cpp:502
#3  0x00000000005431ae in js::Call (cx=<optimized out>, fval=..., fval@entry=..., thisv=..., thisv@entry=..., args=..., rval=..., rval@entry=...) at js/src/vm/Interpreter.cpp:521
#4  0x00000000007e28ad in js::jit::InvokeFunction (cx=0x7f1dff05f000, obj=..., constructing=<optimized out>, argc=4, argv=0x7fffb9314950, rval=...) at js/src/jit/VMFunctions.cpp:114
#5  0x00007f1e005c922a in ?? ()
#6  0x0000000000000000 in ?? ()
rax	0x2052520	33891616
rbx	0x7fffb9314800	140736300402688
rcx	0x11a33f0	18494448
rdx	0x0	0
rsi	0x7f1dff67b770	139766815766384
rdi	0x7f1dff67a540	139766815761728
rbp	0x7fffb9314570	140736300402032
rsp	0x7fffb9314520	140736300401952
r8	0x7f1dff67b770	139766815766384
r9	0x7f1e0076c740	139766833530688
r10	0x0	0
r11	0x0	0
r12	0x7f1dff05f000	139766809358336
r13	0x1	1
r14	0x7fffb9314530	140736300401968
r15	0x7fffb9314888	140736300402824
rip	0x54d239 <js::CallJSNative(JSContext*, bool (*)(JSContext*, unsigned int, JS::Value*), JS::CallArgs const&)+393>
=> 0x54d239 <js::CallJSNative(JSContext*, bool (*)(JSContext*, unsigned int, JS::Value*), JS::CallArgs const&)+393>:	movl   $0x0,0x0
   0x54d244 <js::CallJSNative(JSContext*, bool (*)(JSContext*, unsigned int, JS::Value*), JS::CallArgs const&)+404>:	ud2
Flags: needinfo?(nihsanullah)
autoBisect shows this is probably related to the following changeset:

The first bad revision is:
user:        Tooru Fujisawa
date:        Sat Sep 05 21:55:06 2015 +0900
summary:     Bug 887016 - Part 9: Implement RegExp.prototype[@@match] and call it from String.prototype.match. r=till

Arai-san, is bug 887016 a likely regressor?
Flags: needinfo?(nihsanullah) → needinfo?(arai.unmht)
readline = function() {};
function f() {
    Function.prototype.toString = function () {
        this("", "", "x", 'a'.match() + "");
        thisprops: 1

Slightly more reduced testcase, reproduces on m-c rev 57ac9f63fc69.
Whiteboard: [jsbugmon:update,bisect] → [jsbugmon:update,testComment=2,origRev=57ac9f63fc69]
Unable to get the OOM_VERBOSE=1 stack because there was no series of output message similar to:

ReportOutOfMemory called
  allocation 1768
ReportOutOfMemory called
  allocation 1769
ReportOutOfMemory called
  allocation 1770
ReportOutOfMemory called
  allocation 1771
ReportOutOfMemory called
ReportOutOfMemory called
  allocation 1772
ReportOutOfMemory called

that was dumped.
StackDump should return false when JS::FormatStackDump fails, or clear exception before returning true.
Flags: needinfo?(arai.unmht)
so, this is not a regression from Bug 887016.
also, this is shell-only function that doesn't affect browser.
Added JS_ClearPendingException, since it's shell-only testing function and we already printed error message.
the testcase doesn't end when this bug is fixed, so I don't include it in this patch.
Assignee: nobody → arai.unmht
Attachment #8824010 - Flags: review?(evilpies)
Attachment #8824010 - Flags: review?(evilpies) → review+
Bug 1328134 - Clear pending exception when JS::FormatStackDump fails in StackDump. r=evilpie
Closed: 3 years ago
Resolution: --- → FIXED
Target Milestone: --- → mozilla53
Probably not worth backporting to Beta, but please request Aurora approval on this when you get a chance.
Flags: needinfo?(arai.unmht)
Comment on attachment 8824010 [details] [diff] [review]
Clear pending exception when JS::FormatStackDump fails in StackDump.

Sorry for the delay.
Same patch is applicable to mozilla-aurora.

Approval Request Comment
> [Feature/Bug causing the regression]
Bug 1043577

> [User impact if declined]
This crash happens only in debug build of JS shell.
This will affect fuzzing, and fixing this helps it to avoid hitting crash.

> [Is this code covered by automated tests?]
No, since the testcase doesn't stop if the issue is fixed.

> [Has the fix been verified in Nightly?]
At least locally, yes.

> [Needs manual test from QE? If yes, steps to reproduce]
I don't thinks this requires QE.

> [List of other uplifts needed for the feature/fix]

> [Is the change risky?]

> [Why is the change risky/not risky?]
This patch touches only shell-only testing function.
It's not exposed to browser.

> [String changes made/needed]
Flags: needinfo?(arai.unmht)
Attachment #8824010 - Flags: approval-mozilla-aurora?
Comment on attachment 8824010 [details] [diff] [review]
Clear pending exception when JS::FormatStackDump fails in StackDump.

fix assertion in debug builds, aurora52+
Attachment #8824010 - Flags: approval-mozilla-aurora? → approval-mozilla-aurora+
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