1214050 - Assertion failure: pc->sc->isGlobalContext() == pn->pn_u.name.scopeCoord.isFree(), at js/src/frontend/Parser.cpp:2211

Status: RESOLVED FIXED

(Core :: JavaScript Engine, defect)

Description

[Christian Holler (:decoder)]

The following testcase crashes on mozilla-central revision b235cfd4d8ca (build with --enable-optimize --enable-posix-nspr-emulation --enable-valgrind --enable-gczeal --disable-tests --enable-debug, run with --fuzzing-safe --no-threads):

eval(`
    with ({}) {
        with (dept) {
            var f = function() {};
        }
    }
    function f() {
`);



Backtrace:

Program received signal SIGSEGV, Segmentation fault.
0x00000000004d3104 in js::frontend::Parser<js::frontend::FullParseHandler>::checkFunctionDefinition (this=this@entry=0x7fffffffbac0, funName=..., pn_=pn_@entry=0x7fffffffabf0, kind=kind@entry=js::frontend::Statement, pbodyProcessed=pbodyProcessed@entry=0x7fffffffabd0) at js/src/frontend/Parser.cpp:2211
#0  0x00000000004d3104 in js::frontend::Parser<js::frontend::FullParseHandler>::checkFunctionDefinition (this=this@entry=0x7fffffffbac0, funName=..., pn_=pn_@entry=0x7fffffffabf0, kind=kind@entry=js::frontend::Statement, pbodyProcessed=pbodyProcessed@entry=0x7fffffffabd0) at js/src/frontend/Parser.cpp:2211
#1  0x0000000000501962 in js::frontend::Parser<js::frontend::FullParseHandler>::functionDef (this=this@entry=0x7fffffffbac0, inHandling=inHandling@entry=js::frontend::InAllowed, yieldHandling=yieldHandling@entry=js::frontend::YieldIsName, funName=funName@entry=..., kind=kind@entry=js::frontend::Statement, generatorKind=generatorKind@entry=js::NotGenerator, invoked=invoked@entry=js::frontend::Parser<js::frontend::FullParseHandler>::PredictUninvoked) at js/src/frontend/Parser.cpp:2488
#2  0x0000000000501df9 in js::frontend::Parser<js::frontend::FullParseHandler>::functionStmt (this=this@entry=0x7fffffffbac0, yieldHandling=yieldHandling@entry=js::frontend::YieldIsName, defaultHandling=defaultHandling@entry=js::frontend::NameRequired) at js/src/frontend/Parser.cpp:2969
#3  0x000000000050095d in js::frontend::Parser<js::frontend::FullParseHandler>::statement (this=this@entry=0x7fffffffbac0, yieldHandling=yieldHandling@entry=js::frontend::YieldIsName, canHaveDirectives=<optimized out>) at js/src/frontend/Parser.cpp:6865
#4  0x0000000000500df9 in js::frontend::Parser<js::frontend::FullParseHandler>::statements (this=this@entry=0x7fffffffbac0, yieldHandling=yieldHandling@entry=js::frontend::YieldIsName) at js/src/frontend/Parser.cpp:3193
#5  0x00000000004d739b in js::frontend::Parser<js::frontend::FullParseHandler>::evalBody (this=0x7fffffffbac0) at js/src/frontend/Parser.cpp:976
#6  0x0000000000a05427 in BytecodeCompiler::compileScript (this=this@entry=0x7fffffffb450, scopeChain=..., scopeChain@entry=..., evalCaller=evalCaller@entry=...) at js/src/frontend/BytecodeCompiler.cpp:604
#7  0x0000000000a058c3 in js::frontend::CompileScript (cx=cx@entry=0x7ffff6907400, alloc=<optimized out>, scopeChain=scopeChain@entry=..., enclosingStaticScope=..., enclosingStaticScope@entry=..., evalCaller=evalCaller@entry=..., options=..., srcBuf=..., source_=0x7ffff7e783e8, extraSct=extraSct@entry=0x0, sourceObjectOut=sourceObjectOut@entry=0x0) at js/src/frontend/BytecodeCompiler.cpp:849
#8  0x00000000005b875a in EvalKernel (cx=cx@entry=0x7ffff6907400, args=..., evalType=evalType@entry=DIRECT_EVAL, caller=..., scopeobj=scopeobj@entry=..., pc=<optimized out>) at js/src/builtin/Eval.cpp:342
#9  0x00000000005b8f63 in js::DirectEval (cx=cx@entry=0x7ffff6907400, args=...) at js/src/builtin/Eval.cpp:479
#10 0x00000000009d2e3d in Interpret (cx=cx@entry=0x7ffff6907400, state=...) at js/src/vm/Interpreter.cpp:3020
#11 0x00000000009dff2b in js::RunScript (cx=cx@entry=0x7ffff6907400, state=...) at js/src/vm/Interpreter.cpp:714
#12 0x00000000009e277c in js::ExecuteKernel (cx=cx@entry=0x7ffff6907400, script=..., script@entry=..., scopeChainArg=..., thisv=..., newTargetValue=..., type=<optimized out>, evalInFrame=..., evalInFrame@entry=..., result=result@entry=0x0) at js/src/vm/Interpreter.cpp:989
#13 0x00000000009e2be9 in js::Execute (cx=cx@entry=0x7ffff6907400, script=script@entry=..., scopeChainArg=..., rval=rval@entry=0x0) at js/src/vm/Interpreter.cpp:1024
#14 0x000000000083b168 in ExecuteScript (cx=cx@entry=0x7ffff6907400, scope=scope@entry=..., script=script@entry=..., rval=rval@entry=0x0) at js/src/jsapi.cpp:4505
#15 0x000000000083b343 in JS_ExecuteScript (cx=cx@entry=0x7ffff6907400, scriptArg=scriptArg@entry=...) at js/src/jsapi.cpp:4538
#16 0x0000000000428861 in RunFile (compileOnly=false, file=0x7ffff6991800, filename=0x7fffffffe04b "min.js", cx=0x7ffff6907400) at js/src/shell/js.cpp:509
#17 Process (cx=cx@entry=0x7ffff6907400, filename=0x7fffffffe04b "min.js", forceTTY=forceTTY@entry=false) at js/src/shell/js.cpp:628
#18 0x000000000048482a in ProcessArgs (op=0x7fffffffdaf0, cx=0x7ffff6907400) at js/src/shell/js.cpp:6011
#19 Shell (envp=<optimized out>, op=0x7fffffffdaf0, cx=0x7ffff6907400) at js/src/shell/js.cpp:6314
#20 main (argc=<optimized out>, argv=<optimized out>, envp=<optimized out>) at js/src/shell/js.cpp:6677
rax	0x0	0
rbx	0x7fffffffbac0	140737488337600
rcx	0x7ffff6ca53b0	140737333842864
rdx	0x0	0
rsi	0x7ffff6f7a9d0	140737336814032
rdi	0x7ffff6f791c0	140737336807872
rbp	0x7fffffffab70	140737488333680
rsp	0x7fffffffaab0	140737488333488
r8	0x7ffff7fe0780	140737354008448
r9	0x6372732f736a2f6c	7165916604736876396
r10	0x7fffffffa870	140737488332912
r11	0x7ffff6c27960	140737333328224
r12	0x7fffffffabf0	140737488333808
r13	0x7ffff6985280	140737330565760
r14	0x7fffffffabd0	140737488333776
r15	0x1	1
rip	0x4d3104 <js::frontend::Parser<js::frontend::FullParseHandler>::checkFunctionDefinition(JS::Handle<js::PropertyName*>, js::frontend::ParseNode**, js::frontend::FunctionSyntaxKind, bool*)+2148>
=> 0x4d3104 <js::frontend::Parser<js::frontend::FullParseHandler>::checkFunctionDefinition(JS::Handle<js::PropertyName*>, js::frontend::ParseNode**, js::frontend::FunctionSyntaxKind, bool*)+2148>:	movl   $0x8a3,0x0
   0x4d310f <js::frontend::Parser<js::frontend::FullParseHandler>::checkFunctionDefinition(JS::Handle<js::PropertyName*>, js::frontend::ParseNode**, js::frontend::FunctionSyntaxKind, bool*)+2159>:	callq  0x4a51d0 <abort()>

Comment 1

[Fuzzing Team]

JSBugMon: Bisection requested, result:
=== Treeherder Build Bisection Results by autoBisect ===

The "good" changeset has the timestamp "20151006132131" and the hash "d6059530b0317e6f6b141582b611469505256be4".
The "bad" changeset has the timestamp "20151006135536" and the hash "cfc1820361f599c55128b29de4332f8d06511e07".

Likely regression window: https://hg.mozilla.org/integration/mozilla-inbound/pushloghtml?fromchange=d6059530b0317e6f6b141582b611469505256be4&tochange=cfc1820361f599c55128b29de4332f8d06511e07

Comment 2

[Shu-yu Guo [:shu]]

Attachment: Don't give overwritten non-deoptimized function bindings slots in global scripts.

Comment 3

[Eric Faust [:efaust]]

Comment on attachment 8672876 [details] [diff] [review]
Don't give overwritten non-deoptimized function bindings slots in global scripts.

Review of attachment 8672876 [details] [diff] [review]:
-----------------------------------------------------------------

r=me. Another nice find for the fuzzers.

::: js/src/frontend/Parser.cpp
@@ +360,5 @@
>          for (uint32_t i = 0; i < vars_.length(); i++) {
>              if (vars_[i] == oldDecl) {
>                  // Terribly, deoptimized bindings may be updated with
>                  // optimized bindings due to hoisted function statements, so
>                  // give the new declaration a slot.

If you get fresh, you can extend this comment to mention why we exclude bindings in the global context (they can't have a slot anyway) in the comment here.

Comment 4

[Pulsebot]

https://hg.mozilla.org/integration/mozilla-inbound/rev/5d02202eb884

Comment 5

[Wes Kocher (:KWierso) (Not reading bugmail; email directly if needed)]

https://hg.mozilla.org/mozilla-central/rev/5d02202eb884