CVE-2016-3377

@@ -287,6 +287,11 @@ class BVUnitT
         T mask = ((T)AllOnesMask) >> (BitsPerWord - length) << index;
         return (this->word & mask) == mask;
     }
+    BOOLEAN TestAnyInRange(const BVIndex index, uint length) const
+    {
+        T mask = ((T)AllOnesMask) >> (BitsPerWord - length) << index;
+        return (this->word & mask) != 0;
+    }
     void SetRange(const BVIndex index, uint length)
     {
         T mask = ((T)AllOnesMask) >> (BitsPerWord - length) << index;

@@ -485,7 +485,7 @@ void Heap::FreeLargeObjects()
 #endif
         this->codePageAllocators->Release(allocation.address, allocation.GetPageCount(), allocation.largeObjectAllocation.segment);
 
-            largeObjectIter.RemoveCurrent(this->auxiliaryAllocator);
+        largeObjectIter.RemoveCurrent(this->auxiliaryAllocator);
     }
     NEXT_DLISTBASE_ENTRY_EDITING;
 }
@@ -519,7 +519,13 @@ bool Heap::AllocInPage(Page* page, size_t bytes, ushort pdataCount, ushort xdata
 
     uint length = GetChunkSizeForBytes(bytes);
     BVIndex index = GetFreeIndexForPage(page, bytes);
-    Assert(index != BVInvalidIndex);
+    
+    if (index == BVInvalidIndex)
+    {
+        CustomHeap_BadPageState_fatal_error((ULONG_PTR)this);
+        return false;
+    }
+
     char* address = page->address + Page::Alignment * index;
 
 #if PDATA_ENABLED
@@ -562,6 +568,13 @@ bool Heap::AllocInPage(Page* page, size_t bytes, ushort pdataCount, ushort xdata
     this->freeObjectSize -= bytes;
 #endif
 
+    //Section of the Page should already be freed.
+    if (!page->freeBitVector.TestRange(index, length))
+    {
+        CustomHeap_BadPageState_fatal_error((ULONG_PTR)this);
+        return false;
+    }
+
     page->freeBitVector.ClearRange(index, length);
     VerboseHeapTrace(_u("ChunkSize: %d, Index: %d, Free bit vector in page: "), length, index);
 
@@ -729,18 +742,19 @@ bool Heap::FreeAllocation(Allocation* object)
     unsigned int length = GetChunkSizeForBytes(object->size);
     BVIndex index = GetIndexInPage(page, object->address);
 
-#if DBG
-    // Make sure that it's not already been freed
-    for (BVIndex i = index; i < length; i++)
+    uint freeBitsCount = page->freeBitVector.Count();
+
+    // Make sure that the section under interest or the whole page has not already been freed
+    if (page->IsEmpty() || page->freeBitVector.TestAnyInRange(index, length))
     {
-        Assert(!page->freeBitVector.Test(i));
+        CustomHeap_BadPageState_fatal_error((ULONG_PTR)this);
+        return false;
     }
-#endif
 
     if (page->inFullList)
     {
         VerboseHeapTrace(_u("Recycling page 0x%p because address 0x%p of size %d was freed\n"), page->address, object->address, object->size);
-
+       
         // If the object being freed is equal to the page size, we're
         // going to remove it anyway so don't add it to a bucket
         if (object->size != pageSize)
@@ -777,14 +791,43 @@ bool Heap::FreeAllocation(Allocation* object)
     // If the page is about to become empty then we should not need
     // to set it to executable and we don't expect to restore the
     // previous protection settings.
-    if (page->freeBitVector.Count() == BVUnit::BitsPerWord - length)
+    if (freeBitsCount == BVUnit::BitsPerWord - length)
     {
         EnsureAllocationWriteable(object);
+        FreeAllocationHelper(object, index, length);
+        Assert(page->IsEmpty());
+
+        this->buckets[page->currentBucket].RemoveElement(this->auxiliaryAllocator, page);
+        return false;
     }
     else
     {
         EnsureAllocationExecuteWriteable(object);
+
+        FreeAllocationHelper(object, index, length);
+
+        // after freeing part of the page, the page should be in PAGE_EXECUTE_READWRITE protection, and turning to PAGE_EXECUTE (always with TARGETS_NO_UPDATE state)
+
+        DWORD protectFlags = 0;
+
+        if (AutoSystemInfo::Data.IsCFGEnabled())
+        {
+            protectFlags = PAGE_EXECUTE_RO_TARGETS_NO_UPDATE;
+        }
+        else
+        {
+            protectFlags = PAGE_EXECUTE;
+        }
+
+        this->codePageAllocators->ProtectPages(page->address, 1, segment, protectFlags, PAGE_EXECUTE_READWRITE);
+        
+        return true;
     }
+}
+
+void Heap::FreeAllocationHelper(Allocation* object, BVIndex index, uint length)
+{
+    Page* page = object->page;
 
     // Fill the old buffer with debug breaks
     CustomHeap::FillDebugBreak((BYTE *)object->address, object->size);
@@ -796,6 +839,7 @@ bool Heap::FreeAllocation(Allocation* object)
     VerboseHeapTrace(_u("\n"));
 
     page->freeBitVector.SetRange(index, length);
+
     VerboseHeapTrace(_u("Free bit vector in page: "), length, index);
 #if VERBOSE_HEAP
     page->freeBitVector.DumpWord();
@@ -808,29 +852,6 @@ bool Heap::FreeAllocation(Allocation* object)
 #endif
 
     this->auxiliaryAllocator->Free(object, sizeof(Allocation));
-
-    if (page->IsEmpty())
-    {
-        this->buckets[page->currentBucket].RemoveElement(this->auxiliaryAllocator, page);
-        return false;
-    }
-    else // after freeing part of the page, the page should be in PAGE_EXECUTE_READWRITE protection, and turning to PAGE_EXECUTE (always with TARGETS_NO_UPDATE state)
-    {
-        DWORD protectFlags = 0;
-
-        if (AutoSystemInfo::Data.IsCFGEnabled())
-        {
-            protectFlags = PAGE_EXECUTE_RO_TARGETS_NO_UPDATE;
-        }
-        else
-        {
-            protectFlags = PAGE_EXECUTE;
-        }
-
-        this->codePageAllocators->ProtectPages(page->address, 1, segment, protectFlags, PAGE_EXECUTE_READWRITE);
-        
-        return true;
-    }
 }
 
 void Heap::FreeDecommittedBuckets()

@@ -504,6 +504,7 @@ class Heap
     void FreeBucket(DListBase<Page>* bucket, bool freeOnlyEmptyPages);
     void FreePage(Page* page);
     bool FreeAllocation(Allocation* allocation);
+    void FreeAllocationHelper(Allocation * allocation, BVIndex index, uint length);
 
 #if PDATA_ENABLED
     void FreeXdata(XDataAllocation* xdata, void* segment);

@@ -518,8 +518,8 @@ class PageAllocatorBase
 #if DBG_DUMP
     virtual void DumpStats() const;
 #endif
-    virtual PageSegmentBase<TVirtualAlloc> * AddPageSegment(DListBase<PageSegmentBase<TVirtualAlloc>>& segmentList);
-    static PageSegmentBase<TVirtualAlloc> * AllocPageSegment(DListBase<PageSegmentBase<TVirtualAlloc>>& segmentList, 
+    PageSegmentBase<TVirtualAlloc> * AddPageSegment(DListBase<PageSegmentBase<TVirtualAlloc>>& segmentList);
+    static PageSegmentBase<TVirtualAlloc> * AllocPageSegment(DListBase<PageSegmentBase<TVirtualAlloc>>& segmentList,
     PageAllocatorBase<TVirtualAlloc> * pageAllocator, bool committed, bool allocated);
 
     // Zero Pages

@@ -816,6 +816,7 @@ Symbol* Parser::AddDeclForPid(ParseNodePtr pnode, IdentPtr pid, SymbolType symbo
         && blockInfo->pnodeBlock->sxBlock.blockType == PnodeBlockType::Function
         && blockInfo->pBlockInfoOuter != nullptr
         && blockInfo->pBlockInfoOuter->pnodeBlock->sxBlock.blockType == PnodeBlockType::Parameter
+        && blockInfo->pnodeBlock->sxBlock.scope->GetScopeType() != ScopeType_FuncExpr
         && blockInfo->pBlockInfoOuter->pnodeBlock->sxBlock.scope->GetCanMergeWithBodyScope())
     {
         blockInfo = blockInfo->pBlockInfoOuter;
@@ -5029,6 +5030,13 @@ bool Parser::ParseFncDeclHelper(ParseNodePtr pnodeFnc, ParseNodePtr pnodeFncPare
                         }
                         return false;
                     });
+
+                    if (wellKnownPropertyPids.arguments->GetTopRef() && wellKnownPropertyPids.arguments->GetTopRef()->GetScopeId() > pnodeFnc->sxFnc.pnodeScopes->sxBlock.blockId)
+                    {
+                        Assert(pnodeFnc->sxFnc.UsesArguments());
+                        // Arguments symbol is captured in the param scope
+                        paramScope->SetCannotMergeWithBodyScope();
+                    }
                 }
             }
         }
@@ -5895,13 +5903,6 @@ bool Parser::ParseFncNames(ParseNodePtr pnodeFnc, ParseNodePtr pnodeFncParent, u
             pnodeFnc->sxFnc.pid = m_phtbl->PidHashNameLen(
                 m_pscan->PchBase() + ichMinNames, ichLimNames - ichMinNames);
         }
-
-        if(pnodeFnc->sxFnc.pid == wellKnownPropertyPids.arguments && fDeclaration && pnodeFncParent)
-        {
-            // This function declaration (or function expression in compat modes) overrides the built-in arguments object of the
-            // parent function
-            pnodeFncParent->grfpn |= PNodeFlags::fpnArguments_overriddenByDecl;
-        }
     }
 
     return true;
@@ -6670,10 +6671,11 @@ void Parser::AddArgumentsNodeToVars(ParseNodePtr pnodeFnc)
     }
     else
     {
+        ParseNodePtr argNode = nullptr;
         if(m_ppnodeVar == &pnodeFnc->sxFnc.pnodeVars)
         {
             // There were no var declarations in the function
-            CreateVarDeclNode(wellKnownPropertyPids.arguments, STVariable, true, pnodeFnc)->grfpn |= PNodeFlags::fpnArguments;
+            argNode = CreateVarDeclNode(wellKnownPropertyPids.arguments, STVariable, true, pnodeFnc);
         }
         else
         {
@@ -6684,10 +6686,18 @@ void Parser::AddArgumentsNodeToVars(ParseNodePtr pnodeFnc)
             // object until it is replaced with something else.
             ParseNodePtr *const ppnodeVarSave = m_ppnodeVar;
             m_ppnodeVar = &pnodeFnc->sxFnc.pnodeVars;
-            CreateVarDeclNode(wellKnownPropertyPids.arguments, STVariable, true, pnodeFnc)->grfpn |= PNodeFlags::fpnArguments;
+            argNode = CreateVarDeclNode(wellKnownPropertyPids.arguments, STVariable, true, pnodeFnc);
             m_ppnodeVar = ppnodeVarSave;
         }
 
+        Assert(argNode);
+        argNode->grfpn |= PNodeFlags::fpnArguments;
+
+        // When a function definition with the name arguments occurs in the body the declaration of the arguments symbol will
+        // be set to that function declaration. We should change it to arguments declaration from the param scope as it may be
+        // used in the param scope and we have to load the arguments.
+        argNode->sxVar.sym->SetDecl(argNode);
+
         pnodeFnc->sxFnc.SetHasReferenceableBuiltInArguments(true);
     }
 }

@@ -3693,7 +3693,9 @@ void EnsureFncDeclScopeSlot(ParseNode *pnodeFnc, FuncInfo *funcInfo)
     {
         Assert(pnodeFnc->sxFnc.pnodeName->nop == knopVarDecl);
         Symbol *sym = pnodeFnc->sxFnc.pnodeName->sxVar.sym;
-        if (sym)
+        // If this function is shadowing the arguments symbol in body then skip it.
+        // We will allocate scope slot for the arguments symbol during EmitLocalPropInit.
+        if (sym && !sym->GetIsArguments())
         {
             sym->EnsureScopeSlot(funcInfo);
         }

@@ -9019,7 +9019,7 @@ namespace Js
 
                     if (newArr)
                     {
-                        newArr->DirectSetItemAt(k, mappedValue);
+                        newArr->SetItem(k, mappedValue, PropertyOperation_None);
                     }
                     else
                     {

@@ -380,7 +380,241 @@ var tests = [
     body: function () {

         assert.doesNotThrow(function () { eval("[ (a = function () { }) => {} ];"); }, "Lambda defined, inside an array literal, has a default as a function should not assert");

     }

-  }

+  },

+  {

+    name: "Shadowing arguments symbol",

+    body: function () {

+        function f1(a, b = arguments[0]) {

+            assert.areEqual(1, arguments[0], "Initial value of arguments symbol in the body should be same as the arguments from the param scope");

+            var arguments = [10, 20];

+            assert.areEqual(1, b, "Arguments value is the initial value in the param scope too");

+            assert.areEqual(10, arguments[0], "Arguments value is updated in the body");

+        }

+        f1(1);

+

+        function f2(a = 1, arguments) {

+            assert.areEqual(2, arguments, "Initial value of arguments symbol in the body should be same as the arguments from the param scope");

+            var arguments = [10, 20];

+            assert.areEqual(10, arguments[0], "Arguments value is updated in the body");

+        }

+        f2(undefined, 2);

+

+        function f3(a, b = arguments[0]) {

+            assert.areEqual(10, arguments(), "Arguments symbol is overwritten by the the function definition");

+            function arguments() {

+                return 10;

+            }

+            assert.areEqual(1, b, "Arguments value is the initial value in the param scope too");

+        }

+        f3(1);

+

+        function f4(a = 1, arguments, c = arguments) {

+            assert.areEqual(10, arguments(), "In the body function definition shadows the formal");

+            assert.areEqual(2, c, "Value of the formal is assigned properly");

+            function arguments() {

+                return 10;

+            }

+        }

+        f4(undefined, 2);

+

+        function f5(a, b = arguments) {

+            function arguments(c) {

+                return arguments;

+            }

+            assert.areEqual(30, arguments(10, 20, 30)[2], "Inside the arguments function the arguments symbol should points to the passed in values");

+            assert.areEqual(4, b[3], "In the param scope arguments symbol referes to the passed in values");

+        }

+        f5(1, undefined, 3, 4, 5);

+

+        function f6(a, b = arguments) {

+            function arguments(c) {

+                if (!arguments.length) {

+                    return arguments.callee(10, 20, 30);

+                }

+                return arguments;

+            }

+            assert.areEqual(20, arguments()[1], "In the function body arguments refers to the inner function");

+            assert.areEqual(3, b[2], "In the param scope arguments symbol referes to the passed in values");

+        }

+        f6(1, undefined, 3, 4);

+

+        function f7(a, b = function arguments(c) {

+            if (!c) {

+                return arguments.callee(10, 20);

+            }

+            return c + arguments[1];

+        }) {

+            assert.areEqual(30, b(), "Function defined in the param scope can be called recursively");

+            assert.areEqual(1, arguments[0], "Arguments symbol is unaffected by the function expression");

+        }

+        f7(1);

+

+        function f8(a, b = arguments) {

+            var c = function arguments(c) {

+                if (!arguments.length) {

+                    return arguments.callee(10, 20, 30);

+                }

+                return arguments;

+            }

+            assert.areEqual(30, c()[2], "In the function body the arguments function expression with name is not visible");

+            assert.areEqual(1, b[0], "In the param scope arguments symbol referes to the passed in values");

+        }

+        f8(1);

+

+        assert.throws(function () { eval("function f(a, b = arguments) { class arguments { } }"); }, SyntaxError, "Class cannot be named arguments", "Invalid usage of 'arguments' in strict mode");

+        assert.throws(function () { eval("function f(a, arguments) { class arguments { } }"); }, SyntaxError, "Class cannot be named arguments even when one of the formal is named arguments", "Let/Const redeclaration");

+

+        function f9( a = 0, b = {

+            arguments() {

+                return 10;

+            }

+        }, c = arguments) {

+            with (b) {

+                assert.areEqual(10, arguments(), "Inside with the right the arguments function inside the object is used in the body also");

+            }

+            assert.areEqual(1, arguments[0], "Arguments symbol should be unaffected after with construct");

+            assert.areEqual(1, c[0], "Arguments symbol from param scope should be unaffected after with construct");

+        }

+        f9(1);

+

+        function f10(a = 1, b = () => {

+            assert.areEqual(undefined, arguments, "Due to the decalration in the body arguments symbol is shadowed inside the lambda");

+            var arguments = 100;

+            assert.areEqual(100, arguments, "After the assignment value of arguments is updated inside the lambda");

+        }, c = arguments) {

+            assert.areEqual(10, arguments[0], "In the body the value of arguments is retained");

+            assert.areEqual(10, c[0], "Arguments symbol is not affected in the param scope");

+            b();

+        }

+        f10(10);

+

+        function f11(a = 1, b = () => {

+            assert.areEqual(100, arguments(), "Inside the lambda the function definition shadows the parent's arguments symbol");

+            function arguments() {

+                return 100;

+            }

+        }, c = arguments) {

+            assert.areEqual(10, arguments[0], "In the body the value of arguments is retained");

+            b();

+            assert.areEqual(10, c[0], "Arguments symbol is not affected in the param scope");

+        }

+        f11(10);

+

+        function f12({a = 1, arguments}) {

+            assert.areEqual(2, arguments, "Initial value of arguments symbol in the body should be same as the arguments from the param scope's destructured pattern");

+            var arguments = [10, 20];

+            assert.areEqual(10, arguments[0], "Arguments value is updated in the body");

+        }

+        f12({arguments : 2});

+

+        function f13(a = 1, {arguments, c = arguments}) {

+            assert.areEqual(10, arguments(), "In the body function definition shadows the destructured formal");

+            assert.areEqual(2, c, "Value of the formal is assigned properly");

+            function arguments() {

+                return 10;

+            }

+        }

+        f13(undefined, { arguments: 2 });

+

+        function f14(a, b = arguments[0]) {

+            assert.areEqual(1, arguments[0], "Function in block causes a var declaration to be hoisted and the initial value should be same as the arguments symbol");

+            {

+                {

+                    function arguments() {

+                        return 10;

+                    }

+                }

+            }

+            assert.areEqual(1, b, "Arguments value is the initial value in the param scope too");

+            assert.areEqual(10, arguments(), "Hoisted var binding is updated after the block is exected");

+        }

+        f14(1);

+

+        function f15() {

+            function f16() {

+                eval("");

+                this.arguments = 1;

+            }

+

+            var obj = new f16();

+            

+            function arguments() {

+                return 10;

+            }

+            assert.areEqual(1, obj.arguments, "Child function having eval should work fine with a duplicate arguments definition in the parent body");

+        };

+        f15();

+    }

+  },

+  {

+    name: "Shadowing arguments symbol - Eval",

+    body: function () {

+        function f1(a, b = arguments[0]) {

+            assert.areEqual(1, arguments[0], "Initial value of arguments symbol in the body should be same as the arguments from the param scope");

+            var arguments = [10, 20];

+            assert.areEqual(1, b, "Arguments value is the initial value in the param scope too");

+            assert.areEqual(10, eval("arguments[0]"), "Arguments value is updated in the body");

+        }

+        f1(1);

+

+        function f2(a = 1, arguments) {

+            assert.areEqual(2, eval("arguments"), "Initial value of arguments symbol in the body should be same as the arguments from the param scope");

+            var arguments = [10, 20];

+            assert.areEqual(10, arguments[0], "Arguments value is updated in the body");

+        }

+        f2(undefined, 2);

+

+        function f3(a, b = arguments[0]) {

+            assert.areEqual(10, eval("arguments()"), "Arguments symbol is overwritten by the the function definition");

+            function arguments() {

+                return 10;

+            }

+            assert.areEqual(1, b, "Arguments value is the initial value in the param scope too");

+        }

+        f3(1);

+

+        function f4(a = 1, arguments, c = arguments) {

+            assert.areEqual(10, arguments(), "In the body function definition shadows the formal");

+            assert.areEqual(2, eval("c"), "Value of the formal is assigned properly");

+            function arguments() {

+                return 10;

+            }

+        }

+        f4(undefined, 2);

+

+        function f5(a, b, c = arguments) {

+            function arguments(c) {

+                return eval("arguments");

+            }

+            assert.areEqual(30, arguments(10, 20, 30)[2], "In the function body arguments refers to the inner function");

+            assert.areEqual(2, c[1], "In the param scope arguments symbol referes to the passed in values");

+        }

+        f5(1, 2, undefined, 4);

+

+        function f6(a, b = function arguments(c) {

+            if (!c) {

+                return arguments.callee(10, 20);

+            }

+            return c + arguments[1];

+        }) {

+            assert.areEqual(30, eval("b()"), "Function defined in the param scope can be called recursively");

+            assert.areEqual(1, arguments[0], "Arguments symbol is unaffected by the function expression");

+        }

+        f6(1);

+

+        function f7(a, b = arguments) {

+            var c = function arguments(c) {

+                if (!arguments.length) {

+                    return arguments.callee(10, 20, 30);

+                }

+                return arguments;

+            }

+            assert.areEqual(10, eval("c()[0]"), "In the function body the arguments function expression with name is not visible");

+            assert.areEqual(4, b[3], "In the param scope arguments symbol referes to the passed in values");

+        }

+        f7(1, undefined, 3, 4);

+    }

+ }

 ];

 

 testRunner.runTests(tests, { verbose: WScript.Arguments[0] != "summary" });

@@ -734,9 +734,18 @@ var tests = [
         assert.throws(function () { eval("function f(a = 10, b = (c = arguments) => a) { }"); }, SyntaxError, "Use of arguments symbol is not allowed in non-simple parameter list when captured in a lambda in split scope", "Use of 'arguments' in non-simple parameter list is not supported when one of the formals is captured");
         assert.throws(function () { eval("function f(a, b = () => a, c = () => { return arguments; }) { }"); }, SyntaxError, "Use of arguments symbol is not allowed in non-simple parameter list in split scope when captured by a lambda method", "Use of 'arguments' in non-simple parameter list is not supported when one of the formals is captured");
         assert.throws(function () { eval("function f(a = 10, b = () => a, c = () => () => arguments) { }"); }, SyntaxError, "Use of arguments symbol is not allowed in non-simple parameter list in split scope when captured by nested lambda", "Use of 'arguments' in non-simple parameter list is not supported when one of the formals is captured");
-        assert.throws(function () { eval("function f3(a, arguments = function () { return a; } ) { }"); }, SyntaxError, "Use of arguments as a parameter name is not allowed in non-simple parameter list in split scope when captured by nested lambda", "Use of 'arguments' in non-simple parameter list is not supported when one of the formals is captured");
-        assert.throws(function () { eval("function f3({a, arguments = function () { return a; }}) { }"); }, SyntaxError, "Use of arguments as a parameter name is not allowed in destructuring parameter list in split scope when captured by nested lambda", "Use of 'arguments' in non-simple parameter list is not supported when one of the formals is captured");
-        assert.throws(function () { eval("function f3({a = arguments}, b = function () { return a; } ) { }"); }, SyntaxError, "Use of arguments is not allowed in destructuring parameter list in split scope when captured by nested lambda", "Use of 'arguments' in non-simple parameter list is not supported when one of the formals is captured");
+        assert.throws(function () { eval("function f(a, arguments = function () { return a; } ) { }"); }, SyntaxError, "Use of arguments as a parameter name is not allowed in non-simple parameter list in split scope when captured by nested lambda", "Use of 'arguments' in non-simple parameter list is not supported when one of the formals is captured");
+        assert.throws(function () { eval("function f({a, arguments = function () { return a; }}) { }"); }, SyntaxError, "Use of arguments as a parameter name is not allowed in destructuring parameter list in split scope when captured by nested lambda", "Use of 'arguments' in non-simple parameter list is not supported when one of the formals is captured");
+        assert.throws(function () { eval("function f({a = arguments}, b = function () { return a; } ) { }"); }, SyntaxError, "Use of arguments is not allowed in destructuring parameter list in split scope when captured by nested lambda", "Use of 'arguments' in non-simple parameter list is not supported when one of the formals is captured");
+        assert.throws(function () { eval("function f(a = () => arguments) { }"); }, SyntaxError, "Arguments cannot be captured in the param scope", "Use of 'arguments' in non-simple parameter list is not supported when one of the formals is captured");
+        assert.throws(function () { eval("function f(a = () => arguments[0]) { }"); }, SyntaxError, "Arguments cannot be captured in the param scope", "Use of 'arguments' in non-simple parameter list is not supported when one of the formals is captured");
+        assert.throws(function () { eval("function f(a = 1, b = () => arguments[0]) { }"); }, SyntaxError, "Arguments cannot be captured in the param scope at any position", "Use of 'arguments' in non-simple parameter list is not supported when one of the formals is captured");
+        assert.throws(function () { eval("function f(a = () => arguments[0] + b, b = 10) { }"); }, SyntaxError, "Arguments cannot be captured in the param scope at any position", "Use of 'arguments' in non-simple parameter list is not supported when one of the formals is captured");
+        assert.throws(function () { eval("function f(a = () => arguments) { var arguments }"); }, SyntaxError, "Arguments cannot be captured in the param scope even when duplicate definition occurs in the body", "Use of 'arguments' in non-simple parameter list is not supported when one of the formals is captured");
+        assert.throws(function () { eval("function f(a = () => arguments) { function arguments() { } }"); }, SyntaxError, "Arguments cannot be captured in the param scope even when duplicate definition occurs in the body", "Use of 'arguments' in non-simple parameter list is not supported when one of the formals is captured");
+        assert.throws(function () { eval("function f(arguments, b = () => arguments) { }"); }, SyntaxError, "Arguments cannot be captured in the param scope even if it is a formal shadowing the actual arguments", "Use of 'arguments' in non-simple parameter list is not supported when one of the formals is captured");
+        assert.throws(function () { eval("function f({a, arguments}, b = () => a) { }"); }, SyntaxError, "Arguments cannot be used as a formal name when one of the formal is captured", "Use of 'arguments' in non-simple parameter list is not supported when one of the formals is captured");
+        assert.throws(function () { eval("function f(a, {arguments, b = () => arguments}) { }"); }, SyntaxError, "Arguments cannot be used as a formal name when one of the formal is captured", "Use of 'arguments' in non-simple parameter list is not supported when one of the formals is captured");
         
         function f1(a, b = () => a) {
             eval("");
@@ -913,6 +922,83 @@ var tests = [
             }
         }
         assert.areEqual([2, 3], f16(1, undefined, 2, 3), "Rest should remain unaffected when arguments is updated");
+
+        function f18(a, b = function arguments(c) {
+            if (!c) {
+                return arguments.callee(a, 10, 20);
+            }
+            return arguments;
+        }) {
+            assert.areEqual(10, b()[1], "Function defined in the param scope can be called recursively");
+            assert.areEqual(1, arguments[0], "Arguments symbol is unaffected by the function expression");
+        }
+        f18(1);
+
+        function f19(a, b = arguments) {
+            var c = function arguments(c) {
+                if (!arguments.length) {
+                    return arguments.callee(a, 10, 20, 30);
+                }
+                return arguments;
+            }
+            assert.areEqual(30, c()[3], "In the function body the arguments function expression with name is not visible");
+            assert.areEqual(1, b[0], "In the param scope arguments symbol referes to the passed in values");
+        }
+        f19(1, undefined, 2, 3, 4);
+
+        function f20(a, b = function arguments(c) {
+            if (!c) {
+                return arguments.callee(a, 10, 20);
+            }
+            return eval("arguments");
+        }) {
+            assert.areEqual(1, b()[0], "Function defined in the param scope can be called recursively when eval occurs in its body");
+            assert.areEqual(1, arguments[0], "Arguments symbol is unaffected by the function expression");
+        }
+        f20(1);
+
+        function f21(a, b = arguments) {
+            var c = function arguments(c) {
+                if (!arguments.length) {
+                    return arguments.callee(a, 10, 20, 30);
+                }
+                return arguments;
+            }
+            assert.areEqual(30, c()[3], "In the function body the arguments function expression with name is not visible when eval is there in the body");
+            assert.areEqual(3, eval("b[3]"), "In the param scope arguments symbol referes to the passed in values");
+        }
+        f21(1, undefined, 2, 3, 4);
+
+        function f22(a, b = () => a) {
+            assert.areEqual(1, arguments[0], "Function in block causes a var declaration to be hoisted and the initial value should be same as the arguments symbol");
+            {
+                {
+                    function arguments() {
+                        return 10;
+                    }
+                }
+            }
+            assert.areEqual(1, b(), "Function defined in the param scope should be able to capture the formal even when arguments in overwritten the body");
+            assert.areEqual(10, arguments(), "Hoisted var binding is updated after the block is exected");
+        }
+        f22(1);
+
+        function f23(a, b = () => a) {
+            function f16() {
+                eval("");
+                this.arguments = 1;
+            }
+
+            a = 10;
+            var obj = new f16();
+            
+            function arguments() {
+                return 10;
+            }
+            assert.areEqual(1, obj.arguments, "Inner function with eval should add the property named arguments when duplicate arguments definition occurs in the parent body");
+            assert.areEqual(1, b(), "Formal captured from the param scope should be constrained to the param scope");
+        };
+        f23(1);
     }  
   },
   {

@@ -27,6 +27,41 @@ var tests = [
             assert.throws(function() { Array.prototype.splice.call(arr, 0, 3); }, TypeError, "TypeError when constructor[Symbol.species] is not constructor", "Function 'constructor[Symbol.species]' is not a constructor");

         }

     },

+    {

+        name: "Type confusion in Array.prototype.map()",

+        body: function () {

+            function test(){

+                CollectGarbage();

+

+                var n = [];

+                for (var i = 0; i < 0x10; i++)

+                    n.push([0x12345678, 0x12345678, 0x12345678, 0x12345678]);

+

+                class fake extends Object {

+                    static get [Symbol.species]() { return function() { return n[5]; }; };

+                }

+

+                var f = function(a){ return a; }

+

+                var x = ["fluorescence", 0, 0, 0x41414141];

+                var y = new Proxy(x, {

+                    get: function(t, p, r) {

+                        return (p == "constructor") ? fake : x[p];

+                    }

+                });

+

+                // oob write

+                Array.prototype.map.apply(y, [f]);

+

+                for (var i = 0; i < 0x10; i++)

+                    n[i][0] = 0x42424242;

+

+            }

+

+            test();

+

+        }

+    },

 ];

 

 testRunner.runTests(tests, { verbose: WScript.Arguments[0] != "summary" });