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<dt>Revision</dt> <dd><a href="http://trac.webkit.org/projects/webkit/changeset/201412">201412</a></dd>
<dt>Author</dt> <dd>benjamin@webkit.org</dd>
<dt>Date</dt> <dd>2016-05-25 20:19:06 -0700 (Wed, 25 May 2016)</dd>
</dl>
<h3>Log Message</h3>
<pre>[JSC] RegExp with deeply nested subexpressions overflow the stack in Yarr
https://bugs.webkit.org/show_bug.cgi?id=158011
rdar://problem/25946592
Reviewed by Saam Barati.
Source/JavaScriptCore:
When generating the meta-data required for compilation,
Yarr uses a recursive function over the various expression in the pattern.
If you have many nested expressions, you can run out of stack
and crash the WebProcess.
This patch changes that into a soft failure. The expression is just
considered invalid.
* runtime/RegExp.cpp:
(JSC::RegExp::finishCreation):
(JSC::RegExp::compile):
(JSC::RegExp::compileMatchOnly):
* yarr/YarrPattern.cpp:
(JSC::Yarr::YarrPatternConstructor::YarrPatternConstructor):
(JSC::Yarr::YarrPatternConstructor::setupOffsets):
(JSC::Yarr::YarrPatternConstructor::isSafeToRecurse):
(JSC::Yarr::YarrPattern::compile):
(JSC::Yarr::YarrPattern::YarrPattern):
(JSC::Yarr::YarrPatternConstructor::setupAlternativeOffsets): Deleted.
(JSC::Yarr::YarrPatternConstructor::setupDisjunctionOffsets): Deleted.
* yarr/YarrPattern.h:
LayoutTests:
* js/script-tests/stack-overflow-arrity-catch.js:
With the new failure, this test can fail on allocating
the RegExp for a valid reason.
The new expression should not have this issue.
* js/script-tests/stack-overflow-regexp.js: Added.
(shouldThrow.recursiveCall):
(shouldThrow):
(recursiveCall):
* js/stack-overflow-regexp-expected.txt: Added.
* js/stack-overflow-regexp.html: Added.</pre>
<h3>Modified Paths</h3>
<ul>
<li><a href="#trunkLayoutTestsChangeLog">trunk/LayoutTests/ChangeLog</a></li>
<li><a href="#trunkLayoutTestsjsscripttestsstackoverflowarritycatchjs">trunk/LayoutTests/js/script-tests/stack-overflow-arrity-catch.js</a></li>
<li><a href="#trunkSourceJavaScriptCoreChangeLog">trunk/Source/JavaScriptCore/ChangeLog</a></li>
<li><a href="#trunkSourceJavaScriptCoreruntimeRegExpcpp">trunk/Source/JavaScriptCore/runtime/RegExp.cpp</a></li>
<li><a href="#trunkSourceJavaScriptCoreyarrYarrPatterncpp">trunk/Source/JavaScriptCore/yarr/YarrPattern.cpp</a></li>
<li><a href="#trunkSourceJavaScriptCoreyarrYarrPatternh">trunk/Source/JavaScriptCore/yarr/YarrPattern.h</a></li>
</ul>
<h3>Added Paths</h3>
<ul>
<li><a href="#trunkLayoutTestsjsscripttestsstackoverflowregexpjs">trunk/LayoutTests/js/script-tests/stack-overflow-regexp.js</a></li>
<li><a href="#trunkLayoutTestsjsstackoverflowregexpexpectedtxt">trunk/LayoutTests/js/stack-overflow-regexp-expected.txt</a></li>
<li><a href="#trunkLayoutTestsjsstackoverflowregexphtml">trunk/LayoutTests/js/stack-overflow-regexp.html</a></li>
</ul>
</div>
<div id="patch">
<h3>Diff</h3>
<a id="trunkLayoutTestsChangeLog"></a>
<div class="modfile"><h4>Modified: trunk/LayoutTests/ChangeLog (201411 => 201412)</h4>
<pre class="diff"><span>
<span class="info">--- trunk/LayoutTests/ChangeLog 2016-05-26 00:08:48 UTC (rev 201411)
+++ trunk/LayoutTests/ChangeLog 2016-05-26 03:19:06 UTC (rev 201412)
</span><span class="lines">@@ -1,3 +1,23 @@
</span><ins>+2016-05-25 Benjamin Poulain <benjamin@webkit.org>
+
+ [JSC] RegExp with deeply nested subexpressions overflow the stack in Yarr
+ https://bugs.webkit.org/show_bug.cgi?id=158011
+ rdar://problem/25946592
+
+ Reviewed by Saam Barati.
+
+ * js/script-tests/stack-overflow-arrity-catch.js:
+ With the new failure, this test can fail on allocating
+ the RegExp for a valid reason.
+
+ The new expression should not have this issue.
+ * js/script-tests/stack-overflow-regexp.js: Added.
+ (shouldThrow.recursiveCall):
+ (shouldThrow):
+ (recursiveCall):
+ * js/stack-overflow-regexp-expected.txt: Added.
+ * js/stack-overflow-regexp.html: Added.
+
</ins><span class="cx"> 2016-05-25 Ryan Haddad <ryanhaddad@apple.com>
</span><span class="cx">
</span><span class="cx"> Marking imported/blink/http/tests/plugins/get-url-notify-on-removal.html as a flaky timeout
</span></span></pre></div>
<a id="trunkLayoutTestsjsscripttestsstackoverflowarritycatchjs"></a>
<div class="modfile"><h4>Modified: trunk/LayoutTests/js/script-tests/stack-overflow-arrity-catch.js (201411 => 201412)</h4>
<pre class="diff"><span>
<span class="info">--- trunk/LayoutTests/js/script-tests/stack-overflow-arrity-catch.js 2016-05-26 00:08:48 UTC (rev 201411)
+++ trunk/LayoutTests/js/script-tests/stack-overflow-arrity-catch.js 2016-05-26 03:19:06 UTC (rev 201412)
</span><span class="lines">@@ -17,7 +17,7 @@
</span><span class="cx"> // Should get here because of stack overflow,
</span><span class="cx"> // now cause a stack overflow exception due to arrity processing
</span><span class="cx"> try {
</span><del>- var dummy = new RegExp('a|b|c');
</del><ins>+ var dummy = new Float64Array(128);
</ins><span class="cx"> } catch(err) {
</span><span class="cx"> gotWrongCatch1 = true;
</span><span class="cx"> }
</span></span></pre></div>
<a id="trunkLayoutTestsjsscripttestsstackoverflowregexpjs"></a>
<div class="addfile"><h4>Added: trunk/LayoutTests/js/script-tests/stack-overflow-regexp.js (0 => 201412)</h4>
<pre class="diff"><span>
<span class="info">--- trunk/LayoutTests/js/script-tests/stack-overflow-regexp.js (rev 0)
+++ trunk/LayoutTests/js/script-tests/stack-overflow-regexp.js 2016-05-26 03:19:06 UTC (rev 201412)
</span><span class="lines">@@ -0,0 +1,29 @@
</span><ins>+description('Test that we do not overflow the stack while handling regular expressions');
+
+// Base case.
+shouldThrow('new RegExp(Array(50000).join("(") + "a" + Array(50000).join(")"))', '"SyntaxError: Invalid regular expression: too many nested disjunctions"');
+
+{ // Verify that a deep JS stack does not help avoiding the error.
+ function recursiveCall(depth) {
+ if (!(depth % 10)) {
+ debug("Creating RegExp at depth " + depth);
+ shouldThrow('new RegExp(Array(50000).join("(") + "a" + Array(50000).join(")"))', '"SyntaxError: Invalid regular expression: too many nested disjunctions"');
+ }
+ if (depth < 100) {
+ recursiveCall(depth + 1);
+ }
+ }
+ recursiveCall(0);
+}
+
+{ // Have the deepest nested subpattern surrounded by other expressions.
+ var expression = "";
+ for (let i = 0; i < 50000; ++i) {
+ expression += "((a)(";
+ }
+ expression += "b";
+ for (let i = 0; i < 50000; ++i) {
+ expression += ")(c))";
+ }
+ shouldThrow('new RegExp(expression)', '"SyntaxError: Invalid regular expression: too many nested disjunctions"');
+}
</ins></span></pre></div>
<a id="trunkLayoutTestsjsstackoverflowregexpexpectedtxt"></a>
<div class="addfile"><h4>Added: trunk/LayoutTests/js/stack-overflow-regexp-expected.txt (0 => 201412)</h4>
<pre class="diff"><span>
<span class="info">--- trunk/LayoutTests/js/stack-overflow-regexp-expected.txt (rev 0)
+++ trunk/LayoutTests/js/stack-overflow-regexp-expected.txt 2016-05-26 03:19:06 UTC (rev 201412)
</span><span class="lines">@@ -0,0 +1,33 @@
</span><ins>+Test that we do not overflow the stack while handling regular expressions
+
+On success, you will see a series of "PASS" messages, followed by "TEST COMPLETE".
+
+
+PASS new RegExp(Array(50000).join("(") + "a" + Array(50000).join(")")) threw exception SyntaxError: Invalid regular expression: too many nested disjunctions.
+Creating RegExp at depth 0
+PASS new RegExp(Array(50000).join("(") + "a" + Array(50000).join(")")) threw exception SyntaxError: Invalid regular expression: too many nested disjunctions.
+Creating RegExp at depth 10
+PASS new RegExp(Array(50000).join("(") + "a" + Array(50000).join(")")) threw exception SyntaxError: Invalid regular expression: too many nested disjunctions.
+Creating RegExp at depth 20
+PASS new RegExp(Array(50000).join("(") + "a" + Array(50000).join(")")) threw exception SyntaxError: Invalid regular expression: too many nested disjunctions.
+Creating RegExp at depth 30
+PASS new RegExp(Array(50000).join("(") + "a" + Array(50000).join(")")) threw exception SyntaxError: Invalid regular expression: too many nested disjunctions.
+Creating RegExp at depth 40
+PASS new RegExp(Array(50000).join("(") + "a" + Array(50000).join(")")) threw exception SyntaxError: Invalid regular expression: too many nested disjunctions.
+Creating RegExp at depth 50
+PASS new RegExp(Array(50000).join("(") + "a" + Array(50000).join(")")) threw exception SyntaxError: Invalid regular expression: too many nested disjunctions.
+Creating RegExp at depth 60
+PASS new RegExp(Array(50000).join("(") + "a" + Array(50000).join(")")) threw exception SyntaxError: Invalid regular expression: too many nested disjunctions.
+Creating RegExp at depth 70
+PASS new RegExp(Array(50000).join("(") + "a" + Array(50000).join(")")) threw exception SyntaxError: Invalid regular expression: too many nested disjunctions.
+Creating RegExp at depth 80
+PASS new RegExp(Array(50000).join("(") + "a" + Array(50000).join(")")) threw exception SyntaxError: Invalid regular expression: too many nested disjunctions.
+Creating RegExp at depth 90
+PASS new RegExp(Array(50000).join("(") + "a" + Array(50000).join(")")) threw exception SyntaxError: Invalid regular expression: too many nested disjunctions.
+Creating RegExp at depth 100
+PASS new RegExp(Array(50000).join("(") + "a" + Array(50000).join(")")) threw exception SyntaxError: Invalid regular expression: too many nested disjunctions.
+PASS new RegExp(expression) threw exception SyntaxError: Invalid regular expression: too many nested disjunctions.
+PASS successfullyParsed is true
+
+TEST COMPLETE
+
</ins></span></pre></div>
<a id="trunkLayoutTestsjsstackoverflowregexphtml"></a>
<div class="addfile"><h4>Added: trunk/LayoutTests/js/stack-overflow-regexp.html (0 => 201412)</h4>
<pre class="diff"><span>
<span class="info">--- trunk/LayoutTests/js/stack-overflow-regexp.html (rev 0)
+++ trunk/LayoutTests/js/stack-overflow-regexp.html 2016-05-26 03:19:06 UTC (rev 201412)
</span><span class="lines">@@ -0,0 +1,10 @@
</span><ins>+<!DOCTYPE HTML PUBLIC "-//IETF//DTD HTML//EN">
+<html>
+<head>
+<script src="../resources/js-test-pre.js"></script>
+</head>
+<body>
+<script src="script-tests/stack-overflow-regexp.js "></script>
+<script src="../resources/js-test-post.js"></script>
+</body>
+</html>
</ins></span></pre></div>
<a id="trunkSourceJavaScriptCoreChangeLog"></a>
<div class="modfile"><h4>Modified: trunk/Source/JavaScriptCore/ChangeLog (201411 => 201412)</h4>
<pre class="diff"><span>
<span class="info">--- trunk/Source/JavaScriptCore/ChangeLog 2016-05-26 00:08:48 UTC (rev 201411)
+++ trunk/Source/JavaScriptCore/ChangeLog 2016-05-26 03:19:06 UTC (rev 201412)
</span><span class="lines">@@ -1,3 +1,33 @@
</span><ins>+2016-05-25 Benjamin Poulain <benjamin@webkit.org>
+
+ [JSC] RegExp with deeply nested subexpressions overflow the stack in Yarr
+ https://bugs.webkit.org/show_bug.cgi?id=158011
+ rdar://problem/25946592
+
+ Reviewed by Saam Barati.
+
+ When generating the meta-data required for compilation,
+ Yarr uses a recursive function over the various expression in the pattern.
+
+ If you have many nested expressions, you can run out of stack
+ and crash the WebProcess.
+ This patch changes that into a soft failure. The expression is just
+ considered invalid.
+
+ * runtime/RegExp.cpp:
+ (JSC::RegExp::finishCreation):
+ (JSC::RegExp::compile):
+ (JSC::RegExp::compileMatchOnly):
+ * yarr/YarrPattern.cpp:
+ (JSC::Yarr::YarrPatternConstructor::YarrPatternConstructor):
+ (JSC::Yarr::YarrPatternConstructor::setupOffsets):
+ (JSC::Yarr::YarrPatternConstructor::isSafeToRecurse):
+ (JSC::Yarr::YarrPattern::compile):
+ (JSC::Yarr::YarrPattern::YarrPattern):
+ (JSC::Yarr::YarrPatternConstructor::setupAlternativeOffsets): Deleted.
+ (JSC::Yarr::YarrPatternConstructor::setupDisjunctionOffsets): Deleted.
+ * yarr/YarrPattern.h:
+
</ins><span class="cx"> 2016-05-25 Alex Christensen <achristensen@webkit.org>
</span><span class="cx">
</span><span class="cx"> Fix Win64 build after r201335
</span></span></pre></div>
<a id="trunkSourceJavaScriptCoreruntimeRegExpcpp"></a>
<div class="modfile"><h4>Modified: trunk/Source/JavaScriptCore/runtime/RegExp.cpp (201411 => 201412)</h4>
<pre class="diff"><span>
<span class="info">--- trunk/Source/JavaScriptCore/runtime/RegExp.cpp 2016-05-26 00:08:48 UTC (rev 201411)
+++ trunk/Source/JavaScriptCore/runtime/RegExp.cpp 2016-05-26 03:19:06 UTC (rev 201412)
</span><span class="lines">@@ -222,7 +222,7 @@
</span><span class="cx"> void RegExp::finishCreation(VM& vm)
</span><span class="cx"> {
</span><span class="cx"> Base::finishCreation(vm);
</span><del>- Yarr::YarrPattern pattern(m_patternString, m_flags, &m_constructionError);
</del><ins>+ Yarr::YarrPattern pattern(m_patternString, m_flags, &m_constructionError, vm.stackLimit());
</ins><span class="cx"> if (m_constructionError)
</span><span class="cx"> m_state = ParseError;
</span><span class="cx"> else
</span><span class="lines">@@ -264,7 +264,7 @@
</span><span class="cx"> {
</span><span class="cx"> ConcurrentJITLocker locker(m_lock);
</span><span class="cx">
</span><del>- Yarr::YarrPattern pattern(m_patternString, m_flags, &m_constructionError);
</del><ins>+ Yarr::YarrPattern pattern(m_patternString, m_flags, &m_constructionError, vm->stackLimit());
</ins><span class="cx"> if (m_constructionError) {
</span><span class="cx"> RELEASE_ASSERT_NOT_REACHED();
</span><span class="cx"> #if COMPILER_QUIRK(CONSIDERS_UNREACHABLE_CODE)
</span><span class="lines">@@ -317,7 +317,7 @@
</span><span class="cx"> {
</span><span class="cx"> ConcurrentJITLocker locker(m_lock);
</span><span class="cx">
</span><del>- Yarr::YarrPattern pattern(m_patternString, m_flags, &m_constructionError);
</del><ins>+ Yarr::YarrPattern pattern(m_patternString, m_flags, &m_constructionError, vm->stackLimit());
</ins><span class="cx"> if (m_constructionError) {
</span><span class="cx"> RELEASE_ASSERT_NOT_REACHED();
</span><span class="cx"> #if COMPILER_QUIRK(CONSIDERS_UNREACHABLE_CODE)
</span></span></pre></div>
<a id="trunkSourceJavaScriptCoreyarrYarrPatterncpp"></a>
<div class="modfile"><h4>Modified: trunk/Source/JavaScriptCore/yarr/YarrPattern.cpp (201411 => 201412)</h4>
<pre class="diff"><span>
<span class="info">--- trunk/Source/JavaScriptCore/yarr/YarrPattern.cpp 2016-05-26 00:08:48 UTC (rev 201411)
+++ trunk/Source/JavaScriptCore/yarr/YarrPattern.cpp 2016-05-26 03:19:06 UTC (rev 201412)
</span><span class="lines">@@ -31,6 +31,7 @@
</span><span class="cx"> #include "YarrCanonicalize.h"
</span><span class="cx"> #include "YarrParser.h"
</span><span class="cx"> #include <wtf/Vector.h>
</span><ins>+#include <wtf/WTFThreadData.h>
</ins><span class="cx">
</span><span class="cx"> using namespace WTF;
</span><span class="cx">
</span><span class="lines">@@ -274,9 +275,10 @@
</span><span class="cx">
</span><span class="cx"> class YarrPatternConstructor {
</span><span class="cx"> public:
</span><del>- YarrPatternConstructor(YarrPattern& pattern)
</del><ins>+ YarrPatternConstructor(YarrPattern& pattern, void* stackLimit)
</ins><span class="cx"> : m_pattern(pattern)
</span><span class="cx"> , m_characterClassConstructor(pattern.ignoreCase(), pattern.unicode() ? CanonicalMode::Unicode : CanonicalMode::UCS2)
</span><ins>+ , m_stackLimit(stackLimit)
</ins><span class="cx"> , m_invertParentheticalAssertion(false)
</span><span class="cx"> {
</span><span class="cx"> auto body = std::make_unique<PatternDisjunction>();
</span><span class="lines">@@ -579,8 +581,11 @@
</span><span class="cx"> m_alternative = m_alternative->m_parent->addNewAlternative();
</span><span class="cx"> }
</span><span class="cx">
</span><del>- unsigned setupAlternativeOffsets(PatternAlternative* alternative, unsigned currentCallFrameSize, unsigned initialInputPosition)
</del><ins>+ bool setupAlternativeOffsets(PatternAlternative* alternative, unsigned currentCallFrameSize, unsigned initialInputPosition, unsigned& newCallFrameSize) WARN_UNUSED_RETURN
</ins><span class="cx"> {
</span><ins>+ if (!isSafeToRecurse())
+ return false;
+
</ins><span class="cx"> alternative->m_hasFixedSize = true;
</span><span class="cx"> Checked<unsigned> currentInputPosition = initialInputPosition;
</span><span class="cx">
</span><span class="lines">@@ -637,18 +642,22 @@
</span><span class="cx"> if (term.quantityCount == 1 && !term.parentheses.isCopy) {
</span><span class="cx"> if (term.quantityType != QuantifierFixedCount)
</span><span class="cx"> currentCallFrameSize += YarrStackSpaceForBackTrackInfoParenthesesOnce;
</span><del>- currentCallFrameSize = setupDisjunctionOffsets(term.parentheses.disjunction, currentCallFrameSize, currentInputPosition.unsafeGet());
</del><ins>+ if (!setupDisjunctionOffsets(term.parentheses.disjunction, currentCallFrameSize, currentInputPosition.unsafeGet(), currentCallFrameSize))
+ return false;
</ins><span class="cx"> // If quantity is fixed, then pre-check its minimum size.
</span><span class="cx"> if (term.quantityType == QuantifierFixedCount)
</span><span class="cx"> currentInputPosition += term.parentheses.disjunction->m_minimumSize;
</span><span class="cx"> term.inputPosition = currentInputPosition.unsafeGet();
</span><span class="cx"> } else if (term.parentheses.isTerminal) {
</span><span class="cx"> currentCallFrameSize += YarrStackSpaceForBackTrackInfoParenthesesTerminal;
</span><del>- currentCallFrameSize = setupDisjunctionOffsets(term.parentheses.disjunction, currentCallFrameSize, currentInputPosition.unsafeGet());
</del><ins>+ if (!setupDisjunctionOffsets(term.parentheses.disjunction, currentCallFrameSize, currentInputPosition.unsafeGet(), currentCallFrameSize))
+ return false;
</ins><span class="cx"> term.inputPosition = currentInputPosition.unsafeGet();
</span><span class="cx"> } else {
</span><span class="cx"> term.inputPosition = currentInputPosition.unsafeGet();
</span><del>- setupDisjunctionOffsets(term.parentheses.disjunction, 0, currentInputPosition.unsafeGet());
</del><ins>+ unsigned ignoredCallFrameSize;
+ if (!setupDisjunctionOffsets(term.parentheses.disjunction, 0, currentInputPosition.unsafeGet(), ignoredCallFrameSize))
+ return false;
</ins><span class="cx"> currentCallFrameSize += YarrStackSpaceForBackTrackInfoParentheses;
</span><span class="cx"> }
</span><span class="cx"> // Fixed count of 1 could be accepted, if they have a fixed size *AND* if all alternatives are of the same length.
</span><span class="lines">@@ -658,7 +667,8 @@
</span><span class="cx"> case PatternTerm::TypeParentheticalAssertion:
</span><span class="cx"> term.inputPosition = currentInputPosition.unsafeGet();
</span><span class="cx"> term.frameLocation = currentCallFrameSize;
</span><del>- currentCallFrameSize = setupDisjunctionOffsets(term.parentheses.disjunction, currentCallFrameSize + YarrStackSpaceForBackTrackInfoParentheticalAssertion, currentInputPosition.unsafeGet());
</del><ins>+ if (!setupDisjunctionOffsets(term.parentheses.disjunction, currentCallFrameSize + YarrStackSpaceForBackTrackInfoParentheticalAssertion, currentInputPosition.unsafeGet(), currentCallFrameSize))
+ return false;
</ins><span class="cx"> break;
</span><span class="cx">
</span><span class="cx"> case PatternTerm::TypeDotStarEnclosure:
</span><span class="lines">@@ -669,11 +679,15 @@
</span><span class="cx"> }
</span><span class="cx">
</span><span class="cx"> alternative->m_minimumSize = (currentInputPosition - initialInputPosition).unsafeGet();
</span><del>- return currentCallFrameSize;
</del><ins>+ newCallFrameSize = currentCallFrameSize;
+ return true;
</ins><span class="cx"> }
</span><span class="cx">
</span><del>- unsigned setupDisjunctionOffsets(PatternDisjunction* disjunction, unsigned initialCallFrameSize, unsigned initialInputPosition)
</del><ins>+ bool setupDisjunctionOffsets(PatternDisjunction* disjunction, unsigned initialCallFrameSize, unsigned initialInputPosition, unsigned& callFrameSize) WARN_UNUSED_RETURN
</ins><span class="cx"> {
</span><ins>+ if (!isSafeToRecurse())
+ return false;
+
</ins><span class="cx"> if ((disjunction != m_pattern.m_body) && (disjunction->m_alternatives.size() > 1))
</span><span class="cx"> initialCallFrameSize += YarrStackSpaceForBackTrackInfoAlternative;
</span><span class="cx">
</span><span class="lines">@@ -683,7 +697,9 @@
</span><span class="cx">
</span><span class="cx"> for (unsigned alt = 0; alt < disjunction->m_alternatives.size(); ++alt) {
</span><span class="cx"> PatternAlternative* alternative = disjunction->m_alternatives[alt].get();
</span><del>- unsigned currentAlternativeCallFrameSize = setupAlternativeOffsets(alternative, initialCallFrameSize, initialInputPosition);
</del><ins>+ unsigned currentAlternativeCallFrameSize;
+ if (!setupAlternativeOffsets(alternative, initialCallFrameSize, initialInputPosition, currentAlternativeCallFrameSize))
+ return false;
</ins><span class="cx"> minimumInputSize = std::min(minimumInputSize, alternative->m_minimumSize);
</span><span class="cx"> maximumCallFrameSize = std::max(maximumCallFrameSize, currentAlternativeCallFrameSize);
</span><span class="cx"> hasFixedSize &= alternative->m_hasFixedSize;
</span><span class="lines">@@ -697,12 +713,17 @@
</span><span class="cx"> disjunction->m_hasFixedSize = hasFixedSize;
</span><span class="cx"> disjunction->m_minimumSize = minimumInputSize;
</span><span class="cx"> disjunction->m_callFrameSize = maximumCallFrameSize;
</span><del>- return maximumCallFrameSize;
</del><ins>+ callFrameSize = maximumCallFrameSize;
+ return true;
</ins><span class="cx"> }
</span><span class="cx">
</span><del>- void setupOffsets()
</del><ins>+ const char* setupOffsets()
</ins><span class="cx"> {
</span><del>- setupDisjunctionOffsets(m_pattern.m_body, 0, 0);
</del><ins>+ // FIXME: Yarr should not use the stack to handle subpatterns (rdar://problem/26436314).
+ unsigned ignoredCallFrameSize;
+ if (!setupDisjunctionOffsets(m_pattern.m_body, 0, 0, ignoredCallFrameSize))
+ return REGEXP_ERROR_PREFIX "too many nested disjunctions";
+ return nullptr;
</ins><span class="cx"> }
</span><span class="cx">
</span><span class="cx"> // This optimization identifies sets of parentheses that we will never need to backtrack.
</span><span class="lines">@@ -842,16 +863,27 @@
</span><span class="cx"> }
</span><span class="cx">
</span><span class="cx"> private:
</span><ins>+ bool isSafeToRecurse() const
+ {
+ if (!m_stackLimit)
+ return true;
+ ASSERT(wtfThreadData().stack().isGrowingDownward());
+ int8_t* curr = reinterpret_cast<int8_t*>(&curr);
+ int8_t* limit = reinterpret_cast<int8_t*>(m_stackLimit);
+ return curr >= limit;
+ }
+
</ins><span class="cx"> YarrPattern& m_pattern;
</span><span class="cx"> PatternAlternative* m_alternative;
</span><span class="cx"> CharacterClassConstructor m_characterClassConstructor;
</span><ins>+ void* m_stackLimit;
</ins><span class="cx"> bool m_invertCharacterClass;
</span><span class="cx"> bool m_invertParentheticalAssertion;
</span><span class="cx"> };
</span><span class="cx">
</span><del>-const char* YarrPattern::compile(const String& patternString)
</del><ins>+const char* YarrPattern::compile(const String& patternString, void* stackLimit)
</ins><span class="cx"> {
</span><del>- YarrPatternConstructor constructor(*this);
</del><ins>+ YarrPatternConstructor constructor(*this, stackLimit);
</ins><span class="cx">
</span><span class="cx"> if (const char* error = parse(constructor, patternString, unicode()))
</span><span class="cx"> return error;
</span><span class="lines">@@ -877,12 +909,13 @@
</span><span class="cx"> constructor.optimizeDotStarWrappedExpressions();
</span><span class="cx"> constructor.optimizeBOL();
</span><span class="cx">
</span><del>- constructor.setupOffsets();
</del><ins>+ if (const char* error = constructor.setupOffsets())
+ return error;
</ins><span class="cx">
</span><del>- return 0;
</del><ins>+ return nullptr;
</ins><span class="cx"> }
</span><span class="cx">
</span><del>-YarrPattern::YarrPattern(const String& pattern, RegExpFlags flags, const char** error)
</del><ins>+YarrPattern::YarrPattern(const String& pattern, RegExpFlags flags, const char** error, void* stackLimit)
</ins><span class="cx"> : m_containsBackreferences(false)
</span><span class="cx"> , m_containsBOL(false)
</span><span class="cx"> , m_containsUnsignedLengthPattern(false)
</span><span class="lines">@@ -899,7 +932,7 @@
</span><span class="cx"> , nonwordcharCached(0)
</span><span class="cx"> , nonwordUnicodeIgnoreCasecharCached(0)
</span><span class="cx"> {
</span><del>- *error = compile(pattern);
</del><ins>+ *error = compile(pattern, stackLimit);
</ins><span class="cx"> }
</span><span class="cx">
</span><span class="cx"> } }
</span></span></pre></div>
<a id="trunkSourceJavaScriptCoreyarrYarrPatternh"></a>
<div class="modfile"><h4>Modified: trunk/Source/JavaScriptCore/yarr/YarrPattern.h (201411 => 201412)</h4>
<pre class="diff"><span>
<span class="info">--- trunk/Source/JavaScriptCore/yarr/YarrPattern.h 2016-05-26 00:08:48 UTC (rev 201411)
+++ trunk/Source/JavaScriptCore/yarr/YarrPattern.h 2016-05-26 03:19:06 UTC (rev 201412)
</span><span class="lines">@@ -304,7 +304,7 @@
</span><span class="cx">
</span><span class="cx">
</span><span class="cx"> struct YarrPattern {
</span><del>- JS_EXPORT_PRIVATE YarrPattern(const String& pattern, RegExpFlags flags, const char** error);
</del><ins>+ JS_EXPORT_PRIVATE YarrPattern(const String& pattern, RegExpFlags, const char** error, void* stackLimit = nullptr);
</ins><span class="cx">
</span><span class="cx"> void reset()
</span><span class="cx"> {
</span><span class="lines">@@ -428,7 +428,7 @@
</span><span class="cx"> Vector<std::unique_ptr<CharacterClass>> m_userCharacterClasses;
</span><span class="cx">
</span><span class="cx"> private:
</span><del>- const char* compile(const String& patternString);
</del><ins>+ const char* compile(const String& patternString, void* stackLimit);
</ins><span class="cx">
</span><span class="cx"> CharacterClass* newlineCached;
</span><span class="cx"> CharacterClass* digitsCached;
</span></span></pre>
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