Added: trunk/JSTests/stress/regexp-backref-inbounds.js (0 => 242838)
--- trunk/JSTests/stress/regexp-backref-inbounds.js (rev 0)
+++ trunk/JSTests/stress/regexp-backref-inbounds.js 2019-03-13 01:26:29 UTC (rev 242838)
@@ -0,0 +1,46 @@
+// This test should pass without crashing.
+
+function testRegExp(re, str, expected)
+{
+ let match = re.exec(str);
+
+ let errors = "";
+
+ if (match) {
+ if (!expected)
+ errors += "\nExpected no match, but got: " + match;
+ else {
+ if (match.length != expected.length)
+ errors += "\nExpected to match " + expected.length - 1 + " groups, but matched " + match.length - 1 + " groups.\n";
+ if (match[0] != expected[0])
+ errors += "\nExpected results \"" + expected[0] + "\", but got \"" + match[0] + "\"";
+
+ let checkLength = Math.min(match.length, expected.length);
+ for (i = 1; i < checkLength; ++i) {
+ if (match[i] != expected[i])
+ errors += "\nExpected group " + (i - 1) + " to be \"" + expected[i] + "\", but got \"" + match[i] + "\"";
+ }
+ }
+ } else if (expected)
+ errors += "\nExpected a match of " + expected + ", but didn't match";
+
+ if (errors.length)
+ throw errors.substring(1);
+}
+
+testRegExp(/^(.)\1*(\1.)/, " ", [" ", " ", " "]);
+testRegExp(/^(.)\1*(\1+?)a/, " ", undefined);
+
+testRegExp(/^(.)\1*?(.+)/, "xxxx", ["xxxx", "x", "xxx"]);
+
+testRegExp(/^(.{2})\1*(.+)/, "xxxx", ["xxxx", "xx", "xx"]);
+testRegExp(/^(.{2})\1*?(.+)/, "xxxx", ["xxxx", "xx", "xx"]);
+
+testRegExp(/^(.{2})\1*(.+)/, "xxx", ["xxx", "xx", "x"]);
+testRegExp(/^(.{2})\1*?(.+)/, "xxx", ["xxx", "xx", "x"]);
+
+testRegExp(/^(.)\1*(.+)/s, "=======", ["=======", "=", "="]);
+testRegExp(/^(.)\1*?(.+)/s, "=======", ["=======", "=", "======"]);
+
+testRegExp(/^(.)\1*(X)/s, "======X", ["======X", "=", "X"]);
+testRegExp(/^(.)\1*?(X)/s, "======X", ["======X", "=", "X"]);
Modified: trunk/Source/_javascript_Core/ChangeLog (242837 => 242838)
--- trunk/Source/_javascript_Core/ChangeLog 2019-03-13 01:19:20 UTC (rev 242837)
+++ trunk/Source/_javascript_Core/ChangeLog 2019-03-13 01:26:29 UTC (rev 242838)
@@ -1,3 +1,27 @@
+2019-03-12 Michael Saboff <msab...@apple.com>
+
+ REGRESSION (iOS 12.2): Webpage using CoffeeScript crashes
+ https://bugs.webkit.org/show_bug.cgi?id=195613
+
+ Reviewed by Mark Lam.
+
+ The bug here is in Yarr JIT backreference matching code. We are incorrectly
+ using a checkedOffset / inputPosition correction when checking for the available
+ length left in a string. It is improper to do these corrections as a backreference's
+ match length is based on what was matched in the referenced capture group and not
+ part of the checkedOffset and inputPosition computed when we compiled the RegExp.
+ In some cases, the resulting incorrect calculation would allow us to go past
+ the subject string's length. Removed these adjustments.
+
+ After writing tests for the first bug, found another bug where the non-greedy
+ backreference backtracking code didn't do an "are we at the end of the input?" check.
+ This caused an infinite loop as we'd jump from the backtracking code back to
+ try matching one more backreference, fail and then backtrack.
+
+ * yarr/YarrJIT.cpp:
+ (JSC::Yarr::YarrGenerator::generateBackReference):
+ (JSC::Yarr::YarrGenerator::backtrackBackReference):
+
2019-03-12 Robin Morisset <rmoris...@apple.com>
A lot more classes have padding that can be reduced by reordering their fields
Modified: trunk/Source/_javascript_Core/yarr/YarrJIT.cpp (242837 => 242838)
--- trunk/Source/_javascript_Core/yarr/YarrJIT.cpp 2019-03-13 01:19:20 UTC (rev 242837)
+++ trunk/Source/_javascript_Core/yarr/YarrJIT.cpp 2019-03-13 01:26:29 UTC (rev 242838)
@@ -1198,8 +1198,6 @@
// PatternTemp should contain pattern end index at this point
sub32(patternIndex, patternTemp);
- if (m_checkedOffset - term->inputPosition)
- sub32(Imm32((m_checkedOffset - term->inputPosition).unsafeGet()), patternTemp);
op.m_jumps.append(checkNotEnoughInput(patternTemp));
matchBackreference(opIndex, op.m_jumps, characterOrTemp, patternIndex, patternTemp);
@@ -1224,8 +1222,6 @@
// PatternTemp should contain pattern end index at this point
sub32(patternIndex, patternTemp);
- if (m_checkedOffset - term->inputPosition)
- sub32(Imm32((m_checkedOffset - term->inputPosition).unsafeGet()), patternTemp);
matches.append(checkNotEnoughInput(patternTemp));
matchBackreference(opIndex, incompleteMatches, characterOrTemp, patternIndex, patternTemp);
@@ -1270,8 +1266,6 @@
// Check if we have input remaining to match
sub32(patternIndex, patternTemp);
- if (m_checkedOffset - term->inputPosition)
- sub32(Imm32((m_checkedOffset - term->inputPosition).unsafeGet()), patternTemp);
matches.append(checkNotEnoughInput(patternTemp));
storeToFrame(index, parenthesesFrameLocation + BackTrackInfoBackReference::beginIndex());
@@ -1328,6 +1322,7 @@
case QuantifierNonGreedy: {
const RegisterID matchAmount = regT0;
+ failures.append(atEndOfInput());
loadFromFrame(parenthesesFrameLocation + BackTrackInfoBackReference::matchAmountIndex(), matchAmount);
if (term->quantityMaxCount != quantifyInfinite)
failures.append(branch32(AboveOrEqual, Imm32(term->quantityMaxCount.unsafeGet()), matchAmount));
