Fix performance issues when parsing links

close #732
markdown-it · Nov 19, 2020 · 1198c5b · 1198c5b
1 parent 725a916
commit 1198c5b
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Showing 3 changed files with 16 additions and 2 deletions.
diff --git a/lib/helpers/parse_link_destination.js b/lib/helpers/parse_link_destination.js
@@ -22,6 +22,7 @@ module.exports = function parseLinkDestination(str, pos, max) {
     while (pos < max) {
       code = str.charCodeAt(pos);
       if (code === 0x0A /* \n */) { return result; }
+      if (code === 0x3C /* < */) { return result; }
       if (code === 0x3E /* > */) {
         result.pos = pos + 1;
         result.str = unescapeAll(str.slice(start + 1, pos));
@@ -58,6 +59,7 @@ module.exports = function parseLinkDestination(str, pos, max) {
 
     if (code === 0x28 /* ( */) {
       level++;
+      if (level > 32) { return result; }
     }
 
     if (code === 0x29 /* ) */) {

diff --git a/test/fixtures/markdown-it/commonmark_extras.txt b/test/fixtures/markdown-it/commonmark_extras.txt
@@ -255,6 +255,18 @@ List item terminating quote should not be paragraph continuation
 </ol>
 .
 
+
+Link destination cannot contain '<'
+.
+[](<foo<bar>)
+
+[](<foo\<bar>)
+.
+<p>[](&lt;foo<bar>)</p>
+<p><a href="foo%3Cbar"></a></p>
+.
+
+
 Coverage. Directive can terminate paragraph.
 .
 a

diff --git a/test/pathological.js b/test/pathological.js
@@ -121,14 +121,14 @@ describe('Pathological', function () {
     );
   });
 
-  it.skip('unclosed links A', function () {
+  it('unclosed links A', function () {
     assert.match(
       md.render('[a](<b'.repeat(30000)),
       /(\[a\]\(&lt;b){30000}/
     );
   });
 
-  it.skip('unclosed links B', function () {
+  it('unclosed links B', function () {
     assert.match(
       md.render('[a](b'.repeat(30000)),
       /(\[a\]\(b){30000}/