Fix incorrect handling of HTML comments in messages sanitization code (#1489904)

CHANGELOG

@@ -5,6 +5,7 @@ CHANGELOG Roundcube Webmail
 - Fix unintentional draft autosave request if autosave is disabled (#1489882)
 - Fix malformed References: header in send/saved mail (#1489891)
 - Fix handling unicode characters in links (#1489898)
+- Fix incorrect handling of HTML comments in messages sanitization code (#1489904)
 
 RELEASE 1.0.1
 -------------

program/lib/Roundcube/rcube_washtml.php

@@ -456,7 +456,7 @@ class rcube_washtml
         // Remove invalid HTML comments (#1487759)
         // Don't remove valid conditional comments
         // Don't remove MSOutlook (<!-->) conditional comments (#1489004)
-        $html = preg_replace('/<!--[^->\[\n]+>/', '', $html);
+        $html = preg_replace('/<!--[^-<>\[\n]+>/', '', $html);
 
         // fix broken nested lists
         self::fix_broken_lists($html);

tests/Framework/Washtml.php

@@ -53,6 +53,16 @@ class Framework_Washtml extends PHPUnit_Framework_TestCase
         $washed = $washer->wash($html);
 
         $this->assertEquals('<!-- html ignored --><!-- body ignored --><p>test</p>', $washed, "HTML invalid comments (#1487759)");
+
+        $html   = "<p>para1</p><!-- comment --><p>para2</p>";
+        $washed = $washer->wash($html);
+
+        $this->assertEquals('<!-- html ignored --><!-- body ignored --><p>para1</p><!-- node type 8 --><p>para2</p>', $washed, "HTML comments - simple comment");
+
+        $html   = "<p>para1</p><!-- <hr> comment --><p>para2</p>";
+        $washed = $washer->wash($html);
+
+        $this->assertEquals('<!-- html ignored --><!-- body ignored --><p>para1</p><!-- node type 8 --><p>para2</p>', $washed, "HTML comments - tags inside (#1489904)");
     }
 
     /**