From 44625594591686380f6af173d565ce838ae6f245 Mon Sep 17 00:00:00 2001
From: Andrey Pozolotin <andrey.pozolotin@kyto.com>
Date: Wed, 1 Mar 2017 17:46:03 +0100
Subject: [PATCH] Fixing PREG_BACKTRACK_LIMIT_ERROR in
 HTMLPurifier_Filter_ExtractStyleBlocks

---
 library/HTMLPurifier/Filter/ExtractStyleBlocks.php | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/library/HTMLPurifier/Filter/ExtractStyleBlocks.php b/library/HTMLPurifier/Filter/ExtractStyleBlocks.php
index 08e62c16..bc5d0da2 100644
--- a/library/HTMLPurifier/Filter/ExtractStyleBlocks.php
+++ b/library/HTMLPurifier/Filter/ExtractStyleBlocks.php
@@ -95,8 +95,8 @@ class HTMLPurifier_Filter_ExtractStyleBlocks extends HTMLPurifier_Filter
         if ($tidy !== null) {
             $this->_tidy = $tidy;
         }
-        $html = preg_replace_callback('#<style(?:\s.*)?>(.+)</style>#isU', array($this, 'styleCallback'), $html);
-        $style_blocks = $this->_styleMatches;
+        $html = preg_replace_callback('#<style(?:\s.*)?>(.*)</style>#isU', array($this, 'styleCallback'), $html);
+        $style_blocks = array_filter($this->_styleMatches);
         $this->_styleMatches = array(); // reset
         $context->register('StyleBlocks', $style_blocks); // $context must not be reused
         if ($this->_tidy) {