From 0537dd2c55fef7ed954fd991ad526bbcbc4be8d0 Mon Sep 17 00:00:00 2001
From: Marcel Greter <marcel.greter@ocbnet.ch>
Date: Wed, 23 Oct 2019 19:55:20 +0200
Subject: [PATCH] Fix possible memory leak in permutation function

Fixes https://github.com/sass/libsass/issues/3014
---
 src/permutate.hpp | 10 +++++++---
 1 file changed, 7 insertions(+), 3 deletions(-)

diff --git a/src/permutate.hpp b/src/permutate.hpp
index 2b83d02f5..01077940c 100644
--- a/src/permutate.hpp
+++ b/src/permutate.hpp
@@ -22,14 +22,18 @@ namespace Sass {
     const std::vector<std::vector<T>>& in)
   {
 
-    size_t L = in.size();
-    size_t n = 0;
+    size_t L = in.size(), n = 0;
+
+    // Exit early if any entry is empty
+    for (size_t i = 0; i < L; i += 1) {
+      if (in[i].size() == 0) return {};
+    }
+
     size_t* state = new size_t[L + 1];
     std::vector<std::vector<T>> out;
 
     // First initialize all states for every permutation group
     for (size_t i = 0; i < L; i += 1) {
-      if (in[i].size() == 0) return {};
       state[i] = in[i].size() - 1;
     }
     while (true) {