From 8dbd5c573eb7d4efb44e848f413f26798ff3a58b Mon Sep 17 00:00:00 2001
From: James Lal <james@silklabs.com>
Date: Thu, 31 Mar 2016 14:16:30 -0700
Subject: [PATCH] zlib: fix use after null when calling .close

An internal zlib error may cause _handle to be set to null.
Close now will check if there is a _handle prior to calling .close on
it.

PR-URL: https://github.com/nodejs/node/pull/5982
Fixes: https://github.com/nodejs/node/issues/6034
Reviewed-By: Brian White <mscdex@mscdex.net>
Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
---
 lib/zlib.js | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/lib/zlib.js b/lib/zlib.js
index 4a7c1ef153a6e1..3915e5ddabd318 100644
--- a/lib/zlib.js
+++ b/lib/zlib.js
@@ -474,7 +474,10 @@ function _close(engine, callback) {
 
   engine._closed = true;
 
-  engine._handle.close();
+  // Caller may invoke .close after a zlib error (which will null _handle).
+  if (engine._handle) {
+    engine._handle.close();
+  }
 }
 
 function emitCloseNT(self) {