From 4d5aa3923f9ae752db8a74a67e91b4d5e2239db9 Mon Sep 17 00:00:00 2001
From: Alex Gaynor <alex.gaynor@gmail.com>
Date: Wed, 21 Sep 2016 23:54:06 -0400
Subject: [PATCH] fix memory leak reported in #3134 (#3135) (#3159)

---
 src/cryptography/hazmat/backends/openssl/encode_asn1.py | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/src/cryptography/hazmat/backends/openssl/encode_asn1.py b/src/cryptography/hazmat/backends/openssl/encode_asn1.py
index 944dedc6c..467aa88eb 100644
--- a/src/cryptography/hazmat/backends/openssl/encode_asn1.py
+++ b/src/cryptography/hazmat/backends/openssl/encode_asn1.py
@@ -85,6 +85,10 @@ def _encode_name(backend, attributes):
     subject = backend._lib.X509_NAME_new()
     for attribute in attributes:
         name_entry = _encode_name_entry(backend, attribute)
+        # X509_NAME_add_entry dups the object so we need to gc this copy
+        name_entry = backend._ffi.gc(
+            name_entry, backend._lib.X509_NAME_ENTRY_free
+        )
         res = backend._lib.X509_NAME_add_entry(subject, name_entry, -1, 0)
         backend.openssl_assert(res == 1)
     return subject