Fix a memory leak in the mem bio

If you use a BIO and set up your own buffer that is not freed, the
memory bio will leak the BIO_BUF_MEM object it allocates.

The trouble is that the BIO_BUF_MEM is allocated and kept around,
but it is not freed if BIO_NOCLOSE is set.

The freeing of BIO_BUF_MEM was fairly confusing, simplify things
so mem_buf_free only frees the memory buffer and free the BIO_BUF_MEM
in mem_free(), where it should be done.

Alse add a test for a leak in the memory bio
Setting a memory buffer caused a leak.

Signed-off-by: Corey Minyard <minyard@acm.org>

Reviewed-by: Bernd Edlinger <bernd.edlinger@hotmail.de>
Reviewed-by: Paul Dale <paul.dale@oracle.com>
(Merged from https://github.com/openssl/openssl/pull/8051)

1 files changed, 12 insertions, 0 deletions

diff --git a/test/recipes/90-test_bio_memleak.t b/test/recipes/90-test_bio_memleak.t
new file mode 100644
index 0000000000..93f7f928a7
--- /dev/null
+++ b/test/recipes/90-test_bio_memleak.t
@@ -0,0 +1,12 @@
+#! /usr/bin/env perl
+# Copyright 2018 The OpenSSL Project Authors. All Rights Reserved.
+#
+# Licensed under the OpenSSL license (the "License").  You may not use
+# this file except in compliance with the License.  You can obtain a copy
+# in the file LICENSE in the source distribution or at
+# https://www.openssl.org/source/license.html
+
+
+use OpenSSL::Test::Simple;
+
+simple_test("test_bio_memleak", "bio_memleak_test");