From 18bddeaaf225d5becfc10cd2c6a1d037c90574a2 Mon Sep 17 00:00:00 2001
From: Tomas Mraz <tmraz@fedoraproject.org>
Date: Tue, 11 Jun 2019 15:10:21 +0200
Subject: [PATCH] resolved: Fix incorrect use of OpenSSL BUF_MEM

Fixes: #12763
Upstream-Status: Backport [Not yet released]
  https://github.com/systemd/systemd/commit/18bddeaaf225d5becfc10cd2c6a1d037c90574a2
Signed-off-by: Alex Kiernan <alex.kiernan@gmail.com>
---
 src/resolve/resolved-dnstls-openssl.c | 5 ++++-
 1 file changed, 4 insertions(+), 1 deletion(-)

diff --git a/src/resolve/resolved-dnstls-openssl.c b/src/resolve/resolved-dnstls-openssl.c
index f269e4d6487f..5d9223007581 100644
--- a/src/resolve/resolved-dnstls-openssl.c
+++ b/src/resolve/resolved-dnstls-openssl.c
@@ -6,6 +6,7 @@
 
 #include <openssl/bio.h>
 #include <openssl/err.h>
+#include <string.h>
 
 #include "io-util.h"
 #include "resolved-dns-stream.h"
@@ -34,9 +35,11 @@ static int dnstls_flush_write_buffer(DnsStream *stream) {
                         return ss;
                 } else {
                         stream->dnstls_data.write_buffer->length -= ss;
-                        stream->dnstls_data.write_buffer->data += ss;
 
                         if (stream->dnstls_data.write_buffer->length > 0) {
+                                memmove(stream->dnstls_data.write_buffer->data,
+                                        stream->dnstls_data.write_buffer->data + ss,
+                                        stream->dnstls_data.write_buffer->length);
                                 stream->dnstls_events |= EPOLLOUT;
                                 return -EAGAIN;
                         }
-- 
2.17.1