matroska-demux: Make sure that subtitle buffers are \0-terminated

https://bugzilla.gnome.org/show_bug.cgi?id=707933

diff --git a/gst/matroska/matroska-demux.c b/gst/matroska/matroska-demux.c
index d5d705e..d7b8901 100644 (file)
--- a/gst/matroska/matroska-demux.c
+++ b/gst/matroska/matroska-demux.c
@@ -3060,6 +3060,23 @@ gst_matroska_demux_check_subtitle_buffer (GstElement * element,
   gst_buffer_map (*buf, &map, GST_MAP_READ);
 
 next:
+  /* Need \0-terminator at the end */
+  if (map.data[map.size - 1] != '\0') {
+    newbuf = gst_buffer_new_and_alloc (map.size + 1);
+
+    /* Copy old buffer and add a 0 at the end */
+    gst_buffer_fill (newbuf, 0, map.data, map.size);
+    gst_buffer_memset (newbuf, map.size, 0, 1);
+    gst_buffer_unmap (*buf, &map);
+
+    gst_buffer_copy_into (newbuf, *buf,
+        GST_BUFFER_COPY_TIMESTAMPS | GST_BUFFER_COPY_FLAGS |
+        GST_BUFFER_COPY_META, 0, -1);
+    gst_buffer_unref (*buf);
+    *buf = newbuf;
+    gst_buffer_map (*buf, &map, GST_MAP_READ);
+  }
+
   if (sub_stream->check_markup) {
     /* caps claim markup text, so we need to escape text,
      * except if text is already markup and then needs no further escaping */