misc: acoustid: fix mbz string copy

modules/misc/webservices/acoustid.c

@@ -81,7 +81,11 @@ static void parse_recordings( vlc_object_t *p_obj, json_value *node, acoustid_re
             record->psz_title = strdup( value->u.string.ptr );
         value = jsongetbyname( recordnode, "id" );
         if ( value && value->type == json_string )
-            memcpy( record->s_musicbrainz_id, value->u.string.ptr, MB_ID_SIZE );
+        {
+            size_t i_len = strlen( value->u.string.ptr );
+            i_len = __MIN( i_len, MB_ID_SIZE );
+            memcpy( record->s_musicbrainz_id, value->u.string.ptr, i_len );
+        }
         parse_artists( jsongetbyname( recordnode, "artists" ), record );
         msg_Dbg( p_obj, "recording %d title %s %36s %s", i, record->psz_title, record->s_musicbrainz_id, record->psz_artist );
     }