Description:
------------
In the php_stream_url_wrap_ftp function in ext/standard/ftp_fopen_wrapper.c, the tmp_line local variable is used for two distinct purposes:

1) parsing SIZE response

    php_stream_notify_file_size(context, file_size, tmp_line, result);

2) constructing RETR/STOR/APPE request

    memcpy(tmp_line, "RETR", sizeof("RETR"));
    ...

When the function fails (jumps to errexit) the tmp_line variable is used to construct an error message:

    php_stream_wrapper_log_error(wrapper, options, "FTP server reports %s", tmp_line);

So when the function fails only after the tmp_line is reused for purpose 2), like when a data connection cannot be opened, the error message is nonsense like:

> failed to open stream: FTP server reports STOR

I'm reporting this based on this http://stackoverflow.com/q/40415540/850848

The error is present at least since PHP 5.5, up to the PHP 7.0.12.