Re: [PATCH] Cygwin: pty: Prevent potential errno overwriting.

[Corinna Vinschen <corinna-cygwin at cygwin dot com>]

On Feb 10 20:42, Takashi Yano wrote:
> - In push_to_pcon_screenbuffer(), open() and ioctl() are called.
>   Since push_to_pcon_screenbuffer() is called in read() and write(),
>   errno which is set in read() and write() code may be overwritten
>   in open() or ioctl() call. This patch prevent this situation.
> ---
>  winsup/cygwin/fhandler_tty.cc | 3 +++
>  1 file changed, 3 insertions(+)
> 
> diff --git a/winsup/cygwin/fhandler_tty.cc b/winsup/cygwin/fhandler_tty.cc
> index 260776a56..cfd4b1c44 100644
> --- a/winsup/cygwin/fhandler_tty.cc
> +++ b/winsup/cygwin/fhandler_tty.cc
> @@ -1412,10 +1412,13 @@ fhandler_pty_slave::push_to_pcon_screenbuffer (const char *ptr, size_t len,
>    while (!GetConsoleMode (get_output_handle (), &dwMode))
>      {
>        termios_printf ("GetConsoleMode failed, %E");
> +      int errno_save = errno;
>        /* Re-open handles */
>        this->open (0, 0);
>        /* Fix pseudo console window size */
>        this->ioctl (TIOCSWINSZ, &get_ttyp ()->winsize);
> +      if (errno != errno_save)
> +	set_errno (errno_save);
>        if (++retry_count > 3)
>  	goto cleanup;
>      }
> -- 
> 2.21.0


Pushed.


Thanks,
Corinna

-- 
Corinna Vinschen
Cygwin Maintainer

Attachment: signature.asc
Description: PGP signature