Re: [PATCH 00/16] tty: TIOCSSERIAL fixes and clean ups

Greg Kroah-Hartman
2021-04-07T15:23:21Z

On Wed, Apr 07, 2021 at 12:23:18PM +0200, Johan Hovold wrote:
> TIOCSSERIAL is a horrid, underspecified, legacy interface which for most
> serial devices is only useful for setting the close_delay and
> closing_wait parameters.
>
> This series fixes up the various ways in which driver authors have
> gotten the implementation wrong over the years, like, for example,
> jiffies conversions, permissions checks and error handling.
>
> The de-facto standard for error handling is to ignore any unsupported
> features and immutable parameters (cf. UPF_FIXED_PORT and deprecated
> ASYNC flags).
>
> Permission checking should prevent an unprivileged user from changing
> anything but the ASYNC_USR flags (and custom divisor) by returning
> -EPERM.
>
> These patches are against tty-next, but the staging ones could otherwise
> go through either tree.

I've taken all of these through my tty tree, thanks for cleaning this
mess up.

greg k-h