Re: [PATCH 46/50] vt_compat_ioctl(): clean up, use compat_ptr() properly

[Arnd Bergmann]

On Thu, Sep 13, 2018 at 4:42 AM Al Viro <viro@xxxxxxxxxxxxxxxxxx> wrote:
>
> From: Al Viro <viro@xxxxxxxxxxxxxxxxxx>
>
> we need it for "convert the structure" cases too
>
> Signed-off-by: Al Viro <viro@xxxxxxxxxxxxxxxxxx>

Nice catch. I introduced the mistake in commit
e92166517e3c ("tty: handle VT specific compat ioctls in vt driver"),
the original code was fine. drivers/s390/char/tty3270.c implements
some of the VT ioctls, but none that are affected by this.

At least the VT code is not usable on s390, so it did not make
a practical difference.

        Arnd