lkml.org 
[lkml]   [2018]   [Sep]   [13]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
    /
    Date
    From
    SubjectRe: [PATCHES] tty ioctls cleanups, compat and not only
    On Thu, Sep 13, 2018 at 03:31:19AM +0100, Al Viro wrote:
    > See vfs.git#work.tty-ioctl. Completely untested, should seriously
    > clean the things up wrt compat. Remaining problems (aside of the bugs
    > introduced in it, of course):
    > * TIOCSERGSTRUCT must die; it's present only in amiserial and it's
    > _vile_; look at what it copies out and weep.
    > * synclink_gt has proper compat handling for its private ioctls;
    > other synclink drivers (with the same ioctls) do not.
    > * dgnc definitely has buggered ioctls - structs full of longs are
    > bloody bad idea for passing around. It's in staging, and I'd say that it
    > needs the userland ABI fixed.
    > * cyclades, rocket, moxa and mxser probably have non-trivial
    > problems with their private ioctls; I hadn't looked into those.
    > * n_gsm needs ->compat_ioctl(); easy to do, I just hadn't done it
    > yet.
    > * ipwireless might or might not need compat_ioctl (PPP stuff in it);
    > not sure.
    > * ldisc private ioctls need more work. Hadn't gone there yet.
    > Generic ioctls should be fine - they never reach ->compat_ioctl() with this
    > series.
    >
    > There's some overlap with patches posted earlier - e.g. I'm fairly
    > sure that keyboard ioctl "remove from fs/compat_ioctl.c" part duplicates
    > one of yours; I'll be glad to drop and replace such duplicates with already
    > posted variants.
    >
    > Basic idea is to shunt generic ioctls that are reachable only
    > via tty_ioctl() very early in tty_compat_ioctl(), separately for those
    > that do and do not need compat_ptr(). That already simplifies the hell
    > out of ->compat_ioctl() situation - its instances won't ever see those,
    > so they can e.g. ignore the behaviour of n_tty_ioctl_helper(); whatever
    > they get in cmd won't be accepted by that one.
    >
    > Next we separate TIOC[SG]SERIAL into a couple of new methods,
    > leaving the copyin/copyout to callers. That allows to take care of
    > compat for those in tty_compat_ioctl() *and* actually kills some of
    > ->ioctl() instances.
    >
    > And then there's dead code of all kinds all over the place ;-/
    > The oldest one has been alive from Aug 1 1992 to Oct 18 1992 and had
    > shambled around ever since (FIONBIO), but there are other examples.
    > 10 years dead is better than 26, but still...
    >
    > Shortlog and diffstat follow, patches in followups...

    Thanks a lot for this work. If you and Arnd want to figure out whose
    tree to take it through, I have no objection.

    All of these can be marked as:

    Acked-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

    if you want to.

    greg k-h

    \
     
     \ /
      Last update: 2018-09-13 14:00    [W:4.187 / U:0.160 seconds]
    ©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site