Date: Sat, 3 Jun 2017 09:32:55 +0200
From: Adam Borowski <kilobyte@angband.pl>
To: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
        Jiri Slaby <jslaby@suse.com>, linux-kernel@vger.kernel.org
Subject: [PATCH 0/5] vt: get rid of worst cases of __put_user/__get_user
Message-ID: <20170603073255.zgpfmdp2pqusz4qw@angband.pl>
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Hi!
In a recent discussion, Linus and Al Viro said quite a bit of expletives
about __put_user() and __get_user(), that it's a bad interface that's
almost always the wrong thing to use:
https://marc.info/?l=linux-kernel&m=149463725626316&w=2
https://marc.info/?l=linux-kernel&m=149465866929092&w=2

Here's a few patches applying the lessons from that discussion to vt.
None of the uses is performance-critical, but at least we get a nice bit
of code simplification.  And, it's a start of manual review + conversion
that Al Viro wants.


Adam Borowski (5):
      vt: use copy_from/to_user instead of __get/put_user for scrnmap ioctls
      vt: fix unchecked __put_user() in tioclinux ioctls
      vt: use copy_to_user instead of __put_user in GIO_UNIMAP ioctl
      vt: use memdup_user in PIO_UNIMAP ioctl
      vt: drop access_ok() calls in unimap ioctls

 drivers/tty/vt/consolemap.c | 56 ++++++++++++++++----------------------------------------
 drivers/tty/vt/vt.c         |  6 +++---
 drivers/tty/vt/vt_ioctl.c   |  8 --------
 3 files changed, 19 insertions(+), 51 deletions(-)

-- 
⢀⣴⠾⠻⢶⣦⠀ A tit a day keeps the vet away.
⣾⠁⢰⠒⠀⣿⡁
⢿⡄⠘⠷⠚⠋⠀ (Rejoice as my small-animal-murder-machine got unbroken after
⠈⠳⣄⠀⠀⠀⠀ nearly two years of no catch!)