linux-api.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Andy Lutomirski <luto@amacapital.net>
To: Alexei Starovoitov <ast@fb.com>
Cc: Kees Cook <keescook@chromium.org>,
	Alexei Starovoitov <ast@kernel.org>,
	Djalal Harouni <tixxdz@gmail.com>,
	Al Viro <viro@zeniv.linux.org.uk>,
	"David S. Miller" <davem@davemloft.net>,
	Daniel Borkmann <daniel@iogearbox.net>,
	Linus Torvalds <torvalds@linux-foundation.org>,
	Greg KH <gregkh@linuxfoundation.org>,
	"Luis R. Rodriguez" <mcgrof@kernel.org>,
	Network Development <netdev@vger.kernel.org>,
	LKML <linux-kernel@vger.kernel.org>,
	kernel-team@fb.com, Linux API <linux-api@vger.kernel.org>
Subject: Re: [PATCH net-next] modules: allow modprobe load regular elf binaries
Date: Fri, 9 Mar 2018 01:04:39 +0000	[thread overview]
Message-ID: <CALCETrVUOToH5WnZMdpk+Vt=NK5OuE=ha62sj7cN5Hw5=qrgRw@mail.gmail.com> (raw)
In-Reply-To: <357c330f-0165-b7a4-7ecc-4cd797e61e15@fb.com>

On Fri, Mar 9, 2018 at 12:57 AM, Alexei Starovoitov <ast@fb.com> wrote:
> On 3/8/18 4:24 PM, Kees Cook wrote:
>>
>> As Andy asked earlier, why not DYN too to catch PIE executables? Seems
>> like forcing the userspace helper to be non-PIE would defeat some of
>> the userspace defenses in use in most distros.
>
>
> because we don't add features without concrete users.

I disagree here.  If you're going to add a magic trick that triggers
an execve(), then I think you should either support *both* standard,
widely-used types of ELF programs or you should give a compelling use
case that works for ET_EXEC but not for ET_DYN.  Keep in mind that
many distros have a very strong preference for ET_DYN.

Or you could argue that ET_DYN requires tooling changes, but I think
it's awkward to ask the tooling to change in advance of the kernel
being willing to actually invoke the thing.  I'm not actually
convinced that any tooling changes would be needed, though.

  reply	other threads:[~2018-03-09  1:04 UTC|newest]

Thread overview: 68+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2018-03-06  1:34 [PATCH net-next] modules: allow modprobe load regular elf binaries Alexei Starovoitov
2018-03-06  2:13 ` Randy Dunlap
2018-03-06  3:02   ` Alexei Starovoitov
2018-03-06 11:05 ` Greg KH
2018-03-07  1:07   ` Alexei Starovoitov
2018-03-07  3:24     ` Greg KH
2018-03-06 19:12 ` Linus Torvalds
2018-03-06 23:42   ` Chris Mason
2018-05-02  9:12     ` Jesper Dangaard Brouer
2018-03-06 20:01 ` Andy Lutomirski
2018-03-06 20:26   ` Linus Torvalds
2018-03-07 17:22 ` David Miller
2018-03-08  1:23 ` Luis R. Rodriguez
2018-03-08 23:07   ` Alexei Starovoitov
2018-03-09  1:58     ` Luis R. Rodriguez
2018-03-09  0:24 ` Kees Cook
2018-03-09  0:57   ` Alexei Starovoitov
2018-03-09  1:04     ` Andy Lutomirski [this message]
2018-03-09  1:25       ` Alexei Starovoitov
2018-03-09  1:24     ` Kees Cook
2018-03-09  0:59   ` Andy Lutomirski
2018-03-09  1:20     ` Alexei Starovoitov
2018-03-09  2:12       ` Andy Lutomirski
2018-03-09  2:31         ` David Miller
2018-03-09  3:10           ` Andy Lutomirski
2018-03-09  3:27         ` Alexei Starovoitov
2018-03-09  1:38     ` Linus Torvalds
2018-03-09  1:44       ` Kees Cook
2018-03-09  3:06         ` Linus Torvalds
2018-03-09  3:17           ` Linus Torvalds
2018-03-09  3:54           ` Andy Lutomirski
2018-03-09  5:08             ` Alexei Starovoitov
2018-03-09 15:16               ` Andy Lutomirski
2018-03-09 15:39                 ` Alexei Starovoitov
2018-03-09 16:24                   ` Andy Lutomirski
2018-03-09 17:32                     ` Alexei Starovoitov
2018-03-09 18:15                       ` Greg KH
2018-03-09 18:23                         ` Andy Lutomirski
2018-03-09 18:29                           ` Greg KH
2018-03-09 18:50                           ` Alexei Starovoitov
2018-03-09 18:55                             ` David Miller
2018-03-09 19:37                               ` Andy Lutomirski
2018-03-10  1:43                                 ` Alexei Starovoitov
2018-03-11  2:17                                   ` Andy Lutomirski
2018-03-09 18:17               ` Linus Torvalds
2018-03-09 18:35                 ` David Miller
2018-03-09 18:43                   ` Kees Cook
2018-03-09 18:50                     ` Linus Torvalds
2018-03-09 18:54                       ` Kees Cook
2018-03-09 18:58                       ` Alexei Starovoitov
2018-03-12 12:02                         ` Edward Cree
2018-03-12 17:49                           ` Alexei Starovoitov
2018-03-09 18:48                 ` Andy Lutomirski
2018-03-09 18:53                   ` Linus Torvalds
2018-03-09 18:57                     ` David Miller
2018-03-09 19:12                       ` Linus Torvalds
2018-03-09 19:38                         ` Linus Torvalds
2018-03-09 19:45                           ` Andy Lutomirski
2018-03-10  2:34                           ` Alexei Starovoitov
2018-03-10 14:08                             ` Luis R. Rodriguez
2018-03-10 15:16                               ` Luis R. Rodriguez
2018-03-10 15:34                                 ` Luis R. Rodriguez
2018-03-12 17:22                                   ` Alexei Starovoitov
2018-03-13  8:48                                     ` Greg Kroah-Hartman
2018-03-22 20:54                                 ` Luis R. Rodriguez
2018-03-22 22:15                                   ` Andy Lutomirski
2018-03-22 22:21                                     ` Alexei Starovoitov
2018-03-23  2:47                                     ` Luis R. Rodriguez

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to='CALCETrVUOToH5WnZMdpk+Vt=NK5OuE=ha62sj7cN5Hw5=qrgRw@mail.gmail.com' \
    --to=luto@amacapital.net \
    --cc=ast@fb.com \
    --cc=ast@kernel.org \
    --cc=daniel@iogearbox.net \
    --cc=davem@davemloft.net \
    --cc=gregkh@linuxfoundation.org \
    --cc=keescook@chromium.org \
    --cc=kernel-team@fb.com \
    --cc=linux-api@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=mcgrof@kernel.org \
    --cc=netdev@vger.kernel.org \
    --cc=tixxdz@gmail.com \
    --cc=torvalds@linux-foundation.org \
    --cc=viro@zeniv.linux.org.uk \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html

* If your mail client supports setting the In-Reply-To header
  via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).