From: Linus Torvalds <torvalds@linux-foundation.org>
To: Kees Cook <keescook@chromium.org>
Cc: Andy Lutomirski <luto@amacapital.net>,
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>,
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 <kernel-team@fb.com>,
Linux API <linux-api@vger.kernel.org>
Subject: Re: [PATCH net-next] modules: allow modprobe load regular elf binaries
Date: Thu, 8 Mar 2018 19:17:39 -0800 [thread overview]
Message-ID: <CA+55aFy9OoeWpHnLGCiLWxPz8tyzPaK4HS-4OfH6KEhNmsQzDQ@mail.gmail.com> (raw)
In-Reply-To: <CA+55aFwRGDPvaCUgMtqnQHb2PZ77JSMQMQVf1znSN+PiV7NR-Q@mail.gmail.com>
On Thu, Mar 8, 2018 at 7:06 PM, Linus Torvalds
<torvalds@linux-foundation.org> wrote:
>
> So I don't like Andy's "let's make it a kernel module and then that
> kernel module can execve() a blob". THAT seems like just stupid
> indirection.
>
> But I do like Andy's "execve a blob" part, because it is the *blob*
> that has had its signature verified, not the file!
To be honest., Andy's approach has the advantage that all the
synchronization we do for modules still works.
In particular, we have module loading logic where we synchronize
loading of modules with the same name, so that two things that do
request_module() concurrently will not lead to two modules being
loaded.
See that whole "module_mutex" thing, and the logic in (for example)
"add_unformed_module()".
Andrei's patch short-circuits the module loading before that, so if
you have two concurrent request_module() calls, you'll end up with no
serialization, and two executables.
So maybe Andy is right. He often is, after all.
Linus
next prev parent reply other threads:[~2018-03-09 3:17 UTC|newest]
Thread overview: 75+ 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 1:34 ` Alexei Starovoitov
2018-03-06 2:13 ` Randy Dunlap
2018-03-06 3:02 ` Alexei Starovoitov
2018-03-06 3:02 ` Alexei Starovoitov
2018-03-06 11:05 ` Greg KH
2018-03-07 1:07 ` Alexei Starovoitov
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
2018-03-08 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 0:57 ` Alexei Starovoitov
2018-03-09 1:04 ` Andy Lutomirski
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 [this message]
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 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
2018-03-22 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=CA+55aFy9OoeWpHnLGCiLWxPz8tyzPaK4HS-4OfH6KEhNmsQzDQ@mail.gmail.com \
--to=torvalds@linux-foundation.org \
--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=luto@amacapital.net \
--cc=mcgrof@kernel.org \
--cc=netdev@vger.kernel.org \
--cc=tixxdz@gmail.com \
--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 an external index of several public inboxes,
see mirroring instructions on how to clone and mirror
all data and code used by this external index.