From: Rusty Russell <rusty@rustcorp.com.au>
To: "H. Peter Anvin" <hpa@zytor.com>, mtk.manpages@gmail.com
Cc: Kees Cook <keescook@chromium.org>,
linux-kernel@vger.kernel.org,
Andrew Morton <akpm@linux-foundation.org>,
Mimi Zohar <zohar@linux.vnet.ibm.com>,
Serge Hallyn <serge.hallyn@canonical.com>,
Arnd Bergmann <arnd@arndb.de>,
James Morris <james.l.morris@oracle.com>,
Al Viro <viro@zeniv.linux.org.uk>, Eric Paris <eparis@redhat.com>,
Jiri Kosina <jkosina@suse.cz>,
linux-security-module@vger.kernel.org
Subject: Re: [PATCH 1/4] module: add syscall to load module from fd
Date: Fri, 19 Oct 2012 12:53:14 +1030 [thread overview]
Message-ID: <87a9vjp5d9.fsf@rustcorp.com.au> (raw)
In-Reply-To: <508011AD.5080307@zytor.com>
"H. Peter Anvin" <hpa@zytor.com> writes:
> Given that, I have to say I now seriously question the value of
> finit_module(). The kernel can trivially discover if the pointed-to
> memory area is a MAP_SHARED mmap() of a file descriptor and if so which
> file descriptor... why can't we handle this behind the scenes?
It is a bit more indirect, but also in practice it's a bit trickier than
that. We need to ensure the memory doesn't change underneath us and
stays attached to that fd. I can easily see that code slipping and
ending in an exploit.
But that may be my irrational fear of the mm :)
Cheers,
Rusty.
next prev parent reply other threads:[~2012-10-19 2:28 UTC|newest]
Thread overview: 56+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-09-20 22:14 Kees Cook
2012-09-20 22:14 ` [PATCH 2/4] security: introduce kernel_module_from_file hook Kees Cook
2012-09-21 12:42 ` Mimi Zohar
2012-09-20 22:14 ` [PATCH 3/4] ARM: add finit_module syscall to ARM Kees Cook
2012-09-21 13:15 ` Arnd Bergmann
2012-09-21 14:59 ` Russell King
2012-09-21 15:43 ` Kees Cook
2012-09-20 22:15 ` [PATCH 4/4] add finit_module syscall to asm-generic Kees Cook
2012-09-21 2:22 ` [PATCH 1/4] module: add syscall to load module from fd James Morris
2012-09-21 3:07 ` Kees Cook
2012-09-21 3:09 ` Mimi Zohar
2012-09-21 17:56 ` John Johansen
2012-10-03 22:40 ` Kees Cook
2012-10-04 5:39 ` Rusty Russell
2012-10-04 12:50 ` Mimi Zohar
2012-10-05 3:50 ` Rusty Russell
2012-10-05 7:12 ` Kees Cook
2012-10-04 20:28 ` Kees Cook
2012-10-09 21:54 ` Michael Kerrisk
2012-10-09 21:58 ` H. Peter Anvin
2012-10-09 22:03 ` Michael Kerrisk (man-pages)
2012-10-09 22:09 ` H. Peter Anvin
[not found] ` <CAKgNAkjfkbYOQocuGRAKU=0P2CQCvmedhRMJZPnkUMnnxSOsqg@mail.gmail.com>
2012-10-10 5:54 ` Michael Kerrisk (man-pages)
2012-10-11 22:16 ` Rusty Russell
2012-10-12 5:16 ` Michael Kerrisk (man-pages)
2012-10-18 3:12 ` Rusty Russell
2012-10-18 5:39 ` Lucas De Marchi
2012-10-18 12:59 ` Michael Kerrisk (man-pages)
2012-10-22 7:39 ` Rusty Russell
2012-10-23 2:37 ` Lucas De Marchi
2012-10-23 3:40 ` Kees Cook
2012-10-23 4:08 ` Lucas De Marchi
2012-10-23 15:42 ` Kees Cook
2012-10-23 15:45 ` H. Peter Anvin
2012-10-23 16:25 ` Lucas De Marchi
2012-10-24 3:06 ` Rusty Russell
2012-10-23 7:38 ` Michael Kerrisk (man-pages)
2012-10-30 21:57 ` Kees Cook
2012-11-01 1:03 ` Rusty Russell
2012-12-21 0:01 ` Michael Kerrisk
2013-01-03 0:12 ` Rusty Russell
2013-01-06 18:59 ` Michael Kerrisk (man-pages)
2013-01-06 20:24 ` Kees Cook
2013-01-07 1:41 ` Michael Kerrisk (man-pages)
2013-01-09 17:29 ` Lucas De Marchi
2013-01-10 0:55 ` Michael Kerrisk (man-pages)
2012-10-18 4:24 ` H. Peter Anvin
2012-10-18 8:05 ` Michael Kerrisk (man-pages)
2012-10-18 14:26 ` H. Peter Anvin
2012-10-18 15:28 ` Kees Cook
2012-10-18 15:30 ` H. Peter Anvin
2012-10-19 2:23 ` Rusty Russell [this message]
2012-10-19 2:54 ` H. Peter Anvin
2012-10-19 10:46 ` Alon Ziv
2012-10-20 4:05 ` Rusty Russell
2012-10-04 20:22 [PATCH v5] " Kees Cook
2012-10-04 20:22 ` [PATCH 1/4] " Kees Cook
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=87a9vjp5d9.fsf@rustcorp.com.au \
--to=rusty@rustcorp.com.au \
--cc=akpm@linux-foundation.org \
--cc=arnd@arndb.de \
--cc=eparis@redhat.com \
--cc=hpa@zytor.com \
--cc=james.l.morris@oracle.com \
--cc=jkosina@suse.cz \
--cc=keescook@chromium.org \
--cc=linux-kernel@vger.kernel.org \
--cc=linux-security-module@vger.kernel.org \
--cc=mtk.manpages@gmail.com \
--cc=serge.hallyn@canonical.com \
--cc=viro@zeniv.linux.org.uk \
--cc=zohar@linux.vnet.ibm.com \
/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
Powered by JetHome