linux-security-module.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Kees Cook <keescook@chromium.org>
To: "Serge E. Hallyn" <serge@hallyn.com>
Cc: Paul Moore <paul@paul-moore.com>,
	James Morris <jmorris@namei.org>,
	linux-security-module@vger.kernel.org,
	Mimi Zohar <zohar@linux.ibm.com>,
	Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	linux-kernel@vger.kernel.org, linux-hardening@vger.kernel.org
Subject: Re: [PATCH] LoadPin: Ignore the "contents" argument of the LSM hooks
Date: Tue, 13 Dec 2022 20:06:55 -0800	[thread overview]
Message-ID: <202212132006.F29BB81A@keescook> (raw)
In-Reply-To: <20221212211319.GA15511@mail.hallyn.com>

On Mon, Dec 12, 2022 at 03:13:19PM -0600, Serge E. Hallyn wrote:
> On Fri, Dec 09, 2022 at 11:54:57AM -0800, Kees Cook wrote:
> > LoadPin only enforces the read-only origin of kernel file reads. Whether
> > or not it was a partial read isn't important. Remove the overly
> > conservative checks so that things like partial firmware reads will
> > succeed (i.e. reading a firmware header).
> > 
> > Fixes: 2039bda1fa8d ("LSM: Add "contents" flag to kernel_read_file hook")
> > Cc: Paul Moore <paul@paul-moore.com>
> > Cc: James Morris <jmorris@namei.org>
> > Cc: "Serge E. Hallyn" <serge@hallyn.com>
> 
> Acked-by: Serge Hallyn <serge@hallyn.com>
> 
> Seems reasonable.

Thanks!

> So the patch which introduced this was
> 2039bda1f: LSM: Add "contents" flag to kernel_read_file hook
> It sounds like the usage of @contents which it added to ima still
> makes sense.  But what about the selinux_kernel_read_file() one?

I think those continue to make sense since those LSM may be sensitive to
the _content_ (rather than the _origin_) of the file.

-Kees

-- 
Kees Cook

  reply	other threads:[~2022-12-14  4:07 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-12-09 19:54 [PATCH] LoadPin: Ignore the "contents" argument of the LSM hooks Kees Cook
2022-12-12 21:13 ` Serge E. Hallyn
2022-12-14  4:06   ` Kees Cook [this message]
2022-12-15 20:16     ` Paul Moore
2022-12-14  4:06 ` 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=202212132006.F29BB81A@keescook \
    --to=keescook@chromium.org \
    --cc=gregkh@linuxfoundation.org \
    --cc=jmorris@namei.org \
    --cc=linux-hardening@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-security-module@vger.kernel.org \
    --cc=paul@paul-moore.com \
    --cc=serge@hallyn.com \
    --cc=zohar@linux.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;
as well as URLs for NNTP newsgroup(s).