linux-kernel.vger.kernel.org archive mirror
 help / color / mirror / Atom feed
From: Matthew Garrett <mjg59@google.com>
To: Kees Cook <keescook@chromium.org>
Cc: James Morris <jmorris@namei.org>,
	linux-security@vger.kernel.org,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Linux API <linux-api@vger.kernel.org>
Subject: Re: [PATCH V33 01/30] security: Support early LSMs
Date: Fri, 21 Jun 2019 12:26:51 -0700	[thread overview]
Message-ID: <CACdnJuu5SvLndNs9GBm724wLOz+QFuu3agbH4Prndt9LG=Xcbw@mail.gmail.com> (raw)
In-Reply-To: <201906202010.49D16E03@keescook>

On Thu, Jun 20, 2019 at 8:22 PM Kees Cook <keescook@chromium.org> wrote:
>
> On Thu, Jun 20, 2019 at 06:19:12PM -0700, Matthew Garrett wrote:
> > The lockdown module is intended to allow for kernels to be locked down
> > early in boot - sufficiently early that we don't have the ability to
> > kmalloc() yet. Add support for early initialisation of some LSMs, and
> > then add them to the list of names when we do full initialisation later.
>
> So, if I'm reading correctly, these "early LSMs":
>
> - start up before even boot parameter parsing has happened
> - have their position in the LSM ordering ignored
> - are initialized in boot order
> - cannot use kmalloc, as well as probably lots of other things

Accurate. I've expanded the description.

> >       pr_info("Security Framework initializing\n");
>
> I'd rather this was kept in security_init() since it's the string to
> search for when debugging normal LSM initialization.

Ok.

> >
> > @@ -343,6 +342,30 @@ int __init security_init(void)
> >            i++)
> >               INIT_HLIST_HEAD(&list[i]);
> >
> > +     for (lsm = __start_early_lsm_info; lsm < __end_early_lsm_info; lsm++) {
> > +             if (!lsm->enabled)
> > +                     lsm->enabled = &lsm_enabled_true;
> > +             initialize_lsm(lsm);
> > +     }
>
> This should call prepare_lsm() before initialize_lsm(). While not needed
> for this specific LSM, it would be nice to at least do the blog size
> calculations and keep everything the same as other LSMs.

Ok.

> > +
> > +     return 0;
> > +}
> > +
> > +/**
> > + * security_init - initializes the security framework
> > + *
> > + * This should be called early in the kernel initialization sequence.
> > + */
> > +int __init security_init(void)
> > +{
> > +     struct lsm_info *lsm;
> > +
> > +     /* Append the names of the early LSM modules now */
>
> I would clarify this comment more: "... that kmalloc() is available."

Ok,

  reply	other threads:[~2019-06-21 19:27 UTC|newest]

Thread overview: 58+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-06-21  1:19 [PATCH V33 00/30] Lockdown as an LSM Matthew Garrett
2019-06-21  1:19 ` [PATCH V33 01/30] security: Support early LSMs Matthew Garrett
2019-06-21  3:21   ` Kees Cook
2019-06-21 19:26     ` Matthew Garrett [this message]
2019-06-21  5:23   ` Andy Lutomirski
2019-06-21 19:27     ` Matthew Garrett
2019-06-21  1:19 ` [PATCH V33 02/30] security: Add a "locked down" LSM hook Matthew Garrett
2019-06-21  3:23   ` Kees Cook
2019-06-21 19:29     ` Matthew Garrett
2019-06-21  1:19 ` [PATCH V33 03/30] security: Add a static lockdown policy LSM Matthew Garrett
2019-06-21  3:44   ` Kees Cook
2019-06-21 19:37     ` Matthew Garrett
2019-06-21 21:04       ` Matthew Garrett
2019-06-21 22:31   ` Mimi Zohar
2019-06-21  1:19 ` [PATCH V33 04/30] Enforce module signatures if the kernel is locked down Matthew Garrett
2019-06-21  3:46   ` Kees Cook
2019-06-21  1:19 ` [PATCH V33 05/30] Restrict /dev/{mem,kmem,port} when " Matthew Garrett
2019-06-21  1:19 ` [PATCH V33 06/30] kexec_load: Disable at runtime if " Matthew Garrett
2019-06-21  1:19 ` [PATCH V33 07/30] Copy secure_boot flag in boot params across kexec reboot Matthew Garrett
2019-06-21  1:19 ` [PATCH V33 08/30] kexec_file: split KEXEC_VERIFY_SIG into KEXEC_SIG and KEXEC_SIG_FORCE Matthew Garrett
2019-06-21  1:19 ` [PATCH V33 09/30] kexec_file: Restrict at runtime if the kernel is locked down Matthew Garrett
2019-06-21  1:19 ` [PATCH V33 10/30] hibernate: Disable when " Matthew Garrett
2019-06-21  1:19 ` [PATCH V33 11/30] uswsusp: " Matthew Garrett
2019-06-21  1:19 ` [PATCH V33 12/30] PCI: Lock down BAR access " Matthew Garrett
2019-06-21  1:19 ` [PATCH V33 13/30] x86: Lock down IO port " Matthew Garrett
2019-06-21  1:19 ` [PATCH V33 14/30] x86/msr: Restrict MSR " Matthew Garrett
2019-06-21  1:19 ` [PATCH V33 15/30] ACPI: Limit access to custom_method " Matthew Garrett
2019-06-21  1:19 ` [PATCH V33 16/30] acpi: Ignore acpi_rsdp kernel param when the kernel has been " Matthew Garrett
2019-06-21  1:19 ` [PATCH V33 17/30] acpi: Disable ACPI table override if the kernel is " Matthew Garrett
2019-06-21  1:19 ` [PATCH V33 18/30] Prohibit PCMCIA CIS storage when " Matthew Garrett
2019-06-21  1:19 ` [PATCH V33 19/30] Lock down TIOCSSERIAL Matthew Garrett
2019-06-21  1:19 ` [PATCH V33 20/30] Lock down module params that specify hardware parameters (eg. ioport) Matthew Garrett
2019-06-21  1:19 ` [PATCH V33 21/30] x86/mmiotrace: Lock down the testmmiotrace module Matthew Garrett
2019-06-26 12:46   ` Steven Rostedt
2019-06-21  1:19 ` [PATCH V33 22/30] Lock down /proc/kcore Matthew Garrett
2019-06-21  1:19 ` [PATCH V33 23/30] Lock down tracing and perf kprobes when in confidentiality mode Matthew Garrett
2019-06-21  1:19 ` [PATCH V33 24/30] bpf: Restrict bpf when kernel lockdown is " Matthew Garrett
2019-06-21  5:22   ` Andy Lutomirski
2019-06-21 20:05     ` Matthew Garrett
2019-06-26 20:22     ` James Morris
2019-06-27  0:57       ` Andy Lutomirski
2019-06-27 14:35         ` Stephen Smalley
2019-06-27 18:06           ` James Morris
2019-06-27 20:16             ` Stephen Smalley
2019-06-27 23:16               ` Matthew Garrett
2019-06-27 23:23                 ` Andy Lutomirski
2019-06-27 23:27           ` Andy Lutomirski
2019-06-28 18:47             ` Matthew Garrett
2019-06-29 23:47               ` Andy Lutomirski
2019-06-21  1:19 ` [PATCH V33 25/30] Lock down perf when " Matthew Garrett
2019-06-21  1:19 ` [PATCH V33 26/30] kexec: Allow kexec_file() with appropriate IMA policy when locked down Matthew Garrett
2019-06-21  1:19 ` [PATCH V33 27/30] lockdown: Print current->comm in restriction messages Matthew Garrett
2019-06-21  4:09   ` Kees Cook
2019-06-21  1:19 ` [PATCH V33 28/30] debugfs: Restrict debugfs when the kernel is locked down Matthew Garrett
2019-06-21  1:19 ` [PATCH V33 29/30] tracefs: Restrict tracefs " Matthew Garrett
2019-06-26 13:07   ` Steven Rostedt
2019-06-26 19:39     ` Matthew Garrett
2019-06-21  1:19 ` [PATCH V33 30/30] efi: Restrict efivar_ssdt_load " Matthew Garrett

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='CACdnJuu5SvLndNs9GBm724wLOz+QFuu3agbH4Prndt9LG=Xcbw@mail.gmail.com' \
    --to=mjg59@google.com \
    --cc=jmorris@namei.org \
    --cc=keescook@chromium.org \
    --cc=linux-api@vger.kernel.org \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-security@vger.kernel.org \
    /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).