Linux-Sgx Archive on lore.kernel.org
 help / color / Atom feed
From: Andy Lutomirski <luto@kernel.org>
To: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
Cc: Dave Hansen <dave.hansen@intel.com>,
	LKML <linux-kernel@vger.kernel.org>, X86 ML <x86@kernel.org>,
	linux-sgx@vger.kernel.org,
	Andrew Morton <akpm@linux-foundation.org>,
	"Christopherson, Sean J" <sean.j.christopherson@intel.com>,
	nhorman@redhat.com, npmccallum@redhat.com, "Ayoun,
	Serge" <serge.ayoun@intel.com>,
	"Katz-zamir, Shay" <shay.katz-zamir@intel.com>,
	"Huang, Haitao" <haitao.huang@intel.com>,
	Andy Shevchenko <andriy.shevchenko@linux.intel.com>,
	Thomas Gleixner <tglx@linutronix.de>,
	"Svahn, Kai" <kai.svahn@intel.com>,
	Borislav Petkov <bp@alien8.de>,
	Josh Triplett <josh@joshtriplett.org>,
	Andrew Lutomirski <luto@kernel.org>,
	"Huang, Kai" <kai.huang@intel.com>,
	David Rientjes <rientjes@google.com>,
	"Xing, Cedric" <cedric.xing@intel.com>
Subject: Re: [PATCH v22 00/24] Intel SGX foundations
Date: Tue, 24 Sep 2019 10:20:09 -0700
Message-ID: <CALCETrWDLX68Vi4=9Dicq9ATmJ5mv36bzrc02heNYaHaBeWumQ@mail.gmail.com> (raw)
In-Reply-To: <20190916052349.GA4556@linux.intel.com>

> On Sep 15, 2019, at 10:24 PM, Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com> wrote:
>
> On Sat, Sep 14, 2019 at 08:32:38AM -0700, Dave Hansen wrote:
>>>> On 9/14/19 6:41 AM, Jarkko Sakkinen wrote:
>>>> The proposed LSM hooks give the granularity to make yes/no decision
>>>> based on the
>>>> * The origin of the source of the source for the enclave.
>>>> * The requested permissions for the added or mapped peage.
>>>> The hooks to do these checks are provided for mmap() and EADD
>>>> operations.
>>>> With just file permissions you can still limit mmap() by having a
>>>> privileged process to build the enclaves and pass the file descriptor
>>>> to the enclave user who can mmap() the enclave within the constraints
>>>> set by the enclave pages (their permissions refine the roof that you
>>>> can mmap() any memory range within an enclave).
>> The LSM hooks are presumably fixing a problem that these patches
>> introduce.  What's that problem?
>
> I've seen the claims that one would have to degrade one's LSM policy but
> I don't think that is true.
>
> With just UNIX permissions you have probably have to restrict the access
> to /dev/sgx/enclave to control who can build enclaves. The processes who
> do not have this privilege can mmap() the enclave once they get the file
> descriptor through forking or SCM_RIGHTS.

As the person who originally raised the issue, I feel like I should
rehash the issue:

Right now, using SELinux or probably other LSMs, it's straightforward
to prevent programs from having any executable pages whose contents
doesn't come from an approved (e.g. appropriately labeled) source.
With /dev/sgx/enclave, at least as initially designed, a process that
can open /dev/sgx/enclave can execute whatever bytes they want by
sticking them into an enclave.  I fully expect that people will want
to combine these things: have unprivileged users run only
admin-approved code but *also* allow unprivileged users to run
enclaves.

> *If anything*, I would rather investigate possibility to use keyring for
> enclave signer's public keys or perhaps having extended attribute for
> the signer (SHA256) in the enclave file that could be compared during
> the EINIT.

The latter is very much like the labeled-enclave-file thing we talked about.

>
> I think either can be considered post-upstreaming.

Indeed, as long as the overall API is actually compatible with these
types of restrictions.

  reply index

Thread overview: 102+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-09-03 14:26 Jarkko Sakkinen
2019-09-03 14:26 ` [PATCH v22 01/24] x86/cpufeatures: x86/msr: Add Intel SGX hardware bits Jarkko Sakkinen
2019-09-24 15:28   ` Borislav Petkov
2019-09-24 16:11     ` Sean Christopherson
2019-09-24 16:25       ` Borislav Petkov
2019-09-03 14:26 ` [PATCH v22 02/24] x86/cpufeatures: x86/msr: Intel SGX Launch Control " Jarkko Sakkinen
2019-09-24 15:52   ` Borislav Petkov
2019-09-24 20:22     ` Sean Christopherson
2019-09-25  8:51       ` Borislav Petkov
2019-09-25 17:18         ` Sean Christopherson
2019-09-25 18:31           ` Borislav Petkov
2019-09-25 19:08             ` Sean Christopherson
2019-09-27 16:11           ` Jarkko Sakkinen
2019-09-25 14:09     ` Jarkko Sakkinen
2019-09-25 14:10       ` Jarkko Sakkinen
2019-09-25 14:38         ` Jarkko Sakkinen
2019-09-25 15:19       ` Borislav Petkov
2019-09-25 16:49         ` Sean Christopherson
2019-09-25 17:28           ` Borislav Petkov
2019-09-25 18:18             ` Sean Christopherson
2019-09-03 14:26 ` [PATCH v22 03/24] x86/mm: x86/sgx: Signal SIGSEGV with PF_SGX Jarkko Sakkinen
2019-09-24 16:04   ` Borislav Petkov
2019-09-25 14:16     ` Jarkko Sakkinen
2019-09-03 14:26 ` [PATCH v22 04/24] x86/cpu/intel: Detect SGX supprt Jarkko Sakkinen
2019-09-24 16:13   ` Borislav Petkov
2019-09-24 17:43     ` Sean Christopherson
2019-09-24 18:21       ` Borislav Petkov
2019-09-25 14:46         ` Jarkko Sakkinen
2019-09-03 14:26 ` [PATCH v22 05/24] x86/sgx: Add ENCLS architectural error codes Jarkko Sakkinen
2019-09-27 10:20   ` Borislav Petkov
2019-09-27 16:08     ` Jarkko Sakkinen
2019-09-27 17:20       ` Sean Christopherson
2019-10-01 20:23         ` Jarkko Sakkinen
2019-09-03 14:26 ` [PATCH v22 06/24] x86/sgx: Add SGX microarchitectural data structures Jarkko Sakkinen
2019-09-27 16:27   ` Borislav Petkov
2019-10-01 19:10     ` Jarkko Sakkinen
2019-10-01 20:39     ` Jarkko Sakkinen
2019-09-03 14:26 ` [PATCH v22 07/24] x86/sgx: Add wrappers for ENCLS leaf functions Jarkko Sakkinen
2019-10-04  9:45   ` Borislav Petkov
2019-10-04 18:56     ` Jarkko Sakkinen
2019-10-08  4:04     ` Sean Christopherson
2019-10-08  7:18       ` Borislav Petkov
2019-10-08 13:35         ` Sean Christopherson
2019-10-08 14:56           ` Borislav Petkov
2019-09-03 14:26 ` [PATCH v22 08/24] x86/sgx: Enumerate and track EPC sections Jarkko Sakkinen
2019-10-05  9:26   ` Borislav Petkov
2019-10-07 11:58     ` Jarkko Sakkinen
2019-09-03 14:26 ` [PATCH v22 09/24] x86/sgx: Add functions to allocate and free EPC pages Jarkko Sakkinen
2019-10-05 16:44   ` Borislav Petkov
2019-10-07 14:50     ` Sean Christopherson
2019-10-08  9:09       ` Borislav Petkov
2019-10-08 13:31         ` Sean Christopherson
2019-10-07 17:55     ` Jarkko Sakkinen
2019-10-07 18:09       ` Borislav Petkov
2019-09-03 14:26 ` [PATCH v22 10/24] x86/sgx: Add sgx_einit() for wrapping ENCLS[EINIT] Jarkko Sakkinen
2019-10-08 17:30   ` Borislav Petkov
2019-10-08 17:45     ` Sean Christopherson
2019-10-08 17:46       ` Sean Christopherson
2019-10-08 17:53         ` Borislav Petkov
2019-09-03 14:26 ` [PATCH v22 11/24] mm: Introduce vm_ops->may_mprotect() Jarkko Sakkinen
2019-10-08 17:41   ` Borislav Petkov
2019-09-03 14:26 ` [PATCH v22 12/24] x86/sgx: Linux Enclave Driver Jarkko Sakkinen
2019-10-08 17:59   ` Borislav Petkov
2019-10-08 18:17     ` Sean Christopherson
2019-10-08 19:19       ` Borislav Petkov
2019-09-03 14:26 ` [PATCH v22 13/24] x86/sgx: Add provisioning Jarkko Sakkinen
2019-09-03 14:26 ` [PATCH v22 14/24] x86/sgx: Add a page reclaimer Jarkko Sakkinen
2019-09-03 14:26 ` [PATCH v22 15/24] x86/sgx: ptrace() support for the SGX driver Jarkko Sakkinen
2019-09-03 14:26 ` [PATCH v22 16/24] x86/vdso: Add support for exception fixup in vDSO functions Jarkko Sakkinen
2019-10-02 23:18   ` Jarkko Sakkinen
2019-10-02 23:45     ` Jarkko Sakkinen
2019-10-04  0:03     ` Sean Christopherson
2019-10-04 18:49       ` Jarkko Sakkinen
2019-10-04  0:15     ` Sean Christopherson
2019-10-04 18:52       ` Jarkko Sakkinen
2019-10-05 15:54         ` Sean Christopherson
2019-10-07  7:57           ` Jarkko Sakkinen
2019-10-07  8:10             ` Jarkko Sakkinen
2019-10-07 12:04               ` Jarkko Sakkinen
2019-10-08  4:54                 ` Sean Christopherson
2019-10-05 18:39         ` Sean Christopherson
2019-10-07  8:01           ` Jarkko Sakkinen
2019-10-06 23:38         ` Jarkko Sakkinen
2019-10-06 23:40           ` Jarkko Sakkinen
2019-09-03 14:26 ` [PATCH v22 17/24] x86/fault: Add helper function to sanitize error code Jarkko Sakkinen
2019-09-03 14:26 ` [PATCH v22 18/24] x86/traps: Attempt to fixup exceptions in vDSO before signaling Jarkko Sakkinen
2019-09-03 14:26 ` [PATCH v22 19/24] x86/vdso: Add __vdso_sgx_enter_enclave() to wrap SGX enclave transitions Jarkko Sakkinen
2019-09-03 14:26 ` [PATCH v22 20/24] selftests/x86: Add a selftest for SGX Jarkko Sakkinen
2019-09-03 14:26 ` [PATCH v22 21/24] selftests/x86: Recurse into subdirectories Jarkko Sakkinen
2019-09-03 14:26 ` [PATCH v22 22/24] x86/sgx: Update MAINTAINERS Jarkko Sakkinen
2019-09-03 14:26 ` [PATCH v22 23/24] docs: x86/sgx: Document microarchitecture Jarkko Sakkinen
2019-09-27 18:15   ` Randy Dunlap
2019-09-03 14:26 ` [PATCH v22 24/24] docs: x86/sgx: Document kernel internals Jarkko Sakkinen
2019-09-27 17:07   ` Randy Dunlap
2019-10-01 19:34     ` Jarkko Sakkinen
2019-09-13 20:38 ` [PATCH v22 00/24] Intel SGX foundations Dave Hansen
2019-09-14 13:41   ` Jarkko Sakkinen
2019-09-14 15:32     ` Dave Hansen
2019-09-16  5:23       ` Jarkko Sakkinen
2019-09-24 17:20         ` Andy Lutomirski [this message]
2019-09-25 14:32           ` Jarkko Sakkinen
2019-10-02 23:42             ` Jarkko Sakkinen

Reply instructions:

You may reply publically 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='CALCETrWDLX68Vi4=9Dicq9ATmJ5mv36bzrc02heNYaHaBeWumQ@mail.gmail.com' \
    --to=luto@kernel.org \
    --cc=akpm@linux-foundation.org \
    --cc=andriy.shevchenko@linux.intel.com \
    --cc=bp@alien8.de \
    --cc=cedric.xing@intel.com \
    --cc=dave.hansen@intel.com \
    --cc=haitao.huang@intel.com \
    --cc=jarkko.sakkinen@linux.intel.com \
    --cc=josh@joshtriplett.org \
    --cc=kai.huang@intel.com \
    --cc=kai.svahn@intel.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-sgx@vger.kernel.org \
    --cc=nhorman@redhat.com \
    --cc=npmccallum@redhat.com \
    --cc=rientjes@google.com \
    --cc=sean.j.christopherson@intel.com \
    --cc=serge.ayoun@intel.com \
    --cc=shay.katz-zamir@intel.com \
    --cc=tglx@linutronix.de \
    --cc=x86@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

Linux-Sgx Archive on lore.kernel.org

Archives are clonable:
	git clone --mirror https://lore.kernel.org/linux-sgx/0 linux-sgx/git/0.git

	# If you have public-inbox 1.1+ installed, you may
	# initialize and index your mirror using the following commands:
	public-inbox-init -V2 linux-sgx linux-sgx/ https://lore.kernel.org/linux-sgx \
		linux-sgx@vger.kernel.org
	public-inbox-index linux-sgx

Example config snippet for mirrors

Newsgroup available over NNTP:
	nntp://nntp.lore.kernel.org/org.kernel.vger.linux-sgx


AGPL code for this site: git clone https://public-inbox.org/public-inbox.git