Linux-Sgx Archive on lore.kernel.org
 help / color / Atom feed
From: Sean Christopherson <sean.j.christopherson@intel.com>
To: Andy Lutomirski <luto@kernel.org>
Cc: Jordan Hand <jorhand@linux.microsoft.com>,
	Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>,
	LKML <linux-kernel@vger.kernel.org>, X86 ML <x86@kernel.org>,
	linux-sgx@vger.kernel.org,
	Andrew Morton <akpm@linux-foundation.org>,
	Dave Hansen <dave.hansen@intel.com>,
	Neil Horman <nhorman@redhat.com>,
	npmccallum@redhat.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>,
	"Huang, Kai" <kai.huang@intel.com>,
	David Rientjes <rientjes@google.com>,
	"Xing, Cedric" <cedric.xing@intel.com>,
	puiterwijk@redhat.com,
	LSM List <linux-security-module@vger.kernel.org>,
	Suresh Siddha <suresh.b.siddha@intel.com>,
	Haitao Huang <haitao.huang@linux.intel.com>
Subject: Re: [PATCH v26 10/22] x86/sgx: Linux Enclave Driver
Date: Thu, 20 Feb 2020 11:15:10 -0800
Message-ID: <20200220191510.GF3972@linux.intel.com> (raw)
In-Reply-To: <CALCETrVXnSR8fBQtqv=3zFxJCFhcHE-6XNAy3suPW+uPgFvfvg@mail.gmail.com>

On Thu, Feb 20, 2020 at 10:51:37AM -0800, Andy Lutomirski wrote:
> On Thu, Feb 20, 2020 at 10:13 AM Sean Christopherson
> <sean.j.christopherson@intel.com> wrote:
> > More than likely, the READ_IMPLIES_EXECUTE (RIE) crud rears its head
> > because part of the enclave loader is written in assembly.  Unless
> > explicitly told otherwise, the linker assumes that any program with
> > assembly code may need an executable stack, which leads to the RIE
> > personality being set for the process.  Here's a fantastic write up for
> > more details: https://www.airs.com/blog/archives/518
> >
> > There are essentially two paths we can take:
> >
> >  1) Exempt EPC pages from RIE during mmap()/mprotect(), i.e. don't add
> >     PROT_EXEC for enclaves.
> 
> Seems reasonable.
> 
> Honestly, it probably makes sense to try to exempt almost everything
> from RIE.  I'd be a bit surprised if RIE is actually useful for
> anything other than plain anonymous pages and private file mappings.

Hmm, last I looked at this I was focused on adding a generic protections
manipulator, e.g. vm_ops->mprotect_adjust() and f_op->???, and I thought
those options were too ugly to pursue.

But if we want to start killing RIE specifically, adding a boolean flag
to and f_op wouldn't be _that_ heinous, e.g.

static int do_mprotect_pkey(...)
{
	...

		/* Does the application expect PROT_READ to imply PROT_EXEC */
		if (rier && (vma->vm_flags & VM_MAYEXEC) &&
		    (!vma->vm_file || !vma->vm_file->f_op->no_read_implies_exec))
			prot |= PROT_EXEC;
}

unsigned long do_mmap(...)
{
	if ((prot & PROT_READ) && (current->personality & READ_IMPLIES_EXEC))
		if (!file || (!path_noexec(&file->f_path) &&
			      !file->f_op->no_read_implies_exec))
			prot |= PROT_EXEC;
}

  reply index

Thread overview: 55+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2020-02-09 21:25 [PATCH v26 00/22] Intel SGX foundations Jarkko Sakkinen
2020-02-09 21:25 ` [PATCH v26 01/22] x86/cpufeatures: x86/msr: Add Intel SGX hardware bits Jarkko Sakkinen
2020-02-09 21:25 ` [PATCH v26 02/22] x86/cpufeatures: x86/msr: Intel SGX Launch Control " Jarkko Sakkinen
2020-02-09 21:25 ` [PATCH v26 03/22] x86/mm: x86/sgx: Signal SIGSEGV with PF_SGX Jarkko Sakkinen
2020-02-09 21:25 ` [PATCH v26 04/22] x86/sgx: Add SGX microarchitectural data structures Jarkko Sakkinen
2020-02-09 21:25 ` [PATCH v26 05/22] x86/sgx: Add wrappers for ENCLS leaf functions Jarkko Sakkinen
2020-02-09 21:25 ` [PATCH v26 06/22] x86/cpu/intel: Detect SGX supprt Jarkko Sakkinen
2020-02-12 16:57   ` Sean Christopherson
2020-02-13 18:04     ` Jarkko Sakkinen
2020-02-09 21:25 ` [PATCH v26 07/22] x86/sgx: Enumerate and track EPC sections Jarkko Sakkinen
2020-02-09 21:25 ` [PATCH v26 08/22] x86/sgx: Add functions to allocate and free EPC pages Jarkko Sakkinen
2020-02-09 21:25 ` [PATCH v26 09/22] mm: Introduce vm_ops->may_mprotect() Jarkko Sakkinen
2020-02-09 21:25 ` [PATCH v26 10/22] x86/sgx: Linux Enclave Driver Jarkko Sakkinen
2020-02-13 13:59   ` Jethro Beekman
2020-02-13 18:07     ` Sean Christopherson
2020-02-14  9:24       ` Jethro Beekman
2020-02-14 17:11         ` Sean Christopherson
2020-02-14 17:40           ` Andy Lutomirski
2020-02-14 17:52             ` Sean Christopherson
2020-02-15 16:56               ` Andy Lutomirski
2020-02-18 22:12                 ` Sean Christopherson
2020-02-15 18:05           ` Dr. Greg
2020-02-15  7:32     ` Jarkko Sakkinen
2020-02-15  7:35       ` Jarkko Sakkinen
2020-02-19  3:26   ` Jordan Hand
2020-02-20 18:13     ` Sean Christopherson
2020-02-20 18:33       ` Jordan Hand
2020-02-20 18:48         ` Sean Christopherson
2020-02-20 22:16           ` Jarkko Sakkinen
2020-02-21  0:11             ` Jordan Hand
2020-02-21 12:53               ` Jarkko Sakkinen
2020-02-21  0:32             ` Andy Lutomirski
2020-02-21 13:01               ` Jarkko Sakkinen
2020-02-20 18:51       ` Andy Lutomirski
2020-02-20 19:15         ` Sean Christopherson [this message]
2020-02-20 22:10     ` Jarkko Sakkinen
2020-02-09 21:25 ` [PATCH v26 11/22] selftests/x86: Recurse into subdirectories Jarkko Sakkinen
2020-02-09 21:25 ` [PATCH v26 12/22] selftests/x86: Add a selftest for SGX Jarkko Sakkinen
2020-02-09 21:26 ` [PATCH v26 13/22] x86/sgx: Add provisioning Jarkko Sakkinen
2020-02-13 10:49   ` Jethro Beekman
2020-02-15  7:25     ` Jarkko Sakkinen
2020-02-09 21:26 ` [PATCH v26 14/22] x86/sgx: Add a page reclaimer Jarkko Sakkinen
2020-02-09 21:26 ` [PATCH v26 15/22] x86/sgx: ptrace() support for the SGX driver Jarkko Sakkinen
2020-02-09 21:26 ` [PATCH v26 16/22] x86/vdso: Add support for exception fixup in vDSO functions Jarkko Sakkinen
2020-02-09 21:26 ` [PATCH v26 17/22] x86/fault: Add helper function to sanitize error code Jarkko Sakkinen
2020-02-09 21:26 ` [PATCH v26 18/22] x86/traps: Attempt to fixup exceptions in vDSO before signaling Jarkko Sakkinen
2020-02-09 21:26 ` [PATCH v26 19/22] x86/vdso: Add __vdso_sgx_enter_enclave() to wrap SGX enclave transitions Jarkko Sakkinen
2020-02-13 13:29   ` Jethro Beekman
2020-02-15  7:26     ` Jarkko Sakkinen
2020-02-09 21:26 ` [PATCH v26 20/22] selftests/x86: Add vDSO selftest for SGX Jarkko Sakkinen
2020-02-09 21:26 ` [PATCH v26 21/22] x86/sgx: Update MAINTAINERS Jarkko Sakkinen
2020-02-09 21:26 ` [PATCH v26 22/22] docs: x86/sgx: Document SGX micro architecture and kernel internals Jarkko Sakkinen
2020-02-22  4:13   ` Randy Dunlap
2020-02-23 17:04     ` Jarkko Sakkinen
2020-02-23 17:05       ` Jarkko Sakkinen

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=20200220191510.GF3972@linux.intel.com \
    --to=sean.j.christopherson@intel.com \
    --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=haitao.huang@linux.intel.com \
    --cc=jarkko.sakkinen@linux.intel.com \
    --cc=jorhand@linux.microsoft.com \
    --cc=josh@joshtriplett.org \
    --cc=kai.huang@intel.com \
    --cc=kai.svahn@intel.com \
    --cc=linux-kernel@vger.kernel.org \
    --cc=linux-security-module@vger.kernel.org \
    --cc=linux-sgx@vger.kernel.org \
    --cc=luto@kernel.org \
    --cc=nhorman@redhat.com \
    --cc=npmccallum@redhat.com \
    --cc=puiterwijk@redhat.com \
    --cc=rientjes@google.com \
    --cc=suresh.b.siddha@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