[RFC PATCH 7/9] x86/sgx: Enforce noexec filesystem restriction for enclaves

[Jarkko Sakkinen]

On Tue, Jun 04, 2019 at 01:25:10PM -0700, Andy Lutomirski wrote:
> On Tue, Jun 4, 2019 at 9:26 AM Jarkko Sakkinen
> <jarkko.sakkinen at linux.intel.com> wrote:
> >
> > On Fri, May 31, 2019 at 04:31:57PM -0700, Sean Christopherson wrote:
> > > Do not allow an enclave page to be mapped with PROT_EXEC if the source
> > > page is backed by a file on a noexec file system.
> > >
> > > Signed-off-by: Sean Christopherson <sean.j.christopherson at intel.com>
> >
> > Why don't you just check in sgx_encl_add_page() that whether the path
> > comes from noexec and deny if SECINFO contains X?
> >
> 
> SECINFO seems almost entirely useless for this kind of thing because
> of SGX2.  I'm thinking that SECINFO should be completely ignored for
> anything other than its required architectural purpose.

Not exactly sure why using it to pass the RWX bits to EADD ioctl would
cause anything to SGX2 support.

/Jarkko