On Tue, Jun 04, 2019 at 02:43:09PM -0700, Xing, Cedric wrote:

quoted

From: Christopherson, Sean J
Sent: Tuesday, June 04, 2019 1:37 PM

On Tue, Jun 04, 2019 at 01:29:10PM -0700, Andy Lutomirski wrote:

quoted

On Fri, May 31, 2019 at 4:32 PM Sean Christopherson
[off-list ref] wrote:

quoted

 static int sgx_encl_add_page(struct sgx_encl *encl, unsigned long
addr, diff --git a/include/linux/lsm_hooks.h
b/include/linux/lsm_hooks.h index 47f58cfb6a19..0562775424a0 100644

--- a/include/linux/lsm_hooks.h
+++ b/include/linux/lsm_hooks.h

@@ -1446,6 +1446,14 @@
  * @bpf_prog_free_security:
  *     Clean up the security information stored inside bpf prog.
  *
+ * Security hooks for Intel SGX enclaves.
+ *
+ * @enclave_load:
+ *     On success, returns 0 and optionally adjusts @allowed_prot
+ *     @vma: the source memory region of the enclave page being

loaded.

quoted

quoted

+ *     @prot: the initial protection of the enclave page.

What do you mean "initial"?  The page is always mapped PROT_NONE when
this is called, right?  I feel like I must be missing something here.

Initial protection in the EPCM.  Yet another reason to ignore SECINFO.

I know you guys are talking in the background that all pages are mmap()'ed
PROT_NONE. But that's an unnecessary limitation.

Not all pages have to be mmap()'d PROT_NONE, only pages that do not have
an associated enclave page.

And @prot here should be @target_vma->vm_flags&(VM_READ|VM_WRITE|VM_EXEC). 

I don't follow, there is no target_vma at this point.