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@xxxxxxxxxxxxxxx> 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@xxxxxxxxx> > > > > 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. Agreed. I've already (somewhat unknowingly) reworked the SELinux patch such that it ignores @prot (the SECINFO protections) and only looks at @allowed_prot (the declared protections). If the kernel ignores SECINFO protections entirely then the LSM hook can simply be: int selinux_enclave_load(struct vm_area_struct *vma, unsigned long prot) I.e. LSMs can be blissfully unaware that @prot isn't technically what's going into the PTEs *now*.
