On Thu, May 30, 2019 at 12:20:45PM -0700, Andy Lutomirski wrote: > On Thu, May 30, 2019 at 11:01 AM Sean Christopherson > <sean.j.christopherson@xxxxxxxxx> wrote: > > > > On Thu, May 30, 2019 at 09:14:10AM -0700, Andy Lutomirski wrote: > > > Enclave file -- that is, the file backing the vma from which the data is loaded. > > > > It wasn't explicitly called out in Andy's proposal(s), but the idea is > > that the SGX driver would effectively inherit permissions from the source > > VMA (EADD needs a source for the initial value of the encave page). > > I actually meant for it to *not* work like this. I don't want the > source VMA to have to be VM_EXEC. I think the LSM should just check > permissions on ->vm_file. But if ->vm_file is NULL, i.e. the enclave is not backed by a file, then PROCESS__EXECMEM is required (or more likely, ENCLAVE__EXECMEM). In practice, it's the same net effect of using sigstruct as a proxy, i.e. *something* has to get to the file system to avoid EXECMEM. But putting the entire enclave to the filesystem seems like a heaver lift than dumping the sigstruct. And if sigstruct needs to be in the file system for security_enclave_create/init()...
