On Wed, 15 Feb 2023 02:51:23 -0600, Huang, Kai <kai.huang@xxxxxxxxx> wrote:
> > >
>
> Since sgx_mmap() can happen before enclave is created, calculating the
> vm_pgoff
> from enclave_base is conceptually wrong. Even if you really want to
do
> it, it
> should be:
>
> if (enclave_has_initialized())
> vma->vm_pgoff = ...;
I got your point now. I can add a condition to test the SGX_ENCL_CREATED
bit. However, we still have a hole if we must handle the sequence
mmap(..., enclave_fd) being called before ECREATE ioctl. We can't leave
vm_pgoff not set for those cases.
Since no one does that so far, can we explicitly return an error from
sgx_mmap when that happens?
Other suggestions?
As I replied to patch 4/4, I believe userspace should pass the correct
pgoff in
mmap(). It's wrong to always pass 0 or any random value.
If userspace follow the mmap() rule, you won't need to manually set
vm_pgoff
here (which is hacky IMHO). Everything works fine.
SGX driver was following MAP_ANONYMOUS semantics. If we change that, it'd
break current usage/ABI.
I still think returning error for cases mmap(..., enclave_fd) if enclave
is not created would be less intrusive change.
Haitao
