Re: [PATCH RFC] x86/sgx: Check that the address is within ELRANGE

[Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>]

On Mon, 2019-06-17 at 15:30 -0700, Sean Christopherson wrote:
> On Thu, Jun 13, 2019 at 07:42:40PM +0300, Jarkko Sakkinen wrote:
> > In sgx_encl_page_alloc() check that the given address within the
> > ELRANGE. Return -EINVAL if not.
> > 
> > Reported-by: Shay Katz-zamir <shay.katz-zamir@intel.com>
> > Cc: Sean Christopherson <sean.j.christopherson@intel.com>
> > Signed-off-by: Jarkko Sakkinen <jarkko.sakkinen@linux.intel.com>
> > ---
> >  arch/x86/kernel/cpu/sgx/driver/ioctl.c | 7 +++++++
> >  1 file changed, 7 insertions(+)
> > 
> > diff --git a/arch/x86/kernel/cpu/sgx/driver/ioctl.c
> > b/arch/x86/kernel/cpu/sgx/driver/ioctl.c
> > index d17c60dca114..9d3fc770b4d9 100644
> > --- a/arch/x86/kernel/cpu/sgx/driver/ioctl.c
> > +++ b/arch/x86/kernel/cpu/sgx/driver/ioctl.c
> > @@ -240,19 +240,26 @@ static struct sgx_encl_page
> > *sgx_encl_page_alloc(struct sgx_encl *encl,
> >  	struct sgx_encl_page *encl_page;
> >  	int ret;
> >  
> > +	if (addr < encl->base || addr > (encl->base + encl->size))
> 
> The upper bounds check should be "addr >= (encl->base + encl->size)" or
> "addr > (encl->base + encl->size - 1)"

Right, thanks :-) Shay told me that this did not happen with earlier
patch set versions but I could not spot why. Have to look again
before merging.

/Jarkko