On Thu, Dec 05, 2019 at 05:28:42PM +0300, Dan Carpenter wrote:
> On Thu, Dec 05, 2019 at 04:27:03PM +0300, Dan Carpenter wrote:
> > > We hardcode symbols of interest that we consider to be untagged addresses. This
> > > provides good coverage but isn't very flexible. A better approach would be to
> > > annotate the kernel with address space tags, such as is the case for __user,
> > > __percpu, etc. Thus variables, struct members and function parameters could be
> > > annotated to indicate that they contain untagged addresses. Unfortunately:
> > >
> > > - At present it's not possible to determine a struct member's address space
> > > from Smatch
> >
> > I'm not sure how to get the address space for anything not just struct
> > members. :( I will investigate.
>
> I was using the wrong attribute in my testing. In the kernel __user is
>
> #define __user __attribute__((noderef, address_space(1)))
>
> Just get_type() should work:
>
> arg = get_argument_from_call_expr(expr->args, 0);
> if (!arg)
> return;
> type = get_type(arg);
> if (!type || !type->ctype.as)
> return;
> sm_msg("%s: expr = '%s' address space = %s", __func__, expr_to_str(expr), type->ctype.as->name);
Ideally, this should use show_as() to display the address space.
-- Luc
