On Wed, Mar 04, 2020 at 12:21:51AM +0100, KP Singh wrote:
>
> > > + t = btf_type_skip_modifiers(btf, t->type, NULL);
> > > + if (!btf_type_is_int(t)) {
> >
> > Should the size of int be verified here? E.g., if some function
> > returns u8, is that ok for BPF program to return, say, (1<<30) ?
>
> Would this work?
>
> if (size != t->size) {
> bpf_log(log,
> "size accessed = %d should be %d\n",
> size, t->size);
> return false;
> }
It will cause spurious failures later when llvm optimizes
if (ret & 0xff) into u8 load.
I think btf_type_is_int() is enough as-is.
