On Mon, May 1, 2023 at 6:12 PM Daniel Rosenberg <drosen@xxxxxxxxxx> wrote: > > On Thu, Apr 6, 2023 at 3:13 PM Alexei Starovoitov > <alexei.starovoitov@xxxxxxxxx> wrote: > > > > +1 > > All of the DYNPTR_TYPE_FLAG_MASK flags cannot appear in type == reg->type > > here. > > They are either dynamic flags inside bpf_dynptr_kern->size > > or in arg_type. > > Like in bpf_dynptr_from_mem_proto. > > Looking at this a bit more, I believe this is to enforce packet > restrictions for DYNPTR_TYPE_SKB and DYNPTR_TYPE_XDP. When a helper > function alters a packet, dynptr slices of it are invalidated. If I > remove that annotation entirely, then the invalid_data_slice family of > tests fail. bpf_dynptr_from_mem_proto is fine since that's just local > dynptrs, which don't have any extra limitations. Ah, ok, thanks for investigating!
