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>>>           return 0; >>> +    case PTR_TO_MAP_KEY: >>> +        if (mask_to_left) { >>> +            *ptr_limit = ptr_reg->umax_value + ptr_reg->off; >>> +        } else { >>> +            off = ptr_reg->smin_value + ptr_reg->off; >>> +            *ptr_limit = ptr_reg->map_ptr->key_size - off; >>> +        } >>> +        return 0; >> >> This part cannot be exercised because for_each will require cap_bpf. >> Eventually we might relax this requirement and above code will be >> necessary. >> Could you manually test it that it's working as expected by forcing >> sanitize_ptr_alu() to act on it? > > I did some manual test and hacking the verifier to make this code > executed and it looks fine and verifier succeeded. > > But since this code won't execute with current implementation > with bpf_capable(). It probably makes sense to remove this code > for now and will add it back later once bpf_pseudo_func is permitted for > unprivileged user. I think we might forget it later. I would leave the code here and maybe add the comment that it's tested for future use, but not needed yet.