On Sun, Mar 20, 2022 at 09:25:00PM +0530, Kumar Kartikeya Dwivedi wrote:
> @@ -820,9 +904,31 @@ static int map_check_btf(struct bpf_map *map, const struct btf *btf,
> return -EOPNOTSUPP;
> }
>
> - if (map->ops->map_check_btf)
> + map->kptr_off_tab = btf_find_kptr(btf, value_type);
> + if (map_value_has_kptr(map)) {
> + if (!bpf_capable())
> + return -EPERM;
Not sure if this has been brought up.
No need to bpf_map_free_kptr_off_tab() in the case?
> + if (map->map_flags & BPF_F_RDONLY_PROG) {
> + ret = -EACCES;
> + goto free_map_tab;
> + }
> + if (map->map_type != BPF_MAP_TYPE_HASH &&
> + map->map_type != BPF_MAP_TYPE_LRU_HASH &&
> + map->map_type != BPF_MAP_TYPE_ARRAY) {
> + ret = -EOPNOTSUPP;
> + goto free_map_tab;
> + }
> + }
If btf_find_kptr() returns err, it can be ignored and continue ?
btw, it is quite unusual to store an err ptr in map.
How about only stores NULL or a valid ptr in map->kptr_off_tab?
> +
> + if (map->ops->map_check_btf) {
> ret = map->ops->map_check_btf(map, btf, key_type, value_type);
> + if (ret < 0)
> + goto free_map_tab;
> + }
>
> + return ret;
> +free_map_tab:
> + bpf_map_free_kptr_off_tab(map);
> return ret;
> }
