Re: [PATCH v7 bpf-next 06/12] bpf, x86: add support for indirect jumps

[Anton Protopopov <a.s.protopopov@gmail.com>]

On 25/10/26 07:27PM, Anton Protopopov wrote:
> Add support for a new instruction
>
> [...]
>
> @@ -17823,6 +17851,197 @@ static struct bpf_iarray *iarray_realloc(struct bpf_iarray *old, size_t n_elem)
>  	return new;
>  }
>  
> +static int copy_insn_array(struct bpf_map *map, u32 start, u32 end, u32 *items)
> +{
> +	struct bpf_insn_array_value *value;
> +	u32 i;
> +
> +	for (i = start; i <= end; i++) {
> +		value = map->ops->map_lookup_elem(map, &i);
> +		if (!value)
> +			return -EINVAL;
> +		items[i - start] = value->xlated_off;
> +	}
> +	return 0;
> +}

AI said that the function here can copy a INSN_DELETED as xlated
offset. This doesn't look correct. This function is executed in
check_cfg first, then in check_indirect_jump. And the INSN_DELETED
may only be introduced after the verification is done in the "remove
dead code" or "remove nops".

> [...]