Re: [bpf-next v1 8/9] bpf: Provide helper to do lookups in kernel FIB table

[David Ahern <dsahern@gmail.com>]

On 5/3/18 6:45 PM, Daniel Borkmann wrote:
>> +	.ret_type	= RET_INTEGER,
>> +	.arg1_type      = ARG_PTR_TO_CTX,
>> +	.arg2_type      = ARG_PTR_TO_MEM,
>> +	.arg3_type      = ARG_CONST_SIZE,
>> +	.arg4_type	= ARG_ANYTHING,
>> +};
>> +
>> +BPF_CALL_4(bpf_skb_fib_lookup, struct sk_buff *, skb,
>> +	   struct bpf_fib_lookup *, params, int, plen, u32, flags)
>> +{
>> +	if (plen < sizeof(*params))
>> +		return -EINVAL;
>> +
>> +	switch (params->family) {
>> +#if IS_ENABLED(CONFIG_INET)
>> +	case AF_INET:
>> +		return bpf_ipv4_fib_lookup(dev_net(skb->dev), params, flags);
>> +#endif
>> +#if IS_ENABLED(CONFIG_IPV6)
>> +	case AF_INET6:
>> +		return bpf_ipv6_fib_lookup(dev_net(skb->dev), params, flags);
>> +#endif
>> +	}
>> +	return -ENOTSUPP;
>> +}
>> +
>> +static const struct bpf_func_proto bpf_skb_fib_lookup_proto = {
>> +	.func		= bpf_skb_fib_lookup,
>> +	.gpl_only	= true,
>> +	.pkt_access	= true,
> 
> ... this should both not be marked as pkt_access = true. What this means is that
> arg2, which is the struct bpf_fib_lookup, could come from the raw packet buffer.

leftover from the first version which did pass in the packet. Will remove.