Re: [PATCH bpf-next v6 5/6] bpf: Add selftests for raw syncookie helpers

[Maxim Mikityanskiy <maximmi@nvidia.com>]

On 2022-04-26 09:26, Andrii Nakryiko wrote:
> On Mon, Apr 25, 2022 at 5:12 PM Alexei Starovoitov
> <alexei.starovoitov@gmail.com> wrote:
>>
>> On Fri, Apr 22, 2022 at 08:24:21PM +0300, Maxim Mikityanskiy wrote:
>>> +void test_xdp_synproxy(void)
>>> +{
>>> +     int server_fd = -1, client_fd = -1, accept_fd = -1;
>>> +     struct nstoken *ns = NULL;
>>> +     FILE *ctrl_file = NULL;
>>> +     char buf[1024];
>>> +     size_t size;
>>> +
>>> +     SYS("ip netns add synproxy");
>>> +
>>> +     SYS("ip link add tmp0 type veth peer name tmp1");
>>> +     SYS("ip link set tmp1 netns synproxy");
>>> +     SYS("ip link set tmp0 up");
>>> +     SYS("ip addr replace 198.18.0.1/24 dev tmp0");
>>> +
>>> +     // When checksum offload is enabled, the XDP program sees wrong
>>> +     // checksums and drops packets.
>>> +     SYS("ethtool -K tmp0 tx off");
>>
>> BPF CI image doesn't have ethtool installed.
>> It will take some time to get it updated. Until then we cannot land the patch set.
>> Can you think of a way to run this test without shelling to ethtool?
> 
> Good news: we got updated CI image with ethtool, so that shouldn't be
> a problem anymore.
> 
> Bad news: this selftest still fails, but in different place:
> 
> test_synproxy:FAIL:iptables -t raw -I PREROUTING -i tmp1 -p tcp -m tcp
> --syn --dport 8080 -j CT --notrack unexpected error: 512 (errno 2)

That's simply a matter of missing kernel config options:

CONFIG_NETFILTER_SYNPROXY=y
CONFIG_NETFILTER_XT_TARGET_CT=y
CONFIG_NETFILTER_XT_MATCH_STATE=y
CONFIG_IP_NF_FILTER=y
CONFIG_IP_NF_TARGET_SYNPROXY=y
CONFIG_IP_NF_RAW=y

Shall I create a pull request on github to add these options to 
https://github.com/libbpf/libbpf/tree/master/travis-ci/vmtest/configs?

> See [0].
> 
>    [0] https://github.com/kernel-patches/bpf/runs/6169439612?check_suite_focus=true