Re: [PATCH bpf-next] selftests/bpf: run mptcp in a dedicated netns

[Larysa Zaremba <larysa.zaremba@intel.com>]

On Fri, Feb 17, 2023 at 04:26:07PM +0800, Hangbin Liu wrote:
> The current mptcp test is run in init netns. If the user or default
> system config disabled mptcp, the test will fail. Let's run the mptcp
> test in a dedicated netns to avoid none kernel default mptcp setting.
> 
> Suggested-by: Martin KaFai Lau <martin.lau@linux.dev>

Reviewed-by: Larysa Zaremba <larysa.zaremba@intel.com>

> Signed-off-by: Hangbin Liu <liuhangbin@gmail.com>
> ---
>  .../testing/selftests/bpf/prog_tests/mptcp.c  | 24 +++++++++++++++++++
>  1 file changed, 24 insertions(+)
> 
> diff --git a/tools/testing/selftests/bpf/prog_tests/mptcp.c b/tools/testing/selftests/bpf/prog_tests/mptcp.c
> index 59f08d6d1d53..8a4ed9510ec7 100644
> --- a/tools/testing/selftests/bpf/prog_tests/mptcp.c
> +++ b/tools/testing/selftests/bpf/prog_tests/mptcp.c
> @@ -7,6 +7,16 @@
>  #include "network_helpers.h"
>  #include "mptcp_sock.skel.h"
>  
> +#define SYS(fmt, ...)						\
> +	({							\
> +		char cmd[1024];					\
> +		snprintf(cmd, sizeof(cmd), fmt, ##__VA_ARGS__);	\
> +		if (!ASSERT_OK(system(cmd), cmd))		\
> +			goto cmd_fail;				\
> +	})
> +
> +#define NS_TEST "mptcp_ns"
> +
>  #ifndef TCP_CA_NAME_MAX
>  #define TCP_CA_NAME_MAX	16
>  #endif
> @@ -138,12 +148,20 @@ static int run_test(int cgroup_fd, int server_fd, bool is_mptcp)
>  
>  static void test_base(void)
>  {
> +	struct nstoken *nstoken = NULL;
>  	int server_fd, cgroup_fd;
>  
>  	cgroup_fd = test__join_cgroup("/mptcp");
>  	if (!ASSERT_GE(cgroup_fd, 0, "test__join_cgroup"))
>  		return;
>  
> +	SYS("ip netns add %s", NS_TEST);
> +	SYS("ip -net %s link set dev lo up", NS_TEST);
> +
> +	nstoken = open_netns(NS_TEST);
> +	if (!ASSERT_OK_PTR(nstoken, "open_netns"))
> +		goto cmd_fail;
> +
>  	/* without MPTCP */
>  	server_fd = start_server(AF_INET, SOCK_STREAM, NULL, 0, 0);
>  	if (!ASSERT_GE(server_fd, 0, "start_server"))
> @@ -163,6 +181,12 @@ static void test_base(void)
>  
>  	close(server_fd);
>  
> +cmd_fail:
> +	if (nstoken)
> +		close_netns(nstoken);
> +
> +	system("ip netns del " NS_TEST " >& /dev/null");
> +
>  close_cgroup_fd:
>  	close(cgroup_fd);
>  }
> -- 
> 2.38.1
>