Re: [PATCH bpf-next v3 3/4] selftests/bpf: integrate test_tc_tunnel.sh tests into test_progs

[Martin KaFai Lau <martin.lau@linux.dev>]

On 10/27/25 7:51 AM, Alexis Lothoré (eBPF Foundation) wrote:
> +static int run_server(struct subtest_cfg *cfg)
> +{
> +	struct nstoken *nstoken = open_netns(SERVER_NS);

It is unlikely but still better to check for open_netns failure. Just in 
case that the network changes/traffic is accidentally done in the 
original netns. There are a few netns switching in the test. Please 
followup.

> +	int family = cfg->ipproto == 6 ? AF_INET6 : AF_INET;
> +
> +	cfg->server_fd = start_reuseport_server(family, SOCK_STREAM,
> +						cfg->server_addr, TEST_PORT,
> +						TIMEOUT_MS, 1);

Why reuseport is needed? Does it have issue in bind() to the same 
ip/port in the later sub-test?
> +	close_netns(nstoken);
> +	if (!ASSERT_NEQ(cfg->server_fd, NULL, "start server"))

I changed the check to ASSERT_OK_PTR. Also two other similar 
ASSERT_[N]EQ(..., NULL, ...) usages.
> +		return -1;
> +
> +	return 0;
> +}
> +
> +static void stop_server(struct subtest_cfg *cfg)
> +{
> +	close(*cfg->server_fd);

NULL check on cfg->server_fd is needed during the error path of 
run_test(). cfg->server_fd is leaked also. I changed it to 
free_fds(cfg->server_fd, 1) instead.

> +	cfg->server_fd = NULL;

I don't think cfg will be reused, so I skip this NULL assignment.

> +}
> +
> +static int check_server_rx_data(struct subtest_cfg *cfg,
> +				struct connection *conn, int len)
> +{
> +	int err;
> +
> +	memset(rx_buffer, 0, BUFFER_LEN);
> +	err = recv(conn->server_fd, rx_buffer, len, 0);
> +	if (!ASSERT_EQ(err, len, "check rx data len"))
> +		return 1;
> +	if (!ASSERT_MEMEQ(tx_buffer, rx_buffer, len, "check received data"))
> +		return 1;
> +	return 0;
> +}
> +
> +static struct connection *connect_client_to_server(struct subtest_cfg *cfg)
> +{
> +	struct network_helper_opts opts = {.timeout_ms = 500};
> +	int family = cfg->ipproto == 6 ? AF_INET6 : AF_INET;
> +	struct connection *conn = NULL;
> +	int client_fd, server_fd;
> +
> +	conn = malloc(sizeof(struct connection));
> +	if (!conn)
> +		return conn;
> +
> +	client_fd = connect_to_addr_str(family, SOCK_STREAM, cfg->server_addr,
> +					TEST_PORT, &opts);
> +
> +	if (client_fd < 0) {
> +		free(conn);
> +		return NULL;
> +	}
> +
> +	server_fd = accept(*cfg->server_fd, NULL, NULL);
> +	if (server_fd < 0) {

Fixed the client_fd leak.
Applied. Thanks.