selftests/bpf: Allow auto port binding for bpf nf

Allow auto port binding for bpf nf test to avoid binding conflict.

./test_progs -a bpf_nf
24/1    bpf_nf/xdp-ct:OK
24/2    bpf_nf/tc-bpf-ct:OK
24/3    bpf_nf/alloc_release:OK
24/4    bpf_nf/insert_insert:OK
24/5    bpf_nf/lookup_insert:OK
24/6    bpf_nf/set_timeout_after_insert:OK
24/7    bpf_nf/set_status_after_insert:OK
24/8    bpf_nf/change_timeout_after_alloc:OK
24/9    bpf_nf/change_status_after_alloc:OK
24/10   bpf_nf/write_not_allowlisted_field:OK
24      bpf_nf:OK
Summary: 1/10 PASSED, 0 SKIPPED, 0 FAILED

Signed-off-by: Jiayuan Chen <jiayuan.chen@linux.dev>
Link: https://lore.kernel.org/r/20250227142646.59711-3-jiayuan.chen@linux.dev
Signed-off-by: Alexei Starovoitov <ast@kernel.org>

diff --git a/tools/testing/selftests/bpf/prog_tests/bpf_nf.c b/tools/testing/selftests/bpf/prog_tests/bpf_nf.c
index a4a1f93878d40dceed5cb41f6c03c60b39fbc96d..dbd13f8e42a7aa712cb58dbffd484f5e373609ab 100644 (file)
--- a/tools/testing/selftests/bpf/prog_tests/bpf_nf.c
+++ b/tools/testing/selftests/bpf/prog_tests/bpf_nf.c
@@ -72,11 +72,14 @@ static void test_bpf_nf_ct(int mode)
        if (!ASSERT_OK(system(cmd), cmd))
                goto end;
 
-       srv_port = (mode == TEST_XDP) ? 5005 : 5006;
-       srv_fd = start_server(AF_INET, SOCK_STREAM, "127.0.0.1", srv_port, TIMEOUT_MS);
+       srv_fd = start_server(AF_INET, SOCK_STREAM, "127.0.0.1", 0, TIMEOUT_MS);
        if (!ASSERT_GE(srv_fd, 0, "start_server"))
                goto end;
 
+       srv_port = get_socket_local_port(srv_fd);
+       if (!ASSERT_GE(srv_port, 0, "get_sock_local_port"))
+               goto end;
+
        client_fd = connect_to_server(srv_fd);
        if (!ASSERT_GE(client_fd, 0, "connect_to_server"))
                goto end;
@@ -91,7 +94,7 @@ static void test_bpf_nf_ct(int mode)
        skel->bss->saddr = peer_addr.sin_addr.s_addr;
        skel->bss->sport = peer_addr.sin_port;
        skel->bss->daddr = peer_addr.sin_addr.s_addr;
-       skel->bss->dport = htons(srv_port);
+       skel->bss->dport = srv_port;
 
        if (mode == TEST_XDP)
                prog_fd = bpf_program__fd(skel->progs.nf_xdp_ct_test);