Verify that for a connectible AF_VSOCK socket, merely having a transport
assigned is insufficient; socket must be connected for the sockmap to
accept.

This does not test datagram vsocks. Even though it hardly matters. VMCI is
the only transport that features VSOCK_TRANSPORT_F_DGRAM, but it has an
unimplemented vsock_transport::readskb() callback, making it unsupported by
BPF/sockmap.

Signed-off-by: Michal Luczaj <mhal@rbox.co>
---
 .../selftests/bpf/prog_tests/sockmap_basic.c       | 30 ++++++++++++++++++++++
 1 file changed, 30 insertions(+)

diff --git a/tools/testing/selftests/bpf/prog_tests/sockmap_basic.c b/tools/testing/selftests/bpf/prog_tests/sockmap_basic.c
index 21793d8c79e12b6e607f59ecebb26448c310044b..05eb37935c3e290ee52b8d8c7c3e3a8db026cba2 100644
--- a/tools/testing/selftests/bpf/prog_tests/sockmap_basic.c
+++ b/tools/testing/selftests/bpf/prog_tests/sockmap_basic.c
@@ -1065,6 +1065,34 @@ static void test_sockmap_skb_verdict_vsock_poll(void)
 	test_sockmap_pass_prog__destroy(skel);
 }
 
+static void test_sockmap_vsock_unconnected(void)
+{
+	struct sockaddr_storage addr;
+	int map, s, zero = 0;
+	socklen_t alen;
+
+	map = bpf_map_create(BPF_MAP_TYPE_SOCKMAP, NULL, sizeof(int),
+			     sizeof(int), 1, NULL);
+	if (!ASSERT_OK_FD(map, "bpf_map_create"))
+		return;
+
+	s = xsocket(AF_VSOCK, SOCK_STREAM, 0);
+	if (s < 0)
+		goto close_map;
+
+	/* Fail connect(), but trigger transport assignment. */
+	init_addr_loopback(AF_VSOCK, &addr, &alen);
+	if (!ASSERT_ERR(connect(s, sockaddr(&addr), alen), "connect"))
+		goto close_sock;
+
+	ASSERT_ERR(bpf_map_update_elem(map, &zero, &s, BPF_ANY), "map_update");
+
+close_sock:
+	xclose(s);
+close_map:
+	xclose(map);
+}
+
 void test_sockmap_basic(void)
 {
 	if (test__start_subtest("sockmap create_update_free"))
@@ -1131,4 +1159,6 @@ void test_sockmap_basic(void)
 		test_skmsg_helpers_with_link(BPF_MAP_TYPE_SOCKHASH);
 	if (test__start_subtest("sockmap skb_verdict vsock poll"))
 		test_sockmap_skb_verdict_vsock_poll();
+	if (test__start_subtest("sockmap vsock unconnected"))
+		test_sockmap_vsock_unconnected();
 }

-- 
2.48.1

On Thu, Feb 13, 2025 at 12:58:52PM +0100, Michal Luczaj wrote:
>Verify that for a connectible AF_VSOCK socket, merely having a transport
>assigned is insufficient; socket must be connected for the sockmap to
>accept.
>
>This does not test datagram vsocks. Even though it hardly matters. VMCI is
>the only transport that features VSOCK_TRANSPORT_F_DGRAM, but it has an
>unimplemented vsock_transport::readskb() callback, making it unsupported by
>BPF/sockmap.
>
>Signed-off-by: Michal Luczaj <mhal@rbox.co>
>---
> .../selftests/bpf/prog_tests/sockmap_basic.c       | 30 ++++++++++++++++++++++
> 1 file changed, 30 insertions(+)

Acked-by: Stefano Garzarella <sgarzare@redhat.com>

>
>diff --git a/tools/testing/selftests/bpf/prog_tests/sockmap_basic.c b/tools/testing/selftests/bpf/prog_tests/sockmap_basic.c
>index 21793d8c79e12b6e607f59ecebb26448c310044b..05eb37935c3e290ee52b8d8c7c3e3a8db026cba2 100644
>--- a/tools/testing/selftests/bpf/prog_tests/sockmap_basic.c
>+++ b/tools/testing/selftests/bpf/prog_tests/sockmap_basic.c
>@@ -1065,6 +1065,34 @@ static void test_sockmap_skb_verdict_vsock_poll(void)
> 	test_sockmap_pass_prog__destroy(skel);
> }
>
>+static void test_sockmap_vsock_unconnected(void)
>+{
>+	struct sockaddr_storage addr;
>+	int map, s, zero = 0;
>+	socklen_t alen;
>+
>+	map = bpf_map_create(BPF_MAP_TYPE_SOCKMAP, NULL, sizeof(int),
>+			     sizeof(int), 1, NULL);
>+	if (!ASSERT_OK_FD(map, "bpf_map_create"))
>+		return;
>+
>+	s = xsocket(AF_VSOCK, SOCK_STREAM, 0);
>+	if (s < 0)
>+		goto close_map;
>+
>+	/* Fail connect(), but trigger transport assignment. */
>+	init_addr_loopback(AF_VSOCK, &addr, &alen);
>+	if (!ASSERT_ERR(connect(s, sockaddr(&addr), alen), "connect"))
>+		goto close_sock;
>+
>+	ASSERT_ERR(bpf_map_update_elem(map, &zero, &s, BPF_ANY), "map_update");
>+
>+close_sock:
>+	xclose(s);
>+close_map:
>+	xclose(map);
>+}
>+
> void test_sockmap_basic(void)
> {
> 	if (test__start_subtest("sockmap create_update_free"))
>@@ -1131,4 +1159,6 @@ void test_sockmap_basic(void)
> 		test_skmsg_helpers_with_link(BPF_MAP_TYPE_SOCKHASH);
> 	if (test__start_subtest("sockmap skb_verdict vsock poll"))
> 		test_sockmap_skb_verdict_vsock_poll();
>+	if (test__start_subtest("sockmap vsock unconnected"))
>+		test_sockmap_vsock_unconnected();
> }
>
>-- 
>2.48.1
>

On 2/13/25 12:58, Michal Luczaj wrote:
> ...
> This does not test datagram vsocks. Even though it hardly matters. VMCI is
> the only transport that features VSOCK_TRANSPORT_F_DGRAM, but it has an
> unimplemented vsock_transport::readskb() callback, making it unsupported by
                                 ^^^^^^^
Ugh, read_skb().

Sorry,
Michal