sock_map: Lift socket state restriction for datagram sockets

TCP and other connection oriented sockets have accept()
for each incoming connection on the server side, hence
they can just insert those fd's from accept() to sockmap,
which are of course established.

Now with datagram sockets begin to support sockmap and
redirection, the restriction is no longer applicable to
them, as they have no accept(). So we have to lift this
restriction for them. This is fine, because inside
bpf_sk_redirect_map() we still have another socket status
check, sock_map_redirect_allowed(), as a guard.

This also means they do not have to be removed from
sockmap when disconnecting.

Signed-off-by: Cong Wang <cong.wang@bytedance.com>
Signed-off-by: Alexei Starovoitov <ast@kernel.org>
Link: https://lore.kernel.org/bpf/20210704190252.11866-3-xiyou.wangcong@gmail.com

1 files changed, 5 insertions, 3 deletions

diff --git a/tools/testing/selftests/bpf/prog_tests/sockmap_listen.c b/tools/testing/selftests/bpf/prog_tests/sockmap_listen.c
index 515229f24a93..b8934ae694e5 100644
--- a/tools/testing/selftests/bpf/prog_tests/sockmap_listen.c
+++ b/tools/testing/selftests/bpf/prog_tests/sockmap_listen.c
@@ -351,9 +351,11 @@ static void test_insert_opened(int family, int sotype, int mapfd)
 	errno = 0;
 	value = s;
 	err = bpf_map_update_elem(mapfd, &key, &value, BPF_NOEXIST);
-	if (!err || errno != EOPNOTSUPP)
-		FAIL_ERRNO("map_update: expected EOPNOTSUPP");
-
+	if (sotype == SOCK_STREAM) {
+		if (!err || errno != EOPNOTSUPP)
+			FAIL_ERRNO("map_update: expected EOPNOTSUPP");
+	} else if (err)
+		FAIL_ERRNO("map_update: expected success");
 	xclose(s);
 }