[RFC PATCH v1 5/9] selftests/landlock: Test listen on connected socket

[Mikhail Ivanov]

8/1/2024 5:46 PM, Mickaël Salaün wrote:
> On Sun, Jul 28, 2024 at 08:25:58AM +0800, Mikhail Ivanov wrote:
>> Test checks that listen(2) doesn't wrongfully return -EACCES instead
>> of -EINVAL when trying to listen for an incorrect socket state.
>>
>> Signed-off-by: Mikhail Ivanov <ivanov.mikhail1 at huawei-partners.com>
> 
> Good to have this test!
> 
>> ---
>>   tools/testing/selftests/landlock/net_test.c | 65 +++++++++++++++++++++
>>   1 file changed, 65 insertions(+)
>>
>> diff --git a/tools/testing/selftests/landlock/net_test.c b/tools/testing/selftests/landlock/net_test.c
>> index b6fe9bde205f..a8385f1373f6 100644
>> --- a/tools/testing/selftests/landlock/net_test.c
>> +++ b/tools/testing/selftests/landlock/net_test.c
>> @@ -1644,6 +1644,71 @@ TEST_F(ipv4_tcp, with_fs)
>>   	EXPECT_EQ(-EACCES, bind_variant(bind_fd, &self->srv1));
>>   }
>>   
>> +TEST_F(ipv4_tcp, listen_on_connected)
> 
> We should use the "protocol" fixture and its variants instead to test
> with different protocols and also without sandboxing (which is crutial).
> 
> I guess espintcp_listen should use "protocol" too.
> 
> ipv4_tcp is to run tests that only make sense on an IPv4 socket, but
> when we test EINVAL, we should make sure Landlock doesn't introduce
> inconsistencies for other/unsupported protocols.

Makes sense, let's use "protocol".

> 
>> +{
>> +	const struct landlock_ruleset_attr ruleset_attr = {
>> +		.handled_access_net = ACCESS_ALL,
>> +	};
>> +	const struct landlock_net_port_attr tcp_not_restricted_p0 = {
>> +		.allowed_access = ACCESS_ALL,
>> +		.port = self->srv0.port,
>> +	};
>> +	const struct landlock_net_port_attr tcp_denied_listen_p1 = {
>> +		.allowed_access = ACCESS_ALL & ~LANDLOCK_ACCESS_NET_LISTEN_TCP,
>> +		.port = self->srv1.port,
>> +	};
>> +	int ruleset_fd;
>> +	int bind_fd, status;
>> +	pid_t child;
>> +
>> +	ruleset_fd =
>> +		landlock_create_ruleset(&ruleset_attr, sizeof(ruleset_attr), 0);
>> +	ASSERT_LE(0, ruleset_fd);
>> +
>> +	/* Allows all actions for the first port. */
>> +	ASSERT_EQ(0, landlock_add_rule(ruleset_fd, LANDLOCK_RULE_NET_PORT,
>> +				       &tcp_not_restricted_p0, 0));
>> +
>> +	/* Deny listen for the second port. */
> 
> nit: Denies listening

will be fixed

> 
>> +	ASSERT_EQ(0, landlock_add_rule(ruleset_fd, LANDLOCK_RULE_NET_PORT,
>> +				       &tcp_denied_listen_p1, 0));
>> +
>> +	enforce_ruleset(_metadata, ruleset_fd);
>> +	EXPECT_EQ(0, close(ruleset_fd));
>> +
>> +	/* Init listening socket. */
> 
> nit: Initializes

will be fixed

> 
>> +	bind_fd = socket_variant(&self->srv0);
>> +	ASSERT_LE(0, bind_fd);
>> +	EXPECT_EQ(0, bind_variant(bind_fd, &self->srv0));
>> +	EXPECT_EQ(0, listen_variant(bind_fd, backlog));
>> +
>> +	child = fork();
>> +	ASSERT_LE(0, child);
>> +	if (child == 0) {
>> +		int connect_fd;
>> +
>> +		/* Closes listening socket for the child. */
>> +		EXPECT_EQ(0, close(bind_fd));
>> +
>> +		connect_fd = socket_variant(&self->srv1);
>> +		ASSERT_LE(0, connect_fd);
>> +		EXPECT_EQ(0, connect_variant(connect_fd, &self->srv0));
>> +
>> +		/* Tries to listen on connected socket. */
>> +		EXPECT_EQ(-EINVAL, listen_variant(connect_fd, backlog));
>> +
>> +		EXPECT_EQ(0, close(connect_fd));
>> +		_exit(_metadata->exit_code);
>> +		return;
>> +	}
>> +
>> +	EXPECT_EQ(child, waitpid(child, &status, 0));
>> +	EXPECT_EQ(1, WIFEXITED(status));
>> +	EXPECT_EQ(EXIT_SUCCESS, WEXITSTATUS(status));
>> +
>> +	EXPECT_EQ(0, close(bind_fd));
>> +}
>> +
>>   FIXTURE(port_specific)
>>   {
>>   	struct service_fixture srv0;
>> -- 
>> 2.34.1
>>
>>