[PATCH v1 2/2] selftests/landlock: Add tests to check unhandled rule's access rights

[Günther Noack]

On Mon, Nov 20, 2023 at 08:39:14PM +0100, Mickaël Salaün wrote:
> Add two tests to make sure that we cannot add a rule to a ruleset if the
> rule's access rights that are not handled by the ruleset:
> * fs: layout1.rule_with_unhandled_access
> * net: mini.rule_with_unhandled_access
> 
> Cc: Günther Noack <gnoack at google.com>
> Cc: Konstantin Meskhidze <konstantin.meskhidze at huawei.com>
> Signed-off-by: Mickaël Salaün <mic at digikod.net>
> ---
>  tools/testing/selftests/landlock/fs_test.c  | 35 +++++++++++++++++++++
>  tools/testing/selftests/landlock/net_test.c | 33 +++++++++++++++++++
>  2 files changed, 68 insertions(+)
> 
> diff --git a/tools/testing/selftests/landlock/fs_test.c b/tools/testing/selftests/landlock/fs_test.c
> index d77155d75de5..8cabcbe3554e 100644
> --- a/tools/testing/selftests/landlock/fs_test.c
> +++ b/tools/testing/selftests/landlock/fs_test.c
> @@ -596,6 +596,41 @@ TEST_F_FORK(layout1, file_and_dir_access_rights)
>  	ASSERT_EQ(0, close(ruleset_fd));
>  }
>  
> +TEST_F_FORK(layout1, rule_with_unhandled_access)
> +{
> +	struct landlock_ruleset_attr ruleset_attr = {
> +		/* First bit */
> +		.handled_access_fs = LANDLOCK_ACCESS_FS_EXECUTE,

Optional nit: If you want to spell out that this is 1, you could as well add an
assertion for that.  Doesn't even need to be a static_assert, it's just a test
after all.  Or maybe even put a literal 1 here instead. :)

> +	};
> +	struct landlock_path_beneath_attr path_beneath = {};
> +	int ruleset_fd;
> +	__u64 access;
> +
> +	ruleset_fd =
> +		landlock_create_ruleset(&ruleset_attr, sizeof(ruleset_attr), 0);
> +	ASSERT_LE(0, ruleset_fd);
> +
> +	path_beneath.parent_fd = open(file1_s1d2, O_PATH | O_CLOEXEC);
> +	ASSERT_LE(0, path_beneath.parent_fd);
> +
> +	for (access = 1; access > 0; access <<= 1) {
> +		int err;
> +
> +		path_beneath.allowed_access = access;
> +		err = landlock_add_rule(ruleset_fd, LANDLOCK_RULE_PATH_BENEATH,
> +					&path_beneath, 0);
> +		if (access == ruleset_attr.handled_access_fs) {
> +			EXPECT_EQ(0, err);
> +		} else {
> +			EXPECT_EQ(-1, err);
> +			EXPECT_EQ(EINVAL, errno);
> +		}
> +	}
> +
> +	EXPECT_EQ(0, close(path_beneath.parent_fd));
> +	EXPECT_EQ(0, close(ruleset_fd));
> +}
> +
>  TEST_F_FORK(layout0, unknown_access_rights)
>  {
>  	__u64 access_mask;
> diff --git a/tools/testing/selftests/landlock/net_test.c b/tools/testing/selftests/landlock/net_test.c
> index 9356f5800e31..aec01917abd5 100644
> --- a/tools/testing/selftests/landlock/net_test.c
> +++ b/tools/testing/selftests/landlock/net_test.c
> @@ -1262,6 +1262,39 @@ TEST_F(mini, network_access_rights)
>  	EXPECT_EQ(0, close(ruleset_fd));
>  }
>  
> +TEST_F(mini, rule_with_unhandled_access)
> +{
> +	struct landlock_ruleset_attr ruleset_attr = {
> +		/* First bit */
> +		.handled_access_net = LANDLOCK_ACCESS_NET_BIND_TCP,

Ditto.

> +	};
> +	struct landlock_net_port_attr net_port = {
> +		.port = sock_port_start,
> +	};
> +	int ruleset_fd;
> +	__u64 access;
> +
> +	ruleset_fd =
> +		landlock_create_ruleset(&ruleset_attr, sizeof(ruleset_attr), 0);
> +	ASSERT_LE(0, ruleset_fd);
> +
> +	for (access = 1; access > 0; access <<= 1) {
> +		int err;
> +
> +		net_port.allowed_access = access;
> +		err = landlock_add_rule(ruleset_fd, LANDLOCK_RULE_NET_PORT,
> +					&net_port, 0);
> +		if (access == ruleset_attr.handled_access_net) {
> +			EXPECT_EQ(0, err);
> +		} else {
> +			EXPECT_EQ(-1, err);
> +			EXPECT_EQ(EINVAL, errno);
> +		}
> +	}
> +
> +	EXPECT_EQ(0, close(ruleset_fd));
> +}
> +
>  /* Checks invalid attribute, out of landlock network access range. */
>  TEST_F(mini, unknown_access_rights)
>  {
> -- 
> 2.42.1
> 

Reviewed-by: Günther Noack <gnoack at google.com>

Thanks for the tests!
—Günther