[PATCH v5 5/9] landlock/selftests: Audit test for LANDLOCK_ACCESS_FS_RESOLVE_UNIX

["Günther Noack" <gnoack3000@gmail.com>]

Add an audit test to check that Landlock denials from
LANDLOCK_ACCESS_FS_RESOLVE_UNIX result in audit logs in the expected
format.  (There is one audit test for each filesystem access right, so
we should add one for LANDLOCK_ACCESS_FS_RESOLVE_UNIX as well.)

Signed-off-by: Günther Noack <gnoack3000@gmail.com>
---
 tools/testing/selftests/landlock/fs_test.c | 42 +++++++++++++++++++++-
 1 file changed, 41 insertions(+), 1 deletion(-)

diff --git a/tools/testing/selftests/landlock/fs_test.c b/tools/testing/selftests/landlock/fs_test.c
index bdeff2e0e029..8fa9d7c49ac3 100644
--- a/tools/testing/selftests/landlock/fs_test.c
+++ b/tools/testing/selftests/landlock/fs_test.c
@@ -7530,7 +7530,8 @@ static const __u64 access_fs_16 =
 	LANDLOCK_ACCESS_FS_MAKE_SYM |
 	LANDLOCK_ACCESS_FS_REFER |
 	LANDLOCK_ACCESS_FS_TRUNCATE |
-	LANDLOCK_ACCESS_FS_IOCTL_DEV;
+	LANDLOCK_ACCESS_FS_IOCTL_DEV |
+	LANDLOCK_ACCESS_FS_RESOLVE_UNIX;
 /* clang-format on */
 
 TEST_F(audit_layout1, execute_read)
@@ -7975,6 +7976,45 @@ TEST_F(audit_layout1, ioctl_dev)
 	EXPECT_EQ(1, records.domain);
 }
 
+TEST_F(audit_layout1, resolve_unix)
+{
+	struct audit_records records;
+	const char *const path = "sock";
+	int srv_fd, cli_fd, status;
+	pid_t child_pid;
+
+	srv_fd = set_up_named_unix_server(_metadata, SOCK_STREAM, path);
+
+	child_pid = fork();
+	ASSERT_LE(0, child_pid);
+	if (!child_pid) {
+		drop_access_rights(_metadata,
+				   &(struct landlock_ruleset_attr){
+					   .handled_access_fs = access_fs_16,
+				   });
+
+		cli_fd = socket(AF_UNIX, SOCK_STREAM, 0);
+		ASSERT_LE(0, cli_fd);
+		EXPECT_EQ(EACCES, test_connect_named_unix(cli_fd, path));
+
+		EXPECT_EQ(0, close(cli_fd));
+		_exit(_metadata->exit_code);
+	}
+
+	ASSERT_EQ(child_pid, waitpid(child_pid, &status, 0));
+	EXPECT_EQ(1, WIFEXITED(status));
+	EXPECT_EQ(EXIT_SUCCESS, WEXITSTATUS(status));
+
+	EXPECT_EQ(0, matches_log_fs_extra(_metadata, self->audit_fd,
+					  "fs\\.resolve_unix", path, NULL));
+
+	EXPECT_EQ(0, audit_count_records(self->audit_fd, &records));
+	EXPECT_EQ(0, records.access);
+	EXPECT_EQ(1, records.domain);
+
+	EXPECT_EQ(0, close(srv_fd));
+}
+
 TEST_F(audit_layout1, mount)
 {
 	struct audit_records records;
-- 
2.52.0