diff --git a/test/lib/Makefile b/test/lib/Makefile
index b6a0a20..ada62fe 100644
--- a/test/lib/Makefile
+++ b/test/lib/Makefile
@@ -3,6 +3,7 @@
 # (C) Copyright 2018
 # Mario Six, Guntermann & Drunck GmbH, mario.six@gdsys.cc
 obj-y += cmd_ut_lib.o
+obj-$(CONFIG_EFI_LOADER) += efi_device_path.o
 obj-$(CONFIG_EFI_SECURE_BOOT) += efi_image_region.o
 obj-y += hexdump.o
 obj-y += lmb.o
diff --git a/test/lib/efi_device_path.c b/test/lib/efi_device_path.c
new file mode 100644
index 0000000..24e2f23
--- /dev/null
+++ b/test/lib/efi_device_path.c
@@ -0,0 +1,50 @@
+// SPDX-License-Identifier: GPL-2.0+
+/*
+ * Test device path functions
+ *
+ * Copyright (c) 2020 Heinrich Schuchardt <xypron.glpk@gmx.de>
+ */
+
+#include <common.h>
+#include <efi_loader.h>
+#include <test/lib.h>
+#include <test/test.h>
+#include <test/ut.h>
+
+static int lib_test_efi_dp_check_length(struct unit_test_state *uts)
+{
+	/* end of device path */
+	u8 d1[] __aligned(2) = {
+		0x7f, 0xff, 0x04, 0x00 };
+	/* device path node with length less then 4 */
+	u8 d2[] __aligned(2) = {
+		0x01, 0x02, 0x02, 0x00, 0x04, 0x00, 0x7f, 0xff, 0x04, 0x00 };
+	/* well formed device path */
+	u8 d3[] __aligned(2) = {
+		0x03, 0x02, 0x08, 0x00, 0x01, 0x00, 0x01, 0x00,
+		0x7f, 0xff, 0x04, 0x00 };
+
+	struct efi_device_path *p1 = (struct efi_device_path *)d1;
+	struct efi_device_path *p2 = (struct efi_device_path *)d2;
+	struct efi_device_path *p3 = (struct efi_device_path *)d3;
+
+	ut_asserteq((ssize_t)-EINVAL, efi_dp_check_length(p1, SIZE_MAX));
+	ut_asserteq((ssize_t)sizeof(d1), efi_dp_check_length(p1, sizeof(d1)));
+	ut_asserteq((ssize_t)sizeof(d1),
+		    efi_dp_check_length(p1, sizeof(d1) + 4));
+	ut_asserteq((ssize_t)-1, efi_dp_check_length(p1, sizeof(d1) - 1));
+
+	ut_asserteq((ssize_t)-1, efi_dp_check_length(p2, sizeof(d2)));
+
+	ut_asserteq((ssize_t)-1, efi_dp_check_length(p3, sizeof(d3) - 1));
+	ut_asserteq((ssize_t)sizeof(d3), efi_dp_check_length(p3, sizeof(d3)));
+	ut_asserteq((ssize_t)sizeof(d3), efi_dp_check_length(p3, SSIZE_MAX));
+	ut_asserteq((ssize_t)-EINVAL,
+		    efi_dp_check_length(p3, (size_t)SSIZE_MAX + 1));
+	ut_asserteq((ssize_t)sizeof(d3),
+		    efi_dp_check_length(p3, sizeof(d3) + 4));
+
+	return 0;
+}
+
+LIB_TEST(lib_test_efi_dp_check_length, 0);