diff --git a/lib/test-string_helpers.c b/lib/test-string_helpers.c
new file mode 100644
index 0000000..25b5cbf
--- /dev/null
+++ b/lib/test-string_helpers.c
@@ -0,0 +1,417 @@
+/*
+ * Test cases for lib/string_helpers.c module.
+ */
+#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
+
+#include <linux/init.h>
+#include <linux/kernel.h>
+#include <linux/slab.h>
+#include <linux/module.h>
+#include <linux/random.h>
+#include <linux/string.h>
+#include <linux/string_helpers.h>
+
+static __init bool test_string_check_buf(const char *name, unsigned int flags,
+					 char *in, size_t p,
+					 char *out_real, size_t q_real,
+					 char *out_test, size_t q_test)
+{
+	if (q_real == q_test && !memcmp(out_test, out_real, q_test))
+		return true;
+
+	pr_warn("Test '%s' failed: flags = %u\n", name, flags);
+
+	print_hex_dump(KERN_WARNING, "Input: ", DUMP_PREFIX_NONE, 16, 1,
+		       in, p, true);
+	print_hex_dump(KERN_WARNING, "Expected: ", DUMP_PREFIX_NONE, 16, 1,
+		       out_test, q_test, true);
+	print_hex_dump(KERN_WARNING, "Got: ", DUMP_PREFIX_NONE, 16, 1,
+		       out_real, q_real, true);
+
+	return false;
+}
+
+struct test_string {
+	const char *in;
+	const char *out;
+	unsigned int flags;
+};
+
+static const struct test_string strings[] __initconst = {
+	{
+		.in = "\\f\\ \\n\\r\\t\\v",
+		.out = "\f\\ \n\r\t\v",
+		.flags = UNESCAPE_SPACE,
+	},
+	{
+		.in = "\\40\\1\\387\\0064\\05\\040\\8a\\110\\777",
+		.out = " \001\00387\0064\005 \\8aH?7",
+		.flags = UNESCAPE_OCTAL,
+	},
+	{
+		.in = "\\xv\\xa\\x2c\\xD\\x6f2",
+		.out = "\\xv\n,\ro2",
+		.flags = UNESCAPE_HEX,
+	},
+	{
+		.in = "\\h\\\\\\\"\\a\\e\\",
+		.out = "\\h\\\"\a\e\\",
+		.flags = UNESCAPE_SPECIAL,
+	},
+};
+
+static void __init test_string_unescape(const char *name, unsigned int flags,
+					bool inplace)
+{
+	int q_real = 256;
+	char *in = kmalloc(q_real, GFP_KERNEL);
+	char *out_test = kmalloc(q_real, GFP_KERNEL);
+	char *out_real = kmalloc(q_real, GFP_KERNEL);
+	int i, p = 0, q_test = 0;
+
+	if (!in || !out_test || !out_real)
+		goto out;
+
+	for (i = 0; i < ARRAY_SIZE(strings); i++) {
+		const char *s = strings[i].in;
+		int len = strlen(strings[i].in);
+
+		/* Copy string to in buffer */
+		memcpy(&in[p], s, len);
+		p += len;
+
+		/* Copy expected result for given flags */
+		if (flags & strings[i].flags) {
+			s = strings[i].out;
+			len = strlen(strings[i].out);
+		}
+		memcpy(&out_test[q_test], s, len);
+		q_test += len;
+	}
+	in[p++] = '\0';
+
+	/* Call string_unescape and compare result */
+	if (inplace) {
+		memcpy(out_real, in, p);
+		if (flags == UNESCAPE_ANY)
+			q_real = string_unescape_any_inplace(out_real);
+		else
+			q_real = string_unescape_inplace(out_real, flags);
+	} else if (flags == UNESCAPE_ANY) {
+		q_real = string_unescape_any(in, out_real, q_real);
+	} else {
+		q_real = string_unescape(in, out_real, q_real, flags);
+	}
+
+	test_string_check_buf(name, flags, in, p - 1, out_real, q_real,
+			      out_test, q_test);
+out:
+	kfree(out_real);
+	kfree(out_test);
+	kfree(in);
+}
+
+struct test_string_1 {
+	const char *out;
+	unsigned int flags;
+};
+
+#define	TEST_STRING_2_MAX_S1		32
+struct test_string_2 {
+	const char *in;
+	struct test_string_1 s1[TEST_STRING_2_MAX_S1];
+};
+
+#define	TEST_STRING_2_DICT_0		NULL
+static const struct test_string_2 escape0[] __initconst = {{
+	.in = "\f\\ \n\r\t\v",
+	.s1 = {{
+		.out = "\\f\\ \\n\\r\\t\\v",
+		.flags = ESCAPE_SPACE,
+	},{
+		.out = "\\f\\134\\040\\n\\r\\t\\v",
+		.flags = ESCAPE_SPACE | ESCAPE_OCTAL,
+	},{
+		.out = "\\f\\x5c\\x20\\n\\r\\t\\v",
+		.flags = ESCAPE_SPACE | ESCAPE_HEX,
+	},{
+		/* terminator */
+	}},
+},{
+	.in = "\\h\\\"\a\e\\",
+	.s1 = {{
+		.out = "\\\\h\\\\\"\\a\\e\\\\",
+		.flags = ESCAPE_SPECIAL,
+	},{
+		.out = "\\\\\\150\\\\\\042\\a\\e\\\\",
+		.flags = ESCAPE_SPECIAL | ESCAPE_OCTAL,
+	},{
+		.out = "\\\\\\x68\\\\\\x22\\a\\e\\\\",
+		.flags = ESCAPE_SPECIAL | ESCAPE_HEX,
+	},{
+		/* terminator */
+	}},
+},{
+	.in = "\eb \\C\007\"\x90\r]",
+	.s1 = {{
+		.out = "\eb \\C\007\"\x90\\r]",
+		.flags = ESCAPE_SPACE,
+	},{
+		.out = "\\eb \\\\C\\a\"\x90\r]",
+		.flags = ESCAPE_SPECIAL,
+	},{
+		.out = "\\eb \\\\C\\a\"\x90\\r]",
+		.flags = ESCAPE_SPACE | ESCAPE_SPECIAL,
+	},{
+		.out = "\\033\\142\\040\\134\\103\\007\\042\\220\\015\\135",
+		.flags = ESCAPE_OCTAL,
+	},{
+		.out = "\\033\\142\\040\\134\\103\\007\\042\\220\\r\\135",
+		.flags = ESCAPE_SPACE | ESCAPE_OCTAL,
+	},{
+		.out = "\\e\\142\\040\\\\\\103\\a\\042\\220\\015\\135",
+		.flags = ESCAPE_SPECIAL | ESCAPE_OCTAL,
+	},{
+		.out = "\\e\\142\\040\\\\\\103\\a\\042\\220\\r\\135",
+		.flags = ESCAPE_SPACE | ESCAPE_SPECIAL | ESCAPE_OCTAL,
+	},{
+		.out = "\eb \\C\007\"\x90\r]",
+		.flags = ESCAPE_NP,
+	},{
+		.out = "\eb \\C\007\"\x90\\r]",
+		.flags = ESCAPE_SPACE | ESCAPE_NP,
+	},{
+		.out = "\\eb \\C\\a\"\x90\r]",
+		.flags = ESCAPE_SPECIAL | ESCAPE_NP,
+	},{
+		.out = "\\eb \\C\\a\"\x90\\r]",
+		.flags = ESCAPE_SPACE | ESCAPE_SPECIAL | ESCAPE_NP,
+	},{
+		.out = "\\033b \\C\\007\"\\220\\015]",
+		.flags = ESCAPE_OCTAL | ESCAPE_NP,
+	},{
+		.out = "\\033b \\C\\007\"\\220\\r]",
+		.flags = ESCAPE_SPACE | ESCAPE_OCTAL | ESCAPE_NP,
+	},{
+		.out = "\\eb \\C\\a\"\\220\\r]",
+		.flags = ESCAPE_SPECIAL | ESCAPE_SPACE | ESCAPE_OCTAL |
+			 ESCAPE_NP,
+	},{
+		.out = "\\x1bb \\C\\x07\"\\x90\\x0d]",
+		.flags = ESCAPE_NP | ESCAPE_HEX,
+	},{
+		/* terminator */
+	}},
+},{
+	/* terminator */
+}};
+
+#define	TEST_STRING_2_DICT_1		"b\\ \t\r"
+static const struct test_string_2 escape1[] __initconst = {{
+	.in = "\f\\ \n\r\t\v",
+	.s1 = {{
+		.out = "\f\\134\\040\n\\015\\011\v",
+		.flags = ESCAPE_OCTAL,
+	},{
+		.out = "\f\\x5c\\x20\n\\x0d\\x09\v",
+		.flags = ESCAPE_HEX,
+	},{
+		/* terminator */
+	}},
+},{
+	.in = "\\h\\\"\a\e\\",
+	.s1 = {{
+		.out = "\\134h\\134\"\a\e\\134",
+		.flags = ESCAPE_OCTAL,
+	},{
+		/* terminator */
+	}},
+},{
+	.in = "\eb \\C\007\"\x90\r]",
+	.s1 = {{
+		.out = "\e\\142\\040\\134C\007\"\x90\\015]",
+		.flags = ESCAPE_OCTAL,
+	},{
+		/* terminator */
+	}},
+},{
+	/* terminator */
+}};
+
+static __init const char *test_string_find_match(const struct test_string_2 *s2,
+						 unsigned int flags)
+{
+	const struct test_string_1 *s1 = s2->s1;
+	unsigned int i;
+
+	if (!flags)
+		return s2->in;
+
+	/* Test cases are NULL-aware */
+	flags &= ~ESCAPE_NULL;
+
+	/* ESCAPE_OCTAL has a higher priority */
+	if (flags & ESCAPE_OCTAL)
+		flags &= ~ESCAPE_HEX;
+
+	for (i = 0; i < TEST_STRING_2_MAX_S1 && s1->out; i++, s1++)
+		if (s1->flags == flags)
+			return s1->out;
+	return NULL;
+}
+
+static __init void
+test_string_escape_overflow(const char *in, int p, unsigned int flags, const char *esc,
+			    int q_test, const char *name)
+{
+	int q_real;
+
+	q_real = string_escape_mem(in, p, NULL, 0, flags, esc);
+	if (q_real != q_test)
+		pr_warn("Test '%s' failed: flags = %u, osz = 0, expected %d, got %d\n",
+			name, flags, q_test, q_real);
+}
+
+static __init void test_string_escape(const char *name,
+				      const struct test_string_2 *s2,
+				      unsigned int flags, const char *esc)
+{
+	size_t out_size = 512;
+	char *out_test = kmalloc(out_size, GFP_KERNEL);
+	char *out_real = kmalloc(out_size, GFP_KERNEL);
+	char *in = kmalloc(256, GFP_KERNEL);
+	int p = 0, q_test = 0;
+	int q_real;
+
+	if (!out_test || !out_real || !in)
+		goto out;
+
+	for (; s2->in; s2++) {
+		const char *out;
+		int len;
+
+		/* NULL injection */
+		if (flags & ESCAPE_NULL) {
+			in[p++] = '\0';
+			out_test[q_test++] = '\\';
+			out_test[q_test++] = '0';
+		}
+
+		/* Don't try strings that have no output */
+		out = test_string_find_match(s2, flags);
+		if (!out)
+			continue;
+
+		/* Copy string to in buffer */
+		len = strlen(s2->in);
+		memcpy(&in[p], s2->in, len);
+		p += len;
+
+		/* Copy expected result for given flags */
+		len = strlen(out);
+		memcpy(&out_test[q_test], out, len);
+		q_test += len;
+	}
+
+	q_real = string_escape_mem(in, p, out_real, out_size, flags, esc);
+
+	test_string_check_buf(name, flags, in, p, out_real, q_real, out_test,
+			      q_test);
+
+	test_string_escape_overflow(in, p, flags, esc, q_test, name);
+
+out:
+	kfree(in);
+	kfree(out_real);
+	kfree(out_test);
+}
+
+#define string_get_size_maxbuf 16
+#define test_string_get_size_one(size, blk_size, exp_result10, exp_result2)    \
+	do {                                                                   \
+		BUILD_BUG_ON(sizeof(exp_result10) >= string_get_size_maxbuf);  \
+		BUILD_BUG_ON(sizeof(exp_result2) >= string_get_size_maxbuf);   \
+		__test_string_get_size((size), (blk_size), (exp_result10),     \
+				       (exp_result2));                         \
+	} while (0)
+
+
+static __init void test_string_get_size_check(const char *units,
+					      const char *exp,
+					      char *res,
+					      const u64 size,
+					      const u64 blk_size)
+{
+	if (!memcmp(res, exp, strlen(exp) + 1))
+		return;
+
+	res[string_get_size_maxbuf - 1] = '\0';
+
+	pr_warn("Test 'test_string_get_size' failed!\n");
+	pr_warn("string_get_size(size = %llu, blk_size = %llu, units = %s)\n",
+		size, blk_size, units);
+	pr_warn("expected: '%s', got '%s'\n", exp, res);
+}
+
+static __init void __test_string_get_size(const u64 size, const u64 blk_size,
+					  const char *exp_result10,
+					  const char *exp_result2)
+{
+	char buf10[string_get_size_maxbuf];
+	char buf2[string_get_size_maxbuf];
+
+	string_get_size(size, blk_size, STRING_UNITS_10, buf10, sizeof(buf10));
+	string_get_size(size, blk_size, STRING_UNITS_2, buf2, sizeof(buf2));
+
+	test_string_get_size_check("STRING_UNITS_10", exp_result10, buf10,
+				   size, blk_size);
+
+	test_string_get_size_check("STRING_UNITS_2", exp_result2, buf2,
+				   size, blk_size);
+}
+
+static __init void test_string_get_size(void)
+{
+	/* small values */
+	test_string_get_size_one(0, 512, "0 B", "0 B");
+	test_string_get_size_one(1, 512, "512 B", "512 B");
+	test_string_get_size_one(1100, 1, "1.10 kB", "1.07 KiB");
+
+	/* normal values */
+	test_string_get_size_one(16384, 512, "8.39 MB", "8.00 MiB");
+	test_string_get_size_one(500118192, 512, "256 GB", "238 GiB");
+	test_string_get_size_one(8192, 4096, "33.6 MB", "32.0 MiB");
+
+	/* weird block sizes */
+	test_string_get_size_one(3000, 1900, "5.70 MB", "5.44 MiB");
+
+	/* huge values */
+	test_string_get_size_one(U64_MAX, 4096, "75.6 ZB", "64.0 ZiB");
+	test_string_get_size_one(4096, U64_MAX, "75.6 ZB", "64.0 ZiB");
+}
+
+static int __init test_string_helpers_init(void)
+{
+	unsigned int i;
+
+	pr_info("Running tests...\n");
+	for (i = 0; i < UNESCAPE_ANY + 1; i++)
+		test_string_unescape("unescape", i, false);
+	test_string_unescape("unescape inplace",
+			     get_random_int() % (UNESCAPE_ANY + 1), true);
+
+	/* Without dictionary */
+	for (i = 0; i < (ESCAPE_ANY_NP | ESCAPE_HEX) + 1; i++)
+		test_string_escape("escape 0", escape0, i, TEST_STRING_2_DICT_0);
+
+	/* With dictionary */
+	for (i = 0; i < (ESCAPE_ANY_NP | ESCAPE_HEX) + 1; i++)
+		test_string_escape("escape 1", escape1, i, TEST_STRING_2_DICT_1);
+
+	/* Test string_get_size() */
+	test_string_get_size();
+
+	return -EINVAL;
+}
+module_init(test_string_helpers_init);
+MODULE_LICENSE("Dual BSD/GPL");