[PATCH v2 5/6] unicode: kunit: refactor selftest to kunit tests

Kees Cook
2025-02-11T00:31:37Z

From: Gabriela Bittencourt <gbittencourt@lkcamp.dev>

Refactoring 'test' functions into kunit tests, to test utf-8 support in
unicode subsystem.

This allows the utf8 tests to be run alongside the KUnit test suite
using kunit-tool, quickly compiling and running all desired tests as
part of the KUnit test suite, instead of compiling the selftest module
and loading it.

The refactoring kept the original testing logic intact, while adopting a
testing pattern across different kernel modules and leveraging KUnit's
benefits.

Co-developed-by: Pedro Orlando <porlando@lkcamp.dev>
Signed-off-by: Pedro Orlando <porlando@lkcamp.dev>
Co-developed-by: Danilo Pereira <dpereira@lkcamp.dev>
Signed-off-by: Danilo Pereira <dpereira@lkcamp.dev>
Signed-off-by: Gabriela Bittencourt <gbittencourt@lkcamp.dev>
Reviewed-by: David Gow <davidgow@google.com>
Acked-by: Gabriel Krisman Bertazi <krisman@suse.de>
Reviewed-by: Rae Moar <rmoar@google.com>
Link: https://lore.kernel.org/r/20241202075545.3648096-6-davidgow@google.com
Signed-off-by: Kees Cook <kees@kernel.org>
---
fs/unicode/.kunitconfig | 3 +
fs/unicode/Kconfig | 5 +-
fs/unicode/Makefile | 2 +-
fs/unicode/utf8-norm.c | 2 +-
fs/unicode/utf8-selftest.c | 149 +++++++++++++++++--------------------
5 files changed, 77 insertions(+), 84 deletions(-)
create mode 100644 fs/unicode/.kunitconfig

diff --git a/fs/unicode/.kunitconfig b/fs/unicode/.kunitconfig
new file mode 100644
index 000000000000..62dd5c171f9c
--- /dev/null
+++ b/fs/unicode/.kunitconfig
@@ -0,0 +1,3 @@
+CONFIG_KUNIT=y
+CONFIG_UNICODE=y
+CONFIG_UNICODE_NORMALIZATION_KUNIT_TEST=y
diff --git a/fs/unicode/Kconfig b/fs/unicode/Kconfig
index da786a687fdc..4ad2c36550f1 100644
--- a/fs/unicode/Kconfig
+++ b/fs/unicode/Kconfig
@@ -10,6 +10,7 @@ config UNICODE
be a separate loadable module that gets requested only when a file
system actually use it.

-config UNICODE_NORMALIZATION_SELFTEST
+config UNICODE_NORMALIZATION_KUNIT_TEST
tristate "Test UTF-8 normalization support"
- depends on UNICODE
+ depends on UNICODE && KUNIT
+ default KUNIT_ALL_TESTS
diff --git a/fs/unicode/Makefile b/fs/unicode/Makefile
index e309afe2b2bb..37bbcbc628a1 100644
--- a/fs/unicode/Makefile
+++ b/fs/unicode/Makefile
@@ -4,7 +4,7 @@ ifneq ($(CONFIG_UNICODE),)
obj-y += unicode.o
endif
obj-$(CONFIG_UNICODE) += utf8data.o
-obj-$(CONFIG_UNICODE_NORMALIZATION_SELFTEST) += utf8-selftest.o
+obj-$(CONFIG_UNICODE_NORMALIZATION_KUNIT_TEST) += utf8-selftest.o

unicode-y := utf8-norm.o utf8-core.o

diff --git a/fs/unicode/utf8-norm.c b/fs/unicode/utf8-norm.c
index 768f8ab448b8..7b998c99c88d 100644
--- a/fs/unicode/utf8-norm.c
+++ b/fs/unicode/utf8-norm.c
@@ -586,7 +586,7 @@ int utf8byte(struct utf8cursor *u8c)
}
}

-#ifdef CONFIG_UNICODE_NORMALIZATION_SELFTEST_MODULE
+#if IS_MODULE(CONFIG_UNICODE_NORMALIZATION_KUNIT_TEST)
EXPORT_SYMBOL_GPL(utf8version_is_supported);
EXPORT_SYMBOL_GPL(utf8nlen);
EXPORT_SYMBOL_GPL(utf8ncursor);
diff --git a/fs/unicode/utf8-selftest.c b/fs/unicode/utf8-selftest.c
index 5ddaf27b21a6..9476ab012baa 100644
--- a/fs/unicode/utf8-selftest.c
+++ b/fs/unicode/utf8-selftest.c
@@ -1,35 +1,15 @@
// SPDX-License-Identifier: GPL-2.0-only
/*
- * Kernel module for testing utf-8 support.
+ * KUnit tests for utf-8 support.
*
* Copyright 2017 Collabora Ltd.
*/

-#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
-
-#include <linux/module.h>
-#include <linux/printk.h>
#include <linux/unicode.h>
-#include <linux/dcache.h>
+#include <kunit/test.h>

#include "utf8n.h"

-static unsigned int failed_tests;
-static unsigned int total_tests;
-
-#define _test(cond, func, line, fmt, ...) do { \
- total_tests++; \
- if (!cond) { \
- failed_tests++; \
- pr_err("test %s:%d Failed: %s%s", \
- func, line, #cond, (fmt?":":".")); \
- if (fmt) \
- pr_err(fmt, ##__VA_ARGS__); \
- } \
- } while (0)
-#define test_f(cond, fmt, ...) _test(cond, __func__, __LINE__, fmt, ##__VA_ARGS__)
-#define test(cond) _test(cond, __func__, __LINE__, "")
-
static const struct {
/* UTF-8 strings in this vector _must_ be NULL-terminated. */
unsigned char str[10];
@@ -167,69 +147,74 @@ static int utf8cursor(struct utf8cursor *u8c, const struct unicode_map *um,
return utf8ncursor(u8c, um, n, s, (unsigned int)-1);
}

-static void check_utf8_nfdi(struct unicode_map *um)
+static void check_utf8_nfdi(struct kunit *test)
{
int i;
struct utf8cursor u8c;
+ struct unicode_map *um = test->priv;

for (i = 0; i < ARRAY_SIZE(nfdi_test_data); i++) {
int len = strlen(nfdi_test_data[i].str);
int nlen = strlen(nfdi_test_data[i].dec);
int j = 0;
unsigned char c;
+ int ret;
+
+ KUNIT_EXPECT_EQ(test, utf8len(um, UTF8_NFDI, nfdi_test_data[i].str), nlen);
+ KUNIT_EXPECT_EQ(test, utf8nlen(um, UTF8_NFDI, nfdi_test_data[i].str, len),
+ nlen);

- test((utf8len(um, UTF8_NFDI, nfdi_test_data[i].str) == nlen));
- test((utf8nlen(um, UTF8_NFDI, nfdi_test_data[i].str, len) ==
- nlen));

- if (utf8cursor(&u8c, um, UTF8_NFDI, nfdi_test_data[i].str) < 0)
- pr_err("can't create cursor\n");
+ ret = utf8cursor(&u8c, um, UTF8_NFDI, nfdi_test_data[i].str);
+ KUNIT_EXPECT_TRUE_MSG(test, ret >= 0, "Can't create cursor\n");

while ((c = utf8byte(&u8c)) > 0) {
- test_f((c == nfdi_test_data[i].dec[j]),
- "Unexpected byte 0x%x should be 0x%x\n",
- c, nfdi_test_data[i].dec[j]);
+ KUNIT_EXPECT_EQ_MSG(test, c, nfdi_test_data[i].dec[j],
+ "Unexpected byte 0x%x should be 0x%x\n",
+ c, nfdi_test_data[i].dec[j]);
j++;
}

- test((j == nlen));
+ KUNIT_EXPECT_EQ(test, j, nlen);
}
}

-static void check_utf8_nfdicf(struct unicode_map *um)
+static void check_utf8_nfdicf(struct kunit *test)
{
int i;
struct utf8cursor u8c;
+ struct unicode_map *um = test->priv;

for (i = 0; i < ARRAY_SIZE(nfdicf_test_data); i++) {
int len = strlen(nfdicf_test_data[i].str);
int nlen = strlen(nfdicf_test_data[i].ncf);
int j = 0;
+ int ret;
unsigned char c;

- test((utf8len(um, UTF8_NFDICF, nfdicf_test_data[i].str) ==
- nlen));
- test((utf8nlen(um, UTF8_NFDICF, nfdicf_test_data[i].str, len) ==
- nlen));
+ KUNIT_EXPECT_EQ(test, utf8len(um, UTF8_NFDICF, nfdicf_test_data[i].str),
+ nlen);
+ KUNIT_EXPECT_EQ(test, utf8nlen(um, UTF8_NFDICF, nfdicf_test_data[i].str, len),
+ nlen);

- if (utf8cursor(&u8c, um, UTF8_NFDICF,
- nfdicf_test_data[i].str) < 0)
- pr_err("can't create cursor\n");
+ ret = utf8cursor(&u8c, um, UTF8_NFDICF, nfdicf_test_data[i].str);
+ KUNIT_EXPECT_TRUE_MSG(test, ret >= 0, "Can't create cursor\n");

while ((c = utf8byte(&u8c)) > 0) {
- test_f((c == nfdicf_test_data[i].ncf[j]),
- "Unexpected byte 0x%x should be 0x%x\n",
- c, nfdicf_test_data[i].ncf[j]);
+ KUNIT_EXPECT_EQ_MSG(test, c, nfdicf_test_data[i].ncf[j],
+ "Unexpected byte 0x%x should be 0x%x\n",
+ c, nfdicf_test_data[i].ncf[j]);
j++;
}

- test((j == nlen));
+ KUNIT_EXPECT_EQ(test, j, nlen);
}
}

-static void check_utf8_comparisons(struct unicode_map *table)
+static void check_utf8_comparisons(struct kunit *test)
{
int i;
+ struct unicode_map *um = test->priv;

for (i = 0; i < ARRAY_SIZE(nfdi_test_data); i++) {
const struct qstr s1 = {.name = nfdi_test_data[i].str,
@@ -237,8 +222,9 @@ static void check_utf8_comparisons(struct unicode_map *table)
const struct qstr s2 = {.name = nfdi_test_data[i].dec,
.len = sizeof(nfdi_test_data[i].dec)};

- test_f(!utf8_strncmp(table, &s1, &s2),
- "%s %s comparison mismatch\n", s1.name, s2.name);
+ /* strncmp returns 0 when strings are equal */
+ KUNIT_EXPECT_TRUE_MSG(test, utf8_strncmp(um, &s1, &s2) == 0,
+ "%s %s comparison mismatch\n", s1.name, s2.name);
}

for (i = 0; i < ARRAY_SIZE(nfdicf_test_data); i++) {
@@ -247,62 +233,65 @@ static void check_utf8_comparisons(struct unicode_map *table)
const struct qstr s2 = {.name = nfdicf_test_data[i].ncf,
.len = sizeof(nfdicf_test_data[i].ncf)};

- test_f(!utf8_strncasecmp(table, &s1, &s2),
- "%s %s comparison mismatch\n", s1.name, s2.name);
+ /* strncasecmp returns 0 when strings are equal */
+ KUNIT_EXPECT_TRUE_MSG(test, utf8_strncasecmp(um, &s1, &s2) == 0,
+ "%s %s comparison mismatch\n", s1.name, s2.name);
}
}

-static void check_supported_versions(struct unicode_map *um)
+static void check_supported_versions(struct kunit *test)
{
+ struct unicode_map *um = test->priv;
/* Unicode 7.0.0 should be supported. */
- test(utf8version_is_supported(um, UNICODE_AGE(7, 0, 0)));
+ KUNIT_EXPECT_TRUE(test, utf8version_is_supported(um, UNICODE_AGE(7, 0, 0)));

/* Unicode 9.0.0 should be supported. */
- test(utf8version_is_supported(um, UNICODE_AGE(9, 0, 0)));
+ KUNIT_EXPECT_TRUE(test, utf8version_is_supported(um, UNICODE_AGE(9, 0, 0)));

/* Unicode 1x.0.0 (the latest version) should be supported. */
- test(utf8version_is_supported(um, UTF8_LATEST));
+ KUNIT_EXPECT_TRUE(test, utf8version_is_supported(um, UTF8_LATEST));

/* Next versions don't exist. */
- test(!utf8version_is_supported(um, UNICODE_AGE(13, 0, 0)));
- test(!utf8version_is_supported(um, UNICODE_AGE(0, 0, 0)));
- test(!utf8version_is_supported(um, UNICODE_AGE(-1, -1, -1)));
+ KUNIT_EXPECT_FALSE(test, utf8version_is_supported(um, UNICODE_AGE(13, 0, 0)));
+ KUNIT_EXPECT_FALSE(test, utf8version_is_supported(um, UNICODE_AGE(0, 0, 0)));
+ KUNIT_EXPECT_FALSE(test, utf8version_is_supported(um, UNICODE_AGE(-1, -1, -1)));
}

-static int __init init_test_ucd(void)
+static struct kunit_case unicode_normalization_test_cases[] = {
+ KUNIT_CASE(check_supported_versions),
+ KUNIT_CASE(check_utf8_comparisons),
+ KUNIT_CASE(check_utf8_nfdicf),
+ KUNIT_CASE(check_utf8_nfdi),
+ {}
+};
+
+static int init_test_ucd(struct kunit *test)
{
- struct unicode_map *um;
+ struct unicode_map *um = utf8_load(UTF8_LATEST);

- failed_tests = 0;
- total_tests = 0;
+ test->priv = um;

- um = utf8_load(UTF8_LATEST);
- if (IS_ERR(um)) {
- pr_err("%s: Unable to load utf8 table.\n", __func__);
- return PTR_ERR(um);
- }
+ KUNIT_EXPECT_EQ_MSG(test, IS_ERR(um), 0,
+ "%s: Unable to load utf8 table.\n", __func__);

- check_supported_versions(um);
- check_utf8_nfdi(um);
- check_utf8_nfdicf(um);
- check_utf8_comparisons(um);
-
- if (!failed_tests)
- pr_info("All %u tests passed\n", total_tests);
- else
- pr_err("%u out of %u tests failed\n", failed_tests,
- total_tests);
- utf8_unload(um);
return 0;
}

-static void __exit exit_test_ucd(void)
+static void exit_test_ucd(struct kunit *test)
{
+ utf8_unload(test->priv);
}

-module_init(init_test_ucd);
-module_exit(exit_test_ucd);
+static struct kunit_suite unicode_normalization_test_suite = {
+ .name = "unicode_normalization",
+ .test_cases = unicode_normalization_test_cases,
+ .init = init_test_ucd,
+ .exit = exit_test_ucd,
+};
+
+kunit_test_suite(unicode_normalization_test_suite);
+

MODULE_AUTHOR("Gabriel Krisman Bertazi <krisman@collabora.co.uk>");
-MODULE_DESCRIPTION("Kernel module for testing utf-8 support");
+MODULE_DESCRIPTION("KUnit tests for utf-8 support.");
MODULE_LICENSE("GPL");
--
2.34.1