diff options
| author | Feng Jiang <jiangfeng@kylinos.cn> | 2026-04-03 19:28:47 -0600 |
|---|---|---|
| committer | Paul Walmsley <pjw@kernel.org> | 2026-04-04 18:42:44 -0600 |
| commit | ae45f896a40a07449d9b45d0395fb7245fdd75fc (patch) | |
| tree | 87bdbd2000e54e683ac519e805f88480dc7b6623 /lib | |
| parent | d7df0505478a3e479e914f0554b6b774a07a1b88 (diff) | |
lib/string_kunit: add correctness test for strlen()
Add a KUnit test for strlen() to verify correctness across
different string lengths and memory alignments. Use vmalloc()
to place the NUL character at the page boundary to ensure
over-reads are detected.
Suggested-by: Kees Cook <kees@kernel.org>
Signed-off-by: Feng Jiang <jiangfeng@kylinos.cn>
Reviewed-by: Kees Cook <kees@kernel.org>
Link: https://patch.msgid.link/20260130025018.172925-2-jiangfeng@kylinos.cn
Signed-off-by: Paul Walmsley <pjw@kernel.org>
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/tests/string_kunit.c | 30 |
1 files changed, 30 insertions, 0 deletions
diff --git a/lib/tests/string_kunit.c b/lib/tests/string_kunit.c index f9a8e557ba77..26962118768e 100644 --- a/lib/tests/string_kunit.c +++ b/lib/tests/string_kunit.c @@ -6,10 +6,12 @@ #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #include <kunit/test.h> +#include <linux/mm.h> #include <linux/module.h> #include <linux/printk.h> #include <linux/slab.h> #include <linux/string.h> +#include <linux/vmalloc.h> #define STRCMP_LARGE_BUF_LEN 2048 #define STRCMP_CHANGE_POINT 1337 @@ -17,6 +19,9 @@ #define STRCMP_TEST_EXPECT_LOWER(test, fn, ...) KUNIT_EXPECT_LT(test, fn(__VA_ARGS__), 0) #define STRCMP_TEST_EXPECT_GREATER(test, fn, ...) KUNIT_EXPECT_GT(test, fn(__VA_ARGS__), 0) +#define STRING_TEST_MAX_LEN 128 +#define STRING_TEST_MAX_OFFSET 16 + static void string_test_memset16(struct kunit *test) { unsigned i, j, k; @@ -104,6 +109,30 @@ static void string_test_memset64(struct kunit *test) } } +static void string_test_strlen(struct kunit *test) +{ + size_t buf_size; + char *buf, *s; + + buf_size = PAGE_ALIGN(STRING_TEST_MAX_LEN + STRING_TEST_MAX_OFFSET + 1); + buf = vmalloc(buf_size); + KUNIT_ASSERT_NOT_ERR_OR_NULL(test, buf); + + memset(buf, 'A', buf_size); + + for (size_t offset = 0; offset < STRING_TEST_MAX_OFFSET; offset++) { + for (size_t len = 0; len <= STRING_TEST_MAX_LEN; len++) { + s = buf + buf_size - 1 - offset - len; + s[len] = '\0'; + KUNIT_EXPECT_EQ_MSG(test, strlen(s), len, + "offset:%zu len:%zu", offset, len); + s[len] = 'A'; + } + } + + vfree(buf); +} + static void string_test_strchr(struct kunit *test) { const char *test_string = "abcdefghijkl"; @@ -618,6 +647,7 @@ static struct kunit_case string_test_cases[] = { KUNIT_CASE(string_test_memset16), KUNIT_CASE(string_test_memset32), KUNIT_CASE(string_test_memset64), + KUNIT_CASE(string_test_strlen), KUNIT_CASE(string_test_strchr), KUNIT_CASE(string_test_strnchr), KUNIT_CASE(string_test_strspn), |