[PATCH 2/5] string: Merge strscpy KUnit tests into string_kunit.c
From: Kees Cook
Date: Fri Apr 19 2024 - 10:03:24 EST
Move the strscpy() tests into string_kunit.c. Remove the separate
Kconfig and Makefile rule.
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
---
Cc: Andy Shevchenko <andy@xxxxxxxxxx>
Cc: Ivan Orlov <ivan.orlov0322@xxxxxxxxx>
Cc: linux-hardening@xxxxxxxxxxxxxxx
---
MAINTAINERS | 1 -
lib/Kconfig.debug | 5 --
lib/Makefile | 1 -
lib/string_kunit.c | 120 +++++++++++++++++++++++++++++++++++++
lib/strscpy_kunit.c | 143 --------------------------------------------
5 files changed, 120 insertions(+), 150 deletions(-)
delete mode 100644 lib/strscpy_kunit.c
diff --git a/MAINTAINERS b/MAINTAINERS
index 7c121493f43d..17d079aa15ec 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -8442,7 +8442,6 @@ F: include/linux/fortify-string.h
F: lib/fortify_kunit.c
F: lib/memcpy_kunit.c
F: lib/strcat_kunit.c
-F: lib/strscpy_kunit.c
F: lib/test_fortify/*
F: scripts/test_fortify.sh
K: \b__NO_FORTIFY\b
diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
index c63a5fbf1f1c..7ffb06eabcd1 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -2763,11 +2763,6 @@ config STRCAT_KUNIT_TEST
depends on KUNIT
default KUNIT_ALL_TESTS
-config STRSCPY_KUNIT_TEST
- tristate "Test strscpy*() family of functions at runtime" if !KUNIT_ALL_TESTS
- depends on KUNIT
- default KUNIT_ALL_TESTS
-
config SIPHASH_KUNIT_TEST
tristate "Perform selftest on siphash functions" if !KUNIT_ALL_TESTS
depends on KUNIT
diff --git a/lib/Makefile b/lib/Makefile
index ffc6b2341b45..5f994b963d1a 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -404,7 +404,6 @@ CFLAGS_fortify_kunit.o += $(call cc-disable-warning, stringop-truncation)
CFLAGS_fortify_kunit.o += $(DISABLE_STRUCTLEAK_PLUGIN)
obj-$(CONFIG_FORTIFY_KUNIT_TEST) += fortify_kunit.o
obj-$(CONFIG_STRCAT_KUNIT_TEST) += strcat_kunit.o
-obj-$(CONFIG_STRSCPY_KUNIT_TEST) += strscpy_kunit.o
obj-$(CONFIG_SIPHASH_KUNIT_TEST) += siphash_kunit.o
obj-$(CONFIG_GENERIC_LIB_DEVMEM_IS_ALLOWED) += devmem_is_allowed.o
diff --git a/lib/string_kunit.c b/lib/string_kunit.c
index dd19bd7748aa..4af04643f4c2 100644
--- a/lib/string_kunit.c
+++ b/lib/string_kunit.c
@@ -326,6 +326,125 @@ static void test_strncasecmp_long_strings(struct kunit *test)
strcmp_buffer2, STRCMP_CHANGE_POINT + 1);
}
+/**
+ * strscpy_check() - Run a specific test case.
+ * @test: KUnit test context pointer
+ * @src: Source string, argument to strscpy_pad()
+ * @count: Size of destination buffer, argument to strscpy_pad()
+ * @expected: Expected return value from call to strscpy_pad()
+ * @chars: Number of characters from the src string expected to be
+ * written to the dst buffer.
+ * @terminator: 1 if there should be a terminating null byte 0 otherwise.
+ * @pad: Number of pad characters expected (in the tail of dst buffer).
+ * (@pad does not include the null terminator byte.)
+ *
+ * Calls strscpy_pad() and verifies the return value and state of the
+ * destination buffer after the call returns.
+ */
+static void strscpy_check(struct kunit *test, char *src, int count,
+ int expected, int chars, int terminator, int pad)
+{
+ int nr_bytes_poison;
+ int max_expected;
+ int max_count;
+ int written;
+ char buf[6];
+ int index, i;
+ const char POISON = 'z';
+
+ KUNIT_ASSERT_TRUE_MSG(test, src != NULL,
+ "null source string not supported");
+
+ memset(buf, POISON, sizeof(buf));
+ /* Future proofing test suite, validate args */
+ max_count = sizeof(buf) - 2; /* Space for null and to verify overflow */
+ max_expected = count - 1; /* Space for the null */
+
+ KUNIT_ASSERT_LE_MSG(test, count, max_count,
+ "count (%d) is too big (%d) ... aborting", count, max_count);
+ KUNIT_EXPECT_LE_MSG(test, expected, max_expected,
+ "expected (%d) is bigger than can possibly be returned (%d)",
+ expected, max_expected);
+
+ written = strscpy_pad(buf, src, count);
+ KUNIT_ASSERT_EQ(test, written, expected);
+
+ if (count && written == -E2BIG) {
+ KUNIT_ASSERT_EQ_MSG(test, 0, strncmp(buf, src, count - 1),
+ "buffer state invalid for -E2BIG");
+ KUNIT_ASSERT_EQ_MSG(test, buf[count - 1], '\0',
+ "too big string is not null terminated correctly");
+ }
+
+ for (i = 0; i < chars; i++)
+ KUNIT_ASSERT_EQ_MSG(test, buf[i], src[i],
+ "buf[i]==%c != src[i]==%c", buf[i], src[i]);
+
+ if (terminator)
+ KUNIT_ASSERT_EQ_MSG(test, buf[count - 1], '\0',
+ "string is not null terminated correctly");
+
+ for (i = 0; i < pad; i++) {
+ index = chars + terminator + i;
+ KUNIT_ASSERT_EQ_MSG(test, buf[index], '\0',
+ "padding missing at index: %d", i);
+ }
+
+ nr_bytes_poison = sizeof(buf) - chars - terminator - pad;
+ for (i = 0; i < nr_bytes_poison; i++) {
+ index = sizeof(buf) - 1 - i; /* Check from the end back */
+ KUNIT_ASSERT_EQ_MSG(test, buf[index], POISON,
+ "poison value missing at index: %d", i);
+ }
+}
+
+static void test_strscpy(struct kunit *test)
+{
+ char dest[8];
+
+ /*
+ * strscpy_check() uses a destination buffer of size 6 and needs at
+ * least 2 characters spare (one for null and one to check for
+ * overflow). This means we should only call tc() with
+ * strings up to a maximum of 4 characters long and 'count'
+ * should not exceed 4. To test with longer strings increase
+ * the buffer size in tc().
+ */
+
+ /* strscpy_check(test, src, count, expected, chars, terminator, pad) */
+ strscpy_check(test, "a", 0, -E2BIG, 0, 0, 0);
+ strscpy_check(test, "", 0, -E2BIG, 0, 0, 0);
+
+ strscpy_check(test, "a", 1, -E2BIG, 0, 1, 0);
+ strscpy_check(test, "", 1, 0, 0, 1, 0);
+
+ strscpy_check(test, "ab", 2, -E2BIG, 1, 1, 0);
+ strscpy_check(test, "a", 2, 1, 1, 1, 0);
+ strscpy_check(test, "", 2, 0, 0, 1, 1);
+
+ strscpy_check(test, "abc", 3, -E2BIG, 2, 1, 0);
+ strscpy_check(test, "ab", 3, 2, 2, 1, 0);
+ strscpy_check(test, "a", 3, 1, 1, 1, 1);
+ strscpy_check(test, "", 3, 0, 0, 1, 2);
+
+ strscpy_check(test, "abcd", 4, -E2BIG, 3, 1, 0);
+ strscpy_check(test, "abc", 4, 3, 3, 1, 0);
+ strscpy_check(test, "ab", 4, 2, 2, 1, 1);
+ strscpy_check(test, "a", 4, 1, 1, 1, 2);
+ strscpy_check(test, "", 4, 0, 0, 1, 3);
+
+ /* Compile-time-known source strings. */
+ KUNIT_EXPECT_EQ(test, strscpy(dest, "", ARRAY_SIZE(dest)), 0);
+ KUNIT_EXPECT_EQ(test, strscpy(dest, "", 3), 0);
+ KUNIT_EXPECT_EQ(test, strscpy(dest, "", 1), 0);
+ KUNIT_EXPECT_EQ(test, strscpy(dest, "", 0), -E2BIG);
+ KUNIT_EXPECT_EQ(test, strscpy(dest, "Fixed", ARRAY_SIZE(dest)), 5);
+ KUNIT_EXPECT_EQ(test, strscpy(dest, "Fixed", 3), -E2BIG);
+ KUNIT_EXPECT_EQ(test, strscpy(dest, "Fixed", 1), -E2BIG);
+ KUNIT_EXPECT_EQ(test, strscpy(dest, "Fixed", 0), -E2BIG);
+ KUNIT_EXPECT_EQ(test, strscpy(dest, "This is too long", ARRAY_SIZE(dest)), -E2BIG);
+}
+
static struct kunit_case string_test_cases[] = {
KUNIT_CASE(test_memset16),
KUNIT_CASE(test_memset32),
@@ -341,6 +460,7 @@ static struct kunit_case string_test_cases[] = {
KUNIT_CASE(test_strcasecmp_long_strings),
KUNIT_CASE(test_strncasecmp),
KUNIT_CASE(test_strncasecmp_long_strings),
+ KUNIT_CASE(test_strscpy),
{}
};
diff --git a/lib/strscpy_kunit.c b/lib/strscpy_kunit.c
deleted file mode 100644
index b6d1d93a8883..000000000000
--- a/lib/strscpy_kunit.c
+++ /dev/null
@@ -1,143 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0+
-/*
- * Kernel module for testing 'strscpy' family of functions.
- */
-
-#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
-
-#include <kunit/test.h>
-#include <linux/string.h>
-
-/**
- * strscpy_check() - Run a specific test case.
- * @test: KUnit test context pointer
- * @src: Source string, argument to strscpy_pad()
- * @count: Size of destination buffer, argument to strscpy_pad()
- * @expected: Expected return value from call to strscpy_pad()
- * @chars: Number of characters from the src string expected to be
- * written to the dst buffer.
- * @terminator: 1 if there should be a terminating null byte 0 otherwise.
- * @pad: Number of pad characters expected (in the tail of dst buffer).
- * (@pad does not include the null terminator byte.)
- *
- * Calls strscpy_pad() and verifies the return value and state of the
- * destination buffer after the call returns.
- */
-static void strscpy_check(struct kunit *test, char *src, int count,
- int expected, int chars, int terminator, int pad)
-{
- int nr_bytes_poison;
- int max_expected;
- int max_count;
- int written;
- char buf[6];
- int index, i;
- const char POISON = 'z';
-
- KUNIT_ASSERT_TRUE_MSG(test, src != NULL,
- "null source string not supported");
-
- memset(buf, POISON, sizeof(buf));
- /* Future proofing test suite, validate args */
- max_count = sizeof(buf) - 2; /* Space for null and to verify overflow */
- max_expected = count - 1; /* Space for the null */
-
- KUNIT_ASSERT_LE_MSG(test, count, max_count,
- "count (%d) is too big (%d) ... aborting", count, max_count);
- KUNIT_EXPECT_LE_MSG(test, expected, max_expected,
- "expected (%d) is bigger than can possibly be returned (%d)",
- expected, max_expected);
-
- written = strscpy_pad(buf, src, count);
- KUNIT_ASSERT_EQ(test, written, expected);
-
- if (count && written == -E2BIG) {
- KUNIT_ASSERT_EQ_MSG(test, 0, strncmp(buf, src, count - 1),
- "buffer state invalid for -E2BIG");
- KUNIT_ASSERT_EQ_MSG(test, buf[count - 1], '\0',
- "too big string is not null terminated correctly");
- }
-
- for (i = 0; i < chars; i++)
- KUNIT_ASSERT_EQ_MSG(test, buf[i], src[i],
- "buf[i]==%c != src[i]==%c", buf[i], src[i]);
-
- if (terminator)
- KUNIT_ASSERT_EQ_MSG(test, buf[count - 1], '\0',
- "string is not null terminated correctly");
-
- for (i = 0; i < pad; i++) {
- index = chars + terminator + i;
- KUNIT_ASSERT_EQ_MSG(test, buf[index], '\0',
- "padding missing at index: %d", i);
- }
-
- nr_bytes_poison = sizeof(buf) - chars - terminator - pad;
- for (i = 0; i < nr_bytes_poison; i++) {
- index = sizeof(buf) - 1 - i; /* Check from the end back */
- KUNIT_ASSERT_EQ_MSG(test, buf[index], POISON,
- "poison value missing at index: %d", i);
- }
-}
-
-static void test_strscpy(struct kunit *test)
-{
- char dest[8];
-
- /*
- * strscpy_check() uses a destination buffer of size 6 and needs at
- * least 2 characters spare (one for null and one to check for
- * overflow). This means we should only call tc() with
- * strings up to a maximum of 4 characters long and 'count'
- * should not exceed 4. To test with longer strings increase
- * the buffer size in tc().
- */
-
- /* strscpy_check(test, src, count, expected, chars, terminator, pad) */
- strscpy_check(test, "a", 0, -E2BIG, 0, 0, 0);
- strscpy_check(test, "", 0, -E2BIG, 0, 0, 0);
-
- strscpy_check(test, "a", 1, -E2BIG, 0, 1, 0);
- strscpy_check(test, "", 1, 0, 0, 1, 0);
-
- strscpy_check(test, "ab", 2, -E2BIG, 1, 1, 0);
- strscpy_check(test, "a", 2, 1, 1, 1, 0);
- strscpy_check(test, "", 2, 0, 0, 1, 1);
-
- strscpy_check(test, "abc", 3, -E2BIG, 2, 1, 0);
- strscpy_check(test, "ab", 3, 2, 2, 1, 0);
- strscpy_check(test, "a", 3, 1, 1, 1, 1);
- strscpy_check(test, "", 3, 0, 0, 1, 2);
-
- strscpy_check(test, "abcd", 4, -E2BIG, 3, 1, 0);
- strscpy_check(test, "abc", 4, 3, 3, 1, 0);
- strscpy_check(test, "ab", 4, 2, 2, 1, 1);
- strscpy_check(test, "a", 4, 1, 1, 1, 2);
- strscpy_check(test, "", 4, 0, 0, 1, 3);
-
- /* Compile-time-known source strings. */
- KUNIT_EXPECT_EQ(test, strscpy(dest, "", ARRAY_SIZE(dest)), 0);
- KUNIT_EXPECT_EQ(test, strscpy(dest, "", 3), 0);
- KUNIT_EXPECT_EQ(test, strscpy(dest, "", 1), 0);
- KUNIT_EXPECT_EQ(test, strscpy(dest, "", 0), -E2BIG);
- KUNIT_EXPECT_EQ(test, strscpy(dest, "Fixed", ARRAY_SIZE(dest)), 5);
- KUNIT_EXPECT_EQ(test, strscpy(dest, "Fixed", 3), -E2BIG);
- KUNIT_EXPECT_EQ(test, strscpy(dest, "Fixed", 1), -E2BIG);
- KUNIT_EXPECT_EQ(test, strscpy(dest, "Fixed", 0), -E2BIG);
- KUNIT_EXPECT_EQ(test, strscpy(dest, "This is too long", ARRAY_SIZE(dest)), -E2BIG);
-}
-
-static struct kunit_case strscpy_test_cases[] = {
- KUNIT_CASE(test_strscpy),
- {}
-};
-
-static struct kunit_suite strscpy_test_suite = {
- .name = "strscpy",
- .test_cases = strscpy_test_cases,
-};
-
-kunit_test_suite(strscpy_test_suite);
-
-MODULE_AUTHOR("Tobin C. Harding <tobin@xxxxxxxxxx>");
-MODULE_LICENSE("GPL");
--
2.34.1