[PATCH 4/5] string: Merge strcat KUnit tests into string_kunit.c

From: Kees Cook
Date: Fri Apr 19 2024 - 10:03:14 EST


Move the strcat() 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/strcat_kunit.c | 104 ---------------------------------------------
lib/string_kunit.c | 82 +++++++++++++++++++++++++++++++++++
5 files changed, 82 insertions(+), 111 deletions(-)
delete mode 100644 lib/strcat_kunit.c

diff --git a/MAINTAINERS b/MAINTAINERS
index 17d079aa15ec..8974511315c3 100644
--- a/MAINTAINERS
+++ b/MAINTAINERS
@@ -8441,7 +8441,6 @@ T: git git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux.git for-next/har
F: include/linux/fortify-string.h
F: lib/fortify_kunit.c
F: lib/memcpy_kunit.c
-F: lib/strcat_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 7ffb06eabcd1..a384070c74bc 100644
--- a/lib/Kconfig.debug
+++ b/lib/Kconfig.debug
@@ -2758,11 +2758,6 @@ config HW_BREAKPOINT_KUNIT_TEST

If unsure, say N.

-config STRCAT_KUNIT_TEST
- tristate "Test strcat() 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 5f994b963d1a..b040ad5f8022 100644
--- a/lib/Makefile
+++ b/lib/Makefile
@@ -403,7 +403,6 @@ CFLAGS_fortify_kunit.o += $(call cc-disable-warning, stringop-overread)
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_SIPHASH_KUNIT_TEST) += siphash_kunit.o

obj-$(CONFIG_GENERIC_LIB_DEVMEM_IS_ALLOWED) += devmem_is_allowed.o
diff --git a/lib/strcat_kunit.c b/lib/strcat_kunit.c
deleted file mode 100644
index ca09f7f0e6a2..000000000000
--- a/lib/strcat_kunit.c
+++ /dev/null
@@ -1,104 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * Kernel module for testing 'strcat' family of functions.
- */
-
-#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
-
-#include <kunit/test.h>
-#include <linux/string.h>
-
-static volatile int unconst;
-
-static void test_strcat(struct kunit *test)
-{
- char dest[8];
-
- /* Destination is terminated. */
- memset(dest, 0, sizeof(dest));
- KUNIT_EXPECT_EQ(test, strlen(dest), 0);
- /* Empty copy does nothing. */
- KUNIT_EXPECT_TRUE(test, strcat(dest, "") == dest);
- KUNIT_EXPECT_STREQ(test, dest, "");
- /* 4 characters copied in, stops at %NUL. */
- KUNIT_EXPECT_TRUE(test, strcat(dest, "four\000123") == dest);
- KUNIT_EXPECT_STREQ(test, dest, "four");
- KUNIT_EXPECT_EQ(test, dest[5], '\0');
- /* 2 more characters copied in okay. */
- KUNIT_EXPECT_TRUE(test, strcat(dest, "AB") == dest);
- KUNIT_EXPECT_STREQ(test, dest, "fourAB");
-}
-
-static void test_strncat(struct kunit *test)
-{
- char dest[8];
-
- /* Destination is terminated. */
- memset(dest, 0, sizeof(dest));
- KUNIT_EXPECT_EQ(test, strlen(dest), 0);
- /* Empty copy of size 0 does nothing. */
- KUNIT_EXPECT_TRUE(test, strncat(dest, "", 0 + unconst) == dest);
- KUNIT_EXPECT_STREQ(test, dest, "");
- /* Empty copy of size 1 does nothing too. */
- KUNIT_EXPECT_TRUE(test, strncat(dest, "", 1 + unconst) == dest);
- KUNIT_EXPECT_STREQ(test, dest, "");
- /* Copy of max 0 characters should do nothing. */
- KUNIT_EXPECT_TRUE(test, strncat(dest, "asdf", 0 + unconst) == dest);
- KUNIT_EXPECT_STREQ(test, dest, "");
-
- /* 4 characters copied in, even if max is 8. */
- KUNIT_EXPECT_TRUE(test, strncat(dest, "four\000123", 8 + unconst) == dest);
- KUNIT_EXPECT_STREQ(test, dest, "four");
- KUNIT_EXPECT_EQ(test, dest[5], '\0');
- KUNIT_EXPECT_EQ(test, dest[6], '\0');
- /* 2 characters copied in okay, 2 ignored. */
- KUNIT_EXPECT_TRUE(test, strncat(dest, "ABCD", 2 + unconst) == dest);
- KUNIT_EXPECT_STREQ(test, dest, "fourAB");
-}
-
-static void test_strlcat(struct kunit *test)
-{
- char dest[8] = "";
- int len = sizeof(dest) + unconst;
-
- /* Destination is terminated. */
- KUNIT_EXPECT_EQ(test, strlen(dest), 0);
- /* Empty copy is size 0. */
- KUNIT_EXPECT_EQ(test, strlcat(dest, "", len), 0);
- KUNIT_EXPECT_STREQ(test, dest, "");
- /* Size 1 should keep buffer terminated, report size of source only. */
- KUNIT_EXPECT_EQ(test, strlcat(dest, "four", 1 + unconst), 4);
- KUNIT_EXPECT_STREQ(test, dest, "");
-
- /* 4 characters copied in. */
- KUNIT_EXPECT_EQ(test, strlcat(dest, "four", len), 4);
- KUNIT_EXPECT_STREQ(test, dest, "four");
- /* 2 characters copied in okay, gets to 6 total. */
- KUNIT_EXPECT_EQ(test, strlcat(dest, "AB", len), 6);
- KUNIT_EXPECT_STREQ(test, dest, "fourAB");
- /* 2 characters ignored if max size (7) reached. */
- KUNIT_EXPECT_EQ(test, strlcat(dest, "CD", 7 + unconst), 8);
- KUNIT_EXPECT_STREQ(test, dest, "fourAB");
- /* 1 of 2 characters skipped, now at true max size. */
- KUNIT_EXPECT_EQ(test, strlcat(dest, "EFG", len), 9);
- KUNIT_EXPECT_STREQ(test, dest, "fourABE");
- /* Everything else ignored, now at full size. */
- KUNIT_EXPECT_EQ(test, strlcat(dest, "1234", len), 11);
- KUNIT_EXPECT_STREQ(test, dest, "fourABE");
-}
-
-static struct kunit_case strcat_test_cases[] = {
- KUNIT_CASE(test_strcat),
- KUNIT_CASE(test_strncat),
- KUNIT_CASE(test_strlcat),
- {}
-};
-
-static struct kunit_suite strcat_test_suite = {
- .name = "strcat",
- .test_cases = strcat_test_cases,
-};
-
-kunit_test_suite(strcat_test_suite);
-
-MODULE_LICENSE("GPL");
diff --git a/lib/string_kunit.c b/lib/string_kunit.c
index 4af04643f4c2..48752ed19d56 100644
--- a/lib/string_kunit.c
+++ b/lib/string_kunit.c
@@ -445,6 +445,85 @@ static void test_strscpy(struct kunit *test)
KUNIT_EXPECT_EQ(test, strscpy(dest, "This is too long", ARRAY_SIZE(dest)), -E2BIG);
}

+static volatile int unconst;
+
+static void test_strcat(struct kunit *test)
+{
+ char dest[8];
+
+ /* Destination is terminated. */
+ memset(dest, 0, sizeof(dest));
+ KUNIT_EXPECT_EQ(test, strlen(dest), 0);
+ /* Empty copy does nothing. */
+ KUNIT_EXPECT_TRUE(test, strcat(dest, "") == dest);
+ KUNIT_EXPECT_STREQ(test, dest, "");
+ /* 4 characters copied in, stops at %NUL. */
+ KUNIT_EXPECT_TRUE(test, strcat(dest, "four\000123") == dest);
+ KUNIT_EXPECT_STREQ(test, dest, "four");
+ KUNIT_EXPECT_EQ(test, dest[5], '\0');
+ /* 2 more characters copied in okay. */
+ KUNIT_EXPECT_TRUE(test, strcat(dest, "AB") == dest);
+ KUNIT_EXPECT_STREQ(test, dest, "fourAB");
+}
+
+static void test_strncat(struct kunit *test)
+{
+ char dest[8];
+
+ /* Destination is terminated. */
+ memset(dest, 0, sizeof(dest));
+ KUNIT_EXPECT_EQ(test, strlen(dest), 0);
+ /* Empty copy of size 0 does nothing. */
+ KUNIT_EXPECT_TRUE(test, strncat(dest, "", 0 + unconst) == dest);
+ KUNIT_EXPECT_STREQ(test, dest, "");
+ /* Empty copy of size 1 does nothing too. */
+ KUNIT_EXPECT_TRUE(test, strncat(dest, "", 1 + unconst) == dest);
+ KUNIT_EXPECT_STREQ(test, dest, "");
+ /* Copy of max 0 characters should do nothing. */
+ KUNIT_EXPECT_TRUE(test, strncat(dest, "asdf", 0 + unconst) == dest);
+ KUNIT_EXPECT_STREQ(test, dest, "");
+
+ /* 4 characters copied in, even if max is 8. */
+ KUNIT_EXPECT_TRUE(test, strncat(dest, "four\000123", 8 + unconst) == dest);
+ KUNIT_EXPECT_STREQ(test, dest, "four");
+ KUNIT_EXPECT_EQ(test, dest[5], '\0');
+ KUNIT_EXPECT_EQ(test, dest[6], '\0');
+ /* 2 characters copied in okay, 2 ignored. */
+ KUNIT_EXPECT_TRUE(test, strncat(dest, "ABCD", 2 + unconst) == dest);
+ KUNIT_EXPECT_STREQ(test, dest, "fourAB");
+}
+
+static void test_strlcat(struct kunit *test)
+{
+ char dest[8] = "";
+ int len = sizeof(dest) + unconst;
+
+ /* Destination is terminated. */
+ KUNIT_EXPECT_EQ(test, strlen(dest), 0);
+ /* Empty copy is size 0. */
+ KUNIT_EXPECT_EQ(test, strlcat(dest, "", len), 0);
+ KUNIT_EXPECT_STREQ(test, dest, "");
+ /* Size 1 should keep buffer terminated, report size of source only. */
+ KUNIT_EXPECT_EQ(test, strlcat(dest, "four", 1 + unconst), 4);
+ KUNIT_EXPECT_STREQ(test, dest, "");
+
+ /* 4 characters copied in. */
+ KUNIT_EXPECT_EQ(test, strlcat(dest, "four", len), 4);
+ KUNIT_EXPECT_STREQ(test, dest, "four");
+ /* 2 characters copied in okay, gets to 6 total. */
+ KUNIT_EXPECT_EQ(test, strlcat(dest, "AB", len), 6);
+ KUNIT_EXPECT_STREQ(test, dest, "fourAB");
+ /* 2 characters ignored if max size (7) reached. */
+ KUNIT_EXPECT_EQ(test, strlcat(dest, "CD", 7 + unconst), 8);
+ KUNIT_EXPECT_STREQ(test, dest, "fourAB");
+ /* 1 of 2 characters skipped, now at true max size. */
+ KUNIT_EXPECT_EQ(test, strlcat(dest, "EFG", len), 9);
+ KUNIT_EXPECT_STREQ(test, dest, "fourABE");
+ /* Everything else ignored, now at full size. */
+ KUNIT_EXPECT_EQ(test, strlcat(dest, "1234", len), 11);
+ KUNIT_EXPECT_STREQ(test, dest, "fourABE");
+}
+
static struct kunit_case string_test_cases[] = {
KUNIT_CASE(test_memset16),
KUNIT_CASE(test_memset32),
@@ -461,6 +540,9 @@ static struct kunit_case string_test_cases[] = {
KUNIT_CASE(test_strncasecmp),
KUNIT_CASE(test_strncasecmp_long_strings),
KUNIT_CASE(test_strscpy),
+ KUNIT_CASE(test_strcat),
+ KUNIT_CASE(test_strncat),
+ KUNIT_CASE(test_strlcat),
{}
};

--
2.34.1