Re: [RESEND, PATCH v2] lib: overflow-test: add KUnit test of check_*_overflow functions
From: Kees Cook
Date: Thu Jun 18 2020 - 23:06:03 EST
On Thu, Jun 18, 2020 at 11:08:14AM -0300, Vitor Massaru Iha wrote:
> This adds the conversion of the runtime tests of check_*_overflow functions,
> from `lib/test_overflow.c`to KUnit tests.
>
> The log similar to the one seen in dmesg running test_overflow.c can be
> seen in `test.log`.
>
> Signed-off-by: Vitor Massaru Iha <vitor@xxxxxxxxxxx>
> Tested-by: David Gow <davidgow@xxxxxxxxxx>
> ---
> v2:
> * moved lib/test_overflow.c to lib/overflow-test.c;
I still don't want a dash in the filename, as this creates a difference
between the source name and the module name. While I still prefer
overflow_kunit.c, I can get over it and accept overflow_test.c :)
> * back to original license;
> * fixed style code;
> * keeps __initconst and added _refdata on overflow_test_cases variable;
> * keeps macros intact making asserts with the variable err;
> * removed duplicate test_s8_overflow();
> * fixed typos on commit message;
> ---
> lib/Kconfig.debug | 20 +++++++--
> lib/Makefile | 2 +-
> lib/{test_overflow.c => overflow-test.c} | 54 +++++++++---------------
> 3 files changed, 38 insertions(+), 38 deletions(-)
> rename lib/{test_overflow.c => overflow-test.c} (96%)
>
> diff --git a/lib/Kconfig.debug b/lib/Kconfig.debug
> index d74ac0fd6b2d..fb8a3955e969 100644
> --- a/lib/Kconfig.debug
> +++ b/lib/Kconfig.debug
> @@ -2000,9 +2000,6 @@ config TEST_UUID
> config TEST_XARRAY
> tristate "Test the XArray code at runtime"
>
> -config TEST_OVERFLOW
> - tristate "Test check_*_overflow() functions at runtime"
> -
> config TEST_RHASHTABLE
> tristate "Perform selftest on resizable hash table"
> help
> @@ -2155,6 +2152,23 @@ config SYSCTL_KUNIT_TEST
>
> If unsure, say N.
>
> +config OVERFLOW_KUNIT_TEST
> + tristate "KUnit test for overflow" if !KUNIT_ALL_TESTS
> + depends on KUNIT
> + default KUNIT_ALL_TESTS
> + help
> + This builds the overflow KUnit tests.
> +
> + KUnit tests run during boot and output the results to the debug log
> + in TAP format (http://testanything.org/). Only useful for kernel devs
> + running KUnit test harness and are not for inclusion into a production
> + build.
> +
> + For more information on KUnit and unit tests in general please refer
> + to the KUnit documentation in Documentation/dev-tools/kunit/.
> +
> + If unsure, say N.
> +
> config LIST_KUNIT_TEST
> tristate "KUnit Test for Kernel Linked-list structures" if !KUNIT_ALL_TESTS
> depends on KUNIT
> diff --git a/lib/Makefile b/lib/Makefile
> index b1c42c10073b..3b725c9f92d4 100644
> --- a/lib/Makefile
> +++ b/lib/Makefile
> @@ -75,7 +75,6 @@ obj-$(CONFIG_TEST_LIST_SORT) += test_list_sort.o
> obj-$(CONFIG_TEST_MIN_HEAP) += test_min_heap.o
> obj-$(CONFIG_TEST_LKM) += test_module.o
> obj-$(CONFIG_TEST_VMALLOC) += test_vmalloc.o
> -obj-$(CONFIG_TEST_OVERFLOW) += test_overflow.o
> obj-$(CONFIG_TEST_RHASHTABLE) += test_rhashtable.o
> obj-$(CONFIG_TEST_SORT) += test_sort.o
> obj-$(CONFIG_TEST_USER_COPY) += test_user_copy.o
> @@ -318,3 +317,4 @@ obj-$(CONFIG_OBJAGG) += objagg.o
> # KUnit tests
> obj-$(CONFIG_LIST_KUNIT_TEST) += list-test.o
> obj-$(CONFIG_LINEAR_RANGES_TEST) += test_linear_ranges.o
> +obj-$(CONFIG_OVERFLOW_KUNIT_TEST) += overflow-test.o
> diff --git a/lib/test_overflow.c b/lib/overflow-test.c
> similarity index 96%
> rename from lib/test_overflow.c
> rename to lib/overflow-test.c
> index 7a4b6f6c5473..d40ef06b1ade 100644
> --- a/lib/test_overflow.c
> +++ b/lib/overflow-test.c
> @@ -4,14 +4,11 @@
> */
> #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
>
> +#include <kunit/test.h>
> #include <linux/device.h>
> #include <linux/init.h>
> -#include <linux/kernel.h>
> #include <linux/mm.h>
> -#include <linux/module.h>
> #include <linux/overflow.h>
> -#include <linux/slab.h>
> -#include <linux/types.h>
> #include <linux/vmalloc.h>
>
> #define DEFINE_TEST_ARRAY(t) \
> @@ -270,7 +267,7 @@ DEFINE_TEST_FUNC(u64, "%llu");
> DEFINE_TEST_FUNC(s64, "%lld");
> #endif
>
> -static int __init test_overflow_calculation(void)
> +static void __init overflow_calculation_test(struct kunit *test)
> {
> int err = 0;
>
> @@ -285,10 +282,10 @@ static int __init test_overflow_calculation(void)
> err |= test_s64_overflow();
> #endif
>
> - return err;
> + KUNIT_EXPECT_FALSE(test, err);
> }
Ah! Well, yes, I guess that is one way to do it. :) I'm just curious:
why the change away from doing EXPECTs on individual tests?
>
> -static int __init test_overflow_shift(void)
> +static void __init overflow_shift_test(struct kunit *test)
> {
> int err = 0;
>
> @@ -479,7 +476,7 @@ static int __init test_overflow_shift(void)
> err |= TEST_ONE_SHIFT(0, 31, s32, 0, false);
> err |= TEST_ONE_SHIFT(0, 63, s64, 0, false);
>
> - return err;
> + KUNIT_EXPECT_FALSE(test, err);
> }
>
> /*
> @@ -555,7 +552,7 @@ DEFINE_TEST_ALLOC(kvzalloc_node, kvfree, 0, 1, 1);
> DEFINE_TEST_ALLOC(devm_kmalloc, devm_kfree, 1, 1, 0);
> DEFINE_TEST_ALLOC(devm_kzalloc, devm_kfree, 1, 1, 0);
>
> -static int __init test_overflow_allocation(void)
> +static void __init overflow_allocation_test(struct kunit *test)
> {
> const char device_name[] = "overflow-test";
> struct device *dev;
> @@ -563,10 +560,8 @@ static int __init test_overflow_allocation(void)
>
> /* Create dummy device for devm_kmalloc()-family tests. */
> dev = root_device_register(device_name);
> - if (IS_ERR(dev)) {
> - pr_warn("Cannot register test device\n");
> - return 1;
> - }
> + if (IS_ERR(dev))
> + kunit_warn(test, "Cannot register test device\n");
>
> err |= test_kmalloc(NULL);
> err |= test_kmalloc_node(NULL);
> @@ -585,30 +580,21 @@ static int __init test_overflow_allocation(void)
>
> device_unregister(dev);
>
> - return err;
> + KUNIT_EXPECT_FALSE(test, err);
> }
>
> -static int __init test_module_init(void)
> -{
> - int err = 0;
> -
> - err |= test_overflow_calculation();
> - err |= test_overflow_shift();
> - err |= test_overflow_allocation();
> -
> - if (err) {
> - pr_warn("FAIL!\n");
> - err = -EINVAL;
> - } else {
> - pr_info("all tests passed\n");
> - }
> +static struct kunit_case __refdata overflow_test_cases[] = {
Erm, __refdata? This seems like it should be __initdata.
> + KUNIT_CASE(overflow_calculation_test),
> + KUNIT_CASE(overflow_shift_test),
> + KUNIT_CASE(overflow_allocation_test),
> + {}
> +};
>
> - return err;
> -}
> +static struct kunit_suite overflow_test_suite = {
And this.
> + .name = "overflow",
> + .test_cases = overflow_test_cases,
> +};
>
> -static void __exit test_module_exit(void)
> -{ }
> +kunit_test_suites(&overflow_test_suite);
I suspect the problem causing the need for __refdata there is the lack
of __init markings on the functions in kunit_test_suites()?
(Or maybe this is explained somewhere else I've missed it.)
For example, would this work? (I haven't tested it all.)
diff --git a/include/kunit/test.h b/include/kunit/test.h
index 59f3144f009a..aad746d59d2f 100644
--- a/include/kunit/test.h
+++ b/include/kunit/test.h
@@ -233,9 +233,9 @@ size_t kunit_suite_num_test_cases(struct kunit_suite *suite);
unsigned int kunit_test_case_num(struct kunit_suite *suite,
struct kunit_case *test_case);
-int __kunit_test_suites_init(struct kunit_suite **suites);
+int __init __kunit_test_suites_init(struct kunit_suite **suites);
-void __kunit_test_suites_exit(struct kunit_suite **suites);
+void __exit __kunit_test_suites_exit(struct kunit_suite **suites);
/**
* kunit_test_suites() - used to register one or more &struct kunit_suite
@@ -263,8 +263,9 @@ void __kunit_test_suites_exit(struct kunit_suite **suites);
* everything else is definitely initialized.
*/
#define kunit_test_suites(suites_list...) \
- static struct kunit_suite *suites[] = {suites_list, NULL}; \
- static int kunit_test_suites_init(void) \
+ static struct kunit_suite *suites[] __initdata = \
+ {suites_list, NULL}; \
+ static int __init kunit_test_suites_init(void) \
{ \
return __kunit_test_suites_init(suites); \
} \
diff --git a/lib/kunit/test.c b/lib/kunit/test.c
index c36037200310..bfb0f563721b 100644
--- a/lib/kunit/test.c
+++ b/lib/kunit/test.c
@@ -381,7 +381,7 @@ static void kunit_init_suite(struct kunit_suite *suite)
kunit_debugfs_create_suite(suite);
}
-int __kunit_test_suites_init(struct kunit_suite **suites)
+int __init __kunit_test_suites_init(struct kunit_suite **suites)
{
unsigned int i;
@@ -393,7 +393,7 @@ int __kunit_test_suites_init(struct kunit_suite **suites)
}
EXPORT_SYMBOL_GPL(__kunit_test_suites_init);
-static void kunit_exit_suite(struct kunit_suite *suite)
+static void __exit kunit_exit_suite(struct kunit_suite *suite)
{
kunit_debugfs_destroy_suite(suite);
}
>
> -module_init(test_module_init);
> -module_exit(test_module_exit);
> MODULE_LICENSE("Dual MIT/GPL");
>
> base-commit: 7bf200b3a4ac10b1b0376c70b8c66ed39eae7cdd
> prerequisite-patch-id: e827b6b22f950b9f69620805a04e4a264cf4cc6a
> --
> 2.26.2
>
Thanks again for the conversion!
--
Kees Cook