[PATCH v3 03/16] lib: overflow: Report test failures

From: Kees Cook
Date: Thu May 31 2018 - 20:44:07 EST


This adjusts the overflow test to report failures, and prepares to
add allocation tests.

Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
---
lib/test_overflow.c | 75 ++++++++++++++++++++++++++++++++-------------
1 file changed, 54 insertions(+), 21 deletions(-)

diff --git a/lib/test_overflow.c b/lib/test_overflow.c
index e1e45ba17ff0..482d71c880fa 100644
--- a/lib/test_overflow.c
+++ b/lib/test_overflow.c
@@ -212,42 +212,59 @@ DEFINE_TEST_ARRAY(s64) = {
};

#define DEFINE_TEST_FUNC(t, fmt) \
-static void __init do_test_ ## t(const struct test_ ## t *p) \
+static int __init do_test_ ## t(const struct test_ ## t *p) \
{ \
t r; \
+ int err = 0; \
bool of; \
\
of = check_add_overflow(p->a, p->b, &r); \
- if (of != p->s_of) \
+ if (of != p->s_of) { \
pr_warn("expected "fmt" + "fmt" to%s overflow (type %s)\n", \
p->a, p->b, p->s_of ? "" : " not", #t); \
- if (r != p->sum) \
+ err = 1; \
+ } \
+ if (r != p->sum) { \
pr_warn("expected "fmt" + "fmt" == "fmt", got "fmt" (type %s)\n", \
p->a, p->b, p->sum, r, #t); \
+ err = 1; \
+ } \
\
of = check_sub_overflow(p->a, p->b, &r); \
- if (of != p->d_of) \
+ if (of != p->d_of) { \
pr_warn("expected "fmt" - "fmt" to%s overflow (type %s)\n", \
p->a, p->b, p->s_of ? "" : " not", #t); \
- if (r != p->diff) \
+ err = 1; \
+ } \
+ if (r != p->diff) { \
pr_warn("expected "fmt" - "fmt" == "fmt", got "fmt" (type %s)\n", \
p->a, p->b, p->diff, r, #t); \
+ err = 1; \
+ } \
\
of = check_mul_overflow(p->a, p->b, &r); \
- if (of != p->p_of) \
+ if (of != p->p_of) { \
pr_warn("expected "fmt" * "fmt" to%s overflow (type %s)\n", \
p->a, p->b, p->p_of ? "" : " not", #t); \
- if (r != p->prod) \
+ err = 1; \
+ } \
+ if (r != p->prod) { \
pr_warn("expected "fmt" * "fmt" == "fmt", got "fmt" (type %s)\n", \
p->a, p->b, p->prod, r, #t); \
+ err = 1; \
+ } \
+ \
+ return err; \
} \
\
-static void __init test_ ## t ## _overflow(void) { \
+static int __init test_ ## t ## _overflow(void) { \
unsigned i; \
+ int err = 0; \
\
pr_info("%-3s: %zu tests\n", #t, ARRAY_SIZE(t ## _tests)); \
for (i = 0; i < ARRAY_SIZE(t ## _tests); ++i) \
- do_test_ ## t(&t ## _tests[i]); \
+ err |= do_test_ ## t(&t ## _tests[i]); \
+ return err; \
}

DEFINE_TEST_FUNC(u8, "%d");
@@ -260,26 +277,42 @@ DEFINE_TEST_FUNC(s16, "%d");
DEFINE_TEST_FUNC(s32, "%d");
DEFINE_TEST_FUNC(s64, "%lld");

-static int __init test_overflow(void)
+static int __init test_overflow_calculation(void)
+{
+ int err = 0;
+
+ err |= test_u8_overflow();
+ err |= test_u16_overflow();
+ err |= test_u32_overflow();
+ err |= test_u64_overflow();
+
+ err |= test_s8_overflow();
+ err |= test_s16_overflow();
+ err |= test_s32_overflow();
+ err |= test_s64_overflow();
+
+ return err;
+}
+
+static int __init test_module_init(void)
{
- test_u8_overflow();
- test_u16_overflow();
- test_u32_overflow();
- test_u64_overflow();
+ int err = 0;

- test_s8_overflow();
- test_s16_overflow();
- test_s32_overflow();
- test_s64_overflow();
+ err |= test_overflow_calculation();

- pr_info("done\n");
+ if (err) {
+ pr_warn("FAIL!\n");
+ err = -EINVAL;
+ } else {
+ pr_info("all tests passed\n");
+ }

- return 0;
+ return err;
}

static void __exit test_module_exit(void)
{ }

-module_init(test_overflow);
+module_init(test_module_init);
module_exit(test_module_exit);
MODULE_LICENSE("Dual MIT/GPL");
--
2.17.0