Re: [PATCH] overflow: Refactor test skips for Clang-specific issues
From: Gwan-gyeong Mun
Date: Mon Oct 10 2022 - 10:41:23 EST
Thanks for updating it.
Looks good to me.
Reviewed-by: Gwan-gyeong Mun <gwan-gyeong.mun@xxxxxxxxx>
On 10/7/22 2:00 AM, Kees Cook wrote:
Convert test exclusion into test skipping. This brings the logic for
why a test is being skipped into the test itself, instead of having to
spread ifdefs around the code. This will make cleanup easier as minimum
tests get raised. Drop __maybe_unused so missed tests will be noticed
again and clean up whitespace.
For example, clang-11 on i386:
[15:52:32] ================== overflow (18 subtests) ==================
[15:52:32] [PASSED] u8_u8__u8_overflow_test
[15:52:32] [PASSED] s8_s8__s8_overflow_test
[15:52:32] [PASSED] u16_u16__u16_overflow_test
[15:52:32] [PASSED] s16_s16__s16_overflow_test
[15:52:32] [PASSED] u32_u32__u32_overflow_test
[15:52:32] [PASSED] s32_s32__s32_overflow_test
[15:52:32] [SKIPPED] u64_u64__u64_overflow_test
[15:52:32] [SKIPPED] s64_s64__s64_overflow_test
[15:52:32] [SKIPPED] u32_u32__int_overflow_test
[15:52:32] [PASSED] u32_u32__u8_overflow_test
[15:52:32] [PASSED] u8_u8__int_overflow_test
[15:52:32] [PASSED] int_int__u8_overflow_test
[15:52:32] [PASSED] shift_sane_test
[15:52:32] [PASSED] shift_overflow_test
[15:52:32] [PASSED] shift_truncate_test
[15:52:32] [PASSED] shift_nonsense_test
[15:52:32] [PASSED] overflow_allocation_test
[15:52:32] [PASSED] overflow_size_helpers_test
[15:52:32] ==================== [PASSED] overflow =====================
[15:52:32] ============================================================
[15:52:32] Testing complete. Ran 18 tests: passed: 15, skipped: 3
Cc: Nick Desaulniers <ndesaulniers@xxxxxxxxxx>
Cc: Nathan Chancellor <nathan@xxxxxxxxxx>
Cc: Tom Rix <trix@xxxxxxxxxx>
Cc: Daniel Latypov <dlatypov@xxxxxxxxxx>
Cc: "Gustavo A. R. Silva" <gustavoars@xxxxxxxxxx>
Cc: Gwan-gyeong Mun <gwan-gyeong.mun@xxxxxxxxx>
Cc: llvm@xxxxxxxxxxxxxxx
Signed-off-by: Kees Cook <keescook@xxxxxxxxxxxx>
---
lib/overflow_kunit.c | 52 +++++++++++++++++++++++++++++---------------
1 file changed, 35 insertions(+), 17 deletions(-)
diff --git a/lib/overflow_kunit.c b/lib/overflow_kunit.c
index 2914c9d36b0f..3062b33e4bb1 100644
--- a/lib/overflow_kunit.c
+++ b/lib/overflow_kunit.c
@@ -16,6 +16,34 @@
#include <linux/types.h>
#include <linux/vmalloc.h>
+#define SKIP(cond, reason) do { \
+ if (cond) { \
+ kunit_skip(test, reason); \
+ return; \
+ } \
+} while (0)
+
+/*
+ * Clang 11 and earlier generate unwanted libcalls for signed output
+ * on unsigned input.
+ */
+#if defined(CONFIG_CC_IS_CLANG) && __clang_major__ <= 11
+# define SKIP_SIGN_MISMATCH(t) SKIP(t, "Clang 11 unwanted libcalls")
+#else
+# define SKIP_SIGN_MISMATCH(t) do { } while (0)
+#endif
+
+/*
+ * Clang 13 and earlier generate unwanted libcalls for 64-bit tests on
+ * 32-bit hosts.
+ */
+#if defined(CONFIG_CC_IS_CLANG) && __clang_major__ <= 13 && \
+ BITS_PER_LONG != 64
+# define SKIP_64_ON_32(t) SKIP(t, "Clang 13 unwanted libcalls")
+#else
+# define SKIP_64_ON_32(t) do { } while (0)
+#endif
+
#define DEFINE_TEST_ARRAY_TYPED(t1, t2, t) \
static const struct test_ ## t1 ## _ ## t2 ## __ ## t { \
t1 a; \
@@ -94,7 +122,6 @@ DEFINE_TEST_ARRAY(u32) = {
{-4U, 5U, 1U, -9U, -20U, true, false, true},
};
-#if BITS_PER_LONG == 64
DEFINE_TEST_ARRAY(u64) = {
{0, 0, 0, 0, 0, false, false, false},
{1, 1, 2, 0, 1, false, false, false},
@@ -118,7 +145,6 @@ DEFINE_TEST_ARRAY(u64) = {
false, true, false},
{-15ULL, 10ULL, -5ULL, -25ULL, -150ULL, false, false, true},
};
-#endif
DEFINE_TEST_ARRAY(s8) = {
{0, 0, 0, 0, 0, false, false, false},
@@ -194,7 +220,6 @@ DEFINE_TEST_ARRAY(s32) = {
{S32_MAX, S32_MAX, -2, 0, 1, true, false, true},
};
-#if BITS_PER_LONG == 64
DEFINE_TEST_ARRAY(s64) = {
{0, 0, 0, 0, 0, false, false, false},
@@ -223,7 +248,6 @@ DEFINE_TEST_ARRAY(s64) = {
{-128, -1, -129, -127, 128, false, false, false},
{0, -S64_MAX, -S64_MAX, S64_MAX, 0, false, false, false},
};
-#endif
#define check_one_op(t, fmt, op, sym, a, b, r, of) do { \
int _a_orig = a, _a_bump = a + 1; \
@@ -246,7 +270,7 @@ DEFINE_TEST_ARRAY(s64) = {
#define DEFINE_TEST_FUNC_TYPED(n, t, fmt) \
static void do_test_ ## n(struct kunit *test, const struct test_ ## n *p) \
-{ \
+{ \
check_one_op(t, fmt, add, "+", p->a, p->b, p->sum, p->s_of); \
check_one_op(t, fmt, add, "+", p->b, p->a, p->sum, p->s_of); \
check_one_op(t, fmt, sub, "-", p->a, p->b, p->diff, p->d_of); \
@@ -254,10 +278,15 @@ static void do_test_ ## n(struct kunit *test, const struct test_ ## n *p) \
check_one_op(t, fmt, mul, "*", p->b, p->a, p->prod, p->p_of); \
} \
\
-__maybe_unused \
static void n ## _overflow_test(struct kunit *test) { \
unsigned i; \
\
+ SKIP_64_ON_32(__same_type(t, u64)); \
+ SKIP_64_ON_32(__same_type(t, s64)); \
+ SKIP_SIGN_MISMATCH(__same_type(n ## _tests[0].a, u32) && \
+ __same_type(n ## _tests[0].b, u32) && \
+ __same_type(n ## _tests[0].sum, int)); \
+ \
for (i = 0; i < ARRAY_SIZE(n ## _tests); ++i) \
do_test_ ## n(test, &n ## _tests[i]); \
kunit_info(test, "%zu %s arithmetic tests finished\n", \
@@ -273,10 +302,8 @@ DEFINE_TEST_FUNC(u16, "%d");
DEFINE_TEST_FUNC(s16, "%d");
DEFINE_TEST_FUNC(u32, "%u");
DEFINE_TEST_FUNC(s32, "%d");
-#if BITS_PER_LONG == 64
DEFINE_TEST_FUNC(u64, "%llu");
DEFINE_TEST_FUNC(s64, "%lld");
-#endif
DEFINE_TEST_ARRAY_TYPED(u32, u32, u8) = {
{0, 0, 0, 0, 0, false, false, false},
@@ -716,18 +743,9 @@ static struct kunit_case overflow_test_cases[] = {
KUNIT_CASE(s16_s16__s16_overflow_test),
KUNIT_CASE(u32_u32__u32_overflow_test),
KUNIT_CASE(s32_s32__s32_overflow_test),
-/* Clang 13 and earlier generate unwanted libcalls on 32-bit. */
-#if BITS_PER_LONG == 64
KUNIT_CASE(u64_u64__u64_overflow_test),
KUNIT_CASE(s64_s64__s64_overflow_test),
-#endif
-/*
- * Clang 11 and earlier generate unwanted libcalls for signed output, unsigned
- * input.
- */
-#if !(defined(CONFIG_CC_IS_CLANG) && __clang_major__ <= 11)
KUNIT_CASE(u32_u32__int_overflow_test),
-#endif
KUNIT_CASE(u32_u32__u8_overflow_test),
KUNIT_CASE(u8_u8__int_overflow_test),
KUNIT_CASE(int_int__u8_overflow_test),