From: Kees Cook <keesc...@chromium.org>

Implement a robust overflows_type() macro to test if a variable or
constant value would overflow another variable or type. This can be
used as a constant expression for static_assert() (which requires a
constant expression[1][2]) when used on constant values. This must be
constructed manually, since __builtin_add_overflow() does not produce
a constant expression[3].

Additionally adds castable_to_type(), similar to __same_type(), but for
checking if a constant value would overflow if cast to a given type.

Add unit tests for overflows_type(), __same_type(), and castable_to_type()
to the existing KUnit "overflow" test.

[1] https://en.cppreference.com/w/c/language/_Static_assert
[2] C11 standard (ISO/IEC 9899:2011): 6.7.10 Static assertions
[3] https://gcc.gnu.org/onlinedocs/gcc/Integer-Overflow-Builtins.html
    6.56 Built-in Functions to Perform Arithmetic with Overflow Checking
    Built-in Function: bool __builtin_add_overflow (type1 a, type2 b,

v3: Chagne to use uintptr_t type when checking for overflow of pointer type
    variable

Cc: Luc Van Oostenryck <luc.vanoostenr...@gmail.com>
Cc: Nathan Chancellor <nat...@kernel.org>
Cc: Nick Desaulniers <ndesaulni...@google.com>
Cc: Tom Rix <t...@redhat.com>
Cc: Daniel Latypov <dlaty...@google.com>
Cc: Vitor Massaru Iha <vi...@massaru.org>
Cc: "Gustavo A. R. Silva" <gustavo...@kernel.org>
Cc: linux-harden...@vger.kernel.org
Cc: l...@lists.linux.dev
Co-developed-by: Gwan-gyeong Mun <gwan-gyeong....@intel.com>
Signed-off-by: Gwan-gyeong Mun <gwan-gyeong....@intel.com>
Signed-off-by: Kees Cook <keesc...@chromium.org>
---
 drivers/gpu/drm/i915/i915_user_extensions.c |   2 +-
 drivers/gpu/drm/i915/i915_utils.h           |   4 -
 include/linux/compiler.h                    |   1 +
 include/linux/overflow.h                    |  48 +++
 lib/overflow_kunit.c                        | 388 +++++++++++++++++++-
 5 files changed, 437 insertions(+), 6 deletions(-)

diff --git a/drivers/gpu/drm/i915/i915_user_extensions.c 
b/drivers/gpu/drm/i915/i915_user_extensions.c
index c822d0aafd2d..e3f808372c47 100644
--- a/drivers/gpu/drm/i915/i915_user_extensions.c
+++ b/drivers/gpu/drm/i915/i915_user_extensions.c
@@ -51,7 +51,7 @@ int i915_user_extensions(struct i915_user_extension __user 
*ext,
                        return err;
 
                if (get_user(next, &ext->next_extension) ||
-                   overflows_type(next, ext))
+                   overflows_type(next, uintptr_t))
                        return -EFAULT;
 
                ext = u64_to_user_ptr(next);
diff --git a/drivers/gpu/drm/i915/i915_utils.h 
b/drivers/gpu/drm/i915/i915_utils.h
index 6c14d13364bf..67a66d4d5c70 100644
--- a/drivers/gpu/drm/i915/i915_utils.h
+++ b/drivers/gpu/drm/i915/i915_utils.h
@@ -111,10 +111,6 @@ bool i915_error_injected(void);
 #define range_overflows_end_t(type, start, size, max) \
        range_overflows_end((type)(start), (type)(size), (type)(max))
 
-/* Note we don't consider signbits :| */
-#define overflows_type(x, T) \
-       (sizeof(x) > sizeof(T) && (x) >> BITS_PER_TYPE(T))
-
 #define ptr_mask_bits(ptr, n) ({                                       \
        unsigned long __v = (unsigned long)(ptr);                       \
        (typeof(ptr))(__v & -BIT(n));                                   \
diff --git a/include/linux/compiler.h b/include/linux/compiler.h
index 7713d7bcdaea..c631107e93b1 100644
--- a/include/linux/compiler.h
+++ b/include/linux/compiler.h
@@ -244,6 +244,7 @@ static inline void *offset_to_ptr(const int *off)
  * bool and also pointer types.
  */
 #define is_signed_type(type) (((type)(-1)) < (__force type)1)
+#define is_unsigned_type(type) (!is_signed_type(type))
 
 /*
  * This is needed in functions which generate the stack canary, see
diff --git a/include/linux/overflow.h b/include/linux/overflow.h
index 19dfdd74835e..58eb34aa2af9 100644
--- a/include/linux/overflow.h
+++ b/include/linux/overflow.h
@@ -127,6 +127,54 @@ static inline bool __must_check __must_check_overflow(bool 
overflow)
        (*_d >> _to_shift) != _a);                                      \
 }))
 
+#define __overflows_type_constexpr(x, T) (                     \
+       is_unsigned_type(typeof(x)) ?                           \
+               (x) > type_max(typeof(T)) ? 1 : 0               \
+       : is_unsigned_type(typeof(T)) ?                         \
+               (x) < 0 || (x) > type_max(typeof(T)) ? 1 : 0    \
+               : (x) < type_min(typeof(T)) ||                  \
+                 (x) > type_max(typeof(T)) ? 1 : 0)
+
+#define __overflows_type(x, T)         ({      \
+       typeof(T) v = 0;                        \
+       check_add_overflow((x), v, &v);         \
+})
+
+/**
+ * overflows_type - helper for checking the overflows between value, variables,
+ *                 or data type
+ *
+ * @n: source constant value or variable to be checked
+ * @T: destination variable or data type proposed to store @x
+ *
+ * Compares the @x expression for whether or not it can safely fit in
+ * the storage of the type in @T. @x and @T can have different types.
+ * If @x is a constant expression, this will also resolve to a constant
+ * expression.
+ *
+ * Returns: true if overflow can occur, false otherwise.
+ */
+#define overflows_type(n, T)                                   \
+       __builtin_choose_expr(__is_constexpr(n),                \
+                             __overflows_type_constexpr(n, T), \
+                             __overflows_type(n, T))
+
+/**
+ * castable_to_type - like __same_type(), but also allows for casted literals
+ *
+ * @n: variable or constant value
+ * @T: variable or data type
+ *
+ * Unlike the __same_type() macro, this allows a constant value as the
+ * first argument. If this value would not overflow into an assignment
+ * of the second argument's type, it returns true. Otherwise, this falls
+ * back to __same_type().
+ */
+#define castable_to_type(n, T)                                         \
+       __builtin_choose_expr(__is_constexpr(n),                        \
+                             !__overflows_type_constexpr(n, T),        \
+                             __same_type(n, T))
+
 /**
  * size_mul() - Calculate size_t multiplication with saturation at SIZE_MAX
  *
diff --git a/lib/overflow_kunit.c b/lib/overflow_kunit.c
index 0d98c9bc75da..44da9d190057 100644
--- a/lib/overflow_kunit.c
+++ b/lib/overflow_kunit.c
@@ -16,6 +16,11 @@
 #include <linux/types.h>
 #include <linux/vmalloc.h>
 
+/* We're expecting to do a lot of "always true" or "always false" tests. */
+#ifdef CONFIG_CC_IS_CLANG
+#pragma clang diagnostic ignored "-Wtautological-constant-out-of-range-compare"
+#endif
+
 #define DEFINE_TEST_ARRAY_TYPED(t1, t2, t)                     \
        static const struct test_ ## t1 ## _ ## t2 ## __ ## t { \
                t1 a;                                           \
@@ -246,7 +251,7 @@ 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);   \
@@ -687,6 +692,384 @@ static void overflow_size_helpers_test(struct kunit *test)
 #undef check_one_size_helper
 }
 
+static void overflows_type_test(struct kunit *test)
+{
+       int count = 0;
+       unsigned int var;
+
+#define __TEST_OVERFLOWS_TYPE(func, arg1, arg2, of)    do {            \
+       bool __of = func(arg1, arg2);                                   \
+       KUNIT_EXPECT_EQ_MSG(test, __of, of,                             \
+               "expected " #func "(" #arg1 ", " #arg2 " to%s overflow\n",\
+               of ? "" : " not");                                      \
+       count++;                                                        \
+} while (0)
+
+/* Args are: first type, second type, value, overflow expected */
+#define TEST_OVERFLOWS_TYPE(__t1, __t2, v, of) do {                    \
+       __t1 t1 = (v);                                                  \
+       __t2 t2;                                                        \
+       __TEST_OVERFLOWS_TYPE(__overflows_type, t1, t2, of);            \
+       __TEST_OVERFLOWS_TYPE(__overflows_type, t1, __t2, of);          \
+       __TEST_OVERFLOWS_TYPE(__overflows_type_constexpr, t1, t2, of);  \
+       __TEST_OVERFLOWS_TYPE(__overflows_type_constexpr, t1, __t2, of);\
+} while (0)
+
+       TEST_OVERFLOWS_TYPE(u8, u8, U8_MAX, false);
+       TEST_OVERFLOWS_TYPE(u8, u16, U8_MAX, false);
+       TEST_OVERFLOWS_TYPE(u8, s8, U8_MAX, true);
+       TEST_OVERFLOWS_TYPE(u8, s8, S8_MAX, false);
+       TEST_OVERFLOWS_TYPE(u8, s8, (u8)S8_MAX + 1, true);
+       TEST_OVERFLOWS_TYPE(u8, s16, U8_MAX, false);
+       TEST_OVERFLOWS_TYPE(s8, u8, S8_MAX, false);
+       TEST_OVERFLOWS_TYPE(s8, u8, -1, true);
+       TEST_OVERFLOWS_TYPE(s8, u8, S8_MIN, true);
+       TEST_OVERFLOWS_TYPE(s8, u16, S8_MAX, false);
+       TEST_OVERFLOWS_TYPE(s8, u16, -1, true);
+       TEST_OVERFLOWS_TYPE(s8, u16, S8_MIN, true);
+       TEST_OVERFLOWS_TYPE(s8, u32, S8_MAX, false);
+       TEST_OVERFLOWS_TYPE(s8, u32, -1, true);
+       TEST_OVERFLOWS_TYPE(s8, u32, S8_MIN, true);
+#if BITS_PER_LONG == 64
+       TEST_OVERFLOWS_TYPE(s8, u64, S8_MAX, false);
+       TEST_OVERFLOWS_TYPE(s8, u64, -1, true);
+       TEST_OVERFLOWS_TYPE(s8, u64, S8_MIN, true);
+#endif
+       TEST_OVERFLOWS_TYPE(s8, s8, S8_MAX, false);
+       TEST_OVERFLOWS_TYPE(s8, s8, S8_MIN, false);
+       TEST_OVERFLOWS_TYPE(s8, s16, S8_MAX, false);
+       TEST_OVERFLOWS_TYPE(s8, s16, S8_MIN, false);
+       TEST_OVERFLOWS_TYPE(u16, u8, U8_MAX, false);
+       TEST_OVERFLOWS_TYPE(u16, u8, (u16)U8_MAX + 1, true);
+       TEST_OVERFLOWS_TYPE(u16, u8, U16_MAX, true);
+       TEST_OVERFLOWS_TYPE(u16, s8, S8_MAX, false);
+       TEST_OVERFLOWS_TYPE(u16, s8, (u16)S8_MAX + 1, true);
+       TEST_OVERFLOWS_TYPE(u16, s8, U16_MAX, true);
+       TEST_OVERFLOWS_TYPE(u16, s16, S16_MAX, false);
+       TEST_OVERFLOWS_TYPE(u16, s16, (u16)S16_MAX + 1, true);
+       TEST_OVERFLOWS_TYPE(u16, s16, U16_MAX, true);
+       TEST_OVERFLOWS_TYPE(u16, u32, U16_MAX, false);
+       TEST_OVERFLOWS_TYPE(u16, s32, U16_MAX, false);
+       TEST_OVERFLOWS_TYPE(s16, u8, U8_MAX, false);
+       TEST_OVERFLOWS_TYPE(s16, u8, (s16)U8_MAX + 1, true);
+       TEST_OVERFLOWS_TYPE(s16, u8, -1, true);
+       TEST_OVERFLOWS_TYPE(s16, u8, S16_MIN, true);
+       TEST_OVERFLOWS_TYPE(s16, u16, S16_MAX, false);
+       TEST_OVERFLOWS_TYPE(s16, u16, -1, true);
+       TEST_OVERFLOWS_TYPE(s16, u16, S16_MIN, true);
+       TEST_OVERFLOWS_TYPE(s16, u32, S16_MAX, false);
+       TEST_OVERFLOWS_TYPE(s16, u32, -1, true);
+       TEST_OVERFLOWS_TYPE(s16, u32, S16_MIN, true);
+#if BITS_PER_LONG == 64
+       TEST_OVERFLOWS_TYPE(s16, u64, S16_MAX, false);
+       TEST_OVERFLOWS_TYPE(s16, u64, -1, true);
+       TEST_OVERFLOWS_TYPE(s16, u64, S16_MIN, true);
+#endif
+       TEST_OVERFLOWS_TYPE(s16, s8, S8_MAX, false);
+       TEST_OVERFLOWS_TYPE(s16, s8, S8_MIN, false);
+       TEST_OVERFLOWS_TYPE(s16, s8, (s16)S8_MAX + 1, true);
+       TEST_OVERFLOWS_TYPE(s16, s8, (s16)S8_MIN - 1, true);
+       TEST_OVERFLOWS_TYPE(s16, s8, S16_MAX, true);
+       TEST_OVERFLOWS_TYPE(s16, s8, S16_MIN, true);
+       TEST_OVERFLOWS_TYPE(s16, s16, S16_MAX, false);
+       TEST_OVERFLOWS_TYPE(s16, s16, S16_MIN, false);
+       TEST_OVERFLOWS_TYPE(s16, s32, S16_MAX, false);
+       TEST_OVERFLOWS_TYPE(s16, s32, S16_MIN, false);
+       TEST_OVERFLOWS_TYPE(u32, u8, U8_MAX, false);
+       TEST_OVERFLOWS_TYPE(u32, u8, (u32)U8_MAX + 1, true);
+       TEST_OVERFLOWS_TYPE(u32, u8, U32_MAX, true);
+       TEST_OVERFLOWS_TYPE(u32, s8, S8_MAX, false);
+       TEST_OVERFLOWS_TYPE(u32, s8, (u32)S8_MAX + 1, true);
+       TEST_OVERFLOWS_TYPE(u32, s8, U32_MAX, true);
+       TEST_OVERFLOWS_TYPE(u32, u16, U16_MAX, false);
+       TEST_OVERFLOWS_TYPE(u32, u16, U16_MAX + 1, true);
+       TEST_OVERFLOWS_TYPE(u32, u16, U32_MAX, true);
+       TEST_OVERFLOWS_TYPE(u32, s16, S16_MAX, false);
+       TEST_OVERFLOWS_TYPE(u32, s16, (u32)S16_MAX + 1, true);
+       TEST_OVERFLOWS_TYPE(u32, s16, U32_MAX, true);
+       TEST_OVERFLOWS_TYPE(u32, u32, U32_MAX, false);
+       TEST_OVERFLOWS_TYPE(u32, s32, S32_MAX, false);
+       TEST_OVERFLOWS_TYPE(u32, s32, U32_MAX, true);
+       TEST_OVERFLOWS_TYPE(u32, s32, (u32)S32_MAX + 1, true);
+#if BITS_PER_LONG == 64
+       TEST_OVERFLOWS_TYPE(u32, u64, U32_MAX, false);
+       TEST_OVERFLOWS_TYPE(u32, s64, U32_MAX, false);
+#endif
+       TEST_OVERFLOWS_TYPE(s32, u8, U8_MAX, false);
+       TEST_OVERFLOWS_TYPE(s32, u8, (s32)U8_MAX + 1, true);
+       TEST_OVERFLOWS_TYPE(s32, u16, S32_MAX, true);
+       TEST_OVERFLOWS_TYPE(s32, u8, -1, true);
+       TEST_OVERFLOWS_TYPE(s32, u8, S32_MIN, true);
+       TEST_OVERFLOWS_TYPE(s32, u16, U16_MAX, false);
+       TEST_OVERFLOWS_TYPE(s32, u16, (s32)U16_MAX + 1, true);
+       TEST_OVERFLOWS_TYPE(s32, u16, S32_MAX, true);
+       TEST_OVERFLOWS_TYPE(s32, u16, -1, true);
+       TEST_OVERFLOWS_TYPE(s32, u16, S32_MIN, true);
+       TEST_OVERFLOWS_TYPE(s32, u32, S32_MAX, false);
+       TEST_OVERFLOWS_TYPE(s32, u32, -1, true);
+       TEST_OVERFLOWS_TYPE(s32, u32, S32_MIN, true);
+#if BITS_PER_LONG == 64
+       TEST_OVERFLOWS_TYPE(s32, u64, S32_MAX, false);
+       TEST_OVERFLOWS_TYPE(s32, u64, -1, true);
+       TEST_OVERFLOWS_TYPE(s32, u64, S32_MIN, true);
+#endif
+       TEST_OVERFLOWS_TYPE(s32, s8, S8_MAX, false);
+       TEST_OVERFLOWS_TYPE(s32, s8, S8_MIN, false);
+       TEST_OVERFLOWS_TYPE(s32, s8, (s32)S8_MAX + 1, true);
+       TEST_OVERFLOWS_TYPE(s32, s8, (s32)S8_MIN - 1, true);
+       TEST_OVERFLOWS_TYPE(s32, s8, S32_MAX, true);
+       TEST_OVERFLOWS_TYPE(s32, s8, S32_MIN, true);
+       TEST_OVERFLOWS_TYPE(s32, s16, S16_MAX, false);
+       TEST_OVERFLOWS_TYPE(s32, s16, S16_MIN, false);
+       TEST_OVERFLOWS_TYPE(s32, s16, (s32)S16_MAX + 1, true);
+       TEST_OVERFLOWS_TYPE(s32, s16, (s32)S16_MIN - 1, true);
+       TEST_OVERFLOWS_TYPE(s32, s16, S32_MAX, true);
+       TEST_OVERFLOWS_TYPE(s32, s16, S32_MIN, true);
+       TEST_OVERFLOWS_TYPE(s32, s32, S32_MAX, false);
+       TEST_OVERFLOWS_TYPE(s32, s32, S32_MIN, false);
+#if BITS_PER_LONG == 64
+       TEST_OVERFLOWS_TYPE(s32, s64, S32_MAX, false);
+       TEST_OVERFLOWS_TYPE(s32, s64, S32_MIN, false);
+       TEST_OVERFLOWS_TYPE(u64, u8, U64_MAX, true);
+       TEST_OVERFLOWS_TYPE(u64, u8, U8_MAX, false);
+       TEST_OVERFLOWS_TYPE(u64, u8, (u64)U8_MAX + 1, true);
+       TEST_OVERFLOWS_TYPE(u64, u16, U64_MAX, true);
+       TEST_OVERFLOWS_TYPE(u64, u16, U16_MAX, false);
+       TEST_OVERFLOWS_TYPE(u64, u16, (u64)U16_MAX + 1, true);
+       TEST_OVERFLOWS_TYPE(u64, u32, U64_MAX, true);
+       TEST_OVERFLOWS_TYPE(u64, u32, U32_MAX, false);
+       TEST_OVERFLOWS_TYPE(u64, u32, (u64)U32_MAX + 1, true);
+       TEST_OVERFLOWS_TYPE(u64, u64, U64_MAX, false);
+       TEST_OVERFLOWS_TYPE(u64, s8, S8_MAX, false);
+       TEST_OVERFLOWS_TYPE(u64, s8, (u64)S8_MAX + 1, true);
+       TEST_OVERFLOWS_TYPE(u64, s8, U64_MAX, true);
+       TEST_OVERFLOWS_TYPE(u64, s16, S16_MAX, false);
+       TEST_OVERFLOWS_TYPE(u64, s16, (u64)S16_MAX + 1, true);
+       TEST_OVERFLOWS_TYPE(u64, s16, U64_MAX, true);
+       TEST_OVERFLOWS_TYPE(u64, s32, S32_MAX, false);
+       TEST_OVERFLOWS_TYPE(u64, s32, (u64)S32_MAX + 1, true);
+       TEST_OVERFLOWS_TYPE(u64, s32, U64_MAX, true);
+       TEST_OVERFLOWS_TYPE(u64, s64, S64_MAX, false);
+       TEST_OVERFLOWS_TYPE(u64, s64, U64_MAX, true);
+       TEST_OVERFLOWS_TYPE(u64, s64, (u64)S64_MAX + 1, true);
+       TEST_OVERFLOWS_TYPE(s64, u8, S64_MAX, true);
+       TEST_OVERFLOWS_TYPE(s64, u8, S64_MIN, true);
+       TEST_OVERFLOWS_TYPE(s64, u8, -1, true);
+       TEST_OVERFLOWS_TYPE(s64, u8, U8_MAX, false);
+       TEST_OVERFLOWS_TYPE(s64, u8, (s64)U8_MAX + 1, true);
+       TEST_OVERFLOWS_TYPE(s64, u16, S64_MAX, true);
+       TEST_OVERFLOWS_TYPE(s64, u16, S64_MIN, true);
+       TEST_OVERFLOWS_TYPE(s64, u16, -1, true);
+       TEST_OVERFLOWS_TYPE(s64, u16, U16_MAX, false);
+       TEST_OVERFLOWS_TYPE(s64, u16, (s64)U16_MAX + 1, true);
+       TEST_OVERFLOWS_TYPE(s64, u32, S64_MAX, true);
+       TEST_OVERFLOWS_TYPE(s64, u32, S64_MIN, true);
+       TEST_OVERFLOWS_TYPE(s64, u32, -1, true);
+       TEST_OVERFLOWS_TYPE(s64, u32, U32_MAX, false);
+       TEST_OVERFLOWS_TYPE(s64, u32, (s64)U32_MAX + 1, true);
+       TEST_OVERFLOWS_TYPE(s64, u64, S64_MAX, false);
+       TEST_OVERFLOWS_TYPE(s64, u64, S64_MIN, true);
+       TEST_OVERFLOWS_TYPE(s64, u64, -1, true);
+       TEST_OVERFLOWS_TYPE(s64, s8, S8_MAX, false);
+       TEST_OVERFLOWS_TYPE(s64, s8, S8_MIN, false);
+       TEST_OVERFLOWS_TYPE(s64, s8, (s64)S8_MAX + 1, true);
+       TEST_OVERFLOWS_TYPE(s64, s8, (s64)S8_MIN - 1, true);
+       TEST_OVERFLOWS_TYPE(s64, s8, S64_MAX, true);
+       TEST_OVERFLOWS_TYPE(s64, s16, S16_MAX, false);
+       TEST_OVERFLOWS_TYPE(s64, s16, S16_MIN, false);
+       TEST_OVERFLOWS_TYPE(s64, s16, (s64)S16_MAX + 1, true);
+       TEST_OVERFLOWS_TYPE(s64, s16, (s64)S16_MIN - 1, true);
+       TEST_OVERFLOWS_TYPE(s64, s16, S64_MAX, true);
+       TEST_OVERFLOWS_TYPE(s64, s32, S32_MAX, false);
+       TEST_OVERFLOWS_TYPE(s64, s32, S32_MIN, false);
+       TEST_OVERFLOWS_TYPE(s64, s32, (s64)S32_MAX + 1, true);
+       TEST_OVERFLOWS_TYPE(s64, s32, (s64)S32_MIN - 1, true);
+       TEST_OVERFLOWS_TYPE(s64, s32, S64_MAX, true);
+       TEST_OVERFLOWS_TYPE(s64, s64, S64_MAX, false);
+       TEST_OVERFLOWS_TYPE(s64, s64, S64_MIN, false);
+#endif
+
+       /* Check for macro side-effects. */
+       var = INT_MAX - 1;
+       __TEST_OVERFLOWS_TYPE(__overflows_type, var++, int, false);
+       __TEST_OVERFLOWS_TYPE(__overflows_type, var++, int, false);
+       __TEST_OVERFLOWS_TYPE(__overflows_type, var++, int, true);
+       var = INT_MAX - 1;
+       __TEST_OVERFLOWS_TYPE(overflows_type, var++, int, false);
+       __TEST_OVERFLOWS_TYPE(overflows_type, var++, int, false);
+       __TEST_OVERFLOWS_TYPE(overflows_type, var++, int, true);
+
+       kunit_info(test, "%d overflows_type() tests finished\n", count);
+#undef TEST_OVERFLOWS_TYPE
+#undef __TEST_OVERFLOWS_TYPE
+}
+
+static void same_type_test(struct kunit *test)
+{
+       int count = 0;
+       int var;
+
+#define TEST_SAME_TYPE(t1, t2, same)                   do {    \
+       typeof(t1) __t1h = type_max(t1);                        \
+       typeof(t1) __t1l = type_min(t1);                        \
+       typeof(t2) __t2h = type_max(t2);                        \
+       typeof(t2) __t2l = type_min(t2);                        \
+       KUNIT_EXPECT_EQ(test, true, __same_type(t1, __t1h));    \
+       KUNIT_EXPECT_EQ(test, true, __same_type(t1, __t1l));    \
+       KUNIT_EXPECT_EQ(test, true, __same_type(__t1h, t1));    \
+       KUNIT_EXPECT_EQ(test, true, __same_type(__t1l, t1));    \
+       KUNIT_EXPECT_EQ(test, true, __same_type(t2, __t2h));    \
+       KUNIT_EXPECT_EQ(test, true, __same_type(t2, __t2l));    \
+       KUNIT_EXPECT_EQ(test, true, __same_type(__t2h, t2));    \
+       KUNIT_EXPECT_EQ(test, true, __same_type(__t2l, t2));    \
+       KUNIT_EXPECT_EQ(test, same, __same_type(t1, t2));       \
+       KUNIT_EXPECT_EQ(test, same, __same_type(t2, __t1h));    \
+       KUNIT_EXPECT_EQ(test, same, __same_type(t2, __t1l));    \
+       KUNIT_EXPECT_EQ(test, same, __same_type(__t1h, t2));    \
+       KUNIT_EXPECT_EQ(test, same, __same_type(__t1l, t2));    \
+       KUNIT_EXPECT_EQ(test, same, __same_type(t1, __t2h));    \
+       KUNIT_EXPECT_EQ(test, same, __same_type(t1, __t2l));    \
+       KUNIT_EXPECT_EQ(test, same, __same_type(__t2h, t1));    \
+       KUNIT_EXPECT_EQ(test, same, __same_type(__t2l, t1));    \
+} while (0)
+
+#if BITS_PER_LONG == 64
+# define TEST_SAME_TYPE64(base, t, m)  TEST_SAME_TYPE(base, t, m)
+#else
+# define TEST_SAME_TYPE64(base, t, m)  do { } while (0)
+#endif
+
+#define TEST_TYPE_SETS(base, mu8, mu16, mu32, ms8, ms16, ms32, mu64, ms64) \
+do {                                                                   \
+       TEST_SAME_TYPE(base,  u8,  mu8);                                \
+       TEST_SAME_TYPE(base, u16, mu16);                                \
+       TEST_SAME_TYPE(base, u32, mu32);                                \
+       TEST_SAME_TYPE(base,  s8,  ms8);                                \
+       TEST_SAME_TYPE(base, s16, ms16);                                \
+       TEST_SAME_TYPE(base, s32, ms32);                                \
+       TEST_SAME_TYPE64(base, u64, mu64);                              \
+       TEST_SAME_TYPE64(base, s64, ms64);                              \
+} while (0)
+
+       TEST_TYPE_SETS(u8,   true, false, false, false, false, false, false, 
false);
+       TEST_TYPE_SETS(u16, false,  true, false, false, false, false, false, 
false);
+       TEST_TYPE_SETS(u32, false, false,  true, false, false, false, false, 
false);
+       TEST_TYPE_SETS(s8,  false, false, false,  true, false, false, false, 
false);
+       TEST_TYPE_SETS(s16, false, false, false, false,  true, false, false, 
false);
+       TEST_TYPE_SETS(s32, false, false, false, false, false,  true, false, 
false);
+#if BITS_PER_LONG == 64
+       TEST_TYPE_SETS(u64, false, false, false, false, false, false,  true, 
false);
+       TEST_TYPE_SETS(s64, false, false, false, false, false, false, false,  
true);
+#endif
+
+       /* Check for macro side-effects. */
+       var = 4;
+       KUNIT_EXPECT_EQ(test, var, 4);
+       KUNIT_EXPECT_TRUE(test, __same_type(var++, int));
+       KUNIT_EXPECT_EQ(test, var, 4);
+       KUNIT_EXPECT_TRUE(test, __same_type(int, var++));
+       KUNIT_EXPECT_EQ(test, var, 4);
+       KUNIT_EXPECT_TRUE(test, __same_type(var++, var++));
+       KUNIT_EXPECT_EQ(test, var, 4);
+
+       kunit_info(test, "%d __same_type() tests finished\n", count);
+
+#undef TEST_TYPE_SETS
+#undef TEST_SAME_TYPE64
+#undef TEST_SAME_TYPE
+}
+
+static void castable_to_type_test(struct kunit *test)
+{
+       int count = 0;
+
+#define TEST_CASTABLE_TO_TYPE(arg1, arg2, pass)        do {    \
+       bool __pass = castable_to_type(arg1, arg2);             \
+       KUNIT_EXPECT_EQ_MSG(test, __pass, pass,                 \
+               "expected castable_to_type(" #arg1 ", " #arg2 ") to%s pass\n",\
+               pass ? "" : " not");                            \
+       count++;                                                \
+} while (0)
+
+       TEST_CASTABLE_TO_TYPE(16, u8, true);
+       TEST_CASTABLE_TO_TYPE(16, u16, true);
+       TEST_CASTABLE_TO_TYPE(16, u32, true);
+       TEST_CASTABLE_TO_TYPE(16, s8, true);
+       TEST_CASTABLE_TO_TYPE(16, s16, true);
+       TEST_CASTABLE_TO_TYPE(16, s32, true);
+       TEST_CASTABLE_TO_TYPE(-16, s8, true);
+       TEST_CASTABLE_TO_TYPE(-16, s16, true);
+       TEST_CASTABLE_TO_TYPE(-16, s32, true);
+#if BITS_PER_LONG == 64
+       TEST_CASTABLE_TO_TYPE(16, u64, true);
+       TEST_CASTABLE_TO_TYPE(-16, s64, true);
+#endif
+
+#define TEST_CASTABLE_TO_TYPE_VAR(width)       do {                            
\
+       u ## width u ## width ## var = 0;                                       
\
+       s ## width s ## width ## var = 0;                                       
\
+                                                                               
\
+       /* Constant expressions that fit types. */                              
\
+       TEST_CASTABLE_TO_TYPE(type_max(u ## width), u ## width, true);          
\
+       TEST_CASTABLE_TO_TYPE(type_min(u ## width), u ## width, true);          
\
+       TEST_CASTABLE_TO_TYPE(type_max(u ## width), u ## width ## var, true);   
\
+       TEST_CASTABLE_TO_TYPE(type_min(u ## width), u ## width ## var, true);   
\
+       TEST_CASTABLE_TO_TYPE(type_max(s ## width), s ## width, true);          
\
+       TEST_CASTABLE_TO_TYPE(type_min(s ## width), s ## width, true);          
\
+       TEST_CASTABLE_TO_TYPE(type_max(s ## width), s ## width ## var, true);   
\
+       TEST_CASTABLE_TO_TYPE(type_min(u ## width), s ## width ## var, true);   
\
+       /* Constant expressions that do not fit types. */                       
\
+       TEST_CASTABLE_TO_TYPE(type_max(u ## width), s ## width, false);         
\
+       TEST_CASTABLE_TO_TYPE(type_max(u ## width), s ## width ## var, false);  
\
+       TEST_CASTABLE_TO_TYPE(type_min(s ## width), u ## width, false);         
\
+       TEST_CASTABLE_TO_TYPE(type_min(s ## width), u ## width ## var, false);  
\
+       /* Non-constant expression with mismatched type. */                     
\
+       TEST_CASTABLE_TO_TYPE(s ## width ## var, u ## width, false);            
\
+       TEST_CASTABLE_TO_TYPE(u ## width ## var, s ## width, false);            
\
+} while (0)
+
+#define TEST_CASTABLE_TO_TYPE_RANGE(width)     do {                            
\
+       unsigned long big = U ## width ## _MAX;                                 
\
+       signed long small = S ## width ## _MIN;                                 
\
+       u ## width u ## width ## var = 0;                                       
\
+       s ## width s ## width ## var = 0;                                       
\
+                                                                               
\
+       /* Constant expression in range. */                                     
\
+       TEST_CASTABLE_TO_TYPE(U ## width ## _MAX, u ## width, true);            
\
+       TEST_CASTABLE_TO_TYPE(U ## width ## _MAX, u ## width ## var, true);     
\
+       TEST_CASTABLE_TO_TYPE(S ## width ## _MIN, s ## width, true);            
\
+       TEST_CASTABLE_TO_TYPE(S ## width ## _MIN, s ## width ## var, true);     
\
+       /* Constant expression out of range. */                                 
\
+       TEST_CASTABLE_TO_TYPE((unsigned long)U ## width ## _MAX + 1, u ## 
width, false); \
+       TEST_CASTABLE_TO_TYPE((unsigned long)U ## width ## _MAX + 1, u ## width 
## var, false); \
+       TEST_CASTABLE_TO_TYPE((signed long)S ## width ## _MIN - 1, s ## width, 
false); \
+       TEST_CASTABLE_TO_TYPE((signed long)S ## width ## _MIN - 1, s ## width 
## var, false); \
+       /* Non-constant expression with mismatched type. */                     
\
+       TEST_CASTABLE_TO_TYPE(big, u ## width, false);                          
\
+       TEST_CASTABLE_TO_TYPE(big, u ## width ## var, false);                   
\
+       TEST_CASTABLE_TO_TYPE(small, s ## width, false);                        
\
+       TEST_CASTABLE_TO_TYPE(small, s ## width ## var, false);                 
\
+} while (0)
+
+       TEST_CASTABLE_TO_TYPE_VAR(8);
+       TEST_CASTABLE_TO_TYPE_VAR(16);
+       TEST_CASTABLE_TO_TYPE_VAR(32);
+#if BITS_PER_LONG == 64
+       TEST_CASTABLE_TO_TYPE_VAR(64);
+#endif
+
+       TEST_CASTABLE_TO_TYPE_RANGE(8);
+       TEST_CASTABLE_TO_TYPE_RANGE(16);
+#if BITS_PER_LONG == 64
+       TEST_CASTABLE_TO_TYPE_RANGE(32);
+#endif
+       kunit_info(test, "%d castable_to_type() tests finished\n", count);
+
+#undef TEST_CASTABLE_TO_TYPE_RANGE
+#undef TEST_CASTABLE_TO_TYPE_VAR
+#undef TEST_CASTABLE_TO_TYPE
+}
+
 static struct kunit_case overflow_test_cases[] = {
        KUNIT_CASE(u8_u8__u8_overflow_test),
        KUNIT_CASE(s8_s8__s8_overflow_test),
@@ -706,6 +1089,9 @@ static struct kunit_case overflow_test_cases[] = {
        KUNIT_CASE(overflow_shift_test),
        KUNIT_CASE(overflow_allocation_test),
        KUNIT_CASE(overflow_size_helpers_test),
+       KUNIT_CASE(overflows_type_test),
+       KUNIT_CASE(same_type_test),
+       KUNIT_CASE(castable_to_type_test),
        {}
 };
 
-- 
2.37.1

Reply via email to