Merge tag 'overflow-v5.10-rc1' of git://git.kernel.org/pub/scm/linux/kernel/git/kees/linux (b5fc7a89) · Commits · 戴 / test

include/linux/overflow.h

+24 −15

Original line number	Diff line number	Diff line
		@@ -43,6 +43,16 @@
		#define is_non_negative(a) ((a) > 0 \|\| (a) == 0)
		#define is_negative(a) (!(is_non_negative(a)))

		/*
		* Allows for effectively applying __must_check to a macro so we can have
		* both the type-agnostic benefits of the macros while also being able to
		* enforce that the return value is, in fact, checked.
		*/
		static inline bool __must_check __must_check_overflow(bool overflow)
		{
		return unlikely(overflow);
		}

		#ifdef COMPILER_HAS_GENERIC_BUILTIN_OVERFLOW
		/*
		* For simplicity and code hygiene, the fallback code below insists on
		@@ -52,32 +62,32 @@
		* alias for __builtin_add_overflow, but add type checks similar to
		* below.
		*/
		#define check_add_overflow(a, b, d) ({ \
		#define check_add_overflow(a, b, d) __must_check_overflow(({ \
		typeof(a) __a = (a); \
		typeof(b) __b = (b); \
		typeof(d) __d = (d); \
		(void) (&__a == &__b); \
		(void) (&__a == __d); \
		__builtin_add_overflow(__a, __b, __d); \
		})
		}))

		#define check_sub_overflow(a, b, d) ({ \
		#define check_sub_overflow(a, b, d) __must_check_overflow(({ \
		typeof(a) __a = (a); \
		typeof(b) __b = (b); \
		typeof(d) __d = (d); \
		(void) (&__a == &__b); \
		(void) (&__a == __d); \
		__builtin_sub_overflow(__a, __b, __d); \
		})
		}))

		#define check_mul_overflow(a, b, d) ({ \
		#define check_mul_overflow(a, b, d) __must_check_overflow(({ \
		typeof(a) __a = (a); \
		typeof(b) __b = (b); \
		typeof(d) __d = (d); \
		(void) (&__a == &__b); \
		(void) (&__a == __d); \
		__builtin_mul_overflow(__a, __b, __d); \
		})
		}))

		#else

		@@ -190,21 +200,20 @@
		})


		#define check_add_overflow(a, b, d) \
		#define check_add_overflow(a, b, d) __must_check_overflow( \
		__builtin_choose_expr(is_signed_type(typeof(a)), \
		__signed_add_overflow(a, b, d), \
		__unsigned_add_overflow(a, b, d))
		__unsigned_add_overflow(a, b, d)))

		#define check_sub_overflow(a, b, d) \
		#define check_sub_overflow(a, b, d) __must_check_overflow( \
		__builtin_choose_expr(is_signed_type(typeof(a)), \
		__signed_sub_overflow(a, b, d), \
		__unsigned_sub_overflow(a, b, d))
		__unsigned_sub_overflow(a, b, d)))

		#define check_mul_overflow(a, b, d) \
		#define check_mul_overflow(a, b, d) __must_check_overflow( \
		__builtin_choose_expr(is_signed_type(typeof(a)), \
		__signed_mul_overflow(a, b, d), \
		__unsigned_mul_overflow(a, b, d))

		__unsigned_mul_overflow(a, b, d)))

		#endif /* COMPILER_HAS_GENERIC_BUILTIN_OVERFLOW */

		@@ -227,7 +236,7 @@
		* '*d' will hold the results of the attempted shift, but is not
		* considered "safe for use" if false is returned.
		*/
		#define check_shl_overflow(a, s, d) ({ \
		#define check_shl_overflow(a, s, d) __must_check_overflow(({ \
		typeof(a) _a = a; \
		typeof(s) _s = s; \
		typeof(d) _d = d; \
		@@ -237,7 +246,7 @@
		*_d = (_a_full << _to_shift); \
		(_to_shift != _s \|\| is_negative(*_d) \|\| is_negative(_a) \|\| \
		(*_d >> _to_shift) != _a); \
		})
		}))

		/**
		* array_size() - Calculate size of 2-dimensional array.

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