linux_kernel/include/asm-generic/atomic-instrumented.h

/*
 * This file provides wrappers with KASAN instrumentation for atomic operations.
 * To use this functionality an arch's atomic.h file needs to define all
 * atomic operations with arch_ prefix (e.g. arch_atomic_read()) and include
 * this file at the end. This file provides atomic_read() that forwards to
 * arch_atomic_read() for actual atomic operation.
 * Note: if an arch atomic operation is implemented by means of other atomic
 * operations (e.g. atomic_read()/atomic_cmpxchg() loop), then it needs to use
 * arch_ variants (i.e. arch_atomic_read()/arch_atomic_cmpxchg()) to avoid
 * double instrumentation.
 */

#ifndef _LINUX_ATOMIC_INSTRUMENTED_H
#define _LINUX_ATOMIC_INSTRUMENTED_H

#include <linux/build_bug.h>
#include <linux/kasan-checks.h>

static __always_inline int atomic_read(const atomic_t *v)
{
	kasan_check_read(v, sizeof(*v));
	return arch_atomic_read(v);
}

static __always_inline s64 atomic64_read(const atomic64_t *v)
{
	kasan_check_read(v, sizeof(*v));
	return arch_atomic64_read(v);
}

static __always_inline void atomic_set(atomic_t *v, int i)
{
	kasan_check_write(v, sizeof(*v));
	arch_atomic_set(v, i);
}

static __always_inline void atomic64_set(atomic64_t *v, s64 i)
{
	kasan_check_write(v, sizeof(*v));
	arch_atomic64_set(v, i);
}

static __always_inline int atomic_xchg(atomic_t *v, int i)
{
	kasan_check_write(v, sizeof(*v));
	return arch_atomic_xchg(v, i);
}

static __always_inline s64 atomic64_xchg(atomic64_t *v, s64 i)
{
	kasan_check_write(v, sizeof(*v));
	return arch_atomic64_xchg(v, i);
}

static __always_inline int atomic_cmpxchg(atomic_t *v, int old, int new)
{
	kasan_check_write(v, sizeof(*v));
	return arch_atomic_cmpxchg(v, old, new);
}

static __always_inline s64 atomic64_cmpxchg(atomic64_t *v, s64 old, s64 new)
{
	kasan_check_write(v, sizeof(*v));
	return arch_atomic64_cmpxchg(v, old, new);
}

#ifdef arch_atomic_try_cmpxchg
#define atomic_try_cmpxchg atomic_try_cmpxchg
static __always_inline bool atomic_try_cmpxchg(atomic_t *v, int *old, int new)
{
	kasan_check_write(v, sizeof(*v));
	kasan_check_read(old, sizeof(*old));
	return arch_atomic_try_cmpxchg(v, old, new);
}
#endif

#ifdef arch_atomic64_try_cmpxchg
#define atomic64_try_cmpxchg atomic64_try_cmpxchg
static __always_inline bool atomic64_try_cmpxchg(atomic64_t *v, s64 *old, s64 new)
{
	kasan_check_write(v, sizeof(*v));
	kasan_check_read(old, sizeof(*old));
	return arch_atomic64_try_cmpxchg(v, old, new);
}
#endif

static __always_inline int __atomic_add_unless(atomic_t *v, int a, int u)
{
	kasan_check_write(v, sizeof(*v));
	return __arch_atomic_add_unless(v, a, u);
}


static __always_inline bool atomic64_add_unless(atomic64_t *v, s64 a, s64 u)
{
	kasan_check_write(v, sizeof(*v));
	return arch_atomic64_add_unless(v, a, u);
}

static __always_inline void atomic_inc(atomic_t *v)
{
	kasan_check_write(v, sizeof(*v));
	arch_atomic_inc(v);
}

static __always_inline void atomic64_inc(atomic64_t *v)
{
	kasan_check_write(v, sizeof(*v));
	arch_atomic64_inc(v);
}

static __always_inline void atomic_dec(atomic_t *v)
{
	kasan_check_write(v, sizeof(*v));
	arch_atomic_dec(v);
}

static __always_inline void atomic64_dec(atomic64_t *v)
{
	kasan_check_write(v, sizeof(*v));
	arch_atomic64_dec(v);
}

static __always_inline void atomic_add(int i, atomic_t *v)
{
	kasan_check_write(v, sizeof(*v));
	arch_atomic_add(i, v);
}

static __always_inline void atomic64_add(s64 i, atomic64_t *v)
{
	kasan_check_write(v, sizeof(*v));
	arch_atomic64_add(i, v);
}

static __always_inline void atomic_sub(int i, atomic_t *v)
{
	kasan_check_write(v, sizeof(*v));
	arch_atomic_sub(i, v);
}

static __always_inline void atomic64_sub(s64 i, atomic64_t *v)
{
	kasan_check_write(v, sizeof(*v));
	arch_atomic64_sub(i, v);
}

static __always_inline void atomic_and(int i, atomic_t *v)
{
	kasan_check_write(v, sizeof(*v));
	arch_atomic_and(i, v);
}

static __always_inline void atomic64_and(s64 i, atomic64_t *v)
{
	kasan_check_write(v, sizeof(*v));
	arch_atomic64_and(i, v);
}

static __always_inline void atomic_or(int i, atomic_t *v)
{
	kasan_check_write(v, sizeof(*v));
	arch_atomic_or(i, v);
}

static __always_inline void atomic64_or(s64 i, atomic64_t *v)
{
	kasan_check_write(v, sizeof(*v));
	arch_atomic64_or(i, v);
}

static __always_inline void atomic_xor(int i, atomic_t *v)
{
	kasan_check_write(v, sizeof(*v));
	arch_atomic_xor(i, v);
}

static __always_inline void atomic64_xor(s64 i, atomic64_t *v)
{
	kasan_check_write(v, sizeof(*v));
	arch_atomic64_xor(i, v);
}

static __always_inline int atomic_inc_return(atomic_t *v)
{
	kasan_check_write(v, sizeof(*v));
	return arch_atomic_inc_return(v);
}

static __always_inline s64 atomic64_inc_return(atomic64_t *v)
{
	kasan_check_write(v, sizeof(*v));
	return arch_atomic64_inc_return(v);
}

static __always_inline int atomic_dec_return(atomic_t *v)
{
	kasan_check_write(v, sizeof(*v));
	return arch_atomic_dec_return(v);
}

static __always_inline s64 atomic64_dec_return(atomic64_t *v)
{
	kasan_check_write(v, sizeof(*v));
	return arch_atomic64_dec_return(v);
}

static __always_inline s64 atomic64_inc_not_zero(atomic64_t *v)
{
	kasan_check_write(v, sizeof(*v));
	return arch_atomic64_inc_not_zero(v);
}

static __always_inline s64 atomic64_dec_if_positive(atomic64_t *v)
{
	kasan_check_write(v, sizeof(*v));
	return arch_atomic64_dec_if_positive(v);
}

static __always_inline bool atomic_dec_and_test(atomic_t *v)
{
	kasan_check_write(v, sizeof(*v));
	return arch_atomic_dec_and_test(v);
}

static __always_inline bool atomic64_dec_and_test(atomic64_t *v)
{
	kasan_check_write(v, sizeof(*v));
	return arch_atomic64_dec_and_test(v);
}

static __always_inline bool atomic_inc_and_test(atomic_t *v)
{
	kasan_check_write(v, sizeof(*v));
	return arch_atomic_inc_and_test(v);
}

static __always_inline bool atomic64_inc_and_test(atomic64_t *v)
{
	kasan_check_write(v, sizeof(*v));
	return arch_atomic64_inc_and_test(v);
}

static __always_inline int atomic_add_return(int i, atomic_t *v)
{
	kasan_check_write(v, sizeof(*v));
	return arch_atomic_add_return(i, v);
}

static __always_inline s64 atomic64_add_return(s64 i, atomic64_t *v)
{
	kasan_check_write(v, sizeof(*v));
	return arch_atomic64_add_return(i, v);
}

static __always_inline int atomic_sub_return(int i, atomic_t *v)
{
	kasan_check_write(v, sizeof(*v));
	return arch_atomic_sub_return(i, v);
}

static __always_inline s64 atomic64_sub_return(s64 i, atomic64_t *v)
{
	kasan_check_write(v, sizeof(*v));
	return arch_atomic64_sub_return(i, v);
}

static __always_inline int atomic_fetch_add(int i, atomic_t *v)
{
	kasan_check_write(v, sizeof(*v));
	return arch_atomic_fetch_add(i, v);
}

static __always_inline s64 atomic64_fetch_add(s64 i, atomic64_t *v)
{
	kasan_check_write(v, sizeof(*v));
	return arch_atomic64_fetch_add(i, v);
}

static __always_inline int atomic_fetch_sub(int i, atomic_t *v)
{
	kasan_check_write(v, sizeof(*v));
	return arch_atomic_fetch_sub(i, v);
}

static __always_inline s64 atomic64_fetch_sub(s64 i, atomic64_t *v)
{
	kasan_check_write(v, sizeof(*v));
	return arch_atomic64_fetch_sub(i, v);
}

static __always_inline int atomic_fetch_and(int i, atomic_t *v)
{
	kasan_check_write(v, sizeof(*v));
	return arch_atomic_fetch_and(i, v);
}

static __always_inline s64 atomic64_fetch_and(s64 i, atomic64_t *v)
{
	kasan_check_write(v, sizeof(*v));
	return arch_atomic64_fetch_and(i, v);
}

static __always_inline int atomic_fetch_or(int i, atomic_t *v)
{
	kasan_check_write(v, sizeof(*v));
	return arch_atomic_fetch_or(i, v);
}

static __always_inline s64 atomic64_fetch_or(s64 i, atomic64_t *v)
{
	kasan_check_write(v, sizeof(*v));
	return arch_atomic64_fetch_or(i, v);
}

static __always_inline int atomic_fetch_xor(int i, atomic_t *v)
{
	kasan_check_write(v, sizeof(*v));
	return arch_atomic_fetch_xor(i, v);
}

static __always_inline s64 atomic64_fetch_xor(s64 i, atomic64_t *v)
{
	kasan_check_write(v, sizeof(*v));
	return arch_atomic64_fetch_xor(i, v);
}

static __always_inline bool atomic_sub_and_test(int i, atomic_t *v)
{
	kasan_check_write(v, sizeof(*v));
	return arch_atomic_sub_and_test(i, v);
}

static __always_inline bool atomic64_sub_and_test(s64 i, atomic64_t *v)
{
	kasan_check_write(v, sizeof(*v));
	return arch_atomic64_sub_and_test(i, v);
}

static __always_inline bool atomic_add_negative(int i, atomic_t *v)
{
	kasan_check_write(v, sizeof(*v));
	return arch_atomic_add_negative(i, v);
}

static __always_inline bool atomic64_add_negative(s64 i, atomic64_t *v)
{
	kasan_check_write(v, sizeof(*v));
	return arch_atomic64_add_negative(i, v);
}

static __always_inline unsigned long
cmpxchg_size(volatile void *ptr, unsigned long old, unsigned long new, int size)
{
	kasan_check_write(ptr, size);
	switch (size) {
	case 1:
		return arch_cmpxchg((u8 *)ptr, (u8)old, (u8)new);
	case 2:
		return arch_cmpxchg((u16 *)ptr, (u16)old, (u16)new);
	case 4:
		return arch_cmpxchg((u32 *)ptr, (u32)old, (u32)new);
	case 8:
		BUILD_BUG_ON(sizeof(unsigned long) != 8);
		return arch_cmpxchg((u64 *)ptr, (u64)old, (u64)new);
	}
	BUILD_BUG();
	return 0;
}

#define cmpxchg(ptr, old, new)						\
({									\
	((__typeof__(*(ptr)))cmpxchg_size((ptr), (unsigned long)(old),	\
		(unsigned long)(new), sizeof(*(ptr))));			\
})

static __always_inline unsigned long
sync_cmpxchg_size(volatile void *ptr, unsigned long old, unsigned long new,
		  int size)
{
	kasan_check_write(ptr, size);
	switch (size) {
	case 1:
		return arch_sync_cmpxchg((u8 *)ptr, (u8)old, (u8)new);
	case 2:
		return arch_sync_cmpxchg((u16 *)ptr, (u16)old, (u16)new);
	case 4:
		return arch_sync_cmpxchg((u32 *)ptr, (u32)old, (u32)new);
	case 8:
		BUILD_BUG_ON(sizeof(unsigned long) != 8);
		return arch_sync_cmpxchg((u64 *)ptr, (u64)old, (u64)new);
	}
	BUILD_BUG();
	return 0;
}

#define sync_cmpxchg(ptr, old, new)					\
({									\
	((__typeof__(*(ptr)))sync_cmpxchg_size((ptr),			\
		(unsigned long)(old), (unsigned long)(new),		\
		sizeof(*(ptr))));					\
})

static __always_inline unsigned long
cmpxchg_local_size(volatile void *ptr, unsigned long old, unsigned long new,
		   int size)
{
	kasan_check_write(ptr, size);
	switch (size) {
	case 1:
		return arch_cmpxchg_local((u8 *)ptr, (u8)old, (u8)new);
	case 2:
		return arch_cmpxchg_local((u16 *)ptr, (u16)old, (u16)new);
	case 4:
		return arch_cmpxchg_local((u32 *)ptr, (u32)old, (u32)new);
	case 8:
		BUILD_BUG_ON(sizeof(unsigned long) != 8);
		return arch_cmpxchg_local((u64 *)ptr, (u64)old, (u64)new);
	}
	BUILD_BUG();
	return 0;
}

#define cmpxchg_local(ptr, old, new)					\
({									\
	((__typeof__(*(ptr)))cmpxchg_local_size((ptr),			\
		(unsigned long)(old), (unsigned long)(new),		\
		sizeof(*(ptr))));					\
})

static __always_inline u64
cmpxchg64_size(volatile u64 *ptr, u64 old, u64 new)
{
	kasan_check_write(ptr, sizeof(*ptr));
	return arch_cmpxchg64(ptr, old, new);
}

#define cmpxchg64(ptr, old, new)					\
({									\
	((__typeof__(*(ptr)))cmpxchg64_size((ptr), (u64)(old),		\
		(u64)(new)));						\
})

static __always_inline u64
cmpxchg64_local_size(volatile u64 *ptr, u64 old, u64 new)
{
	kasan_check_write(ptr, sizeof(*ptr));
	return arch_cmpxchg64_local(ptr, old, new);
}

#define cmpxchg64_local(ptr, old, new)					\
({									\
	((__typeof__(*(ptr)))cmpxchg64_local_size((ptr), (u64)(old),	\
		(u64)(new)));						\
})

/*
 * Originally we had the following code here:
 *     __typeof__(p1) ____p1 = (p1);
 *     kasan_check_write(____p1, 2 * sizeof(*____p1));
 *     arch_cmpxchg_double(____p1, (p2), (o1), (o2), (n1), (n2));
 * But it leads to compilation failures (see gcc issue 72873).
 * So for now it's left non-instrumented.
 * There are few callers of cmpxchg_double(), so it's not critical.
 */
#define cmpxchg_double(p1, p2, o1, o2, n1, n2)				\
({									\
	arch_cmpxchg_double((p1), (p2), (o1), (o2), (n1), (n2));	\
})

#define cmpxchg_double_local(p1, p2, o1, o2, n1, n2)			\
({									\
	arch_cmpxchg_double_local((p1), (p2), (o1), (o2), (n1), (n2));	\
})

#endif /* _LINUX_ATOMIC_INSTRUMENTED_H */