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#ifndef _ASM_X86_UACCESS_H

#define _ASM_X86_UACCESS_H

/*

 * User space memory access functions

 */

#include 

#include 

#include 

#include 

#include 

#include 

#include 

#define VERIFY_READ 0

#define VERIFY_WRITE 1

/*

 * The fs value determines whether argument validity checking should be

 * performed or not.  If get_fs() == USER_DS, checking is performed, with

 * get_fs() == KERNEL_DS, checking is bypassed.

 *

 * For historical reasons, these macros are grossly misnamed.

 */

#define MAKE_MM_SEG(s)	((mm_segment_t) { (s) })

#define KERNEL_DS	MAKE_MM_SEG(-1UL)

#define USER_DS 	MAKE_MM_SEG(TASK_SIZE_MAX)

#define get_ds()	(KERNEL_DS)

#define get_fs()	(current_thread_info()->addr_limit)

#define set_fs(x)	(current_thread_info()->addr_limit = (x))

#define segment_eq(a, b)	((a).seg == (b).seg)

#define user_addr_max() (current_thread_info()->addr_limit.seg)

#define __addr_ok(addr) 	\

	((unsigned long __force)(addr) < user_addr_max())

/*

 * Test whether a block of memory is a valid user space address.

 * Returns 0 if the range is valid, nonzero otherwise.

 */

static inline bool __chk_range_not_ok(unsigned long addr, unsigned long size, unsigned long limit)

{

	/*

	 * If we have used "sizeof()" for the size,

	 * we know it won't overflow the limit (but

	 * it might overflow the 'addr', so it's

	 * important to subtract the size from the

	 * limit, not add it to the address).

	 */

	if (__builtin_constant_p(size))

		return unlikely(addr > limit - size);

	/* Arbitrary sizes? Be careful about overflow */

	addr += size;

	if (unlikely(addr < size))

		return true;

	return unlikely(addr > limit);

}

#define __range_not_ok(addr, size, limit)				\

({									\

	__chk_user_ptr(addr);						\

	__chk_range_not_ok((unsigned long __force)(addr), size, limit); \

})

/**

 * access_ok: - Checks if a user space pointer is valid

 * @type: Type of access: %VERIFY_READ or %VERIFY_WRITE.  Note that

 *        %VERIFY_WRITE is a superset of %VERIFY_READ - if it is safe

 *        to write to a block, it is always safe to read from it.

 * @addr: User space pointer to start of block to check

 * @size: Size of block to check

 *

 * Context: User context only. This function may sleep if pagefaults are

 *          enabled.

 *

 * Checks if a pointer to a block of memory in user space is valid.

 *

 * Returns true (nonzero) if the memory block may be valid, false (zero)

 * if it is definitely invalid.

 *

 * Note that, depending on architecture, this function probably just

 * checks that the pointer is in the user space range - after calling

 * this function, memory access functions may still return -EFAULT.

 */

#define access_ok(type, addr, size) \

	likely(!__range_not_ok(addr, size, user_addr_max()))

/*

 * The exception table consists of triples of addresses relative to the

 * exception table entry itself. The first address is of an instruction

 * that is allowed to fault, the second is the target at which the program

 * should continue. The third is a handler function to deal with the fault

 * caused by the instruction in the first field.

 *

 * All the routines below use bits of fixup code that are out of line

 * with the main instruction path.  This means when everything is well,

 * we don't even have to jump over them.  Further, they do not intrude

 * on our cache or tlb entries.

 */

struct exception_table_entry {

	int insn, fixup, handler;

};

#define ARCH_HAS_RELATIVE_EXTABLE

#define swap_ex_entry_fixup(a, b, tmp, delta)			\

	do {							\

		(a)->fixup = (b)->fixup + (delta);		\

		(b)->fixup = (tmp).fixup - (delta);		\

		(a)->handler = (b)->handler + (delta);		\

		(b)->handler = (tmp).handler - (delta);		\

	} while (0)

extern int fixup_exception(struct pt_regs *regs, int trapnr);

extern bool ex_has_fault_handler(unsigned long ip);

extern int early_fixup_exception(unsigned long *ip);

/*

 * These are the main single-value transfer routines.  They automatically

 * use the right size if we just have the right pointer type.

 *

 * This gets kind of ugly. We want to return _two_ values in "get_user()"

 * and yet we don't want to do any pointers, because that is too much

 * of a performance impact. Thus we have a few rather ugly macros here,

 * and hide all the ugliness from the user.

 *

 * The "__xxx" versions of the user access functions are versions that

 * do not verify the address space, that must have been done previously

 * with a separate "access_ok()" call (this is used when we do multiple

 * accesses to the same area of user memory).

 */

extern int __get_user_1(void);

extern int __get_user_2(void);

extern int __get_user_4(void);

extern int __get_user_8(void);

extern int __get_user_bad(void);

#define __uaccess_begin() stac()

#define __uaccess_end()   clac()

/*

 * This is a type: either unsigned long, if the argument fits into

 * that type, or otherwise unsigned long long.

 */

#define __inttype(x) \

__typeof__(__builtin_choose_expr(sizeof(x) > sizeof(0UL), 0ULL, 0UL))

/**

 * get_user: - Get a simple variable from user space.

 * @x:   Variable to store result.

 * @ptr: Source address, in user space.

 *

 * Context: User context only. This function may sleep if pagefaults are

 *          enabled.

 *

 * This macro copies a single simple variable from user space to kernel

 * space.  It supports simple types like char and int, but not larger

 * data types like structures or arrays.

 *

 * @ptr must have pointer-to-simple-variable type, and the result of

 * dereferencing @ptr must be assignable to @x without a cast.

 *

 * Returns zero on success, or -EFAULT on error.

 * On error, the variable @x is set to zero.

 */

/*

 * Careful: we have to cast the result to the type of the pointer

 * for sign reasons.

 *

 * The use of _ASM_DX as the register specifier is a bit of a

 * simplification, as gcc only cares about it as the starting point

 * and not size: for a 64-bit value it will use %ecx:%edx on 32 bits

 * (%ecx being the next register in gcc's x86 register sequence), and

 * %rdx on 64 bits.

 *

 * Clang/LLVM cares about the size of the register, but still wants

 * the base register for something that ends up being a pair.

 */

#define get_user(x, ptr)						\

({									\

	int __ret_gu;							\

	register __inttype(*(ptr)) __val_gu asm("%"_ASM_DX);		\

	register void *__sp asm(_ASM_SP);				\

	__chk_user_ptr(ptr);						\

	might_fault();							\

	asm volatile("call __get_user_%P4"				\

		     : "=a" (__ret_gu), "=r" (__val_gu), "+r" (__sp)	\

		     : "0" (ptr), "i" (sizeof(*(ptr))));		\

	(x) = (__force __typeof__(*(ptr))) __val_gu;			\

	__builtin_expect(__ret_gu, 0);					\

})

#define __put_user_x(size, x, ptr, __ret_pu)			\

	asm volatile("call __put_user_" #size : "=a" (__ret_pu)	\

		     : "0" ((typeof(*(ptr)))(x)), "c" (ptr) : "ebx")

#ifdef CONFIG_X86_32

#define __put_user_asm_u64(x, addr, err, errret)			\

	asm volatile("\n"						\

		     "1:	movl %%eax,0(%2)\n"			\

		     "2:	movl %%edx,4(%2)\n"			\

		     "3:"						\

		     ".section .fixup,\"ax\"\n"				\

		     "4:	movl %3,%0\n"				\

		     "	jmp 3b\n"					\

		     ".previous\n"					\

		     _ASM_EXTABLE(1b, 4b)				\

		     _ASM_EXTABLE(2b, 4b)				\

		     : "=r" (err)					\

		     : "A" (x), "r" (addr), "i" (errret), "0" (err))

#define __put_user_asm_ex_u64(x, addr)					\

	asm volatile("\n"						\

		     "1:	movl %%eax,0(%1)\n"			\

		     "2:	movl %%edx,4(%1)\n"			\

		     "3:"						\

		     _ASM_EXTABLE_EX(1b, 2b)				\

		     _ASM_EXTABLE_EX(2b, 3b)				\

		     : : "A" (x), "r" (addr))

#define __put_user_x8(x, ptr, __ret_pu)				\

	asm volatile("call __put_user_8" : "=a" (__ret_pu)	\

		     : "A" ((typeof(*(ptr)))(x)), "c" (ptr) : "ebx")

#else

#define __put_user_asm_u64(x, ptr, retval, errret) \

	__put_user_asm(x, ptr, retval, "q", "", "er", errret)

#define __put_user_asm_ex_u64(x, addr)	\

	__put_user_asm_ex(x, addr, "q", "", "er")

#define __put_user_x8(x, ptr, __ret_pu) __put_user_x(8, x, ptr, __ret_pu)

#endif

extern void __put_user_bad(void);

/*

 * Strange magic calling convention: pointer in %ecx,

 * value in %eax(:%edx), return value in %eax. clobbers %rbx

 */

extern void __put_user_1(void);

extern void __put_user_2(void);

extern void __put_user_4(void);

extern void __put_user_8(void);

/**

 * put_user: - Write a simple value into user space.

 * @x:   Value to copy to user space.

 * @ptr: Destination address, in user space.

 *

 * Context: User context only. This function may sleep if pagefaults are

 *          enabled.

 *

 * This macro copies a single simple value from kernel space to user

 * space.  It supports simple types like char and int, but not larger

 * data types like structures or arrays.

 *

 * @ptr must have pointer-to-simple-variable type, and @x must be assignable

 * to the result of dereferencing @ptr.

 *

 * Returns zero on success, or -EFAULT on error.

 */

#define put_user(x, ptr)					\

({								\

	int __ret_pu;						\

	__typeof__(*(ptr)) __pu_val;				\

	__chk_user_ptr(ptr);					\

	might_fault();						\

	__pu_val = x;						\

	switch (sizeof(*(ptr))) {				\

	case 1:							\

		__put_user_x(1, __pu_val, ptr, __ret_pu);	\

		break;						\

	case 2:							\

		__put_user_x(2, __pu_val, ptr, __ret_pu);	\

		break;						\

	case 4:							\

		__put_user_x(4, __pu_val, ptr, __ret_pu);	\

		break;						\

	case 8:							\

		__put_user_x8(__pu_val, ptr, __ret_pu);		\

		break;						\

	default:						\

		__put_user_x(X, __pu_val, ptr, __ret_pu);	\

		break;						\

	}							\

	__builtin_expect(__ret_pu, 0);				\

})

#define __put_user_size(x, ptr, size, retval, errret)			\

do {									\

	retval = 0;							\

	__chk_user_ptr(ptr);						\

	switch (size) {							\

	case 1:								\

		__put_user_asm(x, ptr, retval, "b", "b", "iq", errret);	\

		break;							\

	case 2:								\

		__put_user_asm(x, ptr, retval, "w", "w", "ir", errret);	\

		break;							\

	case 4:								\

		__put_user_asm(x, ptr, retval, "l", "k", "ir", errret);	\

		break;							\

	case 8:								\

		__put_user_asm_u64((__typeof__(*ptr))(x), ptr, retval,	\

				   errret);				\

		break;							\

	default:							\

		__put_user_bad();					\

	}								\

} while (0)

/*

 * This doesn't do __uaccess_begin/end - the exception handling

 * around it must do that.

 */

#define __put_user_size_ex(x, ptr, size)				\

do {									\

	__chk_user_ptr(ptr);						\

	switch (size) {							\

	case 1:								\

		__put_user_asm_ex(x, ptr, "b", "b", "iq");		\

		break;							\

	case 2:								\

		__put_user_asm_ex(x, ptr, "w", "w", "ir");		\

		break;							\

	case 4:								\

		__put_user_asm_ex(x, ptr, "l", "k", "ir");		\

		break;							\

	case 8:								\

		__put_user_asm_ex_u64((__typeof__(*ptr))(x), ptr);	\

		break;							\

	default:							\

		__put_user_bad();					\

	}								\

} while (0)

#ifdef CONFIG_X86_32

#define __get_user_asm_u64(x, ptr, retval, errret)	(x) = __get_user_bad()

#define __get_user_asm_ex_u64(x, ptr)			(x) = __get_user_bad()

#else

#define __get_user_asm_u64(x, ptr, retval, errret) \

	 __get_user_asm(x, ptr, retval, "q", "", "=r", errret)

#define __get_user_asm_ex_u64(x, ptr) \

	 __get_user_asm_ex(x, ptr, "q", "", "=r")

#endif

#define __get_user_size(x, ptr, size, retval, errret)			\

do {									\

	retval = 0;							\

	__chk_user_ptr(ptr);						\

	switch (size) {							\

	case 1:								\

		__get_user_asm(x, ptr, retval, "b", "b", "=q", errret);	\

		break;							\

	case 2:								\

		__get_user_asm(x, ptr, retval, "w", "w", "=r", errret);	\

		break;							\

	case 4:								\

		__get_user_asm(x, ptr, retval, "l", "k", "=r", errret);	\

		break;							\

	case 8:								\

		__get_user_asm_u64(x, ptr, retval, errret);		\

		break;							\

	default:							\

		(x) = __get_user_bad();					\

	}								\

} while (0)

#define __get_user_asm(x, addr, err, itype, rtype, ltype, errret)	\

	asm volatile("\n"						\

		     "1:	mov"itype" %2,%"rtype"1\n"		\

		     "2:\n"						\

		     ".section .fixup,\"ax\"\n"				\

		     "3:	mov %3,%0\n"				\

		     "	xor"itype" %"rtype"1,%"rtype"1\n"		\

		     "	jmp 2b\n"					\

		     ".previous\n"					\

		     _ASM_EXTABLE(1b, 3b)				\

		     : "=r" (err), ltype(x)				\

		     : "m" (__m(addr)), "i" (errret), "0" (err))

/*

 * This doesn't do __uaccess_begin/end - the exception handling

 * around it must do that.

 */

#define __get_user_size_ex(x, ptr, size)				\

do {									\

	__chk_user_ptr(ptr);						\

	switch (size) {							\

	case 1:								\

		__get_user_asm_ex(x, ptr, "b", "b", "=q");		\

		break;							\

	case 2:								\

		__get_user_asm_ex(x, ptr, "w", "w", "=r");		\

		break;							\

	case 4:								\

		__get_user_asm_ex(x, ptr, "l", "k", "=r");		\

		break;							\

	case 8:								\

		__get_user_asm_ex_u64(x, ptr);				\

		break;							\

	default:							\

		(x) = __get_user_bad();					\

	}								\

} while (0)

#define __get_user_asm_ex(x, addr, itype, rtype, ltype)			\

	asm volatile("1:	mov"itype" %1,%"rtype"0\n"		\

		     "2:\n"						\

		     _ASM_EXTABLE_EX(1b, 2b)				\

		     : ltype(x) : "m" (__m(addr)))

#define __put_user_nocheck(x, ptr, size)			\

({								\

	int __pu_err;						\

	__uaccess_begin();					\

	__put_user_size((x), (ptr), (size), __pu_err, -EFAULT);	\

	__uaccess_end();					\

	__builtin_expect(__pu_err, 0);				\

})

#define __get_user_nocheck(x, ptr, size)				\

({									\

	int __gu_err;							\

	unsigned long __gu_val;						\

	__uaccess_begin();						\

	__get_user_size(__gu_val, (ptr), (size), __gu_err, -EFAULT);	\

	__uaccess_end();						\

	(x) = (__force __typeof__(*(ptr)))__gu_val;			\

	__builtin_expect(__gu_err, 0);					\

})

/* FIXME: this hack is definitely wrong -AK */

struct __large_struct { unsigned long buf[100]; };

#define __m(x) (*(struct __large_struct __user *)(x))

/*

 * Tell gcc we read from memory instead of writing: this is because

 * we do not write to any memory gcc knows about, so there are no

 * aliasing issues.

 */

#define __put_user_asm(x, addr, err, itype, rtype, ltype, errret)	\

	asm volatile("\n"						\

		     "1:	mov"itype" %"rtype"1,%2\n"		\

		     "2:\n"						\

		     ".section .fixup,\"ax\"\n"				\

		     "3:	mov %3,%0\n"				\

		     "	jmp 2b\n"					\

		     ".previous\n"					\

		     _ASM_EXTABLE(1b, 3b)				\

		     : "=r"(err)					\

		     : ltype(x), "m" (__m(addr)), "i" (errret), "0" (err))

#define __put_user_asm_ex(x, addr, itype, rtype, ltype)			\

	asm volatile("1:	mov"itype" %"rtype"0,%1\n"		\

		     "2:\n"						\

		     _ASM_EXTABLE_EX(1b, 2b)				\

		     : : ltype(x), "m" (__m(addr)))

/*

 * uaccess_try and catch

 */

#define uaccess_try	do {						\

	current_thread_info()->uaccess_err = 0;				\

	__uaccess_begin();						\

	barrier();

#define uaccess_catch(err)						\

	__uaccess_end();						\

	(err) |= (current_thread_info()->uaccess_err ? -EFAULT : 0);	\

} while (0)

/**

 * __get_user: - Get a simple variable from user space, with less checking.

 * @x:   Variable to store result.

 * @ptr: Source address, in user space.

 *

 * Context: User context only. This function may sleep if pagefaults are

 *          enabled.

 *

 * This macro copies a single simple variable from user space to kernel

 * space.  It supports simple types like char and int, but not larger

 * data types like structures or arrays.

 *

 * @ptr must have pointer-to-simple-variable type, and the result of

 * dereferencing @ptr must be assignable to @x without a cast.

 *

 * Caller must check the pointer with access_ok() before calling this

 * function.

 *

 * Returns zero on success, or -EFAULT on error.

 * On error, the variable @x is set to zero.

 */

#define __get_user(x, ptr)						\

	__get_user_nocheck((x), (ptr), sizeof(*(ptr)))

/**

 * __put_user: - Write a simple value into user space, with less checking.

 * @x:   Value to copy to user space.

 * @ptr: Destination address, in user space.

 *

 * Context: User context only. This function may sleep if pagefaults are

 *          enabled.

 *

 * This macro copies a single simple value from kernel space to user

 * space.  It supports simple types like char and int, but not larger

 * data types like structures or arrays.

 *

 * @ptr must have pointer-to-simple-variable type, and @x must be assignable

 * to the result of dereferencing @ptr.

 *

 * Caller must check the pointer with access_ok() before calling this

 * function.

 *

 * Returns zero on success, or -EFAULT on error.

 */

#define __put_user(x, ptr)						\

	__put_user_nocheck((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr)))

#define __get_user_unaligned __get_user

#define __put_user_unaligned __put_user

/*

 * {get|put}_user_try and catch

 *

 * get_user_try {

 *	get_user_ex(...);

 * } get_user_catch(err)

 */

#define get_user_try		uaccess_try

#define get_user_catch(err)	uaccess_catch(err)

#define get_user_ex(x, ptr)	do {					\

	unsigned long __gue_val;					\

	__get_user_size_ex((__gue_val), (ptr), (sizeof(*(ptr))));	\

	(x) = (__force __typeof__(*(ptr)))__gue_val;			\

} while (0)

#define put_user_try		uaccess_try

#define put_user_catch(err)	uaccess_catch(err)

#define put_user_ex(x, ptr)						\

	__put_user_size_ex((__typeof__(*(ptr)))(x), (ptr), sizeof(*(ptr)))

extern unsigned long

copy_from_user_nmi(void *to, const void __user *from, unsigned long n);

extern __must_check long

strncpy_from_user(char *dst, const char __user *src, long count);

extern __must_check long strlen_user(const char __user *str);

extern __must_check long strnlen_user(const char __user *str, long n);

unsigned long __must_check clear_user(void __user *mem, unsigned long len);

unsigned long __must_check __clear_user(void __user *mem, unsigned long len);

extern void __cmpxchg_wrong_size(void)

	__compiletime_error("Bad argument size for cmpxchg");

#define __user_atomic_cmpxchg_inatomic(uval, ptr, old, new, size)	\

({									\

	int __ret = 0;							\

	__typeof__(ptr) __uval = (uval);				\

	__typeof__(*(ptr)) __old = (old);				\

	__typeof__(*(ptr)) __new = (new);				\

	__uaccess_begin();						\

	switch (size) {							\

	case 1:								\

	{								\

		asm volatile("\n"					\

			"1:\t" LOCK_PREFIX "cmpxchgb %4, %2\n"		\

			"2:\n"						\

			"\t.section .fixup, \"ax\"\n"			\

			"3:\tmov     %3, %0\n"				\

			"\tjmp     2b\n"				\

			"\t.previous\n"					\

			_ASM_EXTABLE(1b, 3b)				\

			: "+r" (__ret), "=a" (__old), "+m" (*(ptr))	\

			: "i" (-EFAULT), "q" (__new), "1" (__old)	\

			: "memory"					\

		);							\

		break;							\

	}								\

	case 2:								\

	{								\

		asm volatile("\n"					\

			"1:\t" LOCK_PREFIX "cmpxchgw %4, %2\n"		\

			"2:\n"						\

			"\t.section .fixup, \"ax\"\n"			\

			"3:\tmov     %3, %0\n"				\

			"\tjmp     2b\n"				\

			"\t.previous\n"					\

			_ASM_EXTABLE(1b, 3b)				\

			: "+r" (__ret), "=a" (__old), "+m" (*(ptr))	\

			: "i" (-EFAULT), "r" (__new), "1" (__old)	\

			: "memory"					\

		);							\

		break;							\

	}								\

	case 4:								\

	{								\

		asm volatile("\n"					\

			"1:\t" LOCK_PREFIX "cmpxchgl %4, %2\n"		\

			"2:\n"						\

			"\t.section .fixup, \"ax\"\n"			\

			"3:\tmov     %3, %0\n"				\

			"\tjmp     2b\n"				\

			"\t.previous\n"					\

			_ASM_EXTABLE(1b, 3b)				\

			: "+r" (__ret), "=a" (__old), "+m" (*(ptr))	\

			: "i" (-EFAULT), "r" (__new), "1" (__old)	\

			: "memory"					\

		);							\

		break;							\

	}								\

	case 8:								\

	{								\

		if (!IS_ENABLED(CONFIG_X86_64))				\

			__cmpxchg_wrong_size();				\

									\

		asm volatile("\n"					\

			"1:\t" LOCK_PREFIX "cmpxchgq %4, %2\n"		\

			"2:\n"						\

			"\t.section .fixup, \"ax\"\n"			\

			"3:\tmov     %3, %0\n"				\

			"\tjmp     2b\n"				\

			"\t.previous\n"					\

			_ASM_EXTABLE(1b, 3b)				\

			: "+r" (__ret), "=a" (__old), "+m" (*(ptr))	\

			: "i" (-EFAULT), "r" (__new), "1" (__old)	\

			: "memory"					\

		);							\

		break;							\

	}								\

	default:							\

		__cmpxchg_wrong_size();					\

	}								\

	__uaccess_end();						\

	*__uval = __old;						\

	__ret;								\

})

#define user_atomic_cmpxchg_inatomic(uval, ptr, old, new)		\

({									\

	access_ok(VERIFY_WRITE, (ptr), sizeof(*(ptr))) ?		\

		__user_atomic_cmpxchg_inatomic((uval), (ptr),		\

				(old), (new), sizeof(*(ptr))) :		\

		-EFAULT;						\

})

/*

 * movsl can be slow when source and dest are not both 8-byte aligned

 */

#ifdef CONFIG_X86_INTEL_USERCOPY

extern struct movsl_mask {

	int mask;

} ____cacheline_aligned_in_smp movsl_mask;

#endif

#define ARCH_HAS_NOCACHE_UACCESS 1

#ifdef CONFIG_X86_32

# include 

#else

# include 

#endif

unsigned long __must_check _copy_from_user(void *to, const void __user *from,

					   unsigned n);

unsigned long __must_check _copy_to_user(void __user *to, const void *from,

					 unsigned n);

#ifdef CONFIG_DEBUG_STRICT_USER_COPY_CHECKS

# define copy_user_diag __compiletime_error

#else

# define copy_user_diag __compiletime_warning

#endif

extern void copy_user_diag("copy_from_user() buffer size is too small")

copy_from_user_overflow(void);

extern void copy_user_diag("copy_to_user() buffer size is too small")

copy_to_user_overflow(void) __asm__("copy_from_user_overflow");

#undef copy_user_diag

#ifdef CONFIG_DEBUG_STRICT_USER_COPY_CHECKS

extern void

__compiletime_warning("copy_from_user() buffer size is not provably correct")

__copy_from_user_overflow(void) __asm__("copy_from_user_overflow");

#define __copy_from_user_overflow(size, count) __copy_from_user_overflow()

extern void

__compiletime_warning("copy_to_user() buffer size is not provably correct")

__copy_to_user_overflow(void) __asm__("copy_from_user_overflow");

#define __copy_to_user_overflow(size, count) __copy_to_user_overflow()

#else

static inline void

__copy_from_user_overflow(int size, unsigned long count)

{

	WARN(1, "Buffer overflow detected (%d < %lu)!\n", size, count);

}

#define __copy_to_user_overflow __copy_from_user_overflow

#endif

static inline unsigned long __must_check

copy_from_user(void *to, const void __user *from, unsigned long n)

{

	int sz = __compiletime_object_size(to);

	might_fault();

	/*

	 * While we would like to have the compiler do the checking for us

	 * even in the non-constant size case, any false positives there are

	 * a problem (especially when DEBUG_STRICT_USER_COPY_CHECKS, but even

	 * without - the [hopefully] dangerous looking nature of the warning

	 * would make people go look at the respecitive call sites over and

	 * over again just to find that there's no problem).

	 *

	 * And there are cases where it's just not realistic for the compiler

	 * to prove the count to be in range. For example when multiple call

	 * sites of a helper function - perhaps in different source files -

	 * all doing proper range checking, yet the helper function not doing

	 * so again.

	 *

	 * Therefore limit the compile time checking to the constant size

	 * case, and do only runtime checking for non-constant sizes.

	 */

	if (likely(sz < 0 || sz >= n))

		n = _copy_from_user(to, from, n);

	else if(__builtin_constant_p(n))

		copy_from_user_overflow();

	else

		__copy_from_user_overflow(sz, n);

	return n;

}

static inline unsigned long __must_check

copy_to_user(void __user *to, const void *from, unsigned long n)

{

	int sz = __compiletime_object_size(from);

	might_fault();

	/* See the comment in copy_from_user() above. */

	if (likely(sz < 0 || sz >= n))

		n = _copy_to_user(to, from, n);

	else if(__builtin_constant_p(n))

		copy_to_user_overflow();

	else

		__copy_to_user_overflow(sz, n);

	return n;

}

#undef __copy_from_user_overflow

#undef __copy_to_user_overflow

/*

 * We rely on the nested NMI work to allow atomic faults from the NMI path; the

 * nested NMI paths are careful to preserve CR2.

 *

 * Caller must use pagefault_enable/disable, or run in interrupt context,

 * and also do a uaccess_ok() check

 */

#define __copy_from_user_nmi __copy_from_user_inatomic

/*

 * The "unsafe" user accesses aren't really "unsafe", but the naming

 * is a big fat warning: you have to not only do the access_ok()

 * checking before using them, but you have to surround them with the

 * user_access_begin/end() pair.

 */

#define user_access_begin()	__uaccess_begin()

#define user_access_end()	__uaccess_end()

#define unsafe_put_user(x, ptr)						\

({										\

	int __pu_err;								\

	__put_user_size((x), (ptr), sizeof(*(ptr)), __pu_err, -EFAULT);		\

	__builtin_expect(__pu_err, 0);						\

})

#define unsafe_get_user(x, ptr)						\

({										\

	int __gu_err;								\

	unsigned long __gu_val;							\

	__get_user_size(__gu_val, (ptr), sizeof(*(ptr)), __gu_err, -EFAULT);	\

	(x) = (__force __typeof__(*(ptr)))__gu_val;				\

	__builtin_expect(__gu_err, 0);						\

})

#endif /* _ASM_X86_UACCESS_H */