cregit-Linux how code gets into the kernel

Release 4.8 arch/sh/include/asm/uaccess.h

#ifndef __ASM_SH_UACCESS_H

#define __ASM_SH_UACCESS_H

#include <linux/errno.h>
#include <linux/sched.h>
#include <asm/segment.h>


#define VERIFY_READ    0

#define VERIFY_WRITE   1


#define __addr_ok(addr) \
	((unsigned long __force)(addr) < current_thread_info()->addr_limit.seg)

/*
 * __access_ok: Check if address with size is OK or not.
 *
 * Uhhuh, this needs 33-bit arithmetic. We have a carry..
 *
 * sum := addr + size;  carry? --> flag = true;
 * if (sum >= addr_limit) flag = true;
 */

#define __access_ok(addr, size)		\
	(__addr_ok((addr) + (size)))

#define access_ok(type, addr, size)	\
	(__chk_user_ptr(addr),          \
         __access_ok((unsigned long __force)(addr), (size)))


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

/*
 * Uh, these should become the main single-value transfer routines ...
 * They automatically use the right size if we just have the right
 * pointer type ...
 *
 * As SuperH uses the same address space for kernel and user data, we
 * can just do these as direct assignments.
 *
 * Careful to not
 * (a) re-use the arguments for side effects (sizeof is ok)
 * (b) require any knowledge of processes at this stage
 */

#define put_user(x,ptr)		__put_user_check((x), (ptr), sizeof(*(ptr)))

#define get_user(x,ptr)		__get_user_check((x), (ptr), sizeof(*(ptr)))

/*
 * The "__xxx" versions do not do address space checking, useful when
 * doing multiple accesses to the same area (the user has to do the
 * checks by hand with "access_ok()")
 */

#define __put_user(x,ptr)	__put_user_nocheck((x), (ptr), sizeof(*(ptr)))

#define __get_user(x,ptr)	__get_user_nocheck((x), (ptr), sizeof(*(ptr)))



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

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


#define __get_user_nocheck(x,ptr,size)				\
({                                                              \
        long __gu_err;                                          \
        unsigned long __gu_val;                                 \
        const __typeof__(*(ptr)) __user *__gu_addr = (ptr);     \
        __chk_user_ptr(ptr);                                    \
        __get_user_size(__gu_val, __gu_addr, (size), __gu_err); \
        (x) = (__force __typeof__(*(ptr)))__gu_val;             \
        __gu_err;                                               \
})


#define __get_user_check(x,ptr,size)					\
({                                                                      \
        long __gu_err = -EFAULT;                                        \
        unsigned long __gu_val = 0;                                     \
        const __typeof__(*(ptr)) *__gu_addr = (ptr);                    \
        if (likely(access_ok(VERIFY_READ, __gu_addr, (size))))          \
                __get_user_size(__gu_val, __gu_addr, (size), __gu_err); \
        (x) = (__force __typeof__(*(ptr)))__gu_val;                     \
        __gu_err;                                                       \
})


#define __put_user_nocheck(x,ptr,size)				\
({                                                              \
        long __pu_err;                                          \
        __typeof__(*(ptr)) __user *__pu_addr = (ptr);           \
        __typeof__(*(ptr)) __pu_val = x;                        \
        __chk_user_ptr(ptr);                                    \
        __put_user_size(__pu_val, __pu_addr, (size), __pu_err); \
        __pu_err;                                               \
})


#define __put_user_check(x,ptr,size)				\
({                                                              \
        long __pu_err = -EFAULT;                                \
        __typeof__(*(ptr)) __user *__pu_addr = (ptr);           \
        __typeof__(*(ptr)) __pu_val = x;                        \
        if (likely(access_ok(VERIFY_WRITE, __pu_addr, size)))   \
                __put_user_size(__pu_val, __pu_addr, (size),    \
                                __pu_err);                      \
        __pu_err;                                               \
})

#ifdef CONFIG_SUPERH32
# include <asm/uaccess_32.h>
#else
# include <asm/uaccess_64.h>
#endif

extern long strncpy_from_user(char *dest, 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);

/* Generic arbitrary sized copy.  */
/* Return the number of bytes NOT copied */
__kernel_size_t __copy_user(void *to, const void *from, __kernel_size_t n);


static __always_inline unsigned long __copy_from_user(void *to, const void __user *from, unsigned long n) { return __copy_user(to, (__force void *)from, n); }

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paul mundtpaul mundt37100.00%1100.00%
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static __always_inline unsigned long __must_check __copy_to_user(void __user *to, const void *from, unsigned long n) { return __copy_user((__force void *)to, from, n); }

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paul mundtpaul mundt38100.00%1100.00%
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#define __copy_to_user_inatomic __copy_to_user #define __copy_from_user_inatomic __copy_from_user /* * Clear the area and return remaining number of bytes * (on failure. Usually it's 0.) */ __kernel_size_t __clear_user(void *addr, __kernel_size_t size); #define clear_user(addr,n) \ ({ \ void __user * __cl_addr = (addr); \ unsigned long __cl_size = (n); \ \ if (__cl_size && access_ok(VERIFY_WRITE, \ ((unsigned long)(__cl_addr)), __cl_size)) \ __cl_size = __clear_user(__cl_addr, __cl_size); \ \ __cl_size; \ })
static inline unsigned long copy_from_user(void *to, const void __user *from, unsigned long n) { unsigned long __copy_from = (unsigned long) from; __kernel_size_t __copy_size = (__kernel_size_t) n; if (__copy_size && __access_ok(__copy_from, __copy_size)) __copy_size = __copy_user(to, from, __copy_size); if (unlikely(__copy_size)) memset(to + (n - __copy_size), 0, __copy_size); return __copy_size; }

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al viroal viro2528.74%150.00%
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static inline unsigned long copy_to_user(void __user *to, const void *from, unsigned long n) { unsigned long __copy_to = (unsigned long) to; __kernel_size_t __copy_size = (__kernel_size_t) n; if (__copy_size && __access_ok(__copy_to, __copy_size)) return __copy_user(to, from, __copy_size); return __copy_size; }

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magnus dammmagnus damm64100.00%1100.00%
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/* * The exception table consists of pairs of addresses: the first is the * address of an instruction that is allowed to fault, and the second is * the address at which the program should continue. No registers are * modified, so it is entirely up to the continuation code to figure out * what to do. * * 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 { unsigned long insn, fixup; }; #if defined(CONFIG_SUPERH64) && defined(CONFIG_MMU) #define ARCH_HAS_SEARCH_EXTABLE #endif int fixup_exception(struct pt_regs *regs); /* Returns 0 if exception not found and fixup.unit otherwise. */ unsigned long search_exception_table(unsigned long addr); const struct exception_table_entry *search_exception_tables(unsigned long addr); extern void *set_exception_table_vec(unsigned int vec, void *handler);
static inline void *set_exception_table_evt(unsigned int evt, void *handler) { return set_exception_table_vec(evt >> 5, handler); }

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david howellsdavid howells26100.00%1100.00%
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struct mem_access { unsigned long (*from)(void *dst, const void __user *src, unsigned long cnt); unsigned long (*to)(void __user *dst, const void *src, unsigned long cnt); }; int handle_unaligned_access(insn_size_t instruction, struct pt_regs *regs, struct mem_access *ma, int, unsigned long address); #endif /* __ASM_SH_UACCESS_H */

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paul mundtpaul mundt38557.55%430.77%
magnus dammmagnus damm13520.18%17.69%
david howellsdavid howells11417.04%215.38%
al viroal viro253.74%17.69%
pre-gitpre-git20.30%17.69%
hirofumi ogawahirofumi ogawa20.30%17.69%
linus torvaldslinus torvalds20.30%17.69%
yoshinori satoyoshinori sato20.30%17.69%
michael s. tsirkinmichael s. tsirkin20.30%17.69%
Total669100.00%13100.00%
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