445 строки
12 KiB
C
445 строки
12 KiB
C
/*
|
|
* linux/include/asm-arm/uaccess.h
|
|
*
|
|
* This program is free software; you can redistribute it and/or modify
|
|
* it under the terms of the GNU General Public License version 2 as
|
|
* published by the Free Software Foundation.
|
|
*/
|
|
#ifndef _ASMARM_UACCESS_H
|
|
#define _ASMARM_UACCESS_H
|
|
|
|
/*
|
|
* User space memory access functions
|
|
*/
|
|
#include <linux/sched.h>
|
|
#include <asm/errno.h>
|
|
#include <asm/memory.h>
|
|
#include <asm/domain.h>
|
|
#include <asm/system.h>
|
|
|
|
#define VERIFY_READ 0
|
|
#define VERIFY_WRITE 1
|
|
|
|
/*
|
|
* 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;
|
|
};
|
|
|
|
extern int fixup_exception(struct pt_regs *regs);
|
|
|
|
/*
|
|
* These two are intentionally not defined anywhere - if the kernel
|
|
* code generates any references to them, that's a bug.
|
|
*/
|
|
extern int __get_user_bad(void);
|
|
extern int __put_user_bad(void);
|
|
|
|
/*
|
|
* Note that this is actually 0x1,0000,0000
|
|
*/
|
|
#define KERNEL_DS 0x00000000
|
|
#define get_ds() (KERNEL_DS)
|
|
|
|
#ifdef CONFIG_MMU
|
|
|
|
#define USER_DS TASK_SIZE
|
|
#define get_fs() (current_thread_info()->addr_limit)
|
|
|
|
static inline void set_fs(mm_segment_t fs)
|
|
{
|
|
current_thread_info()->addr_limit = fs;
|
|
modify_domain(DOMAIN_KERNEL, fs ? DOMAIN_CLIENT : DOMAIN_MANAGER);
|
|
}
|
|
|
|
#define segment_eq(a,b) ((a) == (b))
|
|
|
|
#define __addr_ok(addr) ({ \
|
|
unsigned long flag; \
|
|
__asm__("cmp %2, %0; movlo %0, #0" \
|
|
: "=&r" (flag) \
|
|
: "0" (current_thread_info()->addr_limit), "r" (addr) \
|
|
: "cc"); \
|
|
(flag == 0); })
|
|
|
|
/* We use 33-bit arithmetic here... */
|
|
#define __range_ok(addr,size) ({ \
|
|
unsigned long flag, sum; \
|
|
__chk_user_ptr(addr); \
|
|
__asm__("adds %1, %2, %3; sbcccs %1, %1, %0; movcc %0, #0" \
|
|
: "=&r" (flag), "=&r" (sum) \
|
|
: "r" (addr), "Ir" (size), "0" (current_thread_info()->addr_limit) \
|
|
: "cc"); \
|
|
flag; })
|
|
|
|
/*
|
|
* Single-value transfer routines. They automatically use the right
|
|
* size if we just have the right pointer type. Note that the functions
|
|
* which read from user space (*get_*) need to take care not to leak
|
|
* kernel data even if the calling code is buggy and fails to check
|
|
* the return value. This means zeroing out the destination variable
|
|
* or buffer on error. Normally this is done out of line by the
|
|
* fixup code, but there are a few places where it intrudes on the
|
|
* main code path. When we only write to user space, there is no
|
|
* problem.
|
|
*/
|
|
extern int __get_user_1(void *);
|
|
extern int __get_user_2(void *);
|
|
extern int __get_user_4(void *);
|
|
|
|
#define __get_user_x(__r2,__p,__e,__s,__i...) \
|
|
__asm__ __volatile__ ( \
|
|
__asmeq("%0", "r0") __asmeq("%1", "r2") \
|
|
"bl __get_user_" #__s \
|
|
: "=&r" (__e), "=r" (__r2) \
|
|
: "0" (__p) \
|
|
: __i, "cc")
|
|
|
|
#define get_user(x,p) \
|
|
({ \
|
|
const register typeof(*(p)) __user *__p asm("r0") = (p);\
|
|
register unsigned long __r2 asm("r2"); \
|
|
register int __e asm("r0"); \
|
|
switch (sizeof(*(__p))) { \
|
|
case 1: \
|
|
__get_user_x(__r2, __p, __e, 1, "lr"); \
|
|
break; \
|
|
case 2: \
|
|
__get_user_x(__r2, __p, __e, 2, "r3", "lr"); \
|
|
break; \
|
|
case 4: \
|
|
__get_user_x(__r2, __p, __e, 4, "lr"); \
|
|
break; \
|
|
default: __e = __get_user_bad(); break; \
|
|
} \
|
|
x = (typeof(*(p))) __r2; \
|
|
__e; \
|
|
})
|
|
|
|
extern int __put_user_1(void *, unsigned int);
|
|
extern int __put_user_2(void *, unsigned int);
|
|
extern int __put_user_4(void *, unsigned int);
|
|
extern int __put_user_8(void *, unsigned long long);
|
|
|
|
#define __put_user_x(__r2,__p,__e,__s) \
|
|
__asm__ __volatile__ ( \
|
|
__asmeq("%0", "r0") __asmeq("%2", "r2") \
|
|
"bl __put_user_" #__s \
|
|
: "=&r" (__e) \
|
|
: "0" (__p), "r" (__r2) \
|
|
: "ip", "lr", "cc")
|
|
|
|
#define put_user(x,p) \
|
|
({ \
|
|
const register typeof(*(p)) __r2 asm("r2") = (x); \
|
|
const register typeof(*(p)) __user *__p asm("r0") = (p);\
|
|
register int __e asm("r0"); \
|
|
switch (sizeof(*(__p))) { \
|
|
case 1: \
|
|
__put_user_x(__r2, __p, __e, 1); \
|
|
break; \
|
|
case 2: \
|
|
__put_user_x(__r2, __p, __e, 2); \
|
|
break; \
|
|
case 4: \
|
|
__put_user_x(__r2, __p, __e, 4); \
|
|
break; \
|
|
case 8: \
|
|
__put_user_x(__r2, __p, __e, 8); \
|
|
break; \
|
|
default: __e = __put_user_bad(); break; \
|
|
} \
|
|
__e; \
|
|
})
|
|
|
|
#else /* CONFIG_MMU */
|
|
|
|
/*
|
|
* uClinux has only one addr space, so has simplified address limits.
|
|
*/
|
|
#define USER_DS KERNEL_DS
|
|
|
|
#define segment_eq(a,b) (1)
|
|
#define __addr_ok(addr) (1)
|
|
#define __range_ok(addr,size) (0)
|
|
#define get_fs() (KERNEL_DS)
|
|
|
|
static inline void set_fs(mm_segment_t fs)
|
|
{
|
|
}
|
|
|
|
#define get_user(x,p) __get_user(x,p)
|
|
#define put_user(x,p) __put_user(x,p)
|
|
|
|
#endif /* CONFIG_MMU */
|
|
|
|
#define access_ok(type,addr,size) (__range_ok(addr,size) == 0)
|
|
|
|
/*
|
|
* The "__xxx" versions of the user access functions do not verify the
|
|
* address space - it must have been done previously with a separate
|
|
* "access_ok()" call.
|
|
*
|
|
* The "xxx_error" versions set the third argument to EFAULT if an
|
|
* error occurs, and leave it unchanged on success. Note that these
|
|
* versions are void (ie, don't return a value as such).
|
|
*/
|
|
#define __get_user(x,ptr) \
|
|
({ \
|
|
long __gu_err = 0; \
|
|
__get_user_err((x),(ptr),__gu_err); \
|
|
__gu_err; \
|
|
})
|
|
|
|
#define __get_user_error(x,ptr,err) \
|
|
({ \
|
|
__get_user_err((x),(ptr),err); \
|
|
(void) 0; \
|
|
})
|
|
|
|
#define __get_user_err(x,ptr,err) \
|
|
do { \
|
|
unsigned long __gu_addr = (unsigned long)(ptr); \
|
|
unsigned long __gu_val; \
|
|
__chk_user_ptr(ptr); \
|
|
switch (sizeof(*(ptr))) { \
|
|
case 1: __get_user_asm_byte(__gu_val,__gu_addr,err); break; \
|
|
case 2: __get_user_asm_half(__gu_val,__gu_addr,err); break; \
|
|
case 4: __get_user_asm_word(__gu_val,__gu_addr,err); break; \
|
|
default: (__gu_val) = __get_user_bad(); \
|
|
} \
|
|
(x) = (__typeof__(*(ptr)))__gu_val; \
|
|
} while (0)
|
|
|
|
#define __get_user_asm_byte(x,addr,err) \
|
|
__asm__ __volatile__( \
|
|
"1: ldrbt %1,[%2],#0\n" \
|
|
"2:\n" \
|
|
" .section .fixup,\"ax\"\n" \
|
|
" .align 2\n" \
|
|
"3: mov %0, %3\n" \
|
|
" mov %1, #0\n" \
|
|
" b 2b\n" \
|
|
" .previous\n" \
|
|
" .section __ex_table,\"a\"\n" \
|
|
" .align 3\n" \
|
|
" .long 1b, 3b\n" \
|
|
" .previous" \
|
|
: "+r" (err), "=&r" (x) \
|
|
: "r" (addr), "i" (-EFAULT) \
|
|
: "cc")
|
|
|
|
#ifndef __ARMEB__
|
|
#define __get_user_asm_half(x,__gu_addr,err) \
|
|
({ \
|
|
unsigned long __b1, __b2; \
|
|
__get_user_asm_byte(__b1, __gu_addr, err); \
|
|
__get_user_asm_byte(__b2, __gu_addr + 1, err); \
|
|
(x) = __b1 | (__b2 << 8); \
|
|
})
|
|
#else
|
|
#define __get_user_asm_half(x,__gu_addr,err) \
|
|
({ \
|
|
unsigned long __b1, __b2; \
|
|
__get_user_asm_byte(__b1, __gu_addr, err); \
|
|
__get_user_asm_byte(__b2, __gu_addr + 1, err); \
|
|
(x) = (__b1 << 8) | __b2; \
|
|
})
|
|
#endif
|
|
|
|
#define __get_user_asm_word(x,addr,err) \
|
|
__asm__ __volatile__( \
|
|
"1: ldrt %1,[%2],#0\n" \
|
|
"2:\n" \
|
|
" .section .fixup,\"ax\"\n" \
|
|
" .align 2\n" \
|
|
"3: mov %0, %3\n" \
|
|
" mov %1, #0\n" \
|
|
" b 2b\n" \
|
|
" .previous\n" \
|
|
" .section __ex_table,\"a\"\n" \
|
|
" .align 3\n" \
|
|
" .long 1b, 3b\n" \
|
|
" .previous" \
|
|
: "+r" (err), "=&r" (x) \
|
|
: "r" (addr), "i" (-EFAULT) \
|
|
: "cc")
|
|
|
|
#define __put_user(x,ptr) \
|
|
({ \
|
|
long __pu_err = 0; \
|
|
__put_user_err((x),(ptr),__pu_err); \
|
|
__pu_err; \
|
|
})
|
|
|
|
#define __put_user_error(x,ptr,err) \
|
|
({ \
|
|
__put_user_err((x),(ptr),err); \
|
|
(void) 0; \
|
|
})
|
|
|
|
#define __put_user_err(x,ptr,err) \
|
|
do { \
|
|
unsigned long __pu_addr = (unsigned long)(ptr); \
|
|
__typeof__(*(ptr)) __pu_val = (x); \
|
|
__chk_user_ptr(ptr); \
|
|
switch (sizeof(*(ptr))) { \
|
|
case 1: __put_user_asm_byte(__pu_val,__pu_addr,err); break; \
|
|
case 2: __put_user_asm_half(__pu_val,__pu_addr,err); break; \
|
|
case 4: __put_user_asm_word(__pu_val,__pu_addr,err); break; \
|
|
case 8: __put_user_asm_dword(__pu_val,__pu_addr,err); break; \
|
|
default: __put_user_bad(); \
|
|
} \
|
|
} while (0)
|
|
|
|
#define __put_user_asm_byte(x,__pu_addr,err) \
|
|
__asm__ __volatile__( \
|
|
"1: strbt %1,[%2],#0\n" \
|
|
"2:\n" \
|
|
" .section .fixup,\"ax\"\n" \
|
|
" .align 2\n" \
|
|
"3: mov %0, %3\n" \
|
|
" b 2b\n" \
|
|
" .previous\n" \
|
|
" .section __ex_table,\"a\"\n" \
|
|
" .align 3\n" \
|
|
" .long 1b, 3b\n" \
|
|
" .previous" \
|
|
: "+r" (err) \
|
|
: "r" (x), "r" (__pu_addr), "i" (-EFAULT) \
|
|
: "cc")
|
|
|
|
#ifndef __ARMEB__
|
|
#define __put_user_asm_half(x,__pu_addr,err) \
|
|
({ \
|
|
unsigned long __temp = (unsigned long)(x); \
|
|
__put_user_asm_byte(__temp, __pu_addr, err); \
|
|
__put_user_asm_byte(__temp >> 8, __pu_addr + 1, err); \
|
|
})
|
|
#else
|
|
#define __put_user_asm_half(x,__pu_addr,err) \
|
|
({ \
|
|
unsigned long __temp = (unsigned long)(x); \
|
|
__put_user_asm_byte(__temp >> 8, __pu_addr, err); \
|
|
__put_user_asm_byte(__temp, __pu_addr + 1, err); \
|
|
})
|
|
#endif
|
|
|
|
#define __put_user_asm_word(x,__pu_addr,err) \
|
|
__asm__ __volatile__( \
|
|
"1: strt %1,[%2],#0\n" \
|
|
"2:\n" \
|
|
" .section .fixup,\"ax\"\n" \
|
|
" .align 2\n" \
|
|
"3: mov %0, %3\n" \
|
|
" b 2b\n" \
|
|
" .previous\n" \
|
|
" .section __ex_table,\"a\"\n" \
|
|
" .align 3\n" \
|
|
" .long 1b, 3b\n" \
|
|
" .previous" \
|
|
: "+r" (err) \
|
|
: "r" (x), "r" (__pu_addr), "i" (-EFAULT) \
|
|
: "cc")
|
|
|
|
#ifndef __ARMEB__
|
|
#define __reg_oper0 "%R2"
|
|
#define __reg_oper1 "%Q2"
|
|
#else
|
|
#define __reg_oper0 "%Q2"
|
|
#define __reg_oper1 "%R2"
|
|
#endif
|
|
|
|
#define __put_user_asm_dword(x,__pu_addr,err) \
|
|
__asm__ __volatile__( \
|
|
"1: strt " __reg_oper1 ", [%1], #4\n" \
|
|
"2: strt " __reg_oper0 ", [%1], #0\n" \
|
|
"3:\n" \
|
|
" .section .fixup,\"ax\"\n" \
|
|
" .align 2\n" \
|
|
"4: mov %0, %3\n" \
|
|
" b 3b\n" \
|
|
" .previous\n" \
|
|
" .section __ex_table,\"a\"\n" \
|
|
" .align 3\n" \
|
|
" .long 1b, 4b\n" \
|
|
" .long 2b, 4b\n" \
|
|
" .previous" \
|
|
: "+r" (err), "+r" (__pu_addr) \
|
|
: "r" (x), "i" (-EFAULT) \
|
|
: "cc")
|
|
|
|
|
|
#ifdef CONFIG_MMU
|
|
extern unsigned long __copy_from_user(void *to, const void __user *from, unsigned long n);
|
|
extern unsigned long __copy_to_user(void __user *to, const void *from, unsigned long n);
|
|
extern unsigned long __clear_user(void __user *addr, unsigned long n);
|
|
#else
|
|
#define __copy_from_user(to,from,n) (memcpy(to, (void __force *)from, n), 0)
|
|
#define __copy_to_user(to,from,n) (memcpy((void __force *)to, from, n), 0)
|
|
#define __clear_user(addr,n) (memset((void __force *)addr, 0, n), 0)
|
|
#endif
|
|
|
|
extern unsigned long __strncpy_from_user(char *to, const char __user *from, unsigned long count);
|
|
extern unsigned long __strnlen_user(const char __user *s, long n);
|
|
|
|
static inline unsigned long copy_from_user(void *to, const void __user *from, unsigned long n)
|
|
{
|
|
if (access_ok(VERIFY_READ, from, n))
|
|
n = __copy_from_user(to, from, n);
|
|
else /* security hole - plug it */
|
|
memzero(to, n);
|
|
return n;
|
|
}
|
|
|
|
static inline unsigned long copy_to_user(void __user *to, const void *from, unsigned long n)
|
|
{
|
|
if (access_ok(VERIFY_WRITE, to, n))
|
|
n = __copy_to_user(to, from, n);
|
|
return n;
|
|
}
|
|
|
|
#define __copy_to_user_inatomic __copy_to_user
|
|
#define __copy_from_user_inatomic __copy_from_user
|
|
|
|
static inline unsigned long clear_user(void __user *to, unsigned long n)
|
|
{
|
|
if (access_ok(VERIFY_WRITE, to, n))
|
|
n = __clear_user(to, n);
|
|
return n;
|
|
}
|
|
|
|
static inline long strncpy_from_user(char *dst, const char __user *src, long count)
|
|
{
|
|
long res = -EFAULT;
|
|
if (access_ok(VERIFY_READ, src, 1))
|
|
res = __strncpy_from_user(dst, src, count);
|
|
return res;
|
|
}
|
|
|
|
#define strlen_user(s) strnlen_user(s, ~0UL >> 1)
|
|
|
|
static inline long strnlen_user(const char __user *s, long n)
|
|
{
|
|
unsigned long res = 0;
|
|
|
|
if (__addr_ok(s))
|
|
res = __strnlen_user(s, n);
|
|
|
|
return res;
|
|
}
|
|
|
|
#endif /* _ASMARM_UACCESS_H */
|