1 /* 2 * Copyright (C) 2002 Jeff Dike (jdike@karaya.com) 3 * Copyright (C) 2015 Richard Weinberger (richard@nod.at) 4 * Licensed under the GPL 5 */ 6 7 #ifndef __UM_UACCESS_H 8 #define __UM_UACCESS_H 9 10 #include <asm/thread_info.h> 11 #include <asm/elf.h> 12 13 #define __under_task_size(addr, size) \ 14 (((unsigned long) (addr) < TASK_SIZE) && \ 15 (((unsigned long) (addr) + (size)) < TASK_SIZE)) 16 17 #define __access_ok_vsyscall(addr, size) \ 18 (((unsigned long) (addr) >= FIXADDR_USER_START) && \ 19 ((unsigned long) (addr) + (size) <= FIXADDR_USER_END) && \ 20 ((unsigned long) (addr) + (size) >= (unsigned long)(addr))) 21 22 #define __addr_range_nowrap(addr, size) \ 23 ((unsigned long) (addr) <= ((unsigned long) (addr) + (size))) 24 25 extern long __copy_from_user(void *to, const void __user *from, unsigned long n); 26 extern long __copy_to_user(void __user *to, const void *from, unsigned long n); 27 extern long __strncpy_from_user(char *dst, const char __user *src, long count); 28 extern long __strnlen_user(const void __user *str, long len); 29 extern unsigned long __clear_user(void __user *mem, unsigned long len); 30 static inline int __access_ok(unsigned long addr, unsigned long size); 31 32 /* Teach asm-generic/uaccess.h that we have C functions for these. */ 33 #define __access_ok __access_ok 34 #define __clear_user __clear_user 35 #define __copy_to_user __copy_to_user 36 #define __copy_from_user __copy_from_user 37 #define __strnlen_user __strnlen_user 38 #define __strncpy_from_user __strncpy_from_user 39 #define __copy_to_user_inatomic __copy_to_user 40 #define __copy_from_user_inatomic __copy_from_user 41 42 #include <asm-generic/uaccess.h> 43 44 static inline int __access_ok(unsigned long addr, unsigned long size) 45 { 46 return __addr_range_nowrap(addr, size) && 47 (__under_task_size(addr, size) || 48 __access_ok_vsyscall(addr, size) || 49 segment_eq(get_fs(), KERNEL_DS)); 50 } 51 52 #endif 53