1 /* SPDX-License-Identifier: GPL-2.0 */ 2 /* 3 * Copyright (C) 2002 Jeff Dike (jdike@karaya.com) 4 * Copyright (C) 2015 Richard Weinberger (richard@nod.at) 5 */ 6 7 #ifndef __UM_UACCESS_H 8 #define __UM_UACCESS_H 9 10 #include <asm/elf.h> 11 #include <linux/unaligned.h> 12 #include <sysdep/faultinfo.h> 13 14 #define __under_task_size(addr, size) \ 15 (((unsigned long) (addr) < TASK_SIZE) && \ 16 (((unsigned long) (addr) + (size)) < TASK_SIZE)) 17 18 #define __access_ok_vsyscall(addr, size) \ 19 (((unsigned long) (addr) >= FIXADDR_USER_START) && \ 20 ((unsigned long) (addr) + (size) <= FIXADDR_USER_END) && \ 21 ((unsigned long) (addr) + (size) >= (unsigned long)(addr))) 22 23 #define __addr_range_nowrap(addr, size) \ 24 ((unsigned long) (addr) <= ((unsigned long) (addr) + (size))) 25 26 extern unsigned long raw_copy_from_user(void *to, const void __user *from, unsigned long n); 27 extern unsigned long raw_copy_to_user(void __user *to, const void *from, unsigned long n); 28 extern unsigned long __clear_user(void __user *mem, unsigned long len); 29 static inline int __access_ok(const void __user *ptr, unsigned long size); 30 31 /* Teach asm-generic/uaccess.h that we have C functions for these. */ 32 #define __access_ok __access_ok 33 #define __clear_user __clear_user 34 35 #define INLINE_COPY_FROM_USER 36 #define INLINE_COPY_TO_USER 37 38 #include <asm-generic/uaccess.h> 39 40 static inline int __access_ok(const void __user *ptr, unsigned long size) 41 { 42 unsigned long addr = (unsigned long)ptr; 43 return __addr_range_nowrap(addr, size) && 44 (__under_task_size(addr, size) || 45 __access_ok_vsyscall(addr, size)); 46 } 47 48 #define __get_kernel_nofault(dst, src, type, err_label) \ 49 do { \ 50 int __faulted; \ 51 \ 52 ___backtrack_faulted(__faulted); \ 53 if (__faulted) { \ 54 *((type *)dst) = (type) 0; \ 55 goto err_label; \ 56 } \ 57 *((type *)dst) = get_unaligned((type *)(src)); \ 58 barrier(); \ 59 current->thread.segv_continue = NULL; \ 60 } while (0) 61 62 #define __put_kernel_nofault(dst, src, type, err_label) \ 63 do { \ 64 int __faulted; \ 65 \ 66 ___backtrack_faulted(__faulted); \ 67 if (__faulted) \ 68 goto err_label; \ 69 put_unaligned(*((type *)src), (type *)(dst)); \ 70 barrier(); \ 71 current->thread.segv_continue = NULL; \ 72 } while (0) 73 74 #endif 75