From f8d65d27e677da0ce33de570e3068308a77ed2b1 Mon Sep 17 00:00:00 2001 From: Richard Weinberger Date: Tue, 12 May 2015 00:17:28 +0200 Subject: um: Rework uaccess code Rework UML's uaccess code to reuse as much as possible from asm-generic/uaccess.c. Signed-off-by: Richard Weinberger --- arch/um/include/asm/uaccess.h | 176 ++++++------------------------------------ 1 file changed, 25 insertions(+), 151 deletions(-) (limited to 'arch/um/include/asm/uaccess.h') diff --git a/arch/um/include/asm/uaccess.h b/arch/um/include/asm/uaccess.h index 3f22fbf7ca1d..3705620ca298 100644 --- a/arch/um/include/asm/uaccess.h +++ b/arch/um/include/asm/uaccess.h @@ -1,178 +1,52 @@ /* * Copyright (C) 2002 Jeff Dike (jdike@karaya.com) + * Copyright (C) 2015 Richard Weinberger (richard@nod.at) * Licensed under the GPL */ #ifndef __UM_UACCESS_H #define __UM_UACCESS_H -/* thread_info has a mm_segment_t in it, so put the definition up here */ -typedef struct { - unsigned long seg; -} mm_segment_t; - -#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(0xFFFFFFFF) -#define USER_DS MAKE_MM_SEG(TASK_SIZE) - -#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 __under_task_size(addr, size) \ (((unsigned long) (addr) < TASK_SIZE) && \ (((unsigned long) (addr) + (size)) < TASK_SIZE)) -#define __access_ok_vsyscall(type, addr, size) \ - ((type == VERIFY_READ) && \ - ((unsigned long) (addr) >= FIXADDR_USER_START) && \ +#define __access_ok_vsyscall(addr, size) \ + (((unsigned long) (addr) >= FIXADDR_USER_START) && \ ((unsigned long) (addr) + (size) <= FIXADDR_USER_END) && \ ((unsigned long) (addr) + (size) >= (unsigned long)(addr))) #define __addr_range_nowrap(addr, size) \ ((unsigned long) (addr) <= ((unsigned long) (addr) + (size))) -#define access_ok(type, addr, size) \ - (__addr_range_nowrap(addr, size) && \ - (__under_task_size(addr, size) || \ - __access_ok_vsyscall(type, addr, size) || \ - segment_eq(get_fs(), KERNEL_DS))) - -extern int copy_from_user(void *to, const void __user *from, int n); -extern int copy_to_user(void __user *to, const void *from, int n); - -/* - * strncpy_from_user: - Copy a NUL terminated string from userspace. - * @dst: Destination address, in kernel space. This buffer must be at - * least @count bytes long. - * @src: Source address, in user space. - * @count: Maximum number of bytes to copy, including the trailing NUL. - * - * Copies a NUL-terminated string from userspace to kernel space. - * - * On success, returns the length of the string (not including the trailing - * NUL). - * - * If access to userspace fails, returns -EFAULT (some data may have been - * copied). - * - * If @count is smaller than the length of the string, copies @count bytes - * and returns @count. - */ - -extern int strncpy_from_user(char *dst, const char __user *src, int count); - -/* - * __clear_user: - Zero a block of memory in user space, with less checking. - * @to: Destination address, in user space. - * @n: Number of bytes to zero. - * - * Zero a block of memory in user space. Caller must check - * the specified block with access_ok() before calling this function. - * - * Returns number of bytes that could not be cleared. - * On success, this will be zero. - */ -extern int __clear_user(void __user *mem, int len); - -/* - * clear_user: - Zero a block of memory in user space. - * @to: Destination address, in user space. - * @n: Number of bytes to zero. - * - * Zero a block of memory in user space. - * - * Returns number of bytes that could not be cleared. - * On success, this will be zero. - */ -extern int clear_user(void __user *mem, int len); - -/* - * strlen_user: - Get the size of a string in user space. - * @str: The string to measure. - * @n: The maximum valid length - * - * Get the size of a NUL-terminated string in user space. - * - * Returns the size of the string INCLUDING the terminating NUL. - * On exception, returns 0. - * If the string is too long, returns a value greater than @n. - */ -extern int strnlen_user(const void __user *str, int len); - -#define __copy_from_user(to, from, n) copy_from_user(to, from, n) - -#define __copy_to_user(to, from, n) copy_to_user(to, from, n) - +extern long __copy_from_user(void *to, const void __user *from, unsigned long n); +extern long __copy_to_user(void __user *to, const void *from, unsigned long n); +extern long __strncpy_from_user(char *dst, const char __user *src, long count); +extern long __strnlen_user(const void __user *str, long len); +extern unsigned long __clear_user(void __user *mem, unsigned long len); +static inline int __access_ok(unsigned long addr, unsigned long size); + +/* Teach asm-generic/uaccess.h that we have C functions for these. */ +#define __access_ok __access_ok +#define __clear_user __clear_user +#define __copy_to_user __copy_to_user +#define __copy_from_user __copy_from_user +#define __strnlen_user __strnlen_user +#define __strncpy_from_user __strncpy_from_user #define __copy_to_user_inatomic __copy_to_user #define __copy_from_user_inatomic __copy_from_user -#define __get_user(x, ptr) \ -({ \ - const __typeof__(*(ptr)) __user *__private_ptr = (ptr); \ - __typeof__(x) __private_val; \ - int __private_ret = -EFAULT; \ - (x) = (__typeof__(*(__private_ptr)))0; \ - if (__copy_from_user((__force void *)&__private_val, (__private_ptr),\ - sizeof(*(__private_ptr))) == 0) { \ - (x) = (__typeof__(*(__private_ptr))) __private_val; \ - __private_ret = 0; \ - } \ - __private_ret; \ -}) - -#define get_user(x, ptr) \ -({ \ - const __typeof__((*(ptr))) __user *private_ptr = (ptr); \ - (access_ok(VERIFY_READ, private_ptr, sizeof(*private_ptr)) ? \ - __get_user(x, private_ptr) : ((x) = (__typeof__(*ptr))0, -EFAULT)); \ -}) - -#define __put_user(x, ptr) \ -({ \ - __typeof__(*(ptr)) __user *__private_ptr = ptr; \ - __typeof__(*(__private_ptr)) __private_val; \ - int __private_ret = -EFAULT; \ - __private_val = (__typeof__(*(__private_ptr))) (x); \ - if (__copy_to_user((__private_ptr), &__private_val, \ - sizeof(*(__private_ptr))) == 0) { \ - __private_ret = 0; \ - } \ - __private_ret; \ -}) - -#define put_user(x, ptr) \ -({ \ - __typeof__(*(ptr)) __user *private_ptr = (ptr); \ - (access_ok(VERIFY_WRITE, private_ptr, sizeof(*private_ptr)) ? \ - __put_user(x, private_ptr) : -EFAULT); \ -}) - -#define strlen_user(str) strnlen_user(str, ~0U >> 1) +#include -struct exception_table_entry +static inline int __access_ok(unsigned long addr, unsigned long size) { - unsigned long insn; - unsigned long fixup; -}; + return __addr_range_nowrap(addr, size) && + (__under_task_size(addr, size) || + __access_ok_vsyscall(addr, size) || + segment_eq(get_fs(), KERNEL_DS)); +} #endif -- cgit v1.2.3