72 lines
1.2 KiB
C
72 lines
1.2 KiB
C
/* user_fixup.c: Fix up user copy faults.
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*
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* Copyright (C) 2004 David S. Miller <davem@redhat.com>
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*/
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#include <linux/compiler.h>
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#include <linux/kernel.h>
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#include <linux/string.h>
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#include <linux/errno.h>
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#include <asm/uaccess.h>
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/* Calculating the exact fault address when using
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* block loads and stores can be very complicated.
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* Instead of trying to be clever and handling all
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* of the cases, just fix things up simply here.
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*/
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unsigned long copy_from_user_fixup(void *to, const void __user *from, unsigned long size)
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{
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char *dst = to;
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const char __user *src = from;
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while (size) {
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if (__get_user(*dst, src))
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break;
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dst++;
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src++;
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size--;
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}
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if (size)
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memset(dst, 0, size);
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return size;
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}
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unsigned long copy_to_user_fixup(void __user *to, const void *from, unsigned long size)
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{
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char __user *dst = to;
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const char *src = from;
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while (size) {
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if (__put_user(*src, dst))
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break;
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dst++;
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src++;
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size--;
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}
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return size;
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}
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unsigned long copy_in_user_fixup(void __user *to, void __user *from, unsigned long size)
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{
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char __user *dst = to;
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char __user *src = from;
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while (size) {
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char tmp;
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if (__get_user(tmp, src))
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break;
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if (__put_user(tmp, dst))
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break;
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dst++;
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src++;
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size--;
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}
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return size;
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}
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