xref: /linux/lib/usercopy.c (revision 905e46acd3272d04566fec49afbd7ad9e2ed9ae3)
1 #include <linux/uaccess.h>
2 
3 /* out-of-line parts */
4 
5 #ifndef INLINE_COPY_FROM_USER
6 unsigned long _copy_from_user(void *to, const void __user *from, unsigned long n)
7 {
8 	unsigned long res = n;
9 	if (likely(access_ok(VERIFY_READ, from, n)))
10 		res = raw_copy_from_user(to, from, n);
11 	if (unlikely(res))
12 		memset(to + (n - res), 0, res);
13 	return res;
14 }
15 EXPORT_SYMBOL(_copy_from_user);
16 #endif
17 
18 #ifndef INLINE_COPY_TO_USER
19 unsigned long _copy_to_user(void *to, const void __user *from, unsigned long n)
20 {
21 	if (likely(access_ok(VERIFY_WRITE, to, n)))
22 		n = raw_copy_to_user(to, from, n);
23 	return n;
24 }
25 EXPORT_SYMBOL(_copy_to_user);
26 #endif
27