1#include <linux/export.h>
2#include <linux/bug.h>
 
 
 
 
3#include <linux/uaccess.h>
 
4
5void copy_from_user_overflow(void)
 
 
 
 
 
 
 
 
 
 
 
6{
7	WARN(1, "Buffer overflow detected!\n");
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
8}
9EXPORT_SYMBOL(copy_from_user_overflow);

 1// SPDX-License-Identifier: GPL-2.0
 2#include <linux/compiler.h>
 3#include <linux/errno.h>
 4#include <linux/export.h>
 5#include <linux/fault-inject-usercopy.h>
 6#include <linux/instrumented.h>
 7#include <linux/kernel.h>
 8#include <linux/nospec.h>
 9#include <linux/string.h>
10#include <linux/uaccess.h>
11#include <linux/wordpart.h>
12
13/* out-of-line parts */
14
15#if !defined(INLINE_COPY_FROM_USER) || defined(CONFIG_RUST)
16unsigned long _copy_from_user(void *to, const void __user *from, unsigned long n)
17{
18	return _inline_copy_from_user(to, from, n);
19}
20EXPORT_SYMBOL(_copy_from_user);
21#endif
22
23#if !defined(INLINE_COPY_TO_USER) || defined(CONFIG_RUST)
24unsigned long _copy_to_user(void __user *to, const void *from, unsigned long n)
25{
26	return _inline_copy_to_user(to, from, n);
27}
28EXPORT_SYMBOL(_copy_to_user);
29#endif
30
31/**
32 * check_zeroed_user: check if a userspace buffer only contains zero bytes
33 * @from: Source address, in userspace.
34 * @size: Size of buffer.
35 *
36 * This is effectively shorthand for "memchr_inv(from, 0, size) == NULL" for
37 * userspace addresses (and is more efficient because we don't care where the
38 * first non-zero byte is).
39 *
40 * Returns:
41 *  * 0: There were non-zero bytes present in the buffer.
42 *  * 1: The buffer was full of zero bytes.
43 *  * -EFAULT: access to userspace failed.
44 */
45int check_zeroed_user(const void __user *from, size_t size)
46{
47	unsigned long val;
48	uintptr_t align = (uintptr_t) from % sizeof(unsigned long);
49
50	if (unlikely(size == 0))
51		return 1;
52
53	from -= align;
54	size += align;
55
56	if (!user_read_access_begin(from, size))
57		return -EFAULT;
58
59	unsafe_get_user(val, (unsigned long __user *) from, err_fault);
60	if (align)
61		val &= ~aligned_byte_mask(align);
62
63	while (size > sizeof(unsigned long)) {
64		if (unlikely(val))
65			goto done;
66
67		from += sizeof(unsigned long);
68		size -= sizeof(unsigned long);
69
70		unsafe_get_user(val, (unsigned long __user *) from, err_fault);
71	}
72
73	if (size < sizeof(unsigned long))
74		val &= aligned_byte_mask(size);
75
76done:
77	user_read_access_end();
78	return (val == 0);
79err_fault:
80	user_read_access_end();
81	return -EFAULT;
82}
83EXPORT_SYMBOL(check_zeroed_user);