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-rw-r--r--arch/frv/kernel/uaccess.c95
1 files changed, 95 insertions, 0 deletions
diff --git a/arch/frv/kernel/uaccess.c b/arch/frv/kernel/uaccess.c
new file mode 100644
index 000000000000..f3fd58a5bc4a
--- /dev/null
+++ b/arch/frv/kernel/uaccess.c
@@ -0,0 +1,95 @@
1/* uaccess.c: userspace access functions
2 *
3 * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved.
4 * Written by David Howells (dhowells@redhat.com)
5 *
6 * This program is free software; you can redistribute it and/or
7 * modify it under the terms of the GNU General Public License
8 * as published by the Free Software Foundation; either version
9 * 2 of the License, or (at your option) any later version.
10 */
11
12#include <linux/mm.h>
13#include <asm/uaccess.h>
14
15/*****************************************************************************/
16/*
17 * copy a null terminated string from userspace
18 */
19long strncpy_from_user(char *dst, const char *src, long count)
20{
21 unsigned long max;
22 char *p, ch;
23 long err = -EFAULT;
24
25 if (count < 0)
26 BUG();
27
28 p = dst;
29
30#ifndef CONFIG_MMU
31 if ((unsigned long) src < memory_start)
32 goto error;
33#endif
34
35 if ((unsigned long) src >= get_addr_limit())
36 goto error;
37
38 max = get_addr_limit() - (unsigned long) src;
39 if ((unsigned long) count > max) {
40 memset(dst + max, 0, count - max);
41 count = max;
42 }
43
44 err = 0;
45 for (; count > 0; count--, p++, src++) {
46 __get_user_asm(err, ch, src, "ub", "=r");
47 if (err < 0)
48 goto error;
49 if (!ch)
50 break;
51 *p = ch;
52 }
53
54 err = p - dst; /* return length excluding NUL */
55
56 error:
57 if (count > 0)
58 memset(p, 0, count); /* clear remainder of buffer [security] */
59
60 return err;
61} /* end strncpy_from_user() */
62
63/*****************************************************************************/
64/*
65 * Return the size of a string (including the ending 0)
66 *
67 * Return 0 on exception, a value greater than N if too long
68 */
69long strnlen_user(const char *src, long count)
70{
71 const char *p;
72 long err = 0;
73 char ch;
74
75 if (count < 0)
76 BUG();
77
78#ifndef CONFIG_MMU
79 if ((unsigned long) src < memory_start)
80 return 0;
81#endif
82
83 if ((unsigned long) src >= get_addr_limit())
84 return 0;
85
86 for (p = src; count > 0; count--, p++) {
87 __get_user_asm(err, ch, p, "ub", "=r");
88 if (err < 0)
89 return 0;
90 if (!ch)
91 break;
92 }
93
94 return p - src + 1; /* return length including NUL */
95} /* end strnlen_user() */