1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
|
/* Copyright (C) 1998, 1999, 2000 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, write to the Free
Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
02111-1307 USA. */
#include <errno.h>
#include <unistd.h>
#include <sysdep.h>
#include <sys/syscall.h>
#include <shlib-compat.h>
#include <bp-checks.h>
#include <linux/posix_types.h>
#include "kernel-features.h"
/*
In Linux 2.1.x the chown functions have been changed. A new function lchown
was introduced. The new chown now follows symlinks - the old chown and the
new lchown do not follow symlinks.
The new lchown function has the same number as the old chown had and the
new chown has a new number. When compiling with headers from Linux > 2.1.8x
it's impossible to run this libc with older kernels. In these cases libc
has therefore to route calls to chown to the old chown function.
*/
extern int __syscall_chown (const char *__file,
__kernel_uid_t __owner, __kernel_gid_t __group);
extern int __chown_is_lchown (const char *__file, uid_t __owner,
gid_t __group);
extern int __real_chown (const char *__file, uid_t __owner, gid_t __group);
#if defined __NR_lchown || __ASSUME_LCHOWN_SYSCALL > 0
/* Running under Linux > 2.1.80. */
# ifdef __NR_chown32
extern int __syscall_chown32 (const char *__file,
__kernel_uid32_t owner, __kernel_gid32_t group);
# if __ASSUME_32BITUIDS == 0
/* This variable is shared with all files that need to check for 32bit
uids. */
extern int __libc_missing_32bit_uids;
# endif
# endif /* __NR_chown32 */
int
__real_chown (const char *file, uid_t owner, gid_t group)
{
# if __ASSUME_LCHOWN_SYSCALL == 0
static int __libc_old_chown;
int result;
if (!__libc_old_chown)
{
int saved_errno = errno;
# ifdef __NR_chown32
if (__libc_missing_32bit_uids <= 0)
{
int result;
int saved_errno = errno;
result = INLINE_SYSCALL (chown32, 3, CHECK_STRING (file), owner, group);
if (result == 0 || errno != ENOSYS)
return result;
__set_errno (saved_errno);
__libc_missing_32bit_uids = 1;
}
# endif /* __NR_chown32 */
if (((owner + 1) > (uid_t) ((__kernel_uid_t) -1U))
|| ((group + 1) > (gid_t) ((__kernel_gid_t) -1U)))
{
__set_errno (EINVAL);
return -1;
}
result = INLINE_SYSCALL (chown, 3, CHECK_STRING (file), owner, group);
if (result >= 0 || errno != ENOSYS)
return result;
__set_errno (saved_errno);
__libc_old_chown = 1;
}
return __lchown (file, owner, group);
# elif __ASSUME_32BITUIDS
/* This implies __ASSUME_LCHOWN_SYSCALL. */
return INLINE_SYSCALL (chown32, 3, CHECK_STRING (file), owner, group);
# else
/* !__ASSUME_32BITUIDS && ASSUME_LCHOWN_SYSCALL */
# ifdef __NR_chown32
if (__libc_missing_32bit_uids <= 0)
{
int result;
int saved_errno = errno;
result = INLINE_SYSCALL (chown32, 3, CHECK_STRING (file), owner, group);
if (result == 0 || errno != ENOSYS)
return result;
__set_errno (saved_errno);
__libc_missing_32bit_uids = 1;
}
# endif /* __NR_chown32 */
if (((owner + 1) > (uid_t) ((__kernel_uid_t) -1U))
|| ((group + 1) > (gid_t) ((__kernel_gid_t) -1U)))
{
__set_errno (EINVAL);
return -1;
}
return INLINE_SYSCALL (chown, 3, CHECK_STRING (file), owner, group);
# endif
}
#endif
#if !defined __NR_lchown && __ASSUME_LCHOWN_SYSCALL == 0
/* Compiling under older kernels. */
int
__chown_is_lchown (const char *file, uid_t owner, gid_t group)
{
return INLINE_SYSCALL (chown, 3, CHECK_STRING (file), owner, group);
}
#elif SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_1)
/* Compiling for compatibiity. */
int
__chown_is_lchown (const char *file, uid_t owner, gid_t group)
{
return __lchown (file, owner, group);
}
#endif
#if SHLIB_COMPAT (libc, GLIBC_2_0, GLIBC_2_1)
strong_alias (__chown_is_lchown, _chown_is_lchown)
compat_symbol (libc, __chown_is_lchown, __chown, GLIBC_2_0);
compat_symbol (libc, _chown_is_lchown, chown, GLIBC_2_0);
#endif
#ifdef __NR_lchown
strong_alias (__real_chown, _real_chown)
versioned_symbol (libc, __real_chown, __chown, GLIBC_2_1);
versioned_symbol (libc, _real_chown, chown, GLIBC_2_1);
#else
strong_alias (__chown_is_lchown, __chown_is_lchown21)
strong_alias (__chown_is_lchown, _chown_is_lchown21)
versioned_symbol (libc, __chown_is_lchown21, __chown, GLIBC_2_1);
versioned_symbol (libc, _chown_is_lchown21, chown, GLIBC_2_1);
#endif
|
