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
|
/*
* Check decoding of getgroups/getgroups32 syscalls.
*
* Copyright (c) 2016 Dmitry V. Levin <ldv@altlinux.org>
* Copyright (c) 2016-2018 The strace developers.
* All rights reserved.
*
* SPDX-License-Identifier: GPL-2.0-or-later
*/
#ifdef __NR_getgroups32
# define SYSCALL_NR __NR_getgroups32
# define SYSCALL_NAME "getgroups32"
# define GID_TYPE unsigned int
#else
# include "tests.h"
# include <asm/unistd.h>
# ifdef __NR_getgroups
# define SYSCALL_NR __NR_getgroups
# define SYSCALL_NAME "getgroups"
# if defined __NR_getgroups32 && __NR_getgroups != __NR_getgroups32
# define GID_TYPE unsigned short
# else
# define GID_TYPE unsigned int
# endif
# endif
#endif
#ifdef GID_TYPE
# include <stdio.h>
# include <unistd.h>
# define MAX_STRLEN 32
static long ngroups;
static void
get_groups(const long size, GID_TYPE *const g)
{
long i = syscall(SYSCALL_NR, size, g);
if (i != ngroups)
perror_msg_and_fail("%s(%#lx, %p)", SYSCALL_NAME, size, g);
printf("%s(%d, [", SYSCALL_NAME, (int) size);
for (i = 0; i < ngroups; ++i) {
if (i)
printf(", ");
if (i >= MAX_STRLEN) {
printf("...");
break;
}
printf("%u", (unsigned int) g[i]);
}
printf("]) = %ld\n", ngroups);
}
int
main(void)
{
long rc;
/* check how the first argument is decoded */
ngroups = syscall(SYSCALL_NR, 0, 0);
printf("%s(0, NULL) = %ld\n", SYSCALL_NAME, ngroups);
if (ngroups < 0)
perror_msg_and_fail(SYSCALL_NAME);
rc = syscall(SYSCALL_NR, F8ILL_KULONG_MASK, 0);
printf("%s(0, NULL) = %ld\n", SYSCALL_NAME, rc);
rc = syscall(SYSCALL_NR, -1U, 0);
printf("%s(%d, NULL) = %s\n", SYSCALL_NAME, -1, sprintrc(rc));
rc = syscall(SYSCALL_NR, -1L, 0);
printf("%s(%d, NULL) = %s\n", SYSCALL_NAME, -1, sprintrc(rc));
const unsigned int ngroups_max = sysconf(_SC_NGROUPS_MAX);
rc = syscall(SYSCALL_NR, ngroups_max, 0);
printf("%s(%d, NULL) = %s\n", SYSCALL_NAME, ngroups_max, sprintrc(rc));
rc = syscall(SYSCALL_NR, F8ILL_KULONG_MASK | ngroups_max, 0);
printf("%s(%d, NULL) = %s\n", SYSCALL_NAME, ngroups_max, sprintrc(rc));
/* check how the second argument is decoded */
GID_TYPE *const g1 =
tail_alloc(ngroups ? sizeof(*g1) * ngroups : 1);
GID_TYPE *const g2 = tail_alloc(sizeof(*g2) * (ngroups + 1));
void *efault = g2 + ngroups + 1;
get_groups(ngroups, g1);
get_groups(ngroups + 1, g1);
get_groups(ngroups + 1, g2);
if (ngroups) {
rc = syscall(SYSCALL_NR, ngroups, efault);
printf("%s(%d, %p) = %s\n",
SYSCALL_NAME, (unsigned) ngroups, efault, sprintrc(rc));
}
puts("+++ exited with 0 +++");
return 0;
}
#else
SKIP_MAIN_UNDEFINED("__NR_getgroups")
#endif
|