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
|
// SPDX-License-Identifier: MIT
// SPDX-FileCopyrightText: 2024 Michael Jeanson <mjeanson@efficios.com>
#ifndef _GNU_SOURCE
#define _GNU_SOURCE
#endif
#include <assert.h>
#include <stdint.h>
#include <syscall.h>
#include <string.h>
#include <unistd.h>
#include "rseq.h"
static int sys_rseq(void *rseq_abi, uint32_t rseq_len,
int flags, uint32_t sig)
{
return syscall(__NR_rseq, rseq_abi, rseq_len, flags, sig);
}
/*
* Check the value of errno on some expected failures of the rseq syscall.
*/
int main(void)
{
struct rseq_abi *global_rseq = rseq_get_abi();
int ret;
int errno_copy;
if (!rseq_available()) {
fprintf(stderr, "rseq syscall unavailable");
goto error;
}
/* The current thread is NOT registered. */
/* EINVAL */
errno = 0;
ret = sys_rseq(global_rseq, 32, -1, RSEQ_SIG);
errno_copy = errno;
fprintf(stderr, "Registration with invalid flag fails with errno set to EINVAL (ret = %d, errno = %s)\n", ret, strerrorname_np(errno_copy));
if (ret == 0 || errno_copy != EINVAL)
goto error;
errno = 0;
ret = sys_rseq((char *) global_rseq + 1, 32, 0, RSEQ_SIG);
errno_copy = errno;
fprintf(stderr, "Registration with unaligned rseq_abi fails with errno set to EINVAL (ret = %d, errno = %s)\n", ret, strerrorname_np(errno_copy));
if (ret == 0 || errno_copy != EINVAL)
goto error;
errno = 0;
ret = sys_rseq(global_rseq, 31, 0, RSEQ_SIG);
errno_copy = errno;
fprintf(stderr, "Registration with invalid size fails with errno set to EINVAL (ret = %d, errno = %s)\n", ret, strerrorname_np(errno_copy));
if (ret == 0 || errno_copy != EINVAL)
goto error;
#if defined(__LP64__) && (!defined(__s390__) && !defined(__s390x__))
/*
* We haven't found a reliable way to find an invalid address when
* running a 32bit userspace on a 64bit kernel, so only run this test
* on 64bit builds for the moment.
*
* Also exclude architectures that select
* CONFIG_ALTERNATE_USER_ADDRESS_SPACE where the kernel and userspace
* have their own address space and this failure can't happen.
*/
/* EFAULT */
errno = 0;
ret = sys_rseq((void *) -4096UL, 32, 0, RSEQ_SIG);
errno_copy = errno;
fprintf(stderr, "Registration with invalid address fails with errno set to EFAULT (ret = %d, errno = %s)\n", ret, strerrorname_np(errno_copy));
if (ret == 0 || errno_copy != EFAULT)
goto error;
#endif
errno = 0;
ret = sys_rseq(global_rseq, 32, 0, RSEQ_SIG);
errno_copy = errno;
fprintf(stderr, "Registration succeeds for the current thread (ret = %d, errno = %s)\n", ret, strerrorname_np(errno_copy));
if (ret != 0 && errno != 0)
goto error;
/* The current thread is registered. */
/* EBUSY */
errno = 0;
ret = sys_rseq(global_rseq, 32, 0, RSEQ_SIG);
errno_copy = errno;
fprintf(stderr, "Double registration fails with errno set to EBUSY (ret = %d, errno = %s)\n", ret, strerrorname_np(errno_copy));
if (ret == 0 || errno_copy != EBUSY)
goto error;
/* EPERM */
errno = 0;
ret = sys_rseq(global_rseq, 32, RSEQ_ABI_FLAG_UNREGISTER, RSEQ_SIG + 1);
errno_copy = errno;
fprintf(stderr, "Unregistration with wrong RSEQ_SIG fails with errno to EPERM (ret = %d, errno = %s)\n", ret, strerrorname_np(errno_copy));
if (ret == 0 || errno_copy != EPERM)
goto error;
errno = 0;
ret = sys_rseq(global_rseq, 32, RSEQ_ABI_FLAG_UNREGISTER, RSEQ_SIG);
errno_copy = errno;
fprintf(stderr, "Unregistration succeeds for the current thread (ret = %d, errno = %s)\n", ret, strerrorname_np(errno_copy));
if (ret != 0)
goto error;
errno = 0;
ret = sys_rseq(global_rseq, 32, RSEQ_ABI_FLAG_UNREGISTER, RSEQ_SIG);
errno_copy = errno;
fprintf(stderr, "Double unregistration fails with errno set to EINVAL (ret = %d, errno = %s)\n", ret, strerrorname_np(errno_copy));
if (ret == 0 || errno_copy != EINVAL)
goto error;
return 0;
error:
return -1;
}
|
