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
166
167
168
169
170
171
172
173
174
175
176
177
178
|
/* Testing s390x PTRACE_SINGLEBLOCK ptrace request.
Copyright (C) 2017-2021 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, see
<https://www.gnu.org/licenses/>. */
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <sys/wait.h>
#include <sys/types.h>
#include <sys/uio.h>
#include <elf.h>
#include <support/xunistd.h>
#include <support/check.h>
#include <string.h>
#include <errno.h>
/* Ensure that we use the PTRACE_SINGLEBLOCK definition from glibc ptrace.h
in tracer_func. We need the kernel ptrace.h for structs ptrace_area
and gregset_t. */
#include <sys/ptrace.h>
static const enum __ptrace_request req_singleblock = PTRACE_SINGLEBLOCK;
#include <asm/ptrace.h>
static void
tracee_func (int pid)
{
/* Dump the mapping information for manual inspection of the printed
tracee addresses. */
char str[80];
sprintf (str, "cat /proc/%d/maps", pid);
puts (str);
system (str);
fflush (stdout);
TEST_VERIFY_EXIT (ptrace (PTRACE_TRACEME) == 0);
/* Stop tracee. Afterwards the tracer_func can operate. */
kill (pid, SIGSTOP);
puts ("The PTRACE_SINGLEBLOCK of the tracer will stop after: "
"brasl %r14,<puts@plt>!");
}
static void
tracer_func (int pid)
{
unsigned long last_break;
ptrace_area parea;
gregset_t regs;
struct iovec parea2;
gregset_t regs2;
int status;
int ret;
#define MAX_CHARS_IN_BUF 4096
char buf[MAX_CHARS_IN_BUF + 1];
size_t buf_count;
while (1)
{
/* Wait for the tracee to be stopped or exited. */
wait (&status);
if (WIFEXITED (status))
break;
/* Get information about tracee: gprs, last breaking address. */
parea.len = sizeof (regs);
parea.process_addr = (unsigned long) ®s;
parea.kernel_addr = 0;
TEST_VERIFY_EXIT (ptrace (PTRACE_PEEKUSR_AREA, pid, &parea) == 0);
TEST_VERIFY_EXIT (ptrace (PTRACE_GET_LAST_BREAK, pid, NULL, &last_break)
== 0);
parea2.iov_len = sizeof (regs2);
parea2.iov_base = ®s2;
TEST_VERIFY_EXIT (ptrace (PTRACE_GETREGSET, pid, NT_PRSTATUS, &parea2)
== 0);
TEST_VERIFY_EXIT (parea2.iov_len == sizeof (regs2));
/* Test if gprs obtained by PTRACE_PEEKUSR_AREA and PTRACE_GETREGESET
have the same values. */
TEST_VERIFY_EXIT (memcmp (®s, ®s2, sizeof (regs)) == 0);
printf ("child IA: %p last_break: %p\n",
(void *) regs[1], (void *) last_break);
/* Execute tracee until next taken branch.
Note:
Before the commit which introduced this testcase,
<glibc>/sysdeps/unix/sysv/linux/s390/sys/ptrace.h
uses ptrace-request 12 for PTRACE_GETREGS,
but <kernel>/include/uapi/linux/ptrace.h
uses 12 for PTRACE_SINGLEBLOCK.
The s390 kernel has no support for PTRACE_GETREGS!
Thus glibc ptrace.h is adjusted to match kernel ptrace.h.
The glibc sys/ptrace.h header contains the identifier
PTRACE_SINGLEBLOCK in enum __ptrace_request. In contrast, the kernel
asm/ptrace.h header defines PTRACE_SINGLEBLOCK.
This test ensures, that PTRACE_SINGLEBLOCK defined in glibc
works as expected. If the kernel would interpret it as
PTRACE_GETREGS, then the tracee will not make any progress
and this testcase will time out or the ptrace call will fail with
different errors. */
/* Ptrace request 12 is first done with data argument pointing to
a buffer:
-If request 12 is interpreted as PTRACE_GETREGS, it will store the regs
to buffer without an error.
-If request 12 is interpreted as PTRACE_SINGLEBLOCK, it will fail
as data argument is used as signal-number and the address of
buf is no valid signal.
-If request 12 is not implemented, it will also fail.
Here the test expects that the buffer is untouched and an error is
returned. */
memset (buf, 'a', MAX_CHARS_IN_BUF);
ret = ptrace (req_singleblock, pid, NULL, buf);
buf [MAX_CHARS_IN_BUF] = '\0';
buf_count = strspn (buf, "a");
TEST_VERIFY_EXIT (buf_count == MAX_CHARS_IN_BUF);
TEST_VERIFY_EXIT (ret == -1);
/* If request 12 is interpreted as PTRACE_GETREGS, the first ptrace
call will touch the buffer which is detected by this test. */
errno = 0;
ret = ptrace (req_singleblock, pid, NULL, NULL);
if (ret == 0)
{
/* The kernel has support for PTRACE_SINGLEBLOCK ptrace request. */
TEST_VERIFY_EXIT (errno == 0);
}
else
{
/* The kernel (< 3.15) has no support for PTRACE_SINGLEBLOCK ptrace
request. */
TEST_VERIFY_EXIT (errno == EIO);
TEST_VERIFY_EXIT (ret == -1);
/* Just continue tracee until it exits normally. */
TEST_VERIFY_EXIT (ptrace (PTRACE_CONT, pid, NULL, NULL) == 0);
}
}
}
static int
do_test (void)
{
int pid;
pid = xfork ();
if (pid)
tracer_func (pid);
else
tracee_func (getpid ());
return EXIT_SUCCESS;
}
#include <support/test-driver.c>
|
