1 | /* Test the stack guard. |
2 | Copyright (C) 2000-2024 Free Software Foundation, Inc. |
3 | This file is part of the GNU C Library. |
4 | |
5 | The GNU C Library is free software; you can redistribute it and/or |
6 | modify it under the terms of the GNU Lesser General Public |
7 | License as published by the Free Software Foundation; either |
8 | version 2.1 of the License, or (at your option) any later version. |
9 | |
10 | The GNU C Library is distributed in the hope that it will be useful, |
11 | but WITHOUT ANY WARRANTY; without even the implied warranty of |
12 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
13 | Lesser General Public License for more details. |
14 | |
15 | You should have received a copy of the GNU Lesser General Public |
16 | License along with the GNU C Library; if not, see |
17 | <https://www.gnu.org/licenses/>. */ |
18 | |
19 | #define _GNU_SOURCE |
20 | |
21 | #include <pthread.h> |
22 | #include <assert.h> |
23 | #include <unistd.h> |
24 | #include <errno.h> |
25 | #include <string.h> |
26 | #include <stdio.h> |
27 | |
28 | size_t stacksize; |
29 | |
30 | void * |
31 | thr (void *arg) |
32 | { |
33 | int i; |
34 | char *foo; |
35 | |
36 | foo = alloca (3 * stacksize / 4); |
37 | for (i = 0; i < sizeof foo; i++) |
38 | foo[i] = -1; |
39 | |
40 | return (void *) 1; |
41 | } |
42 | |
43 | int |
44 | main (int argc, char *argv[]) |
45 | { |
46 | error_t err; |
47 | pid_t child; |
48 | |
49 | child = fork (); |
50 | switch (child) |
51 | { |
52 | case -1: |
53 | error (1, errno, "fork" ); |
54 | break; |
55 | |
56 | case 0: |
57 | { |
58 | pthread_attr_t attr; |
59 | pthread_t tid; |
60 | void *ret; |
61 | |
62 | err = pthread_attr_init (attr: &attr); |
63 | assert_perror (err); |
64 | |
65 | err = pthread_attr_getstacksize (attr: &attr, stacksize: &stacksize); |
66 | assert_perror (err); |
67 | |
68 | err = pthread_attr_setguardsize (attr: &attr, guardsize: stacksize / 2); |
69 | if (err == ENOTSUP) |
70 | { |
71 | printf (format: "Stack guard attribute not supported.\n" ); |
72 | return 1; |
73 | } |
74 | assert_perror (err); |
75 | |
76 | err = pthread_create (newthread: &tid, attr: &attr, start_routine: thr, arg: 0); |
77 | assert_perror (err); |
78 | |
79 | err = pthread_attr_destroy (attr: &attr); |
80 | assert_perror (err); |
81 | |
82 | err = pthread_join (th: tid, thread_return: &ret); |
83 | /* Should never be successful. */ |
84 | printf (format: "Thread did not segfault!?!\n" ); |
85 | assert_perror (err); |
86 | return 0; |
87 | } |
88 | |
89 | default: |
90 | { |
91 | pid_t pid; |
92 | int status; |
93 | |
94 | pid = waitpid (child, &status, 0); |
95 | printf (format: "pid = %d; child = %d; status = %d\n" , pid, child, status); |
96 | assert (pid == child); |
97 | assert (status != 0); |
98 | } |
99 | } |
100 | |
101 | return 0; |
102 | } |
103 | |